100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* zlib.h -- interface of the 'zlib' general purpose compression library 209eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes version 1.2.7, May 2nd, 2012 300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Copyright (C) 1995-2012 Jean-loup Gailly and Mark Adler 500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This software is provided 'as-is', without any express or implied 700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes warranty. In no event will the authors be held liable for any damages 800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes arising from the use of this software. 900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Permission is granted to anyone to use this software for any purpose, 1100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes including commercial applications, and to alter it and redistribute it 1200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes freely, subject to the following restrictions: 1300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1. The origin of this software must not be misrepresented; you must not 1500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes claim that you wrote the original software. If you use this software 1600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in a product, an acknowledgment in the product documentation would be 1700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes appreciated but is not required. 1800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 2. Altered source versions must be plainly marked as such, and must not be 1900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes misrepresented as being the original software. 2000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 3. This notice may not be removed or altered from any source distribution. 2100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 2200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Jean-loup Gailly Mark Adler 2300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes jloup@gzip.org madler@alumni.caltech.edu 2400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 2500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 2600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The data format used by the zlib library is described by RFCs (Request for 2700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950 2800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format). 2900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 3000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 3100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#ifndef ZLIB_H 3200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define ZLIB_H 3300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 3400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#include "zconf.h" 3500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 3600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#ifdef __cplusplus 3700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughesextern "C" { 3800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 3900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 4009eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#define ZLIB_VERSION "1.2.7" 4109eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#define ZLIB_VERNUM 0x1270 4200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define ZLIB_VER_MAJOR 1 4300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define ZLIB_VER_MINOR 2 4409eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#define ZLIB_VER_REVISION 7 4500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define ZLIB_VER_SUBREVISION 0 4600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 4700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 4800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The 'zlib' compression library provides in-memory compression and 4900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decompression functions, including integrity checks of the uncompressed data. 5000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This version of the library supports only one compression method (deflation) 5100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes but other algorithms will be added later and will have the same stream 5200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes interface. 5300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 5400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Compression can be done in a single step if the buffers are large enough, 5500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes or can be done by repeated calls of the compression function. In the latter 5600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes case, the application must provide more input and/or consume the output 5700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (providing more output space) before each call. 5800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 5900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The compressed data format used by default by the in-memory functions is 6000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped 6100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes around a deflate stream, which is itself documented in RFC 1951. 6200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 6300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The library also supports reading and writing files in gzip (.gz) format 6400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with an interface similar to that of stdio using the functions that start 6500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with "gz". The gzip format is different from the zlib format. gzip is a 6600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. 6700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 6800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This library can optionally read and write gzip streams in memory as well. 6900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 7000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The zlib format was designed to be compact and fast for use in memory 7100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes and on communications channels. The gzip format was designed for single- 7200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file compression on file systems, has a larger header than zlib to maintain 7300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes directory information, and uses a different, slower check method than zlib. 7400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 7500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The library does not install any signal handler. The decoder checks 7600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the consistency of the compressed data, so the library should never crash 7700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes even in case of corrupted input. 7800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 7900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 8000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); 8100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef void (*free_func) OF((voidpf opaque, voidpf address)); 8200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 8300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughesstruct internal_state; 8400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 8500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef struct z_stream_s { 8600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_const Bytef *next_in; /* next input byte */ 8700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt avail_in; /* number of bytes available at next_in */ 8800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong total_in; /* total number of input bytes read so far */ 8900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 9000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Bytef *next_out; /* next output byte should be put there */ 9100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt avail_out; /* remaining free space at next_out */ 9200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong total_out; /* total number of bytes output so far */ 9300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 9400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_const char *msg; /* last error message, NULL if no error */ 9500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes struct internal_state FAR *state; /* not visible by applications */ 9600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 9700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes alloc_func zalloc; /* used to allocate the internal state */ 9800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes free_func zfree; /* used to free the internal state */ 9900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes voidpf opaque; /* private data object passed to zalloc and zfree */ 10000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 10100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int data_type; /* best guess about the data type: binary or text */ 10200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong adler; /* adler32 value of the uncompressed data */ 10300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong reserved; /* reserved for future use */ 10400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes} z_stream; 10500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 10600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef z_stream FAR *z_streamp; 10700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 10800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 10900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip header information passed to and from zlib routines. See RFC 1952 11000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for more details on the meanings of these fields. 11100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 11200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef struct gz_header_s { 11300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int text; /* true if compressed data believed to be text */ 11400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong time; /* modification time */ 11500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int xflags; /* extra flags (not used when writing a gzip file) */ 11600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int os; /* operating system */ 11700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Bytef *extra; /* pointer to extra field or Z_NULL if none */ 11800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt extra_len; /* extra field length (valid if extra != Z_NULL) */ 11900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt extra_max; /* space at extra (only when reading header) */ 12000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ 12100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt name_max; /* space at name (only when reading header) */ 12200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */ 12300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt comm_max; /* space at comment (only when reading header) */ 12400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int hcrc; /* true if there was or will be a header crc */ 12500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int done; /* true when done reading gzip header (not used 12600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes when writing a gzip file) */ 12700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes} gz_header; 12800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 12900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef gz_header FAR *gz_headerp; 13000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 13100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 13200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The application must update next_in and avail_in when avail_in has dropped 13300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to zero. It must update next_out and avail_out when avail_out has dropped 13400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to zero. The application must initialize zalloc, zfree and opaque before 13500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes calling the init function. All other fields are set by the compression 13600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes library and must not be updated by the application. 13700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 13800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The opaque value provided by the application will be passed as the first 13900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes parameter for calls of zalloc and zfree. This can be useful for custom 14000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory management. The compression library attaches no meaning to the 14100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes opaque value. 14200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 14300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zalloc must return Z_NULL if there is not enough memory for the object. 14400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If zlib is used in a multi-threaded application, zalloc and zfree must be 14500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes thread safe. 14600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 14700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes On 16-bit systems, the functions zalloc and zfree must be able to allocate 14800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes exactly 65536 bytes, but will not be required to allocate more than this if 14900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers 15000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes returned by zalloc for objects of exactly 65536 bytes *must* have their 15100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes offset normalized to zero. The default allocation function provided by this 15200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes library ensures this (see zutil.c). To reduce memory requirements and avoid 15300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes any allocation of 64K objects, at the expense of compression ratio, compile 15400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the library with -DMAX_WBITS=14 (see zconf.h). 15500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 15600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The fields total_in and total_out can be used for statistics or progress 15700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes reports. After compression, total_in holds the total size of the 15800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed data and may be saved for use in the decompressor (particularly 15900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if the decompressor wants to decompress everything in a single step). 16000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 16100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 16200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* constants */ 16300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 16400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_NO_FLUSH 0 16500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_PARTIAL_FLUSH 1 16600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_SYNC_FLUSH 2 16700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_FULL_FLUSH 3 16800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_FINISH 4 16900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_BLOCK 5 17000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_TREES 6 17100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* Allowed flush values; see deflate() and inflate() below for details */ 17200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 17300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_OK 0 17400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_STREAM_END 1 17500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_NEED_DICT 2 17600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_ERRNO (-1) 17700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_STREAM_ERROR (-2) 17800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_DATA_ERROR (-3) 17900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_MEM_ERROR (-4) 18000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_BUF_ERROR (-5) 18100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_VERSION_ERROR (-6) 18200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* Return codes for the compression/decompression functions. Negative values 18300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * are errors, positive values are used for special but normal events. 18400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 18500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 18600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_NO_COMPRESSION 0 18700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_BEST_SPEED 1 18800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_BEST_COMPRESSION 9 18900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_DEFAULT_COMPRESSION (-1) 19000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* compression levels */ 19100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 19200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_FILTERED 1 19300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_HUFFMAN_ONLY 2 19400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_RLE 3 19500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_FIXED 4 19600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_DEFAULT_STRATEGY 0 19700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* compression strategy; see deflateInit2() below for details */ 19800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 19900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_BINARY 0 20000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_TEXT 1 20100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ 20200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_UNKNOWN 2 20300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* Possible values of the data_type field (though see inflate()) */ 20400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 20500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_DEFLATED 8 20600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* The deflate compression method (the only one supported in this version) */ 20700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 20800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ 20900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 21000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define zlib_version zlibVersion() 21100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* for compatibility with versions < 1.0.2 */ 21200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 21300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 21400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* basic functions */ 21500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 21600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN const char * ZEXPORT zlibVersion OF((void)); 21700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* The application can compare zlibVersion and ZLIB_VERSION for consistency. 21800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the first character differs, the library code actually used is not 21900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compatible with the zlib.h header file used by the application. This check 22000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is automatically made by deflateInit and inflateInit. 22100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 22200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 22300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 22400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); 22500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 22600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Initializes the internal stream state for compression. The fields 22700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zalloc, zfree and opaque must be initialized before by the caller. If 22800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zalloc and zfree are set to Z_NULL, deflateInit updates them to use default 22900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes allocation functions. 23000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 23100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: 23200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1 gives best speed, 9 gives best compression, 0 gives no compression at all 23300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION 23400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes requests a default compromise between speed and compression (currently 23500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes equivalent to level 6). 