117651Speter/* zlib.h -- interface of the 'zlib' general purpose compression library 2250261Sdelphij version 1.2.8, April 28th, 2013 317651Speter 4250261Sdelphij Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler 517651Speter 617651Speter This software is provided 'as-is', without any express or implied 717651Speter warranty. In no event will the authors be held liable for any damages 817651Speter arising from the use of this software. 917651Speter 1017651Speter Permission is granted to anyone to use this software for any purpose, 1117651Speter including commercial applications, and to alter it and redistribute it 1217651Speter freely, subject to the following restrictions: 1317651Speter 1417651Speter 1. The origin of this software must not be misrepresented; you must not 1517651Speter claim that you wrote the original software. If you use this software 1617651Speter in a product, an acknowledgment in the product documentation would be 1717651Speter appreciated but is not required. 1817651Speter 2. Altered source versions must be plainly marked as such, and must not be 1917651Speter misrepresented as being the original software. 2017651Speter 3. This notice may not be removed or altered from any source distribution. 2117651Speter 2217651Speter Jean-loup Gailly Mark Adler 2333904Ssteve jloup@gzip.org madler@alumni.caltech.edu 2417651Speter 2517651Speter 2617651Speter The data format used by the zlib library is described by RFCs (Request for 27237410Sdelphij Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950 28237410Sdelphij (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format). 2917651Speter*/ 3017651Speter 31131377Stjr#ifndef ZLIB_H 32131377Stjr#define ZLIB_H 3317651Speter 3442468Speter#include "zconf.h" 3542468Speter 3617651Speter#ifdef __cplusplus 3717651Speterextern "C" { 3817651Speter#endif 3917651Speter 40250261Sdelphij#define ZLIB_VERSION "1.2.8" 41250261Sdelphij#define ZLIB_VERNUM 0x1280 42205471Sdelphij#define ZLIB_VER_MAJOR 1 43205471Sdelphij#define ZLIB_VER_MINOR 2 44250261Sdelphij#define ZLIB_VER_REVISION 8 45206924Sdelphij#define ZLIB_VER_SUBREVISION 0 4617651Speter 47131377Stjr/* 48205471Sdelphij The 'zlib' compression library provides in-memory compression and 49205471Sdelphij decompression functions, including integrity checks of the uncompressed data. 50205471Sdelphij This version of the library supports only one compression method (deflation) 51205471Sdelphij but other algorithms will be added later and will have the same stream 52205471Sdelphij interface. 5317651Speter 54205471Sdelphij Compression can be done in a single step if the buffers are large enough, 55205471Sdelphij or can be done by repeated calls of the compression function. In the latter 56205471Sdelphij case, the application must provide more input and/or consume the output 5717651Speter (providing more output space) before each call. 5817651Speter 59205471Sdelphij The compressed data format used by default by the in-memory functions is 60145474Skientzle the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped 61145474Skientzle around a deflate stream, which is itself documented in RFC 1951. 62131377Stjr 63205471Sdelphij The library also supports reading and writing files in gzip (.gz) format 64131377Stjr with an interface similar to that of stdio using the functions that start 65131377Stjr with "gz". The gzip format is different from the zlib format. gzip is a 66131377Stjr gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. 6733904Ssteve 68205471Sdelphij This library can optionally read and write gzip streams in memory as well. 69145474Skientzle 70205471Sdelphij The zlib format was designed to be compact and fast for use in memory 71131377Stjr and on communications channels. The gzip format was designed for single- 72131377Stjr file compression on file systems, has a larger header than zlib to maintain 73131377Stjr directory information, and uses a different, slower check method than zlib. 74131377Stjr 75205471Sdelphij The library does not install any signal handler. The decoder checks 76205471Sdelphij the consistency of the compressed data, so the library should never crash 77205471Sdelphij even in case of corrupted input. 7817651Speter*/ 7917651Speter 8017651Spetertypedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); 8117651Spetertypedef void (*free_func) OF((voidpf opaque, voidpf address)); 8217651Speter 8317651Speterstruct internal_state; 8417651Speter 8517651Spetertypedef struct z_stream_s { 86237410Sdelphij z_const Bytef *next_in; /* next input byte */ 8717651Speter uInt avail_in; /* number of bytes available at next_in */ 88237410Sdelphij uLong total_in; /* total number of input bytes read so far */ 8917651Speter 9017651Speter Bytef *next_out; /* next output byte should be put there */ 9117651Speter uInt avail_out; /* remaining free space at next_out */ 92237410Sdelphij uLong total_out; /* total number of bytes output so far */ 9317651Speter 94237410Sdelphij z_const char *msg; /* last error message, NULL if no error */ 9517651Speter struct internal_state FAR *state; /* not visible by applications */ 9617651Speter 9717651Speter alloc_func zalloc; /* used to allocate the internal state */ 9817651Speter free_func zfree; /* used to free the internal state */ 9917651Speter voidpf opaque; /* private data object passed to zalloc and zfree */ 10017651Speter 101157043Sdes int data_type; /* best guess about the data type: binary or text */ 10217651Speter uLong adler; /* adler32 value of the uncompressed data */ 10317651Speter uLong reserved; /* reserved for future use */ 10417651Speter} z_stream; 10517651Speter 10617651Spetertypedef z_stream FAR *z_streamp; 10717651Speter 10817651Speter/* 109157043Sdes gzip header information passed to and from zlib routines. See RFC 1952 110157043Sdes for more details on the meanings of these fields. 111157043Sdes*/ 112157043Sdestypedef struct gz_header_s { 113157043Sdes int text; /* true if compressed data believed to be text */ 114157043Sdes uLong time; /* modification time */ 115157043Sdes int xflags; /* extra flags (not used when writing a gzip file) */ 116157043Sdes int os; /* operating system */ 117157043Sdes Bytef *extra; /* pointer to extra field or Z_NULL if none */ 118157043Sdes uInt extra_len; /* extra field length (valid if extra != Z_NULL) */ 119157043Sdes uInt extra_max; /* space at extra (only when reading header) */ 120157043Sdes Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ 121157043Sdes uInt name_max; /* space at name (only when reading header) */ 122157043Sdes Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */ 123157043Sdes uInt comm_max; /* space at comment (only when reading header) */ 124157043Sdes int hcrc; /* true if there was or will be a header crc */ 125157043Sdes int done; /* true when done reading gzip header (not used 126157043Sdes when writing a gzip file) */ 127157043Sdes} gz_header; 128157043Sdes 129157043Sdestypedef gz_header FAR *gz_headerp; 130157043Sdes 131157043Sdes/* 132205471Sdelphij The application must update next_in and avail_in when avail_in has dropped 133205471Sdelphij to zero. It must update next_out and avail_out when avail_out has dropped 134205471Sdelphij to zero. The application must initialize zalloc, zfree and opaque before 135205471Sdelphij calling the init function. All other fields are set by the compression 136205471Sdelphij library and must not be updated by the application. 13717651Speter 138205471Sdelphij The opaque value provided by the application will be passed as the first 139205471Sdelphij parameter for calls of zalloc and zfree. This can be useful for custom 140205471Sdelphij memory management. The compression library attaches no meaning to the 14117651Speter opaque value. 14217651Speter 143205471Sdelphij zalloc must return Z_NULL if there is not enough memory for the object. 14433904Ssteve If zlib is used in a multi-threaded application, zalloc and zfree must be 14533904Ssteve thread safe. 14633904Ssteve 147205471Sdelphij On 16-bit systems, the functions zalloc and zfree must be able to allocate 148205471Sdelphij exactly 65536 bytes, but will not be required to allocate more than this if 149205471Sdelphij the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers 150205471Sdelphij returned by zalloc for objects of exactly 65536 bytes *must* have their 151205471Sdelphij offset normalized to zero. The default allocation function provided by this 152205471Sdelphij library ensures this (see zutil.c). To reduce memory requirements and avoid 153205471Sdelphij any allocation of 64K objects, at the expense of compression ratio, compile 154205471Sdelphij the library with -DMAX_WBITS=14 (see zconf.h). 15517651Speter 156205471Sdelphij The fields total_in and total_out can be used for statistics or progress 157205471Sdelphij reports. After compression, total_in holds the total size of the 158205471Sdelphij uncompressed data and may be saved for use in the decompressor (particularly 159205471Sdelphij if the decompressor wants to decompress everything in a single step). 16017651Speter*/ 16117651Speter 16217651Speter /* constants */ 16317651Speter 16417651Speter#define Z_NO_FLUSH 0 165205471Sdelphij#define Z_PARTIAL_FLUSH 1 16617651Speter#define Z_SYNC_FLUSH 2 16717651Speter#define Z_FULL_FLUSH 3 16817651Speter#define Z_FINISH 4 169131377Stjr#define Z_BLOCK 5 170205471Sdelphij#define Z_TREES 6 171131377Stjr/* Allowed flush values; see deflate() and inflate() below for details */ 17217651Speter 17317651Speter#define Z_OK 0 17417651Speter#define Z_STREAM_END 1 17517651Speter#define Z_NEED_DICT 2 17617651Speter#define Z_ERRNO (-1) 17717651Speter#define Z_STREAM_ERROR (-2) 17817651Speter#define Z_DATA_ERROR (-3) 17917651Speter#define Z_MEM_ERROR (-4) 18017651Speter#define Z_BUF_ERROR (-5) 18117651Speter#define Z_VERSION_ERROR (-6) 182205471Sdelphij/* Return codes for the compression/decompression functions. Negative values 183205471Sdelphij * are errors, positive values are used for special but normal events. 18417651Speter */ 18517651Speter 18617651Speter#define Z_NO_COMPRESSION 0 18717651Speter#define Z_BEST_SPEED 1 18817651Speter#define Z_BEST_COMPRESSION 9 18917651Speter#define Z_DEFAULT_COMPRESSION (-1) 19017651Speter/* compression levels */ 19117651Speter 19217651Speter#define Z_FILTERED 1 19317651Speter#define Z_HUFFMAN_ONLY 2 194131377Stjr#define Z_RLE 3 195157043Sdes#define Z_FIXED 4 19617651Speter#define Z_DEFAULT_STRATEGY 0 19717651Speter/* compression strategy; see deflateInit2() below for details */ 19817651Speter 19917651Speter#define Z_BINARY 0 200157043Sdes#define Z_TEXT 1 201157043Sdes#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ 20217651Speter#define Z_UNKNOWN 2 203131377Stjr/* Possible values of the data_type field (though see inflate()) */ 20417651Speter 20517651Speter#define Z_DEFLATED 8 20617651Speter/* The deflate compression method (the only one supported in this version) */ 20717651Speter 20817651Speter#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ 20917651Speter 21017651Speter#define zlib_version zlibVersion() 21117651Speter/* for compatibility with versions < 1.0.2 */ 21217651Speter 213205471Sdelphij 21417651Speter /* basic functions */ 21517651Speter 21642468SpeterZEXTERN const char * ZEXPORT zlibVersion OF((void)); 21717651Speter/* The application can compare zlibVersion and ZLIB_VERSION for consistency. 218205471Sdelphij If the first character differs, the library code actually used is not 219205471Sdelphij compatible with the zlib.h header file used by the application. This check 220205471Sdelphij is automatically made by deflateInit and inflateInit. 22117651Speter */ 22217651Speter 223131377Stjr/* 22442468SpeterZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); 22517651Speter 226205471Sdelphij Initializes the internal stream state for compression. The fields 227205471Sdelphij zalloc, zfree and opaque must be initialized before by the caller. If 228205471Sdelphij zalloc and zfree are set to Z_NULL, deflateInit updates them to use default 229205471Sdelphij allocation functions. 23017651Speter 23117651Speter The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: 232205471Sdelphij 1 gives best speed, 9 gives best compression, 0 gives no compression at all 233205471Sdelphij (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION 234205471Sdelphij requests a default compromise between speed and compression (currently 235205471Sdelphij equivalent to level 6). 23617651Speter 237205471Sdelphij deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 238205471Sdelphij memory, Z_STREAM_ERROR if level is not a valid compression level, or 23917651Speter Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible 240205471Sdelphij with the version assumed by the caller (ZLIB_VERSION). msg is set to null 241205471Sdelphij if there is no error message. deflateInit does not perform any compression: 242205471Sdelphij this will be done by deflate(). 24317651Speter*/ 24417651Speter 24517651Speter 24642468SpeterZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); 24717651Speter/* 24833904Ssteve deflate compresses as much data as possible, and stops when the input 249205471Sdelphij buffer becomes empty or the output buffer becomes full. It may introduce 250205471Sdelphij some output latency (reading input without producing any output) except when 25133904Ssteve forced to flush. 