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- Committer: Bazaar Package Importer
- Author(s): Aaron M. Ucko
- Date: 2005-05-22 13:57:06 UTC
- mfrom: (2.1.1 hoary)
- Revision ID: james.westby@ubuntu.com-20050522135706-mchag24yf42lu7bu
Tags: 1.1.6-5
* Revert previous change, which seems to have been ineffective for some
reason, in favor of commenting out the problematic Makefile rule
altogether. (Closes: #310151.)
* debian/control: Go back to specifying the URL as part of the
description rather than via a non-standard field that doesn't seem to
have caught on. (Closes: #310240.)
reason, in favor of commenting out the problematic Makefile rule
altogether. (Closes: #310151.)
* debian/control: Go back to specifying the URL as part of the
description rather than via a non-standard field that doesn't seem to
have caught on. (Closes: #310240.)
- files added:
- CMake
- jpeg
- png
- watcom
- zlib
- files removed:
- src/fl_set_gray.cxx
- files modified:
- ANNOUNCEMENT
added
removed
zlib/zlib.h
1
/* zlib.h -- interface of the 'zlib' general purpose compression library
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version 1.2.1, November 17th, 2003
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Copyright (C) 1995-2003 Jean-loup Gailly and Mark Adler
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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Jean-loup Gailly Mark Adler
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jloup@gzip.org madler@alumni.caltech.edu
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The data format used by the zlib library is described by RFCs (Request for
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Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
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(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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*/
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#ifndef ZLIB_H
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#define ZLIB_H
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#include "zconf.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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#define ZLIB_VERSION "1.2.1"
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#define ZLIB_VERNUM 0x1210
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/*
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The 'zlib' compression library provides in-memory compression and
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decompression functions, including integrity checks of the uncompressed
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data. This version of the library supports only one compression method
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(deflation) but other algorithms will be added later and will have the same
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stream interface.
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Compression can be done in a single step if the buffers are large
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enough (for example if an input file is mmap'ed), or can be done by
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repeated calls of the compression function. In the latter case, the
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application must provide more input and/or consume the output
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(providing more output space) before each call.
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The compressed data format used by the in-memory functions is the zlib
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format, which is a zlib wrapper documented in RFC 1950, wrapped around a
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deflate stream, which is itself documented in RFC 1951.
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The library also supports reading and writing files in gzip (.gz) format
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with an interface similar to that of stdio using the functions that start
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with "gz". The gzip format is different from the zlib format. gzip is a
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gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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The zlib format was designed to be compact and fast for use in memory
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and on communications channels. The gzip format was designed for single-
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file compression on file systems, has a larger header than zlib to maintain
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directory information, and uses a different, slower check method than zlib.
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This library does not provide any functions to write gzip files in memory.
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However such functions could be easily written using zlib's deflate function,
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the documentation in the gzip RFC, and the examples in gzio.c.
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The library does not install any signal handler. The decoder checks
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the consistency of the compressed data, so the library should never
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crash even in case of corrupted input.
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*/
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typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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typedef void (*free_func) OF((voidpf opaque, voidpf address));
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struct internal_state;
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typedef struct z_stream_s {
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Bytef *next_in; /* next input byte */
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uInt avail_in; /* number of bytes available at next_in */
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uLong total_in; /* total nb of input bytes read so far */
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Bytef *next_out; /* next output byte should be put there */
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uInt avail_out; /* remaining free space at next_out */
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uLong total_out; /* total nb of bytes output so far */
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char *msg; /* last error message, NULL if no error */
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struct internal_state FAR *state; /* not visible by applications */
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alloc_func zalloc; /* used to allocate the internal state */
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free_func zfree; /* used to free the internal state */
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voidpf opaque; /* private data object passed to zalloc and zfree */
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int data_type; /* best guess about the data type: ascii or binary */
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uLong adler; /* adler32 value of the uncompressed data */
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uLong reserved; /* reserved for future use */
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} z_stream;
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typedef z_stream FAR *z_streamp;
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/*
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The application must update next_in and avail_in when avail_in has
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dropped to zero. It must update next_out and avail_out when avail_out
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has dropped to zero. The application must initialize zalloc, zfree and
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opaque before calling the init function. All other fields are set by the
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compression library and must not be updated by the application.
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The opaque value provided by the application will be passed as the first
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parameter for calls of zalloc and zfree. This can be useful for custom
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memory management. The compression library attaches no meaning to the
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opaque value.
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zalloc must return Z_NULL if there is not enough memory for the object.
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If zlib is used in a multi-threaded application, zalloc and zfree must be
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thread safe.
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On 16-bit systems, the functions zalloc and zfree must be able to allocate
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exactly 65536 bytes, but will not be required to allocate more than this
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if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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pointers returned by zalloc for objects of exactly 65536 bytes *must*
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have their offset normalized to zero. The default allocation function
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provided by this library ensures this (see zutil.c). To reduce memory
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requirements and avoid any allocation of 64K objects, at the expense of
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compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
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The fields total_in and total_out can be used for statistics or
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progress reports. After compression, total_in holds the total size of
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the uncompressed data and may be saved for use in the decompressor
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(particularly if the decompressor wants to decompress everything in
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a single step).
