** Destinations for output text.
*/
#define CGI_HEADER   0
#define CGI_BODY     1

#endif /* INTERFACE */








/*
** The HTTP reply is generated in two pieces: the header and the body.
** These pieces are generated separately because they are not necessary
** produced in order.  Parts of the header might be built after all or
** part of the body.  The header and body are accumulated in separate
** Blob structures then output sequentially once everything has been
** built.

      }
      zName = 0;
      showBytes = 0;
    }else{
      nArg = tokenize_line(zLine, sizeof(azArg)/sizeof(azArg[0]), azArg);
      for(i=0; i<nArg; i++){
        int c = tolower(azArg[i][0]);
        int n = strlen(azArg[i]);
        if( c=='c' && sqlite3_strnicmp(azArg[i],"content-disposition:",n)==0 ){
          i++;
        }else if( c=='n' && sqlite3_strnicmp(azArg[i],"name=",n)==0 ){
          zName = azArg[++i];
        }else if( c=='f' && sqlite3_strnicmp(azArg[i],"filename=",n)==0 ){
          char *z = azArg[++i];
          if( zName && z && islower(zName[0]) ){
            cgi_set_parameter_nocopy(mprintf("%s:filename",zName), z);
          }
          showBytes = 1;
        }else if( c=='c' && sqlite3_strnicmp(azArg[i],"content-type:",n)==0 ){
          char *z = azArg[++i];
          if( zName && z && islower(zName[0]) ){
            cgi_set_parameter_nocopy(mprintf("%s:mimetype",zName), z);
          }
        }
      }
    }

	./translate $(SRCDIR)/zip.c >zip_.c

zip.o:	zip_.c zip.h  $(SRCDIR)/config.h
	$(XTCC) -o zip.o -c zip_.c

zip.h:	headers
sqlite3.o:	$(SRCDIR)/sqlite3.c
	$(XTCC) -DSQLITE_OMIT_LOAD_EXTENSION=1 -DSQLITE_THREADSAFE=0 -DSQLITE_DEFAULT_FILE_FORMAT=4 -Dlocaltime=fossil_localtime -c $(SRCDIR)/sqlite3.c -o sqlite3.o

th.o:	$(SRCDIR)/th.c
	$(XTCC) -I$(SRCDIR) -c $(SRCDIR)/th.c -o th.o

th_lang.o:	$(SRCDIR)/th_lang.c
	$(XTCC) -I$(SRCDIR) -c $(SRCDIR)/th_lang.c -o th_lang.o

  puts "$s.h:\theaders"
#  puts "\t./makeheaders $mhargs\n\ttouch headers\n"
#  puts "\t./makeheaders ${s}_.c:${s}.h\n"
}


puts "sqlite3.o:\t\$(SRCDIR)/sqlite3.c"
set opt {-DSQLITE_OMIT_LOAD_EXTENSION=1}
append opt " -DSQLITE_THREADSAFE=0 -DSQLITE_DEFAULT_FILE_FORMAT=4"
#append opt " -DSQLITE_ENABLE_FTS3=1"
append opt " -Dlocaltime=fossil_localtime"
puts "\t\$(XTCC) $opt -c \$(SRCDIR)/sqlite3.c -o sqlite3.o\n"

puts "th.o:\t\$(SRCDIR)/th.c"
puts "\t\$(XTCC) -I\$(SRCDIR) -c \$(SRCDIR)/th.c -o th.o\n"

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.6.18.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a one translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% are more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other
** programs, you need this file and the "sqlite3.h" header file that defines
** the programming interface to the SQLite library.  (If you do not have 
** the "sqlite3.h" header file at hand, you will find a copy embedded within
** the text of this file.  Search for "Begin file sqlite3.h" to find the start
** of the embedded sqlite3.h header file.) Additional code files may be needed
** if you want a wrapper to interface SQLite with your choice of programming
** language. The code for the "sqlite3" command-line shell is also in a
** separate file. This file contains only code for the core SQLite library.
**
** This amalgamation was generated on 2009-09-09 16:11:06 UTC.
*/
#define SQLITE_CORE 1
#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
#ifndef SQLITE_API

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**

*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on POSIX if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
** system #includes.  Hence, this block of code must be the very first
** code in all source files.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: Red Hat 7.2) but you want your code to work
** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#ifdef _HAVE_SQLITE_CONFIG_H
#include "config.h"
#endif

** Maximum length (in bytes) of the pattern in a LIKE or GLOB
** operator.
*/
#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
#endif

/*
** Maximum depth of recursion for triggers.
*/
#ifndef SQLITE_MAX_TRIGGER_DEPTH
# define SQLITE_MAX_TRIGGER_DEPTH 1000
#endif

/************** End of sqliteLimit.h *****************************************/
/************** Continuing where we left off in sqliteInt.h ******************/

/* Disable nuisance warnings on Borland compilers */
#if defined(__BORLANDC__)
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */

*/
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#define SQLITE_INDEX_SAMPLES 10

/*
** This macro is used to "hide" some ugliness in casting an int
** value to a ptr value under the MSVC 64-bit compiler.   Casting
** non 64-bit values to ptr types results in a "hard" error with 
** the MSVC 64-bit compiler which this attempts to avoid.  
**

#   define SQLITE_PTR_TO_INT(X)  ((int)(X))
# endif
#else
# define SQLITE_INT_TO_PTR(X)   ((void*)&((char*)0)[X])
# define SQLITE_PTR_TO_INT(X)   ((int)(((char*)X)-(char*)0))
#endif





























/*
** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
** Older versions of SQLite used an optional THREADSAFE macro.
** We support that for legacy
*/
#if !defined(SQLITE_THREADSAFE)

** or constant definition does not appear in this file, then it is
** not a published API of SQLite, is subject to change without
** notice, and should not be referenced by programs that use SQLite.
**
** Some of the definitions that are in this file are marked as
** "experimental".  Experimental interfaces are normally new
** features recently added to SQLite.  We do not anticipate changes
** to experimental interfaces but reserve the right to make minor changes
** if experience from use "in the wild" suggest such changes are prudent.
**
** The official C-language API documentation for SQLite is derived
** from comments in this file.  This file is the authoritative source
** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.


*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

# define SQLITE_EXTERN extern
#endif

#ifndef SQLITE_API
# define SQLITE_API
#endif












/*
** These no-op macros are used in front of interfaces to mark those
** interfaces as either deprecated or experimental.  New applications
** should not use deprecated interfaces - they are support for backwards
** compatibility only.  Application writers should be aware that
** experimental interfaces are subject to change in point releases.
**
** These macros used to resolve to various kinds of compiler magic that
** would generate warning messages when they were used.  But that
** compiler magic ended up generating such a flurry of bug reports
** that we have taken it all out and gone back to using simple

/*
** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
**
** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
** the sqlite3.h file specify the version of SQLite with which
** that header file is associated.
**
** The "version" of SQLite is a string of the form "W.X.Y" or "W.X.Y.Z".

** The W value is major version number and is always 3 in SQLite3.
** The W value only changes when backwards compatibility is
** broken and we intend to never break backwards compatibility.
** The X value is the minor version number and only changes when
** there are major feature enhancements that are forwards compatible
** but not backwards compatible.
** The Y value is the release number and is incremented with
** each release but resets back to 0 whenever X is incremented.
** The Z value only appears on branch releases.
**
** The SQLITE_VERSION_NUMBER is an integer that is computed as
** follows:
**
** <blockquote><pre>
** SQLITE_VERSION_NUMBER = W*1000000 + X*1000 + Y
** </pre></blockquote>
**
** Since version 3.6.18, SQLite source code has been stored in the
** <a href="http://www.fossil-scm.org/">fossil configuration management
** system</a>.  The SQLITE_SOURCE_ID
** macro is a string which identifies a particular check-in of SQLite
** within its configuration management system.  The string contains the
** date and time of the check-in (UTC) and an SHA1 hash of the entire
** source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
**
** Requirements: [H10011] [H10014]
*/
#define SQLITE_VERSION        "3.6.18"
#define SQLITE_VERSION_NUMBER 3006018
#define SQLITE_SOURCE_ID      "2009-09-09 16:10:51 f0c72a53c5d57d7487b48a06a40816153f47aaac"

/*
** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
** KEYWORDS: sqlite3_version
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] #defines in the header,
** but are associated with the library instead of the header file.  Cautious
** programmers might include assert() statements in their application to
** verify that values returned by these interfaces match the macros in
** the header, and thus insure that the application is
** compiled with matching library and header files.
**
** <blockquote><pre>
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
** assert( strcmp(sqlite3_libversion,SQLITE_VERSION)==0 );
** </pre></blockquote>
**
** The sqlite3_libversion() function returns the same information as is
** in the sqlite3_version[] string constant.  The function is provided
** for use in DLLs since DLL users usually do not have direct access to string
** constants within the DLL.  Similarly, the sqlite3_sourceid() function
** returns the same information as is in the [SQLITE_SOURCE_ID] #define of
** the header file.
**
** See also: [sqlite_version()] and [sqlite_source_id()].
**
** Requirements: [H10021] [H10022] [H10023]
*/
SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
SQLITE_API const char *sqlite3_libversion(void);
SQLITE_API const char *sqlite3_sourceid(void);
SQLITE_API int sqlite3_libversion_number(void);

/*
** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
**
** SQLite can be compiled with or without mutexes.  When
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
** are enabled and SQLite is threadsafe.  When the
** [SQLITE_THREADSAFE] macro is 0, 
** the mutexes are omitted.  Without the mutexes, it is not safe
** to use SQLite concurrently from more than one thread.
**
** Enabling mutexes incurs a measurable performance penalty.
** So if speed is of utmost importance, it makes sense to disable
** the mutexes.  But for maximum safety, mutexes should be enabled.
** The default behavior is for mutexes to be enabled.
**
** This interface can be used by an application to make sure that the
** version of SQLite that it is linking against was compiled with
** the desired setting of the [SQLITE_THREADSAFE] macro.
**
** This interface only reports on the compile-time mutex setting
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
** can be fully or partially disabled using a call to [sqlite3_config()]
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
** or [SQLITE_CONFIG_MUTEX].  The return value of this function shows
** only the default compile-time setting, not any run-time changes
** to that setting.
**
** See the [threading mode] documentation for additional information.
**
** Requirements: [H10101] [H10102]
*/
SQLITE_API int sqlite3_threadsafe(void);

/*
** CAPI3REF: Database Connection Handle {H12000} <S40200>
** KEYWORDS: {database connection} {database connections}
**
** Each open SQLite database is represented by a pointer to an instance of
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3

** pointer or an [sqlite3] object pointer obtained
** from [sqlite3_open()], [sqlite3_open16()], or
** [sqlite3_open_v2()], and not previously closed.
**
** Requirements:
** [H12011] [H12012] [H12013] [H12014] [H12015] [H12019]
*/
SQLITE_API int sqlite3_close(sqlite3 *);

/*
** The type for a callback function.
** This is legacy and deprecated.  It is included for historical
** compatibility and is not documented.
*/
typedef int (*sqlite3_callback)(void*,int,char**, char**);

** The SQL statement text in the 2nd parameter to [sqlite3_exec()]
** must remain unchanged while [sqlite3_exec()] is running.
**
** Requirements:
** [H12101] [H12102] [H12104] [H12105] [H12107] [H12110] [H12113] [H12116]
** [H12119] [H12122] [H12125] [H12131] [H12134] [H12137] [H12138]
*/
SQLITE_API int sqlite3_exec(
  sqlite3*,                                  /* An open database */
  const char *sql,                           /* SQL to be evaluated */
  int (*callback)(void*,int,char**,char**),  /* Callback function */
  void *,                                    /* 1st argument to callback */
  char **errmsg                              /* Error msg written here */
);

#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */

/*
** CAPI3REF: Device Characteristics {H10240} <H11120>
**
** The xDeviceCapabilities method of the [sqlite3_io_methods]
** object returns an integer which is a vector of the these
** bit values expressing I/O characteristics of the mass storage

#define SQLITE_SYNC_NORMAL        0x00002
#define SQLITE_SYNC_FULL          0x00003
#define SQLITE_SYNC_DATAONLY      0x00010

/*
** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
**
** An [sqlite3_file] object represents an open file in the 
** [sqlite3_vfs | OS interface layer].  Individual OS interface
** implementations will
** want to subclass this object by appending additional fields
** for their own use.  The pMethods entry is a pointer to an
** [sqlite3_io_methods] object that defines methods for performing
** I/O operations on the open file.
*/
typedef struct sqlite3_file sqlite3_file;
struct sqlite3_file {

**
** The application should never invoke either sqlite3_os_init()
** or sqlite3_os_end() directly.  The application should only invoke
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
** interface is called automatically by sqlite3_initialize() and
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
** implementations for sqlite3_os_init() and sqlite3_os_end()
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
** When [custom builds | built for other platforms]
** (using the [SQLITE_OS_OTHER=1] compile-time
** option) the application must supply a suitable implementation for
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
** implementation of sqlite3_os_init() or sqlite3_os_end()
** must return [SQLITE_OK] on success and some other [error code] upon
** failure.
*/
SQLITE_API int sqlite3_initialize(void);
SQLITE_API int sqlite3_shutdown(void);
SQLITE_API int sqlite3_os_init(void);
SQLITE_API int sqlite3_os_end(void);

/*
** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
** EXPERIMENTAL
**
** The sqlite3_config() interface is used to make global configuration
** changes to SQLite in order to tune SQLite to the specific needs of

** then this routine returns a non-zero [error code].
**
** Requirements:
** [H14103] [H14106] [H14120] [H14123] [H14126] [H14129] [H14132] [H14135]
** [H14138] [H14141] [H14144] [H14147] [H14150] [H14153] [H14156] [H14159]
** [H14162] [H14165] [H14168]
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);

/*
** CAPI3REF: Configure database connections  {H14200} <S20000>
** EXPERIMENTAL
**
** The sqlite3_db_config() interface is used to make configuration
** changes to a [database connection].  The interface is similar to

** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
** New verbs are likely to be added in future releases of SQLite.
** Additional arguments depend on the verb.
**
** Requirements:
** [H14203] [H14206] [H14209] [H14212] [H14215]
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);

/*
** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
** EXPERIMENTAL
**
** An instance of this object defines the interface between SQLite
** and low-level memory allocation routines.
**
** This object is used in only one place in the SQLite interface.
** A pointer to an instance of this object is the argument to
** [sqlite3_config()] when the configuration option is
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
** By creating an instance of this object
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
** during configuration, an application can specify an alternative
** memory allocation subsystem for SQLite to use for all of its
** dynamic memory needs.
**
** Note that SQLite comes with several [built-in memory allocators]
** that are perfectly adequate for the overwhelming majority of applications
** and that this object is only useful to a tiny minority of applications
** with specialized memory allocation requirements.  This object is
** also used during testing of SQLite in order to specify an alternative
** memory allocator that simulates memory out-of-memory conditions in
** order to verify that SQLite recovers gracefully from such
** conditions.
**
** The xMalloc and xFree methods must work like the
** malloc() and free() functions from the standard C library.
** The xRealloc method must work like realloc() from the standard C library
** with the exception that if the second argument to xRealloc is zero,
** xRealloc must be a no-op - it must not perform any allocation or
** deallocation.  SQLite guaranteeds that the second argument to
** xRealloc is always a value returned by a prior call to xRoundup.
** And so in cases where xRoundup always returns a positive number,
** xRealloc can perform exactly as the standard library realloc() and
** still be in compliance with this specification.
**
** xSize should return the allocated size of a memory allocation
** previously obtained from xMalloc or xRealloc.  The allocated size
** is always at least as big as the requested size but may be larger.
**
** The xRoundup method returns what would be the allocated size of
** a memory allocation given a particular requested size.  Most memory
** allocators round up memory allocations at least to the next multiple
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
** Every memory allocation request coming in through [sqlite3_malloc()]
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
** that causes the corresponding memory allocation to fail.
**
** The xInit method initializes the memory allocator.  (For example,
** it might allocate any require mutexes or initialize internal data
** structures.  The xShutdown method is invoked (indirectly) by
** [sqlite3_shutdown()] and should deallocate any resources acquired
** by xInit.  The pAppData pointer is used as the only parameter to
** xInit and xShutdown.
**
** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
** the xInit method, so the xInit method need not be threadsafe.  The
** xShutdown method is only called from [sqlite3_shutdown()] so it does
** not need to be threadsafe either.  For all other methods, SQLite
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
** it is by default) and so the methods are automatically serialized.
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
** methods must be threadsafe or else make their own arrangements for
** serialization.
**
** SQLite will never invoke xInit() more than once without an intervening
** call to xShutdown().
*/
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
struct sqlite3_mem_methods {
  void *(*xMalloc)(int);         /* Memory allocation function */
  void (*xFree)(void*);          /* Free a prior allocation */
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
  int (*xSize)(void*);           /* Return the size of an allocation */

** structure is filled with the currently defined mutex routines.
** This option can be used to overload the default mutex allocation
** routines with a wrapper used to track mutex usage for performance
** profiling or testing, for example.</dd>
**
** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
** <dd>This option takes two arguments that determine the default
** memory allocation lookaside optimization.  The first argument is the
** size of each lookaside buffer slot and the second is the number of
** slots allocated to each database connection.  This option sets the
** <i>default</i> lookaside size.  The [SQLITE_DBCONFIG_LOOKASIDE]
** verb to [sqlite3_db_config()] can be used to change the lookaside
** configuration on individual connections.</dd>
**
** <dt>SQLITE_CONFIG_PCACHE</dt>
** <dd>This option takes a single argument which is a pointer to
** an [sqlite3_pcache_methods] object.  This object specifies the interface
** to a custom page cache implementation.  SQLite makes a copy of the
** object and uses it for page cache memory allocations.</dd>
**

** is invoked.
**
** <dl>
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
** <dd>This option takes three additional arguments that determine the 
** [lookaside memory allocator] configuration for the [database connection].
** The first argument (the third parameter to [sqlite3_db_config()] is a
** pointer to an memory buffer to use for lookaside memory.
** The first argument may be NULL in which case SQLite will allocate the
** lookaside buffer itself using [sqlite3_malloc()].  The second argument is the
** size of each lookaside buffer slot and the third argument is the number of
** slots.  The size of the buffer in the first argument must be greater than
** or equal to the product of the second and third arguments.  The buffer
** must be aligned to an 8-byte boundary.  If the second argument is not
** a multiple of 8, it is internally rounded down to the next smaller
** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_LOOKASIDE    1001  /* void* int int */


/*
** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
**
** The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. The extended result
** codes are disabled by default for historical compatibility considerations.
**
** Requirements:
** [H12201] [H12202]
*/
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);

/*
** CAPI3REF: Last Insert Rowid {H12220} <S10700>
**
** Each entry in an SQLite table has a unique 64-bit signed
** integer key called the [ROWID | "rowid"]. The rowid is always available
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those

** If a separate thread performs a new [INSERT] on the same
** database connection while the [sqlite3_last_insert_rowid()]
** function is running and thus changes the last insert [rowid],
** then the value returned by [sqlite3_last_insert_rowid()] is
** unpredictable and might not equal either the old or the new
** last insert [rowid].
*/
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);

/*
** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
**
** This function returns the number of database rows that were changed
** or inserted or deleted by the most recently completed SQL statement
** on the [database connection] specified by the first parameter.

** Requirements:
** [H12241] [H12243]
**
** If a separate thread makes changes on the same database connection
** while [sqlite3_changes()] is running then the value returned
** is unpredictable and not meaningful.
*/
SQLITE_API int sqlite3_changes(sqlite3*);

/*
** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
**
** This function returns the number of row changes caused by [INSERT],
** [UPDATE] or [DELETE] statements since the [database connection] was opened.
** The count includes all changes from all 

** Requirements:
** [H12261] [H12263]
**
** If a separate thread makes changes on the same database connection
** while [sqlite3_total_changes()] is running then the value
** returned is unpredictable and not meaningful.
*/
SQLITE_API int sqlite3_total_changes(sqlite3*);

/*
** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
**
** This function causes any pending database operation to abort and
** return at its earliest opportunity. This routine is typically
** called in response to a user action such as pressing "Cancel"

**
** Requirements:
** [H12271] [H12272]
**
** If the database connection closes while [sqlite3_interrupt()]
** is running then bad things will likely happen.
*/
SQLITE_API void sqlite3_interrupt(sqlite3*);

/*
** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
**
** These routines are useful during command-line input to determine if the
** currently entered text seems to form a complete SQL statement or
** if additional input is needed before sending the text into

**
** The input to [sqlite3_complete()] must be a zero-terminated
** UTF-8 string.
**
** The input to [sqlite3_complete16()] must be a zero-terminated
** UTF-16 string in native byte order.
*/
SQLITE_API int sqlite3_complete(const char *sql);
SQLITE_API int sqlite3_complete16(const void *sql);

/*
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
**
** This routine sets a callback function that might be invoked whenever
** an attempt is made to open a database table that another thread
** or process has locked.

** 
** Requirements:
** [H12311] [H12312] [H12314] [H12316] [H12318]
**
** A busy handler must not close the database connection
** or [prepared statement] that invoked the busy handler.
*/
SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);

/*
** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
**
** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
** for a specified amount of time when a table is locked.  The handler
** will sleep multiple times until at least "ms" milliseconds of sleeping

** [database connection] any any given moment.  If another busy handler
** was defined  (using [sqlite3_busy_handler()]) prior to calling
** this routine, that other busy handler is cleared.
**
** Requirements:
** [H12341] [H12343] [H12344]
*/
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);

/*
** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
**
** Definition: A <b>result table</b> is memory data structure created by the
** [sqlite3_get_table()] interface.  A result table records the
** complete query results from one or more queries.