25217651Speter 253205471Sdelphij The detailed semantics are as follows. deflate performs one or both of the 25433904Ssteve following actions: 25533904Ssteve 25617651Speter - Compress more input starting at next_in and update next_in and avail_in 257205471Sdelphij accordingly. If not all input can be processed (because there is not 25817651Speter enough room in the output buffer), next_in and avail_in are updated and 25917651Speter processing will resume at this point for the next call of deflate(). 26017651Speter 26117651Speter - Provide more output starting at next_out and update next_out and avail_out 262205471Sdelphij accordingly. This action is forced if the parameter flush is non zero. 26317651Speter Forcing flush frequently degrades the compression ratio, so this parameter 264205471Sdelphij should be set only when necessary (in interactive applications). Some 265205471Sdelphij output may be provided even if flush is not set. 26617651Speter 267205471Sdelphij Before the call of deflate(), the application should ensure that at least 268205471Sdelphij one of the actions is possible, by providing more input and/or consuming more 269205471Sdelphij output, and updating avail_in or avail_out accordingly; avail_out should 270205471Sdelphij never be zero before the call. The application can consume the compressed 271205471Sdelphij output when it wants, for example when the output buffer is full (avail_out 272205471Sdelphij == 0), or after each call of deflate(). If deflate returns Z_OK and with 273205471Sdelphij zero avail_out, it must be called again after making room in the output 274205471Sdelphij buffer because there might be more output pending. 27517651Speter 276157043Sdes Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to 277205471Sdelphij decide how much data to accumulate before producing output, in order to 278157043Sdes maximize compression. 279157043Sdes 28033904Ssteve If the parameter flush is set to Z_SYNC_FLUSH, all pending output is 28133904Ssteve flushed to the output buffer and the output is aligned on a byte boundary, so 282205471Sdelphij that the decompressor can get all input data available so far. (In 283205471Sdelphij particular avail_in is zero after the call if enough output space has been 284205471Sdelphij provided before the call.) Flushing may degrade compression for some 285205471Sdelphij compression algorithms and so it should be used only when necessary. This 286205471Sdelphij completes the current deflate block and follows it with an empty stored block 287205471Sdelphij that is three bits plus filler bits to the next byte, followed by four bytes 288205471Sdelphij (00 00 ff ff). 28917651Speter 290205471Sdelphij If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the 291205471Sdelphij output buffer, but the output is not aligned to a byte boundary. All of the 292205471Sdelphij input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. 293205471Sdelphij This completes the current deflate block and follows it with an empty fixed 294205471Sdelphij codes block that is 10 bits long. This assures that enough bytes are output 295205471Sdelphij in order for the decompressor to finish the block before the empty fixed code 296205471Sdelphij block. 297205471Sdelphij 298205471Sdelphij If flush is set to Z_BLOCK, a deflate block is completed and emitted, as 299205471Sdelphij for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to 300205471Sdelphij seven bits of the current block are held to be written as the next byte after 301205471Sdelphij the next deflate block is completed. In this case, the decompressor may not 302205471Sdelphij be provided enough bits at this point in order to complete decompression of 303205471Sdelphij the data provided so far to the compressor. It may need to wait for the next 304205471Sdelphij block to be emitted. This is for advanced applications that need to control 305205471Sdelphij the emission of deflate blocks. 306205471Sdelphij 30733904Ssteve If flush is set to Z_FULL_FLUSH, all output is flushed as with 30833904Ssteve Z_SYNC_FLUSH, and the compression state is reset so that decompression can 30933904Ssteve restart from this point if previous compressed data has been damaged or if 310205471Sdelphij random access is desired. Using Z_FULL_FLUSH too often can seriously degrade 311157043Sdes compression. 31233904Ssteve 31333904Ssteve If deflate returns with avail_out == 0, this function must be called again 31433904Ssteve with the same value of the flush parameter and more output space (updated 31533904Ssteve avail_out), until the flush is complete (deflate returns with non-zero 316205471Sdelphij avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that 317131377Stjr avail_out is greater than six to avoid repeated flush markers due to 318131377Stjr avail_out == 0 on return. 31933904Ssteve 32017651Speter If the parameter flush is set to Z_FINISH, pending input is processed, 321205471Sdelphij pending output is flushed and deflate returns with Z_STREAM_END if there was 322205471Sdelphij enough output space; if deflate returns with Z_OK, this function must be 32317651Speter called again with Z_FINISH and more output space (updated avail_out) but no 324205471Sdelphij more input data, until it returns with Z_STREAM_END or an error. After 325205471Sdelphij deflate has returned Z_STREAM_END, the only possible operations on the stream 326205471Sdelphij are deflateReset or deflateEnd. 327131377Stjr 32817651Speter Z_FINISH can be used immediately after deflateInit if all the compression 329205471Sdelphij is to be done in a single step. In this case, avail_out must be at least the 330237410Sdelphij value returned by deflateBound (see below). Then deflate is guaranteed to 331237410Sdelphij return Z_STREAM_END. If not enough output space is provided, deflate will 332237410Sdelphij not return Z_STREAM_END, and it must be called again as described above. 33317651Speter 33433904Ssteve deflate() sets strm->adler to the adler32 checksum of all input read 33533904Ssteve so far (that is, total_in bytes). 33633904Ssteve 337157043Sdes deflate() may update strm->data_type if it can make a good guess about 338205471Sdelphij the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered 339205471Sdelphij binary. This field is only for information purposes and does not affect the 340205471Sdelphij compression algorithm in any manner. 34117651Speter 34217651Speter deflate() returns Z_OK if some progress has been made (more input 34317651Speter processed or more output produced), Z_STREAM_END if all input has been 34417651Speter consumed and all output has been produced (only when flush is set to 34517651Speter Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example 346205471Sdelphij if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible 347205471Sdelphij (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not 348131377Stjr fatal, and deflate() can be called again with more input and more output 349131377Stjr space to continue compressing. 35017651Speter*/ 35117651Speter 35217651Speter 35342468SpeterZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); 35417651Speter/* 35517651Speter All dynamically allocated data structures for this stream are freed. 356205471Sdelphij This function discards any unprocessed input and does not flush any pending 357205471Sdelphij output. 35817651Speter 35917651Speter deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the 36017651Speter stream state was inconsistent, Z_DATA_ERROR if the stream was freed 361205471Sdelphij prematurely (some input or output was discarded). In the error case, msg 362205471Sdelphij may be set but then points to a static string (which must not be 36317651Speter deallocated). 36417651Speter*/ 36517651Speter 36617651Speter 367131377Stjr/* 36842468SpeterZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); 36917651Speter 370205471Sdelphij Initializes the internal stream state for decompression. The fields 37133904Ssteve next_in, avail_in, zalloc, zfree and opaque must be initialized before by 372205471Sdelphij the caller. If next_in is not Z_NULL and avail_in is large enough (the 373205471Sdelphij exact value depends on the compression method), inflateInit determines the 37433904Ssteve compression method from the zlib header and allocates all data structures 37533904Ssteve accordingly; otherwise the allocation will be deferred to the first call of 37633904Ssteve inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to 37733904Ssteve use default allocation functions. 37817651Speter 37933904Ssteve inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 38033904Ssteve memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 381205471Sdelphij version assumed by the caller, or Z_STREAM_ERROR if the parameters are 382205471Sdelphij invalid, such as a null pointer to the structure. msg is set to null if 383205471Sdelphij there is no error message. inflateInit does not perform any decompression 384205471Sdelphij apart from possibly reading the zlib header if present: actual decompression 385205471Sdelphij will be done by inflate(). (So next_in and avail_in may be modified, but 386205471Sdelphij next_out and avail_out are unused and unchanged.) The current implementation 387205471Sdelphij of inflateInit() does not process any header information -- that is deferred 388205471Sdelphij until inflate() is called. 38917651Speter*/ 39017651Speter 39117651Speter 39242468SpeterZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); 39317651Speter/* 39433904Ssteve inflate decompresses as much data as possible, and stops when the input 395205471Sdelphij buffer becomes empty or the output buffer becomes full. It may introduce 396131377Stjr some output latency (reading input without producing any output) except when 397131377Stjr forced to flush. 39817651Speter 399205471Sdelphij The detailed semantics are as follows. inflate performs one or both of the 40033904Ssteve following actions: 40133904Ssteve 40217651Speter - Decompress more input starting at next_in and update next_in and avail_in 403205471Sdelphij accordingly. If not all input can be processed (because there is not 404205471Sdelphij enough room in the output buffer), next_in is updated and processing will 405205471Sdelphij resume at this point for the next call of inflate(). 40617651Speter 40717651Speter - Provide more output starting at next_out and update next_out and avail_out 408205471Sdelphij accordingly. inflate() provides as much output as possible, until there is 409205471Sdelphij no more input data or no more space in the output buffer (see below about 410205471Sdelphij the flush parameter). 41117651Speter 412205471Sdelphij Before the call of inflate(), the application should ensure that at least 413205471Sdelphij one of the actions is possible, by providing more input and/or consuming more 414205471Sdelphij output, and updating the next_* and avail_* values accordingly. The 415205471Sdelphij application can consume the uncompressed output when it wants, for example 416205471Sdelphij when the output buffer is full (avail_out == 0), or after each call of 417205471Sdelphij inflate(). If inflate returns Z_OK and with zero avail_out, it must be 418205471Sdelphij called again after making room in the output buffer because there might be 419205471Sdelphij more output pending. 42017651Speter 421205471Sdelphij The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH, 422205471Sdelphij Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much 423205471Sdelphij output as possible to the output buffer. Z_BLOCK requests that inflate() 424205471Sdelphij stop if and when it gets to the next deflate block boundary. When decoding 425205471Sdelphij the zlib or gzip format, this will cause inflate() to return immediately 426205471Sdelphij after the header and before the first block. When doing a raw inflate, 427205471Sdelphij inflate() will go ahead and process the first block, and will return when it 428205471Sdelphij gets to the end of that block, or when it runs out of data. 42917651Speter 430131377Stjr The Z_BLOCK option assists in appending to or combining deflate streams. 431131377Stjr Also to assist in this, on return inflate() will set strm->data_type to the 432205471Sdelphij number of unused bits in the last byte taken from strm->next_in, plus 64 if 433205471Sdelphij inflate() is currently decoding the last block in the deflate stream, plus 434205471Sdelphij 128 if inflate() returned immediately after decoding an end-of-block code or 435205471Sdelphij decoding the complete header up to just before the first byte of the deflate 436205471Sdelphij stream. The end-of-block will not be indicated until all of the uncompressed 437205471Sdelphij data from that block has been written to strm->next_out. The number of 438205471Sdelphij unused bits may in general be greater than seven, except when bit 7 of 439205471Sdelphij data_type is set, in which case the number of unused bits will be less than 440205471Sdelphij eight. data_type is set as noted here every time inflate() returns for all 441205471Sdelphij flush options, and so can be used to determine the amount of currently 442205471Sdelphij consumed input in bits. 443131377Stjr 444205471Sdelphij The Z_TREES option behaves as Z_BLOCK does, but it also returns when the 445205471Sdelphij end of each deflate block header is reached, before any actual data in that 446205471Sdelphij block is decoded. This allows the caller to determine the length of the 447205471Sdelphij deflate block header for later use in random access within a deflate block. 448205471Sdelphij 256 is added to the value of strm->data_type when inflate() returns 449205471Sdelphij immediately after reaching the end of the deflate block header. 