# define isatty(h) _isatty(h)
# ifndef access
#  define access(f,m) _access((f),(m))
# endif
# ifndef unlink
#  define unlink _unlink
# endif
# ifndef strdup
#  define strdup _strdup
# endif
# undef popen
# define popen _popen
# undef pclose
# define pclose _pclose
#else
 /* Make sure isatty() has a prototype. */
 extern int isatty(int);

*/
typedef struct ShellState ShellState;
struct ShellState {
  sqlite3 *db;           /* The database */
  u8 autoExplain;        /* Automatically turn on .explain mode */
  u8 autoEQP;            /* Run EXPLAIN QUERY PLAN prior to seach SQL stmt */
  u8 autoEQPtest;        /* autoEQP is in test mode */
  u8 autoEQPtrace;       /* autoEQP is in trace mode */
  u8 statsOn;            /* True to display memory stats before each finalize */
  u8 scanstatsOn;        /* True to display scan stats before each finalize */
  u8 openMode;           /* SHELL_OPEN_NORMAL, _APPENDVFS, or _ZIPFILE */
  u8 doXdgOpen;          /* Invoke start/open/xdg-open in output_reset() */
  u8 nEqpLevel;          /* Depth of the EQP output graph */
  u8 eTraceType;         /* SHELL_TRACE_* value for type of trace */
  unsigned mEqpLines;    /* Mask of veritical lines in the EQP output graph */

  int modePrior;         /* Saved mode */
  int cMode;             /* temporary output mode for the current query */
  int normalMode;        /* Output mode before ".explain on" */
  int writableSchema;    /* True if PRAGMA writable_schema=ON */
  int showHeader;        /* True to show column names in List or Column mode */
  int nCheck;            /* Number of ".check" commands run */
  unsigned shellFlgs;    /* Various flags */
  sqlite3_int64 szMax;   /* --maxsize argument to .open */
  char *zDestTable;      /* Name of destination table when MODE_Insert */
  char *zTempFile;       /* Temporary file that might need deleting */
  char zTestcase[30];    /* Name of current test case */
  char colSeparator[20]; /* Column separator character for several modes */
  char rowSeparator[20]; /* Row separator character for MODE_Ascii */
  char colSepPrior[20];  /* Saved column separator */
  char rowSepPrior[20];  /* Saved row separator */

  ".dbinfo ?DB?             Show status information about the database",
  ".dump ?TABLE? ...        Render all database content as SQL",
  "   Options:",
  "     --preserve-rowids      Include ROWID values in the output",
  "     --newlines             Allow unescaped newline characters in output",
  "   TABLE is LIKE pattern for the tables to dump",
  ".echo on|off             Turn command echo on or off",
  ".eqp on|off|full|...     Enable or disable automatic EXPLAIN QUERY PLAN",
  "   Other Modes:",
#ifdef SQLITE_DEBUG
  "      test                  Show raw EXPLAIN QUERY PLAN output",
  "      trace                 Like \"full\" but also enable \"PRAGMA vdbe_trace\"",
#endif
  "      trigger               Like \"full\" but also show trigger bytecode",
  ".excel                   Display the output of next command in a spreadsheet",
  ".exit ?CODE?             Exit this program with return-code CODE",
  ".expert                  EXPERIMENTAL. Suggest indexes for specified queries",
/* Because explain mode comes on automatically now, the ".explain" mode
** is removed from the help screen.  It is still supported for legacy, however */
/*".explain ?on|off|auto?   Turn EXPLAIN output mode on or off or to automatic",*/
  ".fullschema ?--indent?   Show schema and the content of sqlite_stat tables",

  "       -x    Open in a spreadsheet",
  ".open ?OPTIONS? ?FILE?   Close existing database and reopen FILE",
  "     Options:",
  "        --append        Use appendvfs to append database to the end of FILE",
#ifdef SQLITE_ENABLE_DESERIALIZE
  "        --deserialize   Load into memory useing sqlite3_deserialize()",
  "        --hexdb         Load the output of \"dbtotxt\" as an in-memory database",
  "        --maxsize N     Maximum size for --hexdb or --deserialized database",
#endif
  "        --new           Initialize FILE to an empty database",
  "        --readonly      Open FILE readonly",
  "        --zip           FILE is a ZIP archive",
  ".output ?FILE?           Send output to FILE or stdout if FILE is omitted",
  "     If FILE begins with '|' then open it as a pipe.",
  ".print STRING...         Print literal STRING",

      }
      rc = sqlite3_deserialize(p->db, "main", aData, nData, nData,
                   SQLITE_DESERIALIZE_RESIZEABLE |
                   SQLITE_DESERIALIZE_FREEONCLOSE);
      if( rc ){
        utf8_printf(stderr, "Error: sqlite3_deserialize() returns %d\n", rc);
      }
      if( p->szMax>0 ){
        sqlite3_file_control(p->db, "main", SQLITE_FCNTL_SIZE_LIMIT, &p->szMax);
      }
    }
#endif
  }
}

/*
** Attempt to close the databaes connection.  Report errors.

      rc = 1;
    }
  }else

  if( c=='e' && strncmp(azArg[0], "eqp", n)==0 ){
    if( nArg==2 ){
      p->autoEQPtest = 0;
      if( p->autoEQPtrace ){
        if( p->db ) sqlite3_exec(p->db, "PRAGMA vdbe_trace=OFF;", 0, 0, 0);
        p->autoEQPtrace = 0;
      }
      if( strcmp(azArg[1],"full")==0 ){
        p->autoEQP = AUTOEQP_full;
      }else if( strcmp(azArg[1],"trigger")==0 ){
        p->autoEQP = AUTOEQP_trigger;
#ifdef SQLITE_DEBUG
      }else if( strcmp(azArg[1],"test")==0 ){
        p->autoEQP = AUTOEQP_on;
        p->autoEQPtest = 1;
      }else if( strcmp(azArg[1],"trace")==0 ){
        p->autoEQP = AUTOEQP_full;
        p->autoEQPtrace = 1;
        open_db(p, 0);
        sqlite3_exec(p->db, "SELECT name FROM sqlite_master LIMIT 1", 0, 0, 0);
        sqlite3_exec(p->db, "PRAGMA vdbe_trace=ON;", 0, 0, 0);
#endif
      }else{
        p->autoEQP = (u8)booleanValue(azArg[1]);
      }
    }else{
      raw_printf(stderr, "Usage: .eqp off|on|trace|trigger|full\n");
      rc = 1;
    }
  }else

  if( c=='e' && strncmp(azArg[0], "exit", n)==0 ){
    if( nArg>1 && (rc = (int)integerValue(azArg[1]))!=0 ) exit(rc);
    rc = 2;

    session_close_all(p);
    close_db(p->db);
    p->db = 0;
    p->zDbFilename = 0;
    sqlite3_free(p->zFreeOnClose);
    p->zFreeOnClose = 0;
    p->openMode = SHELL_OPEN_UNSPEC;
    p->szMax = 0;
    /* Check for command-line arguments */
    for(iName=1; iName<nArg && azArg[iName][0]=='-'; iName++){
      const char *z = azArg[iName];
      if( optionMatch(z,"new") ){
        newFlag = 1;
#ifdef SQLITE_HAVE_ZLIB
      }else if( optionMatch(z, "zip") ){
        p->openMode = SHELL_OPEN_ZIPFILE;
#endif
      }else if( optionMatch(z, "append") ){
        p->openMode = SHELL_OPEN_APPENDVFS;
      }else if( optionMatch(z, "readonly") ){
        p->openMode = SHELL_OPEN_READONLY;
#ifdef SQLITE_ENABLE_DESERIALIZE
      }else if( optionMatch(z, "deserialize") ){
        p->openMode = SHELL_OPEN_DESERIALIZE;
      }else if( optionMatch(z, "hexdb") ){
        p->openMode = SHELL_OPEN_HEXDB;
      }else if( optionMatch(z, "maxsize") && iName+1<nArg ){
        p->szMax = integerValue(azArg[++iName]);
#endif /* SQLITE_ENABLE_DESERIALIZE */
      }else if( z[0]=='-' ){
        utf8_printf(stderr, "unknown option: %s\n", z);
        rc = 1;
        goto meta_command_exit;
      }
    }

  "   -append              append the database to the end of the file\n"
  "   -ascii               set output mode to 'ascii'\n"
  "   -bail                stop after hitting an error\n"
  "   -batch               force batch I/O\n"
  "   -column              set output mode to 'column'\n"
  "   -cmd COMMAND         run \"COMMAND\" before reading stdin\n"
  "   -csv                 set output mode to 'csv'\n"
#if defined(SQLITE_ENABLE_DESERIALIZE)
  "   -deserialize         open the database using sqlite3_deserialize()\n"
#endif
  "   -echo                print commands before execution\n"
  "   -init FILENAME       read/process named file\n"
  "   -[no]header          turn headers on or off\n"
#if defined(SQLITE_ENABLE_MEMSYS3) || defined(SQLITE_ENABLE_MEMSYS5)
  "   -heap SIZE           Size of heap for memsys3 or memsys5\n"
#endif
  "   -help                show this message\n"
  "   -html                set output mode to HTML\n"
  "   -interactive         force interactive I/O\n"
  "   -line                set output mode to 'line'\n"
  "   -list                set output mode to 'list'\n"
  "   -lookaside SIZE N    use N entries of SZ bytes for lookaside memory\n"
#if defined(SQLITE_ENABLE_DESERIALIZE)
  "   -maxsize N           maximum size for a --deserialize database\n"
#endif
  "   -mmap N              default mmap size set to N\n"
#ifdef SQLITE_ENABLE_MULTIPLEX
  "   -multiplex           enable the multiplexor VFS\n"
#endif
  "   -newline SEP         set output row separator. Default: '\\n'\n"
  "   -nullvalue TEXT      set text string for NULL values. Default ''\n"
  "   -pagecache SIZE N    use N slots of SZ bytes each for page cache memory\n"

      data.openMode = SHELL_OPEN_ZIPFILE;
#endif
    }else if( strcmp(z,"-append")==0 ){
      data.openMode = SHELL_OPEN_APPENDVFS;
#ifdef SQLITE_ENABLE_DESERIALIZE
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB)
    }else if( strncmp(z, "-A",2)==0 ){
      /* All remaining command-line arguments are passed to the ".archive"
      ** command, so ignore them */

      data.openMode = SHELL_OPEN_ZIPFILE;
#endif
    }else if( strcmp(z,"-append")==0 ){
      data.openMode = SHELL_OPEN_APPENDVFS;
#ifdef SQLITE_ENABLE_DESERIALIZE
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
    }else if( strcmp(z,"-ascii")==0 ){
      data.mode = MODE_Ascii;
      sqlite3_snprintf(sizeof(data.colSeparator), data.colSeparator,
                       SEP_Unit);

