diff options
Diffstat (limited to 'lib/zlib/include/zlib.h')
| -rw-r--r-- | lib/zlib/include/zlib.h | 1786 |
1 files changed, 893 insertions, 893 deletions
diff --git a/lib/zlib/include/zlib.h b/lib/zlib/include/zlib.h index fc81811..b2f0ef0 100644 --- a/lib/zlib/include/zlib.h +++ b/lib/zlib/include/zlib.h @@ -1,893 +1,893 @@ -/* zlib.h -- interface of the 'zlib' general purpose compression library
- version 1.1.4, March 11th, 2002
-
- Copyright (C) 1995-2002 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 ftp://ds.internic.net/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 "1.1.4"
-
-/*
- 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 library also supports reading and writing files in gzip (.gz) format
- with an interface similar to that of stdio.
-
- 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: ascii or binary */
- uLong adler; /* adler32 value of the uncompressed data */
- uLong reserved; /* reserved for future use */
-} z_stream;
-
-typedef z_stream FAR *z_streamp;
-
-/*
- 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 */
-#define Z_SYNC_FLUSH 2
-#define Z_FULL_FLUSH 3
-#define Z_FINISH 4
-/* Allowed flush values; see deflate() 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_DEFAULT_STRATEGY 0
-/* compression strategy; see deflateInit2() below for details */
-
-#define Z_BINARY 0
-#define Z_ASCII 1
-#define Z_UNKNOWN 2
-/* Possible values of the data_type field */
-
-#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.
-
- 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
- the 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).
-
- 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
- 0.1% larger than avail_in plus 12 bytes. 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 data_type if it can make a good guess about
- the input data type (Z_ASCII or Z_BINARY). 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).
-*/
-
-
-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 some
- 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.
-
- If the parameter flush is set to Z_SYNC_FLUSH, inflate flushes as much
- output as possible to the output buffer. The flushing behavior of inflate is
- not specified for values of the flush parameter other than Z_SYNC_FLUSH
- and Z_FINISH, but the current implementation actually flushes as much output
- as possible anyway.
-
- 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 routine
- may be used for the single inflate() call.
-
- If a preset dictionary is needed at this point (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() 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
- adler32 checksum), 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. In the Z_DATA_ERROR
- case, the application may then call inflateSync to look for a good
- compression block.
-*/
-
-
-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.
-
- 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), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
- string match). 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. The strategy parameter only affects
- the compression ratio but not the correctness of the compressed output even
- if it is not set appropriately.
-
- 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.
-
- 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.)
-
- 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.
-*/
-
-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 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. 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.
-
- 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 negative
- memLevel). 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 this call returned Z_NEED_DICT. The dictionary chosen by the compressor
- can be determined from the Adler32 value returned by this call of
- inflate. The compressor and decompressor must use exactly the same
- dictionary (see deflateSetDictionary).
-
- 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 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).
-*/
-
-
- /* 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 0.1% larger than
- sourceLen plus 12 bytes. 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 0.1% larger than sourceLen plus
- 12 bytes. 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 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.
-*/
-
-
-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". (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,
- cvoidp 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).
-*/
-
-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 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 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.
-*/
-
- /* 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 crc32 OF((uLong crc, const Bytef *buf, uInt len));
-/*
- Update a running crc with the bytes buf[0..len-1] and return the updated
- crc. If buf is NULL, this function returns the required initial value
- 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();
-*/
-
-
- /* 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));
-#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))
-
-
-#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
- struct internal_state {int dummy;}; /* hack for buggy compilers */
-#endif
-
-ZEXTERN const char * ZEXPORT zError OF((int err));
-ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
-ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _ZLIB_H */
+/* zlib.h -- interface of the 'zlib' general purpose compression library + version 1.1.4, March 11th, 2002 + + Copyright (C) 1995-2002 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 ftp://ds.internic.net/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 "1.1.4" + +/* + 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 library also supports reading and writing files in gzip (.gz) format + with an interface similar to that of stdio. + + 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: ascii or binary */ + uLong adler; /* adler32 value of the uncompressed data */ + uLong reserved; /* reserved for future use */ +} z_stream; + +typedef z_stream FAR *z_streamp; + +/* + 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 */ +#define Z_SYNC_FLUSH 2 +#define Z_FULL_FLUSH 3 +#define Z_FINISH 4 +/* Allowed flush values; see deflate() 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_DEFAULT_STRATEGY 0 +/* compression strategy; see deflateInit2() below for details */ + +#define Z_BINARY 0 +#define Z_ASCII 1 +#define Z_UNKNOWN 2 +/* Possible values of the data_type field */ + +#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. + + 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 + the 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). + + 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 + 0.1% larger than avail_in plus 12 bytes. 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 data_type if it can make a good guess about + the input data type (Z_ASCII or Z_BINARY). 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). +*/ + + +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 some + 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. + + If the parameter flush is set to Z_SYNC_FLUSH, inflate flushes as much + output as possible to the output buffer. The flushing behavior of inflate is + not specified for values of the flush parameter other than Z_SYNC_FLUSH + and Z_FINISH, but the current implementation actually flushes as much output + as possible anyway. + + 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 routine + may be used for the single inflate() call. + + If a preset dictionary is needed at this point (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() 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 + adler32 checksum), 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. In the Z_DATA_ERROR + case, the application may then call inflateSync to look for a good + compression block. +*/ + + +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. + + 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), or Z_HUFFMAN_ONLY to force Huffman encoding only (no + string match). 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. The strategy parameter only affects + the compression ratio but not the correctness of the compressed output even + if it is not set appropriately. + + 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. + + 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.) + + 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. +*/ + +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 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. 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. + + 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 negative + memLevel). 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 this call returned Z_NEED_DICT. The dictionary chosen by the compressor + can be determined from the Adler32 value returned by this call of + inflate. The compressor and decompressor must use exactly the same + dictionary (see deflateSetDictionary). + + 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 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). +*/ + + + /* 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 0.1% larger than + sourceLen plus 12 bytes. 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 0.1% larger than sourceLen plus + 12 bytes. 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 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. +*/ + + +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". (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, + cvoidp 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). +*/ + +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 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 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. +*/ + + /* 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 crc32 OF((uLong crc, const Bytef *buf, uInt len)); +/* + Update a running crc with the bytes buf[0..len-1] and return the updated + crc. If buf is NULL, this function returns the required initial value + 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(); +*/ + + + /* 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)); +#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)) + + +#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL) + struct internal_state {int dummy;}; /* hack for buggy compilers */ +#endif + +ZEXTERN const char * ZEXPORT zError OF((int err)); +ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z)); +ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); + +#ifdef __cplusplus +} +#endif + +#endif /* _ZLIB_H */ |