450205471Sdelphij 45117651Speter inflate() should normally be called until it returns Z_STREAM_END or an 452205471Sdelphij error. However if all decompression is to be performed in a single step (a 453205471Sdelphij single call of inflate), the parameter flush should be set to Z_FINISH. In 454205471Sdelphij this case all pending input is processed and all pending output is flushed; 455237410Sdelphij avail_out must be large enough to hold all of the uncompressed data for the 456237410Sdelphij operation to complete. (The size of the uncompressed data may have been 457237410Sdelphij saved by the compressor for this purpose.) The use of Z_FINISH is not 458237410Sdelphij required to perform an inflation in one step. However it may be used to 459237410Sdelphij inform inflate that a faster approach can be used for the single inflate() 460237410Sdelphij call. Z_FINISH also informs inflate to not maintain a sliding window if the 461237410Sdelphij stream completes, which reduces inflate's memory footprint. If the stream 462237410Sdelphij does not complete, either because not all of the stream is provided or not 463237410Sdelphij enough output space is provided, then a sliding window will be allocated and 464237410Sdelphij inflate() can be called again to continue the operation as if Z_NO_FLUSH had 465237410Sdelphij been used. 46617651Speter 467131377Stjr In this implementation, inflate() always flushes as much output as 468131377Stjr possible to the output buffer, and always uses the faster approach on the 469237410Sdelphij first call. So the effects of the flush parameter in this implementation are 470237410Sdelphij on the return value of inflate() as noted below, when inflate() returns early 471237410Sdelphij when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of 472237410Sdelphij memory for a sliding window when Z_FINISH is used. 47333904Ssteve 474131377Stjr If a preset dictionary is needed after this call (see inflateSetDictionary 475237410Sdelphij below), inflate sets strm->adler to the Adler-32 checksum of the dictionary 476131377Stjr chosen by the compressor and returns Z_NEED_DICT; otherwise it sets 477237410Sdelphij strm->adler to the Adler-32 checksum of all output produced so far (that is, 478131377Stjr total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described 479205471Sdelphij below. At the end of the stream, inflate() checks that its computed adler32 480131377Stjr checksum is equal to that saved by the compressor and returns Z_STREAM_END 481131377Stjr only if the checksum is correct. 482131377Stjr 483205471Sdelphij inflate() can decompress and check either zlib-wrapped or gzip-wrapped 484205471Sdelphij deflate data. The header type is detected automatically, if requested when 485205471Sdelphij initializing with inflateInit2(). Any information contained in the gzip 486205471Sdelphij header is not retained, so applications that need that information should 487205471Sdelphij instead use raw inflate, see inflateInit2() below, or inflateBack() and 488237410Sdelphij perform their own processing of the gzip header and trailer. When processing 489237410Sdelphij gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output 490237410Sdelphij producted so far. The CRC-32 is checked against the gzip trailer. 491131377Stjr 49233904Ssteve inflate() returns Z_OK if some progress has been made (more input processed 49333904Ssteve or more output produced), Z_STREAM_END if the end of the compressed data has 49433904Ssteve been reached and all uncompressed output has been produced, Z_NEED_DICT if a 49533904Ssteve preset dictionary is needed at this point, Z_DATA_ERROR if the input data was 496131377Stjr corrupted (input stream not conforming to the zlib format or incorrect check 497131377Stjr value), Z_STREAM_ERROR if the stream structure was inconsistent (for example 498205471Sdelphij next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory, 499131377Stjr Z_BUF_ERROR if no progress is possible or if there was not enough room in the 500205471Sdelphij output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and 501131377Stjr inflate() can be called again with more input and more output space to 502205471Sdelphij continue decompressing. If Z_DATA_ERROR is returned, the application may 503205471Sdelphij then call inflateSync() to look for a good compression block if a partial 504205471Sdelphij recovery of the data is desired. 50517651Speter*/ 50617651Speter 50717651Speter 50842468SpeterZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); 50917651Speter/* 51017651Speter All dynamically allocated data structures for this stream are freed. 511205471Sdelphij This function discards any unprocessed input and does not flush any pending 512205471Sdelphij output. 51317651Speter 51417651Speter inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state 515205471Sdelphij was inconsistent. In the error case, msg may be set but then points to a 51617651Speter static string (which must not be deallocated). 51717651Speter*/ 51817651Speter 519205471Sdelphij 52017651Speter /* Advanced functions */ 52117651Speter 52217651Speter/* 52317651Speter The following functions are needed only in some special applications. 52417651Speter*/ 52517651Speter 526131377Stjr/* 52742468SpeterZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, 52842468Speter int level, 52942468Speter int method, 53042468Speter int windowBits, 53142468Speter int memLevel, 53242468Speter int strategy)); 53317651Speter 534205471Sdelphij This is another version of deflateInit with more compression options. The 535205471Sdelphij fields next_in, zalloc, zfree and opaque must be initialized before by the 536205471Sdelphij caller. 53717651Speter 538205471Sdelphij The method parameter is the compression method. It must be Z_DEFLATED in 53933904Ssteve this version of the library. 54017651Speter 54117651Speter The windowBits parameter is the base two logarithm of the window size 542205471Sdelphij (the size of the history buffer). It should be in the range 8..15 for this 543205471Sdelphij version of the library. Larger values of this parameter result in better 544205471Sdelphij compression at the expense of memory usage. The default value is 15 if 54533904Ssteve deflateInit is used instead. 54617651Speter 547205471Sdelphij windowBits can also be -8..-15 for raw deflate. In this case, -windowBits 548205471Sdelphij determines the window size. deflate() will then generate raw deflate data 549131377Stjr with no zlib header or trailer, and will not compute an adler32 check value. 550131377Stjr 551205471Sdelphij windowBits can also be greater than 15 for optional gzip encoding. Add 552131377Stjr 16 to windowBits to write a simple gzip header and trailer around the 553205471Sdelphij compressed data instead of a zlib wrapper. The gzip header will have no 554205471Sdelphij file name, no extra data, no comment, no modification time (set to zero), no 555205471Sdelphij header crc, and the operating system will be set to 255 (unknown). If a 556145474Skientzle gzip stream is being written, strm->adler is a crc32 instead of an adler32. 557131377Stjr 55817651Speter The memLevel parameter specifies how much memory should be allocated 559205471Sdelphij for the internal compression state. memLevel=1 uses minimum memory but is 560205471Sdelphij slow and reduces compression ratio; memLevel=9 uses maximum memory for 561205471Sdelphij optimal speed. The default value is 8. See zconf.h for total memory usage 562205471Sdelphij as a function of windowBits and memLevel. 56317651Speter 564205471Sdelphij The strategy parameter is used to tune the compression algorithm. Use the 56517651Speter value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a 566131377Stjr filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no 567131377Stjr string match), or Z_RLE to limit match distances to one (run-length 568205471Sdelphij encoding). Filtered data consists mostly of small values with a somewhat 569205471Sdelphij random distribution. In this case, the compression algorithm is tuned to 570205471Sdelphij compress them better. The effect of Z_FILTERED is to force more Huffman 571131377Stjr coding and less string matching; it is somewhat intermediate between 572205471Sdelphij Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as 573205471Sdelphij fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The 574205471Sdelphij strategy parameter only affects the compression ratio but not the 575205471Sdelphij correctness of the compressed output even if it is not set appropriately. 576205471Sdelphij Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler 577205471Sdelphij decoder for special applications. 57817651Speter 579205471Sdelphij deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 580205471Sdelphij memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid 581205471Sdelphij method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is 582205471Sdelphij incompatible with the version assumed by the caller (ZLIB_VERSION). msg is 583205471Sdelphij set to null if there is no error message. deflateInit2 does not perform any 584205471Sdelphij compression: this will be done by deflate(). 58517651Speter*/ 586131377Stjr 58742468SpeterZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, 58842468Speter const Bytef *dictionary, 58942468Speter uInt dictLength)); 59017651Speter/* 59133904Ssteve Initializes the compression dictionary from the given byte sequence 592237410Sdelphij without producing any compressed output. When using the zlib format, this 593237410Sdelphij function must be called immediately after deflateInit, deflateInit2 or 594237410Sdelphij deflateReset, and before any call of deflate. When doing raw deflate, this 595237410Sdelphij function must be called either before any call of deflate, or immediately 596237410Sdelphij after the completion of a deflate block, i.e. after all input has been 597237410Sdelphij consumed and all output has been delivered when using any of the flush 598237410Sdelphij options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The 599237410Sdelphij compressor and decompressor must use exactly the same dictionary (see 600237410Sdelphij inflateSetDictionary). 60133904Ssteve 60217651Speter The dictionary should consist of strings (byte sequences) that are likely 60317651Speter to be encountered later in the data to be compressed, with the most commonly 604205471Sdelphij used strings preferably put towards the end of the dictionary. Using a 60533904Ssteve dictionary is most useful when the data to be compressed is short and can be 60633904Ssteve predicted with good accuracy; the data can then be compressed better than 60733904Ssteve with the default empty dictionary. 60833904Ssteve 60933904Ssteve Depending on the size of the compression data structures selected by 61033904Ssteve deflateInit or deflateInit2, a part of the dictionary may in effect be 611205471Sdelphij discarded, for example if the dictionary is larger than the window size 612205471Sdelphij provided in deflateInit or deflateInit2. Thus the strings most likely to be 613205471Sdelphij useful should be put at the end of the dictionary, not at the front. In 614205471Sdelphij addition, the current implementation of deflate will use at most the window 615205471Sdelphij size minus 262 bytes of the provided dictionary. 61633904Ssteve 617131377Stjr Upon return of this function, strm->adler is set to the adler32 value 61817651Speter of the dictionary; the decompressor may later use this value to determine 619205471Sdelphij which dictionary has been used by the compressor. (The adler32 value 62017651Speter applies to the whole dictionary even if only a subset of the dictionary is 621131377Stjr actually used by the compressor.) If a raw deflate was requested, then the 622131377Stjr adler32 value is not computed and strm->adler is not set. 62317651Speter 62417651Speter deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a 625205471Sdelphij parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is 62633904Ssteve inconsistent (for example if deflate has already been called for this stream 627237410Sdelphij or if not at a block boundary for raw deflate). deflateSetDictionary does 628237410Sdelphij not perform any compression: this will be done by deflate(). 62917651Speter*/ 63017651Speter 63142468SpeterZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, 63242468Speter z_streamp source)); 63317651Speter/* 63433904Ssteve Sets the destination stream as a complete copy of the source stream. 63517651Speter 63617651Speter This function can be useful when several compression strategies will be 63717651Speter tried, for example when there are several ways of pre-processing the input 638205471Sdelphij data with a filter. The streams that will be discarded should then be freed 63917651Speter by calling deflateEnd. Note that deflateCopy duplicates the internal 640205471Sdelphij compression state which can be quite large, so this strategy is slow and can 641205471Sdelphij consume lots of memory. 64217651Speter 64317651Speter deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 64417651Speter enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 645205471Sdelphij (such as zalloc being Z_NULL). msg is left unchanged in both source and 64617651Speter destination. 