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.27.0"
#define SQLITE_VERSION_NUMBER 3027000
#define SQLITE_SOURCE_ID      "2019-01-27 02:45:32 9cf8ebd141aa2eb661d457624c76433bd9e4abfdef04aa52e28bc169172calt1"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
** layer a hint of how large the database file will grow to be during the
** current transaction.  This hint is not guaranteed to be accurate but it
** is often close.  The underlying VFS might choose to preallocate database
** file space based on this hint in order to help writes to the database
** file run faster.
**
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
** implements [sqlite3_deserialize()] to set an upper bound on the size
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
** If the integer pointed to is negative, then it is filled in with the
** current limit.  Otherwise the limit is set to the larger of the value
** of the integer pointed to and the current database size.  The integer
** pointed to is set to the new limit.
**
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
** extends and truncates the database file in chunks of a size specified
** by the user. The fourth argument to [sqlite3_file_control()] should 
** point to an integer (type int) containing the new chunk-size to use
** for the nominated database. Allocating database file space in large
** chunks (say 1MB at a time), may reduce file-system fragmentation and

#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
#define SQLITE_FCNTL_PDB                    30
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
#define SQLITE_FCNTL_DATA_VERSION           35
#define SQLITE_FCNTL_SIZE_LIMIT             36

/* deprecated names */
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO

**   Query for the details of phrase match iIdx within the current row.
**   Phrase matches are numbered starting from zero, so the iIdx argument
**   should be greater than or equal to zero and smaller than the value
**   output by xInstCount().
**
**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
**   to the column in which it occurs and *piOff the token offset of the




**   first token of the phrase. Returns SQLITE_OK if successful, or an error
**   code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. 
**
** xRowid:
**   Returns the rowid of the current row.
**

*/
#define ORIGVFS(p) ((sqlite3_vfs*)((p)->pAppData))

/* An open file */
struct MemFile {
  sqlite3_file base;              /* IO methods */
  sqlite3_int64 sz;               /* Size of the file */
  sqlite3_int64 szAlloc;          /* Space allocated to aData */
  sqlite3_int64 szMax;            /* Maximum allowed size of the file */
  unsigned char *aData;           /* content of the file */
  int nMmap;                      /* Number of memory mapped pages */
  unsigned mFlags;                /* Flags */
  int eLock;                      /* Most recent lock against this file */
};

/* The default maximum size of an in-memory database */
#ifndef SQLITE_MEMDB_DEFAULT_MAXSIZE
# define SQLITE_MEMDB_DEFAULT_MAXSIZE 1073741824
#endif

/*
** Methods for MemFile
*/
static int memdbClose(sqlite3_file*);
static int memdbRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int memdbWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);

** Try to enlarge the memory allocation to hold at least sz bytes
*/
static int memdbEnlarge(MemFile *p, sqlite3_int64 newSz){
  unsigned char *pNew;
  if( (p->mFlags & SQLITE_DESERIALIZE_RESIZEABLE)==0 || p->nMmap>0 ){
    return SQLITE_FULL;
  }
  if( newSz>p->szMax ){
    return SQLITE_FULL;
  }
  newSz *= 2;
  if( newSz>p->szMax ) newSz = p->szMax;
  pNew = sqlite3_realloc64(p->aData, newSz);
  if( pNew==0 ) return SQLITE_NOMEM;
  p->aData = pNew;
  p->szAlloc = newSz;
  return SQLITE_OK;
}

/*
** Write data to an memdb-file.
*/
static int memdbWrite(
  sqlite3_file *pFile,
  const void *z,
  int iAmt,
  sqlite_int64 iOfst
){
  MemFile *p = (MemFile *)pFile;
  if( NEVER(p->mFlags & SQLITE_DESERIALIZE_READONLY) ) return SQLITE_READONLY;
  if( iOfst+iAmt>p->sz ){
    int rc;
    if( iOfst+iAmt>p->szAlloc
     && (rc = memdbEnlarge(p, iOfst+iAmt))!=SQLITE_OK
    ){
      return rc;
    }
    if( iOfst>p->sz ) memset(p->aData+p->sz, 0, iOfst-p->sz);
    p->sz = iOfst+iAmt;
  }
  memcpy(p->aData+iOfst, z, iAmt);

}

/*
** Lock an memdb-file.
*/
static int memdbLock(sqlite3_file *pFile, int eLock){
  MemFile *p = (MemFile *)pFile;
  if( eLock>SQLITE_LOCK_SHARED 
   && (p->mFlags & SQLITE_DESERIALIZE_READONLY)!=0
  ){
    return SQLITE_READONLY;
  }
  p->eLock = eLock;
  return SQLITE_OK;
}

#if 0 /* Never used because memdbAccess() always returns false */
/*
** Check if another file-handle holds a RESERVED lock on an memdb-file.

*/
static int memdbFileControl(sqlite3_file *pFile, int op, void *pArg){
  MemFile *p = (MemFile *)pFile;
  int rc = SQLITE_NOTFOUND;
  if( op==SQLITE_FCNTL_VFSNAME ){
    *(char**)pArg = sqlite3_mprintf("memdb(%p,%lld)", p->aData, p->sz);
    rc = SQLITE_OK;
  }
  if( op==SQLITE_FCNTL_SIZE_LIMIT ){
    sqlite3_int64 iLimit = *(sqlite3_int64*)pArg;
    if( iLimit<p->sz ){
      if( iLimit<0 ){
        iLimit = p->szMax;
      }else{
        iLimit = p->sz;
      }
    }
    p->szMax = iLimit;
    *(sqlite3_int64*)pArg = iLimit;
    rc = SQLITE_OK;
  }
  return rc;
}

#if 0  /* Not used because of SQLITE_IOCAP_POWERSAFE_OVERWRITE */
/*
** Return the sector-size in bytes for an memdb-file.

static int memdbFetch(
  sqlite3_file *pFile,
  sqlite3_int64 iOfst,
  int iAmt,
  void **pp
){
  MemFile *p = (MemFile *)pFile;
  if( iOfst+iAmt>p->sz ){
    assert( CORRUPT_DB );
    *pp = 0;
  }else{
    p->nMmap++;
    *pp = (void*)(p->aData + iOfst);
  }
  return SQLITE_OK;
}

/* Release a memory-mapped page */
static int memdbUnfetch(sqlite3_file *pFile, sqlite3_int64 iOfst, void *pPage){
  MemFile *p = (MemFile *)pFile;
  p->nMmap--;

    return ORIGVFS(pVfs)->xOpen(ORIGVFS(pVfs), zName, pFile, flags, pOutFlags);
  }
  memset(p, 0, sizeof(*p));
  p->mFlags = SQLITE_DESERIALIZE_RESIZEABLE | SQLITE_DESERIALIZE_FREEONCLOSE;
  assert( pOutFlags!=0 );  /* True because flags==SQLITE_OPEN_MAIN_DB */
  *pOutFlags = flags | SQLITE_OPEN_MEMORY;
  p->base.pMethods = &memdb_io_methods;
  p->szMax = SQLITE_MEMDB_DEFAULT_MAXSIZE;
  return SQLITE_OK;
}

#if 0 /* Only used to delete rollback journals, master journals, and WAL
      ** files, none of which exist in memdb.  So this routine is never used */
/*
** Delete the file located at zPath. If the dirSync argument is true,

