1b33c96954667ba382fa595baf7b31290bfdd517vboxsync/* blast.h -- interface for blast.c
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync Copyright (C) 2003 Mark Adler
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync version 1.1, 16 Feb 2003
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync This software is provided 'as-is', without any express or implied
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync warranty. In no event will the author be held liable for any damages
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync arising from the use of this software.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync Permission is granted to anyone to use this software for any purpose,
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync including commercial applications, and to alter it and redistribute it
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync freely, subject to the following restrictions:
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync 1. The origin of this software must not be misrepresented; you must not
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync claim that you wrote the original software. If you use this software
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync in a product, an acknowledgment in the product documentation would be
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync appreciated but is not required.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync 2. Altered source versions must be plainly marked as such, and must not be
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync misrepresented as being the original software.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync 3. This notice may not be removed or altered from any source distribution.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync Mark Adler madler@alumni.caltech.edu
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * blast() decompresses the PKWare Data Compression Library (DCL) compressed
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * format. It provides the same functionality as the explode() function in
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * that library. (Note: PKWare overused the "implode" verb, and the format
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * used by their library implode() function is completely different and
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * incompatible with the implode compression method supported by PKZIP.)
1b33c96954667ba382fa595baf7b31290bfdd517vboxsynctypedef unsigned (*blast_in)(void *how, unsigned char **buf);
1b33c96954667ba382fa595baf7b31290bfdd517vboxsynctypedef int (*blast_out)(void *how, unsigned char *buf, unsigned len);
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync/* Definitions for input/output functions passed to blast(). See below for
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * what the provided functions need to do.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsyncint blast(blast_in infun, void *inhow, blast_out outfun, void *outhow);
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync/* Decompress input to output using the provided infun() and outfun() calls.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * On success, the return value of blast() is zero. If there is an error in
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * the source data, i.e. it is not in the proper format, then a negative value
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * is returned. If there is not enough input available or there is not enough
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * output space, then a positive error is returned.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * The input function is invoked: len = infun(how, &buf), where buf is set by
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * infun() to point to the input buffer, and infun() returns the number of
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * available bytes there. If infun() returns zero, then blast() returns with
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * an input error. (blast() only asks for input if it needs it.) inhow is for
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * use by the application to pass an input descriptor to infun(), if desired.
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * The output function is invoked: err = outfun(how, buf, len), where the bytes
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * to be written are buf[0..len-1]. If err is not zero, then blast() returns
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * with an output error. outfun() is always called with len <= 4096. outhow
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * is for use by the application to pass an output descriptor to outfun(), if
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * The return codes are:
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * 2: ran out of input before completing decompression
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * 1: output error before completing decompression
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * 0: successful decompression
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * -1: literal flag not zero or one
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * -2: dictionary size not in 4..6
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * -3: distance is too far back
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * At the bottom of blast.c is an example program that uses blast() that can be
1b33c96954667ba382fa595baf7b31290bfdd517vboxsync * compiled to produce a command-line decompression filter by defining TEST.