/* * Copyright (c) 2008 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* zlib.h -- interface of the 'zlib' general purpose compression library * version 1.2.3, July 18th, 2005 * * Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler * * This software is provided 'as-is', without any express or implied * warranty. In no event will the authors be held liable for any damages * arising from the use of this software. * * Permission is granted to anyone to use this software for any purpose, * including commercial applications, and to alter it and redistribute it * freely, subject to the following restrictions: * * 1. The origin of this software must not be misrepresented; you must not * claim that you wrote the original software. If you use this software * in a product, an acknowledgment in the product documentation would be * appreciated but is not required. * 2. Altered source versions must be plainly marked as such, and must not be * misrepresented as being the original software. * 3. This notice may not be removed or altered from any source distribution. * * Jean-loup Gailly Mark Adler * jloup@gzip.org madler@alumni.caltech.edu * * * The data format used by the zlib library is described by RFCs (Request for * Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt * (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). */ #ifndef ZLIB_H #define ZLIB_H #ifdef __cplusplus extern "C" { #endif #include "zconf.h" #define ZLIB_VERSION "1.2.3" #define ZLIB_VERNUM 0x1230 /* * The 'zlib' compression library provides in-memory compression and * decompression functions, including integrity checks of the uncompressed * data. This version of the library supports only one compression method * (deflation) but other algorithms will be added later and will have the same * stream interface. * * Compression can be done in a single step if the buffers are large * enough (for example if an input file is mmap'ed), or can be done by * repeated calls of the compression function. In the latter case, the * application must provide more input and/or consume the output * (providing more output space) before each call. * * The compressed data format used by default by the in-memory functions is * the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped * around a deflate stream, which is itself documented in RFC 1951. * * The library also supports reading and writing files in gzip (.gz) format * with an interface similar to that of stdio using the functions that start * with "gz". The gzip format is different from the zlib format. gzip is a * gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. * * This library can optionally read and write gzip streams in memory as well. * * The zlib format was designed to be compact and fast for use in memory * and on communications channels. The gzip format was designed for single- * file compression on file systems, has a larger header than zlib to maintain * directory information, and uses a different, slower check method than zlib. * * The library does not install any signal handler. The decoder checks * the consistency of the compressed data, so the library should never * crash even in case of corrupted input. */ typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); typedef void (*free_func) OF((voidpf opaque, voidpf address)); struct internal_state; typedef struct z_stream_s { Bytef *next_in;/* next input byte */ uInt avail_in;/* number of bytes available at next_in */ uLong total_in;/* total nb of input bytes read so far */ Bytef *next_out;/* next output byte should be put there */ uInt avail_out;/* remaining free space at next_out */ uLong total_out;/* total nb of bytes output so far */ char *msg; /* last error message, NULL if no error */ struct internal_state FAR *state; /* not visible by applications */ alloc_func zalloc; /* used to allocate the internal state */ free_func zfree;/* used to free the internal state */ voidpf opaque;/* private data object passed to zalloc and zfree */ int data_type;/* best guess about the data type: binary or text */ uLong adler; /* adler32 value of the uncompressed data */ uLong reserved;/* reserved for future use */ } z_stream; typedef z_stream FAR *z_streamp; /* * gzip header information passed to and from zlib routines. See RFC 1952 * for more details on the meanings of these fields. */ typedef struct gz_header_s { int text; /* true if compressed data believed to be text */ uLong time; /* modification time */ int xflags; /* extra flags (not used when writing a gzip file) */ int os; /* operating system */ Bytef *extra; /* pointer to extra field or Z_NULL if none */ uInt extra_len;/* extra field length (valid if extra != Z_NULL) */ uInt extra_max;/* space at extra (only when reading header) */ Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ uInt name_max;/* space at name (only when reading header) */ Bytef *comment;/* pointer to zero-terminated comment or Z_NULL */ uInt comm_max;/* space at comment (only when reading header) */ int hcrc; /* true if there was or will be a header crc */ int done; /* true when done reading gzip header (not used * when writing a gzip file) */ } gz_header; typedef gz_header FAR *gz_headerp; /* * The application must update next_in and avail_in when avail_in has * dropped to zero. It must update next_out and avail_out when avail_out * has dropped to zero. The application must initialize zalloc, zfree and * opaque before calling the init function. All other fields are set by the * compression library and must not be updated by the application. * * The opaque value provided by the application will be passed as the first * parameter for calls of zalloc and zfree. This can be useful for custom * memory management. The compression library attaches no meaning to the * opaque value. * * zalloc must return Z_NULL if there is not enough memory for the object. * If zlib is used in a multi-threaded application, zalloc and zfree must be * thread safe. * * On 16-bit systems, the functions zalloc and zfree must be able to allocate * exactly 65536 bytes, but will not be required to allocate more than this * if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, * pointers returned by zalloc for objects of exactly 65536 bytes *must* * have their offset normalized to zero. The default allocation function * provided by this library ensures this (see zutil.c). To reduce memory * requirements and avoid any allocation of 64K objects, at the expense of * compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). * * The fields total_in and total_out can be used for statistics or * progress reports. After compression, total_in holds the total size of * the uncompressed data and may be saved for use in the decompressor * (particularly if the decompressor wants to decompress everything in * a single step). */ /* constants */ #define Z_NO_FLUSH 0 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ /* 2 is a reserved value (in zlib 1.2.3, Z_PACKET_FLUSH was removed) */ #define Z_SYNC_FLUSH 3 #define Z_FULL_FLUSH 4 #define Z_FINISH 5 #define Z_BLOCK 6 /* Allowed flush values; see deflate() and inflate() below for details */ #define Z_OK 0 #define Z_STREAM_END 1 #define Z_NEED_DICT 2 #define Z_ERRNO (-1) #define Z_STREAM_ERROR (-2) #define Z_DATA_ERROR (-3) #define Z_MEM_ERROR (-4) #define Z_BUF_ERROR (-5) #define Z_VERSION_ERROR (-6) /* Return codes for the compression/decompression functions. Negative * values are errors, positive values are used for special but normal events. */ #define Z_NO_COMPRESSION 0 #define Z_BEST_SPEED 1 #define Z_BEST_COMPRESSION 9 #define Z_DEFAULT_COMPRESSION (-1) /* compression levels */ #define Z_FILTERED 1 #define Z_HUFFMAN_ONLY 