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*/
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/* constants */
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#define Z_NO_FLUSH 0
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#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
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#define Z_SYNC_FLUSH 2
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#define Z_FULL_FLUSH 3
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#define Z_FINISH 4
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#define Z_BLOCK 5
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/* Allowed flush values; see deflate() and inflate() below for details */
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#define Z_OK 0
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#define Z_STREAM_END 1
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#define Z_NEED_DICT 2
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#define Z_ERRNO (-1)
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#define Z_STREAM_ERROR (-2)
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#define Z_DATA_ERROR (-3)
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#define Z_MEM_ERROR (-4)
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#define Z_BUF_ERROR (-5)
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#define Z_VERSION_ERROR (-6)
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/* Return codes for the compression/decompression functions. Negative
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* values are errors, positive values are used for special but normal events.
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*/
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#define Z_NO_COMPRESSION 0
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#define Z_BEST_SPEED 1
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#define Z_BEST_COMPRESSION 9
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#define Z_DEFAULT_COMPRESSION (-1)
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/* compression levels */
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#define Z_FILTERED 1
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#define Z_HUFFMAN_ONLY 2
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#define Z_RLE 3
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#define Z_DEFAULT_STRATEGY 0
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/* compression strategy; see deflateInit2() below for details */
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#define Z_BINARY 0
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#define Z_ASCII 1
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#define Z_UNKNOWN 2
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/* Possible values of the data_type field (though see inflate()) */
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#define Z_DEFLATED 8
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/* The deflate compression method (the only one supported in this version) */
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#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
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#define zlib_version zlibVersion()
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/* for compatibility with versions < 1.0.2 */
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/* basic functions */
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ZEXTERN const char * ZEXPORT zlibVersion OF((void));
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/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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If the first character differs, the library code actually used is
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not compatible with the zlib.h header file used by the application.
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This check is automatically made by deflateInit and inflateInit.
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*/
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/*
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ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
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Initializes the internal stream state for compression. The fields
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zalloc, zfree and opaque must be initialized before by the caller.
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If zalloc and zfree are set to Z_NULL, deflateInit updates them to
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use default allocation functions.
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The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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1 gives best speed, 9 gives best compression, 0 gives no compression at
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all (the input data is simply copied a block at a time).
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Z_DEFAULT_COMPRESSION requests a default compromise between speed and
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compression (currently equivalent to level 6).
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deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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enough memory, Z_STREAM_ERROR if level is not a valid compression level,
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Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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with the version assumed by the caller (ZLIB_VERSION).
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msg is set to null if there is no error message. deflateInit does not
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perform any compression: this will be done by deflate().
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*/
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ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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/*
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deflate compresses as much data as possible, and stops when the input
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buffer becomes empty or the output buffer becomes full. It may introduce some
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output latency (reading input without producing any output) except when
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forced to flush.
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The detailed semantics are as follows. deflate performs one or both of the
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following actions:
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- Compress more input starting at next_in and update next_in and avail_in
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accordingly. If not all input can be processed (because there is not
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enough room in the output buffer), next_in and avail_in are updated and
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processing will resume at this point for the next call of deflate().
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- Provide more output starting at next_out and update next_out and avail_out
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accordingly. This action is forced if the parameter flush is non zero.
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Forcing flush frequently degrades the compression ratio, so this parameter
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should be set only when necessary (in interactive applications).
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Some output may be provided even if flush is not set.
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Before the call of deflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming
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more output, and updating avail_in or avail_out accordingly; avail_out
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should never be zero before the call. The application can consume the
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compressed output when it wants, for example when the output buffer is full
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(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
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and with zero avail_out, it must be called again after making room in the
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output buffer because there might be more output pending.
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If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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flushed to the output buffer and the output is aligned on a byte boundary, so
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that the decompressor can get all input data available so far. (In particular
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avail_in is zero after the call if enough output space has been provided
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before the call.) Flushing may degrade compression for some compression
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algorithms and so it should be used only when necessary.
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If flush is set to Z_FULL_FLUSH, all output is flushed as with
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Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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restart from this point if previous compressed data has been damaged or if
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random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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the compression.
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If deflate returns with avail_out == 0, this function must be called again
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with the same value of the flush parameter and more output space (updated
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avail_out), until the flush is complete (deflate returns with non-zero
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avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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avail_out is greater than six to avoid repeated flush markers due to
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avail_out == 0 on return.
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If the parameter flush is set to Z_FINISH, pending input is processed,
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pending output is flushed and deflate returns with Z_STREAM_END if there
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was enough output space; if deflate returns with Z_OK, this function must be
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called again with Z_FINISH and more output space (updated avail_out) but no
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more input data, until it returns with Z_STREAM_END or an error. After
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deflate has returned Z_STREAM_END, the only possible operations on the
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stream are deflateReset or deflateEnd.
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Z_FINISH can be used immediately after deflateInit if all the compression
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is to be done in a single step. In this case, avail_out must be at least
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the value returned by deflateBound (see below). If deflate does not return
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Z_STREAM_END, then it must be called again as described above.
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deflate() sets strm->adler to the adler32 checksum of all input read
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so far (that is, total_in bytes).
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deflate() may update data_type if it can make a good guess about
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the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
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binary. This field is only for information purposes and does not affect
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the compression algorithm in any manner.
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deflate() returns Z_OK if some progress has been made (more input
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processed or more output produced), Z_STREAM_END if all input has been
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consumed and all output has been produced (only when flush is set to
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Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
295
(for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
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fatal, and deflate() can be called again with more input and more output
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space to continue compressing.
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*/
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ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
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/*
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All dynamically allocated data structures for this stream are freed.
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This function discards any unprocessed input and does not flush any
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pending output.