** interface defined here.  As a consequence, errors that occur in the
** wrapper layer outside of the internal [sqlite3_exec()] call are not
** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
**
** Requirements:
** [H12371] [H12373] [H12374] [H12376] [H12379] [H12382]
*/
SQLITE_API int sqlite3_get_table(
  sqlite3 *db,          /* An open database */
  const char *zSql,     /* SQL to be evaluated */
  char ***pazResult,    /* Results of the query */
  int *pnRow,           /* Number of result rows written here */
  int *pnColumn,        /* Number of result columns written here */
  char **pzErrmsg       /* Error msg written here */
);
SQLITE_API void sqlite3_free_table(char **result);

/*
** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
**
** These routines are work-alikes of the "printf()" family of functions
** from the standard C library.
**
** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
** results into memory obtained from [sqlite3_malloc()].
** The strings returned by these two routines should be
** released by [sqlite3_free()].  Both routines return a
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough

** The "%z" formatting option works exactly like "%s" with the
** addition that after the string has been read and copied into
** the result, [sqlite3_free()] is called on the input string. {END}
**
** Requirements:
** [H17403] [H17406] [H17407]
*/
SQLITE_API char *sqlite3_mprintf(const char*,...);
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);

/*
** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
**
** The SQLite core  uses these three routines for all of its own
** internal memory allocation needs. "Core" in the previous sentence
** does not include operating-system specific VFS implementation.  The

** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
** not yet been released.
**
** The application must not read or write any part of
** a block of memory after it has been released using
** [sqlite3_free()] or [sqlite3_realloc()].
*/
SQLITE_API void *sqlite3_malloc(int);
SQLITE_API void *sqlite3_realloc(void*, int);
SQLITE_API void sqlite3_free(void*);

/*
** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
**
** SQLite provides these two interfaces for reporting on the status
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
** routines, which form the built-in memory allocation subsystem.
**
** Requirements:
** [H17371] [H17373] [H17374] [H17375]
*/
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);

/*
** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
**
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
** select random [ROWID | ROWIDs] when inserting new records into a table that
** already uses the largest possible [ROWID].  The PRNG is also used for

** On all subsequent invocations, the pseudo-randomness is generated
** internally and without recourse to the [sqlite3_vfs] xRandomness
** method.
**
** Requirements:
** [H17392]
*/
SQLITE_API void sqlite3_randomness(int N, void *P);

/*
** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
**
** This routine registers a authorizer callback with a particular
** [database connection], supplied in the first argument.
** The authorizer callback is invoked as SQL statements are being compiled

**
** The authorizer callback must not do anything that will modify
** the database connection that invoked the authorizer callback.
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
** database connections for the meaning of "modify" in this paragraph.
**
** When [sqlite3_prepare_v2()] is used to prepare a statement, the
** statement might be re-prepared during [sqlite3_step()] due to a 
** schema change.  Hence, the application should ensure that the
** correct authorizer callback remains in place during the [sqlite3_step()].
**
** Note that the authorizer callback is invoked only during
** [sqlite3_prepare()] or its variants.  Authorization is not
** performed during statement evaluation in [sqlite3_step()], unless
** as stated in the previous paragraph, sqlite3_step() invokes
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
**
** Requirements:
** [H12501] [H12502] [H12503] [H12504] [H12505] [H12506] [H12507] [H12510]
** [H12511] [H12512] [H12520] [H12521] [H12522]
*/
SQLITE_API int sqlite3_set_authorizer(
  sqlite3*,
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
  void *pUserData
);

/*
** CAPI3REF: Authorizer Return Codes {H12590} <H12500>

** the original statement text and an estimate of wall-clock time
** of how long that statement took to run.
**
** Requirements:
** [H12281] [H12282] [H12283] [H12284] [H12285] [H12287] [H12288] [H12289]
** [H12290]
*/
SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);

/*
** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
**
** This routine configures a callback function - the
** progress callback - that is invoked periodically during long

** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
** database connections for the meaning of "modify" in this paragraph.
**
** Requirements:
** [H12911] [H12912] [H12913] [H12914] [H12915] [H12916] [H12917] [H12918]
**
*/
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);

/*
** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
**
** These routines open an SQLite database file whose name is given by the
** filename argument. The filename argument is interpreted as UTF-8 for
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte

** associated with the [database connection] handle should be released by
** passing it to [sqlite3_close()] when it is no longer required.
**
** The sqlite3_open_v2() interface works like sqlite3_open()
** except that it accepts two additional parameters for additional control
** over the new database connection.  The flags parameter can take one of
** the following three values, optionally combined with the 
** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
** and/or [SQLITE_OPEN_PRIVATECACHE] flags:
**
** <dl>
** <dt>[SQLITE_OPEN_READONLY]</dt>
** <dd>The database is opened in read-only mode.  If the database does not
** already exist, an error is returned.</dd>
**
** <dt>[SQLITE_OPEN_READWRITE]</dt>
** <dd>The database is opened for reading and writing if possible, or reading
** only if the file is write protected by the operating system.  In either
** case the database must already exist, otherwise an error is returned.</dd>
**
** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
** <dd>The database is opened for reading and writing, and is creates it if
** it does not already exist. This is the behavior that is always used for
** sqlite3_open() and sqlite3_open16().</dd>
** </dl>
**
** If the 3rd parameter to sqlite3_open_v2() is not one of the
** combinations shown above or one of the combinations shown above combined
** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
** then the behavior is undefined.
**
** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
** opens in the multi-thread [threading mode] as long as the single-thread
** mode has not been set at compile-time or start-time.  If the
** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
** in the serialized [threading mode] unless single-thread was
** previously selected at compile-time or start-time.
** The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
** eligible to use [shared cache mode], regardless of whether or not shared
** cache is enabled using [sqlite3_enable_shared_cache()].  The
** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
** participate in [shared cache mode] even if it is enabled.
**
** If the filename is ":memory:", then a private, temporary in-memory database
** is created for the connection.  This in-memory database will vanish when
** the database connection is closed.  Future versions of SQLite might
** make use of additional special filenames that begin with the ":" character.
** It is recommended that when a database filename actually does begin with
** a ":" character you should prefix the filename with a pathname such as

** characters must be converted to UTF-8 prior to passing them into
** sqlite3_open() or sqlite3_open_v2().
**
** Requirements:
** [H12701] [H12702] [H12703] [H12704] [H12706] [H12707] [H12709] [H12711]
** [H12712] [H12713] [H12714] [H12717] [H12719] [H12721] [H12723]
*/
SQLITE_API int sqlite3_open(
  const char *filename,   /* Database filename (UTF-8) */
  sqlite3 **ppDb          /* OUT: SQLite db handle */
);
SQLITE_API int sqlite3_open16(
  const void *filename,   /* Database filename (UTF-16) */
  sqlite3 **ppDb          /* OUT: SQLite db handle */
);
SQLITE_API int sqlite3_open_v2(
  const char *filename,   /* Database filename (UTF-8) */
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
  int flags,              /* Flags */
  const char *zVfs        /* Name of VFS module to use */
);

/*

** If an interface fails with SQLITE_MISUSE, that means the interface
** was invoked incorrectly by the application.  In that case, the
** error code and message may or may not be set.
**
** Requirements:
** [H12801] [H12802] [H12803] [H12807] [H12808] [H12809]
*/
SQLITE_API int sqlite3_errcode(sqlite3 *db);
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);

/*
** CAPI3REF: SQL Statement Object {H13000} <H13010>
** KEYWORDS: {prepared statement} {prepared statements}
**
** An instance of this object represents a single SQL statement.
** This object is variously known as a "prepared statement" or a

** [max_page_count] [PRAGMA].
**
** New run-time limit categories may be added in future releases.
**
** Requirements:
** [H12762] [H12766] [H12769]
*/
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);

/*
** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
** KEYWORDS: {limit category} {limit categories}
**
** These constants define various performance limits
** that can be lowered at run-time using [sqlite3_limit()].

** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
** <dd>The maximum length of the pattern argument to the [LIKE] or
** [GLOB] operators.</dd>
**
** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
** <dd>The maximum number of variables in an SQL statement that can
** be bound.</dd>
**
** <dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
** <dd>The maximum depth of recursion for triggers.</dd>
** </dl>
*/
#define SQLITE_LIMIT_LENGTH                    0
#define SQLITE_LIMIT_SQL_LENGTH                1
#define SQLITE_LIMIT_COLUMN                    2
#define SQLITE_LIMIT_EXPR_DEPTH                3
#define SQLITE_LIMIT_COMPOUND_SELECT           4
#define SQLITE_LIMIT_VDBE_OP                   5
#define SQLITE_LIMIT_FUNCTION_ARG              6
#define SQLITE_LIMIT_ATTACHED                  7
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
#define SQLITE_LIMIT_TRIGGER_DEPTH            10

/*
** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
** KEYWORDS: {SQL statement compiler}
**
** To execute an SQL query, it must first be compiled into a byte-code
** program using one of these routines.

** </li>
** </ol>
**
** Requirements:
** [H13011] [H13012] [H13013] [H13014] [H13015] [H13016] [H13019] [H13021]
**
*/
SQLITE_API int sqlite3_prepare(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare_v2(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare16(
  sqlite3 *db,            /* Database handle */
  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare16_v2(
  sqlite3 *db,            /* Database handle */
  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);

/*
** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
**
** This interface can be used to retrieve a saved copy of the original
** SQL text used to create a [prepared statement] if that statement was
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
**
** Requirements:
** [H13101] [H13102] [H13103]
*/
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
**
** SQLite uses the sqlite3_value object to represent all values
** that can be stored in a database table. SQLite uses dynamic typing

/*
** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
**
** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
** literals may be replaced by a [parameter] that matches one of following
** templates:
**
** <ul>
** <li>  ?
** <li>  ?NNN
** <li>  :VVV
** <li>  @VVV
** <li>  $VVV
** </ul>
**
** In the templates above, NNN represents an integer literal,
** and VVV represents an alphanumeric identifer.  The values of these
** parameters (also called "host parameter names" or "SQL parameters")
** can be set using the sqlite3_bind_*() routines defined here.
**
** The first argument to the sqlite3_bind_*() routines is always
** a pointer to the [sqlite3_stmt] object returned from
** [sqlite3_prepare_v2()] or its variants.
**

** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
**
** Requirements:
** [H13506] [H13509] [H13512] [H13515] [H13518] [H13521] [H13524] [H13527]
** [H13530] [H13533] [H13536] [H13539] [H13542] [H13545] [H13548] [H13551]
**
*/
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);

/*
** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
**
** This routine can be used to find the number of [SQL parameters]
** in a [prepared statement].  SQL parameters are tokens of the
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as

** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_name()], and
** [sqlite3_bind_parameter_index()].
**
** Requirements:
** [H13601]
*/
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);

/*
** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
**
** This routine returns a pointer to the name of the n-th
** [SQL parameter] in a [prepared statement].
** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"

** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
**
** Requirements:
** [H13621]
*/
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);

/*
** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
**
** Return the index of an SQL parameter given its name.  The
** index value returned is suitable for use as the second
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  A zero
** is returned if no matching parameter is found.  The parameter
** name must be given in UTF-8 even if the original statement
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
**
** Requirements:
** [H13641]
*/
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);

/*
** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
**
** Contrary to the intuition of many, [sqlite3_reset()] does not reset
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
** Use this routine to reset all host parameters to NULL.
**
** Requirements:
** [H13661]
*/
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);

/*
** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
**
** Return the number of columns in the result set returned by the
** [prepared statement]. This routine returns 0 if pStmt is an SQL
** statement that does not return data (for example an [UPDATE]).
**
** Requirements:
** [H13711]
*/
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
**
** These routines return the name assigned to a particular column
** in the result set of a [SELECT] statement.  The sqlite3_column_name()
** interface returns a pointer to a zero-terminated UTF-8 string

** that column, if there is an AS clause.  If there is no AS clause
** then the name of the column is unspecified and may change from
** one release of SQLite to the next.
**
** Requirements:
** [H13721] [H13723] [H13724] [H13725] [H13726] [H13727]
*/
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);

/*
** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
**
** These routines provide a means to determine what column of what
** table in which database a result of a [SELECT] statement comes from.
** The name of the database or table or column can be returned as

** [H13741] [H13742] [H13743] [H13744] [H13745] [H13746] [H13748]
**
** If two or more threads call one or more
** [sqlite3_column_database_name | column metadata interfaces]
** for the same [prepared statement] and result column
** at the same time then the results are undefined.
*/
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);

/*
** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
**
** The first parameter is a [prepared statement].
** If this statement is a [SELECT] statement and the Nth column of the
** returned result set of that [SELECT] is a table column (not an

** strongly typed, but the typing is dynamic not static.  Type
** is associated with individual values, not with the containers
** used to hold those values.
**
** Requirements:
** [H13761] [H13762] [H13763]
*/
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);

/*
** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
**
** After a [prepared statement] has been prepared using either
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function

** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
** then the more specific [error codes] are returned directly
** by sqlite3_step().  The use of the "v2" interface is recommended.
**
** Requirements:
** [H13202] [H15304] [H15306] [H15308] [H15310]
*/
SQLITE_API int sqlite3_step(sqlite3_stmt*);

/*
** CAPI3REF: Number of columns in a result set {H13770} <S10700>
**
** Returns the number of values in the current row of the result set.
**
** Requirements:
** [H13771] [H13772]
*/
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
** KEYWORDS: SQLITE_TEXT
**
** {H10266} Every value in SQLite has one of five fundamental datatypes:
**

** pointer.  Subsequent calls to [sqlite3_errcode()] will return
** [SQLITE_NOMEM].
**
** Requirements:
** [H13803] [H13806] [H13809] [H13812] [H13815] [H13818] [H13821] [H13824]
** [H13827] [H13830]
*/
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);

/*
** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
**
** The sqlite3_finalize() function is called to delete a [prepared statement].
** If the statement was executed successfully or not executed at all, then
** SQLITE_OK is returned. If execution of the statement failed then an
** [error code] or [extended error code] is returned.
**
** This routine can be called at any point during the execution of the
** [prepared statement].  If the virtual machine has not
** completed execution when this routine is called, that is like
** encountering an error or an [sqlite3_interrupt | interrupt].
** Incomplete updates may be rolled back and transactions canceled,
** depending on the circumstances, and the
** [error code] returned will be [SQLITE_ABORT].
**
** Requirements:
** [H11302] [H11304]
*/
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
**
** The sqlite3_reset() function is called to reset a [prepared statement]
** object back to its initial state, ready to be re-executed.
** Any SQL statement variables that had values bound to them using

** {H11336} If the most recent call to [sqlite3_step(S)] for the
**          [prepared statement] S indicated an error, then
**          [sqlite3_reset(S)] returns an appropriate [error code].
**
** {H11338} The [sqlite3_reset(S)] interface does not change the values
**          of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
*/
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
** KEYWORDS: {function creation routines}
** KEYWORDS: {application-defined SQL function}
** KEYWORDS: {application-defined SQL functions}
**

** parameter is less than -1 or greater than 127 then the behavior is
** undefined.
**
** The fourth parameter, eTextRep, specifies what
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
** its parameters.  Any SQL function implementation should be able to work
** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
** more efficient with one encoding than another.  An application may
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
** times with the same function but with different values of eTextRep.
** When multiple implementations of the same function are available, SQLite
** will pick the one that involves the least amount of data conversion.
** If there is only a single implementation which does not care what text
** encoding is used, then the fourth argument should be [SQLITE_ANY].
**

** parameters. An aggregate SQL function requires an implementation of xStep
** and xFinal and NULL should be passed for xFunc. To delete an existing
** SQL function or aggregate, pass NULL for all three function callbacks.
**
** It is permitted to register multiple implementations of the same
** functions with the same name but with either differing numbers of
** arguments or differing preferred text encodings.  SQLite will use
** the implementation that most closely matches the way in which the
** SQL function is used.  A function implementation with a non-negative
** nArg parameter is a better match than a function implementation with
** a negative nArg.  A function where the preferred text encoding
** matches the database encoding is a better
** match than a function where the encoding is different.  
** A function where the encoding difference is between UTF16le and UTF16be
** is a closer match than a function where the encoding difference is

** close the database connection nor finalize or reset the prepared
** statement in which the function is running.
**
** Requirements:
** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127]
** [H16130] [H16133] [H16136] [H16139] [H16142]
*/
SQLITE_API int sqlite3_create_function(
  sqlite3 *db,
  const char *zFunctionName,
  int nArg,
  int eTextRep,
  void *pApp,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  void (*xFinal)(sqlite3_context*)
);
SQLITE_API int sqlite3_create_function16(
  sqlite3 *db,
  const void *zFunctionName,
  int nArg,
  int eTextRep,
  void *pApp,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),

** These functions are [deprecated].  In order to maintain
** backwards compatibility with older code, these functions continue 
** to be supported.  However, new applications should avoid
** the use of these functions.  To help encourage people to avoid
** using these functions, we are not going to tell you what they do.
*/
#ifndef SQLITE_OMIT_DEPRECATED
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
#endif

/*
** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
**
** The C-language implementation of SQL functions and aggregates uses
** this set of interface routines to access the parameter values on

** These routines must be called from the same thread as
** the SQL function that supplied the [sqlite3_value*] parameters.
**
** Requirements:
** [H15103] [H15106] [H15109] [H15112] [H15115] [H15118] [H15121] [H15124]
** [H15127] [H15130] [H15133] [H15136]
*/
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
SQLITE_API double sqlite3_value_double(sqlite3_value*);
SQLITE_API int sqlite3_value_int(sqlite3_value*);
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
SQLITE_API int sqlite3_value_type(sqlite3_value*);
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);

/*
** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
**
** The implementation of aggregate SQL functions use this routine to allocate
** a structure for storing their state.
**

**
** This routine must be called from the same thread in which
** the aggregate SQL function is running.
**
** Requirements:
** [H16211] [H16213] [H16215] [H16217]
*/
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);

/*
** CAPI3REF: User Data For Functions {H16240} <S20200>
**
** The sqlite3_user_data() interface returns a copy of
** the pointer that was the pUserData parameter (the 5th parameter)
** of the [sqlite3_create_function()]
** and [sqlite3_create_function16()] routines that originally
** registered the application defined function. {END}
**
** This routine must be called from the same thread in which
** the application-defined function is running.
**
** Requirements:
** [H16243]
*/
SQLITE_API void *sqlite3_user_data(sqlite3_context*);

/*
** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
**
** The sqlite3_context_db_handle() interface returns a copy of
** the pointer to the [database connection] (the 1st parameter)
** of the [sqlite3_create_function()]
** and [sqlite3_create_function16()] routines that originally
** registered the application defined function.
**
** Requirements:
** [H16253]
*/
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);

/*
** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
**
** The following two functions may be used by scalar SQL functions to
** associate metadata with argument values. If the same value is passed to
** multiple invocations of the same SQL function during query execution, under

**
** These routines must be called from the same thread in which
** the SQL function is running.
**
** Requirements:
** [H16272] [H16274] [H16276] [H16277] [H16278] [H16279]
*/
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));


/*
** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
**
** These are special values for the destructor that is passed in as the
** final argument to routines like [sqlite3_result_blob()].  If the destructor

** is non-negative, then as many bytes (not characters) of the text
** pointed to by the 2nd parameter are taken as the application-defined
** function result.
** If the 4th parameter to the sqlite3_result_text* interfaces
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
** function as the destructor on the text or BLOB result when it has
** finished using that result.
** If the 4th parameter to the sqlite3_result_text* interfaces or to
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
** assumes that the text or BLOB result is in constant space and does not
** copy the content of the parameter nor call a destructor on the content
** when it has finished using that result.
** If the 4th parameter to the sqlite3_result_text* interfaces
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
** then SQLite makes a copy of the result into space obtained from
** from [sqlite3_malloc()] before it returns.
**
** The sqlite3_result_value() interface sets the result of
** the application-defined function to be a copy the

** the [sqlite3_context] pointer, the results are undefined.
**
** Requirements:
** [H16403] [H16406] [H16409] [H16412] [H16415] [H16418] [H16421] [H16424]
** [H16427] [H16430] [H16433] [H16436] [H16439] [H16442] [H16445] [H16448]
** [H16451] [H16454] [H16457] [H16460] [H16463]
*/
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
SQLITE_API void sqlite3_result_null(sqlite3_context*);
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);

/*
** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
**
** These functions are used to add new collation sequences to the
** [database connection] specified as the first argument.
**

**
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
**
** Requirements:
** [H16603] [H16604] [H16606] [H16609] [H16612] [H16615] [H16618] [H16621]
** [H16624] [H16627] [H16630]
*/
SQLITE_API int sqlite3_create_collation(
  sqlite3*, 
  const char *zName, 
  int eTextRep, 
  void*,
  int(*xCompare)(void*,int,const void*,int,const void*)
);
SQLITE_API int sqlite3_create_collation_v2(
  sqlite3*, 
  const char *zName, 
  int eTextRep, 
  void*,
  int(*xCompare)(void*,int,const void*,int,const void*),
  void(*xDestroy)(void*)
);
SQLITE_API int sqlite3_create_collation16(
  sqlite3*, 
  const void *zName,
  int eTextRep, 
  void*,
  int(*xCompare)(void*,int,const void*,int,const void*)
);

** The callback function should register the desired collation using
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
** [sqlite3_create_collation_v2()].
**
** Requirements:
** [H16702] [H16704] [H16706]
*/
SQLITE_API int sqlite3_collation_needed(
  sqlite3*, 
  void*, 
  void(*)(void*,sqlite3*,int eTextRep,const char*)
);
SQLITE_API int sqlite3_collation_needed16(
  sqlite3*, 
  void*,
  void(*)(void*,sqlite3*,int eTextRep,const void*)
);

/*
** Specify the key for an encrypted database.  This routine should be
** called right after sqlite3_open().
**
** The code to implement this API is not available in the public release
** of SQLite.
*/
SQLITE_API int sqlite3_key(
  sqlite3 *db,                   /* Database to be rekeyed */
  const void *pKey, int nKey     /* The key */
);

/*
** Change the key on an open database.  If the current database is not
** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
** database is decrypted.
**
** The code to implement this API is not available in the public release
** of SQLite.
*/
SQLITE_API int sqlite3_rekey(
  sqlite3 *db,                   /* Database to be rekeyed */
  const void *pKey, int nKey     /* The new key */
);

/*
** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
**
** The sqlite3_sleep() function causes the current thread to suspend execution
** for at least a number of milliseconds specified in its parameter.
**
** If the operating system does not support sleep requests with
** millisecond time resolution, then the time will be rounded up to
** the nearest second. The number of milliseconds of sleep actually
** requested from the operating system is returned.
**
** SQLite implements this interface by calling the xSleep()
** method of the default [sqlite3_vfs] object.
**
** Requirements: [H10533] [H10536]
*/
SQLITE_API int sqlite3_sleep(int);

/*
** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
**
** If this global variable is made to point to a string which is
** the name of a folder (a.k.a. directory), then all temporary files
** created by SQLite will be placed in that directory.  If this variable

** that this variable points to is held in memory obtained from 
** [sqlite3_malloc] and the pragma may attempt to free that memory
** using [sqlite3_free].
** Hence, if this variable is modified directly, either it should be
** made NULL or made to point to memory obtained from [sqlite3_malloc]
** or else the use of the [temp_store_directory pragma] should be avoided.
*/
SQLITE_API char *sqlite3_temp_directory;

/*
** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
** KEYWORDS: {autocommit mode}
**
** The sqlite3_get_autocommit() interface returns non-zero or
** zero if the given database connection is or is not in autocommit mode,

**
** If another thread changes the autocommit status of the database
** connection while this routine is running, then the return value
** is undefined.
**
** Requirements: [H12931] [H12932] [H12933] [H12934]
*/
SQLITE_API int sqlite3_get_autocommit(sqlite3*);

/*
** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
**
** The sqlite3_db_handle interface returns the [database connection] handle
** to which a [prepared statement] belongs.  The [database connection]
** returned by sqlite3_db_handle is the same [database connection] that was the first argument
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
** create the statement in the first place.
**
** Requirements: [H13123]
*/
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);

/*
** CAPI3REF: Find the next prepared statement {H13140} <S60600>
**
** This interface returns a pointer to the next [prepared statement] after
** pStmt associated with the [database connection] pDb.  If pStmt is NULL
** then this interface returns a pointer to the first prepared statement
** associated with the database connection pDb.  If no prepared statement
** satisfies the conditions of this routine, it returns NULL.
**
** The [database connection] pointer D in a call to
** [sqlite3_next_stmt(D,S)] must refer to an open database
** connection and in particular must not be a NULL pointer.
**
** Requirements: [H13143] [H13146] [H13149] [H13152]
*/
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);

/*
** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
**
** The sqlite3_commit_hook() interface registers a callback
** function to be invoked whenever a transaction is [COMMIT | committed].
** Any callback set by a previous call to sqlite3_commit_hook()

**
** See also the [sqlite3_update_hook()] interface.
**
** Requirements:
** [H12951] [H12952] [H12953] [H12954] [H12955]
** [H12961] [H12962] [H12963] [H12964]
*/
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);

/*
** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
**
** The sqlite3_update_hook() interface registers a callback function
** with the [database connection] identified by the first argument
** to be invoked whenever a row is updated, inserted or deleted.

**
** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
** interfaces.
**
** Requirements:
** [H12971] [H12973] [H12975] [H12977] [H12979] [H12981] [H12983] [H12986]
*/
SQLITE_API void *sqlite3_update_hook(
  sqlite3*, 
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
  void*
);

/*
** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>

** future releases of SQLite.  Applications that care about shared
** cache setting should set it explicitly.
**
** See Also:  [SQLite Shared-Cache Mode]
**
** Requirements: [H10331] [H10336] [H10337] [H10339]
*/
SQLITE_API int sqlite3_enable_shared_cache(int);

/*
** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
**
** The sqlite3_release_memory() interface attempts to free N bytes
** of heap memory by deallocating non-essential memory allocations
** held by the database library. {END}  Memory used to cache database
** pages to improve performance is an example of non-essential memory.
** sqlite3_release_memory() returns the number of bytes actually freed,
** which might be more or less than the amount requested.
**
** Requirements: [H17341] [H17342]
*/
SQLITE_API int sqlite3_release_memory(int);

/*
** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
**
** The sqlite3_soft_heap_limit() interface places a "soft" limit
** on the amount of heap memory that may be allocated by SQLite.
** If an internal allocation is requested that would exceed the

** is an upper bound on the total memory allocation for all threads. In
** version 3.5.0 there is no mechanism for limiting the heap usage for
** individual threads.
**
** Requirements:
** [H16351] [H16352] [H16353] [H16354] [H16355] [H16358]
*/
SQLITE_API void sqlite3_soft_heap_limit(int);

/*
** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
**
** This routine returns metadata about a specific column of a specific
** database table accessible using the [database connection] handle
** passed as the first function argument.