  }
  p = memdbFromDbSchema(db, zSchema);
  if( p==0 ){
    rc = SQLITE_ERROR;
  }else{
    p->aData = pData;
    p->sz = szDb;
    p->szAlloc = szBuf;
    p->szMax = szBuf;
    if( p->szMax<SQLITE_MEMDB_DEFAULT_MAXSIZE ){
      p->szMax = SQLITE_MEMDB_DEFAULT_MAXSIZE;
    }
    p->mFlags = mFlags;
    rc = SQLITE_OK;
  }

end_deserialize:
  sqlite3_finalize(pStmt);
  sqlite3_mutex_leave(db->mutex);

  int bias,           /* Bias search to the high end */
  int *pRes           /* Write search results here */
){
  int rc;                    /* Status code */
  UnpackedRecord *pIdxKey;   /* Unpacked index key */

  if( pKey ){
    KeyInfo *pKeyInfo = pCur->pKeyInfo;
    assert( nKey==(i64)(int)nKey );
    pIdxKey = sqlite3VdbeAllocUnpackedRecord(pKeyInfo);
    if( pIdxKey==0 ) return SQLITE_NOMEM_BKPT;
    sqlite3VdbeRecordUnpack(pKeyInfo, (int)nKey, pKey, pIdxKey);
    if( pIdxKey->nField==0 || pIdxKey->nField>pKeyInfo->nAllField ){
      rc = SQLITE_CORRUPT_BKPT;
      goto moveto_done;
    }
  }else{
    pIdxKey = 0;
  }
  rc = sqlite3BtreeMovetoUnpacked(pCur, pIdxKey, nKey, bias, pRes);

          u8 * const pCellBody = pCell - pPage->childPtrSize;
          pPage->xParseCell(pPage, pCellBody, &pCur->info);
          nCell = (int)pCur->info.nKey;
          testcase( nCell<0 );   /* True if key size is 2^32 or more */
          testcase( nCell==0 );  /* Invalid key size:  0x80 0x80 0x00 */
          testcase( nCell==1 );  /* Invalid key size:  0x80 0x80 0x01 */
          testcase( nCell==2 );  /* Minimum legal index key size */
          if( nCell<2 || nCell/pCur->pBt->usableSize>pCur->pBt->nPage ){
            rc = SQLITE_CORRUPT_PAGE(pPage);
            goto moveto_finish;
          }
          pCellKey = sqlite3Malloc( nCell+18 );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM_BKPT;
            goto moveto_finish;

    if( rc!=SQLITE_OK ){
      releasePage(*ppPage);
      *ppPage = 0;
    }
    TRACE(("ALLOCATE: %d from end of file\n", *pPgno));
  }

  assert( CORRUPT_DB || *pPgno!=PENDING_BYTE_PAGE(pBt) );

end_allocate_page:
  releasePage(pTrunk);
  releasePage(pPrevTrunk);
  assert( rc!=SQLITE_OK || sqlite3PagerPageRefcount((*ppPage)->pDbPage)<=1 );
  assert( rc!=SQLITE_OK || (*ppPage)->isInit==0 );
  return rc;

      */
      ptrmapPutOvflPtr(pPage, pPage, pCell, pRC);
    }
#endif
  }
}

/*
** The following parameters determine how many adjacent pages get involved
** in a balancing operation.  NN is the number of neighbors on either side
** of the page that participate in the balancing operation.  NB is the
** total number of pages that participate, including the target page and
** NN neighbors on either side.
**
** The minimum value of NN is 1 (of course).  Increasing NN above 1
** (to 2 or 3) gives a modest improvement in SELECT and DELETE performance
** in exchange for a larger degradation in INSERT and UPDATE performance.
** The value of NN appears to give the best results overall.
**
** (Later:) The description above makes it seem as if these values are
** tunable - as if you could change them and recompile and it would all work.
** But that is unlikely.  NB has been 3 since the inception of SQLite and
** we have never tested any other value.
*/
#define NN 1             /* Number of neighbors on either side of pPage */
#define NB 3             /* (NN*2+1): Total pages involved in the balance */

/*
** A CellArray object contains a cache of pointers and sizes for a
** consecutive sequence of cells that might be held on multiple pages.
**
** The cells in this array are the divider cell or cells from the pParent
** page plus up to three child pages.  There are a total of nCell cells.
**
** pRef is a pointer to one of the pages that contributes cells.  This is
** used to access information such as MemPage.intKey and MemPage.pBt->pageSize
** which should be common to all pages that contribute cells to this array.
**
** apCell[] and szCell[] hold, respectively, pointers to the start of each
** cell and the size of each cell.  Some of the apCell[] pointers might refer
** to overflow cells.  In other words, some apCel[] pointers might not point
** to content area of the pages.
**
** A szCell[] of zero means the size of that cell has not yet been computed.
**
** The cells come from as many as four different pages:
**
**             -----------
**             | Parent  |
**             -----------
**            /     |     \
**           /      |      \
**  ---------   ---------   ---------
**  |Child-1|   |Child-2|   |Child-3|
**  ---------   ---------   ---------
**
** The order of cells is in the array is:
**
**       1.  All cells from Child-1 in order
**       2.  The first divider cell from Parent
**       3.  All cells from Child-2 in order
**       4.  The second divider cell from Parent
**       5.  All cells from Child-3 in order
**
** The apEnd[] array holds pointer to the end of page for Child-1, the
** Parent, Child-2, the Parent (again), and Child-3.  The ixNx[] array
** holds the number of cells contained in each of these 5 stages, and
** all stages to the left.  Hence:
**    ixNx[0] = Number of cells in Child-1.
**    ixNx[1] = Number of cells in Child-1 plus 1 for first divider.
**    ixNx[2] = Number of cells in Child-1 and Child-2 + 1 for 1st divider.
**    ixNx[3] = Number of cells in Child-1 and Child-2 + both divider cells
**    ixNx[4] = Total number of cells.
*/
typedef struct CellArray CellArray;
struct CellArray {
  int nCell;              /* Number of cells in apCell[] */
  MemPage *pRef;          /* Reference page */
  u8 **apCell;            /* All cells begin balanced */
  u16 *szCell;            /* Local size of all cells in apCell[] */
  u8 *apEnd[NB*2];        /* MemPage.aDataEnd values */
  int ixNx[NB*2];         /* Index of at which we move to the next apEnd[] */
};

/*
** Make sure the cell sizes at idx, idx+1, ..., idx+N-1 have been
** computed.
*/
static void populateCellCache(CellArray *p, int idx, int N){

** function works around problems caused by this by making a copy of any 
** such cells before overwriting the page data.
**
** The MemPage.nFree field is invalidated by this function. It is the 
** responsibility of the caller to set it correctly.
*/
static int rebuildPage(
  CellArray *pCArray,             /* Content to be added to page pPg */
  int iFirst,                     /* First cell in pCArray to use */
  int nCell,                      /* Final number of cells on page */

  MemPage *pPg                    /* The page to be reconstructed */
){
  const int hdr = pPg->hdrOffset;          /* Offset of header on pPg */
  u8 * const aData = pPg->aData;           /* Pointer to data for pPg */
  const int usableSize = pPg->pBt->usableSize;
  u8 * const pEnd = &aData[usableSize];
  int i = iFirst;                 /* Which cell to copy from pCArray*/
  int j;                          /* Start of cell content area */
  int iEnd = i+nCell;             /* Loop terminator */
  u8 *pCellptr = pPg->aCellIdx;
  u8 *pTmp = sqlite3PagerTempSpace(pPg->pBt->pPager);
  u8 *pData;
  int k;                          /* Current slot in pCArray->apEnd[] */
  u8 *pSrcEnd;                    /* Current pCArray->apEnd[k] value */

  assert( i<iEnd );
  j = get2byte(&aData[hdr+5]);
  memcpy(&pTmp[j], &aData[j], usableSize - j);

  for(k=0; pCArray->ixNx[k]<=i && ALWAYS(k<NB*2); k++){}
  pSrcEnd = pCArray->apEnd[k];

  pData = pEnd;

  while( 1/*exit by break*/ ){
    u8 *pCell = pCArray->apCell[i];
    u16 sz = pCArray->szCell[i];
    assert( sz>0 );
    if( SQLITE_WITHIN(pCell,aData,pEnd) ){
      if( ((uptr)(pCell+sz))>(uptr)pEnd ) return SQLITE_CORRUPT_BKPT;
      pCell = &pTmp[pCell - aData];
    }else if( (uptr)(pCell+sz)>(uptr)pSrcEnd
           && (uptr)(pCell)<(uptr)pSrcEnd
    ){
      return SQLITE_CORRUPT_BKPT;
    }

    pData -= sz;
    put2byte(pCellptr, (pData - aData));
    pCellptr += 2;
    if( pData < pCellptr ) return SQLITE_CORRUPT_BKPT;
    memcpy(pData, pCell, sz);
    assert( sz==pPg->xCellSize(pPg, pCell) || CORRUPT_DB );
    testcase( sz!=pPg->xCellSize(pPg,pCell) );
    i++;
    if( i>=iEnd ) break;
    if( pCArray->ixNx[k]<=i ){
      k++;
      pSrcEnd = pCArray->apEnd[k];
    }
  }

  /* The pPg->nFree field is now set incorrectly. The caller will fix it. */
  pPg->nCell = nCell;
  pPg->nOverflow = 0;

  put2byte(&aData[hdr+1], 0);
  put2byte(&aData[hdr+3], pPg->nCell);
  put2byte(&aData[hdr+5], pData - aData);
  aData[hdr+7] = 0x00;
  return SQLITE_OK;
}

/*
** The pCArray objects contains pointers to b-tree cells and the cell sizes.

