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jeremybenn |
/* $FreeBSD: src/sys/net/zlib.h,v 1.7 1999/12/29 04:38:38 peter Exp $ */
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/*
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* This file is derived from zlib.h and zconf.h from the zlib-1.0.4
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* distribution by Jean-loup Gailly and Mark Adler, with some additions
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* by Paul Mackerras to aid in implementing Deflate compression and
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* decompression for PPP packets.
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*/
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/*
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* ==FILEVERSION 971127==
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*
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* This marker is used by the Linux installation script to determine
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* whether an up-to-date version of this file is already installed.
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*/
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/* +++ zlib.h */
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/* zlib.h -- interface of the 'zlib' general purpose compression library
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version 1.0.4, Jul 24th, 1996.
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Copyright (C) 1995-1996 Jean-loup Gailly and Mark Adler
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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Jean-loup Gailly Mark Adler
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gzip@prep.ai.mit.edu madler@alumni.caltech.edu
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The data format used by the zlib library is described by RFCs (Request for
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Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt
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(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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*/
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#ifndef _ZLIB_H
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#define _ZLIB_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* +++ zconf.h */
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/* zconf.h -- configuration of the zlib compression library
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* Copyright (C) 1995-1996 Jean-loup Gailly.
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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/* From: zconf.h,v 1.20 1996/07/02 15:09:28 me Exp $ */
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#ifndef _ZCONF_H
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#define _ZCONF_H
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/*
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* If you *really* need a unique prefix for all types and library functions,
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* compile with -DZ_PREFIX. The "standard" zlib should be compiled without it.
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*/
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#ifdef Z_PREFIX
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# define deflateInit_ z_deflateInit_
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# define deflate z_deflate
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# define deflateEnd z_deflateEnd
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# define inflateInit_ z_inflateInit_
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# define inflate z_inflate
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# define inflateEnd z_inflateEnd
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# define deflateInit2_ z_deflateInit2_
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# define deflateSetDictionary z_deflateSetDictionary
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# define deflateCopy z_deflateCopy
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# define deflateReset z_deflateReset
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# define deflateParams z_deflateParams
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# define inflateInit2_ z_inflateInit2_
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# define inflateSetDictionary z_inflateSetDictionary
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# define inflateSync z_inflateSync
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# define inflateReset z_inflateReset
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# define compress z_compress
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# define uncompress z_uncompress
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# define adler32 z_adler32
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# define crc32 z_crc32
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# define get_crc_table z_get_crc_table
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# define Byte z_Byte
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# define uInt z_uInt
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# define uLong z_uLong
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# define Bytef z_Bytef
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# define charf z_charf
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# define intf z_intf
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# define uIntf z_uIntf
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# define uLongf z_uLongf
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# define voidpf z_voidpf
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# define voidp z_voidp
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#endif
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#if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32)
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# define WIN32
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#endif
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#if defined(__GNUC__) || defined(WIN32) || defined(__386__) || defined(i386)
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# ifndef __32BIT__
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# define __32BIT__
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# endif
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#endif
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#if defined(__MSDOS__) && !defined(MSDOS)
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# define MSDOS
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#endif
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/*
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* Compile with -DMAXSEG_64K if the alloc function cannot allocate more
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* than 64k bytes at a time (needed on systems with 16-bit int).
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*/
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#if defined(MSDOS) && !defined(__32BIT__)
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# define MAXSEG_64K
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#endif
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#ifdef MSDOS
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# define UNALIGNED_OK
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#endif
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#if (defined(MSDOS) || defined(_WINDOWS) || defined(WIN32)) && !defined(STDC)
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# define STDC
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#endif
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#if (defined(__STDC__) || defined(__cplusplus)) && !defined(STDC)
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# define STDC
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#endif
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#ifndef STDC
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# ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */
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# define const
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# endif
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#endif
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/* Some Mac compilers merge all .h files incorrectly: */
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#if defined(__MWERKS__) || defined(applec) ||defined(THINK_C) ||defined(__SC__)
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# define NO_DUMMY_DECL
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#endif
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/* Maximum value for memLevel in deflateInit2 */
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#ifndef MAX_MEM_LEVEL
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# ifdef MAXSEG_64K
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# define MAX_MEM_LEVEL 8
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# else
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# define MAX_MEM_LEVEL 9
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# endif
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#endif
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/* Maximum value for windowBits in deflateInit2 and inflateInit2 */
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#ifndef MAX_WBITS
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# define MAX_WBITS 15 /* 32K LZ77 window */
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#endif
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/* The memory requirements for deflate are (in bytes):
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1 << (windowBits+2) + 1 << (memLevel+9)
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that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values)
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plus a few kilobytes for small objects. For example, if you want to reduce
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the default memory requirements from 256K to 128K, compile with
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make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
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Of course this will generally degrade compression (there's no free lunch).
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The memory requirements for inflate are (in bytes) 1 << windowBits
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that is, 32K for windowBits=15 (default value) plus a few kilobytes
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for small objects.
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*/
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/* Type declarations */
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#ifndef OF /* function prototypes */
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# ifdef STDC
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# define OF(args) args
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# else
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# define OF(args) ()
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# endif
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#endif
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/* The following definitions for FAR are needed only for MSDOS mixed
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* model programming (small or medium model with some far allocations).
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* This was tested only with MSC; for other MSDOS compilers you may have
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* to define NO_MEMCPY in zutil.h. If you don't need the mixed model,
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* just define FAR to be empty.
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*/
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#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(__32BIT__)
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/* MSC small or medium model */
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# define SMALL_MEDIUM
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# ifdef _MSC_VER
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# define FAR __far
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# else
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# define FAR far
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# endif
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#endif
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#if defined(__BORLANDC__) && (defined(__SMALL__) || defined(__MEDIUM__))
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# ifndef __32BIT__
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# define SMALL_MEDIUM
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# define FAR __far
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# endif
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#endif
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#ifndef FAR
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# define FAR
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#endif
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typedef unsigned char Byte; /* 8 bits */
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typedef unsigned int uInt; /* 16 bits or more */
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typedef unsigned long uLong; /* 32 bits or more */
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#if defined(__BORLANDC__) && defined(SMALL_MEDIUM)
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/* Borland C/C++ ignores FAR inside typedef */
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# define Bytef Byte FAR
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#else
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typedef Byte FAR Bytef;
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#endif
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typedef char FAR charf;
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typedef int FAR intf;
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typedef uInt FAR uIntf;
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typedef uLong FAR uLongf;
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#ifdef STDC
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typedef void FAR *voidpf;
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typedef void *voidp;
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#else
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typedef Byte FAR *voidpf;
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typedef Byte *voidp;
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#endif
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/* Compile with -DZLIB_DLL for Windows DLL support */
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#if (defined(_WINDOWS) || defined(WINDOWS)) && defined(ZLIB_DLL)
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# include <windows.h>
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# define EXPORT WINAPI
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#else
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# define EXPORT
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#endif
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#endif /* _ZCONF_H */
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/* --- zconf.h */
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#define ZLIB_VERSION "1.0.4P"
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/*
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The 'zlib' compression library provides in-memory compression and
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decompression functions, including integrity checks of the uncompressed
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data. This version of the library supports only one compression method
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(deflation) but other algorithms may be added later and will have the same
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stream interface.