23600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 23700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 23800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory, Z_STREAM_ERROR if level is not a valid compression level, or 23900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible 24000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with the version assumed by the caller (ZLIB_VERSION). msg is set to null 24100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if there is no error message. deflateInit does not perform any compression: 24200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes this will be done by deflate(). 24300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 24400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 24500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 24600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); 24700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 24800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate compresses as much data as possible, and stops when the input 24900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer becomes empty or the output buffer becomes full. It may introduce 25000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes some output latency (reading input without producing any output) except when 25100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes forced to flush. 25200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 25300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The detailed semantics are as follows. deflate performs one or both of the 25400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes following actions: 25500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 25600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes - Compress more input starting at next_in and update next_in and avail_in 25700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes accordingly. If not all input can be processed (because there is not 25800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough room in the output buffer), next_in and avail_in are updated and 25900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes processing will resume at this point for the next call of deflate(). 26000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 26100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes - Provide more output starting at next_out and update next_out and avail_out 26200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes accordingly. This action is forced if the parameter flush is non zero. 26300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Forcing flush frequently degrades the compression ratio, so this parameter 26400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes should be set only when necessary (in interactive applications). Some 26500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output may be provided even if flush is not set. 26600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 26700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Before the call of deflate(), the application should ensure that at least 26800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes one of the actions is possible, by providing more input and/or consuming more 26900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output, and updating avail_in or avail_out accordingly; avail_out should 27000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes never be zero before the call. The application can consume the compressed 27100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output when it wants, for example when the output buffer is full (avail_out 27200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes == 0), or after each call of deflate(). If deflate returns Z_OK and with 27300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zero avail_out, it must be called again after making room in the output 27400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer because there might be more output pending. 27500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 27600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to 27700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decide how much data to accumulate before producing output, in order to 27800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes maximize compression. 27900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 28000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the parameter flush is set to Z_SYNC_FLUSH, all pending output is 28100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes flushed to the output buffer and the output is aligned on a byte boundary, so 28200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that the decompressor can get all input data available so far. (In 28300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes particular avail_in is zero after the call if enough output space has been 28400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided before the call.) Flushing may degrade compression for some 28500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression algorithms and so it should be used only when necessary. This 28600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes completes the current deflate block and follows it with an empty stored block 28700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that is three bits plus filler bits to the next byte, followed by four bytes 28800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (00 00 ff ff). 28900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 29000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the 29100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output buffer, but the output is not aligned to a byte boundary. All of the 29200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. 29300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This completes the current deflate block and follows it with an empty fixed 29400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes codes block that is 10 bits long. This assures that enough bytes are output 29500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in order for the decompressor to finish the block before the empty fixed code 29600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes block. 29700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 29800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If flush is set to Z_BLOCK, a deflate block is completed and emitted, as 29900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to 30000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes seven bits of the current block are held to be written as the next byte after 30100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the next deflate block is completed. In this case, the decompressor may not 30200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes be provided enough bits at this point in order to complete decompression of 30300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the data provided so far to the compressor. It may need to wait for the next 30400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes block to be emitted. This is for advanced applications that need to control 30500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the emission of deflate blocks. 30600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 30700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If flush is set to Z_FULL_FLUSH, all output is flushed as with 30800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_SYNC_FLUSH, and the compression state is reset so that decompression can 30900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes restart from this point if previous compressed data has been damaged or if 31000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes random access is desired. Using Z_FULL_FLUSH too often can seriously degrade 31100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression. 31200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 31300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If deflate returns with avail_out == 0, this function must be called again 31400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with the same value of the flush parameter and more output space (updated 31500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes avail_out), until the flush is complete (deflate returns with non-zero 31600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that 31700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes avail_out is greater than six to avoid repeated flush markers due to 31800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes avail_out == 0 on return. 31900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 32000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the parameter flush is set to Z_FINISH, pending input is processed, 32100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes pending output is flushed and deflate returns with Z_STREAM_END if there was 32200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough output space; if deflate returns with Z_OK, this function must be 32300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes called again with Z_FINISH and more output space (updated avail_out) but no 32400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes more input data, until it returns with Z_STREAM_END or an error. After 32500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate has returned Z_STREAM_END, the only possible operations on the stream 32600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes are deflateReset or deflateEnd. 32700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 32800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_FINISH can be used immediately after deflateInit if all the compression 32900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is to be done in a single step. In this case, avail_out must be at least the 33000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes value returned by deflateBound (see below). Then deflate is guaranteed to 33100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes return Z_STREAM_END. If not enough output space is provided, deflate will 33200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes not return Z_STREAM_END, and it must be called again as described above. 33300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 33400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate() sets strm->adler to the adler32 checksum of all input read 33500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes so far (that is, total_in bytes). 33600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 33700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate() may update strm->data_type if it can make a good guess about 33800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered 33900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes binary. This field is only for information purposes and does not affect the 34000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression algorithm in any manner. 34100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 34200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate() returns Z_OK if some progress has been made (more input 34300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes processed or more output produced), Z_STREAM_END if all input has been 34400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes consumed and all output has been produced (only when flush is set to 34500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example 34600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible 34700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not 34800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fatal, and deflate() can be called again with more input and more output 34900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes space to continue compressing. 35000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 35100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 35200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 35300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); 35400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 35500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes All dynamically allocated data structures for this stream are freed. 35600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function discards any unprocessed input and does not flush any pending 35700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output. 35800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 35900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the 36000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent, Z_DATA_ERROR if the stream was freed 36100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes prematurely (some input or output was discarded). In the error case, msg 36200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes may be set but then points to a static string (which must not be 36300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deallocated). 36400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 36500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 36600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 36700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 36800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); 36900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 37000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Initializes the internal stream state for decompression. The fields 37100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes next_in, avail_in, zalloc, zfree and opaque must be initialized before by 37200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the caller. If next_in is not Z_NULL and avail_in is large enough (the 37300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes exact value depends on the compression method), inflateInit determines the 37400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression method from the zlib header and allocates all data structures 37500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes accordingly; otherwise the allocation will be deferred to the first call of 37600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to 37700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes use default allocation functions. 37800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 37900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 38000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 38100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes version assumed by the caller, or Z_STREAM_ERROR if the parameters are 38200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes invalid, such as a null pointer to the structure. msg is set to null if 38300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes there is no error message. inflateInit does not perform any decompression 38400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes apart from possibly reading the zlib header if present: actual decompression 38500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will be done by inflate(). (So next_in and avail_in may be modified, but 38600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes next_out and avail_out are unused and unchanged.) The current implementation 38700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of inflateInit() does not process any header information -- that is deferred 38800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes until inflate() is called. 38900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 39000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 39100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 39200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); 39300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 39400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate decompresses as much data as possible, and stops when the input 39500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer becomes empty or the output buffer becomes full. It may introduce 39600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes some output latency (reading input without producing any output) except when 39700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes forced to flush. 39800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 39900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The detailed semantics are as follows. inflate performs one or both of the 40000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes following actions: 40100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 40200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes - Decompress more input starting at next_in and update next_in and avail_in 40300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes accordingly. If not all input can be processed (because there is not 40400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough room in the output buffer), next_in is updated and processing will 40500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes resume at this point for the next call of inflate(). 40600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 40700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes - Provide more output starting at next_out and update next_out and avail_out 40800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes accordingly. inflate() provides as much output as possible, until there is 40900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes no more input data or no more space in the output buffer (see below about 41000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the flush parameter). 41100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 41200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Before the call of inflate(), the application should ensure that at least 41300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes one of the actions is possible, by providing more input and/or consuming more 41400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output, and updating the next_* and avail_* values accordingly. The 41500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes application can consume the uncompressed output when it wants, for example 41600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes when the output buffer is full (avail_out == 0), or after each call of 41700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate(). If inflate returns Z_OK and with zero avail_out, it must be 41800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes called again after making room in the output buffer because there might be 41900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes more output pending. 42000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 42100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH, 42200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much 42300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output as possible to the output buffer. Z_BLOCK requests that inflate() 42400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stop if and when it gets to the next deflate block boundary. When decoding 42500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the zlib or gzip format, this will cause inflate() to return immediately 42600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes after the header and before the first block. When doing a raw inflate, 42700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() will go ahead and process the first block, and will return when it 42800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gets to the end of that block, or when it runs out of data. 42900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 43000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The Z_BLOCK option assists in appending to or combining deflate streams. 