2 #define Z_RLE 3 #define Z_FIXED 4 #define Z_DEFAULT_STRATEGY 0 /* compression strategy; see deflateInit2() below for details */ #define Z_BINARY 0 #define Z_TEXT 1 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ #define Z_UNKNOWN 2 /* Possible values of the data_type field (though see inflate()) */ #define Z_DEFLATED 8 /* The deflate compression method (the only one supported in this version) */ #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ #define zlib_version zlibVersion() /* for compatibility with versions < 1.0.2 */ /* basic functions */ ZEXTERN const char * ZEXPORT zlibVersion OF((void)); /* The application can compare zlibVersion and ZLIB_VERSION for consistency. * If the first character differs, the library code actually used is * not compatible with the zlib.h header file used by the application. * This check is automatically made by deflateInit and inflateInit. */ /* * ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); * * Initializes the internal stream state for compression. The fields * zalloc, zfree and opaque must be initialized before by the caller. * If zalloc and zfree are set to Z_NULL, deflateInit updates them to * use default allocation functions. * * The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: * 1 gives best speed, 9 gives best compression, 0 gives no compression at * all (the input data is simply copied a block at a time). * Z_DEFAULT_COMPRESSION requests a default compromise between speed and * compression (currently equivalent to level 6). * * deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not * enough memory, Z_STREAM_ERROR if level is not a valid compression level, * Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible * with the version assumed by the caller (ZLIB_VERSION). * msg is set to null if there is no error message. deflateInit does not * perform any compression: this will be done by deflate(). */ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); /* * deflate compresses as much data as possible, and stops when the input * buffer becomes empty or the output buffer becomes full. It may introduce some * output latency (reading input without producing any output) except when * forced to flush. * * The detailed semantics are as follows. deflate performs one or both of the * following actions: * * - Compress more input starting at next_in and update next_in and avail_in * accordingly. If not all input can be processed (because there is not * enough room in the output buffer), next_in and avail_in are updated and * processing will resume at this point for the next call of deflate(). * * - Provide more output starting at next_out and update next_out and avail_out * accordingly. This action is forced if the parameter flush is non zero. * Forcing flush frequently degrades the compression ratio, so this parameter * should be set only when necessary (in interactive applications). * Some output may be provided even if flush is not set. * * Before the call of deflate(), the application should ensure that at least * one of the actions is possible, by providing more input and/or consuming * more output, and updating avail_in or avail_out accordingly; avail_out * should never be zero before the call. The application can consume the * compressed output when it wants, for example when the output buffer is full * (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK * and with zero avail_out, it must be called again after making room in the * output buffer because there might be more output pending. * * Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to * decide how much data to accumualte before producing output, in order to * maximize compression. * * If the parameter flush is set to Z_SYNC_FLUSH, all pending output is * flushed to the output buffer and the output is aligned on a byte boundary, so * that the decompressor can get all input data available so far. (In particular * avail_in is zero after the call if enough output space has been provided * before the call.) Flushing may degrade compression for some compression * algorithms and so it should be used only when necessary. * * If flush is set to Z_FULL_FLUSH, all output is flushed as with * Z_SYNC_FLUSH, and the compression state is reset so that decompression can * restart from this point if previous compressed data has been damaged or if * random access is desired. Using Z_FULL_FLUSH too often can seriously degrade * compression. * * If deflate returns with avail_out == 0, this function must be called again * with the same value of the flush parameter and more output space (updated * avail_out), until the flush is complete (deflate returns with non-zero * avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that * avail_out is greater than six to avoid repeated flush markers due to * avail_out == 0 on return. * * If the parameter flush is set to Z_FINISH, pending input is processed, * pending output is flushed and deflate returns with Z_STREAM_END if there * was enough output space; if deflate returns with Z_OK, this function must be * called again with Z_FINISH and more output space (updated avail_out) but no * more input data, until it returns with Z_STREAM_END or an error. After * deflate has returned Z_STREAM_END, the only possible operations on the * stream are deflateReset or deflateEnd. * * Z_FINISH can be used immediately after deflateInit if all the compression * is to be done in a single step. In this case, avail_out must be at least * the value returned by deflateBound (see below). If deflate does not return * Z_STREAM_END, then it must be called again as described above. * * deflate() sets strm->adler to the adler32 checksum of all input read * so far (that is, total_in bytes). * * deflate() may update strm->data_type if it can make a good guess about * the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered * binary. This field is only for information purposes and does not affect * the compression algorithm in any manner. * * deflate() returns Z_OK if some progress has been made (more input * processed or more output produced), Z_STREAM_END if all input has been * consumed and all output has been produced (only when flush is set to * Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example * if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible * (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not * fatal, and deflate() can be called again with more input and more output * space to continue compressing. */ ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); /* * All dynamically allocated data structures for this stream are freed. * This function discards any unprocessed input and does not flush any * pending output. * * deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the * stream state was inconsistent, Z_DATA_ERROR if the stream was freed * prematurely (some input or output was discarded). In the error case, * msg may be set but then points to a static string (which must not be * deallocated). */ /* * ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); * * Initializes the internal stream state for decompression. The fields * next_in, avail_in, zalloc, zfree and opaque must be initialized before by * the caller. If next_in is not Z_NULL and avail_in is large enough (the exact * value depends on the compression method), inflateInit determines the * compression method from the zlib header and allocates all data structures * accordingly; otherwise the allocation will be deferred to the first call of * inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to * use default allocation functions. * * inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough * memory, Z_VERSION_ERROR if the zlib library version is incompatible with the * version assumed by the caller. msg is set to null if there is no error * message. inflateInit does not perform any decompression apart from reading * the zlib header if present: this will be done by inflate(). (So next_in and * avail_in may be modified, but next_out and avail_out are unchanged.) */ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); /* * inflate decompresses as much data as possible, and stops when the input * buffer becomes empty or the output buffer becomes full. It may introduce * some output latency (reading input without producing any output) except when * forced to flush. * * The detailed semantics are as follows. inflate performs one or both of the * following actions: * * - Decompress more input starting at next_in and update next_in and avail_in * accordingly. If not all input can be processed (because there is not * enough room in the output buffer), next_in is updated and processing * will resume at this point for the next call of inflate(). * * - Provide more output starting at next_out and update next_out and avail_out * accordingly. inflate() provides as much output as possible, until there * is no more input data or no more space in the output buffer (see below * about the flush parameter). * * Before the call of inflate(), the application should ensure that at least * one of the actions is possible, by providing more input and/or consuming * more output, and updating the next_* and avail_* values accordingly. * The application can consume the uncompressed output when it wants, for * example when the output buffer is full (avail_out == 0), or after each * call of inflate(). If inflate returns Z_OK and with zero avail_out, it * must be called again after making room in the output buffer because there * might be more output pending. * * The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, * Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much * output as possible to the output buffer. Z_BLOCK requests that inflate() stop * if and when it gets to the next deflate block boundary. When decoding the * zlib or gzip format, this will cause inflate() to return immediately after * the header and before the first block. When doing a raw inflate, inflate() * will go ahead and process the first block, and will return when it gets to * the end of that block, or when it runs out of data. * * The Z_BLOCK option assists in appending to or combining deflate streams. * Also to assist in this, on return inflate() will set strm->data_type to the * number of unused bits in the last byte taken from strm->next_in, plus 64 * if inflate() is currently decoding the last block in the deflate stream, * plus 128 if inflate() returned immediately after decoding an end-of-block * code or decoding the complete header up to just before the first byte of the * deflate stream. The end-of-block will not be indicated until all of the * uncompressed data from that block has been written to strm->next_out. The * number of unused bits may in general be greater than seven, except when * bit 7 of data_type is set, in which case the number of unused bits will be * less than eight. * * inflate() should normally be called until it returns Z_STREAM_END or an * error. However if all decompression is to be performed in a single step * (a single call of inflate), the parameter flush should be set to * Z_FINISH. In this case all pending input is processed and all pending * output is flushed; avail_out must be large enough to hold all the * uncompressed data. (The size of the uncompressed data may have been saved * by the compressor for this purpose.) The next operation on this stream must * be inflateEnd to deallocate the decompression state. The use of Z_FINISH * is never required, but can be used to inform inflate that a faster approach * may be used for the single inflate() call. * * In this implementation, inflate() always flushes as much output as * possible to the output buffer, and always uses the faster approach on the * first call. So the only effect of the flush parameter in this implementation * is on the return value of inflate(), as noted below, or when it returns early * because Z_BLOCK is used. * * If a preset dictionary is needed after this call (see inflateSetDictionary * below), inflate sets strm->adler to the adler32 checksum of the dictionary * chosen by the compressor and returns Z_NEED_DICT; otherwise it sets * strm->adler to the adler32 checksum of all output produced so far (that is, * total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described * below. At the end of the stream, inflate() checks that its computed adler32 * checksum is equal to that saved by the compressor and returns Z_STREAM_END * only if the checksum is correct. * * inflate() will decompress and check either zlib-wrapped or gzip-wrapped * deflate data. The header type is detected automatically. Any information * contained in the gzip header is not retained, so applications that need that * information should instead use raw inflate, see inflateInit2() below, or * inflateBack() and perform their own processing of the gzip header and * trailer. * * inflate() returns Z_OK if some progress has been made (more input processed * or more output produced), Z_STREAM_END if the end of the compressed data has * been reached and all uncompressed output has been produced, Z_NEED_DICT if a * preset dictionary is needed at this point, Z_DATA_ERROR if the input data was * corrupted (input stream not conforming to the zlib format or incorrect check * value), Z_STREAM_ERROR if the stream structure was inconsistent (for example * if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, * Z_BUF_ERROR if no progress is possible or if there was not enough room in the * output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and * inflate() can be called again with more input and more output space to * continue decompressing. If Z_DATA_ERROR is returned, the application may then * call inflateSync() to look for a good compression block if a partial recovery * of the data is desired. */ ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); /* * All dynamically allocated data structures for this stream are freed. * This function discards any unprocessed input and does not flush any * pending output. * * inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state * was inconsistent. In the error case, msg may be set but then points to a * static string (which must not be deallocated). */ /* Advanced functions */ /* * The following functions are needed only in some special applications. */ /* * ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, * int level, * int method, * int windowBits, * int memLevel, * int strategy)); * * This is another version of deflateInit with more compression options. The * fields next_in, zalloc, zfree and opaque must be initialized before by * the caller. * * The method parameter is the compression method. It must be Z_DEFLATED in * this version of the library. * * The windowBits parameter is the base two logarithm of the window size * (the size of the history buffer). It should be in the range 8..15 for this * version of the library. Larger values of this parameter result in better * compression at the expense of memory usage. The default value is 15 if * deflateInit is used instead. * * windowBits can also be -8..