** This function attempts to add the cells stored in the array to page pPg.
** If it cannot (because the page needs to be defragmented before the cells
** will fit), non-zero is returned. Otherwise, if the cells are added
** successfully, zero is returned.
**
** Argument pCellptr points to the first entry in the cell-pointer array
** (part of page pPg) to populate. After cell apCell[0] is written to the
** page body, a 16-bit offset is written to pCellptr. And so on, for each
** cell in the array. It is the responsibility of the caller to ensure
** that it is safe to overwrite this part of the cell-pointer array.
**

** all cells - not just those inserted by the current call). If the content
** area must be extended to before this point in order to accomodate all
** cells in apCell[], then the cells do not fit and non-zero is returned.
*/
static int pageInsertArray(
  MemPage *pPg,                   /* Page to add cells to */
  u8 *pBegin,                     /* End of cell-pointer array */
  u8 **ppData,                    /* IN/OUT: Page content-area pointer */
  u8 *pCellptr,                   /* Pointer to cell-pointer area */
  int iFirst,                     /* Index of first cell to add */
  int nCell,                      /* Number of cells to add to pPg */
  CellArray *pCArray              /* Array of cells */
){
  int i = iFirst;                 /* Loop counter - cell index to insert */
  u8 *aData = pPg->aData;         /* Complete page */
  u8 *pData = *ppData;            /* Content area.  A subset of aData[] */
  int iEnd = iFirst + nCell;      /* End of loop. One past last cell to ins */
  int k;                          /* Current slot in pCArray->apEnd[] */
  u8 *pEnd;                       /* Maximum extent of cell data */
  assert( CORRUPT_DB || pPg->hdrOffset==0 );    /* Never called on page 1 */
  if( iEnd<=iFirst ) return 0;
  for(k=0; pCArray->ixNx[k]<=i && ALWAYS(k<NB*2); k++){}
  pEnd = pCArray->apEnd[k];
  while( 1 /*Exit by break*/ ){
    int sz, rc;
    u8 *pSlot;
    sz = cachedCellSize(pCArray, i);
    if( (aData[1]==0 && aData[2]==0) || (pSlot = pageFindSlot(pPg,sz,&rc))==0 ){
      if( (pData - pBegin)<sz ) return 1;
      pData -= sz;
      pSlot = pData;
    }
    /* pSlot and pCArray->apCell[i] will never overlap on a well-formed
    ** database.  But they might for a corrupt database.  Hence use memmove()
    ** since memcpy() sends SIGABORT with overlapping buffers on OpenBSD */
    assert( (pSlot+sz)<=pCArray->apCell[i]
         || pSlot>=(pCArray->apCell[i]+sz)
         || CORRUPT_DB );
    if( (uptr)(pCArray->apCell[i]+sz)>(uptr)pEnd
     && (uptr)(pCArray->apCell[i])<(uptr)pEnd
    ){
      assert( CORRUPT_DB );
      (void)SQLITE_CORRUPT_BKPT;
      return 1;
    }
    memmove(pSlot, pCArray->apCell[i], sz);
    put2byte(pCellptr, (pSlot - aData));
    pCellptr += 2;
    i++;
    if( i>=iEnd ) break;
    if( pCArray->ixNx[k]<=i ){
      k++;
      pEnd = pCArray->apEnd[k];
    }
  }
  *ppData = pData;
  return 0;
}

/*
** The pCArray object contains pointers to b-tree cells and their sizes.
**
** This function adds the space associated with each cell in the array
** that is currently stored within the body of pPg to the pPg free-list.
** The cell-pointers and other fields of the page are not updated.
**
** This function returns the total number of cells added to the free-list.
*/
static int pageFreeArray(
  MemPage *pPg,                   /* Page to edit */
  int iFirst,                     /* First cell to delete */
  int nCell,                      /* Cells to delete */

    assert( pFree>aData && (pFree - aData)<65536 );
    freeSpace(pPg, (u16)(pFree - aData), szFree);
  }
  return nRet;
}

/*
** pCArray contains pointers to and sizes of all cells in the pages being
** balanced.  The current page, pPg, has pPg->nCell cells starting with
** pCArray->apCell[iOld].  After balancing, this page should hold nNew cells
** starting at apCell[iNew].
**
** This routine makes the necessary adjustments to pPg so that it contains
** the correct cells after being balanced.
**
** The pPg->nFree field is invalid when this function returns. It is the
** responsibility of the caller to set it correctly.

  }
#endif

  return SQLITE_OK;
 editpage_fail:
  /* Unable to edit this page. Rebuild it from scratch instead. */
  populateCellCache(pCArray, iNew, nNew);
  return rebuildPage(pCArray, iNew, nNew, pPg);
}

















#ifndef SQLITE_OMIT_QUICKBALANCE
/*
** This version of balance() handles the common special case where
** a new entry is being inserted on the extreme right-end of the
** tree, in other words, when the new entry will become the largest

  if( rc==SQLITE_OK ){

    u8 *pOut = &pSpace[4];
    u8 *pCell = pPage->apOvfl[0];
    u16 szCell = pPage->xCellSize(pPage, pCell);
    u8 *pStop;
    CellArray b;

    assert( sqlite3PagerIswriteable(pNew->pDbPage) );
    assert( CORRUPT_DB || pPage->aData[0]==(PTF_INTKEY|PTF_LEAFDATA|PTF_LEAF) );
    zeroPage(pNew, PTF_INTKEY|PTF_LEAFDATA|PTF_LEAF);
    b.nCell = 1;
    b.pRef = pPage;
    b.apCell = &pCell;
    b.szCell = &szCell;
    b.apEnd[0] = pPage->aDataEnd;
    b.ixNx[0] = 2;
    rc = rebuildPage(&b, 0, 1, pNew);
    if( NEVER(rc) ){
      releasePage(pNew);
      return rc;
    }
    pNew->nFree = pBt->usableSize - pNew->cellOffset - 2 - szCell;

    /* If this is an auto-vacuum database, update the pointer map
    ** with entries for the new page, and any pointer from the 
    ** cell on the page to an overflow page. If either of these
    ** operations fails, the return code is set, but the contents
    ** of the parent page are still manipulated by thh code below.

  **              the right of the i-th sibling page.
  ** usableSpace: Number of bytes of space available on each sibling.
  ** 
  */
  usableSpace = pBt->usableSize - 12 + leafCorrection;
  for(i=0; i<nOld; i++){
    MemPage *p = apOld[i];
    b.apEnd[i*2] = p->aDataEnd;
    b.apEnd[i*2+1] = pParent->aDataEnd;
    b.ixNx[i*2] = cntOld[i];
    b.ixNx[i*2+1] = cntOld[i]+1;
    szNew[i] = usableSpace - p->nFree;
    for(j=0; j<p->nOverflow; j++){
      szNew[i] += 2 + p->xCellSize(p, p->apOvfl[j]);
    }
    cntNew[i] = cntOld[i];
  }
  k = nOld;

                                 iAmt-nData);
      if( rc ) return rc;
      iAmt = nData;
    }
    if( memcmp(pDest, ((u8*)pX->pData) + iOffset, iAmt)!=0 ){
      int rc = sqlite3PagerWrite(pPage->pDbPage);
      if( rc ) return rc;
      /* In a corrupt database, it is possible for the source and destination
      ** buffers to overlap.  This is harmless since the database is already
      ** corrupt but it does cause valgrind and ASAN warnings.  So use
      ** memmove(). */
      memmove(pDest, ((u8*)pX->pData) + iOffset, iAmt);
    }
  }
  return SQLITE_OK;
}

/*
** Overwrite the cell that cursor pCur is pointing to with fresh content

  ** the cursor to the largest entry in the tree that is smaller than
  ** the entry being deleted. This cell will replace the cell being deleted
  ** from the internal node. The 'previous' entry is used for this instead
  ** of the 'next' entry, as the previous entry is always a part of the
  ** sub-tree headed by the child page of the cell being deleted. This makes
  ** balancing the tree following the delete operation easier.  */
  if( !pPage->leaf ){
    pCur->skipNext = 0;
    rc = sqlite3BtreePrevious(pCur, 0);
    assert( rc!=SQLITE_DONE );
    if( rc ) return rc;
  }

  /* Save the positions of any other cursors open on this table before
  ** making any modifications.  */

** and MEM_Blob values may be discarded, MEM_Int, MEM_Real, and MEM_Null
** values are preserved.
**
** Return SQLITE_OK on success or an error code (probably SQLITE_NOMEM)
** if unable to complete the resizing.
*/
SQLITE_PRIVATE int sqlite3VdbeMemClearAndResize(Mem *pMem, int szNew){
  assert( CORRUPT_DB || szNew>0 );
  assert( (pMem->flags & MEM_Dyn)==0 || pMem->szMalloc==0 );
  if( pMem->szMalloc<szNew ){
    return sqlite3VdbeMemGrow(pMem, szNew, 0);
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  pMem->z = pMem->zMalloc;
  pMem->flags &= (MEM_Null|MEM_Int|MEM_Real);

#endif
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  else if( op==TK_FUNCTION && pCtx!=0 ){
    rc = valueFromFunction(db, pExpr, enc, affinity, &pVal, pCtx);
  }
#endif
  else if( op==TK_TRUEFALSE ){
    pVal = valueNew(db, pCtx);
    if( pVal ){
      pVal->flags = MEM_Int;
      pVal->u.i = pExpr->u.zToken[4]==0;
    }
  }

  *ppVal = pVal;
  return rc;

no_mem:
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4

  sIter.v = v;

  while( (pOp = opIterNext(&sIter))!=0 ){
    int opcode = pOp->opcode;
    if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename 
     || opcode==OP_VDestroy
     || ((opcode==OP_Halt || opcode==OP_HaltIfNull) 
      && ((pOp->p1)!=SQLITE_OK && pOp->p2==OE_Abort))
    ){
      hasAbort = 1;
      break;
    }
    if( opcode==OP_CreateBtree && pOp->p3==BTREE_INTKEY ) hasCreateTable = 1;
    if( opcode==OP_InitCoroutine ) hasInitCoroutine = 1;
#ifndef SQLITE_OMIT_FOREIGN_KEY

SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(
  KeyInfo *pKeyInfo,     /* Information about the record format */
  int nKey,              /* Size of the binary record */
  const void *pKey,      /* The binary record */
  UnpackedRecord *p      /* Populate this structure before returning. */
){
  const unsigned char *aKey = (const unsigned char *)pKey;
  u32 d; 
  u32 idx;                        /* Offset in aKey[] to read from */
  u16 u;                          /* Unsigned loop counter */
  u32 szHdr;
  Mem *pMem = p->aMem;

  p->default_rc = 0;
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  idx = getVarint32(aKey, szHdr);
  d = szHdr;
  u = 0;
  while( idx<szHdr && d<=(u32)nKey ){
    u32 serial_type;

    idx += getVarint32(&aKey[idx], serial_type);
    pMem->enc = pKeyInfo->enc;
    pMem->db = pKeyInfo->db;
    /* pMem->flags = 0; // sqlite3VdbeSerialGet() will set this for us */
    pMem->szMalloc = 0;
    pMem->z = 0;
    d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
    pMem++;
    if( (++u)>=p->nField ) break;
  }
  if( d>(u32)nKey && u ){
    assert( CORRUPT_DB );
    /* In a corrupt record entry, the last pMem might have been set up using 
    ** uninitialized memory. Overwrite its value with NULL, to prevent
    ** warnings from MSAN. */
    sqlite3VdbeMemSetNull(pMem-1);
  }
  assert( u<=pKeyInfo->nKeyField + 1 );