43100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Also to assist in this, on return inflate() will set strm->data_type to the 43200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes number of unused bits in the last byte taken from strm->next_in, plus 64 if 43300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() is currently decoding the last block in the deflate stream, plus 43400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 128 if inflate() returned immediately after decoding an end-of-block code or 43500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decoding the complete header up to just before the first byte of the deflate 43600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream. The end-of-block will not be indicated until all of the uncompressed 43700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes data from that block has been written to strm->next_out. The number of 43800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unused bits may in general be greater than seven, except when bit 7 of 43900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes data_type is set, in which case the number of unused bits will be less than 44000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes eight. data_type is set as noted here every time inflate() returns for all 44100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes flush options, and so can be used to determine the amount of currently 44200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes consumed input in bits. 44300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 44400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The Z_TREES option behaves as Z_BLOCK does, but it also returns when the 44500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes end of each deflate block header is reached, before any actual data in that 44600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes block is decoded. This allows the caller to determine the length of the 44700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate block header for later use in random access within a deflate block. 44800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 256 is added to the value of strm->data_type when inflate() returns 44900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes immediately after reaching the end of the deflate block header. 45000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 45100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() should normally be called until it returns Z_STREAM_END or an 45200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes error. However if all decompression is to be performed in a single step (a 45300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes single call of inflate), the parameter flush should be set to Z_FINISH. In 45400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes this case all pending input is processed and all pending output is flushed; 45509eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes avail_out must be large enough to hold all of the uncompressed data for the 45609eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes operation to complete. (The size of the uncompressed data may have been 45709eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes saved by the compressor for this purpose.) The use of Z_FINISH is not 45809eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes required to perform an inflation in one step. However it may be used to 45909eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes inform inflate that a faster approach can be used for the single inflate() 46009eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes call. Z_FINISH also informs inflate to not maintain a sliding window if the 46109eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes stream completes, which reduces inflate's memory footprint. If the stream 46209eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes does not complete, either because not all of the stream is provided or not 46309eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes enough output space is provided, then a sliding window will be allocated and 46409eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes inflate() can be called again to continue the operation as if Z_NO_FLUSH had 46509eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes been used. 46600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 46700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes In this implementation, inflate() always flushes as much output as 46800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes possible to the output buffer, and always uses the faster approach on the 46900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes first call. So the effects of the flush parameter in this implementation are 47000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes on the return value of inflate() as noted below, when inflate() returns early 47100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of 47200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory for a sliding window when Z_FINISH is used. 47300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 47400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If a preset dictionary is needed after this call (see inflateSetDictionary 47500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes below), inflate sets strm->adler to the Adler-32 checksum of the dictionary 47600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes chosen by the compressor and returns Z_NEED_DICT; otherwise it sets 47700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes strm->adler to the Adler-32 checksum of all output produced so far (that is, 47800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described 47900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes below. At the end of the stream, inflate() checks that its computed adler32 48000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes checksum is equal to that saved by the compressor and returns Z_STREAM_END 48100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes only if the checksum is correct. 48200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 48300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() can decompress and check either zlib-wrapped or gzip-wrapped 48400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate data. The header type is detected automatically, if requested when 48500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes initializing with inflateInit2(). Any information contained in the gzip 48600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes header is not retained, so applications that need that information should 48700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes instead use raw inflate, see inflateInit2() below, or inflateBack() and 48800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes perform their own processing of the gzip header and trailer. When processing 48900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output 49000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes producted so far. The CRC-32 is checked against the gzip trailer. 49100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 49200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() returns Z_OK if some progress has been made (more input processed 49300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes or more output produced), Z_STREAM_END if the end of the compressed data has 49400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes been reached and all uncompressed output has been produced, Z_NEED_DICT if a 49500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes preset dictionary is needed at this point, Z_DATA_ERROR if the input data was 49600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes corrupted (input stream not conforming to the zlib format or incorrect check 49700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes value), Z_STREAM_ERROR if the stream structure was inconsistent (for example 49800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory, 49900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_BUF_ERROR if no progress is possible or if there was not enough room in the 50000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and 50100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate() can be called again with more input and more output space to 50200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes continue decompressing. If Z_DATA_ERROR is returned, the application may 50300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes then call inflateSync() to look for a good compression block if a partial 50400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes recovery of the data is desired. 50500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 50600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 50700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 50800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); 50900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 51000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes All dynamically allocated data structures for this stream are freed. 51100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function discards any unprocessed input and does not flush any pending 51200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output. 51300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 51400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state 51500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes was inconsistent. In the error case, msg may be set but then points to a 51600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes static string (which must not be deallocated). 51700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 51800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 51900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 52000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* Advanced functions */ 52100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 52200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 52300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The following functions are needed only in some special applications. 52400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 52500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 52600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 52700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, 52800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int level, 52900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int method, 53000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int windowBits, 53100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int memLevel, 53200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int strategy)); 53300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 53400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This is another version of deflateInit with more compression options. The 53500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fields next_in, zalloc, zfree and opaque must be initialized before by the 53600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes caller. 53700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 53800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The method parameter is the compression method. It must be Z_DEFLATED in 53900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes this version of the library. 54000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 54100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The windowBits parameter is the base two logarithm of the window size 54200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (the size of the history buffer). It should be in the range 8..15 for this 54300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes version of the library. Larger values of this parameter result in better 54400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression at the expense of memory usage. The default value is 15 if 54500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit is used instead. 54600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 54700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes windowBits can also be -8..-15 for raw deflate. In this case, -windowBits 54800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes determines the window size. deflate() will then generate raw deflate data 54900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with no zlib header or trailer, and will not compute an adler32 check value. 55000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 55100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes windowBits can also be greater than 15 for optional gzip encoding. Add 55200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 16 to windowBits to write a simple gzip header and trailer around the 55300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed data instead of a zlib wrapper. The gzip header will have no 55400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file name, no extra data, no comment, no modification time (set to zero), no 55500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes header crc, and the operating system will be set to 255 (unknown). If a 55600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip stream is being written, strm->adler is a crc32 instead of an adler32. 55700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 55800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The memLevel parameter specifies how much memory should be allocated 55900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for the internal compression state. memLevel=1 uses minimum memory but is 56000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes slow and reduces compression ratio; memLevel=9 uses maximum memory for 56100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes optimal speed. The default value is 8. See zconf.h for total memory usage 56200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes as a function of windowBits and memLevel. 56300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 56400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The strategy parameter is used to tune the compression algorithm. Use the 56500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a 56600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no 56700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes string match), or Z_RLE to limit match distances to one (run-length 56800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes encoding). Filtered data consists mostly of small values with a somewhat 56900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes random distribution. In this case, the compression algorithm is tuned to 57000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compress them better. The effect of Z_FILTERED is to force more Huffman 57100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes coding and less string matching; it is somewhat intermediate between 57200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as 57300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The 57400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes strategy parameter only affects the compression ratio but not the 57500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes correctness of the compressed output even if it is not set appropriately. 57600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler 57700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decoder for special applications. 57800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 57900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 58000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid 58100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is 58200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes incompatible with the version assumed by the caller (ZLIB_VERSION). msg is 58300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes set to null if there is no error message. deflateInit2 does not perform any 58400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression: this will be done by deflate(). 58500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 58600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 58700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, 58800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const Bytef *dictionary, 58900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt dictLength)); 59000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 59100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Initializes the compression dictionary from the given byte sequence 59200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes without producing any compressed output. When using the zlib format, this 59300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes function must be called immediately after deflateInit, deflateInit2 or 59400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateReset, and before any call of deflate. When doing raw deflate, this 59500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes function must be called either before any call of deflate, or immediately 59600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes after the completion of a deflate block, i.e. after all input has been 59700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes consumed and all output has been delivered when using any of the flush 59800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The 59900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressor and decompressor must use exactly the same dictionary (see 60000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateSetDictionary). 60100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 60200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The dictionary should consist of strings (byte sequences) that are likely 60300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to be encountered later in the data to be compressed, with the most commonly 60400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes used strings preferably put towards the end of the dictionary. Using a 60500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes dictionary is most useful when the data to be compressed is short and can be 60600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes predicted with good accuracy; the data can then be compressed better than 60700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes with the default empty dictionary. 60800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 60900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Depending on the size of the compression data structures selected by 61000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit or deflateInit2, a part of the dictionary may in effect be 61100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes discarded, for example if the dictionary is larger than the window size 61200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided in deflateInit or deflateInit2. Thus the strings most likely to be 61300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes useful should be put at the end of the dictionary, not at the front. In 61400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes addition, the current implementation of deflate will use at most the window 61500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes size minus 262 bytes of the provided dictionary. 61600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 61700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Upon return of this function, strm->adler is set to the adler32 value 61800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of the dictionary; the decompressor may later use this value to determine 61900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes which dictionary has been used by the compressor. (The adler32 value 62000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes applies to the whole dictionary even if only a subset of the dictionary is 62100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes actually used by the compressor.) If a raw deflate was requested, then the 62200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes adler32 value is not computed and strm->adler is not set. 62300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 62400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a 62500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is 62600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inconsistent (for example if deflate has already been called for this stream 62700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes or if not at a block boundary for raw deflate). deflateSetDictionary does 62800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes not perform any compression: this will be done by deflate(). 62900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 63000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 63100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, 63200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_streamp source)); 63300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 63400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Sets the destination stream as a complete copy of the source stream. 