-15 for raw deflate. In this case, -windowBits * determines the window size. deflate() will then generate raw deflate data * with no zlib header or trailer, and will not compute an adler32 check value. * * windowBits can also be greater than 15 for optional gzip encoding. Add * 16 to windowBits to write a simple gzip header and trailer around the * compressed data instead of a zlib wrapper. The gzip header will have no * file name, no extra data, no comment, no modification time (set to zero), * no header crc, and the operating system will be set to 255 (unknown). If a * gzip stream is being written, strm->adler is a crc32 instead of an adler32. * * The memLevel parameter specifies how much memory should be allocated * for the internal compression state. memLevel=1 uses minimum memory but * is slow and reduces compression ratio; memLevel=9 uses maximum memory * for optimal speed. The default value is 8. See zconf.h for total memory * usage as a function of windowBits and memLevel. * * The strategy parameter is used to tune the compression algorithm. Use the * value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a * filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no * string match), or Z_RLE to limit match distances to one (run-length * encoding). Filtered data consists mostly of small values with a somewhat * random distribution. In this case, the compression algorithm is tuned to * compress them better. The effect of Z_FILTERED is to force more Huffman * coding and less string matching; it is somewhat intermediate between * Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as * Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy * parameter only affects the compression ratio but not the correctness of the * compressed output even if it is not set appropriately. Z_FIXED prevents the * use of dynamic Huffman codes, allowing for a simpler decoder for special * applications. * * deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough * memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid * method). msg is set to null if there is no error message. deflateInit2 does * not perform any compression: this will be done by deflate(). */ ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, const Bytef *dictionary, uInt dictLength)); /* * Initializes the compression dictionary from the given byte sequence * without producing any compressed output. This function must be called * immediately after deflateInit, deflateInit2 or deflateReset, before any * call of deflate. The compressor and decompressor must use exactly the same * dictionary (see inflateSetDictionary). * * The dictionary should consist of strings (byte sequences) that are likely * to be encountered later in the data to be compressed, with the most commonly * used strings preferably put towards the end of the dictionary. Using a * dictionary is most useful when the data to be compressed is short and can be * predicted with good accuracy; the data can then be compressed better than * with the default empty dictionary. * * Depending on the size of the compression data structures selected by * deflateInit or deflateInit2, a part of the dictionary may in effect be * discarded, for example if the dictionary is larger than the window size in * deflate or deflate2. Thus the strings most likely to be useful should be * put at the end of the dictionary, not at the front. In addition, the * current implementation of deflate will use at most the window size minus * 262 bytes of the provided dictionary. * * Upon return of this function, strm->adler is set to the adler32 value * of the dictionary; the decompressor may later use this value to determine * which dictionary has been used by the compressor. (The adler32 value * applies to the whole dictionary even if only a subset of the dictionary is * actually used by the compressor.) If a raw deflate was requested, then the * adler32 value is not computed and strm->adler is not set. * * deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a * parameter is invalid (such as NULL dictionary) or the stream state is * inconsistent (for example if deflate has already been called for this stream * or if the compression method is bsort). deflateSetDictionary does not * perform any compression: this will be done by deflate(). */ ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, z_streamp source)); /* * Sets the destination stream as a complete copy of the source stream. * * This function can be useful when several compression strategies will be * tried, for example when there are several ways of pre-processing the input * data with a filter. The streams that will be discarded should then be freed * by calling deflateEnd. Note that deflateCopy duplicates the internal * compression state which can be quite large, so this strategy is slow and * can consume lots of memory. * * deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not * enough memory, Z_STREAM_ERROR if the source stream state was inconsistent * (such as zalloc being NULL). msg is left unchanged in both source and * destination. */ #if XNU_KERNEL_PRIVATE typedef int (*z_input_func) (z_streamp strm, Bytef *buf, unsigned size); typedef int (*z_output_func)(z_streamp strm, Bytef *buf, unsigned size); ZEXTERN int ZEXPORT deflateResetWithIO(z_streamp strm, z_input_func zinput, z_output_func zoutput); #endif /* XNU_KERNEL_PRIVATE */ ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); /* * This function is equivalent to deflateEnd followed by deflateInit, * but does not free and reallocate all the internal compression state. * The stream will keep the same compression level and any other attributes * that may have been set by deflateInit2. * * deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent (such as zalloc or state being NULL). */ ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, int level, int strategy)); /* * Dynamically update the compression level and compression strategy. The * interpretation of level and strategy is as in deflateInit2. This can be * used to switch between compression and straight copy of the input data, or * to switch to a different kind of input data requiring a different * strategy. If the compression level is changed, the input available so far * is compressed with the old level (and may be flushed); the new level will * take effect only at the next call of deflate(). * * Before the call of deflateParams, the stream state must be set as for * a call of deflate(), since the currently available input may have to * be compressed and flushed. In particular, strm->avail_out must be non-zero. * * deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source * stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR * if strm->avail_out was zero. */ ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, int good_length, int max_lazy, int nice_length, int max_chain)); /* * Fine tune deflate's internal compression parameters. This should only be * used by someone who understands the algorithm used by zlib's deflate for * searching for the best matching string, and even then only by the most * fanatic optimizer trying to squeeze out the last compressed bit for their * specific input data. Read the deflate.c source code for the meaning of the * max_lazy, good_length, nice_length, and max_chain parameters. * * deflateTune() can be called after deflateInit() or deflateInit2(), and * returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. */ ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, uLong sourceLen)); /* * deflateBound() returns an upper bound on the compressed size after * deflation of sourceLen bytes. It must be called after deflateInit() * or deflateInit2(). This would be used to allocate an output buffer * for deflation in a single pass, and so would be called before deflate(). */ ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, int bits, int