    /* Extract the values to be compared.
    */
    d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);

    /* Do the comparison
    */
    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
                           pKeyInfo->nAllField>i ? pKeyInfo->aColl[i] : 0);
    if( rc!=0 ){
      assert( mem1.szMalloc==0 );  /* See comment below */
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;  /* Invert the result for DESC sort order. */
      }
      goto debugCompareEnd;
    }

        rc = -1;
      }else if( !(serial_type & 0x01) ){
        rc = +1;
      }else{
        mem1.n = (serial_type - 12) / 2;
        testcase( (d1+mem1.n)==(unsigned)nKey1 );
        testcase( (d1+mem1.n+1)==(unsigned)nKey1 );
        if( (d1+mem1.n) > (unsigned)nKey1
         || (pKeyInfo = pPKey2->pKeyInfo)->nAllField<=i
        ){
          pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
          return 0;                /* Corruption */
        }else if( pKeyInfo->aColl[i] ){
          mem1.enc = pKeyInfo->enc;
          mem1.db = pKeyInfo->db;
          mem1.flags = MEM_Str;
          mem1.z = (char*)&aKey1[d1];
          rc = vdbeCompareMemString(
              &mem1, pRhs, pKeyInfo->aColl[i], &pPKey2->errCode
          );

** interpret as a string if we want to).  Compute its corresponding
** numeric type, if has one.  Set the pMem->u.r and pMem->u.i fields
** accordingly.
*/
static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
  assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
  assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
  ExpandBlob(pMem);
  if( sqlite3AtoF(pMem->z, &pMem->u.r, pMem->n, pMem->enc)==0 ){
    return 0;
  }
  if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==0 ){
    return MEM_Int;
  }
  return MEM_Real;

  p->apCsr = (VdbeCursor **)&aMem[p->nMem];
  pFrame->aOnce = (u8*)&p->apCsr[pProgram->nCsr];
  memset(pFrame->aOnce, 0, (pProgram->nOp + 7)/8);
  p->aOp = aOp = pProgram->aOp;
  p->nOp = pProgram->nOp;
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
  p->anExec = 0;
#endif
#ifdef SQLITE_DEBUG
  /* Verify that second and subsequent executions of the same trigger do not
  ** try to reuse register values from the first use. */
  {
    int i;
    for(i=0; i<p->nMem; i++){
      aMem[i].pScopyFrom = 0;  /* Prevent false-positive AboutToChange() errs */
      aMem[i].flags |= MEM_Undefined; /* Cause a fault if this reg is reused */
    }
  }
#endif
  pOp = &aOp[-1];

  break;
}

/* Opcode: Param P1 P2 * * *

** an SQL statement.
*/
/* #include "sqliteInt.h" */
/* #include <stdlib.h> */
/* #include <string.h> */


#if !defined(SQLITE_OMIT_WINDOWFUNC)
/*
** Walk all expressions linked into the list of Window objects passed
** as the second argument.
*/
static int walkWindowList(Walker *pWalker, Window *pList){
  Window *pWin;
  for(pWin=pList; pWin; pWin=pWin->pNextWin){
    if( sqlite3WalkExprList(pWalker, pWin->pOrderBy) ) return WRC_Abort;
    if( sqlite3WalkExprList(pWalker, pWin->pPartition) ) return WRC_Abort;
    if( sqlite3WalkExpr(pWalker, pWin->pFilter) ) return WRC_Abort;
  }
  return WRC_Continue;
}
#endif

/*
** Walk an expression tree.  Invoke the callback once for each node
** of the expression, while descending.  (In other words, the callback
** is invoked before visiting children.)
**
** The return value from the callback should be one of the WRC_*
** constants to specify how to proceed with the walk.

      }else if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
      }else if( pExpr->x.pList ){
        if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
      }
#ifndef SQLITE_OMIT_WINDOWFUNC
      if( ExprHasProperty(pExpr, EP_WinFunc) ){



        if( walkWindowList(pWalker, pExpr->y.pWin) ) return WRC_Abort;
      }
#endif
    }
    break;
  }
  return WRC_Continue;
}

SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker *pWalker, Select *p){
  if( sqlite3WalkExprList(pWalker, p->pEList) ) return WRC_Abort;
  if( sqlite3WalkExpr(pWalker, p->pWhere) ) return WRC_Abort;
  if( sqlite3WalkExprList(pWalker, p->pGroupBy) ) return WRC_Abort;
  if( sqlite3WalkExpr(pWalker, p->pHaving) ) return WRC_Abort;
  if( sqlite3WalkExprList(pWalker, p->pOrderBy) ) return WRC_Abort;
  if( sqlite3WalkExpr(pWalker, p->pLimit) ) return WRC_Abort;
#if !defined(SQLITE_OMIT_WINDOWFUNC) && !defined(SQLITE_OMIT_ALTERTABLE)
  {
    Parse *pParse = pWalker->pParse;
    if( pParse && IN_RENAME_OBJECT ){
      int rc = walkWindowList(pWalker, p->pWinDefn);
      assert( rc==WRC_Continue );
      return rc;
    }
  }
#endif
  return WRC_Continue;
}

/*
** Walk the parse trees associated with all subqueries in the
** FROM clause of SELECT statement p.  Do not invoke the select
** callback on p, but do invoke it on each FROM clause subquery

        }
      }
      sqlite3WalkExprList(pWalker, pList);
      if( is_agg ){
#ifndef SQLITE_OMIT_WINDOWFUNC
        if( pExpr->y.pWin ){
          Select *pSel = pNC->pWinSelect;
          sqlite3WindowUpdate(pParse, pSel->pWinDefn, pExpr->y.pWin, pDef);
          sqlite3WalkExprList(pWalker, pExpr->y.pWin->pPartition);
          sqlite3WalkExprList(pWalker, pExpr->y.pWin->pOrderBy);
          sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);

          if( 0==pSel->pWin 
           || 0==sqlite3WindowCompare(pParse, pSel->pWin, pExpr->y.pWin) 
          ){
            pExpr->y.pWin->pNextWin = pSel->pWin;
            pSel->pWin = pExpr->y.pWin;
          }
          pNC->ncFlags |= NC_AllowWin;

          }else{
            pDup = sqlite3ExprDup(db, pE, 0);
          }
          if( !db->mallocFailed ){
            assert(pDup);
            iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup);
          }
          if( !IN_RENAME_OBJECT ){





            sqlite3ExprDelete(db, pDup);
          }
        }
      }
      if( iCol>0 ){
        /* Convert the ORDER BY term into an integer column number iCol,
        ** taking care to preserve the COLLATE clause if it exists */
        if( !IN_RENAME_OBJECT ){
          Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0);
          if( pNew==0 ) return 1;
          pNew->flags |= EP_IntValue;
          pNew->u.iValue = iCol;
          if( pItem->pExpr==pE ){
            pItem->pExpr = pNew;
          }else{
            Expr *pParent = pItem->pExpr;
            assert( pParent->op==TK_COLLATE );
            while( pParent->pLeft->op==TK_COLLATE ) pParent = pParent->pLeft;
            assert( pParent->pLeft==pE );
            pParent->pLeft = pNew;
          }
          sqlite3ExprDelete(db, pE);
          pItem->u.x.iOrderByCol = (u16)iCol;
        }
        pItem->done = 1;
      }else{
        moreToDo = 1;
      }
    }
    pSelect = pSelect->pNext;
  }

        if( ExprHasProperty(pItem->pExpr, EP_Agg) ){
          sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
              "the GROUP BY clause");
          return WRC_Abort;
        }
      }
    }

    if( IN_RENAME_OBJECT ){
      Window *pWin;
      for(pWin=p->pWinDefn; pWin; pWin=pWin->pNextWin){
        if( sqlite3ResolveExprListNames(&sNC, pWin->pOrderBy)
         || sqlite3ResolveExprListNames(&sNC, pWin->pPartition)
        ){
          return WRC_Abort;
        }
      }
    }

    /* If this is part of a compound SELECT, check that it has the right
    ** number of expressions in the select list. */
    if( p->pNext && p->pEList->nExpr!=p->pNext->pEList->nExpr ){
      sqlite3SelectWrongNumTermsError(pParse, p->pNext);
      return WRC_Abort;
    }

SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
  Walker w;
  w.xExprCallback = analyzeAggregate;
  w.xSelectCallback = analyzeAggregatesInSelect;
  w.xSelectCallback2 = analyzeAggregatesInSelectEnd;
  w.walkerDepth = 0;
  w.u.pNC = pNC;
  w.pParse = 0;
  assert( pNC->pSrcList!=0 );
  sqlite3WalkExpr(&w, pExpr);
}

/*
** Call sqlite3ExprAnalyzeAggregates() for every expression in an
** expression list.  Return the number of errors.