64717651Speter*/ 64817651Speter 64942468SpeterZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); 65017651Speter/* 65117651Speter This function is equivalent to deflateEnd followed by deflateInit, 652205471Sdelphij but does not free and reallocate all the internal compression state. The 653205471Sdelphij stream will keep the same compression level and any other attributes that 654205471Sdelphij may have been set by deflateInit2. 65517651Speter 656205471Sdelphij deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 657205471Sdelphij stream state was inconsistent (such as zalloc or state being Z_NULL). 65817651Speter*/ 65917651Speter 66042468SpeterZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, 661131377Stjr int level, 662131377Stjr int strategy)); 66317651Speter/* 66433904Ssteve Dynamically update the compression level and compression strategy. The 66533904Ssteve interpretation of level and strategy is as in deflateInit2. This can be 66633904Ssteve used to switch between compression and straight copy of the input data, or 667205471Sdelphij to switch to a different kind of input data requiring a different strategy. 668205471Sdelphij If the compression level is changed, the input available so far is 669205471Sdelphij compressed with the old level (and may be flushed); the new level will take 670205471Sdelphij effect only at the next call of deflate(). 67117651Speter 67217651Speter Before the call of deflateParams, the stream state must be set as for 673205471Sdelphij a call of deflate(), since the currently available input may have to be 674205471Sdelphij compressed and flushed. In particular, strm->avail_out must be non-zero. 67517651Speter 67617651Speter deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source 677205471Sdelphij stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if 678205471Sdelphij strm->avail_out was zero. 67917651Speter*/ 68017651Speter 681157043SdesZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, 682157043Sdes int good_length, 683157043Sdes int max_lazy, 684157043Sdes int nice_length, 685157043Sdes int max_chain)); 686157043Sdes/* 687157043Sdes Fine tune deflate's internal compression parameters. This should only be 688157043Sdes used by someone who understands the algorithm used by zlib's deflate for 689157043Sdes searching for the best matching string, and even then only by the most 690157043Sdes fanatic optimizer trying to squeeze out the last compressed bit for their 691157043Sdes specific input data. Read the deflate.c source code for the meaning of the 692157043Sdes max_lazy, good_length, nice_length, and max_chain parameters. 693157043Sdes 694157043Sdes deflateTune() can be called after deflateInit() or deflateInit2(), and 695157043Sdes returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. 696157043Sdes */ 697157043Sdes 698131377StjrZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, 699131377Stjr uLong sourceLen)); 700131377Stjr/* 701131377Stjr deflateBound() returns an upper bound on the compressed size after 702205471Sdelphij deflation of sourceLen bytes. It must be called after deflateInit() or 703205471Sdelphij deflateInit2(), and after deflateSetHeader(), if used. This would be used 704205471Sdelphij to allocate an output buffer for deflation in a single pass, and so would be 705237410Sdelphij called before deflate(). If that first deflate() call is provided the 706237410Sdelphij sourceLen input bytes, an output buffer allocated to the size returned by 707237410Sdelphij deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed 708237410Sdelphij to return Z_STREAM_END. Note that it is possible for the compressed size to 709237410Sdelphij be larger than the value returned by deflateBound() if flush options other 710237410Sdelphij than Z_FINISH or Z_NO_FLUSH are used. 711131377Stjr*/ 712131377Stjr 713237410SdelphijZEXTERN int ZEXPORT deflatePending OF((z_streamp strm, 714237410Sdelphij unsigned *pending, 715237410Sdelphij int *bits)); 716237410Sdelphij/* 717237410Sdelphij deflatePending() returns the number of bytes and bits of output that have 718237410Sdelphij been generated, but not yet provided in the available output. The bytes not 719237410Sdelphij provided would be due to the available output space having being consumed. 720237410Sdelphij The number of bits of output not provided are between 0 and 7, where they 721237410Sdelphij await more bits to join them in order to fill out a full byte. If pending 722237410Sdelphij or bits are Z_NULL, then those values are not set. 723237410Sdelphij 724237410Sdelphij deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source 725237410Sdelphij stream state was inconsistent. 726237410Sdelphij */ 727237410Sdelphij 728131377StjrZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, 729131377Stjr int bits, 730131377Stjr int value)); 731131377Stjr/* 732131377Stjr deflatePrime() inserts bits in the deflate output stream. The intent 733205471Sdelphij is that this function is used to start off the deflate output with the bits 734205471Sdelphij leftover from a previous deflate stream when appending to it. As such, this 735205471Sdelphij function can only be used for raw deflate, and must be used before the first 736205471Sdelphij deflate() call after a deflateInit2() or deflateReset(). bits must be less 737205471Sdelphij than or equal to 16, and that many of the least significant bits of value 738205471Sdelphij will be inserted in the output. 739131377Stjr 740237410Sdelphij deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough 741237410Sdelphij room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the 742237410Sdelphij source stream state was inconsistent. 743131377Stjr*/ 744131377Stjr 745157043SdesZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, 746157043Sdes gz_headerp head)); 747131377Stjr/* 748205471Sdelphij deflateSetHeader() provides gzip header information for when a gzip 749157043Sdes stream is requested by deflateInit2(). deflateSetHeader() may be called 750157043Sdes after deflateInit2() or deflateReset() and before the first call of 751157043Sdes deflate(). The text, time, os, extra field, name, and comment information 752157043Sdes in the provided gz_header structure are written to the gzip header (xflag is 753157043Sdes ignored -- the extra flags are set according to the compression level). The 754157043Sdes caller must assure that, if not Z_NULL, name and comment are terminated with 755157043Sdes a zero byte, and that if extra is not Z_NULL, that extra_len bytes are 756157043Sdes available there. If hcrc is true, a gzip header crc is included. Note that 757157043Sdes the current versions of the command-line version of gzip (up through version 758157043Sdes 1.3.x) do not support header crc's, and will report that it is a "multi-part 759157043Sdes gzip file" and give up. 760157043Sdes 761205471Sdelphij If deflateSetHeader is not used, the default gzip header has text false, 762157043Sdes the time set to zero, and os set to 255, with no extra, name, or comment 763157043Sdes fields. The gzip header is returned to the default state by deflateReset(). 764157043Sdes 765205471Sdelphij deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 766157043Sdes stream state was inconsistent. 767157043Sdes*/ 768157043Sdes 769157043Sdes/* 77042468SpeterZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, 77142468Speter int windowBits)); 77217651Speter 773205471Sdelphij This is another version of inflateInit with an extra parameter. The 77433904Ssteve fields next_in, avail_in, zalloc, zfree and opaque must be initialized 77533904Ssteve before by the caller. 77617651Speter 77717651Speter The windowBits parameter is the base two logarithm of the maximum window 77817651Speter size (the size of the history buffer). It should be in the range 8..15 for 779205471Sdelphij this version of the library. The default value is 15 if inflateInit is used 780205471Sdelphij instead. windowBits must be greater than or equal to the windowBits value 781131377Stjr provided to deflateInit2() while compressing, or it must be equal to 15 if 782205471Sdelphij deflateInit2() was not used. If a compressed stream with a larger window 783131377Stjr size is given as input, inflate() will return with the error code 784131377Stjr Z_DATA_ERROR instead of trying to allocate a larger window. 78517651Speter 786205471Sdelphij windowBits can also be zero to request that inflate use the window size in 787205471Sdelphij the zlib header of the compressed stream. 788205471Sdelphij 789205471Sdelphij windowBits can also be -8..-15 for raw inflate. In this case, -windowBits 790205471Sdelphij determines the window size. inflate() will then process raw deflate data, 791131377Stjr not looking for a zlib or gzip header, not generating a check value, and not 792205471Sdelphij looking for any check values for comparison at the end of the stream. This 793131377Stjr is for use with other formats that use the deflate compressed data format 794205471Sdelphij such as zip. Those formats provide their own check values. If a custom 795131377Stjr format is developed using the raw deflate format for compressed data, it is 796131377Stjr recommended that a check value such as an adler32 or a crc32 be applied to 797131377Stjr the uncompressed data as is done in the zlib, gzip, and zip formats. For 798205471Sdelphij most applications, the zlib format should be used as is. Note that comments 799131377Stjr above on the use in deflateInit2() applies to the magnitude of windowBits. 800131377Stjr 801205471Sdelphij windowBits can also be greater than 15 for optional gzip decoding. Add 802131377Stjr 32 to windowBits to enable zlib and gzip decoding with automatic header 803131377Stjr detection, or add 16 to decode only the gzip format (the zlib format will 804205471Sdelphij return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a 805205471Sdelphij crc32 instead of an adler32. 806131377Stjr 807131377Stjr inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 808205471Sdelphij memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 809205471Sdelphij version assumed by the caller, or Z_STREAM_ERROR if the parameters are 810205471Sdelphij invalid, such as a null pointer to the structure. msg is set to null if 811205471Sdelphij there is no error message. inflateInit2 does not perform any decompression 812205471Sdelphij apart from possibly reading the zlib header if present: actual decompression 813205471Sdelphij will be done by inflate(). (So next_in and avail_in may be modified, but 814205471Sdelphij next_out and avail_out are unused and unchanged.) The current implementation 815205471Sdelphij of inflateInit2() does not process any header information -- that is 816205471Sdelphij deferred until inflate() is called. 81717651Speter*/ 81817651Speter 81942468SpeterZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, 82042468Speter const Bytef *dictionary, 82142468Speter uInt dictLength)); 82217651Speter/* 82333904Ssteve Initializes the decompression dictionary from the given uncompressed byte 824205471Sdelphij sequence. This function must be called immediately after a call of inflate, 825205471Sdelphij if that call returned Z_NEED_DICT. The dictionary chosen by the compressor 826157043Sdes can be determined from the adler32 value returned by that call of inflate. 827157043Sdes The compressor and decompressor must use exactly the same dictionary (see 828237410Sdelphij deflateSetDictionary). For raw inflate, this function can be called at any 829237410Sdelphij time to set the dictionary. If the provided dictionary is smaller than the 830237410Sdelphij window and there is already data in the window, then the provided dictionary 831237410Sdelphij will amend what's there. The application must insure that the dictionary 832237410Sdelphij that was used for compression is provided. 83317651Speter 83417651Speter inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a 835205471Sdelphij parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is 83617651Speter inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the 837205471Sdelphij expected one (incorrect adler32 value). inflateSetDictionary does not 83817651Speter perform any decompression: this will be done by subsequent calls of 83917651Speter inflate(). 84017651Speter*/ 84117651Speter 842250261SdelphijZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm, 843250261Sdelphij Bytef *dictionary, 844250261Sdelphij uInt *dictLength)); 845250261Sdelphij/* 846250261Sdelphij Returns the sliding dictionary being maintained by inflate. dictLength is 847250261Sdelphij set to the number of bytes in the dictionary, and that many bytes are copied 848250261Sdelphij to dictionary. dictionary must have enough space, where 32768 bytes is 849250261Sdelphij always enough. If inflateGetDictionary() is called with dictionary equal to 850250261Sdelphij Z_NULL, then only the dictionary length is returned, and nothing is copied. 851250261Sdelphij Similary, if dictLength is Z_NULL, then it is not set. 852250261Sdelphij 853250261Sdelphij inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the 854250261Sdelphij stream state is inconsistent. 855250261Sdelphij*/ 856250261Sdelphij 85742468SpeterZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); 858131377Stjr/* 859237410Sdelphij Skips invalid compressed data until a possible full flush point (see above 860237410Sdelphij for the description of deflate with Z_FULL_FLUSH) can be found, or until all 861205471Sdelphij available input is skipped. No output is provided. 