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For compression the application must provide the output buffer and
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may optionally provide the input buffer for optimization. For decompression,
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the application must provide the input buffer and may optionally provide
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the output buffer for optimization.
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Compression can be done in a single step if the buffers are large
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enough (for example if an input file is mmap'ed), or can be done by
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repeated calls of the compression function. In the latter case, the
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application must provide more input and/or consume the output
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(providing more output space) before each call.
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The library does not install any signal handler. It is recommended to
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add at least a handler for SIGSEGV when decompressing; the library checks
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the consistency of the input data whenever possible but may go nuts
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for some forms of corrupted input.
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*/
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typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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typedef void (*free_func) OF((voidpf opaque, voidpf address));
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struct internal_state;
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typedef struct z_stream_s {
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Bytef *next_in; /* next input byte */
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uInt avail_in; /* number of bytes available at next_in */
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uLong total_in; /* total nb of input bytes read so far */
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Bytef *next_out; /* next output byte should be put there */
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uInt avail_out; /* remaining free space at next_out */
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uLong total_out; /* total nb of bytes output so far */
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const char *msg; /* last error message, NULL if no error */
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struct internal_state FAR *state; /* not visible by applications */
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alloc_func zalloc; /* used to allocate the internal state */
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free_func zfree; /* used to free the internal state */
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voidpf opaque; /* private data object passed to zalloc and zfree */
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int data_type; /* best guess about the data type: ascii or binary */
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uLong adler; /* adler32 value of the uncompressed data */
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uLong reserved; /* reserved for future use */
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} z_stream;
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295 |
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|
296 |
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typedef z_stream FAR *z_streamp;
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|
298 |
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/*
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The application must update next_in and avail_in when avail_in has
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dropped to zero. It must update next_out and avail_out when avail_out
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has dropped to zero. The application must initialize zalloc, zfree and
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opaque before calling the init function. All other fields are set by the
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compression library and must not be updated by the application.
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304 |
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305 |
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The opaque value provided by the application will be passed as the first
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parameter for calls of zalloc and zfree. This can be useful for custom
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memory management. The compression library attaches no meaning to the
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opaque value.
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309 |
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|
310 |
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zalloc must return Z_NULL if there is not enough memory for the object.
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311 |
|
|
On 16-bit systems, the functions zalloc and zfree must be able to allocate
|
312 |
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exactly 65536 bytes, but will not be required to allocate more than this
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313 |
|
|
if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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pointers returned by zalloc for objects of exactly 65536 bytes *must*
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315 |
|
|
have their offset normalized to zero. The default allocation function
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316 |
|
|
provided by this library ensures this (see zutil.c). To reduce memory
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317 |
|
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requirements and avoid any allocation of 64K objects, at the expense of
|
318 |
|
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compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
|
319 |
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|
320 |
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The fields total_in and total_out can be used for statistics or
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progress reports. After compression, total_in holds the total size of
|
322 |
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the uncompressed data and may be saved for use in the decompressor
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323 |
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(particularly if the decompressor wants to decompress everything in
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324 |
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a single step).
|
325 |
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*/
|
326 |
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|
327 |
|
|
/* constants */
|
328 |
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|
329 |
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#define Z_NO_FLUSH 0
|
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|
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#define Z_PARTIAL_FLUSH 1
|
331 |
|
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#define Z_PACKET_FLUSH 2
|
332 |
|
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#define Z_SYNC_FLUSH 3
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333 |
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#define Z_FULL_FLUSH 4
|
334 |
|
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#define Z_FINISH 5
|
335 |
|
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/* Allowed flush values; see deflate() below for details */
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336 |
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|
337 |
|
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#define Z_OK 0
|
338 |
|
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#define Z_STREAM_END 1
|
339 |
|
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#define Z_NEED_DICT 2
|
340 |
|
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#define Z_ERRNO (-1)
|
341 |
|
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#define Z_STREAM_ERROR (-2)
|
342 |
|
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#define Z_DATA_ERROR (-3)
|
343 |
|
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#define Z_MEM_ERROR (-4)
|
344 |
|
|
#define Z_BUF_ERROR (-5)
|
345 |
|
|
#define Z_VERSION_ERROR (-6)
|
346 |
|
|
/* Return codes for the compression/decompression functions. Negative
|
347 |
|
|
* values are errors, positive values are used for special but normal events.
|
348 |
|
|
*/
|
349 |
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|
350 |
|
|
#define Z_NO_COMPRESSION 0
|
351 |
|
|
#define Z_BEST_SPEED 1
|
352 |
|
|
#define Z_BEST_COMPRESSION 9
|
353 |
|
|
#define Z_DEFAULT_COMPRESSION (-1)
|
354 |
|
|
/* compression levels */
|
355 |
|
|
|
356 |
|
|
#define Z_FILTERED 1
|
357 |
|
|
#define Z_HUFFMAN_ONLY 2
|
358 |
|
|
#define Z_DEFAULT_STRATEGY 0
|
359 |
|
|
/* compression strategy; see deflateInit2() below for details */
|
360 |
|
|
|
361 |
|
|
#define Z_BINARY 0
|
362 |
|
|
#define Z_ASCII 1
|
363 |
|
|
#define Z_UNKNOWN 2
|
364 |
|
|
/* Possible values of the data_type field */
|
365 |
|
|
|
366 |
|
|
#define Z_DEFLATED 8
|
367 |
|
|
/* The deflate compression method (the only one supported in this version) */
|
368 |
|
|
|
369 |
|
|
#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
|
370 |
|
|
|
371 |
|
|
#define zlib_version zlibVersion()
|
372 |
|
|
/* for compatibility with versions < 1.0.2 */
|
373 |
|
|
|
374 |
|
|
/* basic functions */
|
375 |
|
|
|
376 |
|
|
extern const char * EXPORT zlibVersion OF((void));
|
377 |
|
|
/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
|
378 |
|
|
If the first character differs, the library code actually used is
|
379 |
|
|
not compatible with the zlib.h header file used by the application.