** error occurs during this process, or if the requested table or column
** cannot be found, an [error code] is returned and an error message left
** in the [database connection] (to be retrieved using sqlite3_errmsg()).
**
** This API is only available if the library was compiled with the
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
*/
SQLITE_API int sqlite3_table_column_metadata(
  sqlite3 *db,                /* Connection handle */
  const char *zDbName,        /* Database name or NULL */
  const char *zTableName,     /* Table name */
  const char *zColumnName,    /* Column name */
  char const **pzDataType,    /* OUTPUT: Declared data type */
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */

**          obtained from [sqlite3_malloc()]. {END}  The calling function
**          should free this memory by calling [sqlite3_free()].
**
** {H12606} Extension loading must be enabled using
**          [sqlite3_enable_load_extension()] prior to calling this API,
**          otherwise an error will be returned.
*/
SQLITE_API int sqlite3_load_extension(
  sqlite3 *db,          /* Load the extension into this database connection */
  const char *zFile,    /* Name of the shared library containing extension */
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
  char **pzErrMsg       /* Put error message here if not 0 */
);

/*

**
** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
**          to turn extension loading on and call it with onoff==0 to turn
**          it back off again.
**
** {H12622} Extension loading is off by default.
*/
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);

/*
** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
**
** This API can be invoked at program startup in order to register
** one or more statically linked extensions that will be available
** to all new [database connections]. {END}

**          multiple times with the same extension is harmless.
**
** {H12643} This routine stores a pointer to the extension in an array
**          that is obtained from [sqlite3_malloc()].
**
** {H12644} Automatic extensions apply across all threads.
*/
SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));

/*
** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
**
** This function disables all previously registered automatic
** extensions. {END}  It undoes the effect of all prior
** [sqlite3_auto_extension()] calls.
**
** {H12661} This function disables all previously registered
**          automatic extensions.
**
** {H12662} This function disables automatic extensions in all threads.
*/
SQLITE_API void sqlite3_reset_auto_extension(void);

/*
****** EXPERIMENTAL - subject to change without notice **************
**
** The interface to the virtual-table mechanism is currently considered
** to be experimental.  The interface might change in incompatible ways.
** If this is a problem for you, do not use the interface at this time.

** parameter is an arbitrary client data pointer that is passed through
** into the [xCreate] and [xConnect] methods of the virtual table module
** when a new virtual table is be being created or reinitialized.
**
** This interface has exactly the same effect as calling
** [sqlite3_create_module_v2()] with a NULL client data destructor.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *p,   /* Methods for the module */
  void *pClientData          /* Client data for xCreate/xConnect */
);

/*
** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
** EXPERIMENTAL
**
** This routine is identical to the [sqlite3_create_module()] method,
** except that it has an extra parameter to specify 
** a destructor function for the client data pointer.  SQLite will
** invoke the destructor function (if it is not NULL) when SQLite
** no longer needs the pClientData pointer.  
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *p,   /* Methods for the module */
  void *pClientData,         /* Client data for xCreate/xConnect */
  void(*xDestroy)(void*)     /* Module destructor function */
);

** EXPERIMENTAL
**
** The [xCreate] and [xConnect] methods of a
** [virtual table module] call this interface
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zSQL);

/*
** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
** EXPERIMENTAL
**
** Virtual tables can provide alternative implementations of functions
** using the [xFindFunction] method of the [virtual table module].  
** But global versions of those functions
** must exist in order to be overloaded.
**
** This API makes sure a global version of a function with a particular
** name and number of parameters exists.  If no such function exists
** before this API is called, a new function is created.  The implementation
** of the new function always causes an exception to be thrown.  So
** the new function is not good for anything by itself.  Its only
** purpose is to be a placeholder function that can be overloaded
** by a [virtual table].
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);

/*
** The interface to the virtual-table mechanism defined above (back up
** to a comment remarkably similar to this one) is currently considered
** to be experimental.  The interface might change in incompatible ways.
** If this is a problem for you, do not use the interface at this time.
**

** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
** Changes written into a BLOB prior to the BLOB expiring are not
** rollback by the expiration of the BLOB.  Such changes will eventually
** commit if the transaction continues to completion.
**
** Use the [sqlite3_blob_bytes()] interface to determine the size of
** the opened blob.  The size of a blob may not be changed by this
** interface.  Use the [UPDATE] SQL command to change the size of a
** blob.
**
** The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
** and the built-in [zeroblob] SQL function can be used, if desired,
** to create an empty, zero-filled blob in which to read or write using
** this interface.
**
** To avoid a resource leak, every open [BLOB handle] should eventually
** be released by a call to [sqlite3_blob_close()].
**
** Requirements:
** [H17813] [H17814] [H17816] [H17819] [H17821] [H17824]
*/
SQLITE_API int sqlite3_blob_open(
  sqlite3*,
  const char *zDb,
  const char *zTable,
  const char *zColumn,
  sqlite3_int64 iRow,
  int flags,
  sqlite3_blob **ppBlob

**
** Calling this routine with a null pointer (which as would be returned
** by failed call to [sqlite3_blob_open()]) is a harmless no-op.
**
** Requirements:
** [H17833] [H17836] [H17839]
*/
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);

/*
** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
**
** Returns the size in bytes of the BLOB accessible via the 
** successfully opened [BLOB handle] in its only argument.  The
** incremental blob I/O routines can only read or overwriting existing
** blob content; they cannot change the size of a blob.
**
** This routine only works on a [BLOB handle] which has been created
** by a prior successful call to [sqlite3_blob_open()] and which has not
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
** to this routine results in undefined and probably undesirable behavior.
**
** Requirements:
** [H17843]
*/
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);

/*
** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
**
** This function is used to read data from an open [BLOB handle] into a
** caller-supplied buffer. N bytes of data are copied into buffer Z
** from the open BLOB, starting at offset iOffset.

** to this routine results in undefined and probably undesirable behavior.
**
** See also: [sqlite3_blob_write()].
**
** Requirements:
** [H17853] [H17856] [H17859] [H17862] [H17863] [H17865] [H17868]
*/
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);

/*
** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
**
** This function is used to write data into an open [BLOB handle] from a
** caller-supplied buffer. N bytes of data are copied from the buffer Z
** into the open BLOB, starting at offset iOffset.

**
** See also: [sqlite3_blob_read()].
**
** Requirements:
** [H17873] [H17874] [H17875] [H17876] [H17877] [H17879] [H17882] [H17885]
** [H17888]
*/
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);

/*
** CAPI3REF: Virtual File System Objects {H11200} <S20100>
**
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
** that SQLite uses to interact
** with the underlying operating system.  Most SQLite builds come with a

** Unregister a VFS with the sqlite3_vfs_unregister() interface.
** If the default VFS is unregistered, another VFS is chosen as
** the default.  The choice for the new VFS is arbitrary.
**
** Requirements:
** [H11203] [H11206] [H11209] [H11212] [H11215] [H11218]
*/
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);

/*
** CAPI3REF: Mutexes {H17000} <S20000>
**
** The SQLite core uses these routines for thread
** synchronization. Though they are intended for internal
** use by SQLite, code that links against SQLite is

** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to.  {H17016} But SQLite will only request a recursive mutex in
** cases where it really needs one.  {END} If a faster non-recursive mutex
** implementation is available on the host platform, the mutex subsystem
** might return such a mutex in response to SQLITE_MUTEX_FAST.
**
** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
** a pointer to a static preexisting mutex. {END}  Six static mutexes are
** used by the current version of SQLite.  Future versions of SQLite
** may add additional static mutexes.  Static mutexes are for internal
** use by SQLite only.  Applications that use SQLite mutexes should
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
** SQLITE_MUTEX_RECURSIVE.
**
** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST

**
** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
** sqlite3_mutex_leave() is a NULL pointer, then all three routines
** behave as no-ops.
**
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
*/
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);

/*
** CAPI3REF: Mutex Methods Object {H17120} <S20130>
** EXPERIMENTAL
**
** An instance of this structure defines the low-level routines
** used to allocate and use mutexes.

** The only difference is that the public sqlite3_XXX functions enumerated
** above silently ignore any invocations that pass a NULL pointer instead
** of a valid mutex handle. The implementations of the methods defined
** by this structure are not required to handle this case, the results
** of passing a NULL pointer instead of a valid mutex handle are undefined
** (i.e. it is acceptable to provide an implementation that segfaults if
** it is passed a NULL pointer).
**
** The xMutexInit() method must be threadsafe.  It must be harmless to
** invoke xMutexInit() mutiple times within the same process and without
** intervening calls to xMutexEnd().  Second and subsequent calls to
** xMutexInit() must be no-ops.
**
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
** allocation for a static mutex.  However xMutexAlloc() may use SQLite
** memory allocation for a fast or recursive mutex.
**
** SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
** If xMutexInit fails in any way, it is expected to clean up after itself
** prior to returning.
*/
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
struct sqlite3_mutex_methods {
  int (*xMutexInit)(void);
  int (*xMutexEnd)(void);
  sqlite3_mutex *(*xMutexAlloc)(int);
  void (*xMutexFree)(sqlite3_mutex *);

** clearly the mutex cannot be held if it does not exist.  But the
** the reason the mutex does not exist is because the build is not
** using mutexes.  And we do not want the assert() containing the
** call to sqlite3_mutex_held() to fail, so a non-zero return is
** the appropriate thing to do.  {H17086} The sqlite3_mutex_notheld()
** interface should also return 1 when given a NULL pointer.
*/
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);

/*
** CAPI3REF: Mutex Types {H17001} <H17000>
**
** The [sqlite3_mutex_alloc()] interface takes a single argument
** which is one of these integer constants.
**

**
** This interface returns a pointer the [sqlite3_mutex] object that 
** serializes access to the [database connection] given in the argument
** when the [threading mode] is Serialized.
** If the [threading mode] is Single-thread or Multi-thread then this
** routine returns a NULL pointer.
*/
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);

/*
** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
**
** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
** xFileControl method for the [sqlite3_io_methods] object associated
** with a particular database identified by the second argument. {H11302} The

** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
** also return SQLITE_ERROR.  {A11309} There is no way to distinguish between
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
** xFileControl method. {END}
**
** See also: [SQLITE_FCNTL_LOCKSTATE]
*/
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);

/*
** CAPI3REF: Testing Interface {H11400} <S30800>
**
** The sqlite3_test_control() interface is used to read out internal
** state of SQLite and to inject faults into SQLite for testing
** purposes.  The first parameter is an operation code that determines
** the number, meaning, and operation of all subsequent parameters.
**
** This interface is not for use by applications.  It exists solely
** for verifying the correct operation of the SQLite library.  Depending
** on how the SQLite library is compiled, this interface might not exist.
**
** The details of the operation codes, their meanings, the parameters
** they take, and what they do are all subject to change without notice.
** Unlike most of the SQLite API, this function is not guaranteed to
** operate consistently from one release to the next.
*/
SQLITE_API int sqlite3_test_control(int op, ...);

/*
** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
**
** These constants are the valid operation code parameters used
** as the first argument to [sqlite3_test_control()].
**

** nothing is written into *pHighwater and the resetFlag is ignored.
** Other parameters record only the highwater mark and not the current
** value.  For these latter parameters nothing is written into *pCurrent.
**
** This routine returns SQLITE_OK on success and a non-zero
** [error code] on failure.
**
** This routine is threadsafe but is not atomic.  This routine can be
** called while other threads are running the same or different SQLite
** interfaces.  However the values returned in *pCurrent and
** *pHighwater reflect the status of SQLite at different points in time
** and it is possible that another thread might change the parameter
** in between the times when *pCurrent and *pHighwater are written.
**
** See also: [sqlite3_db_status()]
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);


/*
** CAPI3REF: Status Parameters {H17250} <H17200>
** EXPERIMENTAL
**
** These integer constants designate various run-time status parameters

** The current value of the requested parameter is written into *pCur
** and the highest instantaneous value is written into *pHiwtr.  If
** the resetFlg is true, then the highest instantaneous value is
** reset back down to the current value.
**
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);

/*
** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
** EXPERIMENTAL
**
** These constants are the available integer "verbs" that can be passed as
** the second argument to the [sqlite3_db_status()] interface.
**
** New verbs may be added in future releases of SQLite. Existing verbs
** might be discontinued. Applications should check the return code from
** [sqlite3_db_status()] to make sure that the call worked.
** The [sqlite3_db_status()] interface will return a non-zero error code
** if a discontinued or unsupported verb is invoked.
**
** <dl>
** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
** <dd>This parameter returns the number of lookaside memory slots currently
** checked out.</dd>
** </dl>
*/

** to be interrogated. 
** The current value of the requested counter is returned.
** If the resetFlg is true, then the counter is reset to zero after this
** interface call returns.
**
** See also: [sqlite3_status()] and [sqlite3_db_status()].
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);

/*
** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
** EXPERIMENTAL
**
** These preprocessor macros define integer codes that name counter
** values associated with the [sqlite3_stmt_status()] interface.

**
** See [sqlite3_pcache_methods] for additional information.
*/
typedef struct sqlite3_pcache sqlite3_pcache;

/*
** CAPI3REF: Application Defined Page Cache.
** KEYWORDS: {page cache}
** EXPERIMENTAL
**
** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
** register an alternative page cache implementation by passing in an 
** instance of the sqlite3_pcache_methods structure. The majority of the 
** heap memory used by SQLite is used by the page cache to cache data read 
** from, or ready to be written to, the database file. By implementing a 
** custom page cache using this API, an application can control more 
** precisely the amount of memory consumed by SQLite, the way in which 
** that memory is allocated and released, and the policies used to 
** determine exactly which parts of a database file are cached and for 
** how long.
**
** The contents of the sqlite3_pcache_methods structure are copied to an
** internal buffer by SQLite within the call to [sqlite3_config].  Hence
** the application may discard the parameter after the call to
** [sqlite3_config()] returns.
**
** The xInit() method is called once for each call to [sqlite3_initialize()]
** (usually only once during the lifetime of the process). It is passed
** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set
** up global structures and mutexes required by the custom page cache 
** implementation. 
**
** The xShutdown() method is called from within [sqlite3_shutdown()], 
** if the application invokes this API. It can be used to clean up 
** any outstanding resources before process shutdown, if required.
**
** SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
** the xInit method, so the xInit method need not be threadsafe.  The
** xShutdown method is only called from [sqlite3_shutdown()] so it does
** not need to be threadsafe either.  All other methods must be threadsafe
** in multithreaded applications.
**
** SQLite will never invoke xInit() more than once without an intervening
** call to xShutdown().
**
** The xCreate() method is used to construct a new cache instance.  SQLite
** will typically create one cache instance for each open database file,
** though this is not guaranteed. The
** first parameter, szPage, is the size in bytes of the pages that must
** be allocated by the cache.  szPage will not be a power of two.  szPage
** will the page size of the database file that is to be cached plus an
** increment (here called "R") of about 100 or 200.  SQLite will use the
** extra R bytes on each page to store metadata about the underlying
** database page on disk.  The value of R depends
** on the SQLite version, the target platform, and how SQLite was compiled.
** R is constant for a particular build of SQLite.  The second argument to
** xCreate(), bPurgeable, is true if the cache being created will
** be used to cache database pages of a file stored on disk, or
** false if it is used for an in-memory database. The cache implementation
** does not have to do anything special based with the value of bPurgeable;
** it is purely advisory.  On a cache where bPurgeable is false, SQLite will
** never invoke xUnpin() except to deliberately delete a page.
** In other words, a cache created with bPurgeable set to false will
** never contain any unpinned pages.
**
** The xCachesize() method may be called at any time by SQLite to set the
** suggested maximum cache-size (number of pages stored by) the cache
** instance passed as the first argument. This is the value configured using
** the SQLite "[PRAGMA cache_size]" command. As with the bPurgeable parameter,
** the implementation is not required to do anything with this
** value; it is advisory only.
**
** The xPagecount() method should return the number of pages currently
** stored in the cache.
** 
** The xFetch() method is used to fetch a page and return a pointer to it. 
** A 'page', in this context, is a buffer of szPage bytes aligned at an
** 8-byte boundary. The page to be fetched is determined by the key. The
** mimimum key value is 1. After it has been retrieved using xFetch, the page 
** is considered to be "pinned".
**
** If the requested page is already in the page cache, then the page cache
** implementation must return a pointer to the page buffer with its content
** intact.  If the requested page is not already in the cache, then the
** behavior of the cache implementation is determined by the value of the
** createFlag parameter passed to xFetch, according to the following table:
**
** <table border=1 width=85% align=center>
** <tr><th> createFlag <th> Behaviour when page is not already in cache

** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.






** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.

**                 Otherwise return NULL.



** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return




**                 NULL if allocating a new page is effectively impossible.
** </table>
**
** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
** attempt to unpin one or more cache pages by spilling the content of
** pinned pages to disk and synching the operating system disk cache. After
** attempting to unpin pages, the xFetch() method will be invoked again with
** a createFlag of 2.
**
** xUnpin() is called by SQLite with a pointer to a currently pinned page
** as its second argument. If the third parameter, discard, is non-zero,
** then the page should be evicted from the cache. In this case SQLite 
** assumes that the next time the page is retrieved from the cache using
** the xFetch() method, it will be zeroed. If the discard parameter is
** zero, then the page is considered to be unpinned. The cache implementation
** may choose to evict unpinned pages at any time.



**
** The cache is not required to perform any reference counting. A single 
** call to xUnpin() unpins the page regardless of the number of prior calls 
** to xFetch().
**
** The xRekey() method is used to change the key value associated with the
** page passed as the second argument from oldKey to newKey. If the cache

** The [sqlite3_backup] object itself is partially threadsafe. Multiple 
** threads may safely make multiple concurrent calls to sqlite3_backup_step().
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
** APIs are not strictly speaking threadsafe. If they are invoked at the
** same time as another thread is invoking sqlite3_backup_step() it is
** possible that they return invalid values.
*/
SQLITE_API sqlite3_backup *sqlite3_backup_init(
  sqlite3 *pDest,                        /* Destination database handle */
  const char *zDestName,                 /* Destination database name */
  sqlite3 *pSource,                      /* Source database handle */
  const char *zSourceName                /* Source database name */
);
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);

/*
** CAPI3REF: Unlock Notification
** EXPERIMENTAL
**
** When running in shared-cache mode, a database operation may fail with
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or

**
** One way around this problem is to check the extended error code returned
** by an sqlite3_step() call. If there is a blocking connection, then the
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
** the special "DROP TABLE/INDEX" case, the extended error code is just 
** SQLITE_LOCKED.
*/
SQLITE_API int sqlite3_unlock_notify(
  sqlite3 *pBlocked,                          /* Waiting connection */
  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
  void *pNotifyArg                            /* Argument to pass to xNotify */
);


/*
** CAPI3REF: String Comparison
** EXPERIMENTAL
**
** The [sqlite3_strnicmp()] API allows applications and extensions to
** compare the contents of two buffers containing UTF-8 strings in a
** case-indendent fashion, using the same definition of case independence 
** that SQLite uses internally when comparing identifiers.
*/
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);

/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# undef double
#endif

#if 0
}  /* End of the 'extern "C"' block */
#endif
#endif




/************** End of sqlite3.h *********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include hash.h in the middle of sqliteInt.h ******************/
/************** Begin file hash.h ********************************************/
/*

** If compiling for a processor that lacks floating point support,
** substitute integer for floating-point
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# define double sqlite_int64
# define LONGDOUBLE_TYPE sqlite_int64
# ifndef SQLITE_BIG_DBL
#   define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
# endif
# define SQLITE_OMIT_DATETIME_FUNCS 1
# define SQLITE_OMIT_TRACE 1
# undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
# undef SQLITE_HAVE_ISNAN
#endif
#ifndef SQLITE_BIG_DBL

** the default file format for new databases and the maximum file format
** that the library can read.
*/
#define SQLITE_MAX_FILE_FORMAT 4
#ifndef SQLITE_DEFAULT_FILE_FORMAT
# define SQLITE_DEFAULT_FILE_FORMAT 1
#endif

#ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
# define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
#endif

/*
** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
** on the command-line
*/
#ifndef SQLITE_TEMP_STORE
# define SQLITE_TEMP_STORE 1

typedef struct ExprList ExprList;
typedef struct ExprSpan ExprSpan;
typedef struct FKey FKey;
typedef struct FuncDef FuncDef;
typedef struct FuncDefHash FuncDefHash;
typedef struct IdList IdList;
typedef struct Index Index;
typedef struct IndexSample IndexSample;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
typedef struct Savepoint Savepoint;
typedef struct Select Select;
typedef struct SrcList SrcList;
typedef struct StrAccum StrAccum;
typedef struct Table Table;
typedef struct TableLock TableLock;
typedef struct Token Token;
typedef struct TriggerPrg TriggerPrg;
typedef struct TriggerStep TriggerStep;
typedef struct Trigger Trigger;
typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct Walker Walker;
typedef struct WherePlan WherePlan;
typedef struct WhereInfo WhereInfo;

/*
** The names of the following types declared in vdbeInt.h are required
** for the VdbeOp definition.
*/
typedef struct VdbeFunc VdbeFunc;
typedef struct Mem Mem;
typedef struct SubProgram SubProgram;

/*
** A single instruction of the virtual machine has an opcode
** and as many as three operands.  The instruction is recorded
** as an instance of the following structure:
*/
struct VdbeOp {
  u8 opcode;          /* What operation to perform */
  signed char p4type; /* One of the P4_xxx constants for p4 */
  u8 opflags;         /* Not currently used */
  u8 p5;              /* Fifth parameter is an unsigned character */
  int p1;             /* First operand */
  int p2;             /* Second parameter (often the jump destination) */
  int p3;             /* The third parameter */
  union {             /* fourth parameter */
    int i;                 /* Integer value if p4type==P4_INT32 */
    void *p;               /* Generic pointer */
    char *z;               /* Pointer to data for string (char array) types */
    i64 *pI64;             /* Used when p4type is P4_INT64 */
    double *pReal;         /* Used when p4type is P4_REAL */
    FuncDef *pFunc;        /* Used when p4type is P4_FUNCDEF */
    VdbeFunc *pVdbeFunc;   /* Used when p4type is P4_VDBEFUNC */
    CollSeq *pColl;        /* Used when p4type is P4_COLLSEQ */
    Mem *pMem;             /* Used when p4type is P4_MEM */
    VTable *pVtab;         /* Used when p4type is P4_VTAB */
    KeyInfo *pKeyInfo;     /* Used when p4type is P4_KEYINFO */
    int *ai;               /* Used when p4type is P4_INTARRAY */
    SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
  } p4;
#ifdef SQLITE_DEBUG
  char *zComment;          /* Comment to improve readability */
#endif
#ifdef VDBE_PROFILE
  int cnt;                 /* Number of times this instruction was executed */
  u64 cycles;              /* Total time spent executing this instruction */
#endif
};
typedef struct VdbeOp VdbeOp;


/*
** A sub-routine used to implement a trigger program.
*/
struct SubProgram {
  VdbeOp *aOp;                  /* Array of opcodes for sub-program */
  int nOp;                      /* Elements in aOp[] */
  int nMem;                     /* Number of memory cells required */
  int nCsr;                     /* Number of cursors required */
  int nRef;                     /* Number of pointers to this structure */
  void *token;                  /* id that may be used to recursive triggers */
};

/*
** A smaller version of VdbeOp used for the VdbeAddOpList() function because
** it takes up less space.
*/
struct VdbeOpList {
  u8 opcode;          /* What operation to perform */
  signed char p1;     /* First operand */
  signed char p2;     /* Second parameter (often the jump destination) */
  signed char p3;     /* Third parameter */
};
typedef struct VdbeOpList VdbeOpList;

/*
** Allowed values of VdbeOp.p4type
*/
#define P4_NOTUSED    0   /* The P4 parameter is not used */
#define P4_DYNAMIC  (-1)  /* Pointer to a string obtained from sqliteMalloc() */
#define P4_STATIC   (-2)  /* Pointer to a static string */
#define P4_COLLSEQ  (-4)  /* P4 is a pointer to a CollSeq structure */
#define P4_FUNCDEF  (-5)  /* P4 is a pointer to a FuncDef structure */
#define P4_KEYINFO  (-6)  /* P4 is a pointer to a KeyInfo structure */
#define P4_VDBEFUNC (-7)  /* P4 is a pointer to a VdbeFunc structure */
#define P4_MEM      (-8)  /* P4 is a pointer to a Mem*    structure */
#define P4_TRANSIENT (-9) /* P4 is a pointer to a transient string */
#define P4_VTAB     (-10) /* P4 is a pointer to an sqlite3_vtab structure */
#define P4_MPRINTF  (-11) /* P4 is a string obtained from sqlite3_mprintf() */
#define P4_REAL     (-12) /* P4 is a 64-bit floating point value */
#define P4_INT64    (-13) /* P4 is a 64-bit signed integer */
#define P4_INT32    (-14) /* P4 is a 32-bit signed integer */
#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
#define P4_SUBPROGRAM  (-18) /* P4 is a pointer to a SubProgram structure */

/* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
** is made.  That copy is freed when the Vdbe is finalized.  But if the
** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used.  It still
** gets freed when the Vdbe is finalized so it still should be obtained
** from a single sqliteMalloc().  But no copy is made and the calling
** function should *not* try to free the KeyInfo.