63500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 63600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function can be useful when several compression strategies will be 63700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes tried, for example when there are several ways of pre-processing the input 63800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes data with a filter. The streams that will be discarded should then be freed 63900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes by calling deflateEnd. Note that deflateCopy duplicates the internal 64000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression state which can be quite large, so this strategy is slow and can 64100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes consume lots of memory. 64200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 64300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 64400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 64500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (such as zalloc being Z_NULL). msg is left unchanged in both source and 64600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes destination. 64700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 64800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 64900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); 65000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 65100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function is equivalent to deflateEnd followed by deflateInit, 65200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes but does not free and reallocate all the internal compression state. The 65300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream will keep the same compression level and any other attributes that 65400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes may have been set by deflateInit2. 65500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 65600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 65700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent (such as zalloc or state being Z_NULL). 65800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 65900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 66000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, 66100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int level, 66200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int strategy)); 66300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 66400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Dynamically update the compression level and compression strategy. The 66500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes interpretation of level and strategy is as in deflateInit2. This can be 66600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes used to switch between compression and straight copy of the input data, or 66700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to switch to a different kind of input data requiring a different strategy. 66800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the compression level is changed, the input available so far is 66900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed with the old level (and may be flushed); the new level will take 67000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes effect only at the next call of deflate(). 67100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 67200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Before the call of deflateParams, the stream state must be set as for 67300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes a call of deflate(), since the currently available input may have to be 67400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed and flushed. In particular, strm->avail_out must be non-zero. 67500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 67600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source 67700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if 67800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes strm->avail_out was zero. 67900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 68000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 68100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, 68200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int good_length, 68300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int max_lazy, 68400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int nice_length, 68500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int max_chain)); 68600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 68700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Fine tune deflate's internal compression parameters. This should only be 68800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes used by someone who understands the algorithm used by zlib's deflate for 68900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes searching for the best matching string, and even then only by the most 69000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fanatic optimizer trying to squeeze out the last compressed bit for their 69100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes specific input data. Read the deflate.c source code for the meaning of the 69200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes max_lazy, good_length, nice_length, and max_chain parameters. 69300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 69400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateTune() can be called after deflateInit() or deflateInit2(), and 69500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. 69600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 69700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 69800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, 69900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong sourceLen)); 70000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 70100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateBound() returns an upper bound on the compressed size after 70200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflation of sourceLen bytes. It must be called after deflateInit() or 70300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit2(), and after deflateSetHeader(), if used. This would be used 70400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to allocate an output buffer for deflation in a single pass, and so would be 70500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes called before deflate(). If that first deflate() call is provided the 70600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes sourceLen input bytes, an output buffer allocated to the size returned by 70700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed 70800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to return Z_STREAM_END. Note that it is possible for the compressed size to 70900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes be larger than the value returned by deflateBound() if flush options other 71000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes than Z_FINISH or Z_NO_FLUSH are used. 71100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 71200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 71300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflatePending OF((z_streamp strm, 71400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unsigned *pending, 71500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int *bits)); 71600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 71700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflatePending() returns the number of bytes and bits of output that have 71800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes been generated, but not yet provided in the available output. The bytes not 71900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided would be due to the available output space having being consumed. 72000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The number of bits of output not provided are between 0 and 7, where they 72100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes await more bits to join them in order to fill out a full byte. If pending 72200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes or bits are Z_NULL, then those values are not set. 72300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 72400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source 72500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent. 72600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 72700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 72800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, 72900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int bits, 73000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int value)); 73100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 73200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflatePrime() inserts bits in the deflate output stream. The intent 73300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is that this function is used to start off the deflate output with the bits 73400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes leftover from a previous deflate stream when appending to it. As such, this 73500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes function can only be used for raw deflate, and must be used before the first 73600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate() call after a deflateInit2() or deflateReset(). bits must be less 73700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes than or equal to 16, and that many of the least significant bits of value 73800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will be inserted in the output. 73900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 74000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough 74100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the 74200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes source stream state was inconsistent. 74300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 74400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 74500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, 74600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gz_headerp head)); 74700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 74800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateSetHeader() provides gzip header information for when a gzip 74900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream is requested by deflateInit2(). deflateSetHeader() may be called 75000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes after deflateInit2() or deflateReset() and before the first call of 75100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate(). The text, time, os, extra field, name, and comment information 75200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in the provided gz_header structure are written to the gzip header (xflag is 75300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ignored -- the extra flags are set according to the compression level). The 75400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes caller must assure that, if not Z_NULL, name and comment are terminated with 75500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes a zero byte, and that if extra is not Z_NULL, that extra_len bytes are 75600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes available there. If hcrc is true, a gzip header crc is included. Note that 75700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the current versions of the command-line version of gzip (up through version 75800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1.3.x) do not support header crc's, and will report that it is a "multi-part 75900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip file" and give up. 76000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 76100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If deflateSetHeader is not used, the default gzip header has text false, 76200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the time set to zero, and os set to 255, with no extra, name, or comment 76300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fields. The gzip header is returned to the default state by deflateReset(). 76400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 76500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 76600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent. 76700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 76800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 76900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 77000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, 77100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int windowBits)); 77200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 77300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This is another version of inflateInit with an extra parameter. The 77400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fields next_in, avail_in, zalloc, zfree and opaque must be initialized 77500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes before by the caller. 77600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 77700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The windowBits parameter is the base two logarithm of the maximum window 77800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes size (the size of the history buffer). It should be in the range 8..15 for 77900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes this version of the library. The default value is 15 if inflateInit is used 78000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes instead. windowBits must be greater than or equal to the windowBits value 78100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided to deflateInit2() while compressing, or it must be equal to 15 if 78200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit2() was not used. If a compressed stream with a larger window 78300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes size is given as input, inflate() will return with the error code 78400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_DATA_ERROR instead of trying to allocate a larger window. 78500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 78600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes windowBits can also be zero to request that inflate use the window size in 78700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the zlib header of the compressed stream. 78800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 78900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes windowBits can also be -8..-15 for raw inflate. In this case, -windowBits 79000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes determines the window size. inflate() will then process raw deflate data, 79100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes not looking for a zlib or gzip header, not generating a check value, and not 79200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes looking for any check values for comparison at the end of the stream. This 79300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is for use with other formats that use the deflate compressed data format 79400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes such as zip. Those formats provide their own check values. If a custom 79500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes format is developed using the raw deflate format for compressed data, it is 79600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes recommended that a check value such as an adler32 or a crc32 be applied to 79700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the uncompressed data as is done in the zlib, gzip, and zip formats. For 79800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes most applications, the zlib format should be used as is. Note that comments 79900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes above on the use in deflateInit2() applies to the magnitude of windowBits. 80000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 80100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes windowBits can also be greater than 15 for optional gzip decoding. Add 80200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 32 to windowBits to enable zlib and gzip decoding with automatic header 80300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes detection, or add 16 to decode only the gzip format (the zlib format will 80400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a 80500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes crc32 instead of an adler32. 80600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 80700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 80800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 80900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes version assumed by the caller, or Z_STREAM_ERROR if the parameters are 81000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes invalid, such as a null pointer to the structure. msg is set to null if 81100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes there is no error message. inflateInit2 does not perform any decompression 81200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes apart from possibly reading the zlib header if present: actual decompression 81300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will be done by inflate(). (So next_in and avail_in may be modified, but 81400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes next_out and avail_out are unused and unchanged.) The current implementation 81500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of inflateInit2() does not process any header information -- that is 81600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deferred until inflate() is called. 81700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 81800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 81900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, 82000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const Bytef *dictionary, 82100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uInt dictLength)); 82200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 82300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Initializes the decompression dictionary from the given uncompressed byte 82400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes sequence. This function must be called immediately after a call of inflate, 82500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if that call returned Z_NEED_DICT. The dictionary chosen by the compressor 82600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes can be determined from the adler32 value returned by that call of inflate. 82700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The compressor and decompressor must use exactly the same dictionary (see 82800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateSetDictionary). For raw inflate, this function can be called at any 82900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes time to set the dictionary. If the provided dictionary is smaller than the 83000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes window and there is already data in the window, then the provided dictionary 83100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will amend what's there. The application must insure that the dictionary 83200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that was used for compression is provided. 83300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 83400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a 83500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is 83600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the 83700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes expected one (incorrect adler32 value). inflateSetDictionary does not 83800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes perform any decompression: this will be done by subsequent calls of 83900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflate(). 84000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 84100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 84200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); 84300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 84400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Skips invalid compressed data until a possible full flush point (see above 84500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for the description of deflate with Z_FULL_FLUSH) can be found, or until all 84600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes available input is skipped. No output is provided. 84700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 84800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateSync searches for a 00 00 FF FF pattern in the compressed data. 84900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes All full flush points have this pattern, but not all occurences of this 85000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes pattern are full flush points. 