|
380 |
|
|
This check is automatically made by deflateInit and inflateInit.
|
381 |
|
|
*/
|
382 |
|
|
|
383 |
|
|
/*
|
384 |
|
|
extern int EXPORT deflateInit OF((z_streamp strm, int level));
|
385 |
|
|
|
386 |
|
|
Initializes the internal stream state for compression. The fields
|
387 |
|
|
zalloc, zfree and opaque must be initialized before by the caller.
|
388 |
|
|
If zalloc and zfree are set to Z_NULL, deflateInit updates them to
|
389 |
|
|
use default allocation functions.
|
390 |
|
|
|
391 |
|
|
The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
|
392 |
|
|
1 gives best speed, 9 gives best compression, 0 gives no compression at
|
393 |
|
|
all (the input data is simply copied a block at a time).
|
394 |
|
|
Z_DEFAULT_COMPRESSION requests a default compromise between speed and
|
395 |
|
|
compression (currently equivalent to level 6).
|
396 |
|
|
|
397 |
|
|
deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
|
398 |
|
|
enough memory, Z_STREAM_ERROR if level is not a valid compression level,
|
399 |
|
|
Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
|
400 |
|
|
with the version assumed by the caller (ZLIB_VERSION).
|
401 |
|
|
msg is set to null if there is no error message. deflateInit does not
|
402 |
|
|
perform any compression: this will be done by deflate().
|
403 |
|
|
*/
|
404 |
|
|
|
405 |
|
|
|
406 |
|
|
extern int EXPORT deflate OF((z_streamp strm, int flush));
|
407 |
|
|
/*
|
408 |
|
|
Performs one or both of the following actions:
|
409 |
|
|
|
410 |
|
|
- Compress more input starting at next_in and update next_in and avail_in
|
411 |
|
|
accordingly. If not all input can be processed (because there is not
|
412 |
|
|
enough room in the output buffer), next_in and avail_in are updated and
|
413 |
|
|
processing will resume at this point for the next call of deflate().
|
414 |
|
|
|
415 |
|
|
- Provide more output starting at next_out and update next_out and avail_out
|
416 |
|
|
accordingly. This action is forced if the parameter flush is non zero.
|
417 |
|
|
Forcing flush frequently degrades the compression ratio, so this parameter
|
418 |
|
|
should be set only when necessary (in interactive applications).
|
419 |
|
|
Some output may be provided even if flush is not set.
|
420 |
|
|
|
421 |
|
|
Before the call of deflate(), the application should ensure that at least
|
422 |
|
|
one of the actions is possible, by providing more input and/or consuming
|
423 |
|
|
more output, and updating avail_in or avail_out accordingly; avail_out
|
424 |
|
|
should never be zero before the call. The application can consume the
|
425 |
|
|
compressed output when it wants, for example when the output buffer is full
|
426 |
|
|
(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
|
427 |
|
|
and with zero avail_out, it must be called again after making room in the
|
428 |
|
|
output buffer because there might be more output pending.
|
429 |
|
|
|
430 |
|
|
If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
|
431 |
|
|
block is terminated and flushed to the output buffer so that the
|
432 |
|
|
decompressor can get all input data available so far. For method 9, a future
|
433 |
|
|
variant on method 8, the current block will be flushed but not terminated.
|
434 |
|
|
Z_SYNC_FLUSH has the same effect as partial flush except that the compressed
|
435 |
|
|
output is byte aligned (the compressor can clear its internal bit buffer)
|
436 |
|
|
and the current block is always terminated; this can be useful if the
|
437 |
|
|
compressor has to be restarted from scratch after an interruption (in which
|
438 |
|
|
case the internal state of the compressor may be lost).
|
439 |
|
|
If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
|
440 |
|
|
special marker is output and the compression dictionary is discarded; this
|
441 |
|
|
is useful to allow the decompressor to synchronize if one compressed block
|
442 |
|
|
has been damaged (see inflateSync below). Flushing degrades compression and
|
443 |
|
|
so should be used only when necessary. Using Z_FULL_FLUSH too often can
|
444 |
|
|
seriously degrade the compression. If deflate returns with avail_out == 0,
|
445 |
|
|
this function must be called again with the same value of the flush
|
446 |
|
|
parameter and more output space (updated avail_out), until the flush is
|
447 |
|
|
complete (deflate returns with non-zero avail_out).
|
448 |
|
|
|
449 |
|
|
If the parameter flush is set to Z_PACKET_FLUSH, the compression
|
450 |
|
|
block is terminated, and a zero-length stored block is output,
|
451 |
|
|
omitting the length bytes (the effect of this is that the 3-bit type
|
452 |
|
|
code 000 for a stored block is output, and the output is then
|
453 |
|
|
byte-aligned). This is designed for use at the end of a PPP packet.
|
454 |
|
|
|
455 |
|
|
If the parameter flush is set to Z_FINISH, pending input is processed,
|
456 |
|
|
pending output is flushed and deflate returns with Z_STREAM_END if there
|
457 |
|
|
was enough output space; if deflate returns with Z_OK, this function must be
|
458 |
|
|
called again with Z_FINISH and more output space (updated avail_out) but no
|
459 |
|
|
more input data, until it returns with Z_STREAM_END or an error. After
|
460 |
|
|
deflate has returned Z_STREAM_END, the only possible operations on the
|
461 |
|
|
stream are deflateReset or deflateEnd.
|
462 |
|
|
|
463 |
|
|
Z_FINISH can be used immediately after deflateInit if all the compression
|
464 |
|
|
is to be done in a single step. In this case, avail_out must be at least
|
465 |
|
|
0.1% larger than avail_in plus 12 bytes. If deflate does not return
|
466 |
|
|
Z_STREAM_END, then it must be called again as described above.