#define OP_Copy                                20
#define OP_Trace                               21
#define OP_Function                            22
#define OP_IfNeg                               23
#define OP_And                                 67   /* same as TK_AND      */
#define OP_Subtract                            85   /* same as TK_MINUS    */
#define OP_Noop                                24
#define OP_Program                             25
#define OP_Return                              26
#define OP_Remainder                           88   /* same as TK_REM      */
#define OP_NewRowid                            27
#define OP_Multiply                            86   /* same as TK_STAR     */
#define OP_Variable                            28
#define OP_String                              29
#define OP_RealAffinity                        30
#define OP_VRename                             31
#define OP_ParseSchema                         32
#define OP_VOpen                               33
#define OP_Close                               34
#define OP_CreateIndex                         35
#define OP_IsUnique                            36
#define OP_NotFound                            37
#define OP_Int64                               38
#define OP_MustBeInt                           39
#define OP_Halt                                40
#define OP_Rowid                               41
#define OP_IdxLT                               42
#define OP_AddImm                              43

#define OP_RowData                             44
#define OP_MemMax                              45
#define OP_Or                                  66   /* same as TK_OR       */
#define OP_NotExists                           46
#define OP_Gosub                               47
#define OP_Divide                              87   /* same as TK_SLASH    */
#define OP_Integer                             48

#define OP_Last                                54
#define OP_SeekLe                              55
#define OP_IsNull                              71   /* same as TK_ISNULL   */
#define OP_IncrVacuum                          56
#define OP_IdxRowid                            57
#define OP_ShiftRight                          83   /* same as TK_RSHIFT   */
#define OP_ResetCount                          58

#define OP_Yield                               59
#define OP_DropTrigger                         60
#define OP_DropIndex                           61
#define OP_Param                               62
#define OP_IdxGE                               63
#define OP_IdxDelete                           64
#define OP_Vacuum                              65
#define OP_IfNot                               68
#define OP_DropTable                           69
#define OP_SeekLt                              70
#define OP_MakeRecord                          79

#define OP_Clear                               98
#define OP_Le                                  76   /* same as TK_LE       */
#define OP_VerifyCookie                        99
#define OP_AggStep                            100
#define OP_ToText                             141   /* same as TK_TO_TEXT  */
#define OP_Not                                 19   /* same as TK_NOT      */
#define OP_ToReal                             145   /* same as TK_TO_REAL  */

#define OP_Transaction                        101
#define OP_VFilter                            102
#define OP_Ne                                  73   /* same as TK_NE       */
#define OP_VDestroy                           103

#define OP_BitOr                               81   /* same as TK_BITOR    */
#define OP_Next                               104
#define OP_Count                              105
#define OP_IdxInsert                          106
#define OP_Lt                                  77   /* same as TK_LT       */
#define OP_SeekGe                             107
#define OP_Insert                             108
#define OP_Destroy                            109
#define OP_ReadCookie                         110
#define OP_RowSetTest                         111
#define OP_LoadAnalysis                       112
#define OP_Explain                            113
#define OP_HaltIfNull                         114
#define OP_OpenPseudo                         115
#define OP_OpenEphemeral                      116
#define OP_Null                               117
#define OP_Move                               118
#define OP_Blob                               119
#define OP_Add                                 84   /* same as TK_PLUS     */
#define OP_Rewind                             120
#define OP_SeekGt                             121
#define OP_VBegin                             122
#define OP_VUpdate                            123
#define OP_IfZero                             124
#define OP_BitNot                              93   /* same as TK_BITNOT   */
#define OP_VCreate                            125
#define OP_Found                              126
#define OP_IfPos                              127
#define OP_NullRow                            128
#define OP_Jump                               129
#define OP_Permutation                        131

/* The following opcode values are never used */
#define OP_NotUsed_132                        132
#define OP_NotUsed_133                        133
#define OP_NotUsed_134                        134
#define OP_NotUsed_135                        135
#define OP_NotUsed_136                        136
#define OP_NotUsed_137                        137
#define OP_NotUsed_138                        138
#define OP_NotUsed_139                        139
#define OP_NotUsed_140                        140

#define OPFLG_IN2             0x0008  /* in2:   P2 is an input */
#define OPFLG_IN3             0x0010  /* in3:   P3 is an input */
#define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */
#define OPFLG_INITIALIZER {\
/*   0 */ 0x00, 0x01, 0x00, 0x00, 0x10, 0x08, 0x02, 0x00,\
/*   8 */ 0x00, 0x04, 0x00, 0x05, 0x00, 0x00, 0x00, 0x00,\
/*  16 */ 0x02, 0x00, 0x01, 0x04, 0x04, 0x00, 0x00, 0x05,\
/*  24 */ 0x00, 0x01, 0x04, 0x02, 0x00, 0x02, 0x04, 0x00,\
/*  32 */ 0x00, 0x00, 0x00, 0x02, 0x11, 0x11, 0x02, 0x05,\
/*  40 */ 0x00, 0x02, 0x11, 0x04, 0x00, 0x08, 0x11, 0x01,\
/*  48 */ 0x02, 0x01, 0x21, 0x08, 0x00, 0x02, 0x01, 0x11,\
/*  56 */ 0x01, 0x02, 0x00, 0x04, 0x00, 0x00, 0x02, 0x11,\
/*  64 */ 0x00, 0x00, 0x2c, 0x2c, 0x05, 0x00, 0x11, 0x05,\
/*  72 */ 0x05, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x00,\
/*  80 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c,\
/*  88 */ 0x2c, 0x2c, 0x00, 0x00, 0x00, 0x04, 0x02, 0x00,\
/*  96 */ 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00,\
/* 104 */ 0x01, 0x02, 0x08, 0x11, 0x00, 0x02, 0x02, 0x15,\
/* 112 */ 0x00, 0x00, 0x10, 0x00, 0x00, 0x02, 0x00, 0x02,\
/* 120 */ 0x01, 0x11, 0x00, 0x00, 0x05, 0x00, 0x11, 0x05,\
/* 128 */ 0x00, 0x01, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 136 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x04, 0x04,\
/* 144 */ 0x04, 0x04,}

/************** End of opcodes.h *********************************************/
/************** Continuing where we left off in vdbe.h ***********************/

/*

SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe*, int addr, int N);
SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe*);
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE   int sqlite3VdbeMayAbort(Vdbe*);
SQLITE_PRIVATE   void sqlite3VdbeTrace(Vdbe*,FILE*);
#endif
SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe*);
SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe*,int);
SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe*);
SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *, SubProgram *, int);

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
SQLITE_PRIVATE int sqlite3VdbeReleaseMemory(int);
#endif
SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,char*,int);
SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);

**
*/
#define PENDING_BYTE      sqlite3PendingByte
#define RESERVED_BYTE     (PENDING_BYTE+1)
#define SHARED_FIRST      (PENDING_BYTE+2)
#define SHARED_SIZE       510

/*
** Wrapper around OS specific sqlite3_os_init() function.
*/
SQLITE_PRIVATE int sqlite3OsInit(void);

/* 
** Functions for accessing sqlite3_file methods 
*/
SQLITE_PRIVATE int sqlite3OsClose(sqlite3_file*);
SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);

#define DB_UnresetViews    0x0002  /* Some views have defined column names */
#define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */

/*
** The number of different kinds of things that can be limited
** using the sqlite3_limit() interface.
*/
#define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)

/*
** Lookaside malloc is a set of fixed-size buffers that can be used
** to satisfy small transient memory allocation requests for objects
** associated with a particular database connection.  The use of
** lookaside malloc provides a significant performance enhancement
** (approx 10%) by avoiding numerous malloc/free requests while parsing

#define SQLITE_ReadUncommitted 0x00004000 /* For shared-cache mode */
#define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
#define SQLITE_FullFSync      0x00010000  /* Use full fsync on the backend */
#define SQLITE_LoadExtension  0x00020000  /* Enable load_extension */

#define SQLITE_RecoveryMode   0x00040000  /* Ignore schema errors */
#define SQLITE_ReverseOrder   0x00100000  /* Reverse unordered SELECTs */
#define SQLITE_RecTriggers    0x00200000  /* Enable recursive triggers */

/*
** Possible values for the sqlite.magic field.
** The numbers are obtained at random and have no special meaning, other
** than being distinct from one another.
*/
#define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */

  u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
  char *zColAff;   /* String defining the affinity of each column */
  Index *pNext;    /* The next index associated with the same table */
  Schema *pSchema; /* Schema containing this index */
  u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
  char **azColl;   /* Array of collation sequence names for index */
  IndexSample *aSample;    /* Array of SQLITE_INDEX_SAMPLES samples */
};

/*
** Each sample stored in the sqlite_stat2 table is represented in memory 
** using a structure of this type.
*/
struct IndexSample {
  union {
    char *z;        /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
    double r;       /* Value if eType is SQLITE_FLOAT or SQLITE_INTEGER */
  } u;
  u8 eType;         /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
  u8 nByte;         /* Size in byte of text or blob. */
};

/*
** Each token coming out of the lexer is an instance of
** this structure.  Tokens are also used as part of an expression.
**
** Note if Token.z==0 then Token.dyn and Token.n are undefined and

  /* If the EP_Reduced flag is set in the Expr.flags mask, then no
  ** space is allocated for the fields below this point. An attempt to
  ** access them will result in a segfault or malfunction.
  *********************************************************************/

  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old */
  i16 iColumn;           /* TK_COLUMN: column index.  -1 for rowid */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
  u8 flags2;             /* Second set of flags.  EP2_... */
  u8 op2;                /* If a TK_REGISTER, the original value of Expr.op */
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  Table *pTab;           /* Table for TK_COLUMN expressions. */
#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
};

/*
** Size of the column cache
*/
#ifndef SQLITE_N_COLCACHE
# define SQLITE_N_COLCACHE 10
#endif

/*
** At least one instance of the following structure is created for each 
** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
** statement. All such objects are stored in the linked list headed at
** Parse.pTriggerPrg and deleted once statement compilation has been
** completed.
**
** A Vdbe sub-program that implements the body and WHEN clause of trigger
** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
** The Parse.pTriggerPrg list never contains two entries with the same
** values for both pTrigger and orconf.
**
** The TriggerPrg.oldmask variable is set to a mask of old.* columns
** accessed (or set to 0 for triggers fired as a result of INSERT 
** statements).
*/
struct TriggerPrg {
  Trigger *pTrigger;      /* Trigger this program was coded from */
  int orconf;             /* Default ON CONFLICT policy */
  SubProgram *pProgram;   /* Program implementing pTrigger/orconf */
  u32 oldmask;            /* Mask of old.* columns accessed */
  TriggerPrg *pNext;      /* Next entry in Parse.pTriggerPrg list */
};

/*
** An SQL parser context.  A copy of this structure is passed through
** the parser and down into all the parser action routine in order to
** carry around information that is global to the entire parse.
**
** The structure is divided into two parts.  When the parser and code
** generate call themselves recursively, the first part of the structure

    u8 tempReg;           /* iReg is a temp register that needs to be freed */
    int iLevel;           /* Nesting level */
    int iReg;             /* Reg with value of this column. 0 means none. */
    int lru;              /* Least recently used entry has the smallest value */
  } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
  u32 writeMask;       /* Start a write transaction on these databases */
  u32 cookieMask;      /* Bitmask of schema verified databases */
  u8 isMultiWrite;     /* True if statement may affect/insert multiple rows */
  u8 mayAbort;         /* True if statement may throw an ABORT exception */
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
  int nMaxArg;         /* Max args passed to user function by sub-program */

  /* Information used while coding trigger programs. */
  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
  Table *pTriggerTab;  /* Table triggers are being coded for */
  u32 oldmask;         /* Mask of old.* columns referenced */
  u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
  u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */

  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;            /* Number of '?' variables seen in the SQL so far */
  int nVarExpr;        /* Number of used slots in apVarExpr[] */
  int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
  Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
  int nAlias;          /* Number of aliased result set columns */
  int nAliasAlloc;     /* Number of allocated slots for aAlias[] */
  int *aAlias;         /* Register used to hold aliased result */
  u8 explain;          /* True if the EXPLAIN flag is found on the query */
  Token sNameToken;    /* Token with unqualified schema object name */
  Token sLastToken;    /* The last token parsed */
  const char *zTail;   /* All SQL text past the last semicolon parsed */
  Table *pNewTable;    /* A table being constructed by CREATE TABLE */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */

  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;                /* Complete text of a module argument */
  u8 declareVtab;            /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;             /* Number of virtual tables to lock */
  Table **apVtabLock;        /* Pointer to virtual tables needing locking */
#endif
  int nHeight;            /* Expression tree height of current sub-select */
  Table *pZombieTab;      /* List of Table objects to delete after code gen */
  TriggerPrg *pTriggerPrg;    /* Linked list of coded triggers */
};

#ifdef SQLITE_OMIT_VIRTUALTABLE
  #define IN_DECLARE_VTAB 0
#else
  #define IN_DECLARE_VTAB (pParse->declareVtab)
#endif

/*
** An instance of the following structure can be declared on a stack and used
** to save the Parse.zAuthContext value so that it can be restored later.
*/
struct AuthContext {
  const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
  Parse *pParse;              /* The Parse structure */
};

/*
** Bitfield flags for P5 value in OP_Insert and OP_Delete
*/
#define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */

/*
 * Each trigger present in the database schema is stored as an instance of
 * struct Trigger. 
 *
 * Pointers to instances of struct Trigger are stored in two ways.
 * 1. In the "trigHash" hash table (part of the sqlite3* that represents the 
 *    database). This allows Trigger structures to be retrieved by name.
 * 2. All triggers associated with a single table form a linked list, using the
 *    pNext member of struct Trigger. A pointer to the first element of the
 *    linked list is stored as the "pTrigger" member of the associated
 *    struct Table.
 *
 * The "step_list" member points to the first element of a linked list
 * containing the SQL statements specified as the trigger program.
 */
struct Trigger {
  char *zName;            /* The name of the trigger                        */
  char *table;            /* The table or view to which the trigger applies */
  u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
  u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
  Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
  IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
                             the <column-list> is stored here */
  Schema *pSchema;        /* Schema containing the trigger */

  Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
  ExprList *pExprList; /* SET clause for UPDATE.  VALUES clause for INSERT */
  IdList *pIdList;     /* Column names for INSERT */
  TriggerStep *pNext;  /* Next in the link-list */
  TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
};








































/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references
** explicit.  
*/
typedef struct DbFixer DbFixer;
struct DbFixer {

  int nPage;                        /* Number of pages in pPage[] */
  int mxParserStack;                /* maximum depth of the parser stack */
  int sharedCacheEnabled;           /* true if shared-cache mode enabled */
  /* The above might be initialized to non-zero.  The following need to always
  ** initially be zero, however. */
  int isInit;                       /* True after initialization has finished */
  int inProgress;                   /* True while initialization in progress */
  int isMutexInit;                  /* True after mutexes are initialized */
  int isMallocInit;                 /* True after malloc is initialized */
  int isPCacheInit;                 /* True after malloc is initialized */
  sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
  int nRefInitMutex;                /* Number of users of pInitMutex */
};

/*
** Context pointer passed down through the tree-walk.
*/

SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
SQLITE_PRIVATE int sqlite3IsRowid(const char*);
SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int, Trigger *, int);
SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
                                     int*,int,int,int,int,int*);
SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*, int, int, int);
SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
SQLITE_PRIVATE void sqlite3MayAbort(Parse *);
SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, char*, int);
SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3*,IdList*);
SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3*,Select*,int);
SQLITE_PRIVATE void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
SQLITE_PRIVATE FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);

SQLITE_PRIVATE   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
                           Expr*,int, int);
SQLITE_PRIVATE   void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
SQLITE_PRIVATE   void sqlite3DropTrigger(Parse*, SrcList*, int);
SQLITE_PRIVATE   void sqlite3DropTriggerPtr(Parse*, Trigger*);
SQLITE_PRIVATE   Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
SQLITE_PRIVATE   Trigger *sqlite3TriggerList(Parse *, Table *);
SQLITE_PRIVATE   void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
                            int, int, int, int);
  void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
SQLITE_PRIVATE   void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
SQLITE_PRIVATE   TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
SQLITE_PRIVATE   TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
                                        ExprList*,Select*,u8);
SQLITE_PRIVATE   TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
SQLITE_PRIVATE   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
SQLITE_PRIVATE   void sqlite3DeleteTrigger(sqlite3*, Trigger*);
SQLITE_PRIVATE   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
SQLITE_PRIVATE   u32 sqlite3TriggerOldmask(Parse*,Trigger*,int,ExprList*,Table*,int);
# define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
#else
# define sqlite3TriggersExist(B,C,D,E,F) 0
# define sqlite3DeleteTrigger(A,B)
# define sqlite3DropTriggerPtr(A,B)
# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J)
# define sqlite3TriggerList(X, Y) 0
# define sqlite3ParseToplevel(p) p
# define sqlite3TriggerOldmask(A,B,C,D,E,F) 0
#endif

SQLITE_PRIVATE int sqlite3JoinType(Parse*, Token*, Token*, Token*);
SQLITE_PRIVATE void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse*, int);
#ifndef SQLITE_OMIT_AUTHORIZATION
SQLITE_PRIVATE   void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);

*/
#define getVarint32(A,B)  (u8)((*(A)<(u8)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), (u32 *)&(B)))
#define putVarint32(A,B)  (u8)(((u32)(B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
SQLITE_PRIVATE void sqlite3TableAffinityStr(Vdbe *, Table *);
SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2);
SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr);
SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*);
SQLITE_PRIVATE void sqlite3Error(sqlite3*, int, const char*,...);
SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);

SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value*, u8);
SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value*, u8);
SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8, 
                        void(*)(void*));
SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int);
#ifdef SQLITE_ENABLE_STAT2
SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
#endif
SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
#ifndef SQLITE_AMALGAMATION
SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;

SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(sqlite3*, u8, CollSeq *, const char*);
SQLITE_PRIVATE char sqlite3AffinityType(const char*);
SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index*);
SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse*, int, int);
SQLITE_PRIVATE void sqlite3SchemaFree(void *);
SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *);

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains definitions of global variables and contants.


*/


/* An array to map all upper-case characters into their corresponding
** lower-case character. 
**
** SQLite only considers US-ASCII (or EBCDIC) characters.  We do not

   0,                         /* szScratch */
   0,                         /* nScratch */
   (void*)0,                  /* pPage */
   0,                         /* szPage */
   0,                         /* nPage */
   0,                         /* mxParserStack */
   0,                         /* sharedCacheEnabled */
   /* All the rest should always be initialized to zero */
   0,                         /* isInit */
   0,                         /* inProgress */
   0,                         /* isMutexInit */
   0,                         /* isMallocInit */
   0,                         /* isPCacheInit */
   0,                         /* pInitMutex */
   0,                         /* nRefInitMutex */
};


/*
** Hash table for global functions - functions common to all

  const char *zPath, 
  sqlite3_file *pFile, 
  int flags, 
  int *pFlagsOut
){
  int rc;
  DO_OS_MALLOC_TEST(0);
  /* 0x7f1f is a mask of SQLITE_OPEN_ flags that are valid to be passed
  ** down into the VFS layer.  Some SQLITE_OPEN_ flags (for example,
  ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
  ** reaching the VFS. */
  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x7f1f, pFlagsOut);
  assert( rc==SQLITE_OK || pFile->pMethods==0 );
  return rc;
}
SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  return pVfs->xDelete(pVfs, zPath, dirSync);
}
SQLITE_PRIVATE int sqlite3OsAccess(

SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *pFile){
  int rc = SQLITE_OK;
  assert( pFile );
  rc = sqlite3OsClose(pFile);
  sqlite3_free(pFile);
  return rc;
}

/*
** This function is a wrapper around the OS specific implementation of
** sqlite3_os_init(). The purpose of the wrapper is to provide the
** ability to simulate a malloc failure, so that the handling of an
** error in sqlite3_os_init() by the upper layers can be tested.
*/
SQLITE_PRIVATE int sqlite3OsInit(void){
  void *p = sqlite3_malloc(10);
  if( p==0 ) return SQLITE_NOMEM;
  sqlite3_free(p);
  return sqlite3_os_init();
}

/*
** The list of all registered VFS implementations.
*/
static sqlite3_vfs * SQLITE_WSD vfsList = 0;
#define vfsList GLOBAL(sqlite3_vfs *, vfsList)

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite. 
**
** This version of the memory allocation subsystem omits all
** use of malloc(). The application gives SQLite a block of memory
** before calling sqlite3_initialize() from which allocations
** are made and returned by the xMalloc() and xRealloc() 
** implementations. Once sqlite3_initialize() has been called,
** the amount of memory available to SQLite is fixed and cannot
** be changed.
**
** This version of the memory allocation subsystem is included
** in the build only if SQLITE_ENABLE_MEMSYS5 is defined.
**
** This memory allocator uses the following algorithm:
**
**   1.  All memory allocations sizes are rounded up to a power of 2.
**
**   2.  If two adjacent free blocks are the halves of a larger block,
**       then the two blocks are coalesed into the single larger block.
**
**   3.  New memory is allocated from the first available free block.
**
** This algorithm is described in: J. M. Robson. "Bounds for Some Functions
** Concerning Dynamic Storage Allocation". Journal of the Association for
** Computing Machinery, Volume 21, Number 8, July 1974, pages 491-499.
** 
** Let n be the size of the largest allocation divided by the minimum
** allocation size (after rounding all sizes up to a power of 2.)  Let M
** be the maximum amount of memory ever outstanding at one time.  Let
** N be the total amount of memory available for allocation.  Robson
** proved that this memory allocator will never breakdown due to 
** fragmentation as long as the following constraint holds:
**
**      N >=  M*(1 + log2(n)/2) - n + 1
**
** The sqlite3_status() logic tracks the maximum values of n and M so
** that an application can, at any time, verify this constraint.
*/

/*
** This version of the memory allocator is used only when 
** SQLITE_ENABLE_MEMSYS5 is defined.
*/
#ifdef SQLITE_ENABLE_MEMSYS5

/*
** A minimum allocation is an instance of the following structure.
** Larger allocations are an array of these structures where the
** size of the array is a power of 2.
**
** The size of this object must be a power of two.  That fact is
** verified in memsys5Init().
*/
typedef struct Mem5Link Mem5Link;
struct Mem5Link {
  int next;       /* Index of next free chunk */
  int prev;       /* Index of previous free chunk */
};

/*
** Maximum size of any allocation is ((1<<LOGMAX)*mem5.szAtom). Since
** mem5.szAtom is always at least 8 and 32-bit integers are used,
** it is not actually possible to reach this limit.
*/
#define LOGMAX 30

/*
** Masks used for mem5.aCtrl[] elements.
*/
#define CTRL_LOGSIZE  0x1f    /* Log2 Size of this block */
#define CTRL_FREE     0x20    /* True if not checked out */

/*
** All of the static variables used by this module are collected
** into a single structure named "mem5".  This is to keep the
** static variables organized and to reduce namespace pollution
** when this module is combined with other in the amalgamation.
*/
static SQLITE_WSD struct Mem5Global {
  /*
  ** Memory available for allocation
  */
  int szAtom;      /* Smallest possible allocation in bytes */
  int nBlock;      /* Number of szAtom sized blocks in zPool */
  u8 *zPool;       /* Memory available to be allocated */
  
  /*
  ** Mutex to control access to the memory allocation subsystem.
  */
  sqlite3_mutex *mutex;

  /*
  ** Performance statistics
  */
  u64 nAlloc;         /* Total number of calls to malloc */
  u64 totalAlloc;     /* Total of all malloc calls - includes internal frag */
  u64 totalExcess;    /* Total internal fragmentation */
  u32 currentOut;     /* Current checkout, including internal fragmentation */
  u32 currentCount;   /* Current number of distinct checkouts */
  u32 maxOut;         /* Maximum instantaneous currentOut */
  u32 maxCount;       /* Maximum instantaneous currentCount */
  u32 maxRequest;     /* Largest allocation (exclusive of internal frag) */
  
  /*
  ** Lists of free blocks.  aiFreelist[0] is a list of free blocks of
  ** size mem5.szAtom.  aiFreelist[1] holds blocks of size szAtom*2.
  ** and so forth.
  */
  int aiFreelist[LOGMAX+1];

  /*
  ** Space for tracking which blocks are checked out and the size
  ** of each block.  One byte per block.
  */
  u8 *aCtrl;

} mem5 = { 0 };

/*
** Access the static variable through a macro for SQLITE_OMIT_WSD
*/
#define mem5 GLOBAL(struct Mem5Global, mem5)

/*
** Assuming mem5.zPool is divided up into an array of Mem5Link
** structures, return a pointer to the idx-th such lik.
*/
#define MEM5LINK(idx) ((Mem5Link *)(&mem5.zPool[(idx)*mem5.szAtom]))

/*
** Unlink the chunk at mem5.aPool[i] from list it is currently
** on.  It should be found on mem5.aiFreelist[iLogsize].
*/
static void memsys5Unlink(int i, int iLogsize){
  int next, prev;

/*
** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
** will already be held (obtained by code in malloc.c) if
** sqlite3GlobalConfig.bMemStat is true.
*/
static void memsys5Enter(void){



  sqlite3_mutex_enter(mem5.mutex);
}
static void memsys5Leave(void){
  sqlite3_mutex_leave(mem5.mutex);
}

/*
** Return the size of an outstanding allocation, in bytes.  The
** size returned omits the 8-byte header overhead.  This only
** works for chunks that are currently checked out.
*/
static int memsys5Size(void *p){
  int iSize = 0;
  if( p ){
    int i = ((u8 *)p-mem5.zPool)/mem5.szAtom;
    assert( i>=0 && i<mem5.nBlock );
    iSize = mem5.szAtom * (1 << (mem5.aCtrl[i]&CTRL_LOGSIZE));
  }
  return iSize;
}

/*
** Find the first entry on the freelist iLogsize.  Unlink that
** entry and return its index. 