86217651Speter 863237410Sdelphij inflateSync searches for a 00 00 FF FF pattern in the compressed data. 864249582Sgabor All full flush points have this pattern, but not all occurrences of this 865237410Sdelphij pattern are full flush points. 866237410Sdelphij 867237410Sdelphij inflateSync returns Z_OK if a possible full flush point has been found, 868237410Sdelphij Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point 869237410Sdelphij has been found, or Z_STREAM_ERROR if the stream structure was inconsistent. 870237410Sdelphij In the success case, the application may save the current current value of 871237410Sdelphij total_in which indicates where valid compressed data was found. In the 872237410Sdelphij error case, the application may repeatedly call inflateSync, providing more 873237410Sdelphij input each time, until success or end of the input data. 87417651Speter*/ 87517651Speter 876131377StjrZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, 877131377Stjr z_streamp source)); 878131377Stjr/* 879131377Stjr Sets the destination stream as a complete copy of the source stream. 880131377Stjr 881131377Stjr This function can be useful when randomly accessing a large stream. The 882131377Stjr first pass through the stream can periodically record the inflate state, 883131377Stjr allowing restarting inflate at those points when randomly accessing the 884131377Stjr stream. 885131377Stjr 886131377Stjr inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 887131377Stjr enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 888205471Sdelphij (such as zalloc being Z_NULL). msg is left unchanged in both source and 889131377Stjr destination. 890131377Stjr*/ 891131377Stjr 89242468SpeterZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); 89317651Speter/* 89417651Speter This function is equivalent to inflateEnd followed by inflateInit, 895205471Sdelphij but does not free and reallocate all the internal decompression state. The 896205471Sdelphij stream will keep attributes that may have been set by inflateInit2. 89717651Speter 898205471Sdelphij inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 899205471Sdelphij stream state was inconsistent (such as zalloc or state being Z_NULL). 90017651Speter*/ 90117651Speter 902205471SdelphijZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, 903205471Sdelphij int windowBits)); 904205471Sdelphij/* 905205471Sdelphij This function is the same as inflateReset, but it also permits changing 906205471Sdelphij the wrap and window size requests. The windowBits parameter is interpreted 907205471Sdelphij the same as it is for inflateInit2. 908205471Sdelphij 909205471Sdelphij inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source 910205471Sdelphij stream state was inconsistent (such as zalloc or state being Z_NULL), or if 911205471Sdelphij the windowBits parameter is invalid. 912205471Sdelphij*/ 913205471Sdelphij 914157043SdesZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, 915157043Sdes int bits, 916157043Sdes int value)); 917131377Stjr/* 918157043Sdes This function inserts bits in the inflate input stream. The intent is 919205471Sdelphij that this function is used to start inflating at a bit position in the 920205471Sdelphij middle of a byte. The provided bits will be used before any bytes are used 921205471Sdelphij from next_in. This function should only be used with raw inflate, and 922205471Sdelphij should be used before the first inflate() call after inflateInit2() or 923205471Sdelphij inflateReset(). bits must be less than or equal to 16, and that many of the 924205471Sdelphij least significant bits of value will be inserted in the input. 925157043Sdes 926205471Sdelphij If bits is negative, then the input stream bit buffer is emptied. Then 927205471Sdelphij inflatePrime() can be called again to put bits in the buffer. This is used 928205471Sdelphij to clear out bits leftover after feeding inflate a block description prior 929205471Sdelphij to feeding inflate codes. 930205471Sdelphij 931205471Sdelphij inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source 932157043Sdes stream state was inconsistent. 933157043Sdes*/ 934157043Sdes 935205471SdelphijZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); 936205471Sdelphij/* 937205471Sdelphij This function returns two values, one in the lower 16 bits of the return 938205471Sdelphij value, and the other in the remaining upper bits, obtained by shifting the 939205471Sdelphij return value down 16 bits. If the upper value is -1 and the lower value is 940205471Sdelphij zero, then inflate() is currently decoding information outside of a block. 941205471Sdelphij If the upper value is -1 and the lower value is non-zero, then inflate is in 942205471Sdelphij the middle of a stored block, with the lower value equaling the number of 943205471Sdelphij bytes from the input remaining to copy. If the upper value is not -1, then 944205471Sdelphij it is the number of bits back from the current bit position in the input of 945205471Sdelphij the code (literal or length/distance pair) currently being processed. In 946205471Sdelphij that case the lower value is the number of bytes already emitted for that 947205471Sdelphij code. 948205471Sdelphij 949205471Sdelphij A code is being processed if inflate is waiting for more input to complete 950205471Sdelphij decoding of the code, or if it has completed decoding but is waiting for 951205471Sdelphij more output space to write the literal or match data. 952205471Sdelphij 953205471Sdelphij inflateMark() is used to mark locations in the input data for random 954205471Sdelphij access, which may be at bit positions, and to note those cases where the 955205471Sdelphij output of a code may span boundaries of random access blocks. The current 956205471Sdelphij location in the input stream can be determined from avail_in and data_type 957205471Sdelphij as noted in the description for the Z_BLOCK flush parameter for inflate. 958205471Sdelphij 959205471Sdelphij inflateMark returns the value noted above or -1 << 16 if the provided 960205471Sdelphij source stream state was inconsistent. 961205471Sdelphij*/ 962205471Sdelphij 963157043SdesZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, 964157043Sdes gz_headerp head)); 965157043Sdes/* 966205471Sdelphij inflateGetHeader() requests that gzip header information be stored in the 967157043Sdes provided gz_header structure. inflateGetHeader() may be called after 968157043Sdes inflateInit2() or inflateReset(), and before the first call of inflate(). 969157043Sdes As inflate() processes the gzip stream, head->done is zero until the header 970157043Sdes is completed, at which time head->done is set to one. If a zlib stream is 971157043Sdes being decoded, then head->done is set to -1 to indicate that there will be 972205471Sdelphij no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be 973205471Sdelphij used to force inflate() to return immediately after header processing is 974205471Sdelphij complete and before any actual data is decompressed. 975157043Sdes 976205471Sdelphij The text, time, xflags, and os fields are filled in with the gzip header 977157043Sdes contents. hcrc is set to true if there is a header CRC. (The header CRC 978205471Sdelphij was valid if done is set to one.) If extra is not Z_NULL, then extra_max 979157043Sdes contains the maximum number of bytes to write to extra. Once done is true, 980157043Sdes extra_len contains the actual extra field length, and extra contains the 981157043Sdes extra field, or that field truncated if extra_max is less than extra_len. 982157043Sdes If name is not Z_NULL, then up to name_max characters are written there, 983157043Sdes terminated with a zero unless the length is greater than name_max. If 984157043Sdes comment is not Z_NULL, then up to comm_max characters are written there, 985205471Sdelphij terminated with a zero unless the length is greater than comm_max. When any 986205471Sdelphij of extra, name, or comment are not Z_NULL and the respective field is not 987205471Sdelphij present in the header, then that field is set to Z_NULL to signal its 988157043Sdes absence. This allows the use of deflateSetHeader() with the returned 989157043Sdes structure to duplicate the header. However if those fields are set to 990157043Sdes allocated memory, then the application will need to save those pointers 991157043Sdes elsewhere so that they can be eventually freed. 992157043Sdes 993205471Sdelphij If inflateGetHeader is not used, then the header information is simply 994157043Sdes discarded. The header is always checked for validity, including the header 995157043Sdes CRC if present. inflateReset() will reset the process to discard the header 996157043Sdes information. The application would need to call inflateGetHeader() again to 997157043Sdes retrieve the header from the next gzip stream. 998157043Sdes 999205471Sdelphij inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 1000157043Sdes stream state was inconsistent. 1001157043Sdes*/ 1002157043Sdes 1003157043Sdes/* 1004157043SdesZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, 1005131377Stjr unsigned char FAR *window)); 100617651Speter 1007131377Stjr Initialize the internal stream state for decompression using inflateBack() 1008131377Stjr calls. The fields zalloc, zfree and opaque in strm must be initialized 1009131377Stjr before the call. If zalloc and zfree are Z_NULL, then the default library- 1010131377Stjr derived memory allocation routines are used. windowBits is the base two 1011131377Stjr logarithm of the window size, in the range 8..15. window is a caller 1012131377Stjr supplied buffer of that size. Except for special applications where it is 1013131377Stjr assured that deflate was used with small window sizes, windowBits must be 15 1014131377Stjr and a 32K byte window must be supplied to be able to decompress general 1015131377Stjr deflate streams. 1016131377Stjr 1017131377Stjr See inflateBack() for the usage of these routines. 1018131377Stjr 1019131377Stjr inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of 1020237410Sdelphij the parameters are invalid, Z_MEM_ERROR if the internal state could not be 1021205471Sdelphij allocated, or Z_VERSION_ERROR if the version of the library does not match 1022205471Sdelphij the version of the header file. 1023131377Stjr*/ 1024131377Stjr 1025250261Sdelphijtypedef unsigned (*in_func) OF((void FAR *, 1026250261Sdelphij z_const unsigned char FAR * FAR *)); 1027131377Stjrtypedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); 1028131377Stjr 1029157043SdesZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, 1030131377Stjr in_func in, void FAR *in_desc, 1031131377Stjr out_func out, void FAR *out_desc)); 1032131377Stjr/* 1033131377Stjr inflateBack() does a raw inflate with a single call using a call-back 1034250261Sdelphij interface for input and output. This is potentially more efficient than 1035250261Sdelphij inflate() for file i/o applications, in that it avoids copying between the 1036250261Sdelphij output and the sliding window by simply making the window itself the output 1037250261Sdelphij buffer. inflate() can be faster on modern CPUs when used with large 1038250261Sdelphij buffers. inflateBack() trusts the application to not change the output 1039250261Sdelphij buffer passed by the output function, at least until inflateBack() returns. 1040131377Stjr 1041131377Stjr inflateBackInit() must be called first to allocate the internal state 1042131377Stjr and to initialize the state with the user-provided window buffer. 1043131377Stjr inflateBack() may then be used multiple times to inflate a complete, raw 1044205471Sdelphij deflate stream with each call. inflateBackEnd() is then called to free the 1045205471Sdelphij allocated state. 1046131377Stjr 1047131377Stjr A raw deflate stream is one with no zlib or gzip header or trailer. 1048131377Stjr This routine would normally be used in a utility that reads zip or gzip 1049131377Stjr files and writes out uncompressed files. The utility would decode the 1050205471Sdelphij header and process the trailer on its own, hence this routine expects only 1051205471Sdelphij the raw deflate stream to decompress. This is different from the normal 1052205471Sdelphij behavior of inflate(), which expects either a zlib or gzip header and 1053131377Stjr trailer around the deflate stream. 1054131377Stjr 1055131377Stjr inflateBack() uses two subroutines supplied by the caller that are then 1056131377Stjr called by inflateBack() for input and output. inflateBack() calls those 1057131377Stjr routines until it reads a complete deflate stream and writes out all of the 1058131377Stjr uncompressed data, or until it encounters an error. The function's 1059131377Stjr parameters and return types are defined above in the in_func and out_func 1060131377Stjr typedefs. inflateBack() will call in(in_desc, &buf) which should return the 1061131377Stjr number of bytes of provided input, and a pointer to that input in buf. If 1062131377Stjr there is no input available, in() must return zero--buf is ignored in that 1063131377Stjr case--and inflateBack() will return a buffer error. inflateBack() will call 1064131377Stjr out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() 1065131377Stjr should return zero on success, or non-zero on failure. If out() returns 1066131377Stjr non-zero, inflateBack() will return with an error. Neither in() nor out() 1067131377Stjr are permitted to change the contents of the window provided to 1068131377Stjr inflateBackInit(), which is also the buffer that out() uses to write from. 1069131377Stjr The length written by out() will be at most the window size. Any non-zero 1070131377Stjr amount of input may be provided by in(). 