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deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
308
stream state was inconsistent, Z_DATA_ERROR if the stream was freed
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prematurely (some input or output was discarded). In the error case,
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msg may be set but then points to a static string (which must not be
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deallocated).
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*/
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/*
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ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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Initializes the internal stream state for decompression. The fields
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next_in, avail_in, zalloc, zfree and opaque must be initialized before by
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the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
321
value depends on the compression method), inflateInit determines the
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compression method from the zlib header and allocates all data structures
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accordingly; otherwise the allocation will be deferred to the first call of
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inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
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use default allocation functions.
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
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version assumed by the caller. msg is set to null if there is no error
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message. inflateInit does not perform any decompression apart from reading
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the zlib header if present: this will be done by inflate(). (So next_in and
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avail_in may be modified, but next_out and avail_out are unchanged.)
333
*/
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ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
337
/*
338
inflate decompresses as much data as possible, and stops when the input
339
buffer becomes empty or the output buffer becomes full. It may introduce
340
some output latency (reading input without producing any output) except when
341
forced to flush.
342
343
The detailed semantics are as follows. inflate performs one or both of the
344
following actions:
345
346
- Decompress more input starting at next_in and update next_in and avail_in
347
accordingly. If not all input can be processed (because there is not
348
enough room in the output buffer), next_in is updated and processing
349
will resume at this point for the next call of inflate().
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- Provide more output starting at next_out and update next_out and avail_out
352
accordingly. inflate() provides as much output as possible, until there
353
is no more input data or no more space in the output buffer (see below
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about the flush parameter).
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Before the call of inflate(), the application should ensure that at least
357
one of the actions is possible, by providing more input and/or consuming
358
more output, and updating the next_* and avail_* values accordingly.
359
The application can consume the uncompressed output when it wants, for
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example when the output buffer is full (avail_out == 0), or after each
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call of inflate(). If inflate returns Z_OK and with zero avail_out, it
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must be called again after making room in the output buffer because there
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might be more output pending.
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The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
366
Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
367
output as possible to the output buffer. Z_BLOCK requests that inflate() stop
368
if and when it get to the next deflate block boundary. When decoding the zlib
369
or gzip format, this will cause inflate() to return immediately after the
370
header and before the first block. When doing a raw inflate, inflate() will
371
go ahead and process the first block, and will return when it gets to the end
372
of that block, or when it runs out of data.
373
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The Z_BLOCK option assists in appending to or combining deflate streams.
375
Also to assist in this, on return inflate() will set strm->data_type to the
376
number of unused bits in the last byte taken from strm->next_in, plus 64
377
if inflate() is currently decoding the last block in the deflate stream,
378
plus 128 if inflate() returned immediately after decoding an end-of-block
379
code or decoding the complete header up to just before the first byte of the
380
deflate stream. The end-of-block will not be indicated until all of the
381
uncompressed data from that block has been written to strm->next_out. The
382
number of unused bits may in general be greater than seven, except when
383
bit 7 of data_type is set, in which case the number of unused bits will be
384
less than eight.
385
386
inflate() should normally be called until it returns Z_STREAM_END or an
387
error. However if all decompression is to be performed in a single step
388
(a single call of inflate), the parameter flush should be set to
389
Z_FINISH. In this case all pending input is processed and all pending
390
output is flushed; avail_out must be large enough to hold all the
391
uncompressed data. (The size of the uncompressed data may have been saved
392
by the compressor for this purpose.) The next operation on this stream must
393
be inflateEnd to deallocate the decompression state. The use of Z_FINISH
394
is never required, but can be used to inform inflate that a faster approach
395
may be used for the single inflate() call.
396
397
In this implementation, inflate() always flushes as much output as
398
possible to the output buffer, and always uses the faster approach on the
399
first call. So the only effect of the flush parameter in this implementation
400
is on the return value of inflate(), as noted below, or when it returns early
401
because Z_BLOCK is used.
402
403
If a preset dictionary is needed after this call (see inflateSetDictionary
404
below), inflate sets strm-adler to the adler32 checksum of the dictionary
405
chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
406
strm->adler to the adler32 checksum of all output produced so far (that is,
407
total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
408
below. At the end of the stream, inflate() checks that its computed adler32
409
checksum is equal to that saved by the compressor and returns Z_STREAM_END
410
only if the checksum is correct.
411
412
inflate() will decompress and check either zlib-wrapped or gzip-wrapped
413
deflate data. The header type is detected automatically. Any information
414
contained in the gzip header is not retained, so applications that need that
415
information should instead use raw inflate, see inflateInit2() below, or
416
inflateBack() and perform their own processing of the gzip header and
417
trailer.
418
419
inflate() returns Z_OK if some progress has been made (more input processed
420
or more output produced), Z_STREAM_END if the end of the compressed data has
421
been reached and all uncompressed output has been produced, Z_NEED_DICT if a
422
preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
423
corrupted (input stream not conforming to the zlib format or incorrect check
424
value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
425
if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
426
Z_BUF_ERROR if no progress is possible or if there was not enough room in the
427
output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
428
inflate() can be called again with more input and more output space to
429
continue decompressing. If Z_DATA_ERROR is returned, the application may then
430
call inflateSync() to look for a good compression block if a partial recovery
431
of the data is desired.
432
*/
433
434
435
ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
436
/*
437
All dynamically allocated data structures for this stream are freed.
438
This function discards any unprocessed input and does not flush any
439
pending output.
440
441
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
442
was inconsistent. In the error case, msg may be set but then points to a
443
static string (which must not be deallocated).