  }
  memsys5Unlink(iFirst, iLogsize);
  return iFirst;
}

/*
** Return a block of memory of at least nBytes in size.
** Return NULL if unable.  Return NULL if nBytes==0.
**
** The caller guarantees that nByte positive.
**
** The caller has obtained a mutex prior to invoking this
** routine so there is never any chance that two or more
** threads can be in this routine at the same time.
*/
static void *memsys5MallocUnsafe(int nByte){
  int i;           /* Index of a mem5.aPool[] slot */
  int iBin;        /* Index into mem5.aiFreelist[] */
  int iFullSz;     /* Size of allocation rounded up to power of 2 */
  int iLogsize;    /* Log2 of iFullSz/POW2_MIN */

  /* nByte must be a positive */
  assert( nByte>0 );

  /* Keep track of the maximum allocation request.  Even unfulfilled
  ** requests are counted */
  if( (u32)nByte>mem5.maxRequest ){
    mem5.maxRequest = nByte;
  }

  /* Abort if the requested allocation size is larger than the largest
  ** power of two that we can represent using 32-bit signed integers.
  */
  if( nByte > 0x40000000 ){
    return 0;
  }

  /* Round nByte up to the next valid power of two */
  for(iFullSz=mem5.szAtom, iLogsize=0; iFullSz<nByte; iFullSz *= 2, iLogsize++){}

  /* Make sure mem5.aiFreelist[iLogsize] contains at least one free
  ** block.  If not, then split a block of the next larger power of
  ** two in order to create a new free block of size iLogsize.
  */
  for(iBin=iLogsize; mem5.aiFreelist[iBin]<0 && iBin<=LOGMAX; iBin++){}
  if( iBin>LOGMAX ) return 0;

  mem5.totalExcess += iFullSz - nByte;
  mem5.currentCount++;
  mem5.currentOut += iFullSz;
  if( mem5.maxCount<mem5.currentCount ) mem5.maxCount = mem5.currentCount;
  if( mem5.maxOut<mem5.currentOut ) mem5.maxOut = mem5.currentOut;

  /* Return a pointer to the allocated memory. */
  return (void*)&mem5.zPool[i*mem5.szAtom];
}

/*
** Free an outstanding memory allocation.
*/
static void memsys5FreeUnsafe(void *pOld){
  u32 size, iLogsize;
  int iBlock;

  /* Set iBlock to the index of the block pointed to by pOld in 
  ** the array of mem5.szAtom byte blocks pointed to by mem5.zPool.
  */
  iBlock = ((u8 *)pOld-mem5.zPool)/mem5.szAtom;

  /* Check that the pointer pOld points to a valid, non-free block. */
  assert( iBlock>=0 && iBlock<mem5.nBlock );
  assert( ((u8 *)pOld-mem5.zPool)%mem5.szAtom==0 );
  assert( (mem5.aCtrl[iBlock] & CTRL_FREE)==0 );

  iLogsize = mem5.aCtrl[iBlock] & CTRL_LOGSIZE;
  size = 1<<iLogsize;
  assert( iBlock+size-1<(u32)mem5.nBlock );

  mem5.aCtrl[iBlock] |= CTRL_FREE;
  mem5.aCtrl[iBlock+size-1] |= CTRL_FREE;
  assert( mem5.currentCount>0 );
  assert( mem5.currentOut>=(size*mem5.szAtom) );
  mem5.currentCount--;
  mem5.currentOut -= size*mem5.szAtom;
  assert( mem5.currentOut>0 || mem5.currentCount==0 );
  assert( mem5.currentCount>0 || mem5.currentOut==0 );

  mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
  while( ALWAYS(iLogsize<LOGMAX) ){
    int iBuddy;
    if( (iBlock>>iLogsize) & 1 ){
      iBuddy = iBlock - size;
    }else{
      iBuddy = iBlock + size;
    }
    assert( iBuddy>=0 );

    memsys5Leave();
  }
  return (void*)p; 
}

/*
** Free memory.
**
** The outer layer memory allocator prevents this routine from
** being called with pPrior==0.
*/
static void memsys5Free(void *pPrior){

  assert( pPrior!=0 );


  memsys5Enter();
  memsys5FreeUnsafe(pPrior);
  memsys5Leave();  
}

/*
** Change the size of an existing memory allocation.
**
** The outer layer memory allocator prevents this routine from
** being called with pPrior==0.  
**
** nBytes is always a value obtained from a prior call to
** memsys5Round().  Hence nBytes is always a non-negative power
** of two.  If nBytes==0 that means that an oversize allocation
** (an allocation larger than 0x40000000) was requested and this
** routine should return 0 without freeing pPrior.
*/
static void *memsys5Realloc(void *pPrior, int nBytes){
  int nOld;
  void *p;
  assert( pPrior!=0 );
  assert( (nBytes&(nBytes-1))==0 );
  assert( nBytes>=0 );

  if( nBytes==0 ){

    return 0;
  }
  nOld = memsys5Size(pPrior);
  if( nBytes<=nOld ){
    return pPrior;
  }
  memsys5Enter();
  p = memsys5MallocUnsafe(nBytes);
  if( p ){
    memcpy(p, pPrior, nOld);
    memsys5FreeUnsafe(pPrior);
  }
  memsys5Leave();
  return p;
}

/*
** Round up a request size to the next valid allocation size.  If
** the allocation is too large to be handled by this allocation system,
** return 0.
**
** All allocations must be a power of two and must be expressed by a
** 32-bit signed integer.  Hence the largest allocation is 0x40000000
** or 1073741824 bytes.
*/
static int memsys5Roundup(int n){
  int iFullSz;
  if( n > 0x40000000 ) return 0;
  for(iFullSz=mem5.szAtom; iFullSz<n; iFullSz *= 2);
  return iFullSz;
}

/*
** Return the ceiling of the logarithm base 2 of iValue.
**
** Examples:   memsys5Log(1) -> 0
**             memsys5Log(2) -> 1
**             memsys5Log(4) -> 2
**             memsys5Log(5) -> 3
**             memsys5Log(8) -> 3
**             memsys5Log(9) -> 4
*/
static int memsys5Log(int iValue){
  int iLog;
  for(iLog=0; (1<<iLog)<iValue; iLog++);
  return iLog;
}

/*
** Initialize the memory allocator.
**
** This routine is not threadsafe.  The caller must be holding a mutex
** to prevent multiple threads from entering at the same time.
*/
static int memsys5Init(void *NotUsed){
  int ii;            /* Loop counter */
  int nByte;         /* Number of bytes of memory available to this allocator */
  u8 *zByte;         /* Memory usable by this allocator */
  int nMinLog;       /* Log base 2 of minimum allocation size in bytes */
  int iOffset;       /* An offset into mem5.aCtrl[] */

  UNUSED_PARAMETER(NotUsed);

  /* For the purposes of this routine, disable the mutex */
  mem5.mutex = 0;

  /* The size of a Mem5Link object must be a power of two.  Verify that
  ** this is case.
  */
  assert( (sizeof(Mem5Link)&(sizeof(Mem5Link)-1))==0 );

  nByte = sqlite3GlobalConfig.nHeap;
  zByte = (u8*)sqlite3GlobalConfig.pHeap;
  assert( zByte!=0 );  /* sqlite3_config() does not allow otherwise */

  nMinLog = memsys5Log(sqlite3GlobalConfig.mnReq);
  mem5.szAtom = (1<<nMinLog);
  while( (int)sizeof(Mem5Link)>mem5.szAtom ){
    mem5.szAtom = mem5.szAtom << 1;
  }

  mem5.nBlock = (nByte / (mem5.szAtom+sizeof(u8)));
  mem5.zPool = zByte;
  mem5.aCtrl = (u8 *)&mem5.zPool[mem5.nBlock*mem5.szAtom];

  for(ii=0; ii<=LOGMAX; ii++){
    mem5.aiFreelist[ii] = -1;
  }

  iOffset = 0;
  for(ii=LOGMAX; ii>=0; ii--){
    int nAlloc = (1<<ii);
    if( (iOffset+nAlloc)<=mem5.nBlock ){
      mem5.aCtrl[iOffset] = ii | CTRL_FREE;
      memsys5Link(iOffset, ii);
      iOffset += nAlloc;
    }
    assert((iOffset+nAlloc)>mem5.nBlock);
  }

  /* If a mutex is required for normal operation, allocate one */
  if( sqlite3GlobalConfig.bMemstat==0 ){
    mem5.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
  }

  return SQLITE_OK;
}

/*
** Deinitialize this module.
*/
static void memsys5Shutdown(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  mem5.mutex = 0;
  return;
}

#ifdef SQLITE_TEST
/*
** Open the file indicated and write a log of all unfreed memory 
** allocations into that log.
*/
SQLITE_PRIVATE void sqlite3Memsys5Dump(const char *zFilename){

  FILE *out;
  int i, j, n;
  int nMinLog;

  if( zFilename==0 || zFilename[0]==0 ){
    out = stdout;
  }else{
    out = fopen(zFilename, "w");
    if( out==0 ){
      fprintf(stderr, "** Unable to output memory debug output log: %s **\n",
                      zFilename);
      return;
    }
  }
  memsys5Enter();
  nMinLog = memsys5Log(mem5.szAtom);
  for(i=0; i<=LOGMAX && i+nMinLog<32; i++){
    for(n=0, j=mem5.aiFreelist[i]; j>=0; j = MEM5LINK(j)->next, n++){}
    fprintf(out, "freelist items of size %d: %d\n", mem5.szAtom << i, n);
  }
  fprintf(out, "mem5.nAlloc       = %llu\n", mem5.nAlloc);
  fprintf(out, "mem5.totalAlloc   = %llu\n", mem5.totalAlloc);
  fprintf(out, "mem5.totalExcess  = %llu\n", mem5.totalExcess);
  fprintf(out, "mem5.currentOut   = %u\n", mem5.currentOut);
  fprintf(out, "mem5.currentCount = %u\n", mem5.currentCount);
  fprintf(out, "mem5.maxOut       = %u\n", mem5.maxOut);
  fprintf(out, "mem5.maxCount     = %u\n", mem5.maxCount);
  fprintf(out, "mem5.maxRequest   = %u\n", mem5.maxRequest);
  memsys5Leave();
  if( out==stdout ){
    fflush(stdout);
  }else{
    fclose(out);
  }



}
#endif

/*
** This routine is the only routine in this file with external 
** linkage. It returns a pointer to a static sqlite3_mem_methods
** struct populated with the memsys5 methods.
*/
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void){

** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_LRU2
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to.  But SQLite will only request a recursive mutex in
** cases where it really needs one.  If a faster non-recursive mutex
** implementation is available on the host platform, the mutex subsystem
** might return such a mutex in response to SQLITE_MUTEX_FAST.
**
** The other allowed parameters to sqlite3_mutex_alloc() each return
** a pointer to a static preexisting mutex.  Six static mutexes are
** used by the current version of SQLite.  Future versions of SQLite
** may add additional static mutexes.  Static mutexes are for internal
** use by SQLite only.  Applications that use SQLite mutexes should
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
** SQLITE_MUTEX_RECURSIVE.
**
** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST

*/
static long winMutex_lock = 0;

static int winMutexInit(void){ 
  /* The first to increment to 1 does actual initialization */
  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
    int i;
    for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
      InitializeCriticalSection(&winMutex_staticMutexes[i].mutex);
    }
    winMutex_isInit = 1;
  }else{
    /* Someone else is in the process of initing the static mutexes */
    while( !winMutex_isInit ){
      Sleep(1);
    }
  }
  return SQLITE_OK; 
}

static int winMutexEnd(void){ 
  /* The first to decrement to 0 does actual shutdown 
  ** (which should be the last to shutdown.) */
  if( InterlockedCompareExchange(&winMutex_lock, 0, 1)==1 ){
    if( winMutex_isInit==1 ){
      int i;
      for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
        DeleteCriticalSection(&winMutex_staticMutexes[i].mutex);
      }
      winMutex_isInit = 0;
    }
  }
  return SQLITE_OK; 
}

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated.  SQLite
** will unwind its stack and return an error.  The argument
** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_LRU2
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to.  But SQLite will only request a recursive mutex in
** cases where it really needs one.  If a faster non-recursive mutex
** implementation is available on the host platform, the mutex subsystem
** might return such a mutex in response to SQLITE_MUTEX_FAST.
**
** The other allowed parameters to sqlite3_mutex_alloc() each return
** a pointer to a static preexisting mutex.  Six static mutexes are
** used by the current version of SQLite.  Future versions of SQLite
** may add additional static mutexes.  Static mutexes are for internal
** use by SQLite only.  Applications that use SQLite mutexes should
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
** SQLITE_MUTEX_RECURSIVE.
**
** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST

        InitializeCriticalSection(&p->mutex);
      }
      break;
    }
    default: {
      assert( winMutex_isInit==1 );
      assert( iType-2 >= 0 );
      assert( iType-2 < ArraySize(winMutex_staticMutexes) );
      p = &winMutex_staticMutexes[iType-2];
      p->id = iType;
      break;
    }
  }
  return p;
}

  sqlite3_uint64 iLimit;
  int overage;
  if( n<0 ){
    iLimit = 0;
  }else{
    iLimit = n;
  }
#ifndef SQLITE_OMIT_AUTOINIT
  sqlite3_initialize();
#endif
  if( iLimit>0 ){
    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, iLimit);
  }else{
    sqlite3MemoryAlarm(0, 0, 0);
  }
  overage = (int)(sqlite3_memory_used() - (i64)n);
  if( overage>0 ){

    return 0;
  }
  if( nBytes>=0x7fffff00 ){
    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
    return 0;
  }
  nOld = sqlite3MallocSize(pOld);



  nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
  if( nOld==nNew ){
    pNew = pOld;
  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED)+nNew-nOld >= 
          mem0.alarmThreshold ){
      sqlite3MallocAlarm(nNew-nOld);
    }
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmCallback ){
      sqlite3MallocAlarm(nBytes);
      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    }
    if( pNew ){
      nNew = sqlite3MallocSize(pNew);
      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
    }

    sqlite3_mutex_leave(mem0.mutex);
  }else{
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
  }
  return pNew;
}

/*
** The public interface to sqlite3Realloc.  Make sure that the memory
** subsystem is initialized prior to invoking sqliteRealloc.

  int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
  i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
  Bool zeroed;          /* True if zeroed out and ready for reuse */
  Bool rowidIsValid;    /* True if lastRowid is valid */
  Bool atFirst;         /* True if pointing to first entry */
  Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
  Bool nullRow;         /* True if pointing to a row with no data */


  Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
  Bool isTable;         /* True if a table requiring integer keys */
  Bool isIndex;         /* True if an index containing keys only - no data */
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
  Btree *pBt;           /* Separate file holding temporary table */

  int pseudoTableReg;   /* Register holding pseudotable content. */

  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
  int nField;           /* Number of fields in the header */
  i64 seqCount;         /* Sequence counter */
  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
  const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */

  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
  ** OP_IsUnique opcode on this cursor. */
  int seekResult;

  /* Cached information about the header for the data record that the
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date.
  **
  ** aRow might point to (ephemeral) data for the current row, or it might
  ** be NULL.
  */
  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
  int payloadSize;      /* Total number of bytes in the record */
  u32 *aType;           /* Type values for all entries in the record */
  u32 *aOffset;         /* Cached offsets to the start of each columns data */
  u8 *aRow;             /* Data for the current row, if all on one page */
};
typedef struct VdbeCursor VdbeCursor;

/*
** When a sub-program is executed (OP_Program), a structure of this type
** is allocated to store the current value of the program counter, as
** well as the current memory cell array and various other frame specific
** values stored in the Vdbe struct. When the sub-program is finished, 
** these values are copied back to the Vdbe from the VdbeFrame structure,
** restoring the state of the VM to as it was before the sub-program
** began executing.
**
** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
** is the parent of the current frame, or zero if the current frame
** is the main Vdbe program.
*/
typedef struct VdbeFrame VdbeFrame;
struct VdbeFrame {
  Vdbe *v;                /* VM this frame belongs to */
  int pc;                 /* Program Counter */
  Op *aOp;                /* Program instructions */
  int nOp;                /* Size of aOp array */
  Mem *aMem;              /* Array of memory cells */
  int nMem;               /* Number of entries in aMem */
  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
  u16 nCursor;            /* Number of entries in apCsr */
  void *token;            /* Copy of SubProgram.token */
  int nChildMem;          /* Number of memory cells for child frame */
  int nChildCsr;          /* Number of cursors for child frame */
  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
  int nChange;            /* Statement changes (Vdbe.nChanges)     */
  VdbeFrame *pParent;     /* Parent of this frame */
};

#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])

/*
** A value for VdbeCursor.cacheValid that means the cache is always invalid.
*/
#define CACHE_STALE 0

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem

*/
struct Mem {
  union {
    i64 i;              /* Integer value. */
    int nZero;          /* Used when bit MEM_Zero is set in flags */
    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
  } u;
  double r;           /* Real value */
  sqlite3 *db;        /* The associated database connection */
  char *z;            /* String or BLOB value */
  int n;              /* Number of characters in string value, excluding '\0' */
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */

*/
#define MEM_Null      0x0001   /* Value is NULL */
#define MEM_Str       0x0002   /* Value is a string */
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
#define MEM_TypeMask  0x00ff   /* Mask of type bits */

/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
** policy for Mem.z.  The MEM_Term flag tells us whether or not the
** string is \000 or \u0000 terminated
*/

*/
typedef struct Set Set;
struct Set {
  Hash hash;             /* A set is just a hash table */
  HashElem *prev;        /* Previously accessed hash elemen */
};
















/*
** An instance of the virtual machine.  This structure contains the complete
** state of the virtual machine.
**
** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
** is really a pointer to an instance of this structure.
**

  u8 okVar;               /* True if azVar[] has been initialized */
  u16 nVar;               /* Number of entries in aVar[] */
  Mem *aVar;              /* Values for the OP_Variable opcode. */
  char **azVar;           /* Name of variables */
  u32 magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
  u32 cacheCtr;           /* VdbeCursor row cache generation counter */



  int pc;                 /* The program counter */
  int rc;                 /* Value to return */
  char *zErrMsg;          /* Error message written here */
  u8 explain;             /* True if EXPLAIN present on SQL command */
  u8 changeCntOn;         /* True to update the change-counter */
  u8 expired;             /* True if the VM needs to be recompiled */
  u8 minWriteFileFormat;  /* Minimum file format for writable database files */

  int aCounter[2];        /* Counters used by sqlite3_stmt_status() */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */
  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
#ifdef SQLITE_DEBUG
  FILE *trace;            /* Write an execution trace here, if not NULL */
#endif
  VdbeFrame *pFrame;      /* Parent frame */
  int nFrame;             /* Number of frames in pFrame list */
};

/*
** The following are allowed values for Vdbe.magic
*/
#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */

SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
SQLITE_PRIVATE int sqlite3VdbeOpcodeHasProperty(int, int);
SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
SQLITE_PRIVATE int sqlite3VdbeReleaseBuffers(Vdbe *p);
#endif

#ifndef SQLITE_OMIT_SHARED_CACHE
SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
#else

    m.z = 0;
  }
  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
  return (m.flags & MEM_Dyn)!=0 ? m.z : sqlite3DbStrDup(db, m.z);
}

/*
** Convert a UTF-8 string to the UTF-16 encoding specified by parameter
** enc. A pointer to the new string is returned, and the value of *pnOut
** is set to the length of the returned string in bytes. The call should
** arrange to call sqlite3DbFree() on the returned pointer when it is
** no longer required.
** 
** If a malloc failure occurs, NULL is returned and the db.mallocFailed
** flag set.
*/
#ifdef SQLITE_ENABLE_STAT2
SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *db, u8 enc, char *z, int n, int *pnOut){
  Mem m;
  memset(&m, 0, sizeof(m));
  m.db = db;
  sqlite3VdbeMemSetStr(&m, z, n, SQLITE_UTF8, SQLITE_STATIC);
  if( sqlite3VdbeMemTranslate(&m, enc) ){
    assert( db->mallocFailed );
    return 0;
  }
  assert( m.z==m.zMalloc );
  *pnOut = m.n;
  return m.z;
}
#endif

/*
** pZ is a UTF-16 encoded unicode string at least nChar characters long.
** Return the number of bytes in the first nChar unicode characters
** in pZ.  nChar must be non-negative.
*/
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
  int c;

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**

*/
#ifdef SQLITE_HAVE_ISNAN
# include <math.h>
#endif

/*
** Routine needed to support the testcase() macro.

    while( sqlite3Isdigit(*z) ){ z += incr; }
    *realnum = 1;
  }
  return *z==0;
}

/*
** The string z[] is an ASCII representation of a real number.
** Convert this string to a double.
**
** This routine assumes that z[] really is a valid number.  If it
** is not, the result is undefined.
**
** This routine is used instead of the library atof() function because
** the library atof() might want to use "," as the decimal point instead
** of "." depending on how locale is set.  But that would cause problems
** for SQL.  So this routine always uses "." regardless of locale.
*/
SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult){
#ifndef SQLITE_OMIT_FLOATING_POINT

  const char *zBegin = z;
  /* sign * significand * (10 ^ (esign * exponent)) */
  int sign = 1;   /* sign of significand */
  i64 s = 0;      /* significand */
  int d = 0;      /* adjust exponent for shifting decimal point */
  int esign = 1;  /* sign of exponent */
  int e = 0;      /* exponent */
  double result;
  int nDigits = 0;

  /* skip leading spaces */
  while( sqlite3Isspace(*z) ) z++;
  /* get sign of significand */
  if( *z=='-' ){
    sign = -1;
    z++;
  }else if( *z=='+' ){
    z++;
  }
  /* skip leading zeroes */
  while( z[0]=='0' ) z++, nDigits++;


  /* copy max significant digits to significand */
  while( sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
    s = s*10 + (*z - '0');
    z++, nDigits++;
  }
  /* skip non-significant significand digits
  ** (increase exponent by d to shift decimal left) */
  while( sqlite3Isdigit(*z) ) z++, nDigits++, d++;

  /* if decimal point is present */
  if( *z=='.' ){

    z++;
    /* copy digits from after decimal to significand





    ** (decrease exponent by d to shift decimal right) */
    while( sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){

      s = s*10 + (*z - '0');

      z++, nDigits++, d--;
    }
    /* skip non-significant digits */
    while( sqlite3Isdigit(*z) ) z++, nDigits++;
  }


  /* if exponent is present */
  if( *z=='e' || *z=='E' ){



    z++;
    /* get sign of exponent */
    if( *z=='-' ){
      esign = -1;
      z++;
    }else if( *z=='+' ){
      z++;
    }
    /* copy digits to exponent */
    while( sqlite3Isdigit(*z) ){
      e = e*10 + (*z - '0');
      z++;
    }
  }

  /* adjust exponent by d, and update sign */
  e = (e*esign) + d;
  if( e<0 ) {
    esign = -1;
    e *= -1;
  } else {
    esign = 1;
  }

  /* if 0 significand */
  if( !s ) {
    /* In the IEEE 754 standard, zero is signed.
    ** Add the sign if we've seen at least one digit */
    result = (sign<0 && nDigits) ? -(double)0 : (double)0;
  } else {
    /* attempt to reduce exponent */
    if( esign>0 ){
      while( s<(LARGEST_INT64/10) && e>0 ) e--,s*=10;
    }else{
      while( !(s%10) && e>0 ) e--,s/=10;
    }

    /* adjust the sign of significand */
    s = sign<0 ? -s : s;

    /* if exponent, scale significand as appropriate
    ** and store in result. */
    if( e ){
      double scale = 1.0;
      /* attempt to handle extremely small/large numbers better */
      if( e>307 && e<342 ){
        while( e%308 ) { scale *= 1.0e+1; e -= 1; }
        if( esign<0 ){
          result = s / scale;
          result /= 1.0e+308;
        }else{
          result = s * scale;
          result *= 1.0e+308;
        }
      }else{
        /* 1.0e+22 is the largest power of 10 than can be 
        ** represented exactly. */
        while( e%22 ) { scale *= 1.0e+1; e -= 1; }
        while( e>0 ) { scale *= 1.0e+22; e -= 22; }
        if( esign<0 ){
          result = s / scale;
        }else{
          result = s * scale;
        }
      }
    } else {
      result = (double)s;
    }
  }