|
467 |
|
|
|
468 |
|
|
deflate() may update data_type if it can make a good guess about
|
469 |
|
|
the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
|
470 |
|
|
binary. This field is only for information purposes and does not affect
|
471 |
|
|
the compression algorithm in any manner.
|
472 |
|
|
|
473 |
|
|
deflate() returns Z_OK if some progress has been made (more input
|
474 |
|
|
processed or more output produced), Z_STREAM_END if all input has been
|
475 |
|
|
consumed and all output has been produced (only when flush is set to
|
476 |
|
|
Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
|
477 |
|
|
if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible.
|
478 |
|
|
*/
|
479 |
|
|
|
480 |
|
|
|
481 |
|
|
extern int EXPORT deflateEnd OF((z_streamp strm));
|
482 |
|
|
/*
|
483 |
|
|
All dynamically allocated data structures for this stream are freed.
|
484 |
|
|
This function discards any unprocessed input and does not flush any
|
485 |
|
|
pending output.
|
486 |
|
|
|
487 |
|
|
deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
|
488 |
|
|
stream state was inconsistent, Z_DATA_ERROR if the stream was freed
|
489 |
|
|
prematurely (some input or output was discarded). In the error case,
|
490 |
|
|
msg may be set but then points to a static string (which must not be
|
491 |
|
|
deallocated).
|
492 |
|
|
*/
|
493 |
|
|
|
494 |
|
|
|
495 |
|
|
/*
|
496 |
|
|
extern int EXPORT inflateInit OF((z_streamp strm));
|
497 |
|
|
|
498 |
|
|
Initializes the internal stream state for decompression. The fields
|
499 |
|
|
zalloc, zfree and opaque must be initialized before by the caller. If
|
500 |
|
|
zalloc and zfree are set to Z_NULL, inflateInit updates them to use default
|
501 |
|
|
allocation functions.
|
502 |
|
|
|
503 |
|
|
inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
|
504 |
|
|
enough memory, Z_VERSION_ERROR if the zlib library version is incompatible
|
505 |
|
|
with the version assumed by the caller. msg is set to null if there is no
|
506 |
|
|
error message. inflateInit does not perform any decompression: this will be
|
507 |
|
|
done by inflate().
|
508 |
|
|
*/
|
509 |
|
|
|
510 |
|
|
#if defined(__FreeBSD__) && defined(_KERNEL)
|
511 |
|
|
#define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
|
512 |
|
|
#endif
|
513 |
|
|
|
514 |
|
|
extern int EXPORT inflate OF((z_streamp strm, int flush));
|
515 |
|
|
/*
|
516 |
|
|
Performs one or both of the following actions:
|
517 |
|
|
|
518 |
|
|
- Decompress more input starting at next_in and update next_in and avail_in
|
519 |
|
|
accordingly. If not all input can be processed (because there is not
|
520 |
|
|
enough room in the output buffer), next_in is updated and processing
|
521 |
|
|
will resume at this point for the next call of inflate().
|
522 |
|
|
|
523 |
|
|
- Provide more output starting at next_out and update next_out and avail_out
|
524 |
|
|
accordingly. inflate() provides as much output as possible, until there
|
525 |
|
|
is no more input data or no more space in the output buffer (see below
|
526 |
|
|
about the flush parameter).
|
527 |
|
|
|
528 |
|
|
Before the call of inflate(), the application should ensure that at least
|
529 |
|
|
one of the actions is possible, by providing more input and/or consuming
|
530 |
|
|
more output, and updating the next_* and avail_* values accordingly.
|
531 |
|
|
The application can consume the uncompressed output when it wants, for
|
532 |
|
|
example when the output buffer is full (avail_out == 0), or after each
|
533 |
|
|
call of inflate(). If inflate returns Z_OK and with zero avail_out, it
|
534 |
|
|
must be called again after making room in the output buffer because there
|
535 |
|
|
might be more output pending.
|
536 |
|
|
|
537 |
|
|
If the parameter flush is set to Z_PARTIAL_FLUSH or Z_PACKET_FLUSH,
|
538 |
|
|
inflate flushes as much output as possible to the output buffer. The
|
539 |
|
|
flushing behavior of inflate is not specified for values of the flush
|
540 |
|
|
parameter other than Z_PARTIAL_FLUSH, Z_PACKET_FLUSH or Z_FINISH, but the
|
541 |
|
|
current implementation actually flushes as much output as possible
|
542 |
|
|
anyway. For Z_PACKET_FLUSH, inflate checks that once all the input data
|
543 |
|
|
has been consumed, it is expecting to see the length field of a stored
|
544 |
|
|
block; if not, it returns Z_DATA_ERROR.
|
545 |
|
|
|
546 |
|
|
inflate() should normally be called until it returns Z_STREAM_END or an
|
547 |
|
|
error. However if all decompression is to be performed in a single step
|
548 |
|
|
(a single call of inflate), the parameter flush should be set to
|
549 |
|
|
Z_FINISH. In this case all pending input is processed and all pending
|
550 |
|
|
output is flushed; avail_out must be large enough to hold all the
|
551 |
|
|
uncompressed data. (The size of the uncompressed data may have been saved
|
552 |
|
|
by the compressor for this purpose.) The next operation on this stream must
|
553 |
|
|
be inflateEnd to deallocate the decompression state. The use of Z_FINISH
|
554 |
|
|
is never required, but can be used to inform inflate that a faster routine
|
555 |
|
|
may be used for the single inflate() call.
|
556 |
|
|
|
557 |
|
|
inflate() returns Z_OK if some progress has been made (more input
|
558 |
|
|
processed or more output produced), Z_STREAM_END if the end of the
|
559 |
|
|
compressed data has been reached and all uncompressed output has been
|
560 |
|
|
produced, Z_NEED_DICT if a preset dictionary is needed at this point (see
|
561 |
|
|
inflateSetDictionary below), Z_DATA_ERROR if the input data was corrupted,
|
562 |
|
|
Z_STREAM_ERROR if the stream structure was inconsistent (for example if
|
563 |
|
|
next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
|
564 |
|
|
Z_BUF_ERROR if no progress is possible or if there was not enough room in
|
565 |
|
|
the output buffer when Z_FINISH is used. In the Z_DATA_ERROR case, the
|
566 |
|
|
application may then call inflateSync to look for a good compression block.
|
567 |
|
|
In the Z_NEED_DICT case, strm->adler is set to the Adler32 value of the
|
568 |
|
|
dictionary chosen by the compressor.