 {/* zName:     */ "compile_options",
  /* ePragTyp:  */ PragTyp_COMPILE_OPTIONS,
  /* ePragFlg:  */ PragFlg_Result0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "count_changes",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_CountRows },
#endif
#endif
#if !defined(SQLITE_OMIT_PAGER_PRAGMAS) && SQLITE_OS_WIN
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "data_store_directory",
  /* ePragTyp:  */ PragTyp_DATA_STORE_DIRECTORY,
  /* ePragFlg:  */ PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
#endif
#if !defined(SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS)
 {/* zName:     */ "data_version",
  /* ePragTyp:  */ PragTyp_HEADER_VALUE,
  /* ePragFlg:  */ PragFlg_ReadOnly|PragFlg_Result0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ BTREE_DATA_VERSION },
#endif
#if !defined(SQLITE_OMIT_SCHEMA_PRAGMAS)
 {/* zName:     */ "database_list",
  /* ePragTyp:  */ PragTyp_DATABASE_LIST,
  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0,
  /* ColNames:  */ 35, 3,
  /* iArg:      */ 0 },
#endif
#if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "default_cache_size",
  /* ePragTyp:  */ PragTyp_DEFAULT_CACHE_SIZE,
  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1,
  /* ColNames:  */ 45, 1,
  /* iArg:      */ 0 },
#endif
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
 {/* zName:     */ "defer_foreign_keys",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_DeferFKs },
#endif
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "empty_result_callbacks",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_NullCallback },
#endif
#endif
#if !defined(SQLITE_OMIT_UTF16)
 {/* zName:     */ "encoding",
  /* ePragTyp:  */ PragTyp_ENCODING,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },

 {/* zName:     */ "freelist_count",
  /* ePragTyp:  */ PragTyp_HEADER_VALUE,
  /* ePragFlg:  */ PragFlg_ReadOnly|PragFlg_Result0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ BTREE_FREE_PAGE_COUNT },
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "full_column_names",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_FullColNames },
#endif
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
 {/* zName:     */ "fullfsync",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_FullFSync },
#endif
#if !defined(SQLITE_OMIT_SCHEMA_PRAGMAS)

 {/* zName:     */ "secure_delete",
  /* ePragTyp:  */ PragTyp_SECURE_DELETE,
  /* ePragFlg:  */ PragFlg_Result0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
#if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "short_column_names",
  /* ePragTyp:  */ PragTyp_FLAG,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ SQLITE_ShortColNames },
#endif
#endif
 {/* zName:     */ "shrink_memory",
  /* ePragTyp:  */ PragTyp_SHRINK_MEMORY,
  /* ePragFlg:  */ PragFlg_NoColumns,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
 {/* zName:     */ "soft_heap_limit",

#endif
#if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 {/* zName:     */ "temp_store",
  /* ePragTyp:  */ PragTyp_TEMP_STORE,
  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
#if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
#if !defined(SQLITE_OMIT_DEPRECATED)
 {/* zName:     */ "temp_store_directory",
  /* ePragTyp:  */ PragTyp_TEMP_STORE_DIRECTORY,
  /* ePragFlg:  */ PragFlg_NoColumns1,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
#endif
#if defined(SQLITE_HAS_CODEC)
 {/* zName:     */ "textkey",
  /* ePragTyp:  */ PragTyp_KEY,
  /* ePragFlg:  */ 0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 4 },

  sqlite3 *db = pParse->db;
  u64 savedFlags;

  savedFlags = db->flags;
  db->flags &= ~(u64)SQLITE_FullColNames;
  db->flags |= SQLITE_ShortColNames;
  sqlite3SelectPrep(pParse, pSelect, 0);
  db->flags = savedFlags;
  if( pParse->nErr ) return 0;
  while( pSelect->pPrior ) pSelect = pSelect->pPrior;

  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
  if( pTab==0 ){
    return 0;
  }
  /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
  ** is disabled */
  assert( db->lookaside.bDisable );

  hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngKey);

  /* There is one entry in the aRegIdx[] array for each index on the table
  ** being updated.  Fill in aRegIdx[] with a register number that will hold
  ** the key for accessing each index.
  */
  if( onError==OE_Replace ) bReplace = 1;
  for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    int reg;
    if( chngKey || hasFK>1 || pIdx==pPk
     || indexWhereClauseMightChange(pIdx,aXRef,chngRowid)
    ){
      reg = ++pParse->nMem;
      pParse->nMem += pIdx->nColumn;
    }else{
      reg = 0;
      for(i=0; i<pIdx->nKeyCol; i++){
        if( indexColumnIsBeingUpdated(pIdx, i, aXRef, chngRowid) ){
          reg = ++pParse->nMem;
          pParse->nMem += pIdx->nColumn;

          if( onError==OE_Default && pIdx->onError==OE_Replace ){

            bReplace = 1;
          }
          break;
        }
      }
    }
    if( reg==0 ) aToOpen[j+1] = 0;

  VdbeCoverageIf(v, eCond==0);
  VdbeCoverageIf(v, eCond==1);
  VdbeCoverageIf(v, eCond==2);
  sqlite3VdbeAddOp3(v, aOp[eCond], regZero, sqlite3VdbeCurrentAddr(v)+2, reg);
  VdbeCoverageNeverNullIf(v, eCond==0);
  VdbeCoverageNeverNullIf(v, eCond==1);
  VdbeCoverageNeverNullIf(v, eCond==2);
  sqlite3MayAbort(pParse);
  sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_ERROR, OE_Abort);
  sqlite3VdbeAppendP4(v, (void*)azErr[eCond], P4_STATIC);
  sqlite3ReleaseTempReg(pParse, regZero);
}

/*
** Return the number of arguments passed to the window-function associated

      **
      **      expr1 IN ()
      **      expr1 NOT IN ()
      **
      ** simplify to constants 0 (false) and 1 (true), respectively,
      ** regardless of the value of expr1.
      */
      if( IN_RENAME_OBJECT==0 ){
        sqlite3ExprDelete(pParse->db, yymsp[-4].minor.yy490);
        yymsp[-4].minor.yy490 = sqlite3ExprAlloc(pParse->db, TK_INTEGER,&sqlite3IntTokens[yymsp[-3].minor.yy96],1);
      }
    }else if( yymsp[-1].minor.yy42->nExpr==1 ){
      /* Expressions of the form:
      **
      **      expr1 IN (?1)
      **      expr1 NOT IN (?2)
      **
      ** with exactly one value on the RHS can be simplified to something

/*
** Terminator values for position-lists and column-lists.
*/
#define POS_COLUMN  (1)     /* Column-list terminator */
#define POS_END     (0)     /* Position-list terminator */ 

/*
** The assert_fts3_nc() macro is similar to the assert() macro, except that it
** is used for assert() conditions that are true only if it can be 
** guranteed that the database is not corrupt.
*/
#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
SQLITE_API extern int sqlite3_fts3_may_be_corrupt;
# define assert_fts3_nc(x) assert(sqlite3_fts3_may_be_corrupt || (x))
#else
# define assert_fts3_nc(x) assert(x)
#endif

/*
** This section provides definitions to allow the
** FTS3 extension to be compiled outside of the 
** amalgamation.
*/
#ifndef SQLITE_AMALGAMATION
/*

#ifndef SQLITE_AMALGAMATION
# if defined(SQLITE_DEBUG)
SQLITE_PRIVATE int sqlite3Fts3Always(int b) { assert( b ); return b; }
SQLITE_PRIVATE int sqlite3Fts3Never(int b)  { assert( !b ); return b; }
# endif
#endif

/*
** This variable is set to false when running tests for which the on disk
** structures should not be corrupt. Otherwise, true. If it is false, extra
** assert() conditions in the fts3 code are activated - conditions that are
** only true if it is guaranteed that the fts3 database is not corrupt.
*/
SQLITE_API int sqlite3_fts3_may_be_corrupt = 1;

/* 
** Write a 64-bit variable-length integer to memory starting at p[0].
** The length of data written will be between 1 and FTS3_VARINT_MAX bytes.
** The number of bytes written is returned.
*/
SQLITE_PRIVATE int sqlite3Fts3PutVarint(char *p, sqlite_int64 v){
  unsigned char *q = (unsigned char *) p;

  ** The space required to store the output is therefore the sum of the
  ** sizes of the two inputs, plus enough space for exactly one of the input
  ** docids to grow. 
  **
  ** A symetric argument may be made if the doclists are in descending 
  ** order.
  */
  aOut = sqlite3_malloc64((i64)n1+n2+FTS3_VARINT_MAX-1+FTS3_BUFFER_PADDING);
  if( !aOut ) return SQLITE_NOMEM;

  p = aOut;
  fts3GetDeltaVarint3(&p1, pEnd1, 0, &i1);
  fts3GetDeltaVarint3(&p2, pEnd2, 0, &i2);
  while( p1 || p2 ){
    sqlite3_int64 iDiff = DOCID_CMP(i1, i2);

      fts3GetDeltaVarint3(&p2, pEnd2, bDescDoclist, &i2);
    }
  }

  if( rc!=SQLITE_OK ){
    sqlite3_free(aOut);
    p = aOut = 0;
  }else{
    assert( (p-aOut)<=n1+n2+FTS3_VARINT_MAX-1 );
    memset(&aOut[(p-aOut)], 0, FTS3_BUFFER_PADDING);
  }
  *paOut = aOut;
  *pnOut = (int)(p-aOut);

  return rc;
}

/*
** This function does a "phrase" merge of two doclists. In a phrase merge,
** the output contains a copy of each position from the right-hand input
** doclist for which there is a position in the left-hand input doclist

**
** Discard the contents of the pending terms table.
*/
static int fts3RollbackToMethod(sqlite3_vtab *pVtab, int iSavepoint){
  Fts3Table *p = (Fts3Table*)pVtab;
  UNUSED_PARAMETER(iSavepoint);
  assert( p->inTransaction );

  TESTONLY( p->mxSavepoint = iSavepoint );
  sqlite3Fts3PendingTermsClear(p);
  return SQLITE_OK;
}