444
*/
445
446
/* Advanced functions */
447
448
/*
449
The following functions are needed only in some special applications.
450
*/
451
452
/*
453
ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
454
int level,
455
int method,
456
int windowBits,
457
int memLevel,
458
int strategy));
459
460
This is another version of deflateInit with more compression options. The
461
fields next_in, zalloc, zfree and opaque must be initialized before by
462
the caller.
463
464
The method parameter is the compression method. It must be Z_DEFLATED in
465
this version of the library.
466
467
The windowBits parameter is the base two logarithm of the window size
468
(the size of the history buffer). It should be in the range 8..15 for this
469
version of the library. Larger values of this parameter result in better
470
compression at the expense of memory usage. The default value is 15 if
471
deflateInit is used instead.
472
473
windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
474
determines the window size. deflate() will then generate raw deflate data
475
with no zlib header or trailer, and will not compute an adler32 check value.
476
477
windowBits can also be greater than 15 for optional gzip encoding. Add
478
16 to windowBits to write a simple gzip header and trailer around the
479
compressed data instead of a zlib wrapper. The gzip header will have no
480
file name, no extra data, no comment, no modification time (set to zero),
481
no header crc, and the operating system will be set to 255 (unknown).
482
483
The memLevel parameter specifies how much memory should be allocated
484
for the internal compression state. memLevel=1 uses minimum memory but
485
is slow and reduces compression ratio; memLevel=9 uses maximum memory
486
for optimal speed. The default value is 8. See zconf.h for total memory
487
usage as a function of windowBits and memLevel.
488
489
The strategy parameter is used to tune the compression algorithm. Use the
490
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
491
filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
492
string match), or Z_RLE to limit match distances to one (run-length
493
encoding). Filtered data consists mostly of small values with a somewhat
494
random distribution. In this case, the compression algorithm is tuned to
495
compress them better. The effect of Z_FILTERED is to force more Huffman
496
coding and less string matching; it is somewhat intermediate between
497
Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
498
Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
499
parameter only affects the compression ratio but not the correctness of the
500
compressed output even if it is not set appropriately.
501
502
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
503
memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
504
method). msg is set to null if there is no error message. deflateInit2 does
505
not perform any compression: this will be done by deflate().
506
*/
507
508
ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
509
const Bytef *dictionary,
510
uInt dictLength));
511
/*
512
Initializes the compression dictionary from the given byte sequence
513
without producing any compressed output. This function must be called
514
immediately after deflateInit, deflateInit2 or deflateReset, before any
515
call of deflate. The compressor and decompressor must use exactly the same
516
dictionary (see inflateSetDictionary).
517
518
The dictionary should consist of strings (byte sequences) that are likely
519
to be encountered later in the data to be compressed, with the most commonly
520
used strings preferably put towards the end of the dictionary. Using a
521
dictionary is most useful when the data to be compressed is short and can be
522
predicted with good accuracy; the data can then be compressed better than
523
with the default empty dictionary.
524
525
Depending on the size of the compression data structures selected by
526
deflateInit or deflateInit2, a part of the dictionary may in effect be
527
discarded, for example if the dictionary is larger than the window size in
528
deflate or deflate2. Thus the strings most likely to be useful should be
529
put at the end of the dictionary, not at the front.
530
531
Upon return of this function, strm->adler is set to the adler32 value
532
of the dictionary; the decompressor may later use this value to determine
533
which dictionary has been used by the compressor. (The adler32 value
534
applies to the whole dictionary even if only a subset of the dictionary is
535
actually used by the compressor.) If a raw deflate was requested, then the
536
adler32 value is not computed and strm->adler is not set.
537
538
deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
539
parameter is invalid (such as NULL dictionary) or the stream state is
540
inconsistent (for example if deflate has already been called for this stream
541
or if the compression method is bsort). deflateSetDictionary does not
542
perform any compression: this will be done by deflate().
543
*/
544
545
ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
546
z_streamp source));
547
/*
548
Sets the destination stream as a complete copy of the source stream.
549
550
This function can be useful when several compression strategies will be
551
tried, for example when there are several ways of pre-processing the input
552
data with a filter. The streams that will be discarded should then be freed
553
by calling deflateEnd. Note that deflateCopy duplicates the internal
554
compression state which can be quite large, so this strategy is slow and
555
can consume lots of memory.
556
557
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
558
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
559
(such as zalloc being NULL). msg is left unchanged in both source and
560
destination.
561
*/
562
563
ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
564
/*
565
This function is equivalent to deflateEnd followed by deflateInit,
566
but does not free and reallocate all the internal compression state.
567
The stream will keep the same compression level and any other attributes
568
that may have been set by deflateInit2.
569
570
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
571
stream state was inconsistent (such as zalloc or state being NULL).
572
*/
573
574
ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
575
int level,
576
int strategy));
577
/*
578
Dynamically update the compression level and compression strategy. The
579
interpretation of level and strategy is as in deflateInit2. This can be
580
used to switch between compression and straight copy of the input data, or
581
to switch to a different kind of input data requiring a different
582
strategy. If the compression level is changed, the input available so far
583
is compressed with the old level (and may be flushed); the new level will
584
take effect only at the next call of deflate().
585
586
Before the call of deflateParams, the stream state must be set as for
587
a call of deflate(), since the currently available input may have to
588
be compressed and flushed. In particular, strm->avail_out must be non-zero.
589
590
deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
591
stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
592
if strm->avail_out was zero.