|
569 |
|
|
*/
|
570 |
|
|
|
571 |
|
|
|
572 |
|
|
extern int EXPORT inflateEnd OF((z_streamp strm));
|
573 |
|
|
/*
|
574 |
|
|
All dynamically allocated data structures for this stream are freed.
|
575 |
|
|
This function discards any unprocessed input and does not flush any
|
576 |
|
|
pending output.
|
577 |
|
|
|
578 |
|
|
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
|
579 |
|
|
was inconsistent. In the error case, msg may be set but then points to a
|
580 |
|
|
static string (which must not be deallocated).
|
581 |
|
|
*/
|
582 |
|
|
|
583 |
|
|
/* Advanced functions */
|
584 |
|
|
|
585 |
|
|
/*
|
586 |
|
|
The following functions are needed only in some special applications.
|
587 |
|
|
*/
|
588 |
|
|
|
589 |
|
|
/*
|
590 |
|
|
extern int EXPORT deflateInit2 OF((z_streamp strm,
|
591 |
|
|
int level,
|
592 |
|
|
int method,
|
593 |
|
|
int windowBits,
|
594 |
|
|
int memLevel,
|
595 |
|
|
int strategy));
|
596 |
|
|
|
597 |
|
|
This is another version of deflateInit with more compression options. The
|
598 |
|
|
fields next_in, zalloc, zfree and opaque must be initialized before by
|
599 |
|
|
the caller.
|
600 |
|
|
|
601 |
|
|
The method parameter is the compression method. It must be Z_DEFLATED in
|
602 |
|
|
this version of the library. (Method 9 will allow a 64K history buffer and
|
603 |
|
|
partial block flushes.)
|
604 |
|
|
|
605 |
|
|
The windowBits parameter is the base two logarithm of the window size
|
606 |
|
|
(the size of the history buffer). It should be in the range 8..15 for this
|
607 |
|
|
version of the library (the value 16 will be allowed for method 9). Larger
|
608 |
|
|
values of this parameter result in better compression at the expense of
|
609 |
|
|
memory usage. The default value is 15 if deflateInit is used instead.
|
610 |
|
|
|
611 |
|
|
The memLevel parameter specifies how much memory should be allocated
|
612 |
|
|
for the internal compression state. memLevel=1 uses minimum memory but
|
613 |
|
|
is slow and reduces compression ratio; memLevel=9 uses maximum memory
|
614 |
|
|
for optimal speed. The default value is 8. See zconf.h for total memory
|
615 |
|
|
usage as a function of windowBits and memLevel.
|
616 |
|
|
|
617 |
|
|
The strategy parameter is used to tune the compression algorithm. Use the
|
618 |
|
|
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
619 |
|
|
filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
620 |
|
|
string match). Filtered data consists mostly of small values with a
|
621 |
|
|
somewhat random distribution. In this case, the compression algorithm is
|
622 |
|
|
tuned to compress them better. The effect of Z_FILTERED is to force more
|
623 |
|
|
Huffman coding and less string matching; it is somewhat intermediate
|
624 |
|
|
between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects
|
625 |
|
|
the compression ratio but not the correctness of the compressed output even
|
626 |
|
|
if it is not set appropriately.
|
627 |
|
|
|
628 |
|
|
If next_in is not null, the library will use this buffer to hold also
|
629 |
|
|
some history information; the buffer must either hold the entire input
|
630 |
|
|
data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in
|
631 |
|
|
is null, the library will allocate its own history buffer (and leave next_in
|
632 |
|
|
null). next_out need not be provided here but must be provided by the
|
633 |
|
|
application for the next call of deflate().
|
634 |
|
|
|
635 |
|
|
If the history buffer is provided by the application, next_in must
|
636 |
|
|
must never be changed by the application since the compressor maintains
|
637 |
|
|
information inside this buffer from call to call; the application
|
638 |
|
|
must provide more input only by increasing avail_in. next_in is always
|
639 |
|
|
reset by the library in this case.
|
640 |
|
|
|
641 |
|
|
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
|
642 |
|
|
not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
|
643 |
|
|
an invalid method). msg is set to null if there is no error message.
|
644 |
|
|
deflateInit2 does not perform any compression: this will be done by
|
645 |
|
|
deflate().
|
646 |
|
|
*/
|
647 |
|
|
|
648 |
|
|
extern int EXPORT deflateSetDictionary OF((z_streamp strm,
|
649 |
|
|
const Bytef *dictionary,
|
650 |
|
|
uInt dictLength));
|
651 |
|
|
/*
|
652 |
|
|
Initializes the compression dictionary (history buffer) from the given
|
653 |
|
|
byte sequence without producing any compressed output. This function must
|
654 |
|
|
be called immediately after deflateInit or deflateInit2, before any call
|
655 |
|
|
of deflate. The compressor and decompressor must use exactly the same
|
656 |
|
|
dictionary (see inflateSetDictionary).
|
657 |
|
|
The dictionary should consist of strings (byte sequences) that are likely
|
658 |
|
|
to be encountered later in the data to be compressed, with the most commonly
|
659 |
|
|
used strings preferably put towards the end of the dictionary. Using a
|
660 |
|
|
dictionary is most useful when the data to be compressed is short and
|
661 |
|
|
can be predicted with good accuracy; the data can then be compressed better
|
662 |
|
|
than with the default empty dictionary. In this version of the library,
|
663 |
|
|
only the last 32K bytes of the dictionary are used.
|
664 |
|
|
Upon return of this function, strm->adler is set to the Adler32 value
|
665 |
|
|
of the dictionary; the decompressor may later use this value to determine
|
666 |
|
|
which dictionary has been used by the compressor. (The Adler32 value
|
667 |
|
|
applies to the whole dictionary even if only a subset of the dictionary is
|
668 |
|
|
actually used by the compressor.)
|
669 |
|
|
|
670 |
|
|
deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
|
671 |
|
|
parameter is invalid (such as NULL dictionary) or the stream state
|
672 |
|
|
is inconsistent (for example if deflate has already been called for this
|
673 |
|
|
stream). deflateSetDictionary does not perform any compression: this will
|
674 |
|
|
be done by deflate().