85100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 85200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateSync returns Z_OK if a possible full flush point has been found, 85300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point 85400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes has been found, or Z_STREAM_ERROR if the stream structure was inconsistent. 85500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes In the success case, the application may save the current current value of 85600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes total_in which indicates where valid compressed data was found. In the 85700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes error case, the application may repeatedly call inflateSync, providing more 85800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes input each time, until success or end of the input data. 85900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 86000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 86100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, 86200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_streamp source)); 86300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 86400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Sets the destination stream as a complete copy of the source stream. 86500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 86600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function can be useful when randomly accessing a large stream. The 86700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes first pass through the stream can periodically record the inflate state, 86800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes allowing restarting inflate at those points when randomly accessing the 86900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream. 87000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 87100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 87200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 87300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (such as zalloc being Z_NULL). msg is left unchanged in both source and 87400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes destination. 87500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 87600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 87700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); 87800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 87900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function is equivalent to inflateEnd followed by inflateInit, 88000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes but does not free and reallocate all the internal decompression state. The 88100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream will keep attributes that may have been set by inflateInit2. 88200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 88300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 88400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent (such as zalloc or state being Z_NULL). 88500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 88600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 88700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, 88800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int windowBits)); 88900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 89000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function is the same as inflateReset, but it also permits changing 89100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the wrap and window size requests. The windowBits parameter is interpreted 89200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the same as it is for inflateInit2. 89300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 89400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source 89500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent (such as zalloc or state being Z_NULL), or if 89600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the windowBits parameter is invalid. 89700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 89800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 89900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, 90000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int bits, 90100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int value)); 90200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 90300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function inserts bits in the inflate input stream. The intent is 90400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that this function is used to start inflating at a bit position in the 90500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes middle of a byte. The provided bits will be used before any bytes are used 90600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes from next_in. This function should only be used with raw inflate, and 90700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes should be used before the first inflate() call after inflateInit2() or 90800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateReset(). bits must be less than or equal to 16, and that many of the 90900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes least significant bits of value will be inserted in the input. 91000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 91100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If bits is negative, then the input stream bit buffer is emptied. Then 91200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflatePrime() can be called again to put bits in the buffer. This is used 91300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to clear out bits leftover after feeding inflate a block description prior 91400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to feeding inflate codes. 91500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 91600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source 91700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent. 91800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 91900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 92000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); 92100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 92200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This function returns two values, one in the lower 16 bits of the return 92300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes value, and the other in the remaining upper bits, obtained by shifting the 92400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes return value down 16 bits. If the upper value is -1 and the lower value is 92500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zero, then inflate() is currently decoding information outside of a block. 92600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the upper value is -1 and the lower value is non-zero, then inflate is in 92700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the middle of a stored block, with the lower value equaling the number of 92800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes bytes from the input remaining to copy. If the upper value is not -1, then 92900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes it is the number of bits back from the current bit position in the input of 93000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the code (literal or length/distance pair) currently being processed. In 93100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that case the lower value is the number of bytes already emitted for that 93200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes code. 93300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 93400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes A code is being processed if inflate is waiting for more input to complete 93500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decoding of the code, or if it has completed decoding but is waiting for 93600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes more output space to write the literal or match data. 93700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 93800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateMark() is used to mark locations in the input data for random 93900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes access, which may be at bit positions, and to note those cases where the 94000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output of a code may span boundaries of random access blocks. The current 94100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes location in the input stream can be determined from avail_in and data_type 94200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes as noted in the description for the Z_BLOCK flush parameter for inflate. 94300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 94400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateMark returns the value noted above or -1 << 16 if the provided 94500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes source stream state was inconsistent. 94600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 94700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 94800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, 94900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gz_headerp head)); 95000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 95100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateGetHeader() requests that gzip header information be stored in the 95200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided gz_header structure. inflateGetHeader() may be called after 95300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateInit2() or inflateReset(), and before the first call of inflate(). 95400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes As inflate() processes the gzip stream, head->done is zero until the header 95500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is completed, at which time head->done is set to one. If a zlib stream is 95600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes being decoded, then head->done is set to -1 to indicate that there will be 95700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be 95800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes used to force inflate() to return immediately after header processing is 95900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes complete and before any actual data is decompressed. 96000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 96100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The text, time, xflags, and os fields are filled in with the gzip header 96200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes contents. hcrc is set to true if there is a header CRC. (The header CRC 96300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes was valid if done is set to one.) If extra is not Z_NULL, then extra_max 96400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes contains the maximum number of bytes to write to extra. Once done is true, 96500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes extra_len contains the actual extra field length, and extra contains the 96600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes extra field, or that field truncated if extra_max is less than extra_len. 96700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If name is not Z_NULL, then up to name_max characters are written there, 96800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes terminated with a zero unless the length is greater than name_max. If 96900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes comment is not Z_NULL, then up to comm_max characters are written there, 97000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes terminated with a zero unless the length is greater than comm_max. When any 97100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of extra, name, or comment are not Z_NULL and the respective field is not 97200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes present in the header, then that field is set to Z_NULL to signal its 97300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes absence. This allows the use of deflateSetHeader() with the returned 97400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes structure to duplicate the header. However if those fields are set to 97500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes allocated memory, then the application will need to save those pointers 97600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes elsewhere so that they can be eventually freed. 97700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 97800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If inflateGetHeader is not used, then the header information is simply 97900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes discarded. The header is always checked for validity, including the header 98000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes CRC if present. inflateReset() will reset the process to discard the header 98100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes information. The application would need to call inflateGetHeader() again to 98200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes retrieve the header from the next gzip stream. 98300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 98400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 98500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream state was inconsistent. 98600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 98700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 98800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 98900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, 99000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unsigned char FAR *window)); 99100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 99200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Initialize the internal stream state for decompression using inflateBack() 99300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes calls. The fields zalloc, zfree and opaque in strm must be initialized 99400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes before the call. If zalloc and zfree are Z_NULL, then the default library- 99500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes derived memory allocation routines are used. windowBits is the base two 99600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes logarithm of the window size, in the range 8..15. window is a caller 99700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes supplied buffer of that size. Except for special applications where it is 99800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes assured that deflate was used with small window sizes, windowBits must be 15 99900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes and a 32K byte window must be supplied to be able to decompress general 100000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate streams. 100100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 100200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes See inflateBack() for the usage of these routines. 100300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 100400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of 100500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the parameters are invalid, Z_MEM_ERROR if the internal state could not be 100600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes allocated, or Z_VERSION_ERROR if the version of the library does not match 100700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the version of the header file. 100800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 100900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 101000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); 101100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); 101200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 101300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, 101400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in_func in, void FAR *in_desc, 101500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes out_func out, void FAR *out_desc)); 101600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 101700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBack() does a raw inflate with a single call using a call-back 101800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes interface for input and output. This is more efficient than inflate() for 101900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file i/o applications in that it avoids copying between the output and the 102000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes sliding window by simply making the window itself the output buffer. This 102100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes function trusts the application to not change the output buffer passed by 102200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the output function, at least until inflateBack() returns. 102300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 102400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBackInit() must be called first to allocate the internal state 102500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes and to initialize the state with the user-provided window buffer. 102600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBack() may then be used multiple times to inflate a complete, raw 102700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate stream with each call. inflateBackEnd() is then called to free the 102800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes allocated state. 102900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 103000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes A raw deflate stream is one with no zlib or gzip header or trailer. 103100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This routine would normally be used in a utility that reads zip or gzip 103200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes files and writes out uncompressed files. The utility would decode the 103300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes header and process the trailer on its own, hence this routine expects only 103400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the raw deflate stream to decompress. This is different from the normal 103500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes behavior of inflate(), which expects either a zlib or gzip header and 103600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes trailer around the deflate stream. 103700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 103800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBack() uses two subroutines supplied by the caller that are then 103900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes called by inflateBack() for input and output. inflateBack() calls those 104000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes routines until it reads a complete deflate stream and writes out all of the 104100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed data, or until it encounters an error. The function's 104200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes parameters and return types are defined above in the in_func and out_func 104300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes typedefs. inflateBack() will call in(in_desc, &buf) which should return the 104400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes number of bytes of provided input, and a pointer to that input in buf. If 104500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes there is no input available, in() must return zero--buf is ignored in that 104600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes case--and inflateBack() will return a buffer error. inflateBack() will call 104700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() 104800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes should return zero on success, or non-zero on failure. If out() returns 104900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes non-zero, inflateBack() will return with an error. Neither in() nor out() 105000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes are permitted to change the contents of the window provided to 105100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBackInit(), which is also the buffer that out() uses to write from. 105200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The length written by out() will be at most the window size. Any non-zero 105300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes amount of input may be provided by in(). 