593
*/
594
595
ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
596
uLong sourceLen));
597
/*
598
deflateBound() returns an upper bound on the compressed size after
599
deflation of sourceLen bytes. It must be called after deflateInit()
600
or deflateInit2(). This would be used to allocate an output buffer
601
for deflation in a single pass, and so would be called before deflate().
602
*/
603
604
ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
605
int bits,
606
int value));
607
/*
608
deflatePrime() inserts bits in the deflate output stream. The intent
609
is that this function is used to start off the deflate output with the
610
bits leftover from a previous deflate stream when appending to it. As such,
611
this function can only be used for raw deflate, and must be used before the
612
first deflate() call after a deflateInit2() or deflateReset(). bits must be
613
less than or equal to 16, and that many of the least significant bits of
614
value will be inserted in the output.
615
616
deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
617
stream state was inconsistent.
618
*/
619
620
/*
621
ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
622
int windowBits));
623
624
This is another version of inflateInit with an extra parameter. The
625
fields next_in, avail_in, zalloc, zfree and opaque must be initialized
626
before by the caller.
627
628
The windowBits parameter is the base two logarithm of the maximum window
629
size (the size of the history buffer). It should be in the range 8..15 for
630
this version of the library. The default value is 15 if inflateInit is used
631
instead. windowBits must be greater than or equal to the windowBits value
632
provided to deflateInit2() while compressing, or it must be equal to 15 if
633
deflateInit2() was not used. If a compressed stream with a larger window
634
size is given as input, inflate() will return with the error code
635
Z_DATA_ERROR instead of trying to allocate a larger window.
636
637
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
638
determines the window size. inflate() will then process raw deflate data,
639
not looking for a zlib or gzip header, not generating a check value, and not
640
looking for any check values for comparison at the end of the stream. This
641
is for use with other formats that use the deflate compressed data format
642
such as zip. Those formats provide their own check values. If a custom
643
format is developed using the raw deflate format for compressed data, it is
644
recommended that a check value such as an adler32 or a crc32 be applied to
645
the uncompressed data as is done in the zlib, gzip, and zip formats. For
646
most applications, the zlib format should be used as is. Note that comments
647
above on the use in deflateInit2() applies to the magnitude of windowBits.
648
649
windowBits can also be greater than 15 for optional gzip decoding. Add
650
32 to windowBits to enable zlib and gzip decoding with automatic header
651
detection, or add 16 to decode only the gzip format (the zlib format will
652
return a Z_DATA_ERROR).
653
654
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
655
memory, Z_STREAM_ERROR if a parameter is invalid (such as a negative
656
memLevel). msg is set to null if there is no error message. inflateInit2
657
does not perform any decompression apart from reading the zlib header if
658
present: this will be done by inflate(). (So next_in and avail_in may be
659
modified, but next_out and avail_out are unchanged.)
660
*/
661
662
ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
663
const Bytef *dictionary,
664
uInt dictLength));
665
/*
666
Initializes the decompression dictionary from the given uncompressed byte
667
sequence. This function must be called immediately after a call of inflate
668
if this call returned Z_NEED_DICT. The dictionary chosen by the compressor
669
can be determined from the adler32 value returned by this call of
670
inflate. The compressor and decompressor must use exactly the same
671
dictionary (see deflateSetDictionary).
672
673
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
674
parameter is invalid (such as NULL dictionary) or the stream state is
675
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
676
expected one (incorrect adler32 value). inflateSetDictionary does not
677
perform any decompression: this will be done by subsequent calls of
678
inflate().
679
*/
680
681
ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
682
/*
683
Skips invalid compressed data until a full flush point (see above the
684
description of deflate with Z_FULL_FLUSH) can be found, or until all
685
available input is skipped. No output is provided.
686
687
inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
688
if no more input was provided, Z_DATA_ERROR if no flush point has been found,
689
or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
690
case, the application may save the current current value of total_in which
691
indicates where valid compressed data was found. In the error case, the
692
application may repeatedly call inflateSync, providing more input each time,
693
until success or end of the input data.
694
*/
695
696
ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
697
z_streamp source));
698
/*
699
Sets the destination stream as a complete copy of the source stream.
700
701
This function can be useful when randomly accessing a large stream. The
702
first pass through the stream can periodically record the inflate state,
703
allowing restarting inflate at those points when randomly accessing the
704
stream.
705
706
inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
707
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
708
(such as zalloc being NULL). msg is left unchanged in both source and
709
destination.
710
*/
711
712
ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
713
/*
714
This function is equivalent to inflateEnd followed by inflateInit,
715
but does not free and reallocate all the internal decompression state.
716
The stream will keep attributes that may have been set by inflateInit2.
717
718
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
719
stream state was inconsistent (such as zalloc or state being NULL).
720
*/
721
722
/*
723
ZEXTERN int ZEXPORT inflateBackInit OF((z_stream FAR *strm, int windowBits,
724
unsigned char FAR *window));
725
726
Initialize the internal stream state for decompression using inflateBack()
727
calls. The fields zalloc, zfree and opaque in strm must be initialized
728
before the call. If zalloc and zfree are Z_NULL, then the default library-
729
derived memory allocation routines are used. windowBits is the base two
730
logarithm of the window size, in the range 8..15. window is a caller
731
supplied buffer of that size. Except for special applications where it is
732
assured that deflate was used with small window sizes, windowBits must be 15
733
and a 32K byte window must be supplied to be able to decompress general
734
deflate streams.
735
736
See inflateBack() for the usage of these routines.