|
675 |
|
|
*/
|
676 |
|
|
|
677 |
|
|
extern int EXPORT deflateCopy OF((z_streamp dest,
|
678 |
|
|
z_streamp source));
|
679 |
|
|
/*
|
680 |
|
|
Sets the destination stream as a complete copy of the source stream. If
|
681 |
|
|
the source stream is using an application-supplied history buffer, a new
|
682 |
|
|
buffer is allocated for the destination stream. The compressed output
|
683 |
|
|
buffer is always application-supplied. It's the responsibility of the
|
684 |
|
|
application to provide the correct values of next_out and avail_out for the
|
685 |
|
|
next call of deflate.
|
686 |
|
|
|
687 |
|
|
This function can be useful when several compression strategies will be
|
688 |
|
|
tried, for example when there are several ways of pre-processing the input
|
689 |
|
|
data with a filter. The streams that will be discarded should then be freed
|
690 |
|
|
by calling deflateEnd. Note that deflateCopy duplicates the internal
|
691 |
|
|
compression state which can be quite large, so this strategy is slow and
|
692 |
|
|
can consume lots of memory.
|
693 |
|
|
|
694 |
|
|
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
695 |
|
|
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
696 |
|
|
(such as zalloc being NULL). msg is left unchanged in both source and
|
697 |
|
|
destination.
|
698 |
|
|
*/
|
699 |
|
|
|
700 |
|
|
extern int EXPORT deflateReset OF((z_streamp strm));
|
701 |
|
|
/*
|
702 |
|
|
This function is equivalent to deflateEnd followed by deflateInit,
|
703 |
|
|
but does not free and reallocate all the internal compression state.
|
704 |
|
|
The stream will keep the same compression level and any other attributes
|
705 |
|
|
that may have been set by deflateInit2.
|
706 |
|
|
|
707 |
|
|
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
708 |
|
|
stream state was inconsistent (such as zalloc or state being NULL).
|
709 |
|
|
*/
|
710 |
|
|
|
711 |
|
|
extern int EXPORT deflateParams OF((z_streamp strm, int level, int strategy));
|
712 |
|
|
/*
|
713 |
|
|
Dynamically update the compression level and compression strategy.
|
714 |
|
|
This can be used to switch between compression and straight copy of
|
715 |
|
|
the input data, or to switch to a different kind of input data requiring
|
716 |
|
|
a different strategy. If the compression level is changed, the input
|
717 |
|
|
available so far is compressed with the old level (and may be flushed);
|
718 |
|
|
the new level will take effect only at the next call of deflate().
|
719 |
|
|
|
720 |
|
|
Before the call of deflateParams, the stream state must be set as for
|
721 |
|
|
a call of deflate(), since the currently available input may have to
|
722 |
|
|
be compressed and flushed. In particular, strm->avail_out must be non-zero.
|
723 |
|
|
|
724 |
|
|
deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
|
725 |
|
|
stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
|
726 |
|
|
if strm->avail_out was zero.
|
727 |
|
|
*/
|
728 |
|
|
|
729 |
|
|
extern int EXPORT deflateOutputPending OF((z_streamp strm));
|
730 |
|
|
/*
|
731 |
|
|
Returns the number of bytes of output which are immediately
|
732 |
|
|
available from the compressor (i.e. without any further input
|
733 |
|
|
or flush).
|
734 |
|
|
*/
|
735 |
|
|
|
736 |
|
|
/*
|
737 |
|
|
extern int EXPORT inflateInit2 OF((z_streamp strm,
|
738 |
|
|
int windowBits));
|
739 |
|
|
|
740 |
|
|
This is another version of inflateInit with more compression options. The
|
741 |
|
|
fields next_out, zalloc, zfree and opaque must be initialized before by
|
742 |
|
|
the caller.
|
743 |
|
|
|
744 |
|
|
The windowBits parameter is the base two logarithm of the maximum window
|
745 |
|
|
size (the size of the history buffer). It should be in the range 8..15 for
|
746 |
|
|
this version of the library (the value 16 will be allowed soon). The
|
747 |
|
|
default value is 15 if inflateInit is used instead. If a compressed stream
|
748 |
|
|
with a larger window size is given as input, inflate() will return with
|
749 |
|
|
the error code Z_DATA_ERROR instead of trying to allocate a larger window.
|
750 |
|
|
|
751 |
|
|
If next_out is not null, the library will use this buffer for the history
|
752 |
|
|
buffer; the buffer must either be large enough to hold the entire output
|
753 |
|
|
data, or have at least 1<<windowBits bytes. If next_out is null, the
|
754 |
|
|
library will allocate its own buffer (and leave next_out null). next_in
|
755 |
|
|
need not be provided here but must be provided by the application for the
|
756 |
|
|
next call of inflate().
|
757 |
|
|
|
758 |
|
|
If the history buffer is provided by the application, next_out must
|
759 |
|
|
never be changed by the application since the decompressor maintains
|
760 |
|
|
history information inside this buffer from call to call; the application
|
761 |
|
|
can only reset next_out to the beginning of the history buffer when
|
762 |
|
|
avail_out is zero and all output has been consumed.
|
763 |
|
|
|
764 |
|
|
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
|
765 |
|
|
not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
|
766 |
|
|
windowBits < 8). msg is set to null if there is no error message.
|
767 |
|
|
inflateInit2 does not perform any decompression: this will be done by
|
768 |
|
|
inflate().
|
769 |
|
|
*/
|
770 |
|
|
|
771 |
|
|
extern int EXPORT inflateSetDictionary OF((z_streamp strm,
|
772 |
|
|
const Bytef *dictionary,
|
773 |
|
|
uInt dictLength));
|
774 |
|
|
/*
|
775 |
|
|
Initializes the decompression dictionary (history buffer) from the given
|
776 |
|
|
uncompressed byte sequence. This function must be called immediately after
|
777 |
|
|
a call of inflate if this call returned Z_NEED_DICT. The dictionary chosen
|
778 |
|
|
by the compressor can be determined from the Adler32 value returned by this
|
779 |
|
|
call of inflate. The compressor and decompressor must use exactly the same
|
780 |
|
|
dictionary (see deflateSetDictionary).
|
781 |
|
|
|
782 |
|
|
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
|
783 |
|
|
parameter is invalid (such as NULL dictionary) or the stream state is
|
784 |
|
|
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
|
785 |
|
|
expected one (incorrect Adler32 value). inflateSetDictionary does not
|
786 |
|
|
perform any decompression: this will be done by subsequent calls of
|
787 |
|
|
inflate().