/*
** Return true if zName is the extension on one of the shadow tables used

static sqlite3_int64 getAbsoluteLevel(
  Fts3Table *p,                   /* FTS3 table handle */
  int iLangid,                    /* Language id */
  int iIndex,                     /* Index in p->aIndex[] */
  int iLevel                      /* Level of segments */
){
  sqlite3_int64 iBase;            /* First absolute level for iLangid/iIndex */
  assert_fts3_nc( iLangid>=0 );
  assert( p->nIndex>0 );
  assert( iIndex>=0 && iIndex<p->nIndex );

  iBase = ((sqlite3_int64)iLangid * p->nIndex + iIndex) * FTS3_SEGDIR_MAXLEVEL;
  return iBase + iLevel;
}

    rc = sqlite3_reset(pStmt);
    if( rc!=SQLITE_OK ) return rc;
  }
  nData = pWriter->nData;

  nPrefix = fts3PrefixCompress(pWriter->zTerm, pWriter->nTerm, zTerm, nTerm);
  nSuffix = nTerm-nPrefix;

  /* If nSuffix is zero or less, then zTerm/nTerm must be a prefix of 
  ** pWriter->zTerm/pWriter->nTerm. i.e. must be equal to or less than when
  ** compared with BINARY collation. This indicates corruption.  */
  if( nSuffix<=0 ) return FTS_CORRUPT_VTAB;

  /* Figure out how many bytes are required by this new entry */
  nReq = sqlite3Fts3VarintLen(nPrefix) +    /* varint containing prefix size */
    sqlite3Fts3VarintLen(nSuffix) +         /* varint containing suffix size */
    nSuffix +                               /* Term suffix */
    sqlite3Fts3VarintLen(nDoclist) +        /* Size of doclist */
    nDoclist;                               /* Doclist data */

**   Query for the details of phrase match iIdx within the current row.
**   Phrase matches are numbered starting from zero, so the iIdx argument
**   should be greater than or equal to zero and smaller than the value
**   output by xInstCount().
**
**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
**   to the column in which it occurs and *piOff the token offset of the




**   first token of the phrase. Returns SQLITE_OK if successful, or an error
**   code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. 
**
** xRowid:
**   Returns the rowid of the current row.
**

#ifdef SQLITE_DEBUG
SQLITE_API extern int sqlite3_fts5_may_be_corrupt;
# define assert_nc(x) assert(sqlite3_fts5_may_be_corrupt || (x))
#else
# define assert_nc(x) assert(x)
#endif

/*
** A version of memcmp() that does not cause asan errors if one of the pointer
** parameters is NULL and the number of bytes to compare is zero.
*/
#define fts5Memcmp(s1, s2, n) ((n)==0 ? 0 : memcmp((s1), (s2), (n)))

/* Mark a function parameter as unused, to suppress nuisance compiler
** warnings. */
#ifndef UNUSED_PARAM
# define UNUSED_PARAM(X)  (void)(X)
#endif

#ifndef UNUSED_PARAM2

)

/* Write and decode big-endian 32-bit integer values */
static void sqlite3Fts5Put32(u8*, int);
static int sqlite3Fts5Get32(const u8*);

#define FTS5_POS2COLUMN(iPos) (int)(iPos >> 32)
#define FTS5_POS2OFFSET(iPos) (int)(iPos & 0x7FFFFFFF)

typedef struct Fts5PoslistReader Fts5PoslistReader;
struct Fts5PoslistReader {
  /* Variables used only by sqlite3Fts5PoslistIterXXX() functions. */
  const u8 *a;                    /* Position list to iterate through */
  int n;                          /* Size of buffer at a[] in bytes */
  int i;                          /* Current offset in a[] */

  int ip = 0;
  int ic = 0;
  int iOff = 0;
  int iFirst = -1;
  int nInst;
  int nScore = 0;
  int iLast = 0;
  sqlite3_int64 iEnd = (sqlite3_int64)iPos + nToken;

  rc = pApi->xInstCount(pFts, &nInst);
  for(i=0; i<nInst && rc==SQLITE_OK; i++){
    rc = pApi->xInst(pFts, i, &ip, &ic, &iOff);
    if( rc==SQLITE_OK && ic==iCol && iOff>=iPos && iOff<iEnd ){
      nScore += (aSeen[ip] ? 1 : 1000);
      aSeen[ip] = 1;
      if( iFirst<0 ) iFirst = iOff;
      iLast = iOff + pApi->xPhraseSize(pFts, ip);
    }
  }

  *pnScore = nScore;
  if( piPos ){
    sqlite3_int64 iAdj = iFirst - (nToken - (iLast-iFirst)) / 2;
    if( (iAdj+nToken)>nDocsize ) iAdj = nDocsize - nToken;
    if( iAdj<0 ) iAdj = 0;
    *piPos = iAdj;
  }

  return rc;
}

    int iVal;
    fts5FastGetVarint32(a, i, iVal);
    if( iVal==1 ){
      fts5FastGetVarint32(a, i, iVal);
      iOff = ((i64)iVal) << 32;
      fts5FastGetVarint32(a, i, iVal);
    }
    *piOff = iOff + ((iVal-2) & 0x7FFFFFFF);
    *pi = i;
    return 0;
  }
}


/*

** Return -ve if pLeft is smaller than pRight, 0 if they are equal or
** +ve if pRight is smaller than pLeft. In other words:
**
**     res = *pLeft - *pRight
*/
static int fts5BufferCompare(Fts5Buffer *pLeft, Fts5Buffer *pRight){
  int nCmp = MIN(pLeft->n, pRight->n);
  int res = fts5Memcmp(pLeft->p, pRight->p, nCmp);
  return (res==0 ? (pLeft->n - pRight->n) : res);
}

static int fts5LeafFirstTermOff(Fts5Data *pLeaf){
  int ret;
  fts5GetVarint32(&pLeaf->p[pLeaf->szLeaf], ret);
  return ret;

  if( p1->pLeaf || p2->pLeaf ){
    if( p1->pLeaf==0 ){
      assert( pRes->iFirst==i2 );
    }else if( p2->pLeaf==0 ){
      assert( pRes->iFirst==i1 );
    }else{
      int nMin = MIN(p1->term.n, p2->term.n);
      int res = fts5Memcmp(p1->term.p, p2->term.p, nMin);
      if( res==0 ) res = p1->term.n - p2->term.n;

      if( res==0 ){
        assert( pRes->bTermEq==1 );
        assert( p1->iRowid!=p2->iRowid );
        res = ((p1->iRowid > p2->iRowid)==pIter->bRev) ? -1 : 1;
      }else{

      int iLvl, iSeg;
      int i;
      u32 mask;
      memset(aUsed, 0, sizeof(aUsed));
      for(iLvl=0; iLvl<pStruct->nLevel; iLvl++){
        for(iSeg=0; iSeg<pStruct->aLevel[iLvl].nSeg; iSeg++){
          int iId = pStruct->aLevel[iLvl].aSeg[iSeg].iSegid;
          if( iId<=FTS5_MAX_SEGMENT && iId>0 ){
            aUsed[(iId-1) / 32] |= (u32)1 << ((iId-1) % 32);
          }
        }
      }

      for(i=0; aUsed[i]==0xFFFFFFFF; i++);
      mask = aUsed[i];

** incremental merge operation. This function is called if the incremental
** merge step has finished but the input has not been completely exhausted.
*/
static void fts5TrimSegments(Fts5Index *p, Fts5Iter *pIter){
  int i;
  Fts5Buffer buf;
  memset(&buf, 0, sizeof(Fts5Buffer));
  for(i=0; i<pIter->nSeg && p->rc==SQLITE_OK; i++){
    Fts5SegIter *pSeg = &pIter->aSeg[i];
    if( pSeg->pSeg==0 ){
      /* no-op */
    }else if( pSeg->pLeaf==0 ){
      /* All keys from this input segment have been transfered to the output.
      ** Set both the first and last page-numbers to 0 to indicate that the
      ** segment is now empty. */
      pSeg->pSeg->pgnoLast = 0;
      pSeg->pSeg->pgnoFirst = 0;
    }else{
      int iOff = pSeg->iTermLeafOffset;     /* Offset on new first leaf page */
      i64 iLeafRowid;
      Fts5Data *pData;
      int iId = pSeg->pSeg->iSegid;
      u8 aHdr[4] = {0x00, 0x00, 0x00, 0x00};

      iLeafRowid = FTS5_SEGMENT_ROWID(iId, pSeg->iTermLeafPgno);
      pData = fts5DataRead(p, iLeafRowid);
      if( pData ){
        if( iOff>pData->szLeaf ){
          /* This can occur if the pages that the segments occupy overlap - if
          ** a single page has been assigned to more than one segment. In
          ** this case a prior iteration of this loop may have corrupted the
          ** segment currently being trimmed.  */
          p->rc = FTS5_CORRUPT;
        }else{
          fts5BufferZero(&buf);
          fts5BufferGrow(&p->rc, &buf, pData->nn);
          fts5BufferAppendBlob(&p->rc, &buf, sizeof(aHdr), aHdr);
          fts5BufferAppendVarint(&p->rc, &buf, pSeg->term.n);
          fts5BufferAppendBlob(&p->rc, &buf, pSeg->term.n, pSeg->term.p);
          fts5BufferAppendBlob(&p->rc, &buf, pData->szLeaf-iOff,&pData->p[iOff]);
          if( p->rc==SQLITE_OK ){
            /* Set the szLeaf field */
            fts5PutU16(&buf.p[2], (u16)buf.n);
          }