  /* store the result */
  *pResult = result;

  /* return number of characters used */
  return (int)(z - zBegin);
#else
  return sqlite3Atoi64(z, pResult);
#endif /* SQLITE_OMIT_FLOATING_POINT */
}

/*

}



#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
/*
** Translate a single byte of Hex into an integer.
** This routine only works if h really is a valid hexadecimal
** character:  0..9a..fA..F
*/
static u8 hexToInt(int h){
  assert( (h>='0' && h<='9') ||  (h>='a' && h<='f') ||  (h>='A' && h<='F') );
#ifdef SQLITE_ASCII
  h += 9*(1&(h>>6));
#endif

     /*  18 */ "Sort",
     /*  19 */ "Not",
     /*  20 */ "Copy",
     /*  21 */ "Trace",
     /*  22 */ "Function",
     /*  23 */ "IfNeg",
     /*  24 */ "Noop",
     /*  25 */ "Program",
     /*  26 */ "Return",
     /*  27 */ "NewRowid",
     /*  28 */ "Variable",
     /*  29 */ "String",
     /*  30 */ "RealAffinity",
     /*  31 */ "VRename",
     /*  32 */ "ParseSchema",
     /*  33 */ "VOpen",
     /*  34 */ "Close",
     /*  35 */ "CreateIndex",
     /*  36 */ "IsUnique",
     /*  37 */ "NotFound",
     /*  38 */ "Int64",
     /*  39 */ "MustBeInt",
     /*  40 */ "Halt",
     /*  41 */ "Rowid",
     /*  42 */ "IdxLT",
     /*  43 */ "AddImm",
     /*  44 */ "RowData",
     /*  45 */ "MemMax",
     /*  46 */ "NotExists",
     /*  47 */ "Gosub",
     /*  48 */ "Integer",
     /*  49 */ "Prev",
     /*  50 */ "RowSetRead",
     /*  51 */ "RowSetAdd",
     /*  52 */ "VColumn",
     /*  53 */ "CreateTable",
     /*  54 */ "Last",
     /*  55 */ "SeekLe",
     /*  56 */ "IncrVacuum",
     /*  57 */ "IdxRowid",
     /*  58 */ "ResetCount",
     /*  59 */ "Yield",
     /*  60 */ "DropTrigger",
     /*  61 */ "DropIndex",
     /*  62 */ "Param",
     /*  63 */ "IdxGE",
     /*  64 */ "IdxDelete",
     /*  65 */ "Vacuum",
     /*  66 */ "Or",
     /*  67 */ "And",
     /*  68 */ "IfNot",
     /*  69 */ "DropTable",

     /*  94 */ "String8",
     /*  95 */ "Compare",
     /*  96 */ "Goto",
     /*  97 */ "TableLock",
     /*  98 */ "Clear",
     /*  99 */ "VerifyCookie",
     /* 100 */ "AggStep",
     /* 101 */ "Transaction",
     /* 102 */ "VFilter",
     /* 103 */ "VDestroy",
     /* 104 */ "Next",
     /* 105 */ "Count",
     /* 106 */ "IdxInsert",
     /* 107 */ "SeekGe",
     /* 108 */ "Insert",
     /* 109 */ "Destroy",
     /* 110 */ "ReadCookie",
     /* 111 */ "RowSetTest",
     /* 112 */ "LoadAnalysis",
     /* 113 */ "Explain",
     /* 114 */ "HaltIfNull",
     /* 115 */ "OpenPseudo",
     /* 116 */ "OpenEphemeral",
     /* 117 */ "Null",
     /* 118 */ "Move",
     /* 119 */ "Blob",
     /* 120 */ "Rewind",
     /* 121 */ "SeekGt",
     /* 122 */ "VBegin",
     /* 123 */ "VUpdate",
     /* 124 */ "IfZero",
     /* 125 */ "VCreate",
     /* 126 */ "Found",
     /* 127 */ "IfPos",
     /* 128 */ "NullRow",
     /* 129 */ "Jump",
     /* 130 */ "Real",
     /* 131 */ "Permutation",
     /* 132 */ "NotUsed_132",
     /* 133 */ "NotUsed_133",
     /* 134 */ "NotUsed_134",
     /* 135 */ "NotUsed_135",
     /* 136 */ "NotUsed_136",
     /* 137 */ "NotUsed_137",
     /* 138 */ "NotUsed_138",
     /* 139 */ "NotUsed_139",
     /* 140 */ "NotUsed_140",

**   *  sqlite3_file methods not associated with locking.
**   *  Definitions of sqlite3_io_methods objects for all locking
**      methods plus "finder" functions for each locking method.
**   *  sqlite3_vfs method implementations.
**   *  Locking primitives for the proxy uber-locking-method. (MacOSX only)
**   *  Definitions of sqlite3_vfs objects for all locking methods
**      plus implementations of sqlite3_os_init() and sqlite3_os_end().


*/
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** There are various methods for file locking used for concurrency
** control:
**

/*
** Only set the lastErrno if the error code is a real error and not 
** a normal expected return code of SQLITE_BUSY or SQLITE_OK
*/
#define IS_LOCK_ERROR(x)  ((x != SQLITE_OK) && (x != SQLITE_BUSY))


/*
** Sometimes, after a file handle is closed by SQLite, the file descriptor
** cannot be closed immediately. In these cases, instances of the following
** structure are used to store the file descriptor while waiting for an
** opportunity to either close or reuse it.
*/
typedef struct UnixUnusedFd UnixUnusedFd;
struct UnixUnusedFd {
  int fd;                   /* File descriptor to close */
  int flags;                /* Flags this file descriptor was opened with */
  UnixUnusedFd *pNext;      /* Next unused file descriptor on same file */
};

/*
** The unixFile structure is subclass of sqlite3_file specific to the unix
** VFS implementations.
*/
typedef struct unixFile unixFile;
struct unixFile {
  sqlite3_io_methods const *pMethod;  /* Always the first entry */
  struct unixOpenCnt *pOpen;       /* Info about all open fd's on this inode */
  struct unixLockInfo *pLock;      /* Info about locks on this inode */
  int h;                           /* The file descriptor */
  int dirfd;                       /* File descriptor for the directory */
  unsigned char locktype;          /* The type of lock held on this fd */
  int lastErrno;                   /* The unix errno from the last I/O error */
  void *lockingContext;            /* Locking style specific state */
  UnixUnusedFd *pUnused;           /* Pre-allocated UnixUnusedFd */
  int fileFlags;                   /* Miscellanous flags */
#if SQLITE_ENABLE_LOCKING_STYLE
  int openFlags;                   /* The flags specified at open() */
#endif
#if SQLITE_THREADSAFE && defined(__linux__)
  pthread_t tid;                   /* The thread that "owns" this unixFile */
#endif
#if OS_VXWORKS

  ** occur if a file is updated without also updating the transaction
  ** counter.  This test is made to avoid new problems similar to the
  ** one described by ticket #3584. 
  */
  unsigned char transCntrChng;   /* True if the transaction counter changed */
  unsigned char dbUpdate;        /* True if any part of database file changed */
  unsigned char inNormalWrite;   /* True if in a normal write operation */





#endif
#ifdef SQLITE_TEST
  /* In test mode, increase the size of this structure a bit so that 
  ** it is larger than the struct CrashFile defined in test6.c.
  */
  char aPadding[32];
#endif
};

/*
** The following macros define bits in unixFile.fileFlags
*/
#define SQLITE_WHOLE_FILE_LOCKING  0x0001   /* Use whole-file locking */

/*
** Include code that is common to all os_*.c files
*/
/************** Include os_common.h in the middle of os_unix.c ***************/
/************** Begin file os_common.h ***************************************/
/*
** 2004 May 22

#define threadid pthread_self()
#else
#define threadid 0
#endif


/*
** Helper functions to obtain and relinquish the global mutex. The
** global mutex is used to protect the unixOpenCnt, unixLockInfo and
** vxworksFileId objects used by this file, all of which may be 
** shared by multiple threads.
**
** Function unixMutexHeld() is used to assert() that the global mutex 
** is held when required. This function is only used as part of assert() 
** statements. e.g.
**
**   unixEnterMutex()
**     assert( unixMutexHeld() );
**   unixEnterLeave()
*/
static void unixEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
static void unixLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#ifdef SQLITE_DEBUG
static int unixMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#endif


#ifdef SQLITE_DEBUG
/*
** Helper function for printing out trace information from debugging
** binaries. This returns the string represetation of the supplied
** integer lock-type.
*/
static const char *locktypeName(int locktype){
  switch( locktype ){
    case NO_LOCK: return "NONE";
    case SHARED_LOCK: return "SHARED";
    case RESERVED_LOCK: return "RESERVED";
    case PENDING_LOCK: return "PENDING";
    case EXCLUSIVE_LOCK: return "EXCLUSIVE";
  }
  return "ERROR";
}
#endif

#ifdef SQLITE_LOCK_TRACE
/*

** The close() system call would only occur when the last database
** using the file closes.
*/
struct unixOpenCnt {
  struct unixFileId fileId;   /* The lookup key */
  int nRef;                   /* Number of pointers to this structure */
  int nLock;                  /* Number of outstanding locks */
  UnixUnusedFd *pUnused;      /* Unused file descriptors to close */

#if OS_VXWORKS
  sem_t *pSem;                     /* Named POSIX semaphore */
  char aSemName[MAX_PATHNAME+2];   /* Name of that semaphore */
#endif
  struct unixOpenCnt *pNext, *pPrev;   /* List of all unixOpenCnt objects */
};

/*
** Lists of all unixLockInfo and unixOpenCnt objects.  These used to be hash
** tables.  But the number of objects is rarely more than a dozen and

  if( d.result!=0 ) return;
  threadsOverrideEachOthersLocks = (d.lock.l_type==F_UNLCK);
}
#endif /* SQLITE_THREADSAFE && defined(__linux__) */

/*
** Release a unixLockInfo structure previously allocated by findLockInfo().
**
** The mutex entered using the unixEnterMutex() function must be held
** when this function is called.
*/
static void releaseLockInfo(struct unixLockInfo *pLock){
  assert( unixMutexHeld() );
  if( pLock ){
    pLock->nRef--;
    if( pLock->nRef==0 ){
      if( pLock->pPrev ){
        assert( pLock->pPrev->pNext==pLock );
        pLock->pPrev->pNext = pLock->pNext;
      }else{

      sqlite3_free(pLock);
    }
  }
}

/*
** Release a unixOpenCnt structure previously allocated by findLockInfo().
**
** The mutex entered using the unixEnterMutex() function must be held
** when this function is called.
*/
static void releaseOpenCnt(struct unixOpenCnt *pOpen){
  assert( unixMutexHeld() );
  if( pOpen ){
    pOpen->nRef--;
    if( pOpen->nRef==0 ){
      if( pOpen->pPrev ){
        assert( pOpen->pPrev->pNext==pOpen );
        pOpen->pPrev->pNext = pOpen->pNext;
      }else{
        assert( openList==pOpen );
        openList = pOpen->pNext;
      }
      if( pOpen->pNext ){
        assert( pOpen->pNext->pPrev==pOpen );
        pOpen->pNext->pPrev = pOpen->pPrev;
      }
      assert( !pOpen->pUnused );
      sqlite3_free(pOpen);
    }
  }
}

/*
** Given a file descriptor, locate unixLockInfo and unixOpenCnt structures that
** describes that file descriptor.  Create new ones if necessary.  The
** return values might be uninitialized if an error occurs.
**
** The mutex entered using the unixEnterMutex() function must be held
** when this function is called.
**
** Return an appropriate error code.
*/
static int findLockInfo(
  unixFile *pFile,               /* Unix file with file desc used in the key */
  struct unixLockInfo **ppLock,  /* Return the unixLockInfo structure here */
  struct unixOpenCnt **ppOpen    /* Return the unixOpenCnt structure here */
){
  int rc;                        /* System call return code */
  int fd;                        /* The file descriptor for pFile */
  struct unixLockKey lockKey;    /* Lookup key for the unixLockInfo structure */
  struct unixFileId fileId;      /* Lookup key for the unixOpenCnt struct */
  struct stat statbuf;           /* Low-level file information */
  struct unixLockInfo *pLock = 0;/* Candidate unixLockInfo object */
  struct unixOpenCnt *pOpen;     /* Candidate unixOpenCnt object */

  assert( unixMutexHeld() );

  /* Get low-level information about the file that we can used to
  ** create a unique name for the file.
  */
  fd = pFile->h;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ){

    if( pOpen==0 ){
      pOpen = sqlite3_malloc( sizeof(*pOpen) );
      if( pOpen==0 ){
        releaseLockInfo(pLock);
        rc = SQLITE_NOMEM;
        goto exit_findlockinfo;
      }
      memset(pOpen, 0, sizeof(*pOpen));
      pOpen->fileId = fileId;
      pOpen->nRef = 1;



      pOpen->pNext = openList;

      if( openList ) openList->pPrev = pOpen;
      openList = pOpen;




    }else{
      pOpen->nRef++;
    }
    *ppOpen = pOpen;
  }

exit_findlockinfo:

  
  unixLeaveMutex();
  OSTRACE4("TEST WR-LOCK %d %d %d\n", pFile->h, rc, reserved);

  *pResOut = reserved;
  return rc;
}

/*
** Perform a file locking operation on a range of bytes in a file.
** The "op" parameter should be one of F_RDLCK, F_WRLCK, or F_UNLCK.
** Return 0 on success or -1 for failure.  On failure, write the error
** code into *pErrcode.
**
** If the SQLITE_WHOLE_FILE_LOCKING bit is clear, then only lock
** the range of bytes on the locking page between SHARED_FIRST and
** SHARED_SIZE.  If SQLITE_WHOLE_FILE_LOCKING is set, then lock all
** bytes from 0 up to but not including PENDING_BYTE, and all bytes
** that follow SHARED_FIRST.
**
** In other words, of SQLITE_WHOLE_FILE_LOCKING if false (the historical
** default case) then only lock a small range of bytes from SHARED_FIRST
** through SHARED_FIRST+SHARED_SIZE-1.  But if SQLITE_WHOLE_FILE_LOCKING is
** true then lock every byte in the file except for PENDING_BYTE and
** RESERVED_BYTE.
**
** SQLITE_WHOLE_FILE_LOCKING=true overlaps SQLITE_WHOLE_FILE_LOCKING=false
** and so the locking schemes are compatible.  One type of lock will
** effectively exclude the other type.  The reason for using the
** SQLITE_WHOLE_FILE_LOCKING=true is that by indicating the full range
** of bytes to be read or written, we give hints to NFS to help it
** maintain cache coherency.  On the other hand, whole file locking
** is slower, so we don't want to use it except for NFS.
*/
static int rangeLock(unixFile *pFile, int op, int *pErrcode){
  struct flock lock;
  int rc;
  lock.l_type = op;
  lock.l_start = SHARED_FIRST;
  lock.l_whence = SEEK_SET;
  if( (pFile->fileFlags & SQLITE_WHOLE_FILE_LOCKING)==0 ){
    lock.l_len = SHARED_SIZE;
    rc = fcntl(pFile->h, F_SETLK, &lock);
    *pErrcode = errno;
  }else{
    lock.l_len = 0;
    rc = fcntl(pFile->h, F_SETLK, &lock);
    *pErrcode = errno;
    if( NEVER(op==F_UNLCK) || rc!=(-1) ){
      lock.l_start = 0;
      lock.l_len = PENDING_BYTE;
      rc = fcntl(pFile->h, F_SETLK, &lock);
      if( ALWAYS(op!=F_UNLCK) && rc==(-1) ){
        *pErrcode = errno;
        lock.l_type = F_UNLCK;
        lock.l_start = SHARED_FIRST;
        lock.l_len = 0;
        fcntl(pFile->h, F_SETLK, &lock);
      }
    }
  }
  return rc;
}

/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK

  ** locking a random byte from a range, concurrent SHARED locks may exist
  ** even if the locking primitive used is always a write-lock.
  */
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  struct unixLockInfo *pLock = pFile->pLock;
  struct flock lock;
  int s = 0;
  int tErrno;

  assert( pFile );
  OSTRACE7("LOCK    %d %s was %s(%s,%d) pid=%d\n", pFile->h,
      locktypeName(locktype), locktypeName(pFile->locktype),
      locktypeName(pLock->locktype), pLock->cnt , getpid());

  /* If there is already a lock of this type or more restrictive on the
  ** unixFile, do nothing. Don't use the end_lock: exit path, as
  ** unixEnterMutex() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    OSTRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
            locktypeName(locktype));
    return SQLITE_OK;
  }

  /* Make sure the locking sequence is correct.
  **  (1) We never move from unlocked to anything higher than shared lock.
  **  (2) SQLite never explicitly requests a pendig lock.
  **  (3) A shared lock is always held when a reserve lock is requested.
  */
  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
  assert( locktype!=PENDING_LOCK );
  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );

  /* This mutex is needed because pFile->pLock is shared across threads
  */

    assert( pLock->cnt>0 );
    pFile->locktype = SHARED_LOCK;
    pLock->cnt++;
    pFile->pOpen->nLock++;
    goto end_lock;
  }





  /* A PENDING lock is needed before acquiring a SHARED lock and before
  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
  ** be released.
  */
  lock.l_len = 1L;
  lock.l_whence = SEEK_SET;
  if( locktype==SHARED_LOCK 
      || (locktype==EXCLUSIVE_LOCK && pFile->locktype<PENDING_LOCK)
  ){
    lock.l_type = (locktype==SHARED_LOCK?F_RDLCK:F_WRLCK);
    lock.l_start = PENDING_BYTE;
    s = fcntl(pFile->h, F_SETLK, &lock);
    if( s==(-1) ){
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){
        pFile->lastErrno = tErrno;
      }
      goto end_lock;
    }
  }


  /* If control gets to this point, then actually go ahead and make
  ** operating system calls for the specified lock.
  */
  if( locktype==SHARED_LOCK ){

    assert( pLock->cnt==0 );
    assert( pLock->locktype==0 );

    /* Now get the read-lock */



    s = rangeLock(pFile, F_RDLCK, &tErrno);

    /* Drop the temporary PENDING lock */
    lock.l_start = PENDING_BYTE;
    lock.l_len = 1L;
    lock.l_type = F_UNLCK;
    if( fcntl(pFile->h, F_SETLK, &lock)!=0 ){
      if( s != -1 ){
        /* This could happen with a network mount */

    ** already.
    */
    assert( 0!=pFile->locktype );
    lock.l_type = F_WRLCK;
    switch( locktype ){
      case RESERVED_LOCK:
        lock.l_start = RESERVED_BYTE;
        s = fcntl(pFile->h, F_SETLK, &lock);
        tErrno = errno;
        break;
      case EXCLUSIVE_LOCK:


        s = rangeLock(pFile, F_WRLCK, &tErrno);
        break;
      default:
        assert(0);
    }

    if( s==(-1) ){

      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){
        pFile->lastErrno = tErrno;
      }
    }
  }
  

end_lock:
  unixLeaveMutex();
  OSTRACE4("LOCK    %d %s %s\n", pFile->h, locktypeName(locktype), 
      rc==SQLITE_OK ? "ok" : "failed");
  return rc;
}

/*
** Close all file descriptors accumuated in the unixOpenCnt->pUnused list.
** If all such file descriptors are closed without error, the list is
** cleared and SQLITE_OK returned.
**
** Otherwise, if an error occurs, then successfully closed file descriptor
** entries are removed from the list, and SQLITE_IOERR_CLOSE returned. 
** not deleted and SQLITE_IOERR_CLOSE returned.
*/ 
static int closePendingFds(unixFile *pFile){
  int rc = SQLITE_OK;
  struct unixOpenCnt *pOpen = pFile->pOpen;
  UnixUnusedFd *pError = 0;
  UnixUnusedFd *p;
  UnixUnusedFd *pNext;
  for(p=pOpen->pUnused; p; p=pNext){
    pNext = p->pNext;
    if( close(p->fd) ){
      pFile->lastErrno = errno;
      rc = SQLITE_IOERR_CLOSE;
      p->pNext = pError;
      pError = p;
    }else{
      sqlite3_free(p);
    }
  }
  pOpen->pUnused = pError;
  return rc;
}

/*
** Add the file descriptor used by file handle pFile to the corresponding
** pUnused list.
*/
static void setPendingFd(unixFile *pFile){
  struct unixOpenCnt *pOpen = pFile->pOpen;
  UnixUnusedFd *p = pFile->pUnused;
  p->pNext = pOpen->pUnused;
  pOpen->pUnused = p;
  pFile->h = -1;
  pFile->pUnused = 0;
}

/*
** Lower the locking level on file descriptor pFile to locktype.  locktype
** must be either NO_LOCK or SHARED_LOCK.
**
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
*/
static int unixUnlock(sqlite3_file *id, int locktype){
  unixFile *pFile = (unixFile*)id; /* The open file */
  struct unixLockInfo *pLock;      /* Structure describing current lock state */
  struct flock lock;               /* Information passed into fcntl() */
  int rc = SQLITE_OK;              /* Return code from this interface */

  int h;                           /* The underlying file descriptor */
  int tErrno;                      /* Error code from system call errors */

  assert( pFile );
  OSTRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", pFile->h, locktype,
      pFile->locktype, pFile->pLock->locktype, pFile->pLock->cnt, getpid());

  assert( locktype<=SHARED_LOCK );
  if( pFile->locktype<=locktype ){

         || pFile->dbUpdate==0
         || pFile->transCntrChng==1 );
    pFile->inNormalWrite = 0;
#endif


    if( locktype==SHARED_LOCK ){




      if( rangeLock(pFile, F_RDLCK, &tErrno)==(-1) ){

        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
        if( IS_LOCK_ERROR(rc) ){
          pFile->lastErrno = tErrno;
        }
        goto end_unlock;
      }
    }
    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = PENDING_BYTE;
    lock.l_len = 2L;  assert( PENDING_BYTE+1==RESERVED_BYTE );
    if( fcntl(h, F_SETLK, &lock)!=(-1) ){
      pLock->locktype = SHARED_LOCK;
    }else{
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
      if( IS_LOCK_ERROR(rc) ){
        pFile->lastErrno = tErrno;
      }
      goto end_unlock;
    }
  }
  if( locktype==NO_LOCK ){
    struct unixOpenCnt *pOpen;


    /* Decrement the shared lock counter.  Release the lock using an
    ** OS call only when all threads in this same process have released
    ** the lock.
    */
    pLock->cnt--;
    if( pLock->cnt==0 ){
      lock.l_type = F_UNLCK;
      lock.l_whence = SEEK_SET;
      lock.l_start = lock.l_len = 0L;
      SimulateIOErrorBenign(1);
      SimulateIOError( h=(-1) )
      SimulateIOErrorBenign(0);
      if( fcntl(h, F_SETLK, &lock)!=(-1) ){
        pLock->locktype = NO_LOCK;
      }else{
        tErrno = errno;
        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
        if( IS_LOCK_ERROR(rc) ){
          pFile->lastErrno = tErrno;
        }
        pLock->locktype = NO_LOCK;
        pFile->locktype = NO_LOCK;
      }
    }

    /* Decrement the count of locks against this same file.  When the
    ** count reaches zero, close any other file descriptors whose close
    ** was deferred because of outstanding locks.
    */
    pOpen = pFile->pOpen;
    pOpen->nLock--;
    assert( pOpen->nLock>=0 );
    if( pOpen->nLock==0 ){















      int rc2 = closePendingFds(pFile);



      if( rc==SQLITE_OK ){
        rc = rc2;
      }
    }
  }
	
end_unlock:
  unixLeaveMutex();
  if( rc==SQLITE_OK ) pFile->locktype = locktype;
  return rc;

      }
      vxworksReleaseFileId(pFile->pId);
      pFile->pId = 0;
    }
#endif
    OSTRACE2("CLOSE   %-3d\n", pFile->h);
    OpenCounter(-1);
    sqlite3_free(pFile->pUnused);
    memset(pFile, 0, sizeof(unixFile));
  }
  return SQLITE_OK;
}

/*
** Close a file.
*/
static int unixClose(sqlite3_file *id){
  int rc = SQLITE_OK;
  if( id ){
    unixFile *pFile = (unixFile *)id;
    unixUnlock(id, NO_LOCK);
    unixEnterMutex();
    if( pFile->pOpen && pFile->pOpen->nLock ){
      /* If there are outstanding locks, do not actually close the file just
      ** yet because that would clear those locks.  Instead, add the file
      ** descriptor to pOpen->pUnused list.  It will be automatically closed 
      ** when the last lock is cleared.
      */








      setPendingFd(pFile);


    }
    releaseLockInfo(pFile->pLock);
    releaseOpenCnt(pFile->pOpen);
    rc = closeUnixFile(id);
    unixLeaveMutex();
  }
  return rc;