|
788 |
|
|
*/
|
789 |
|
|
|
790 |
|
|
extern int EXPORT inflateSync OF((z_streamp strm));
|
791 |
|
|
/*
|
792 |
|
|
Skips invalid compressed data until the special marker (see deflate()
|
793 |
|
|
above) can be found, or until all available input is skipped. No output
|
794 |
|
|
is provided.
|
795 |
|
|
|
796 |
|
|
inflateSync returns Z_OK if the special marker has been found, Z_BUF_ERROR
|
797 |
|
|
if no more input was provided, Z_DATA_ERROR if no marker has been found,
|
798 |
|
|
or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
|
799 |
|
|
case, the application may save the current current value of total_in which
|
800 |
|
|
indicates where valid compressed data was found. In the error case, the
|
801 |
|
|
application may repeatedly call inflateSync, providing more input each time,
|
802 |
|
|
until success or end of the input data.
|
803 |
|
|
*/
|
804 |
|
|
|
805 |
|
|
extern int EXPORT inflateReset OF((z_streamp strm));
|
806 |
|
|
/*
|
807 |
|
|
This function is equivalent to inflateEnd followed by inflateInit,
|
808 |
|
|
but does not free and reallocate all the internal decompression state.
|
809 |
|
|
The stream will keep attributes that may have been set by inflateInit2.
|
810 |
|
|
|
811 |
|
|
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
812 |
|
|
stream state was inconsistent (such as zalloc or state being NULL).
|
813 |
|
|
*/
|
814 |
|
|
|
815 |
|
|
extern int inflateIncomp OF((z_stream *strm));
|
816 |
|
|
/*
|
817 |
|
|
This function adds the data at next_in (avail_in bytes) to the output
|
818 |
|
|
history without performing any output. There must be no pending output,
|
819 |
|
|
and the decompressor must be expecting to see the start of a block.
|
820 |
|
|
Calling this function is equivalent to decompressing a stored block
|
821 |
|
|
containing the data at next_in (except that the data is not output).
|
822 |
|
|
*/
|
823 |
|
|
|
824 |
|
|
/* utility functions */
|
825 |
|
|
|
826 |
|
|
/*
|
827 |
|
|
The following utility functions are implemented on top of the
|
828 |
|
|
basic stream-oriented functions. To simplify the interface, some
|
829 |
|
|
default options are assumed (compression level, window size,
|
830 |
|
|
standard memory allocation functions). The source code of these
|
831 |
|
|
utility functions can easily be modified if you need special options.
|
832 |
|
|
*/
|
833 |
|
|
|
834 |
|
|
extern int EXPORT compress OF((Bytef *dest, uLongf *destLen,
|
835 |
|
|
const Bytef *source, uLong sourceLen));
|
836 |
|
|
/*
|
837 |
|
|
Compresses the source buffer into the destination buffer. sourceLen is
|
838 |
|
|
the byte length of the source buffer. Upon entry, destLen is the total
|
839 |
|
|
size of the destination buffer, which must be at least 0.1% larger than
|
840 |
|
|
sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the
|
841 |
|
|
compressed buffer.
|
842 |
|
|
This function can be used to compress a whole file at once if the
|
843 |
|
|
input file is mmap'ed.
|
844 |
|
|
compress returns Z_OK if success, Z_MEM_ERROR if there was not
|
845 |
|
|
enough memory, Z_BUF_ERROR if there was not enough room in the output
|
846 |
|
|
buffer.
|
847 |
|
|
*/
|
848 |
|
|
|
849 |
|
|
extern int EXPORT uncompress OF((Bytef *dest, uLongf *destLen,
|
850 |
|
|
const Bytef *source, uLong sourceLen));
|
851 |
|
|
/*
|
852 |
|
|
Decompresses the source buffer into the destination buffer. sourceLen is
|
853 |
|
|
the byte length of the source buffer. Upon entry, destLen is the total
|
854 |
|
|
size of the destination buffer, which must be large enough to hold the
|
855 |
|
|
entire uncompressed data. (The size of the uncompressed data must have
|
856 |
|
|
been saved previously by the compressor and transmitted to the decompressor
|
857 |
|
|
by some mechanism outside the scope of this compression library.)
|
858 |
|
|
Upon exit, destLen is the actual size of the compressed buffer.
|
859 |
|
|
This function can be used to decompress a whole file at once if the
|
860 |
|
|
input file is mmap'ed.
|
861 |
|
|
|
862 |
|
|
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
863 |
|
|
enough memory, Z_BUF_ERROR if there was not enough room in the output
|
864 |
|
|
buffer, or Z_DATA_ERROR if the input data was corrupted.
|
865 |
|
|
*/
|
866 |
|
|
|
867 |
|
|
|
868 |
|
|
typedef voidp gzFile;
|
869 |
|
|
|
870 |
|
|
extern gzFile EXPORT gzopen OF((const char *path, const char *mode));
|
871 |
|
|
/*
|
872 |
|
|
Opens a gzip (.gz) file for reading or writing. The mode parameter
|
873 |
|
|
is as in fopen ("rb" or "wb") but can also include a compression level
|
874 |
|
|
("wb9"). gzopen can be used to read a file which is not in gzip format;
|
875 |
|
|
in this case gzread will directly read from the file without decompression.
|
876 |
|
|
gzopen returns NULL if the file could not be opened or if there was
|
877 |
|
|
insufficient memory to allocate the (de)compression state; errno
|
878 |
|
|
can be checked to distinguish the two cases (if errno is zero, the
|
879 |
|
|
zlib error is Z_MEM_ERROR).
|
880 |
|
|
*/
|
881 |
|
|
|
882 |
|
|
extern gzFile EXPORT gzdopen OF((int fd, const char *mode));
|
883 |
|
|
/*
|
884 |
|
|
gzdopen() associates a gzFile with the file descriptor fd. File
|
885 |
|
|
descriptors are obtained from calls like open, dup, creat, pipe or
|
886 |
|
|
fileno (in the file has been previously opened with fopen).
|
887 |
|
|
The mode parameter is as in gzopen.
|
888 |
|
|
The next call of gzclose on the returned gzFile will also close the
|
889 |
|
|
file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
|
890 |
|
|
descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
|
891 |
|
|
gzdopen returns NULL if there was insufficient memory to allocate
|
892 |
|
|
the (de)compression state.