1071131377Stjr 1072131377Stjr For convenience, inflateBack() can be provided input on the first call by 1073131377Stjr setting strm->next_in and strm->avail_in. If that input is exhausted, then 1074131377Stjr in() will be called. Therefore strm->next_in must be initialized before 1075131377Stjr calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called 1076131377Stjr immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in 1077131377Stjr must also be initialized, and then if strm->avail_in is not zero, input will 1078205471Sdelphij initially be taken from strm->next_in[0 .. strm->avail_in - 1]. 1079131377Stjr 1080131377Stjr The in_desc and out_desc parameters of inflateBack() is passed as the 1081131377Stjr first parameter of in() and out() respectively when they are called. These 1082131377Stjr descriptors can be optionally used to pass any information that the caller- 1083131377Stjr supplied in() and out() functions need to do their job. 1084131377Stjr 1085131377Stjr On return, inflateBack() will set strm->next_in and strm->avail_in to 1086131377Stjr pass back any unused input that was provided by the last in() call. The 1087131377Stjr return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR 1088205471Sdelphij if in() or out() returned an error, Z_DATA_ERROR if there was a format error 1089205471Sdelphij in the deflate stream (in which case strm->msg is set to indicate the nature 1090205471Sdelphij of the error), or Z_STREAM_ERROR if the stream was not properly initialized. 1091205471Sdelphij In the case of Z_BUF_ERROR, an input or output error can be distinguished 1092205471Sdelphij using strm->next_in which will be Z_NULL only if in() returned an error. If 1093205471Sdelphij strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning 1094205471Sdelphij non-zero. (in() will always be called before out(), so strm->next_in is 1095205471Sdelphij assured to be defined if out() returns non-zero.) Note that inflateBack() 1096205471Sdelphij cannot return Z_OK. 1097131377Stjr*/ 1098131377Stjr 1099157043SdesZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); 1100131377Stjr/* 1101131377Stjr All memory allocated by inflateBackInit() is freed. 1102131377Stjr 1103131377Stjr inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream 1104131377Stjr state was inconsistent. 1105131377Stjr*/ 1106131377Stjr 1107131377StjrZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); 1108131377Stjr/* Return flags indicating compile-time options. 1109131377Stjr 1110131377Stjr Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: 1111131377Stjr 1.0: size of uInt 1112131377Stjr 3.2: size of uLong 1113131377Stjr 5.4: size of voidpf (pointer) 1114131377Stjr 7.6: size of z_off_t 1115131377Stjr 1116131377Stjr Compiler, assembler, and debug options: 1117131377Stjr 8: DEBUG 1118131377Stjr 9: ASMV or ASMINF -- use ASM code 1119131377Stjr 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention 1120131377Stjr 11: 0 (reserved) 1121131377Stjr 1122131377Stjr One-time table building (smaller code, but not thread-safe if true): 1123131377Stjr 12: BUILDFIXED -- build static block decoding tables when needed 1124131377Stjr 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed 1125131377Stjr 14,15: 0 (reserved) 1126131377Stjr 1127131377Stjr Library content (indicates missing functionality): 1128131377Stjr 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking 1129131377Stjr deflate code when not needed) 1130131377Stjr 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect 1131131377Stjr and decode gzip streams (to avoid linking crc code) 1132131377Stjr 18-19: 0 (reserved) 1133131377Stjr 1134131377Stjr Operation variations (changes in library functionality): 1135131377Stjr 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate 1136131377Stjr 21: FASTEST -- deflate algorithm with only one, lowest compression level 1137131377Stjr 22,23: 0 (reserved) 1138131377Stjr 1139131377Stjr The sprintf variant used by gzprintf (zero is best): 1140131377Stjr 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format 1141131377Stjr 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! 1142131377Stjr 26: 0 = returns value, 1 = void -- 1 means inferred string length returned 1143131377Stjr 1144131377Stjr Remainder: 1145131377Stjr 27-31: 0 (reserved) 1146131377Stjr */ 1147131377Stjr 1148237410Sdelphij#ifndef Z_SOLO 1149131377Stjr 115017651Speter /* utility functions */ 115117651Speter 115217651Speter/* 1153205471Sdelphij The following utility functions are implemented on top of the basic 1154205471Sdelphij stream-oriented functions. To simplify the interface, some default options 1155205471Sdelphij are assumed (compression level and memory usage, standard memory allocation 1156205471Sdelphij functions). The source code of these utility functions can be modified if 1157205471Sdelphij you need special options. 115817651Speter*/ 115917651Speter 116042468SpeterZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, 116142468Speter const Bytef *source, uLong sourceLen)); 116217651Speter/* 116317651Speter Compresses the source buffer into the destination buffer. sourceLen is 1164205471Sdelphij the byte length of the source buffer. Upon entry, destLen is the total size 1165205471Sdelphij of the destination buffer, which must be at least the value returned by 1166205471Sdelphij compressBound(sourceLen). Upon exit, destLen is the actual size of the 116717651Speter compressed buffer. 1168205471Sdelphij 116917651Speter compress returns Z_OK if success, Z_MEM_ERROR if there was not 117017651Speter enough memory, Z_BUF_ERROR if there was not enough room in the output 117117651Speter buffer. 117217651Speter*/ 117317651Speter 117442468SpeterZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen, 117542468Speter const Bytef *source, uLong sourceLen, 117642468Speter int level)); 117717651Speter/* 1178205471Sdelphij Compresses the source buffer into the destination buffer. The level 117933904Ssteve parameter has the same meaning as in deflateInit. sourceLen is the byte 1180205471Sdelphij length of the source buffer. Upon entry, destLen is the total size of the 1181131377Stjr destination buffer, which must be at least the value returned by 1182205471Sdelphij compressBound(sourceLen). Upon exit, destLen is the actual size of the 1183131377Stjr compressed buffer. 118433904Ssteve 118533904Ssteve compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 118633904Ssteve memory, Z_BUF_ERROR if there was not enough room in the output buffer, 118733904Ssteve Z_STREAM_ERROR if the level parameter is invalid. 118833904Ssteve*/ 118933904Ssteve 1190131377StjrZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); 1191131377Stjr/* 1192131377Stjr compressBound() returns an upper bound on the compressed size after 1193205471Sdelphij compress() or compress2() on sourceLen bytes. It would be used before a 1194205471Sdelphij compress() or compress2() call to allocate the destination buffer. 1195131377Stjr*/ 1196131377Stjr 119742468SpeterZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, 119842468Speter const Bytef *source, uLong sourceLen)); 119933904Ssteve/* 120017651Speter Decompresses the source buffer into the destination buffer. sourceLen is 1201205471Sdelphij the byte length of the source buffer. Upon entry, destLen is the total size 1202205471Sdelphij of the destination buffer, which must be large enough to hold the entire 1203205471Sdelphij uncompressed data. (The size of the uncompressed data must have been saved 1204205471Sdelphij previously by the compressor and transmitted to the decompressor by some 1205205471Sdelphij mechanism outside the scope of this compression library.) Upon exit, destLen 1206205471Sdelphij is the actual size of the uncompressed buffer. 120717651Speter 120817651Speter uncompress returns Z_OK if success, Z_MEM_ERROR if there was not 120917651Speter enough memory, Z_BUF_ERROR if there was not enough room in the output 1210237410Sdelphij buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In 1211237410Sdelphij the case where there is not enough room, uncompress() will fill the output 1212237410Sdelphij buffer with the uncompressed data up to that point. 121317651Speter*/ 121417651Speter 1215205471Sdelphij /* gzip file access functions */ 121617651Speter 121717651Speter/* 1218205471Sdelphij This library supports reading and writing files in gzip (.gz) format with 1219205471Sdelphij an interface similar to that of stdio, using the functions that start with 1220205471Sdelphij "gz". The gzip format is different from the zlib format. gzip is a gzip 1221205471Sdelphij wrapper, documented in RFC 1952, wrapped around a deflate stream. 1222205471Sdelphij*/ 122333904Ssteve 1224237410Sdelphijtypedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */ 1225205471Sdelphij 1226205471Sdelphij/* 1227205471SdelphijZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); 1228205471Sdelphij 1229205471Sdelphij Opens a gzip (.gz) file for reading or writing. The mode parameter is as 1230205471Sdelphij in fopen ("rb" or "wb") but can also include a compression level ("wb9") or 1231205471Sdelphij a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only 1232205471Sdelphij compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F' 1233205471Sdelphij for fixed code compression as in "wb9F". (See the description of 1234237410Sdelphij deflateInit2 for more information about the strategy parameter.) 'T' will 1235237410Sdelphij request transparent writing or appending with no compression and not using 1236237410Sdelphij the gzip format. 1237205471Sdelphij 1238237410Sdelphij "a" can be used instead of "w" to request that the gzip stream that will 1239237410Sdelphij be written be appended to the file. "+" will result in an error, since 1240237410Sdelphij reading and writing to the same gzip file is not supported. The addition of 1241237410Sdelphij "x" when writing will create the file exclusively, which fails if the file 1242237410Sdelphij already exists. On systems that support it, the addition of "e" when 1243237410Sdelphij reading or writing will set the flag to close the file on an execve() call. 1244237410Sdelphij 1245237410Sdelphij These functions, as well as gzip, will read and decode a sequence of gzip 1246237410Sdelphij streams in a file. The append function of gzopen() can be used to create 1247237410Sdelphij such a file. (Also see gzflush() for another way to do this.) When 1248237410Sdelphij appending, gzopen does not test whether the file begins with a gzip stream, 1249237410Sdelphij nor does it look for the end of the gzip streams to begin appending. gzopen 1250237410Sdelphij will simply append a gzip stream to the existing file. 1251237410Sdelphij 125233904Ssteve gzopen can be used to read a file which is not in gzip format; in this 1253237410Sdelphij case gzread will directly read from the file without decompression. When 1254237410Sdelphij reading, this will be detected automatically by looking for the magic two- 1255237410Sdelphij byte gzip header. 125633904Ssteve 1257205471Sdelphij gzopen returns NULL if the file could not be opened, if there was 1258205471Sdelphij insufficient memory to allocate the gzFile state, or if an invalid mode was 1259205471Sdelphij specified (an 'r', 'w', or 'a' was not provided, or '+' was provided). 1260205471Sdelphij errno can be checked to determine if the reason gzopen failed was that the 1261205471Sdelphij file could not be opened. 1262205471Sdelphij*/ 126317651Speter 1264205471SdelphijZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); 126517651Speter/* 1266205471Sdelphij gzdopen associates a gzFile with the file descriptor fd. File descriptors 1267205471Sdelphij are obtained from calls like open, dup, creat, pipe or fileno (if the file 1268205471Sdelphij has been previously opened with fopen). The mode parameter is as in gzopen. 1269205471Sdelphij 1270205471Sdelphij The next call of gzclose on the returned gzFile will also close the file 1271205471Sdelphij descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor 1272205471Sdelphij fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd, 1273205471Sdelphij mode);. The duplicated descriptor should be saved to avoid a leak, since 1274237410Sdelphij gzdopen does not close fd if it fails. If you are using fileno() to get the 1275237410Sdelphij file descriptor from a FILE *, then you will have to use dup() to avoid 1276237410Sdelphij double-close()ing the file descriptor. Both gzclose() and fclose() will 1277237410Sdelphij close the associated file descriptor, so they need to have different file 1278237410Sdelphij descriptors. 1279205471Sdelphij 1280205471Sdelphij gzdopen returns NULL if there was insufficient memory to allocate the 1281205471Sdelphij gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not 1282205471Sdelphij provided, or '+' was provided), or if fd is -1. The file descriptor is not 1283205471Sdelphij used until the next gz* read, write, seek, or close operation, so gzdopen 1284205471Sdelphij will not detect if fd is invalid (unless fd is -1). 