/******************* End of the no-op lock implementation *********************
******************************************************************************/

/******************************************************************************
************************* Begin dot-file Locking ******************************
**
** The dotfile locking implementation uses the existance of separate lock
** files in order to control access to the database.  This works on just
** about every filesystem imaginable.  But there are serious downsides:
**
**    (1)  There is zero concurrency.  A single reader blocks all other
**         connections from reading or writing the database.
**
**    (2)  An application crash or power loss can leave stale lock files

  }

  if( rc==SQLITE_OK ){
    if( locktype==NO_LOCK ){
      struct unixOpenCnt *pOpen = pFile->pOpen;
      pOpen->nLock--;
      assert( pOpen->nLock>=0 );
      if( pOpen->nLock==0 ){












        rc = closePendingFds(pFile);


      }
    }
  }
  unixLeaveMutex();
  if( rc==SQLITE_OK ){
    pFile->locktype = locktype;
  }
  return rc;
}

/*
** Close a file & cleanup AFP specific locking context 
*/
static int afpClose(sqlite3_file *id) {
  if( id ){
    unixFile *pFile = (unixFile*)id;
    afpUnlock(id, NO_LOCK);
    unixEnterMutex();
    if( pFile->pOpen && pFile->pOpen->nLock ){
      /* If there are outstanding locks, do not actually close the file just
      ** yet because that would clear those locks.  Instead, add the file
      ** descriptor to pOpen->aPending.  It will be automatically closed when
      ** the last lock is cleared.
      */








      setPendingFd(pFile);


    }
    releaseOpenCnt(pFile->pOpen);
    sqlite3_free(pFile->lockingContext);
    closeUnixFile(id);
    unixLeaveMutex();
  }
  return SQLITE_OK;

*/
static int unixRead(
  sqlite3_file *id, 
  void *pBuf, 
  int amt,
  sqlite3_int64 offset
){
  unixFile *pFile = (unixFile *)id;
  int got;
  assert( id );

  /* If this is a database file (not a journal, master-journal or temp
  ** file), the bytes in the locking range should never be read or written. */
  assert( pFile->pUnused==0
       || offset>=PENDING_BYTE+512
       || offset+amt<=PENDING_BYTE 
  );

  got = seekAndRead(pFile, offset, pBuf, amt);
  if( got==amt ){
    return SQLITE_OK;
  }else if( got<0 ){
    /* lastErrno set by seekAndRead */
    return SQLITE_IOERR_READ;
  }else{
    pFile->lastErrno = 0; /* not a system error */
    /* Unread parts of the buffer must be zero-filled */
    memset(&((char*)pBuf)[got], 0, amt-got);
    return SQLITE_IOERR_SHORT_READ;
  }
}

/*

*/
static int unixWrite(
  sqlite3_file *id, 
  const void *pBuf, 
  int amt,
  sqlite3_int64 offset 
){
  unixFile *pFile = (unixFile*)id;
  int wrote = 0;
  assert( id );
  assert( amt>0 );

  /* If this is a database file (not a journal, master-journal or temp
  ** file), the bytes in the locking range should never be read or written. */
  assert( pFile->pUnused==0
       || offset>=PENDING_BYTE+512
       || offset+amt<=PENDING_BYTE 
  );

#ifndef NDEBUG
  /* If we are doing a normal write to a database file (as opposed to
  ** doing a hot-journal rollback or a write to some file other than a
  ** normal database file) then record the fact that the database
  ** has changed.  If the transaction counter is modified, record that
  ** fact too.
  */
  if( pFile->inNormalWrite ){

    pFile->dbUpdate = 1;  /* The database has been modified */
    if( offset<=24 && offset+amt>=27 ){
      int rc;
      char oldCntr[4];
      SimulateIOErrorBenign(1);
      rc = seekAndRead(pFile, 24, oldCntr, 4);
      SimulateIOErrorBenign(0);
      if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
        pFile->transCntrChng = 1;  /* The transaction counter has changed */
      }
    }
  }
#endif

  while( amt>0 && (wrote = seekAndWrite(pFile, offset, pBuf, amt))>0 ){
    amt -= wrote;
    offset += wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  SimulateIOError(( wrote=(-1), amt=1 ));
  SimulateDiskfullError(( wrote=0, amt=1 ));
  if( amt>0 ){
    if( wrote<0 ){
      /* lastErrno set by seekAndWrite */
      return SQLITE_IOERR_WRITE;
    }else{
      pFile->lastErrno = 0; /* not a system error */
      return SQLITE_FULL;
    }
  }
  return SQLITE_OK;
}

#ifdef SQLITE_TEST

** looks at the filesystem type and tries to guess the best locking
** strategy from that.
**
** For finder-funtion F, two objects are created:
**
**    (1) The real finder-function named "FImpt()".
**
**    (2) A constant pointer to this function named just "F".
**
**
** A pointer to the F pointer is used as the pAppData value for VFS
** objects.  We have to do this instead of letting pAppData point
** directly at the finder-function since C90 rules prevent a void*
** from be cast into a function pointer.
**

   LOCK,                       /* xLock */                                   \
   UNLOCK,                     /* xUnlock */                                 \
   CKLOCK,                     /* xCheckReservedLock */                      \
   unixFileControl,            /* xFileControl */                            \
   unixSectorSize,             /* xSectorSize */                             \
   unixDeviceCharacteristics   /* xDeviceCapabilities */                     \
};                                                                           \
static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
  UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
  return &METHOD;                                                            \
}                                                                            \
static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p)    \
    = FINDER##Impl;

/*
** Here are all of the sqlite3_io_methods objects for each of the
** locking strategies.  Functions that return pointers to these methods
** are also created.
*/

  afpClose,                 /* xClose method */
  afpLock,                  /* xLock method */
  afpUnlock,                /* xUnlock method */
  afpCheckReservedLock      /* xCheckReservedLock method */
)
#endif

/*
** The "Whole File Locking" finder returns the same set of methods as
** the posix locking finder.  But it also sets the SQLITE_WHOLE_FILE_LOCKING
** flag to force the posix advisory locks to cover the whole file instead
** of just a small span of bytes near the 1GiB boundary.  Whole File Locking
** is useful on NFS-mounted files since it helps NFS to maintain cache
** coherency.  But it is a detriment to other filesystems since it runs
** slower.
*/
static const sqlite3_io_methods *posixWflIoFinderImpl(const char*z, unixFile*p){
  UNUSED_PARAMETER(z);
  p->fileFlags = SQLITE_WHOLE_FILE_LOCKING;
  return &posixIoMethods;
}
static const sqlite3_io_methods 
  *(*const posixWflIoFinder)(const char*,unixFile *p) = posixWflIoFinderImpl;

/*
** The proxy locking method is a "super-method" in the sense that it
** opens secondary file descriptors for the conch and lock files and
** it uses proxy, dot-file, AFP, and flock() locking methods on those
** secondary files.  For this reason, the division that implements
** proxy locking is located much further down in the file.  But we need
** to go ahead and define the sqlite3_io_methods and finder function

** for the database file "filePath".  It then returns the sqlite3_io_methods
** object that implements that strategy.
**
** This is for MacOSX only.
*/
static const sqlite3_io_methods *autolockIoFinderImpl(
  const char *filePath,    /* name of the database file */
  unixFile *pNew           /* open file object for the database file */
){
  static const struct Mapping {
    const char *zFilesystem;              /* Filesystem type name */
    const sqlite3_io_methods *pMethods;   /* Appropriate locking method */
  } aMap[] = {
    { "hfs",    &posixIoMethods },
    { "ufs",    &posixIoMethods },

  ** Test byte-range lock using fcntl(). If the call succeeds, 
  ** assume that the file-system supports POSIX style locks. 
  */
  lockInfo.l_len = 1;
  lockInfo.l_start = 0;
  lockInfo.l_whence = SEEK_SET;
  lockInfo.l_type = F_RDLCK;
  if( fcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
    pNew->fileFlags = SQLITE_WHOLE_FILE_LOCKING;
    return &posixIoMethods;
  }else{
    return &dotlockIoMethods;
  }
}
static const sqlite3_io_methods 
  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;

#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */

#if OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE
/* 
** This "finder" function attempts to determine the best locking strategy 
** for the database file "filePath".  It then returns the sqlite3_io_methods
** object that implements that strategy.
**
** This is for VXWorks only.
*/
static const sqlite3_io_methods *autolockIoFinderImpl(
  const char *filePath,    /* name of the database file */
  unixFile *pNew           /* the open file object */
){
  struct flock lockInfo;

  if( !filePath ){
    /* If filePath==NULL that means we are dealing with a transient file
    ** that does not need to be locked. */
    return &nolockIoMethods;
  }

  /* Test if fcntl() is supported and use POSIX style locks.
  ** Otherwise fall back to the named semaphore method.
  */
  lockInfo.l_len = 1;
  lockInfo.l_start = 0;
  lockInfo.l_whence = SEEK_SET;
  lockInfo.l_type = F_RDLCK;
  if( fcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
    return &posixIoMethods;
  }else{
    return &semIoMethods;
  }
}
static const sqlite3_io_methods 
  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;

#endif /* OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE */

/*
** An abstract type for a pointer to a IO method finder function:
*/
typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);


/****************************************************************************
**************************** sqlite3_vfs methods ****************************
**
** This division contains the implementation of methods on the
** sqlite3_vfs object.

  const sqlite3_io_methods *pLockingStyle;
  unixFile *pNew = (unixFile *)pId;
  int rc = SQLITE_OK;

  assert( pNew->pLock==NULL );
  assert( pNew->pOpen==NULL );

  /* Parameter isDelete is only used on vxworks. Express this explicitly 
  ** here to prevent compiler warnings about unused parameters.

  */

  UNUSED_PARAMETER(isDelete);


  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);    
  pNew->h = h;
  pNew->dirfd = dirfd;
  SET_THREADID(pNew);
  pNew->fileFlags = 0;

#if OS_VXWORKS
  pNew->pId = vxworksFindFileId(zFilename);
  if( pNew->pId==0 ){
    noLock = 1;
    rc = SQLITE_NOMEM;
  }
#endif

  if( noLock ){
    pLockingStyle = &nolockIoMethods;
  }else{
    pLockingStyle = (**(finder_type*)pVfs->pAppData)(zFilename, pNew);
#if SQLITE_ENABLE_LOCKING_STYLE
    /* Cache zFilename in the locking context (AFP and dotlock override) for
    ** proxyLock activation is possible (remote proxy is based on db name)
    ** zFilename remains valid until file is closed, to support */
    pNew->lockingContext = (void*)zFilename;
#endif
  }

  if( pLockingStyle == &posixIoMethods ){
    unixEnterMutex();
    rc = findLockInfo(pNew, &pNew->pLock, &pNew->pOpen);
    if( rc!=SQLITE_OK ){
      /* If an error occured in findLockInfo(), close the file descriptor
      ** immediately, before releasing the mutex. findLockInfo() may fail
      ** in two scenarios:
      **
      **   (a) A call to fstat() failed.
      **   (b) A malloc failed.
      **
      ** Scenario (b) may only occur if the process is holding no other
      ** file descriptors open on the same file. If there were other file
      ** descriptors on this file, then no malloc would be required by
      ** findLockInfo(). If this is the case, it is quite safe to close
      ** handle h - as it is guaranteed that no posix locks will be released
      ** by doing so.
      **
      ** If scenario (a) caused the error then things are not so safe. The
      ** implicit assumption here is that if fstat() fails, things are in
      ** such bad shape that dropping a lock or two doesn't matter much.
      */
      close(h);
      h = -1;
    }
    unixLeaveMutex();
  }

#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
  else if( pLockingStyle == &afpIoMethods ){
    /* AFP locking uses the file path so it needs to be included in
    ** the afpLockingContext.

    ** included in the semLockingContext
    */
    unixEnterMutex();
    rc = findLockInfo(pNew, &pNew->pLock, &pNew->pOpen);
    if( (rc==SQLITE_OK) && (pNew->pOpen->pSem==NULL) ){
      char *zSemName = pNew->pOpen->aSemName;
      int n;
      sqlite3_snprintf(MAX_PATHNAME, zSemName, "/%s.sem",
                       pNew->pId->zCanonicalName);
      for( n=1; zSemName[n]; n++ )
        if( zSemName[n]=='/' ) zSemName[n] = '_';
      pNew->pOpen->pSem = sem_open(zSemName, O_CREAT, 0666, 1);
      if( pNew->pOpen->pSem == SEM_FAILED ){
        rc = SQLITE_NOMEM;
        pNew->pOpen->aSemName[0] = '\0';
      }
    }

    unlink(zFilename);
    isDelete = 0;
  }
  pNew->isDelete = isDelete;
#endif
  if( rc!=SQLITE_OK ){
    if( dirfd>=0 ) close(dirfd); /* silent leak if fail, already in error */
    if( h>=0 ) close(h);
  }else{
    pNew->pMethod = pLockingStyle;
    OpenCounter(+1);
  }
  return rc;
}

** Routine to transform a unixFile into a proxy-locking unixFile.
** Implementation in the proxy-lock division, but used by unixOpen()
** if SQLITE_PREFER_PROXY_LOCKING is defined.
*/
static int proxyTransformUnixFile(unixFile*, const char*);
#endif

/*
** Search for an unused file descriptor that was opened on the database 
** file (not a journal or master-journal file) identified by pathname
** zPath with SQLITE_OPEN_XXX flags matching those passed as the second
** argument to this function.
**
** Such a file descriptor may exist if a database connection was closed
** but the associated file descriptor could not be closed because some
** other file descriptor open on the same file is holding a file-lock.
** Refer to comments in the unixClose() function and the lengthy comment
** describing "Posix Advisory Locking" at the start of this file for 
** further details. Also, ticket #4018.
**
** If a suitable file descriptor is found, then it is returned. If no
** such file descriptor is located, -1 is returned.
*/
static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
  UnixUnusedFd *pUnused = 0;

  /* Do not search for an unused file descriptor on vxworks. Not because
  ** vxworks would not benefit from the change (it might, we're not sure),
  ** but because no way to test it is currently available. It is better 
  ** not to risk breaking vxworks support for the sake of such an obscure 
  ** feature.  */
#if !OS_VXWORKS
  struct stat sStat;                   /* Results of stat() call */

  /* A stat() call may fail for various reasons. If this happens, it is
  ** almost certain that an open() call on the same path will also fail.
  ** For this reason, if an error occurs in the stat() call here, it is
  ** ignored and -1 is returned. The caller will try to open a new file
  ** descriptor on the same path, fail, and return an error to SQLite.
  **
  ** Even if a subsequent open() call does succeed, the consequences of
  ** not searching for a resusable file descriptor are not dire.  */
  if( 0==stat(zPath, &sStat) ){
    struct unixOpenCnt *pO;
    struct unixFileId id;
    id.dev = sStat.st_dev;
    id.ino = sStat.st_ino;

    unixEnterMutex();
    for(pO=openList; pO && memcmp(&id, &pO->fileId, sizeof(id)); pO=pO->pNext);
    if( pO ){
      UnixUnusedFd **pp;
      for(pp=&pO->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
      pUnused = *pp;
      if( pUnused ){
        *pp = pUnused->pNext;
      }
    }
    unixLeaveMutex();
  }
#endif    /* if !OS_VXWORKS */
  return pUnused;
}

/*
** Open the file zPath.
** 
** Previously, the SQLite OS layer used three functions in place of this
** one:
**

static int unixOpen(
  sqlite3_vfs *pVfs,           /* The VFS for which this is the xOpen method */
  const char *zPath,           /* Pathname of file to be opened */
  sqlite3_file *pFile,         /* The file descriptor to be filled in */
  int flags,                   /* Input flags to control the opening */
  int *pOutFlags               /* Output flags returned to SQLite core */
){
  unixFile *p = (unixFile *)pFile;
  int fd = -1;                   /* File descriptor returned by open() */
  int dirfd = -1;                /* Directory file descriptor */
  int openFlags = 0;             /* Flags to pass to open() */
  int eType = flags&0xFFFFFF00;  /* Type of file to open */
  int noLock;                    /* True to omit locking primitives */
  int rc = SQLITE_OK;            /* Function Return Code */

  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
  int isCreate     = (flags & SQLITE_OPEN_CREATE);
  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);

  */
  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
  assert(isCreate==0 || isReadWrite);
  assert(isExclusive==0 || isCreate);
  assert(isDelete==0 || isCreate);

  /* The main DB, main journal, and master journal are never automatically
  ** deleted. Nor are they ever temporary files.  */

  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );

  /* Assert that the upper layer has set one of the "file-type" flags. */
  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
       || eType==SQLITE_OPEN_TRANSIENT_DB
  );

  memset(p, 0, sizeof(unixFile));

  if( eType==SQLITE_OPEN_MAIN_DB ){
    UnixUnusedFd *pUnused;
    pUnused = findReusableFd(zName, flags);
    if( pUnused ){
      fd = pUnused->fd;
    }else{
      pUnused = sqlite3_malloc(sizeof(*pUnused));
      if( !pUnused ){
        return SQLITE_NOMEM;
      }
    }
    p->pUnused = pUnused;
  }else if( !zName ){
    /* If zName is NULL, the upper layer is requesting a temp file. */
    assert(isDelete && !isOpenDirectory);
    rc = getTempname(MAX_PATHNAME+1, zTmpname);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    zName = zTmpname;
  }

  /* Determine the value of the flags parameter passed to POSIX function
  ** open(). These must be calculated even if open() is not called, as
  ** they may be stored as part of the file handle and used by the 
  ** 'conch file' locking functions later on.  */
  if( isReadonly )  openFlags |= O_RDONLY;
  if( isReadWrite ) openFlags |= O_RDWR;
  if( isCreate )    openFlags |= O_CREAT;
  if( isExclusive ) openFlags |= (O_EXCL|O_NOFOLLOW);
  openFlags |= (O_LARGEFILE|O_BINARY);

  if( fd<0 ){
    mode_t openMode = (isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
    fd = open(zName, openFlags, openMode);
    OSTRACE4("OPENX   %-3d %s 0%o\n", fd, zName, openFlags);
    if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
      /* Failed to open the file for read/write access. Try read-only. */
      flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
      openFlags &= ~(O_RDWR|O_CREAT);
      flags |= SQLITE_OPEN_READONLY;
      openFlags |= O_RDONLY;
      fd = open(zName, openFlags, openMode);
    }
    if( fd<0 ){
      rc = SQLITE_CANTOPEN;
      goto open_finished;
    }
  }
  assert( fd>=0 );
  if( pOutFlags ){
    *pOutFlags = flags;
  }

  if( p->pUnused ){
    p->pUnused->fd = fd;
    p->pUnused->flags = flags;
  }

  if( isDelete ){
#if OS_VXWORKS
    zPath = zName;
#else
    unlink(zName);
#endif
  }
#if SQLITE_ENABLE_LOCKING_STYLE
  else{
    p->openFlags = openFlags;









  }
#endif


  if( isOpenDirectory ){
    rc = openDirectory(zPath, &dirfd);
    if( rc!=SQLITE_OK ){
      /* It is safe to close fd at this point, because it is guaranteed not
      ** to be open on a database file. If it were open on a database file,
      ** it would not be safe to close as this would release any locks held
      ** on the file by this process.  */
      assert( eType!=SQLITE_OPEN_MAIN_DB );
      close(fd);             /* silently leak if fail, already in error */

      goto open_finished;
    }
  }

#ifdef FD_CLOEXEC
  fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
#endif

  noLock = eType!=SQLITE_OPEN_MAIN_DB;

#if SQLITE_PREFER_PROXY_LOCKING
  if( zPath!=NULL && !noLock && pVfs->xOpen ){
    char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
    int useProxy = 0;

    /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means 
    ** never use proxy, NULL means use proxy for non-local files only.  */

    if( envforce!=NULL ){
      useProxy = atoi(envforce)>0;
    }else{
      struct statfs fsInfo;

      if( statfs(zPath, &fsInfo) == -1 ){
        /* In theory, the close(fd) call is sub-optimal. If the file opened
        ** with fd is a database file, and there are other connections open
        ** on that file that are currently holding advisory locks on it,
        ** then the call to close() will cancel those locks. In practice,
        ** we're assuming that statfs() doesn't fail very often. At least
        ** not while other file descriptors opened by the same process on
        ** the same file are working.  */
        p->lastErrno = errno;
        if( dirfd>=0 ){
          close(dirfd); /* silently leak if fail, in error */
        }
        close(fd); /* silently leak if fail, in error */
        rc = SQLITE_IOERR_ACCESS;
        goto open_finished;
      }
      useProxy = !(fsInfo.f_flags&MNT_LOCAL);
    }
    if( useProxy ){
      rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
      if( rc==SQLITE_OK ){
        rc = proxyTransformUnixFile((unixFile*)pFile, ":auto:");
      }
      goto open_finished;
    }
  }
#endif
  
  rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
open_finished:
  if( rc!=SQLITE_OK ){
    sqlite3_free(p->pUnused);
  }
  return rc;
}


/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/
static int unixDelete(
  sqlite3_vfs *NotUsed,     /* VFS containing this as the xDelete method */

** Create a new VFS file descriptor (stored in memory obtained from
** sqlite3_malloc) and open the file named "path" in the file descriptor.
**
** The caller is responsible not only for closing the file descriptor
** but also for freeing the memory associated with the file descriptor.
*/
static int proxyCreateUnixFile(const char *path, unixFile **ppFile) {


  unixFile *pNew;
  int flags = SQLITE_OPEN_MAIN_DB|SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE;
  int rc = SQLITE_OK;
  sqlite3_vfs dummyVfs;






  pNew = (unixFile *)sqlite3_malloc(sizeof(unixFile));
  if( !pNew ){
    return SQLITE_NOMEM;

  }
  memset(pNew, 0, sizeof(unixFile));

  /* Call unixOpen() to open the proxy file. The flags passed to unixOpen()
  ** suggest that the file being opened is a "main database". This is
  ** necessary as other file types do not necessarily support locking. It
  ** is better to use unixOpen() instead of opening the file directly with
  ** open(), as unixOpen() sets up the various mechanisms required to
  ** make sure a call to close() does not cause the system to discard
  ** POSIX locks prematurely.
  **
  ** It is important that the xOpen member of the VFS object passed to 
  ** unixOpen() is NULL. This tells unixOpen() may try to open a proxy-file 
  ** for the proxy-file (creating a potential infinite loop).
  */
  dummyVfs.pAppData = (void*)&autolockIoFinder;
  dummyVfs.xOpen = 0;
  rc = unixOpen(&dummyVfs, path, (sqlite3_file *)pNew, flags, &flags);
  if( rc==SQLITE_OK && (flags&SQLITE_OPEN_READONLY) ){
    pNew->pMethod->xClose((sqlite3_file *)pNew);
    rc = SQLITE_CANTOPEN;
  }


  if( rc!=SQLITE_OK ){
    sqlite3_free(pNew);
    pNew = 0;
  }

  *ppFile = pNew;
  return rc;
}

/* takes the conch by taking a shared lock and read the contents conch, if 
** lockPath is non-NULL, the host ID and lock file path must match.  A NULL 
** lockPath means that the lockPath in the conch file will be used if the 
** host IDs match, or a new lock path will be generated automatically 

#if SQLITE_ENABLE_LOCKING_STYLE && (OS_VXWORKS || defined(__APPLE__))
    UNIXVFS("unix",          autolockIoFinder ),
#else
    UNIXVFS("unix",          posixIoFinder ),
#endif
    UNIXVFS("unix-none",     nolockIoFinder ),
    UNIXVFS("unix-dotfile",  dotlockIoFinder ),
    UNIXVFS("unix-wfl",      posixWflIoFinder ),
#if OS_VXWORKS
    UNIXVFS("unix-namedsem", semIoFinder ),
#endif
#if SQLITE_ENABLE_LOCKING_STYLE
    UNIXVFS("unix-posix",    posixIoFinder ),
#if !OS_VXWORKS
    UNIXVFS("unix-flock",    flockIoFinder ),

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to windows.