|
893 |
|
|
*/
|
894 |
|
|
|
895 |
|
|
extern int EXPORT gzread OF((gzFile file, voidp buf, unsigned len));
|
896 |
|
|
/*
|
897 |
|
|
Reads the given number of uncompressed bytes from the compressed file.
|
898 |
|
|
If the input file was not in gzip format, gzread copies the given number
|
899 |
|
|
of bytes into the buffer.
|
900 |
|
|
gzread returns the number of uncompressed bytes actually read (0 for
|
901 |
|
|
end of file, -1 for error). */
|
902 |
|
|
|
903 |
|
|
extern int EXPORT gzwrite OF((gzFile file, const voidp buf, unsigned len));
|
904 |
|
|
/*
|
905 |
|
|
Writes the given number of uncompressed bytes into the compressed file.
|
906 |
|
|
gzwrite returns the number of uncompressed bytes actually written
|
907 |
|
|
(0 in case of error).
|
908 |
|
|
*/
|
909 |
|
|
|
910 |
|
|
extern int EXPORT gzflush OF((gzFile file, int flush));
|
911 |
|
|
/*
|
912 |
|
|
Flushes all pending output into the compressed file. The parameter
|
913 |
|
|
flush is as in the deflate() function. The return value is the zlib
|
914 |
|
|
error number (see function gzerror below). gzflush returns Z_OK if
|
915 |
|
|
the flush parameter is Z_FINISH and all output could be flushed.
|
916 |
|
|
gzflush should be called only when strictly necessary because it can
|
917 |
|
|
degrade compression.
|
918 |
|
|
*/
|
919 |
|
|
|
920 |
|
|
extern int EXPORT gzclose OF((gzFile file));
|
921 |
|
|
/*
|
922 |
|
|
Flushes all pending output if necessary, closes the compressed file
|
923 |
|
|
and deallocates all the (de)compression state. The return value is the zlib
|
924 |
|
|
error number (see function gzerror below).
|
925 |
|
|
*/
|
926 |
|
|
|
927 |
|
|
extern const char * EXPORT gzerror OF((gzFile file, int *errnum));
|
928 |
|
|
/*
|
929 |
|
|
Returns the error message for the last error which occurred on the
|
930 |
|
|
given compressed file. errnum is set to zlib error number. If an
|
931 |
|
|
error occurred in the file system and not in the compression library,
|
932 |
|
|
errnum is set to Z_ERRNO and the application may consult errno
|
933 |
|
|
to get the exact error code.
|
934 |
|
|
*/
|
935 |
|
|
|
936 |
|
|
/* checksum functions */
|
937 |
|
|
|
938 |
|
|
/*
|
939 |
|
|
These functions are not related to compression but are exported
|
940 |
|
|
anyway because they might be useful in applications using the
|
941 |
|
|
compression library.
|
942 |
|
|
*/
|
943 |
|
|
|
944 |
|
|
extern uLong EXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
|
945 |
|
|
|
946 |
|
|
/*
|
947 |
|
|
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
|
948 |
|
|
return the updated checksum. If buf is NULL, this function returns
|
949 |
|
|
the required initial value for the checksum.
|
950 |
|
|
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
|
951 |
|
|
much faster. Usage example:
|
952 |
|
|
|
953 |
|
|
uLong adler = adler32(0L, Z_NULL, 0);
|
954 |
|
|
|
955 |
|
|
while (read_buffer(buffer, length) != EOF) {
|
956 |
|
|
adler = adler32(adler, buffer, length);
|
957 |
|
|
}
|
958 |
|
|
if (adler != original_adler) error();
|
959 |
|
|
*/
|
960 |
|
|
|
961 |
|
|
extern uLong EXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
|
962 |
|
|
/*
|
963 |
|
|
Update a running crc with the bytes buf[0..len-1] and return the updated
|
964 |
|
|
crc. If buf is NULL, this function returns the required initial value
|
965 |
|
|
for the crc. Pre- and post-conditioning (one's complement) is performed
|
966 |
|
|
within this function so it shouldn't be done by the application.
|
967 |
|
|
Usage example:
|
968 |
|
|
|
969 |
|
|
uLong crc = crc32(0L, Z_NULL, 0);
|
970 |
|
|
|
971 |
|
|
while (read_buffer(buffer, length) != EOF) {
|
972 |
|
|
crc = crc32(crc, buffer, length);
|
973 |
|
|
}
|
974 |
|
|
if (crc != original_crc) error();
|
975 |
|
|
*/
|
976 |
|
|
|
977 |
|
|
|
978 |
|
|
/* various hacks, don't look :) */
|
979 |
|
|
|
980 |
|
|
/* deflateInit and inflateInit are macros to allow checking the zlib version
|
981 |
|
|
* and the compiler's view of z_stream:
|
982 |
|
|
*/
|
983 |
|
|
extern int EXPORT deflateInit_ OF((z_streamp strm, int level,
|
984 |
|
|
const char *version, int stream_size));
|
985 |
|
|
extern int EXPORT inflateInit_ OF((z_streamp strm,
|
986 |
|
|
const char *version, int stream_size));
|
987 |
|
|
extern int EXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
|
988 |
|
|
int windowBits, int memLevel, int strategy,
|
989 |
|
|
const char *version, int stream_size));
|
990 |
|
|
extern int EXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
|
991 |
|
|
const char *version, int stream_size));
|
992 |
|
|
#define deflateInit(strm, level) \
|
993 |
|
|
deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
|
994 |
|
|
#define inflateInit(strm) \
|
995 |
|
|
inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
|
996 |
|
|
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
|
997 |
|
|
deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
|
998 |
|
|
(strategy), ZLIB_VERSION, sizeof(z_stream))
|
999 |
|
|
#define inflateInit2(strm, windowBits) \
|
1000 |
|
|
inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
|
1001 |
|
|
|
1002 |
|
|
#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
|
1003 |
|
|
struct internal_state {int dummy;}; /* hack for buggy compilers */
|
1004 |
|
|
#endif
|
1005 |
|
|
|
1006 |
|
|
uLongf *get_crc_table OF((void)); /* can be used by asm versions of crc32() */
|
1007 |
|
|
|
1008 |
|
|
#ifdef __cplusplus
|
1009 |
|
|
}
|
1010 |
|
|
#endif
|
1011 |
|
|
|
1012 |
|
|
#endif /* _ZLIB_H */
|
1013 |
|
|
/* --- zlib.h */
|