128517651Speter*/ 128617651Speter 1287205471SdelphijZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); 1288205471Sdelphij/* 1289205471Sdelphij Set the internal buffer size used by this library's functions. The 1290205471Sdelphij default buffer size is 8192 bytes. This function must be called after 1291205471Sdelphij gzopen() or gzdopen(), and before any other calls that read or write the 1292205471Sdelphij file. The buffer memory allocation is always deferred to the first read or 1293205471Sdelphij write. Two buffers are allocated, either both of the specified size when 1294205471Sdelphij writing, or one of the specified size and the other twice that size when 1295205471Sdelphij reading. A larger buffer size of, for example, 64K or 128K bytes will 1296205471Sdelphij noticeably increase the speed of decompression (reading). 1297205471Sdelphij 1298205471Sdelphij The new buffer size also affects the maximum length for gzprintf(). 1299205471Sdelphij 1300205471Sdelphij gzbuffer() returns 0 on success, or -1 on failure, such as being called 1301205471Sdelphij too late. 1302205471Sdelphij*/ 1303205471Sdelphij 130442468SpeterZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); 130517651Speter/* 1306205471Sdelphij Dynamically update the compression level or strategy. See the description 130733904Ssteve of deflateInit2 for the meaning of these parameters. 1308205471Sdelphij 130933904Ssteve gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not 131033904Ssteve opened for writing. 131133904Ssteve*/ 131233904Ssteve 1313205471SdelphijZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); 131433904Ssteve/* 1315205471Sdelphij Reads the given number of uncompressed bytes from the compressed file. If 1316237410Sdelphij the input file is not in gzip format, gzread copies the given number of 1317237410Sdelphij bytes into the buffer directly from the file. 131817651Speter 1319205471Sdelphij After reaching the end of a gzip stream in the input, gzread will continue 1320237410Sdelphij to read, looking for another gzip stream. Any number of gzip streams may be 1321237410Sdelphij concatenated in the input file, and will all be decompressed by gzread(). 1322237410Sdelphij If something other than a gzip stream is encountered after a gzip stream, 1323237410Sdelphij that remaining trailing garbage is ignored (and no error is returned). 1324205471Sdelphij 1325237410Sdelphij gzread can be used to read a gzip file that is being concurrently written. 1326237410Sdelphij Upon reaching the end of the input, gzread will return with the available 1327237410Sdelphij data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then 1328237410Sdelphij gzclearerr can be used to clear the end of file indicator in order to permit 1329237410Sdelphij gzread to be tried again. Z_OK indicates that a gzip stream was completed 1330237410Sdelphij on the last gzread. Z_BUF_ERROR indicates that the input file ended in the 1331237410Sdelphij middle of a gzip stream. Note that gzread does not return -1 in the event 1332237410Sdelphij of an incomplete gzip stream. This error is deferred until gzclose(), which 1333237410Sdelphij will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip 1334237410Sdelphij stream. Alternatively, gzerror can be used before gzclose to detect this 1335237410Sdelphij case. 1336237410Sdelphij 1337205471Sdelphij gzread returns the number of uncompressed bytes actually read, less than 1338205471Sdelphij len for end of file, or -1 for error. 1339205471Sdelphij*/ 1340205471Sdelphij 1341205471SdelphijZEXTERN int ZEXPORT gzwrite OF((gzFile file, 1342205471Sdelphij voidpc buf, unsigned len)); 134317651Speter/* 134417651Speter Writes the given number of uncompressed bytes into the compressed file. 1345205471Sdelphij gzwrite returns the number of uncompressed bytes written or 0 in case of 1346205471Sdelphij error. 134717651Speter*/ 134817651Speter 1349237410SdelphijZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...)); 135017651Speter/* 1351205471Sdelphij Converts, formats, and writes the arguments to the compressed file under 1352205471Sdelphij control of the format string, as in fprintf. gzprintf returns the number of 1353205471Sdelphij uncompressed bytes actually written, or 0 in case of error. The number of 1354205471Sdelphij uncompressed bytes written is limited to 8191, or one less than the buffer 1355205471Sdelphij size given to gzbuffer(). The caller should assure that this limit is not 1356205471Sdelphij exceeded. If it is exceeded, then gzprintf() will return an error (0) with 1357205471Sdelphij nothing written. In this case, there may also be a buffer overflow with 1358205471Sdelphij unpredictable consequences, which is possible only if zlib was compiled with 1359205471Sdelphij the insecure functions sprintf() or vsprintf() because the secure snprintf() 1360205471Sdelphij or vsnprintf() functions were not available. This can be determined using 1361205471Sdelphij zlibCompileFlags(). 136233904Ssteve*/ 136333904Ssteve 136442468SpeterZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); 136533904Ssteve/* 1366205471Sdelphij Writes the given null-terminated string to the compressed file, excluding 136733904Ssteve the terminating null character. 1368205471Sdelphij 1369205471Sdelphij gzputs returns the number of characters written, or -1 in case of error. 137033904Ssteve*/ 137133904Ssteve 137242468SpeterZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); 137333904Ssteve/* 1374205471Sdelphij Reads bytes from the compressed file until len-1 characters are read, or a 1375205471Sdelphij newline character is read and transferred to buf, or an end-of-file 1376205471Sdelphij condition is encountered. If any characters are read or if len == 1, the 1377205471Sdelphij string is terminated with a null character. If no characters are read due 1378205471Sdelphij to an end-of-file or len < 1, then the buffer is left untouched. 1379205471Sdelphij 1380205471Sdelphij gzgets returns buf which is a null-terminated string, or it returns NULL 1381205471Sdelphij for end-of-file or in case of error. If there was an error, the contents at 1382205471Sdelphij buf are indeterminate. 138333904Ssteve*/ 138433904Ssteve 1385205471SdelphijZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); 138633904Ssteve/* 1387205471Sdelphij Writes c, converted to an unsigned char, into the compressed file. gzputc 1388205471Sdelphij returns the value that was written, or -1 in case of error. 138933904Ssteve*/ 139033904Ssteve 1391205471SdelphijZEXTERN int ZEXPORT gzgetc OF((gzFile file)); 139233904Ssteve/* 1393205471Sdelphij Reads one byte from the compressed file. gzgetc returns this byte or -1 1394237410Sdelphij in case of end of file or error. This is implemented as a macro for speed. 1395237410Sdelphij As such, it does not do all of the checking the other functions do. I.e. 1396237410Sdelphij it does not check to see if file is NULL, nor whether the structure file 1397237410Sdelphij points to has been clobbered or not. 139833904Ssteve*/ 139933904Ssteve 1400205471SdelphijZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); 1401131377Stjr/* 1402205471Sdelphij Push one character back onto the stream to be read as the first character 1403205471Sdelphij on the next read. At least one character of push-back is allowed. 1404205471Sdelphij gzungetc() returns the character pushed, or -1 on failure. gzungetc() will 1405205471Sdelphij fail if c is -1, and may fail if a character has been pushed but not read 1406205471Sdelphij yet. If gzungetc is used immediately after gzopen or gzdopen, at least the 1407205471Sdelphij output buffer size of pushed characters is allowed. (See gzbuffer above.) 1408205471Sdelphij The pushed character will be discarded if the stream is repositioned with 1409205471Sdelphij gzseek() or gzrewind(). 1410131377Stjr*/ 1411131377Stjr 1412205471SdelphijZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); 141333904Ssteve/* 1414205471Sdelphij Flushes all pending output into the compressed file. The parameter flush 1415205471Sdelphij is as in the deflate() function. The return value is the zlib error number 1416205471Sdelphij (see function gzerror below). gzflush is only permitted when writing. 1417205471Sdelphij 1418205471Sdelphij If the flush parameter is Z_FINISH, the remaining data is written and the 1419205471Sdelphij gzip stream is completed in the output. If gzwrite() is called again, a new 1420205471Sdelphij gzip stream will be started in the output. gzread() is able to read such 1421205471Sdelphij concatented gzip streams. 1422205471Sdelphij 1423205471Sdelphij gzflush should be called only when strictly necessary because it will 1424205471Sdelphij degrade compression if called too often. 142517651Speter*/ 142617651Speter 1427131377Stjr/* 1428205471SdelphijZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, 1429205471Sdelphij z_off_t offset, int whence)); 1430205471Sdelphij 1431205471Sdelphij Sets the starting position for the next gzread or gzwrite on the given 1432205471Sdelphij compressed file. The offset represents a number of bytes in the 1433205471Sdelphij uncompressed data stream. The whence parameter is defined as in lseek(2); 143433904Ssteve the value SEEK_END is not supported. 1435205471Sdelphij 143633904Ssteve If the file is opened for reading, this function is emulated but can be 1437205471Sdelphij extremely slow. If the file is opened for writing, only forward seeks are 143833904Ssteve supported; gzseek then compresses a sequence of zeroes up to the new 143933904Ssteve starting position. 144033904Ssteve 1441205471Sdelphij gzseek returns the resulting offset location as measured in bytes from 144233904Ssteve the beginning of the uncompressed stream, or -1 in case of error, in 144333904Ssteve particular if the file is opened for writing and the new starting position 144433904Ssteve would be before the current position. 144533904Ssteve*/ 144633904Ssteve 144742468SpeterZEXTERN int ZEXPORT gzrewind OF((gzFile file)); 144817651Speter/* 144933904Ssteve Rewinds the given file. This function is supported only for reading. 145033904Ssteve 1451205471Sdelphij gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) 145233904Ssteve*/ 145333904Ssteve 1454205471Sdelphij/* 145542468SpeterZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); 1456205471Sdelphij 1457205471Sdelphij Returns the starting position for the next gzread or gzwrite on the given 1458205471Sdelphij compressed file. This position represents a number of bytes in the 1459205471Sdelphij uncompressed data stream, and is zero when starting, even if appending or 1460205471Sdelphij reading a gzip stream from the middle of a file using gzdopen(). 1461205471Sdelphij 1462205471Sdelphij gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) 1463205471Sdelphij*/ 1464205471Sdelphij 146533904Ssteve/* 1466205471SdelphijZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); 146733904Ssteve 1468205471Sdelphij Returns the current offset in the file being read or written. This offset 1469205471Sdelphij includes the count of bytes that precede the gzip stream, for example when 1470205471Sdelphij appending or when using gzdopen() for reading. When reading, the offset 1471205471Sdelphij does not include as yet unused buffered input. This information can be used 1472205471Sdelphij for a progress indicator. On error, gzoffset() returns -1. 147333904Ssteve*/ 147433904Ssteve 147542468SpeterZEXTERN int ZEXPORT gzeof OF((gzFile file)); 147633904Ssteve/* 1477205471Sdelphij Returns true (1) if the end-of-file indicator has been set while reading, 1478205471Sdelphij false (0) otherwise. Note that the end-of-file indicator is set only if the 1479205471Sdelphij read tried to go past the end of the input, but came up short. Therefore, 1480205471Sdelphij just like feof(), gzeof() may return false even if there is no more data to 1481205471Sdelphij read, in the event that the last read request was for the exact number of 1482205471Sdelphij bytes remaining in the input file. This will happen if the input file size 1483205471Sdelphij is an exact multiple of the buffer size. 1484205471Sdelphij 1485205471Sdelphij If gzeof() returns true, then the read functions will return no more data, 1486205471Sdelphij unless the end-of-file indicator is reset by gzclearerr() and the input file 1487205471Sdelphij has grown since the previous end of file was detected. 148833904Ssteve*/ 148933904Ssteve 1490157043SdesZEXTERN int ZEXPORT gzdirect OF((gzFile file)); 1491157043Sdes/* 1492205471Sdelphij Returns true (1) if file is being copied directly while reading, or false 1493237410Sdelphij (0) if file is a gzip stream being decompressed. 1494205471Sdelphij 1495205471Sdelphij If the input file is empty, gzdirect() will return true, since the input 1496205471Sdelphij does not contain a gzip stream. 1497205471Sdelphij 1498205471Sdelphij If gzdirect() is used immediately after gzopen() or gzdopen() it will 1499205471Sdelphij cause buffers to be allocated to allow reading the file to determine if it 1500205471Sdelphij is a gzip file. Therefore if gzbuffer() is used, it should be called before 1501205471Sdelphij gzdirect(). 1502237410Sdelphij 1503237410Sdelphij When writing, gzdirect() returns true (1) if transparent writing was 1504237410Sdelphij requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note: 1505237410Sdelphij gzdirect() is not needed when writing. Transparent writing must be 1506237410Sdelphij explicitly requested, so the application already knows the answer. When 1507237410Sdelphij linking statically, using gzdirect() will include all of the zlib code for 1508237410Sdelphij gzip file reading and decompression, which may not be desired.) 