737
738
inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
739
the paramaters are invalid, Z_MEM_ERROR if the internal state could not
740
be allocated, or Z_VERSION_ERROR if the version of the library does not
741
match the version of the header file.
742
*/
743
744
typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
745
typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
746
747
ZEXTERN int ZEXPORT inflateBack OF((z_stream FAR *strm,
748
in_func in, void FAR *in_desc,
749
out_func out, void FAR *out_desc));
750
/*
751
inflateBack() does a raw inflate with a single call using a call-back
752
interface for input and output. This is more efficient than inflate() for
753
file i/o applications in that it avoids copying between the output and the
754
sliding window by simply making the window itself the output buffer. This
755
function trusts the application to not change the output buffer passed by
756
the output function, at least until inflateBack() returns.
757
758
inflateBackInit() must be called first to allocate the internal state
759
and to initialize the state with the user-provided window buffer.
760
inflateBack() may then be used multiple times to inflate a complete, raw
761
deflate stream with each call. inflateBackEnd() is then called to free
762
the allocated state.
763
764
A raw deflate stream is one with no zlib or gzip header or trailer.
765
This routine would normally be used in a utility that reads zip or gzip
766
files and writes out uncompressed files. The utility would decode the
767
header and process the trailer on its own, hence this routine expects
768
only the raw deflate stream to decompress. This is different from the
769
normal behavior of inflate(), which expects either a zlib or gzip header and
770
trailer around the deflate stream.
771
772
inflateBack() uses two subroutines supplied by the caller that are then
773
called by inflateBack() for input and output. inflateBack() calls those
774
routines until it reads a complete deflate stream and writes out all of the
775
uncompressed data, or until it encounters an error. The function's
776
parameters and return types are defined above in the in_func and out_func
777
typedefs. inflateBack() will call in(in_desc, &buf) which should return the
778
number of bytes of provided input, and a pointer to that input in buf. If
779
there is no input available, in() must return zero--buf is ignored in that
780
case--and inflateBack() will return a buffer error. inflateBack() will call
781
out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
782
should return zero on success, or non-zero on failure. If out() returns
783
non-zero, inflateBack() will return with an error. Neither in() nor out()
784
are permitted to change the contents of the window provided to
785
inflateBackInit(), which is also the buffer that out() uses to write from.
786
The length written by out() will be at most the window size. Any non-zero
787
amount of input may be provided by in().
788
789
For convenience, inflateBack() can be provided input on the first call by
790
setting strm->next_in and strm->avail_in. If that input is exhausted, then
791
in() will be called. Therefore strm->next_in must be initialized before
792
calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
793
immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
794
must also be initialized, and then if strm->avail_in is not zero, input will
795
initially be taken from strm->next_in[0 .. strm->avail_in - 1].
796
797
The in_desc and out_desc parameters of inflateBack() is passed as the
798
first parameter of in() and out() respectively when they are called. These
799
descriptors can be optionally used to pass any information that the caller-
800
supplied in() and out() functions need to do their job.
801
802
On return, inflateBack() will set strm->next_in and strm->avail_in to
803
pass back any unused input that was provided by the last in() call. The
804
return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
805
if in() or out() returned an error, Z_DATA_ERROR if there was a format
806
error in the deflate stream (in which case strm->msg is set to indicate the
807
nature of the error), or Z_STREAM_ERROR if the stream was not properly
808
initialized. In the case of Z_BUF_ERROR, an input or output error can be
809
distinguished using strm->next_in which will be Z_NULL only if in() returned
810
an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
811
out() returning non-zero. (in() will always be called before out(), so
812
strm->next_in is assured to be defined if out() returns non-zero.) Note
813
that inflateBack() cannot return Z_OK.
814
*/
815
816
ZEXTERN int ZEXPORT inflateBackEnd OF((z_stream FAR *strm));
817
/*
818
All memory allocated by inflateBackInit() is freed.
819
820
inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
821
state was inconsistent.
822
*/
823
824
ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
825
/* Return flags indicating compile-time options.
826
827
Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
828
1.0: size of uInt
829
3.2: size of uLong
830
5.4: size of voidpf (pointer)
831
7.6: size of z_off_t
832
833
Compiler, assembler, and debug options:
834
8: DEBUG
835
9: ASMV or ASMINF -- use ASM code
836
10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
837
11: 0 (reserved)
838
839
One-time table building (smaller code, but not thread-safe if true):
840
12: BUILDFIXED -- build static block decoding tables when needed
841
13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
842
14,15: 0 (reserved)
843
844
Library content (indicates missing functionality):
845
16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
846
deflate code when not needed)
847
17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
848
and decode gzip streams (to avoid linking crc code)
849
18-19: 0 (reserved)
850
851
Operation variations (changes in library functionality):
852
20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
853
21: FASTEST -- deflate algorithm with only one, lowest compression level
854
22,23: 0 (reserved)
855
856
The sprintf variant used by gzprintf (zero is best):
857
24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
858
25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
859
26: 0 = returns value, 1 = void -- 1 means inferred string length returned
860
861
Remainder:
862
27-31: 0 (reserved)
863
*/
864
865
866
/* utility functions */
867
868
/*
869
The following utility functions are implemented on top of the
870
basic stream-oriented functions. To simplify the interface, some
871
default options are assumed (compression level and memory usage,
872
standard memory allocation functions). The source code of these
873
utility functions can easily be modified if you need special options.