          /* Set up the new page-index array */
          fts5BufferAppendVarint(&p->rc, &buf, 4);
          if( pSeg->iLeafPgno==pSeg->iTermLeafPgno 
              && pSeg->iEndofDoclist<pData->szLeaf 
            ){
            int nDiff = pData->szLeaf - pSeg->iEndofDoclist;
            fts5BufferAppendVarint(&p->rc, &buf, buf.n - 1 - nDiff - 4);
            fts5BufferAppendBlob(&p->rc, &buf, 
                pData->nn - pSeg->iPgidxOff, &pData->p[pSeg->iPgidxOff]
                );
          }


          pSeg->pSeg->pgnoFirst = pSeg->iTermLeafPgno;
          fts5DataDelete(p, FTS5_SEGMENT_ROWID(iId, 1), iLeafRowid);
          fts5DataWrite(p, iLeafRowid, buf.p, buf.n);
        }
        fts5DataRelease(pData);
      }
    }
  }
  fts5BufferFree(&buf);
}

static void fts5MergeChunkCallback(

  ){
    Fts5SegIter *pSegIter = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
    int nPos;                     /* position-list size field value */
    int nTerm;
    const u8 *pTerm;

    pTerm = fts5MultiIterTerm(pIter, &nTerm);
    if( nTerm!=term.n || fts5Memcmp(pTerm, term.p, nTerm) ){
      if( pnRem && writer.nLeafWritten>nRem ){
        break;
      }
      fts5BufferSet(&p->rc, &term, nTerm, pTerm);
      bTermWritten =0;
    }

        }

        /* WRITEPOSLISTSIZE */
        fts5BufferSafeAppendVarint(&out, tmp.n * 2);
        fts5BufferSafeAppendBlob(&out, tmp.p, tmp.n);
        fts5DoclistIterNext(&i1);
        fts5DoclistIterNext(&i2);
        assert( out.n<=(p1->n+p2->n+9) );
        if( i1.aPoslist==0 || i2.aPoslist==0 ) break;
      }
    }

    if( i1.aPoslist ){
      fts5MergeAppendDocid(&out, iLastRowid, i1.iRowid);
      fts5BufferSafeAppendBlob(&out, i1.aPoslist, i1.aEof - i1.aPoslist);

      if( p->rc==SQLITE_OK ){
        xMerge(p, &doclist, &aBuf[i]);
      }
      fts5BufferFree(&aBuf[i]);
    }
    fts5MultiIterFree(p1);

    pData = fts5IdxMalloc(p, sizeof(Fts5Data)+doclist.n+FTS5_DATA_ZERO_PADDING);
    if( pData ){
      pData->p = (u8*)&pData[1];
      pData->nn = pData->szLeaf = doclist.n;
      if( doclist.n ) memcpy(pData->p, doclist.p, doclist.n);
      fts5MultiIterNew2(p, pData, bDesc, ppIter);
    }
    fts5BufferFree(&doclist);

      iOff = fts5LeafFirstTermOff(pLeaf);
      iRowidOff = fts5LeafFirstRowidOff(pLeaf);
      if( iRowidOff>=iOff || iOff>=pLeaf->szLeaf ){
        p->rc = FTS5_CORRUPT;
      }else{
        iOff += fts5GetVarint32(&pLeaf->p[iOff], nTerm);
        res = fts5Memcmp(&pLeaf->p[iOff], zIdxTerm, MIN(nTerm, nIdxTerm));
        if( res==0 ) res = nTerm - nIdxTerm;
        if( res<0 ) p->rc = FTS5_CORRUPT;
      }

      fts5IntegrityCheckPgidx(p, pLeaf);
    }
    fts5DataRelease(pLeaf);

** correctly for the current view. Return SQLITE_OK if successful, or an
** SQLite error code otherwise.
*/
static int fts5CacheInstArray(Fts5Cursor *pCsr){
  int rc = SQLITE_OK;
  Fts5PoslistReader *aIter;       /* One iterator for each phrase */
  int nIter;                      /* Number of iterators/phrases */
  int nCol = ((Fts5Table*)pCsr->base.pVtab)->pConfig->nCol;
  
  nIter = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
  if( pCsr->aInstIter==0 ){
    sqlite3_int64 nByte = sizeof(Fts5PoslistReader) * nIter;
    pCsr->aInstIter = (Fts5PoslistReader*)sqlite3Fts5MallocZero(&rc, nByte);
  }
  aIter = pCsr->aInstIter;

          }
        }

        aInst = &pCsr->aInst[3 * (nInst-1)];
        aInst[0] = iBest;
        aInst[1] = FTS5_POS2COLUMN(aIter[iBest].iPos);
        aInst[2] = FTS5_POS2OFFSET(aIter[iBest].iPos);
        if( aInst[1]<0 || aInst[1]>=nCol ){
          rc = FTS5_CORRUPT;
          break;
        }
        sqlite3Fts5PoslistReaderNext(&aIter[iBest]);
      }
    }

    pCsr->nInstCount = nInst;
    CsrFlagClear(pCsr, FTS5CSR_REQUIRE_INST);
  }

static void fts5SourceIdFunc(
  sqlite3_context *pCtx,          /* Function call context */
  int nArg,                       /* Number of args */
  sqlite3_value **apUnused        /* Function arguments */
){
  assert( nArg==0 );
  UNUSED_PARAM2(nArg, apUnused);
  sqlite3_result_text(pCtx, "fts5: 2019-01-26 23:34:50 a3ea1a822d3a110f4f186f2fc8550f435c8c98635d058096b7be9d4df7066b8b", -1, SQLITE_TRANSIENT);
}

/*
** Return true if zName is the extension on one of the shadow tables used
** by this module.
*/
static int fts5ShadowName(const char *zName){

#endif
  return rc;
}
#endif /* SQLITE_CORE */
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_STMTVTAB) */

/************** End of stmt.c ************************************************/
#if __LINE__!=221670
#undef SQLITE_SOURCE_ID
#define SQLITE_SOURCE_ID      "2019-01-27 02:45:32 9cf8ebd141aa2eb661d457624c76433bd9e4abfdef04aa52e28bc169172calt2"
#endif
/* Return the source-id for this library */
SQLITE_API const char *sqlite3_sourceid(void){ return SQLITE_SOURCE_ID; }
/************************** End of sqlite3.c ******************************/

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.27.0"
#define SQLITE_VERSION_NUMBER 3027000
#define SQLITE_SOURCE_ID      "2019-01-27 02:45:32 9cf8ebd141aa2eb661d457624c76433bd9e4abfdef04aa52e28bc169172calt1"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
** layer a hint of how large the database file will grow to be during the
** current transaction.  This hint is not guaranteed to be accurate but it
** is often close.  The underlying VFS might choose to preallocate database
** file space based on this hint in order to help writes to the database
** file run faster.
**
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
** implements [sqlite3_deserialize()] to set an upper bound on the size
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
** If the integer pointed to is negative, then it is filled in with the
** current limit.  Otherwise the limit is set to the larger of the value
** of the integer pointed to and the current database size.  The integer
** pointed to is set to the new limit.
**
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
** extends and truncates the database file in chunks of a size specified
** by the user. The fourth argument to [sqlite3_file_control()] should 
** point to an integer (type int) containing the new chunk-size to use
** for the nominated database. Allocating database file space in large
** chunks (say 1MB at a time), may reduce file-system fragmentation and

#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
#define SQLITE_FCNTL_PDB                    30
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
#define SQLITE_FCNTL_DATA_VERSION           35
#define SQLITE_FCNTL_SIZE_LIMIT             36

/* deprecated names */
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO

**   Query for the details of phrase match iIdx within the current row.
**   Phrase matches are numbered starting from zero, so the iIdx argument
**   should be greater than or equal to zero and smaller than the value
**   output by xInstCount().
**
**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
**   to the column in which it occurs and *piOff the token offset of the




**   first token of the phrase. Returns SQLITE_OK if successful, or an error
**   code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. 
**
** xRowid:
**   Returns the rowid of the current row.
**

  *  Make the chronological forum display feature available to all users,
     and make it the default format on mobile devices.
  *  Break out Wiki setup into a separate /setup_wiki page, accessible
     on the standard menus through Admin/Wiki.
  *  Add "Next" and "Previous" buttons on the /wdiff page, allowing
     the user to step through the versions of a wiki page.
  *  Improve the display of the /whistory page.
  *  Omit the "HH:MM" timestamps on timeline graphs on narrow-screen
     devices, to improve horizontal space uses.  This helps make Fossil
     more mobile-friendly.
  *  Enhance /wcontent to show a sortable list of Wiki pages together
     with the number of revisions and the most recent change time for
     each page.
  *  Hyperlinks to Wiki pages on the /timeline go to the specific
     version of the Wiki page named in the timeline, not to the latest
     version.
  *  Enhancements to the "amend", "tag", and "reparent" commands, including
     adding options --override-date, --override-user, and --dry-run.
  *  Add the global --comment-format command-line option and the
     comment-format setting to control the display of the command-line
     timeline.
  *  Change the "fossil reparent" command so that it only works from 
     within an active checkout.
  *  On the /setup_ucap_list, show administrators how many users have
     each capability.  The counts are a hyperlink to the /setup_ulist
     page showing the subset of users that have that capability.
  *  Provide the ability to redirect all HTTP pages to HTTPS.  Formerly
     one could cause this to occur for the /login page only.  That option
     still exists, but the redirect can now also be done for all pages.
  *  "Compress" the built-in javascript by omitting comments and
     leading and trailing whitespace.
  *  Detect when the repository used by a checkout is swapped out for
     a clone that uses different RID values, and make appropriate adjustments
     to the checkout database to avoid any problems.
  *  Add the backoffice-disable setting to completely disable the
     backoffice feature.
  *  Update the built-in SQLite to version 3.27.0 alpha.
  *  Various other small enhancements to webpages and documentation.


<a name='v2_7'></a>
<h2>Changes for Version 2.7 (2018-09-22)</h2>

  *  Add the [./alerts.md|email alerts] feature for commits, ticket