diff options
Diffstat (limited to 'zlib-1.2.5/zlib.h')
| -rw-r--r-- | zlib-1.2.5/zlib.h | 1613 |
1 files changed, 0 insertions, 1613 deletions
diff --git a/zlib-1.2.5/zlib.h b/zlib-1.2.5/zlib.h deleted file mode 100644 index bfbba83e8..000000000 --- a/zlib-1.2.5/zlib.h +++ /dev/null @@ -1,1613 +0,0 @@ -/* zlib.h -- interface of the 'zlib' general purpose compression library - version 1.2.5, April 19th, 2010 - - Copyright (C) 1995-2010 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 - -#include "zconf.h" - -#ifdef __cplusplus -extern "C" { -#endif - -#define ZLIB_VERSION "1.2.5" -#define ZLIB_VERNUM 0x1250 -#define ZLIB_VER_MAJOR 1 -#define ZLIB_VER_MINOR 2 -#define ZLIB_VER_REVISION 5 -#define ZLIB_VER_SUBREVISION 0 - -/* - 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, - 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 -#define Z_SYNC_FLUSH 2 -#define Z_FULL_FLUSH 3 -#define Z_FINISH 4 -#define Z_BLOCK 5 -#define Z_TREES 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, or - 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 accumulate 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. This - completes the current deflate block and follows it with an empty stored block - that is three bits plus filler bits to the next byte, followed by four bytes - (00 00 ff ff). - - If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the - output buffer, but the output is not aligned to a byte boundary. All of the - input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. - This completes the current deflate block and follows it with an empty fixed - codes block that is 10 bits long. This assures that enough bytes are output - in order for the decompressor to finish the block before the empty fixed code - block. - - If flush is set to Z_BLOCK, a deflate block is completed and emitted, as - for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to - seven bits of the current block are held to be written as the next byte after - the next deflate block is completed. In this case, the decompressor may not - be provided enough bits at this point in order to complete decompression of - the data provided so far to the compressor. It may need to wait for the next - block to be emitted. This is for advanced applications that need to control - the emission of deflate blocks. - - 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 Z_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, or Z_STREAM_ERROR if the parameters are - invalid, such as a null pointer to the structure. msg is set to null if - there is no error message. inflateInit does not perform any decompression - apart from possibly reading the zlib header if present: actual decompression - will be done by inflate(). (So next_in and avail_in may be modified, but - next_out and avail_out are unused and unchanged.) The current implementation - of inflateInit() does not process any header information -- that is deferred - until inflate() is called. -*/ - - -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, - Z_BLOCK, or Z_TREES. 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. data_type is set as noted here every time inflate() returns for all - flush options, and so can be used to determine the amount of currently - consumed input in bits. - - The Z_TREES option behaves as Z_BLOCK does, but it also returns when the - end of each deflate block header is reached, before any actual data in that - block is decoded. This allows the caller to determine the length of the - deflate block header for later use in random access within a deflate block. - 256 is added to the value of strm->data_type when inflate() returns - immediately after reaching the end of the deflate block header. - - 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 or Z_TREES 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() can decompress and check either zlib-wrapped or gzip-wrapped - deflate data. The header type is detected automatically, if requested when - initializing with inflateInit2(). 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 - next_in or next_out was Z_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_STRATEGY 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 any parameter is invalid (such as an invalid - method), or 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. 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 - provided in deflateInit or deflateInit2. 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 (e.g. dictionary being Z_NULL) 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 Z_NULL). msg is left unchanged in both source and - destination. -*/ - -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 Z_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(), and after deflateSetHeader(), if used. 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 zero to request that inflate use the window size in - the zlib header of the compressed stream. - - 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_VERSION_ERROR if the zlib library version is incompatible with the - version assumed by the caller, or Z_STREAM_ERROR if the parameters are - invalid, such as a null pointer to the structure. msg is set to null if - there is no error message. inflateInit2 does not perform any decompression - apart from possibly reading the zlib header if present: actual decompression - will be done by inflate(). (So next_in and avail_in may be modified, but - next_out and avail_out are unused and unchanged.) The current implementation - of inflateInit2() does not process any header information -- that is - deferred until inflate() is called. -*/ - -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 (e.g. dictionary being Z_NULL) 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 Z_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 Z_NULL). -*/ - -ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, - int windowBits)); -/* - This function is the same as inflateReset, but it also permits changing - the wrap and window size requests. The windowBits parameter is interpreted - the same as it is for inflateInit2. - - inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source - stream state was inconsistent (such as zalloc or state being Z_NULL), or if - the windowBits parameter is invalid. -*/ - -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. - - If bits is negative, then the input stream bit buffer is emptied. Then - inflatePrime() can be called again to put bits in the buffer. This is used - to clear out bits leftover after feeding inflate a block description prior - to