874
*/
875
876
ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
877
const Bytef *source, uLong sourceLen));
878
/*
879
Compresses the source buffer into the destination buffer. sourceLen is
880
the byte length of the source buffer. Upon entry, destLen is the total
881
size of the destination buffer, which must be at least the value returned
882
by compressBound(sourceLen). Upon exit, destLen is the actual size of the
883
compressed buffer.
884
This function can be used to compress a whole file at once if the
885
input file is mmap'ed.
886
compress returns Z_OK if success, Z_MEM_ERROR if there was not
887
enough memory, Z_BUF_ERROR if there was not enough room in the output
888
buffer.
889
*/
890
891
ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
892
const Bytef *source, uLong sourceLen,
893
int level));
894
/*
895
Compresses the source buffer into the destination buffer. The level
896
parameter has the same meaning as in deflateInit. sourceLen is the byte
897
length of the source buffer. Upon entry, destLen is the total size of the
898
destination buffer, which must be at least the value returned by
899
compressBound(sourceLen). Upon exit, destLen is the actual size of the
900
compressed buffer.
901
902
compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
903
memory, Z_BUF_ERROR if there was not enough room in the output buffer,
904
Z_STREAM_ERROR if the level parameter is invalid.
905
*/
906
907
ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
908
/*
909
compressBound() returns an upper bound on the compressed size after
910
compress() or compress2() on sourceLen bytes. It would be used before
911
a compress() or compress2() call to allocate the destination buffer.
912
*/
913
914
ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
915
const Bytef *source, uLong sourceLen));
916
/*
917
Decompresses the source buffer into the destination buffer. sourceLen is
918
the byte length of the source buffer. Upon entry, destLen is the total
919
size of the destination buffer, which must be large enough to hold the
920
entire uncompressed data. (The size of the uncompressed data must have
921
been saved previously by the compressor and transmitted to the decompressor
922
by some mechanism outside the scope of this compression library.)
923
Upon exit, destLen is the actual size of the compressed buffer.
924
This function can be used to decompress a whole file at once if the
925
input file is mmap'ed.
926
927
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
928
enough memory, Z_BUF_ERROR if there was not enough room in the output
929
buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
930
*/
931
932
933
typedef voidp gzFile;
934
935
ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
936
/*
937
Opens a gzip (.gz) file for reading or writing. The mode parameter
938
is as in fopen ("rb" or "wb") but can also include a compression level
939
("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
940
Huffman only compression as in "wb1h", or 'R' for run-length encoding
941
as in "wb1R". (See the description of deflateInit2 for more information
942
about the strategy parameter.)
943
944
gzopen can be used to read a file which is not in gzip format; in this
945
case gzread will directly read from the file without decompression.
946
947
gzopen returns NULL if the file could not be opened or if there was
948
insufficient memory to allocate the (de)compression state; errno
949
can be checked to distinguish the two cases (if errno is zero, the
950
zlib error is Z_MEM_ERROR). */
951
952
ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
953
/*
954
gzdopen() associates a gzFile with the file descriptor fd. File
955
descriptors are obtained from calls like open, dup, creat, pipe or
956
fileno (in the file has been previously opened with fopen).
957
The mode parameter is as in gzopen.
958
The next call of gzclose on the returned gzFile will also close the
959
file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
960
descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
961
gzdopen returns NULL if there was insufficient memory to allocate
962
the (de)compression state.
963
*/
964
965
ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
966
/*
967
Dynamically update the compression level or strategy. See the description
968
of deflateInit2 for the meaning of these parameters.
969
gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
970
opened for writing.
971
*/
972
973
ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
974
/*
975
Reads the given number of uncompressed bytes from the compressed file.
976
If the input file was not in gzip format, gzread copies the given number
977
of bytes into the buffer.
978
gzread returns the number of uncompressed bytes actually read (0 for
979
end of file, -1 for error). */
980
981
ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
982
voidpc buf, unsigned len));
983
/*
984
Writes the given number of uncompressed bytes into the compressed file.
985
gzwrite returns the number of uncompressed bytes actually written
986
(0 in case of error).
987
*/
988
989
ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
990
/*
991
Converts, formats, and writes the args to the compressed file under
992
control of the format string, as in fprintf. gzprintf returns the number of
993
uncompressed bytes actually written (0 in case of error). The number of
994
uncompressed bytes written is limited to 4095. The caller should assure that
995
this limit is not exceeded. If it is exceeded, then gzprintf() will return
996
return an error (0) with nothing written. In this case, there may also be a
997
buffer overflow with unpredictable consequences, which is possible only if
998
zlib was compiled with the insecure functions sprintf() or vsprintf()
999
because the secure snprintf() or vsnprintf() functions were not available.
1000
*/
1001
1002
ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1003
/*
1004
Writes the given null-terminated string to the compressed file, excluding
1005
the terminating null character.
1006
gzputs returns the number of characters written, or -1 in case of error.
1007
*/
1008
1009
ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1010
/*
1011
Reads bytes from the compressed file until len-1 characters are read, or
1012
a newline character is read and transferred to buf, or an end-of-file
1013
condition is encountered. The string is then terminated with a null
1014
character.
1015
gzgets returns buf, or Z_NULL in case of error.
1016
*/
1017
1018
ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1019
/*
1020
Writes c, converted to an unsigned char, into the compressed file.
1021
gzputc returns the value that was written, or -1 in case of error.
1022
*/
1023
1024
ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1025
/*
1026
Reads one byte from the compressed file. gzgetc returns this byte
1027
or -1 in case of end of file or error.