*/
#if SQLITE_OS_WIN               /* This file is used for windows only */


/*
** A Note About Memory Allocation:
**

{
  static struct tm y;
  FILETIME uTm, lTm;
  SYSTEMTIME pTm;
  sqlite3_int64 t64;
  t64 = *t;
  t64 = (t64 + 11644473600)*10000000;
  uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
  uTm.dwHighDateTime= (DWORD)(t64 >> 32);
  FileTimeToLocalFileTime(&uTm,&lTm);
  FileTimeToSystemTime(&lTm,&pTm);
  y.tm_year = pTm.wYear - 1900;
  y.tm_mon = pTm.wMonth - 1;
  y.tm_wday = pTm.wDayOfWeek;
  y.tm_mday = pTm.wDay;
  y.tm_hour = pTm.wHour;
  y.tm_min = pTm.wMinute;
  y.tm_sec = pTm.wSecond;
  return &y;
}

/* This will never be called, but defined to make the code compile */
#define GetTempPathA(a,b)

#define LockFile(a,b,c,d,e)       winceLockFile(&a, b, c, d, e)
#define UnlockFile(a,b,c,d,e)     winceUnlockFile(&a, b, c, d, e)
#define LockFileEx(a,b,c,d,e,f)   winceLockFileEx(&a, b, c, d, e, f)

#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]

/*
** Acquire a lock on the handle h
*/
static void winceMutexAcquire(HANDLE h){
   DWORD dwErr;
   do {

  DWORD dwFileOffsetHigh,
  DWORD nNumberOfBytesToLockLow,
  DWORD nNumberOfBytesToLockHigh
){
  winFile *pFile = HANDLE_TO_WINFILE(phFile);
  BOOL bReturn = FALSE;

  UNUSED_PARAMETER(dwFileOffsetHigh);
  UNUSED_PARAMETER(nNumberOfBytesToLockHigh);

  if (!pFile->hMutex) return TRUE;
  winceMutexAcquire(pFile->hMutex);

  /* Wanting an exclusive lock? */
  if (dwFileOffsetLow == SHARED_FIRST
       && nNumberOfBytesToLockLow == SHARED_SIZE){
    if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){

  DWORD dwFileOffsetHigh,
  DWORD nNumberOfBytesToUnlockLow,
  DWORD nNumberOfBytesToUnlockHigh
){
  winFile *pFile = HANDLE_TO_WINFILE(phFile);
  BOOL bReturn = FALSE;

  UNUSED_PARAMETER(dwFileOffsetHigh);
  UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);

  if (!pFile->hMutex) return TRUE;
  winceMutexAcquire(pFile->hMutex);

  /* Releasing a reader lock or an exclusive lock */
  if (dwFileOffsetLow == SHARED_FIRST){

    /* Did we have an exclusive lock? */
    if (pFile->local.bExclusive){
      assert(nNumberOfBytesToUnlockLow == SHARED_SIZE);
      pFile->local.bExclusive = FALSE;
      pFile->shared->bExclusive = FALSE;
      bReturn = TRUE;
    }

    /* Did we just have a reader lock? */
    else if (pFile->local.nReaders){
      assert(nNumberOfBytesToUnlockLow == 1);
      pFile->local.nReaders --;
      if (pFile->local.nReaders == 0)
      {
        pFile->shared->nReaders --;
      }
      bReturn = TRUE;
    }

  HANDLE *phFile,
  DWORD dwFlags,
  DWORD dwReserved,
  DWORD nNumberOfBytesToLockLow,
  DWORD nNumberOfBytesToLockHigh,
  LPOVERLAPPED lpOverlapped
){
  UNUSED_PARAMETER(dwReserved);
  UNUSED_PARAMETER(nNumberOfBytesToLockHigh);

  /* If the caller wants a shared read lock, forward this call
  ** to winceLockFile */
  if (lpOverlapped->Offset == SHARED_FIRST &&
      dwFlags == 1 &&
      nNumberOfBytesToLockLow == SHARED_SIZE){
    return winceLockFile(phFile, SHARED_FIRST, 0, 1, 0);
  }

** file.
*/
static int getSectorSize(
    sqlite3_vfs *pVfs,
    const char *zRelative     /* UTF-8 file name */
){
  DWORD bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
  /* GetDiskFreeSpace is not supported under WINCE */
#if SQLITE_OS_WINCE
  UNUSED_PARAMETER(pVfs);
  UNUSED_PARAMETER(zRelative);
#else
  char zFullpath[MAX_PATH+1];
  int rc;
  DWORD dwRet = 0;
  DWORD dwDummy;

  /*
  ** We need to get the full path name of the file
  ** to get the drive letter to look up the sector
  ** size.
  */
  rc = winFullPathname(pVfs, zRelative, MAX_PATH, zFullpath);

          }
        }
        dwRet = GetDiskFreeSpaceW((WCHAR*)zConverted,
                                  &dwDummy,
                                  &bytesPerSector,
                                  &dwDummy,
                                  &dwDummy);

      }else{
        /* trim path to just drive reference */
        CHAR *p = (CHAR *)zConverted;
        for(;*p;p++){
          if( *p == '\\' ){
            *p = '\0';
            break;
          }
        }
        dwRet = GetDiskFreeSpaceA((CHAR*)zConverted,
                                  &dwDummy,
                                  &bytesPerSector,
                                  &dwDummy,
                                  &dwDummy);

      }
      free(zConverted);
    }
    if( !dwRet ){
      bytesPerSector = SQLITE_DEFAULT_SECTOR_SIZE;
    }
  }
#endif
  return (int) bytesPerSector; 
}

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.

    winDlSym,          /* xDlSym */
    winDlClose,        /* xDlClose */
    winRandomness,     /* xRandomness */
    winSleep,          /* xSleep */
    winCurrentTime,    /* xCurrentTime */
    winGetLastError    /* xGetLastError */
  };

  sqlite3_vfs_register(&winVfs, 1);
  return SQLITE_OK; 
}
SQLITE_API int sqlite3_os_end(void){ 
  return SQLITE_OK;
}

** start of a transaction, and is thus usually less than a few thousand,
** but can be as large as 2 billion for a really big database.
**
** @(#) $Id: bitvec.c,v 1.17 2009/07/25 17:33:26 drh Exp $
*/

/* Size of the Bitvec structure in bytes. */
#define BITVEC_SZ        (sizeof(void*)*128)  /* 512 on 32bit.  1024 on 64bit */

/* Round the union size down to the nearest pointer boundary, since that's how 
** it will be aligned within the Bitvec struct. */
#define BITVEC_USIZE     (((BITVEC_SZ-(3*sizeof(u32)))/sizeof(Bitvec*))*sizeof(Bitvec*))

/* Type of the array "element" for the bitmap representation. 
** Should be a power of 2, and ideally, evenly divide into BITVEC_USIZE. 

  }
  pcache1.isInit = 1;
  return SQLITE_OK;
}

/*
** Implementation of the sqlite3_pcache.xShutdown method.
** Note that the static mutex allocated in xInit does 
** not need to be freed.
*/
static void pcache1Shutdown(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  assert( pcache1.isInit!=0 );
  memset(&pcache1, 0, sizeof(pcache1));
}

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.629 2009/08/10 17:48:57 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO

/*
** Macros for troubleshooting.  Normally turned off
*/
#if 0

    if( (O=(char*)(P->xCodec(P->pCodec,D,N,X)))==0 ){ E; }
#else
# define CODEC1(P,D,N,X,E)   /* NO-OP */
# define CODEC2(P,D,N,X,E,O) O=(char*)D
#endif

/*
** The maximum allowed sector size. 64KiB. If the xSectorsize() method 
** returns a value larger than this, then MAX_SECTOR_SIZE is used instead.
** This could conceivably cause corruption following a power failure on
** such a system. This is currently an undocumented limit.
*/
#define MAX_SECTOR_SIZE 0x10000

/*
** An instance of the following structure is allocated for each active
** savepoint and statement transaction in the system. All such structures
** are stored in the Pager.aSavepoint[] array, which is allocated and
** resized using sqlite3Realloc().
**

  assert( isOpen(pPager->fd) || pPager->noSync );
  if( (pPager->noSync) || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
   || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
  ){
    memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
    put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
  }else{

    memset(zHeader, 0, sizeof(aJournalMagic)+4);
  }

  /* The random check-hash initialiser */ 
  sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
  put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
  /* The initial database size */
  put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbOrigSize);

    /* Compute the total free space on the page */
    pc = get2byte(&data[hdr+1]);
    nFree = data[hdr+7] + top;
    while( pc>0 ){
      u16 next, size;
      if( pc<iCellFirst || pc>iCellLast ){
        /* Start of free block is off the page */
        return SQLITE_CORRUPT_BKPT; 
      }
      next = get2byte(&data[pc]);
      size = get2byte(&data[pc+2]);
      if( (next>0 && next<=pc+size+3) || pc+size>usableSize ){
        /* Free blocks must be in ascending order. And the last byte of
	** the free-block must lie on the database page.  */
        return SQLITE_CORRUPT_BKPT; 
      }
      nFree = nFree + size;
      pc = next;
    }

    /* At this point, nFree contains the sum of the offset to the start

#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
  /*
  ** If this Btree is a candidate for shared cache, try to find an
  ** existing BtShared object that we can share with
  */
  if( isMemdb==0 && zFilename && zFilename[0] ){
    if( vfsFlags & SQLITE_OPEN_SHAREDCACHE ){
      int nFullPathname = pVfs->mxPathname+1;
      char *zFullPathname = sqlite3Malloc(nFullPathname);
      sqlite3_mutex *mutexShared;
      p->sharable = 1;
      if( !zFullPathname ){
        sqlite3_free(p);
        return SQLITE_NOMEM;

          nCell = (int)pCur->info.nKey;
          pCellKey = sqlite3Malloc( nCell );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM;
            goto moveto_finish;
          }
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = sqlite3VdbeRecordCompare(nCell, pCellKey, pIdxKey);
          sqlite3_free(pCellKey);

        }
      }
      if( c==0 ){
        if( pPage->intKey && !pPage->leaf ){
          lwr = idx;
          upr = lwr - 1;
          break;

** If the seekResult parameter is non-zero, then a successful call to
** MovetoUnpacked() to seek cursor pCur to (pKey, nKey) has already
** been performed. seekResult is the search result returned (a negative
** number if pCur points at an entry that is smaller than (pKey, nKey), or
** a positive value if pCur points at an etry that is larger than 
** (pKey, nKey)). 
**
** If the seekResult parameter is non-zero, then the caller guarantees that
** cursor pCur is pointing at the existing copy of a row that is to be
** overwritten.  If the seekResult parameter is 0, then cursor pCur may
** point to any entry or to no entry at all and so this function has to seek
** the cursor before the new key can be inserted.
*/
SQLITE_PRIVATE int sqlite3BtreeInsert(
  BtCursor *pCur,                /* Insert data into the table of this cursor */
  const void *pKey, i64 nKey,    /* The key of the new record */
  const void *pData, int nData,  /* The data of the new record */
  int nZero,                     /* Number of extra 0 bytes to append to data */
  int appendBias,                /* True if this is likely an append */
  int seekResult                 /* Result of prior MovetoUnpacked() call */
){
  int rc;
  int loc = seekResult;          /* -1: before desired location  +1: after */
  int szNew;
  int idx;
  MemPage *pPage;
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;
  unsigned char *oldCell;
  unsigned char *newCell = 0;

/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function
** does not free any Mem.zMalloc buffer.
*/
SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
  testcase( p->flags & MEM_Agg );
  testcase( p->flags & MEM_Dyn );
  testcase( p->flags & MEM_RowSet );
  testcase( p->flags & MEM_Frame );
  if( p->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame) ){
    if( p->flags&MEM_Agg ){
      sqlite3VdbeMemFinalize(p, p->u.pDef);
      assert( (p->flags & MEM_Agg)==0 );
      sqlite3VdbeMemRelease(p);
    }else if( p->flags&MEM_Dyn && p->xDel ){
      assert( (p->flags&MEM_RowSet)==0 );
      p->xDel((void *)p->z);
      p->xDel = 0;
    }else if( p->flags&MEM_RowSet ){
      sqlite3RowSetClear(p->u.pRowSet);
    }else if( p->flags&MEM_Frame ){
      sqlite3VdbeMemSetNull(p);
    }
  }
}

/*
** Release any memory held by the Mem. This may leave the Mem in an
** inconsistent state, for example with (Mem.z==0) and

  /* Only mark the value as an integer if
  **
  **    (1) the round-trip conversion real->int->real is a no-op, and
  **    (2) The integer is neither the largest nor the smallest
  **        possible integer (ticket #3922)
  **
  ** The second and third terms in the following conditional enforces
  ** the second condition under the assumption that addition overflow causes
  ** values to wrap around.  On x86 hardware, the third term is always
  ** true and could be omitted.  But we leave it in because other
  ** architectures might behave differently.
  */
  if( pMem->r==(double)pMem->u.i && pMem->u.i>SMALLEST_INT64
      && ALWAYS(pMem->u.i<LARGEST_INT64) ){
    pMem->flags |= MEM_Int;
  }
}

/*
** Convert pMem to type integer.  Invalidate any prior representations.
*/

  return SQLITE_OK;
}

/*
** Delete any previous value and set the value stored in *pMem to NULL.
*/
SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem *pMem){
  if( pMem->flags & MEM_Frame ){
    sqlite3VdbeFrameDelete(pMem->u.pFrame);
  }
  if( pMem->flags & MEM_RowSet ){
    sqlite3RowSetClear(pMem->u.pRowSet);
  }
  MemSetTypeFlag(pMem, MEM_Null);
  pMem->type = SQLITE_NULL;
}

  sqlite3_value *pVal = 0;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;
  if( op==TK_REGISTER ){
    op = pExpr->op2;
  }

  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
    pVal = sqlite3ValueNew(db);
    if( pVal==0 ) goto no_mem;
    if( ExprHasProperty(pExpr, EP_IntValue) ){
      sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue);
    }else{
      zVal = sqlite3DbStrDup(db, pExpr->u.zToken);
      if( zVal==0 ) goto no_mem;
      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
      if( op==TK_FLOAT ) pVal->type = SQLITE_FLOAT;
    }
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
    }
    if( enc!=SQLITE_UTF8 ){

  assert( p->magic==VDBE_MAGIC_INIT );
  assert( j>=0 && j<p->nLabel );
  if( p->aLabel ){
    p->aLabel[j] = p->nOp;
  }
}

#ifdef SQLITE_DEBUG

/*
** The following type and function are used to iterate through all opcodes
** in a Vdbe main program and each of the sub-programs (triggers) it may 
** invoke directly or indirectly. It should be used as follows:
**
**   Op *pOp;
**   VdbeOpIter sIter;
**
**   memset(&sIter, 0, sizeof(sIter));
**   sIter.v = v;                            // v is of type Vdbe* 
**   while( (pOp = opIterNext(&sIter)) ){
**     // Do something with pOp
**   }
**   sqlite3DbFree(v->db, sIter.apSub);
** 
*/
typedef struct VdbeOpIter VdbeOpIter;
struct VdbeOpIter {
  Vdbe *v;                   /* Vdbe to iterate through the opcodes of */
  SubProgram **apSub;        /* Array of subprograms */
  int nSub;                  /* Number of entries in apSub */
  int iAddr;                 /* Address of next instruction to return */
  int iSub;                  /* 0 = main program, 1 = first sub-program etc. */
};
static Op *opIterNext(VdbeOpIter *p){
  Vdbe *v = p->v;
  Op *pRet = 0;
  Op *aOp;
  int nOp;

  if( p->iSub<=p->nSub ){

    if( p->iSub==0 ){
      aOp = v->aOp;
      nOp = v->nOp;
    }else{
      aOp = p->apSub[p->iSub-1]->aOp;
      nOp = p->apSub[p->iSub-1]->nOp;
    }
    assert( p->iAddr<nOp );

    pRet = &aOp[p->iAddr];
    p->iAddr++;
    if( p->iAddr==nOp ){
      p->iSub++;
      p->iAddr = 0;
    }
  
    if( pRet->p4type==P4_SUBPROGRAM ){
      int nByte = (p->nSub+1)*sizeof(SubProgram*);
      int j;
      for(j=0; j<p->nSub; j++){
        if( p->apSub[j]==pRet->p4.pProgram ) break;
      }
      if( j==p->nSub ){
        p->apSub = sqlite3DbReallocOrFree(v->db, p->apSub, nByte);
        if( !p->apSub ){
          pRet = 0;
        }else{
          p->apSub[p->nSub++] = pRet->p4.pProgram;
        }
      }
    }
  }

  return pRet;
}

/*
** Return true if the program stored in the VM passed as an argument may
** throw an ABORT exception (causing the statement, but not transaction
** to be rolled back). This condition is true if the main program or any
** sub-programs contains any of the following:
**
**   *  OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
**   *  OP_HaltIfNull with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
**   *  OP_Destroy
**   *  OP_VUpdate
**   *  OP_VRename
**
** This function is only used as part of an assert() statement. 
*/
SQLITE_PRIVATE int sqlite3VdbeMayAbort(Vdbe *v){
  int mayAbort = 0;
  Op *pOp;
  VdbeOpIter sIter;
  memset(&sIter, 0, sizeof(sIter));
  sIter.v = v;

  while( (pOp = opIterNext(&sIter))!=0 ){
    int opcode = pOp->opcode;
    if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename 
     || ((opcode==OP_Halt || opcode==OP_HaltIfNull) 
      && (pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
    ){
      mayAbort = 1;
      break;
    }
  }

  sqlite3DbFree(v->db, sIter.apSub);
  return mayAbort;
}
#endif

/*
** Loop through the program looking for P2 values that are negative
** on jump instructions.  Each such value is a label.  Resolve the
** label by setting the P2 value to its correct non-zero value.
**
** This routine is called once after all opcodes have been inserted.
**
** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument 
** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by 
** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.













*/
static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
  int i;
  int nMaxArgs = *pMaxFuncArgs;
  Op *pOp;
  int *aLabel = p->aLabel;


  p->readOnly = 1;

  for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
    u8 opcode = pOp->opcode;

    if( opcode==OP_Function || opcode==OP_AggStep ){
      if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
#ifndef SQLITE_OMIT_VIRTUALTABLE
    }else if( opcode==OP_VUpdate ){
      if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
#endif










    }else if( opcode==OP_Transaction && pOp->p2!=0 ){
      p->readOnly = 0;
#ifndef SQLITE_OMIT_VIRTUALTABLE


    }else if( opcode==OP_VFilter ){
      int n;
      assert( p->nOp - i >= 3 );
      assert( pOp[-1].opcode==OP_Integer );
      n = pOp[-1].p1;
      if( n>nMaxArgs ) nMaxArgs = n;
#endif
    }

    if( sqlite3VdbeOpcodeHasProperty(opcode, OPFLG_JUMP) && pOp->p2<0 ){
      assert( -1-pOp->p2<p->nLabel );
      pOp->p2 = aLabel[-1-pOp->p2];
    }
  }
  sqlite3DbFree(p->db, p->aLabel);
  p->aLabel = 0;

  *pMaxFuncArgs = nMaxArgs;














}

/*
** Return the address of the next instruction to be inserted.
*/
SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe *p){
  assert( p->magic==VDBE_MAGIC_INIT );
  return p->nOp;
}

/*
** This function returns a pointer to the array of opcodes associated with
** the Vdbe passed as the first argument. It is the callers responsibility
** to arrange for the returned array to be eventually freed using the 
** vdbeFreeOpArray() function.
**
** Before returning, *pnOp is set to the number of entries in the returned
** array. Also, *pnMaxArg is set to the larger of its current value and 
** the number of entries in the Vdbe.apArg[] array required to execute the 
** returned program.
*/
SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe *p, int *pnOp, int *pnMaxArg){
  VdbeOp *aOp = p->aOp;
  assert( aOp && !p->db->mallocFailed );

  /* Check that sqlite3VdbeUsesBtree() was not called on this VM */
  assert( p->aMutex.nMutex==0 );

  resolveP2Values(p, pnMaxArg);
  *pnOp = p->nOp;
  p->aOp = 0;
  return aOp;
}

/*
** Add a whole list of operations to the operation stack.  Return the
** address of the first operation added.
*/
SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
  int addr;

        sqlite3ValueFree((sqlite3_value*)p4);
        break;
      }
      case P4_VTAB : {
        sqlite3VtabUnlock((VTable *)p4);
        break;
      }
      case P4_SUBPROGRAM : {
        sqlite3VdbeProgramDelete(db, (SubProgram *)p4, 1);
        break;
      }
    }
  }
}

/*
** Free the space allocated for aOp and any p4 values allocated for the
** opcodes contained within. If aOp is not NULL it is assumed to contain 
** nOp entries. 
*/
static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
  if( aOp ){
    Op *pOp;
    for(pOp=aOp; pOp<&aOp[nOp]; pOp++){
      freeP4(db, pOp->p4type, pOp->p4.p);
#ifdef SQLITE_DEBUG
      sqlite3DbFree(db, pOp->zComment);
#endif     
    }
  }
  sqlite3DbFree(db, aOp);
}

/*
** Decrement the ref-count on the SubProgram structure passed as the
** second argument. If the ref-count reaches zero, free the structure.
**
** The array of VDBE opcodes stored as SubProgram.aOp is freed if
** either the ref-count reaches zero or parameter freeop is non-zero.
**
** Since the array of opcodes pointed to by SubProgram.aOp may directly
** or indirectly contain a reference to the SubProgram structure itself.
** By passing a non-zero freeop parameter, the caller may ensure that all
** SubProgram structures and their aOp arrays are freed, even when there
** are such circular references.
*/
SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *db, SubProgram *p, int freeop){
  if( p ){
    assert( p->nRef>0 );
    if( freeop || p->nRef==1 ){
      Op *aOp = p->aOp;
      p->aOp = 0;
      vdbeFreeOpArray(db, aOp, p->nOp);
      p->nOp = 0;
    }
    p->nRef--;
    if( p->nRef==0 ){
      sqlite3DbFree(db, p);
    }
  }
}


/*
** Change N opcodes starting at addr to No-ops.

** Change the comment on the the most recently coded instruction.  Or
** insert a No-op and add the comment to that new instruction.  This
** makes the code easier to read during debugging.  None of this happens
** in a production build.
*/
SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
  va_list ap;
  if( !p ) return;
  assert( p->nOp>0 || p->aOp==0 );
  assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
  if( p->nOp ){
    char **pz = &p->aOp[p->nOp-1].zComment;
    va_start(ap, zFormat);
    sqlite3DbFree(p->db, *pz);
    *pz = sqlite3VMPrintf(p->db, zFormat, ap);
    va_end(ap);
  }
}
SQLITE_PRIVATE void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){
  va_list ap;
  if( !p ) return;
  sqlite3VdbeAddOp0(p, OP_Noop);
  assert( p->nOp>0 || p->aOp==0 );
  assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
  if( p->nOp ){
    char **pz = &p->aOp[p->nOp-1].zComment;
    va_start(ap, zFormat);
    sqlite3DbFree(p->db, *pz);

      assert( (pMem->flags & MEM_Null)==0 );
      if( pMem->flags & MEM_Str ){
        zP4 = pMem->z;
      }else if( pMem->flags & MEM_Int ){
        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
      }else if( pMem->flags & MEM_Real ){
        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
      }else{
        assert( pMem->flags & MEM_Blob );
        zP4 = "(blob)";
      }
      break;
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
    case P4_VTAB: {
      sqlite3_vtab *pVtab = pOp->p4.pVtab->pVtab;
      sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
      break;
    }
#endif
    case P4_INTARRAY: {
      sqlite3_snprintf(nTemp, zTemp, "intarray");
      break;
    }
    case P4_SUBPROGRAM: {
      sqlite3_snprintf(nTemp, zTemp, "program");
      break;
    }
    default: {
      zP4 = pOp->p4.z;
      if( zP4==0 ){
        zP4 = zTemp;
        zTemp[0] = 0;
      }
    }
  }
  assert( zP4!=0 );
  return zP4;
}
#endif

/*
** Declare to the Vdbe that the BTree object at db->aDb[i] is used.

*/
SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe *p, int i){
  int mask;
  assert( i>=0 && i<p->db->nDb && i<sizeof(u32)*8 );
  assert( i<(int)sizeof(p->btreeMask)*8 );
  mask = ((u32)1)<<i;
  if( (p->btreeMask & mask)==0 ){

      ** callgrind, this causes a certain test case to hit the CPU 4.7 
      ** percent less (x86 linux, gcc version 4.1.2, -O6) than if 
      ** sqlite3MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
        sqlite3VdbeMemRelease(p);
      }else if( p->zMalloc ){
        sqlite3DbFree(db, p->zMalloc);
        p->zMalloc = 0;
      }

      p->flags = MEM_Null;
    }
    db->mallocFailed = malloc_failed;
  }
}

/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are
** allocated by the OP_Program opcode in sqlite3VdbeExec().
*/
SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame *p){
  int i;
  Mem *aMem = VdbeFrameMem(p);
  VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
  for(i=0; i<p->nChildCsr; i++){
    sqlite3VdbeFreeCursor(p->v, apCsr[i]);
  }
  releaseMemArray(aMem, p->nChildMem);
  sqlite3DbFree(p->v->db, p);
}


#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
SQLITE_PRIVATE int sqlite3VdbeReleaseBuffers(Vdbe *p){
  int ii;
  int nFree = 0;
  assert( sqlite3_mutex_held(p->db->mutex) );
  for(ii=1; ii<=p->nMem; ii++){