value)); /* * deflatePrime() inserts bits in the deflate output stream. The intent * is that this function is used to start off the deflate output with the * bits leftover from a previous deflate stream when appending to it. As such, * this function can only be used for raw deflate, and must be used before the * first deflate() call after a deflateInit2() or deflateReset(). bits must be * less than or equal to 16, and that many of the least significant bits of * value will be inserted in the output. * * deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent. */ ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, gz_headerp head)); /* * deflateSetHeader() provides gzip header information for when a gzip * stream is requested by deflateInit2(). deflateSetHeader() may be called * after deflateInit2() or deflateReset() and before the first call of * deflate(). The text, time, os, extra field, name, and comment information * in the provided gz_header structure are written to the gzip header (xflag is * ignored -- the extra flags are set according to the compression level). The * caller must assure that, if not Z_NULL, name and comment are terminated with * a zero byte, and that if extra is not Z_NULL, that extra_len bytes are * available there. If hcrc is true, a gzip header crc is included. Note that * the current versions of the command-line version of gzip (up through version * 1.3.x) do not support header crc's, and will report that it is a "multi-part * gzip file" and give up. * * If deflateSetHeader is not used, the default gzip header has text false, * the time set to zero, and os set to 255, with no extra, name, or comment * fields. The gzip header is returned to the default state by deflateReset(). * * deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent. */ /* * ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, * int windowBits)); * * This is another version of inflateInit with an extra parameter. The * fields next_in, avail_in, zalloc, zfree and opaque must be initialized * before by the caller. * * The windowBits parameter is the base two logarithm of the maximum window * size (the size of the history buffer). It should be in the range 8..15 for * this version of the library. The default value is 15 if inflateInit is used * instead. windowBits must be greater than or equal to the windowBits value * provided to deflateInit2() while compressing, or it must be equal to 15 if * deflateInit2() was not used. If a compressed stream with a larger window * size is given as input, inflate() will return with the error code * Z_DATA_ERROR instead of trying to allocate a larger window. * * windowBits can also be -8..-15 for raw inflate. In this case, -windowBits * determines the window size. inflate() will then process raw deflate data, * not looking for a zlib or gzip header, not generating a check value, and not * looking for any check values for comparison at the end of the stream. This * is for use with other formats that use the deflate compressed data format * such as zip. Those formats provide their own check values. If a custom * format is developed using the raw deflate format for compressed data, it is * recommended that a check value such as an adler32 or a crc32 be applied to * the uncompressed data as is done in the zlib, gzip, and zip formats. For * most applications, the zlib format should be used as is. Note that comments * above on the use in deflateInit2() applies to the magnitude of windowBits. * * windowBits can also be greater than 15 for optional gzip decoding. Add * 32 to windowBits to enable zlib and gzip decoding with automatic header * detection, or add 16 to decode only the gzip format (the zlib format will * return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is * a crc32 instead of an adler32. * * inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough * memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg * is set to null if there is no error message. inflateInit2 does not perform * any decompression apart from reading the zlib header if present: this will * be done by inflate(). (So next_in and avail_in may be modified, but next_out * and avail_out are unchanged.) */ ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, const Bytef *dictionary, uInt dictLength)); /* * Initializes the decompression dictionary from the given uncompressed byte * sequence. This function must be called immediately after a call of inflate, * if that call returned Z_NEED_DICT. The dictionary chosen by the compressor * can be determined from the adler32 value returned by that call of inflate. * The compressor and decompressor must use exactly the same dictionary (see * deflateSetDictionary). For raw inflate, this function can be called * immediately after inflateInit2() or inflateReset() and before any call of * inflate() to set the dictionary. The application must insure that the * dictionary that was used for compression is provided. * * inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a * parameter is invalid (such as NULL dictionary) or the stream state is * inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the * expected one (incorrect adler32 value). inflateSetDictionary does not * perform any decompression: this will be done by subsequent calls of * inflate(). */ ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); /* * Skips invalid compressed data until a full flush point (see above the * description of deflate with Z_FULL_FLUSH) can be found, or until all * available input is skipped. No output is provided. * * inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR * if no more input was provided, Z_DATA_ERROR if no flush point has been found, * or Z_STREAM_ERROR if the stream structure was inconsistent. In the success * case, the application may save the current current value of total_in which * indicates where valid compressed data was found. In the error case, the * application may repeatedly call inflateSync, providing more input each time, * until success or end of the input data. */ ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, z_streamp source)); /* * Sets the destination stream as a complete copy of the source stream. * * This function can be useful when randomly accessing a large stream. The * first pass through the stream can periodically record the inflate state, * allowing restarting inflate at those points when randomly accessing the * stream. * * inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not * enough memory, Z_STREAM_ERROR if the source stream state was inconsistent * (such as zalloc being NULL). msg is left unchanged in both source and * destination. */ ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); /* * This function is equivalent to inflateEnd followed by inflateInit, * but does not free and reallocate all the internal decompression state. * The stream will keep attributes that may have been set by inflateInit2. * * inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent (such as zalloc or state being NULL). */ ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, int bits, int value)); /* * This function inserts bits in the inflate input stream. The intent is * that this function is used to start inflating at a bit position in the * middle of a byte. The provided bits will be used before any bytes are used * from next_in. This function should only be used with raw inflate, and * should be used before the first inflate() call after inflateInit2() or * inflateReset(). bits must be less than or equal to 16, and that many of the * least significant bits of value will be inserted in the input. * * inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent. */ ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, gz_headerp head)); /* * inflateGetHeader() requests that gzip header information be stored in the * provided gz_header structure. inflateGetHeader() may be called after * inflateInit2() or inflateReset(), and before the first call of inflate(). * As inflate() processes the gzip stream, head->done is zero until the header * is completed, at which time head->done is set to one. If a zlib stream is * being decoded, then head->done is set to -1 to indicate that there will be * no gzip header information forthcoming. Note that Z_BLOCK can be used to * force inflate() to return immediately after header processing is complete * and before any actual data is decompressed. * * The text, time, xflags, and os fields are filled in with the gzip header * contents. hcrc is set to true if there is a header CRC. (The header CRC * was valid if done is set to one.) If extra is not Z_NULL, then extra_max * contains the maximum number of bytes to write to extra. Once done is true, * extra_len contains the actual extra field length, and extra contains the * extra field, or that field truncated if extra_max is less than extra_len. * If name is not Z_NULL, then up to name_max characters are written there, * terminated with a zero unless the length is greater than name_max. If * comment is not Z_NULL, then up to comm_max characters are written there, * terminated with a zero unless the length is greater than comm_max. When * any of extra, name, or comment are not Z_NULL and the respective field is * not present in the header, then that field is set to Z_NULL to signal its * absence. This allows the use of deflateSetHeader() with the returned * structure to duplicate the header. However if those fields are set to * allocated memory, then the application will need to save those pointers * elsewhere so that they can be eventually freed. * * If inflateGetHeader is not used, then the header information is simply * discarded. The header is always checked for validity, including the header * CRC if present. inflateReset() will reset the process to discard the header * information. The application would need to call inflateGetHeader() again to * retrieve the header from the next gzip stream. * * inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source * stream state was inconsistent. */ /* * ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, * unsigned char FAR *window)); * * Initialize the internal stream state for decompression using inflateBack() * calls. The fields zalloc, zfree and opaque in strm must be initialized * before the call. If zalloc and zfree are Z_NULL, then the default library- * derived memory allocation routines are used. windowBits is the base two * logarithm of the window size, in the range 8..15. window is a caller * supplied buffer of that size. Except for special applications where it is * assured that deflate was used with small window sizes, windowBits must be 15 * and a 32K byte window must be supplied to be able to decompress general * deflate streams. * * See inflateBack() for the usage of these routines. * * inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of * the paramaters are invalid, Z_MEM_ERROR if the internal state could not * be allocated, or Z_VERSION_ERROR if the version of the library does not * match the version of the header file. */ typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, in_func in, void FAR *in_desc, out_func out, void FAR *out_desc)); /* * inflateBack() does a raw inflate with a single call using a call-back * interface for input and output. This is more efficient than inflate() for * file i/o applications in that it avoids copying between the output and the * sliding window by simply making the window itself the output buffer. This * function trusts the application to not change the output buffer passed by * the output function, at least until inflateBack() returns. * * inflateBackInit() must be called first to allocate the internal state * and to initialize the state with the user-provided window buffer. * inflateBack() may then be used multiple times to inflate a complete, raw * deflate stream with each call. inflateBackEnd() is then called to free * the allocated state. * * A raw deflate stream is one with no zlib or gzip header or trailer. * This routine would normally be used in a utility that reads zip or gzip * files and writes out uncompressed files. The utility would decode the * header and process the trailer on its own, hence this routine expects * only the raw deflate stream to decompress. This is different from the * normal behavior of inflate(), which expects either a zlib or gzip header and * trailer around the deflate stream. * * inflateBack() uses two subroutines supplied by the caller that are then * called by inflateBack() for input and output. inflateBack() calls those * routines until it reads a complete deflate stream and writes out all of the * uncompressed data, or until it encounters an error. The function's * parameters and return types are defined above in the in_func and out_func * typedefs. inflateBack() will call in(in_desc, &buf) which should return the * number of bytes of provided input, and a pointer to that input in buf. If * there is no input available, in() must return zero--buf is ignored in that * case--and inflateBack() will return a buffer error. inflateBack() will call * out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() * should return zero on success, or non-zero on failure. If out() returns * non-zero, inflateBack() will return with an error. Neither in() nor out() * are permitted to change the contents of the window provided to * inflateBackInit(), which is also the buffer that out() uses to write from. * The length written by out() will be at most the window size. Any non-zero * amount of input may be provided by in(). * * For convenience, inflateBack() can be provided input on the first call by * setting strm->next_in and strm->avail_in. If that input is exhausted, then * in() will be called. Therefore strm->next_in must be initialized before * calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called * immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in * must also be initialized, and then if strm->avail_in is not zero, input will * initially be taken from strm->next_in[0 .. strm->avail_in - 1]. * * The in_desc and out_desc parameters of inflateBack() is passed as the * first parameter of in() and out() respectively when they are called. These * descriptors can be optionally used to pass any information that the caller- * supplied in() and out() functions need to do their job. * * On return, inflateBack() will set strm->next_in and strm->avail_in to * pass back any unused input that was provided by the last in() call. The * return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR * if in() or out() returned an error, Z_DATA_ERROR if there was a format * error in the deflate stream (in which case strm->msg is set to indicate the * nature of the error), or Z_STREAM_ERROR if the stream was not properly * initialized. In the case of Z_BUF_ERROR, an input or output error can be * distinguished using strm->next_in which will be Z_NULL only if in() returned * an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to * out() returning non-zero. (in() will always be called before out(), so * strm->next_in is assured to be defined if out() returns non-zero.) Note * that inflateBack() cannot return Z_OK. */ ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); /* * All memory allocated by inflateBackInit() is freed. * * inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream * state was inconsistent. */ ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); /* Return flags indicating compile-time options. * * Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: * 1.0: size of uInt * 3.2: size of uLong * 5.4: size of voidpf (pointer) * 7.6: size of z_off_t * * Compiler, assembler, and debug options: * 8: DEBUG * 9: ASMV or ASMINF -- use ASM code * 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention * 11: 0 (reserved) * * One-time table building (smaller code, but not thread-safe if true): * 12: BUILDFIXED -- build static block decoding tables when needed * 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed * 14,15: 0 (reserved) * * Library content (indicates missing functionality): * 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking * deflate code when not needed) * 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect * and decode gzip streams (to avoid linking crc code) * 18-19: 0 (reserved) * * Operation variations (changes in library functionality): * 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate * 21: FASTEST -- deflate algorithm with only one, lowest compression level * 22,23: 0 (reserved) * * The sprintf variant used by gzprintf (zero is best): * 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format * 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! * 26: 0 = returns value, 1 = void -- 1 means inferred string length returned * * Remainder: * 27-31: 0 (reserved) */ /* utility functions */ /* * The following utility functions are implemented on top of the * basic stream-oriented functions. To simplify the interface, some * default options are assumed (compression level and memory usage, * standard memory allocation functions). The source code of these * utility functions can easily be modified if you need special options. */ ZEXTERN int ZEXPORT compress OF((Bytef * dest, uLongf *destLen, const Bytef *source, uLong sourceLen)); /* * Compresses the source buffer into the destination buffer. sourceLen is * the byte length of the source buffer. Upon entry, destLen is the total * size of the destination buffer, which must be at least the value returned * by compressBound(sourceLen). Upon exit, destLen is the actual size of the * compressed buffer. * This function can be used to compress a whole file at once if the * input file is mmap'ed. * compress returns Z_OK if success, Z_MEM_ERROR if there was not * enough memory, Z_BUF_ERROR if there was not enough room in the output * buffer. */ ZEXTERN int ZEXPORT compress2 OF((Bytef * dest, uLongf *destLen, const Bytef *source, uLong sourceLen, int level)); /* * Compresses the source buffer into the destination buffer. The level * parameter has the same meaning as in deflateInit. sourceLen is the byte * length of the source buffer. Upon entry, destLen is the total size of the * destination buffer, which must be at least the value returned by * compressBound(sourceLen). Upon exit, destLen is the actual size of the * compressed buffer. * * compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough * memory, Z_BUF_ERROR if there was not enough room in the output buffer, * Z_STREAM_ERROR if the level parameter is invalid. */ ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); /* * compressBound() returns an upper bound on the compressed size after * compress() or compress2() on sourceLen bytes. It would be used before * a compress() or compress2() call to allocate the destination buffer. */ ZEXTERN int ZEXPORT uncompress OF((Bytef * dest, uLongf *destLen, const Bytef *source, uLong sourceLen)); /* * Decompresses the source buffer into the destination buffer. sourceLen is * the byte length of the source buffer. Upon entry, destLen is the total * size of the destination buffer, which must be large enough to hold the * entire uncompressed data. (The size of the uncompressed data must have * been saved previously by the compressor and transmitted to the decompressor * by some mechanism outside the scope of this compression library.) * Upon exit, destLen is the actual size of the compressed buffer. * This function can be used to decompress a whole file at once if the * input file is mmap'ed. * * uncompress returns Z_OK if success, Z_MEM_ERROR if there was not * enough memory, Z_BUF_ERROR if there was not enough room in the output * buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. */ #if XNU_KERNEL_PRIVATE ZEXTERN uLong zlib_deflate_memory_size(int wbits, int memlevel); #endif /* XNU_KERNEL_PRIVATE */ #if !KERNEL typedef voidp gzFile; ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); /* * Opens a gzip (.gz) file for reading or writing. The mode parameter * is as in fopen ("rb" or "wb") but can also include a compression level * ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for * Huffman only compression as in "wb1h", or 'R' for run-length encoding * as in "wb1R". (See the description of deflateInit2 for more information * about the strategy parameter.) * * gzopen can be used to read a file which is not in gzip format; in this * case gzread will directly read from the file without decompression. * * gzopen returns NULL if the file could not be opened or if there was * insufficient memory to allocate the (de)compression state; errno * can be checked to distinguish the two cases (if errno is zero, the * zlib error is Z_MEM_ERROR). */ ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); /* * gzdopen() associates a gzFile with the file descriptor fd. File * descriptors are obtained from calls like open, dup, creat, pipe or * fileno (in the file has been previously opened with fopen). * The mode parameter is as in gzopen. * The next call of gzclose on the returned gzFile will also close the * file descriptor fd, just like fclose(fdopen(fd), mode) closes the file * descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). * gzdopen returns NULL if there was insufficient memory to allocate * the (de)compression state. */ ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); /* * Dynamically update the compression level or strategy. See the description * of deflateInit2 for the meaning of these parameters. * gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not * opened for writing. */ ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); /* * Reads the given number of uncompressed bytes from the compressed file. * If the input file was not in gzip format, gzread copies the given number * of bytes into the buffer. * gzread returns the number of uncompressed bytes actually read (0 for * end of file, -1 for error). */ ZEXTERN int ZEXPORT gzwrite OF((gzFile file, voidpc buf, unsigned len)); /* * Writes the given number of uncompressed bytes into the compressed file. * gzwrite returns the number of uncompressed bytes actually written * (0 in case of error). */ ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); /* * Converts, formats, and writes the args to the compressed file under * control of the format string, as in fprintf. gzprintf returns the number of * uncompressed bytes actually written (0 in case of error). The number of * uncompressed bytes written is limited to 4095. The caller should assure that * this limit is not exceeded. If it is exceeded, then gzprintf() will return * return an error (0) with nothing written. In this case, there may also be a * buffer overflow with unpredictable consequences, which is possible only if * zlib was compiled with the insecure functions sprintf() or vsprintf() * because the secure snprintf() or vsnprintf() functions were not available. */ ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); /* * Writes the given null-terminated