1028
*/
1029
1030
ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1031
/*
1032
Push one character back onto the stream to be read again later.
1033
Only one character of push-back is allowed. gzungetc() returns the
1034
character pushed, or -1 on failure. gzungetc() will fail if a
1035
character has been pushed but not read yet, or if c is -1. The pushed
1036
character will be discarded if the stream is repositioned with gzseek()
1037
or gzrewind().
1038
*/
1039
1040
ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1041
/*
1042
Flushes all pending output into the compressed file. The parameter
1043
flush is as in the deflate() function. The return value is the zlib
1044
error number (see function gzerror below). gzflush returns Z_OK if
1045
the flush parameter is Z_FINISH and all output could be flushed.
1046
gzflush should be called only when strictly necessary because it can
1047
degrade compression.
1048
*/
1049
1050
ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1051
z_off_t offset, int whence));
1052
/*
1053
Sets the starting position for the next gzread or gzwrite on the
1054
given compressed file. The offset represents a number of bytes in the
1055
uncompressed data stream. The whence parameter is defined as in lseek(2);
1056
the value SEEK_END is not supported.
1057
If the file is opened for reading, this function is emulated but can be
1058
extremely slow. If the file is opened for writing, only forward seeks are
1059
supported; gzseek then compresses a sequence of zeroes up to the new
1060
starting position.
1061
1062
gzseek returns the resulting offset location as measured in bytes from
1063
the beginning of the uncompressed stream, or -1 in case of error, in
1064
particular if the file is opened for writing and the new starting position
1065
would be before the current position.
1066
*/
1067
1068
ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1069
/*
1070
Rewinds the given file. This function is supported only for reading.
1071
1072
gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1073
*/
1074
1075
ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1076
/*
1077
Returns the starting position for the next gzread or gzwrite on the
1078
given compressed file. This position represents a number of bytes in the
1079
uncompressed data stream.
1080
1081
gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1082
*/
1083
1084
ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1085
/*
1086
Returns 1 when EOF has previously been detected reading the given
1087
input stream, otherwise zero.
1088
*/
1089
1090
ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1091
/*
1092
Flushes all pending output if necessary, closes the compressed file
1093
and deallocates all the (de)compression state. The return value is the zlib
1094
error number (see function gzerror below).
1095
*/
1096
1097
ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1098
/*
1099
Returns the error message for the last error which occurred on the
1100
given compressed file. errnum is set to zlib error number. If an
1101
error occurred in the file system and not in the compression library,
1102
errnum is set to Z_ERRNO and the application may consult errno
1103
to get the exact error code.
1104
*/
1105
1106
ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1107
/*
1108
Clears the error and end-of-file flags for file. This is analogous to the
1109
clearerr() function in stdio. This is useful for continuing to read a gzip
1110
file that is being written concurrently.
1111
*/
1112
1113
/* checksum functions */
1114
1115
/*
1116
These functions are not related to compression but are exported
1117
anyway because they might be useful in applications using the
1118
compression library.
1119
*/
1120
1121
ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1122
1123
/*
1124
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1125
return the updated checksum. If buf is NULL, this function returns
1126
the required initial value for the checksum.
1127
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1128
much faster. Usage example:
1129
1130
uLong adler = adler32(0L, Z_NULL, 0);
1131
1132
while (read_buffer(buffer, length) != EOF) {
1133
adler = adler32(adler, buffer, length);
1134
}
1135
if (adler != original_adler) error();
1136
*/
1137
1138
ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1139
/*
1140
Update a running crc with the bytes buf[0..len-1] and return the updated
1141
crc. If buf is NULL, this function returns the required initial value
1142
for the crc. Pre- and post-conditioning (one's complement) is performed
1143
within this function so it shouldn't be done by the application.
1144
Usage example:
1145
1146
uLong crc = crc32(0L, Z_NULL, 0);
1147
1148
while (read_buffer(buffer, length) != EOF) {
1149
crc = crc32(crc, buffer, length);
1150
}
1151
if (crc != original_crc) error();
1152
*/
1153
1154
1155
/* various hacks, don't look :) */
1156
1157
/* deflateInit and inflateInit are macros to allow checking the zlib version
1158
* and the compiler's view of z_stream:
1159
*/
1160
ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1161
const char *version, int stream_size));
1162
ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1163
const char *version, int stream_size));
1164
ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1165
int windowBits, int memLevel,
1166
int strategy, const char *version,
1167
int stream_size));
1168
ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1169
const char *version, int stream_size));
1170
ZEXTERN int ZEXPORT inflateBackInit_ OF((z_stream FAR *strm, int windowBits,
1171
unsigned char FAR *window,
1172
const char *version,
1173
int stream_size));
1174
#define deflateInit(strm, level) \
1175
deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
1176
#define inflateInit(strm) \
1177
inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
1178
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1179
deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1180
(strategy), ZLIB_VERSION, sizeof(z_stream))
1181
#define inflateInit2(strm, windowBits) \
1182
inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
1183
#define inflateBackInit(strm, windowBits, window) \
1184
inflateBackInit_((strm), (windowBits), (window), \
1185
ZLIB_VERSION, sizeof(z_stream))
1186
1187
1188
#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1189
struct internal_state {int dummy;}; /* hack for buggy compilers */
1190
#endif
1191
1192
ZEXTERN const char * ZEXPORT zError OF((int err));
1193
ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
1194
ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
1195
1196
#ifdef __cplusplus
1197
}
1198
#endif
1199
1200
#endif /* ZLIB_H */
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