/* blast.h -- interface for blast.c
Copyright (C) 2003, 2012, 2013 Mark Adler
version 1.3, 24 Aug 2013
This software is provided 'as-is', without any express or implied
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Mark Adler firstname.lastname@example.org
* blast() decompresses the PKWare Data Compression Library (DCL) compressed
* format. It provides the same functionality as the explode() function in
* that library. (Note: PKWare overused the "implode" verb, and the format
* used by their library implode() function is completely different and
* incompatible with the implode compression method supported by PKZIP.)
* The binary mode for stdio functions should be used to assure that the
* compressed data is not corrupted when read or written. For example:
* fopen(..., "rb") and fopen(..., "wb").
typedef unsigned (*blast_in)(void *how, unsigned char **buf);
typedef int (*blast_out)(void *how, unsigned char *buf, unsigned len);
/* Definitions for input/output functions passed to blast(). See below for
* what the provided functions need to do.
int blast(blast_in infun, void *inhow, blast_out outfun, void *outhow,
unsigned *left, unsigned char **in);
/* Decompress input to output using the provided infun() and outfun() calls.
* On success, the return value of blast() is zero. If there is an error in
* the source data, i.e. it is not in the proper format, then a negative value
* is returned. If there is not enough input available or there is not enough
* output space, then a positive error is returned.
* The input function is invoked: len = infun(how, &buf), where buf is set by
* infun() to point to the input buffer, and infun() returns the number of
* available bytes there. If infun() returns zero, then blast() returns with
* an input error. (blast() only asks for input if it needs it.) inhow is for
* use by the application to pass an input descriptor to infun(), if desired.
* If left and in are not NULL and *left is not zero when blast() is called,
* then the *left bytes are *in are consumed for input before infun() is used.
* The output function is invoked: err = outfun(how, buf, len), where the bytes
* to be written are buf[0..len-1]. If err is not zero, then blast() returns
* with an output error. outfun() is always called with len <= 4096. outhow
* is for use by the application to pass an output descriptor to outfun(), if
* If there is any unused input, *left is set to the number of bytes that were
* read and *in points to them. Otherwise *left is set to zero and *in is set
* to NULL. If left or in are NULL, then they are not set.
* The return codes are:
* 2: ran out of input before completing decompression
* 1: output error before completing decompression
* 0: successful decompression
* -1: literal flag not zero or one
* -2: dictionary size not in 4..6
* -3: distance is too far back
* At the bottom of blast.c is an example program that uses blast() that can be
* compiled to produce a command-line decompression filter by defining TEST.