string to the compressed file, excluding * the terminating null character. * gzputs returns the number of characters written, or -1 in case of error. */ ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); /* * Reads bytes from the compressed file until len-1 characters are read, or * a newline character is read and transferred to buf, or an end-of-file * condition is encountered. The string is then terminated with a null * character. * gzgets returns buf, or Z_NULL in case of error. */ ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); /* * Writes c, converted to an unsigned char, into the compressed file. * gzputc returns the value that was written, or -1 in case of error. */ ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); /* * Reads one byte from the compressed file. gzgetc returns this byte * or -1 in case of end of file or error. */ ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); /* * Push one character back onto the stream to be read again later. * Only one character of push-back is allowed. gzungetc() returns the * character pushed, or -1 on failure. gzungetc() will fail if a * character has been pushed but not read yet, or if c is -1. The pushed * character will be discarded if the stream is repositioned with gzseek() * or gzrewind(). */ ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); /* * Flushes all pending output into the compressed file. The parameter * flush is as in the deflate() function. The return value is the zlib * error number (see function gzerror below). gzflush returns Z_OK if * the flush parameter is Z_FINISH and all output could be flushed. * gzflush should be called only when strictly necessary because it can * degrade compression. */ ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, z_off_t offset, int whence)); /* * Sets the starting position for the next gzread or gzwrite on the * given compressed file. The offset represents a number of bytes in the * uncompressed data stream. The whence parameter is defined as in lseek(2); * the value SEEK_END is not supported. * If the file is opened for reading, this function is emulated but can be * extremely slow. If the file is opened for writing, only forward seeks are * supported; gzseek then compresses a sequence of zeroes up to the new * starting position. * * gzseek returns the resulting offset location as measured in bytes from * the beginning of the uncompressed stream, or -1 in case of error, in * particular if the file is opened for writing and the new starting position * would be before the current position. */ ZEXTERN int ZEXPORT gzrewind OF((gzFile file)); /* * Rewinds the given file. This function is supported only for reading. * * gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) */ ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); /* * Returns the starting position for the next gzread or gzwrite on the * given compressed file. This position represents a number of bytes in the * uncompressed data stream. * * gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) */ ZEXTERN int ZEXPORT gzeof OF((gzFile file)); /* * Returns 1 when EOF has previously been detected reading the given * input stream, otherwise zero. */ ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); /* * Returns 1 if file is being read directly without decompression, otherwise * zero. */ ZEXTERN int ZEXPORT gzclose OF((gzFile file)); /* * Flushes all pending output if necessary, closes the compressed file * and deallocates all the (de)compression state. The return value is the zlib * error number (see function gzerror below). */ ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); /* * Returns the error message for the last error which occurred on the * given compressed file. errnum is set to zlib error number. If an * error occurred in the file system and not in the compression library, * errnum is set to Z_ERRNO and the application may consult errno * to get the exact error code. */ ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); /* * Clears the error and end-of-file flags for file. This is analogous to the * clearerr() function in stdio. This is useful for continuing to read a gzip * file that is being written concurrently. */ #endif /* KERNEL */ /* checksum functions */ /* * These functions are not related to compression but are exported * anyway because they might be useful in applications using the * compression library. */ ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); /* * Update a running Adler-32 checksum with the bytes buf[0..len-1] and * return the updated checksum. If buf is NULL, this function returns * the required initial value for the checksum. * An Adler-32 checksum is almost as reliable as a CRC32 but can be computed * much faster. Usage example: * * uLong adler = adler32(0L, Z_NULL, 0); * * while (read_buffer(buffer, length) != EOF) { * adler = adler32(adler, buffer, length); * } * if (adler != original_adler) error(); */ ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, z_off_t len2)); /* * Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 * and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for * each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of * seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. */ ZEXTERN uLong ZEXPORT z_crc32 OF((uLong crc, const Bytef *buf, uInt len)); /* * Update a running CRC-32 with the bytes buf[0..len-1] and return the * updated CRC-32. If buf is NULL, this function returns the required initial * value for the for the crc. Pre- and post-conditioning (one's complement) is * performed within this function so it shouldn't be done by the application. * Usage example: * * uLong crc = crc32(0L, Z_NULL, 0); * * while (read_buffer(buffer, length) != EOF) { * crc = crc32(crc, buffer, length); * } * if (crc != original_crc) error(); */ ZEXTERN uLong ZEXPORT z_crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); /* * Combine two CRC-32 check values into one. For two sequences of bytes, * seq1 and seq2 with lengths len1 and len2, CRC-32 check values were * calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 * check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and * len2. */ /* various hacks, don't look :) */ /* deflateInit and inflateInit are macros to allow checking the zlib version * and the compiler's view of z_stream: */ ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, const char *version, int stream_size)); ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, const char *version, int stream_size)); ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, int windowBits, int memLevel, int strategy, const char *version, int stream_size)); ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, const char *version, int stream_size)); ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, unsigned char FAR *window, const char *version, int stream_size)); #define deflateInit(strm, level) \ deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) #define inflateInit(strm) \ inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ (strategy), ZLIB_VERSION, sizeof(z_stream)) #define inflateInit2(strm, windowBits) \ inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) #define inflateBackInit(strm, windowBits, window) \ inflateBackInit_((strm), (windowBits), (window), \ ZLIB_VERSION, sizeof(z_stream)) #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) struct internal_state {int dummy;}; /* hack for buggy compilers */ #endif ZEXTERN const char * ZEXPORT zError OF((int)); ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z)); ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); #ifdef __cplusplus } #endif #endif /* ZLIB_H */