105400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 105500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes For convenience, inflateBack() can be provided input on the first call by 105600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes setting strm->next_in and strm->avail_in. If that input is exhausted, then 105700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in() will be called. Therefore strm->next_in must be initialized before 105800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called 105900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in 106000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes must also be initialized, and then if strm->avail_in is not zero, input will 106100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes initially be taken from strm->next_in[0 .. strm->avail_in - 1]. 106200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 106300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The in_desc and out_desc parameters of inflateBack() is passed as the 106400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes first parameter of in() and out() respectively when they are called. These 106500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes descriptors can be optionally used to pass any information that the caller- 106600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes supplied in() and out() functions need to do their job. 106700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 106800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes On return, inflateBack() will set strm->next_in and strm->avail_in to 106900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes pass back any unused input that was provided by the last in() call. The 107000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR 107100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if in() or out() returned an error, Z_DATA_ERROR if there was a format error 107200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in the deflate stream (in which case strm->msg is set to indicate the nature 107300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of the error), or Z_STREAM_ERROR if the stream was not properly initialized. 107400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes In the case of Z_BUF_ERROR, an input or output error can be distinguished 107500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes using strm->next_in which will be Z_NULL only if in() returned an error. If 107600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning 107700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes non-zero. (in() will always be called before out(), so strm->next_in is 107800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes assured to be defined if out() returns non-zero.) Note that inflateBack() 107900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes cannot return Z_OK. 108000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 108100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 108200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); 108300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 108400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes All memory allocated by inflateBackInit() is freed. 108500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 108600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream 108700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes state was inconsistent. 108800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 108900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 109000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); 109100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* Return flags indicating compile-time options. 109200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 109300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: 109400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 1.0: size of uInt 109500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 3.2: size of uLong 109600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 5.4: size of voidpf (pointer) 109700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 7.6: size of z_off_t 109800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 109900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Compiler, assembler, and debug options: 110000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 8: DEBUG 110100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 9: ASMV or ASMINF -- use ASM code 110200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention 110300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 11: 0 (reserved) 110400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 110500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes One-time table building (smaller code, but not thread-safe if true): 110600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 12: BUILDFIXED -- build static block decoding tables when needed 110700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed 110800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 14,15: 0 (reserved) 110900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 111000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Library content (indicates missing functionality): 111100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking 111200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflate code when not needed) 111300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect 111400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes and decode gzip streams (to avoid linking crc code) 111500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 18-19: 0 (reserved) 111600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 111700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Operation variations (changes in library functionality): 111800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate 111900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 21: FASTEST -- deflate algorithm with only one, lowest compression level 112000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 22,23: 0 (reserved) 112100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 112200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The sprintf variant used by gzprintf (zero is best): 112300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format 112400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! 112500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 26: 0 = returns value, 1 = void -- 1 means inferred string length returned 112600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 112700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Remainder: 112800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 27-31: 0 (reserved) 112900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 113000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 113100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#ifndef Z_SOLO 113200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 113300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* utility functions */ 113400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 113500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 113600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The following utility functions are implemented on top of the basic 113700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream-oriented functions. To simplify the interface, some default options 113800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes are assumed (compression level and memory usage, standard memory allocation 113900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes functions). The source code of these utility functions can be modified if 114000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes you need special options. 114100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 114200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 114300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, 114400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const Bytef *source, uLong sourceLen)); 114500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 114600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Compresses the source buffer into the destination buffer. sourceLen is 114700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the byte length of the source buffer. Upon entry, destLen is the total size 114800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of the destination buffer, which must be at least the value returned by 114900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressBound(sourceLen). Upon exit, destLen is the actual size of the 115000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed buffer. 115100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 115200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compress returns Z_OK if success, Z_MEM_ERROR if there was not 115300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough memory, Z_BUF_ERROR if there was not enough room in the output 115400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer. 115500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 115600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 115700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen, 115800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const Bytef *source, uLong sourceLen, 115900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int level)); 116000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 116100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Compresses the source buffer into the destination buffer. The level 116200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes parameter has the same meaning as in deflateInit. sourceLen is the byte 116300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes length of the source buffer. Upon entry, destLen is the total size of the 116400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes destination buffer, which must be at least the value returned by 116500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressBound(sourceLen). Upon exit, destLen is the actual size of the 116600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed buffer. 116700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 116800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 116900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes memory, Z_BUF_ERROR if there was not enough room in the output buffer, 117000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_STREAM_ERROR if the level parameter is invalid. 117100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 117200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 117300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); 117400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 117500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressBound() returns an upper bound on the compressed size after 117600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compress() or compress2() on sourceLen bytes. It would be used before a 117700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compress() or compress2() call to allocate the destination buffer. 117800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 117900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 118000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, 118100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const Bytef *source, uLong sourceLen)); 118200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 118300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Decompresses the source buffer into the destination buffer. sourceLen is 118400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the byte length of the source buffer. Upon entry, destLen is the total size 118500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of the destination buffer, which must be large enough to hold the entire 118600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed data. (The size of the uncompressed data must have been saved 118700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes previously by the compressor and transmitted to the decompressor by some 118800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes mechanism outside the scope of this compression library.) Upon exit, destLen 118900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is the actual size of the uncompressed buffer. 119000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 119100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompress returns Z_OK if success, Z_MEM_ERROR if there was not 119200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes enough memory, Z_BUF_ERROR if there was not enough room in the output 119300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In 119400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the case where there is not enough room, uncompress() will fill the output 119500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buffer with the uncompressed data up to that point. 119600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 119700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 119800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* gzip file access functions */ 119900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 120000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 120100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes This library supports reading and writing files in gzip (.gz) format with 120200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes an interface similar to that of stdio, using the functions that start with 120300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes "gz". The gzip format is different from the zlib format. gzip is a gzip 120400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes wrapper, documented in RFC 1952, wrapped around a deflate stream. 120500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 120600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 120700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughestypedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */ 120800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 120900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 121000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); 121100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 121200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Opens a gzip (.gz) file for reading or writing. The mode parameter is as 121300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in fopen ("rb" or "wb") but can also include a compression level ("wb9") or 121400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only 121500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F' 121600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for fixed code compression as in "wb9F". (See the description of 121700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit2 for more information about the strategy parameter.) 'T' will 121800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes request transparent writing or appending with no compression and not using 121900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the gzip format. 122000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 122100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes "a" can be used instead of "w" to request that the gzip stream that will 122200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes be written be appended to the file. "+" will result in an error, since 122309eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes reading and writing to the same gzip file is not supported. The addition of 122409eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes "x" when writing will create the file exclusively, which fails if the file 122509eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes already exists. On systems that support it, the addition of "e" when 122609eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes reading or writing will set the flag to close the file on an execve() call. 122700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 122800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes These functions, as well as gzip, will read and decode a sequence of gzip 122900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes streams in a file. The append function of gzopen() can be used to create 123000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes such a file. (Also see gzflush() for another way to do this.) When 123100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes appending, gzopen does not test whether the file begins with a gzip stream, 123200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes nor does it look for the end of the gzip streams to begin appending. gzopen 123300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will simply append a gzip stream to the existing file. 123400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 123500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzopen can be used to read a file which is not in gzip format; in this 123600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes case gzread will directly read from the file without decompression. When 123700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes reading, this will be detected automatically by looking for the magic two- 123800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes byte gzip header. 123900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 124000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzopen returns NULL if the file could not be opened, if there was 124100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes insufficient memory to allocate the gzFile state, or if an invalid mode was 124200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes specified (an 'r', 'w', or 'a' was not provided, or '+' was provided). 124300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes errno can be checked to determine if the reason gzopen failed was that the 124400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file could not be opened. 124500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 124600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 124700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); 124800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 124900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzdopen associates a gzFile with the file descriptor fd. File descriptors 125000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes are obtained from calls like open, dup, creat, pipe or fileno (if the file 125100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes has been previously opened with fopen). The mode parameter is as in gzopen. 125200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 125300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The next call of gzclose on the returned gzFile will also close the file 125400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor 125500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd, 125600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes mode);. The duplicated descriptor should be saved to avoid a leak, since 125700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzdopen does not close fd if it fails. If you are using fileno() to get the 125800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file descriptor from a FILE *, then you will have to use dup() to avoid 125900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes double-close()ing the file descriptor. Both gzclose() and fclose() will 126000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes close the associated file descriptor, so they need to have different file 126100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes descriptors. 126200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 126300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzdopen returns NULL if there was insufficient memory to allocate the 126400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not 126500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes provided, or '+' was provided), or if fd is -1. The file descriptor is not 126600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes used until the next gz* read, write, seek, or close operation, so gzdopen 126700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will not detect if fd is invalid (unless fd is -1). 126800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 126900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 127000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); 127100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 127200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Set the internal buffer size used by this library's functions. The 127300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes default buffer size is 8192 bytes. This function must be called after 127400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzopen() or gzdopen(), and before any other calls that read or write the 127500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file. The buffer memory allocation is always deferred to the first read or 127600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes write. Two buffers are allocated, either both of the specified size when 127700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes writing, or one of the specified size and the other twice that size when 127800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes reading. A larger buffer size of, for example, 64K or 128K bytes will 127900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes noticeably increase the speed of decompression (reading). 