feeding inflate codes. - - inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source - stream state was inconsistent. -*/ - -ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); -/* - This function returns two values, one in the lower 16 bits of the return - value, and the other in the remaining upper bits, obtained by shifting the - return value down 16 bits. If the upper value is -1 and the lower value is - zero, then inflate() is currently decoding information outside of a block. - If the upper value is -1 and the lower value is non-zero, then inflate is in - the middle of a stored block, with the lower value equaling the number of - bytes from the input remaining to copy. If the upper value is not -1, then - it is the number of bits back from the current bit position in the input of - the code (literal or length/distance pair) currently being processed. In - that case the lower value is the number of bytes already emitted for that - code. - - A code is being processed if inflate is waiting for more input to complete - decoding of the code, or if it has completed decoding but is waiting for - more output space to write the literal or match data. - - inflateMark() is used to mark locations in the input data for random - access, which may be at bit positions, and to note those cases where the - output of a code may span boundaries of random access blocks. The current - location in the input stream can be determined from avail_in and data_type - as noted in the description for the Z_BLOCK flush parameter for inflate. - - inflateMark returns the value noted above or -1 << 16 if the provided - 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 or Z_TREES 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_in 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 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. - - 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 uncompressed buffer. - - 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. -*/ - - - /* gzip file access functions */ - -/* - This library 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. -*/ - -typedef voidp gzFile; /* opaque gzip file descriptor */ - -/* -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", 'R' for run-length encoding as in "wb1R", or 'F' - for fixed code compression as in "wb9F". (See the description of - deflateInit2 for more information about the strategy parameter.) Also "a" - can be used instead of "w" to request that the gzip stream that will be - written be appended to the file. "+" will result in an error, since reading - and writing to the same gzip file is not supported. - - 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, if there was - insufficient memory to allocate the gzFile state, or if an invalid mode was - specified (an 'r', 'w', or 'a' was not provided, or '+' was provided). - errno can be checked to determine if the reason gzopen failed was that the - file could not be opened. -*/ - -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 (if 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 fd = dup(fd_keep); gz = gzdopen(fd, - mode);. The duplicated descriptor should be saved to avoid a leak, since - gzdopen does not close fd if it fails. - - gzdopen returns NULL if there was insufficient memory to allocate the - gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not - provided, or '+' was provided), or if fd is -1. The file descriptor is not - used until the next gz* read, write, seek, or close operation, so gzdopen - will not detect if fd is invalid (unless fd is -1). -*/ - -ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); -/* - Set the internal buffer size used by this library's functions. The - default buffer size is 8192 bytes. This function must be called after - gzopen() or gzdopen(), and before any other calls that read or write the - file. The buffer memory allocation is always deferred to the first read or - write. Two buffers are allocated, either both of the specified size when - writing, or one of the specified size and the other twice that size when - reading. A larger buffer size of, for example, 64K or 128K bytes will - noticeably increase the speed of decompression (reading). - - The new buffer size also affects the maximum length for gzprintf(). - - gzbuffer() returns 0 on success, or -1 on failure, such as being called - too late. -*/ - -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. - - After reaching the end of a gzip stream in the input, gzread will continue - to read, looking for another gzip stream, or failing that, reading the rest - of the input file directly without decompression. The entire input file - will be read if gzread is called until it returns less than the requested - len. - - gzread returns the number of uncompressed bytes actually read, less than - len for end of file, or -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 written or 0 in case of - error. -*/ - -ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); -/* - Converts, formats, and writes the arguments to the compressed file under - control of the format string, as in fprintf. gzprintf returns the number of - uncompressed bytes actually written, or 0 in case of error. The number of - uncompressed bytes written is limited to 8191, or one less than the buffer - size given to gzbuffer(). The caller should assure that this limit is not - exceeded. If it is exceeded, then gzprintf() will 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. This can be determined using - zlibCompileFlags(). -*/ - -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. If any characters are read or if len == 1, the - string is terminated with a null character. If no characters are read due - to an end-of-file or len < 1, then the buffer is left untouched. - - gzgets returns buf which is a null-terminated string, or it returns NULL - for end-of-file or in case of error. If there was an error, the contents at - buf are indeterminate. -*/ - -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 as the first character - on the next read. At least one character of push-back is allowed. - gzungetc() returns the character pushed, or -1 on failure. gzungetc() will - fail if c is -1, and may fail if a character has been pushed but not read - yet. If gzungetc is used immediately after gzopen or gzdopen, at least the - output buffer size of pushed characters is allowed. (See gzbuffer above.) - 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 is only permitted when writing. - - If the flush parameter is Z_FINISH, the remaining data is written and the - gzip stream is completed in the output. If gzwrite() is called again, a new - gzip stream will be started in the output. gzread() is able to read such - concatented gzip streams. - - gzflush should be called only when strictly necessary because it will - degrade compression if called too often. -*/ - -/* -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, and is zero when starting, even if appending or - reading a gzip stream from the middle of a file using gzdopen(). - - gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) -*/ - -/* -ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); - - Returns the current offset in the file being read or written. This offset - includes the count of bytes that precede the gzip stream, for example when - appending or when using gzdopen() for reading. When reading, the offset - does not include as yet unused buffered input. This information can be used - for a progress indicator. On error, gzoffset() returns -1. -*/ - -ZEXTERN int ZEXPORT gzeof OF((gzFile file)); -/* - Returns true (1) if the end-of-file indicator has been set while reading, - false (0) otherwise. Note that the end-of-file indicator is set only if the - read tried to go past the end of the input, but came up short. Therefore, - just like feof(), gzeof() may return false even if there is no more data to - read, in the event that the last read request was for the exact number of - bytes remaining in the input file. This will happen if the input file size - is an exact multiple of the buffer size. - - If gzeof() returns true, then the read functions will return no more data, - unless the end-of-file indicator is reset by gzclearerr() and the input file - has grown since the previous end of file was detected. -*/ - -ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); -/* - Returns true (1) if file is being copied directly while reading, or false - (0) if file is a gzip stream being decompressed. This state can change from - false to true while reading the input file if the end of a gzip stream is - reached, but is followed by data that is not another gzip stream. - - If the input file is empty, gzdirect() will return true, since the input - does not contain a gzip stream. - - If gzdirect() is used immediately after gzopen() or gzdopen() it will - cause buffers to be allocated to allow reading the file to determine if it - is a gzip file. Therefore if gzbuffer() is used, it should be called before - gzdirect(). -*/ - -ZEXTERN int ZEXPORT gzclose OF((gzFile file)); -/* - Flushes all pending output if necessary, closes the compressed file and - deallocates the (de)compression state. Note that once file is closed, you - cannot call gzerror with file, since its structures have been deallocated. - gzclose must not be called more than once on the same file, just as free - must not be called more than once on the same allocation. - - gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a - file operation error, or Z_OK on success. -*/ - -ZEXTERN int ZEXPORT gzclose_r OF((gzFile file)); -ZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); -/* - Same as gzclose(), but gzclose_r() is only for use when reading, and - gzclose_w() is only for use when writing or appending. The advantage to - using these instead of gzclose() is that they avoid linking in zlib - compression or decompression code that is not used when only reading or only - writing respectively. If gzclose() is used, then both compression and - decompression code will be included the application when linking to a static - zlib library. -*/ - -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. - - The application must not modify the returned string. Future calls to - this function may invalidate the previously returned string. If file is - closed, then the string previously returned by gzerror will no longer be - available. - - gzerror() should be used to distinguish errors from end-of-file for those - functions above that do not distinguish those cases in their return values. -*/ - -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. -*/ - - - /* 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 Z_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 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 Z_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 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)) - -/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or - * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if - * both are true, the application gets the *64 functions, and the regular - * functions are changed to 64 bits) -- in case these are set on systems - * without large file support, _LFS64_LARGEFILE must also be true - */ -#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0 - ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); - ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int)); - ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile)); - ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile)); - ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t)); - ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t)); -#endif - -#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0 -# define gzopen gzopen64 -# define gzseek gzseek64 -# define gztell gztell64 -# define gzoffset gzoffset64 -# define adler32_combine adler32_combine64 -# define crc32_combine crc32_combine64 -# ifdef _LARGEFILE64_SOURCE - ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); - ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int)); - ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile)); - ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile)); - ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t)); - ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t)); -# endif -#else - ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); - ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int)); - ZEXTERN z_off_t ZEXPORT gztell OF((gzFile)); - ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile)); - ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); - ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); -#endif - -/* hack for buggy compilers */ -#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) - struct internal_state {int dummy;}; -#endif - -/* undocumented functions */ -ZEXTERN const char * ZEXPORT zError OF((int)); -ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp)); -ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); -ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int)); - -#ifdef __cplusplus -} -#endif - -#endif /* ZLIB_H */ |