1509157043Sdes*/ 1510157043Sdes 151142468SpeterZEXTERN int ZEXPORT gzclose OF((gzFile file)); 151233904Ssteve/* 1513205471Sdelphij Flushes all pending output if necessary, closes the compressed file and 1514205471Sdelphij deallocates the (de)compression state. Note that once file is closed, you 1515205471Sdelphij cannot call gzerror with file, since its structures have been deallocated. 1516205471Sdelphij gzclose must not be called more than once on the same file, just as free 1517205471Sdelphij must not be called more than once on the same allocation. 1518205471Sdelphij 1519205471Sdelphij gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a 1520237410Sdelphij file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the 1521237410Sdelphij last read ended in the middle of a gzip stream, or Z_OK on success. 152217651Speter*/ 152317651Speter 1524205471SdelphijZEXTERN int ZEXPORT gzclose_r OF((gzFile file)); 1525205471SdelphijZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); 1526205471Sdelphij/* 1527205471Sdelphij Same as gzclose(), but gzclose_r() is only for use when reading, and 1528205471Sdelphij gzclose_w() is only for use when writing or appending. The advantage to 1529205471Sdelphij using these instead of gzclose() is that they avoid linking in zlib 1530205471Sdelphij compression or decompression code that is not used when only reading or only 1531205471Sdelphij writing respectively. If gzclose() is used, then both compression and 1532205471Sdelphij decompression code will be included the application when linking to a static 1533205471Sdelphij zlib library. 1534205471Sdelphij*/ 1535205471Sdelphij 153642468SpeterZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); 153717651Speter/* 1538205471Sdelphij Returns the error message for the last error which occurred on the given 1539205471Sdelphij compressed file. errnum is set to zlib error number. If an error occurred 1540205471Sdelphij in the file system and not in the compression library, errnum is set to 1541205471Sdelphij Z_ERRNO and the application may consult errno to get the exact error code. 1542205471Sdelphij 1543205471Sdelphij The application must not modify the returned string. Future calls to 1544205471Sdelphij this function may invalidate the previously returned string. If file is 1545205471Sdelphij closed, then the string previously returned by gzerror will no longer be 1546205471Sdelphij available. 1547205471Sdelphij 1548205471Sdelphij gzerror() should be used to distinguish errors from end-of-file for those 1549205471Sdelphij functions above that do not distinguish those cases in their return values. 155017651Speter*/ 155117651Speter 1552131377StjrZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); 1553131377Stjr/* 1554205471Sdelphij Clears the error and end-of-file flags for file. This is analogous to the 1555205471Sdelphij clearerr() function in stdio. This is useful for continuing to read a gzip 1556131377Stjr file that is being written concurrently. 1557131377Stjr*/ 1558131377Stjr 1559237410Sdelphij#endif /* !Z_SOLO */ 1560205471Sdelphij 156117651Speter /* checksum functions */ 156217651Speter 156317651Speter/* 156417651Speter These functions are not related to compression but are exported 1565205471Sdelphij anyway because they might be useful in applications using the compression 1566205471Sdelphij library. 156717651Speter*/ 156817651Speter 156942468SpeterZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); 157017651Speter/* 157117651Speter Update a running Adler-32 checksum with the bytes buf[0..len-1] and 1572205471Sdelphij return the updated checksum. If buf is Z_NULL, this function returns the 1573205471Sdelphij required initial value for the checksum. 157417651Speter 1575205471Sdelphij An Adler-32 checksum is almost as reliable as a CRC32 but can be computed 1576205471Sdelphij much faster. 1577205471Sdelphij 1578205471Sdelphij Usage example: 1579205471Sdelphij 158017651Speter uLong adler = adler32(0L, Z_NULL, 0); 158117651Speter 158217651Speter while (read_buffer(buffer, length) != EOF) { 158317651Speter adler = adler32(adler, buffer, length); 158417651Speter } 158517651Speter if (adler != original_adler) error(); 158617651Speter*/ 158717651Speter 1588205471Sdelphij/* 1589157043SdesZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, 1590157043Sdes z_off_t len2)); 1591205471Sdelphij 1592157043Sdes Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 1593157043Sdes and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for 1594157043Sdes each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of 1595237410Sdelphij seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note 1596237410Sdelphij that the z_off_t type (like off_t) is a signed integer. If len2 is 1597237410Sdelphij negative, the result has no meaning or utility. 1598157043Sdes*/ 1599157043Sdes 160042468SpeterZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); 160117651Speter/* 1602157043Sdes Update a running CRC-32 with the bytes buf[0..len-1] and return the 1603205471Sdelphij updated CRC-32. If buf is Z_NULL, this function returns the required 1604237410Sdelphij initial value for the crc. Pre- and post-conditioning (one's complement) is 1605237410Sdelphij performed within this function so it shouldn't be done by the application. 1606205471Sdelphij 160717651Speter Usage example: 160817651Speter 160917651Speter uLong crc = crc32(0L, Z_NULL, 0); 161017651Speter 161117651Speter while (read_buffer(buffer, length) != EOF) { 161217651Speter crc = crc32(crc, buffer, length); 161317651Speter } 161417651Speter if (crc != original_crc) error(); 161517651Speter*/ 161617651Speter 1617205471Sdelphij/* 1618157043SdesZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); 161917651Speter 1620157043Sdes Combine two CRC-32 check values into one. For two sequences of bytes, 1621157043Sdes seq1 and seq2 with lengths len1 and len2, CRC-32 check values were 1622157043Sdes calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 1623157043Sdes check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and 1624157043Sdes len2. 1625157043Sdes*/ 1626157043Sdes 1627157043Sdes 162817651Speter /* various hacks, don't look :) */ 162917651Speter 163017651Speter/* deflateInit and inflateInit are macros to allow checking the zlib version 163117651Speter * and the compiler's view of z_stream: 163217651Speter */ 163342468SpeterZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, 163433904Ssteve const char *version, int stream_size)); 163542468SpeterZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, 163642468Speter const char *version, int stream_size)); 163742468SpeterZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, 163842468Speter int windowBits, int memLevel, 163942468Speter int strategy, const char *version, 164042468Speter int stream_size)); 164142468SpeterZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, 164242468Speter const char *version, int stream_size)); 1643157043SdesZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, 1644131377Stjr unsigned char FAR *window, 1645131377Stjr const char *version, 1646131377Stjr int stream_size)); 164717651Speter#define deflateInit(strm, level) \ 1648237410Sdelphij deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) 164917651Speter#define inflateInit(strm) \ 1650237410Sdelphij inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream)) 165117651Speter#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ 165217651Speter deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ 1653237410Sdelphij (strategy), ZLIB_VERSION, (int)sizeof(z_stream)) 165417651Speter#define inflateInit2(strm, windowBits) \ 1655237410Sdelphij inflateInit2_((strm), (windowBits), ZLIB_VERSION, \ 1656237410Sdelphij (int)sizeof(z_stream)) 1657131377Stjr#define inflateBackInit(strm, windowBits, window) \ 1658131377Stjr inflateBackInit_((strm), (windowBits), (window), \ 1659237410Sdelphij ZLIB_VERSION, (int)sizeof(z_stream)) 166017651Speter 1661237410Sdelphij#ifndef Z_SOLO 1662237410Sdelphij 1663237410Sdelphij/* gzgetc() macro and its supporting function and exposed data structure. Note 1664237410Sdelphij * that the real internal state is much larger than the exposed structure. 1665237410Sdelphij * This abbreviated structure exposes just enough for the gzgetc() macro. The 1666237410Sdelphij * user should not mess with these exposed elements, since their names or 1667237410Sdelphij * behavior could change in the future, perhaps even capriciously. They can 1668237410Sdelphij * only be used by the gzgetc() macro. You have been warned. 1669237410Sdelphij */ 1670237410Sdelphijstruct gzFile_s { 1671237410Sdelphij unsigned have; 1672237410Sdelphij unsigned char *next; 1673237410Sdelphij z_off64_t pos; 1674237410Sdelphij}; 1675237410SdelphijZEXTERN int ZEXPORT gzgetc_ OF((gzFile file)); /* backward compatibility */ 1676237410Sdelphij#ifdef Z_PREFIX_SET 1677237410Sdelphij# undef z_gzgetc 1678237410Sdelphij# define z_gzgetc(g) \ 1679237410Sdelphij ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g)) 1680237410Sdelphij#else 1681237410Sdelphij# define gzgetc(g) \ 1682237410Sdelphij ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : gzgetc(g)) 1683237410Sdelphij#endif 1684237410Sdelphij 1685206708Sdelphij/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or 1686206708Sdelphij * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if 1687206708Sdelphij * both are true, the application gets the *64 functions, and the regular 1688206708Sdelphij * functions are changed to 64 bits) -- in case these are set on systems 1689206708Sdelphij * without large file support, _LFS64_LARGEFILE must also be true 1690206708Sdelphij */ 1691237410Sdelphij#ifdef Z_LARGE64 1692206708Sdelphij ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); 1693206708Sdelphij ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int)); 1694206708Sdelphij ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile)); 1695206708Sdelphij ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile)); 1696206708Sdelphij ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t)); 1697206708Sdelphij ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t)); 1698206708Sdelphij#endif 169933904Ssteve 1700237410Sdelphij#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64) 1701237410Sdelphij# ifdef Z_PREFIX_SET 1702237410Sdelphij# define z_gzopen z_gzopen64 1703237410Sdelphij# define z_gzseek z_gzseek64 1704237410Sdelphij# define z_gztell z_gztell64 1705237410Sdelphij# define z_gzoffset z_gzoffset64 1706237410Sdelphij# define z_adler32_combine z_adler32_combine64 1707237410Sdelphij# define z_crc32_combine z_crc32_combine64 1708237410Sdelphij# else 1709237410Sdelphij# define gzopen gzopen64 1710237410Sdelphij# define gzseek gzseek64 1711237410Sdelphij# define gztell gztell64 1712237410Sdelphij# define gzoffset gzoffset64 1713237410Sdelphij# define adler32_combine adler32_combine64 1714237410Sdelphij# define crc32_combine crc32_combine64 1715237410Sdelphij# endif 1716237410Sdelphij# ifndef Z_LARGE64 1717206708Sdelphij ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); 1718206708Sdelphij ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int)); 1719206708Sdelphij ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile)); 1720206708Sdelphij ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile)); 1721206708Sdelphij ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t)); 1722206708Sdelphij ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t)); 1723206708Sdelphij# endif 1724206708Sdelphij#else 1725205471Sdelphij ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); 1726205471Sdelphij ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int)); 1727205471Sdelphij ZEXTERN z_off_t ZEXPORT gztell OF((gzFile)); 1728205471Sdelphij ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile)); 1729205471Sdelphij ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); 1730205471Sdelphij ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); 1731206708Sdelphij#endif 1732205471Sdelphij 1733237410Sdelphij#else /* Z_SOLO */ 1734237410Sdelphij 1735237410Sdelphij ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); 1736237410Sdelphij ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); 1737237410Sdelphij 1738237410Sdelphij#endif /* !Z_SOLO */ 1739237410Sdelphij 1740206708Sdelphij/* hack for buggy compilers */ 1741131377Stjr#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) 1742206708Sdelphij struct internal_state {int dummy;}; 174317651Speter#endif 174417651Speter 1745206708Sdelphij/* undocumented functions */ 1746145474SkientzleZEXTERN const char * ZEXPORT zError OF((int)); 1747205471SdelphijZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp)); 1748237410SdelphijZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table OF((void)); 1749205471SdelphijZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int)); 1750237410SdelphijZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp)); 1751237410SdelphijZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp)); 1752237410Sdelphij#if defined(_WIN32) && !defined(Z_SOLO) 1753237410SdelphijZEXTERN gzFile ZEXPORT gzopen_w OF((const wchar_t *path, 1754237410Sdelphij const char *mode)); 1755237410Sdelphij#endif 1756250261Sdelphij#if defined(STDC) || defined(Z_HAVE_STDARG_H) 1757250261Sdelphij# ifndef Z_SOLO 1758250261SdelphijZEXTERN int ZEXPORTVA gzvprintf Z_ARG((gzFile file, 1759250261Sdelphij const char *format, 1760250261Sdelphij va_list va)); 1761250261Sdelphij# endif 1762250261Sdelphij#endif 176317651Speter 176417651Speter#ifdef __cplusplus 176517651Speter} 176617651Speter#endif 176717651Speter 1768131377Stjr#endif /* ZLIB_H */ 1769