128000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 128100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The new buffer size also affects the maximum length for gzprintf(). 128200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 128300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzbuffer() returns 0 on success, or -1 on failure, such as being called 128400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes too late. 128500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 128600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 128700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); 128800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 128900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Dynamically update the compression level or strategy. See the description 129000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of deflateInit2 for the meaning of these parameters. 129100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 129200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not 129300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes opened for writing. 129400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 129500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 129600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); 129700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 129800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Reads the given number of uncompressed bytes from the compressed file. If 129900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the input file is not in gzip format, gzread copies the given number of 130000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes bytes into the buffer directly from the file. 130100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 130200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes After reaching the end of a gzip stream in the input, gzread will continue 130300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to read, looking for another gzip stream. Any number of gzip streams may be 130400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes concatenated in the input file, and will all be decompressed by gzread(). 130500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If something other than a gzip stream is encountered after a gzip stream, 130600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that remaining trailing garbage is ignored (and no error is returned). 130700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 130800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzread can be used to read a gzip file that is being concurrently written. 130900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Upon reaching the end of the input, gzread will return with the available 131000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then 131100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzclearerr can be used to clear the end of file indicator in order to permit 131200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzread to be tried again. Z_OK indicates that a gzip stream was completed 131300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes on the last gzread. Z_BUF_ERROR indicates that the input file ended in the 131400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes middle of a gzip stream. Note that gzread does not return -1 in the event 131500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes of an incomplete gzip stream. This error is deferred until gzclose(), which 131600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip 131700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes stream. Alternatively, gzerror can be used before gzclose to detect this 131800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes case. 131900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 132000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzread returns the number of uncompressed bytes actually read, less than 132100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes len for end of file, or -1 for error. 132200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 132300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 132400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzwrite OF((gzFile file, 132500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes voidpc buf, unsigned len)); 132600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 132700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Writes the given number of uncompressed bytes into the compressed file. 132800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzwrite returns the number of uncompressed bytes written or 0 in case of 132900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes error. 133000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 133100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 133200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...)); 133300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 133400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Converts, formats, and writes the arguments to the compressed file under 133500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes control of the format string, as in fprintf. gzprintf returns the number of 133600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed bytes actually written, or 0 in case of error. The number of 133700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed bytes written is limited to 8191, or one less than the buffer 133800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes size given to gzbuffer(). The caller should assure that this limit is not 133900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes exceeded. If it is exceeded, then gzprintf() will return an error (0) with 134000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes nothing written. In this case, there may also be a buffer overflow with 134100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unpredictable consequences, which is possible only if zlib was compiled with 134200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the insecure functions sprintf() or vsprintf() because the secure snprintf() 134300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes or vsnprintf() functions were not available. This can be determined using 134400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zlibCompileFlags(). 134500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 134600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 134700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); 134800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 134900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Writes the given null-terminated string to the compressed file, excluding 135000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the terminating null character. 135100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 135200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzputs returns the number of characters written, or -1 in case of error. 135300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 135400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 135500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); 135600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 135700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Reads bytes from the compressed file until len-1 characters are read, or a 135800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes newline character is read and transferred to buf, or an end-of-file 135900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes condition is encountered. If any characters are read or if len == 1, the 136000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes string is terminated with a null character. If no characters are read due 136100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes to an end-of-file or len < 1, then the buffer is left untouched. 136200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 136300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzgets returns buf which is a null-terminated string, or it returns NULL 136400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for end-of-file or in case of error. If there was an error, the contents at 136500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes buf are indeterminate. 136600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 136700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 136800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); 136900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 137000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Writes c, converted to an unsigned char, into the compressed file. gzputc 137100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes returns the value that was written, or -1 in case of error. 137200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 137300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 137400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzgetc OF((gzFile file)); 137500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 137600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Reads one byte from the compressed file. gzgetc returns this byte or -1 137700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in case of end of file or error. This is implemented as a macro for speed. 137800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes As such, it does not do all of the checking the other functions do. I.e. 137900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes it does not check to see if file is NULL, nor whether the structure file 138000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes points to has been clobbered or not. 138100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 138200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 138300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); 138400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 138500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Push one character back onto the stream to be read as the first character 138600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes on the next read. At least one character of push-back is allowed. 138700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzungetc() returns the character pushed, or -1 on failure. gzungetc() will 138800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes fail if c is -1, and may fail if a character has been pushed but not read 138900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes yet. If gzungetc is used immediately after gzopen or gzdopen, at least the 139000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes output buffer size of pushed characters is allowed. (See gzbuffer above.) 139100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The pushed character will be discarded if the stream is repositioned with 139200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzseek() or gzrewind(). 139300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 139400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 139500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); 139600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 139700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Flushes all pending output into the compressed file. The parameter flush 139800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is as in the deflate() function. The return value is the zlib error number 139900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (see function gzerror below). gzflush is only permitted when writing. 140000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 140100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the flush parameter is Z_FINISH, the remaining data is written and the 140200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip stream is completed in the output. If gzwrite() is called again, a new 140300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip stream will be started in the output. gzread() is able to read such 140400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes concatented gzip streams. 140500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 140600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzflush should be called only when strictly necessary because it will 140700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes degrade compression if called too often. 140800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 140900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 141000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 141100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, 141200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_off_t offset, int whence)); 141300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 141400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Sets the starting position for the next gzread or gzwrite on the given 141500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed file. The offset represents a number of bytes in the 141600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed data stream. The whence parameter is defined as in lseek(2); 141700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the value SEEK_END is not supported. 141800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 141900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the file is opened for reading, this function is emulated but can be 142000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes extremely slow. If the file is opened for writing, only forward seeks are 142100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes supported; gzseek then compresses a sequence of zeroes up to the new 142200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes starting position. 142300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 142400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzseek returns the resulting offset location as measured in bytes from 142500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes the beginning of the uncompressed stream, or -1 in case of error, in 142600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes particular if the file is opened for writing and the new starting position 142700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes would be before the current position. 142800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 142900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 143000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzrewind OF((gzFile file)); 143100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 143200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Rewinds the given file. This function is supported only for reading. 143300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 143400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) 143500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 143600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 143700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 143800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); 143900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 144000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Returns the starting position for the next gzread or gzwrite on the given 144100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed file. This position represents a number of bytes in the 144200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uncompressed data stream, and is zero when starting, even if appending or 144300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes reading a gzip stream from the middle of a file using gzdopen(). 144400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 144500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) 144600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 144700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 144800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 144900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); 145000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 145100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Returns the current offset in the file being read or written. This offset 145200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes includes the count of bytes that precede the gzip stream, for example when 145300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes appending or when using gzdopen() for reading. When reading, the offset 145400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes does not include as yet unused buffered input. This information can be used 145500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes for a progress indicator. On error, gzoffset() returns -1. 145600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 145700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 145800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzeof OF((gzFile file)); 145900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 146000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Returns true (1) if the end-of-file indicator has been set while reading, 146100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes false (0) otherwise. Note that the end-of-file indicator is set only if the 146200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes read tried to go past the end of the input, but came up short. Therefore, 146300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes just like feof(), gzeof() may return false even if there is no more data to 146400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes read, in the event that the last read request was for the exact number of 146500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes bytes remaining in the input file. This will happen if the input file size 146600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is an exact multiple of the buffer size. 146700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 146800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If gzeof() returns true, then the read functions will return no more data, 146900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unless the end-of-file indicator is reset by gzclearerr() and the input file 147000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes has grown since the previous end of file was detected. 147100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 147200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 147300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzdirect OF((gzFile file)); 147400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 147500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Returns true (1) if file is being copied directly while reading, or false 147600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (0) if file is a gzip stream being decompressed. 147700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 147800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If the input file is empty, gzdirect() will return true, since the input 147900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes does not contain a gzip stream. 148000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 148100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes If gzdirect() is used immediately after gzopen() or gzdopen() it will 148200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes cause buffers to be allocated to allow reading the file to determine if it 148300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes is a gzip file. Therefore if gzbuffer() is used, it should be called before 148400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzdirect(). 148500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 148600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes When writing, gzdirect() returns true (1) if transparent writing was 148700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note: 148800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzdirect() is not needed when writing. Transparent writing must be 148900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes explicitly requested, so the application already knows the answer. When 149000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes linking statically, using gzdirect() will include all of the zlib code for 149100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzip file reading and decompression, which may not be desired.) 149200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 149300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 149400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzclose OF((gzFile file)); 149500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 149600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Flushes all pending output if necessary, closes the compressed file and 149700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deallocates the (de)compression state. Note that once file is closed, you 149800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes cannot call gzerror with file, since its structures have been deallocated. 149900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzclose must not be called more than once on the same file, just as free 150000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes must not be called more than once on the same allocation. 150100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 150200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a 150300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the 150400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes last read ended in the middle of a gzip stream, or Z_OK on success. 150500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 150600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 150700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzclose_r OF((gzFile file)); 150800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); 150900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 151000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Same as gzclose(), but gzclose_r() is only for use when reading, and 151100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzclose_w() is only for use when writing or appending. The advantage to 151200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes using these instead of gzclose() is that they avoid linking in zlib 151300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compression or decompression code that is not used when only reading or only 151400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes writing respectively. If gzclose() is used, then both compression and 151500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes decompression code will be included the application when linking to a static 151600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes zlib library. 151700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 151800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 151900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); 152000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 152100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Returns the error message for the last error which occurred on the given 152200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes compressed file. errnum is set to zlib error number. If an error occurred 152300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes in the file system and not in the compression library, errnum is set to 152400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Z_ERRNO and the application may consult errno to get the exact error code. 152500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 152600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes The application must not modify the returned string. Future calls to 152700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes this function may invalidate the previously returned string. If file is 152800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes closed, then the string previously returned by gzerror will no longer be 152900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes available. 153000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 153100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes gzerror() should be used to distinguish errors from end-of-file for those 153200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes functions above that do not distinguish those cases in their return values. 153300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 153400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 153500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); 153600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 153700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Clears the error and end-of-file flags for file. This is analogous to the 153800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes clearerr() function in stdio. This is useful for continuing to read a gzip 153900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes file that is being written concurrently. 154000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 154100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 154200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif /* !Z_SOLO */ 154300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 154400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* checksum functions */ 154500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 154600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 154700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes These functions are not related to compression but are exported 154800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes anyway because they might be useful in applications using the compression 154900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes library. 155000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 155100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 155200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); 155300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 155400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Update a running Adler-32 checksum with the bytes buf[0..len-1] and 155500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes return the updated checksum. If buf is Z_NULL, this function returns the 155600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes required initial value for the checksum. 155700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 155800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes An Adler-32 checksum is almost as reliable as a CRC32 but can be computed 155900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes much faster. 156000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 156100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Usage example: 156200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 156300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong adler = adler32(0L, Z_NULL, 0); 156400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 156500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes while (read_buffer(buffer, length) != EOF) { 156600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes adler = adler32(adler, buffer, length); 156700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes } 156800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if (adler != original_adler) error(); 156900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 157000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 157100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 157200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, 157300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_off_t len2)); 157400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 157500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 157600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for 157700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of 157800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note 157900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes that the z_off_t type (like off_t) is a signed integer. If len2 is 158000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes negative, the result has no meaning or utility. 158100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 158200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 158300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); 158400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 158500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Update a running CRC-32 with the bytes buf[0..len-1] and return the 158600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes updated CRC-32. If buf is Z_NULL, this function returns the required 158709eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes initial value for the crc. Pre- and post-conditioning (one's complement) is 158809eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes performed within this function so it shouldn't be done by the application. 158900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 159000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Usage example: 159100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 159200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes uLong crc = crc32(0L, Z_NULL, 0); 159300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 159400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes while (read_buffer(buffer, length) != EOF) { 159500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes crc = crc32(crc, buffer, length); 159600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes } 159700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes if (crc != original_crc) error(); 159800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 159900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 160000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* 160100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); 160200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 160300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes Combine two CRC-32 check values into one. For two sequences of bytes, 160400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes seq1 and seq2 with lengths len1 and len2, CRC-32 check values were 160500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 160600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and 160700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes len2. 160800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes*/ 160900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 161000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 161100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes /* various hacks, don't look :) */ 161200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 161300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* deflateInit and inflateInit are macros to allow checking the zlib version 161400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * and the compiler's view of z_stream: 161500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 161600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, 161700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const char *version, int stream_size)); 161800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, 161900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const char *version, int stream_size)); 162000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, 162100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int windowBits, int memLevel, 162200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int strategy, const char *version, 162300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int stream_size)); 162400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, 162500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const char *version, int stream_size)); 162600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, 162700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unsigned char FAR *window, 162800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes const char *version, 162900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes int stream_size)); 163000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define deflateInit(strm, level) \ 163100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) 163200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define inflateInit(strm) \ 163300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream)) 163400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ 163500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ 163600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (strategy), ZLIB_VERSION, (int)sizeof(z_stream)) 163700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define inflateInit2(strm, windowBits) \ 163800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateInit2_((strm), (windowBits), ZLIB_VERSION, \ 163900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes (int)sizeof(z_stream)) 164000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#define inflateBackInit(strm, windowBits, window) \ 164100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes inflateBackInit_((strm), (windowBits), (window), \ 164200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZLIB_VERSION, (int)sizeof(z_stream)) 164300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 164400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#ifndef Z_SOLO 164500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 164600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* gzgetc() macro and its supporting function and exposed data structure. Note 164700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * that the real internal state is much larger than the exposed structure. 164800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * This abbreviated structure exposes just enough for the gzgetc() macro. The 164900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * user should not mess with these exposed elements, since their names or 165000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * behavior could change in the future, perhaps even capriciously. They can 165100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * only be used by the gzgetc() macro. You have been warned. 165200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 165300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughesstruct gzFile_s { 165400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unsigned have; 165500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes unsigned char *next; 165600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes z_off64_t pos; 165700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes}; 165809eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott HughesZEXTERN int ZEXPORT gzgetc_ OF((gzFile file)); /* backward compatibility */ 165909eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#ifdef Z_PREFIX_SET 166009eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes# undef z_gzgetc 166109eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes# define z_gzgetc(g) \ 166209eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g)) 166309eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#else 166409eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes# define gzgetc(g) \ 166509eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g)) 166609eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#endif 166700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 166800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or 166900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if 167000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * both are true, the application gets the *64 functions, and the regular 167100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * functions are changed to 64 bits) -- in case these are set on systems 167200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes * without large file support, _LFS64_LARGEFILE must also be true 167300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes */ 167409eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#ifdef Z_LARGE64 167500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); 167600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int)); 167700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile)); 167800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile)); 167900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t)); 168000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t)); 168100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 168200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 168309eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64) 168400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# ifdef Z_PREFIX_SET 168500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_gzopen z_gzopen64 168600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_gzseek z_gzseek64 168700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_gztell z_gztell64 168800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_gzoffset z_gzoffset64 168900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_adler32_combine z_adler32_combine64 169000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define z_crc32_combine z_crc32_combine64 169100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# else 169200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define gzopen gzopen64 169300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define gzseek gzseek64 169400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define gztell gztell64 169500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define gzoffset gzoffset64 169600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define adler32_combine adler32_combine64 169700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# define crc32_combine crc32_combine64 169800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# endif 169909eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes# ifndef Z_LARGE64 170000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); 170100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int)); 170200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile)); 170300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile)); 170400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t)); 170500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t)); 170600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes# endif 170700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#else 170800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); 170900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int)); 171000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gztell OF((gzFile)); 171100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile)); 171200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); 171300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); 171400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 171500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 171600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#else /* Z_SOLO */ 171700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 171800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); 171900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); 172000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 172100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif /* !Z_SOLO */ 172200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 172300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* hack for buggy compilers */ 172400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) 172500fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes struct internal_state {int dummy;}; 172600fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 172700fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 172800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes/* undocumented functions */ 172900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN const char * ZEXPORT zError OF((int)); 173000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp)); 173109eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott HughesZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table OF((void)); 173200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int)); 173300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp)); 173400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott HughesZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp)); 173509eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes#if defined(_WIN32) && !defined(Z_SOLO) 173609eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott HughesZEXTERN gzFile ZEXPORT gzopen_w OF((const wchar_t *path, 173709eb358bbbb9aad3fe48dd3368c8a7a481cbda1cElliott Hughes const char *mode)); 173800fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 173900fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 174000fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#ifdef __cplusplus 174100fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes} 174200fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif 174300fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes 174400fb66d0b1488e4ca655906f82b27eb2ccc3e309Elliott Hughes#endif /* ZLIB_H */ 1745