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- Committer: zaka62
- Author(s): Kicad developers team.
- Date: 2012-05-04 16:10:32 UTC
- mfrom: (3480.1.60 testing)
- Revision ID: zaka62@mail.ru-20120504161032-c5lnbcyhhbt9fn4z
Merge upstream changes from the 3540 commit.
- files added:
- common/common_plotPDF_functions.cpp
- import
- import/edif2kicad
- import/edif2kicad/examples
- import/edif2kicad/test
- import/pcb123net2kicad
- zlib
- files modified:
- .bzrignore
added
removed
zlib/zlib.h
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/* zlib.h -- interface of the 'zlib' general purpose compression library
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version 1.2.3, July 18th, 2005
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Copyright (C) 1995-2005 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 "1.2.3"
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#define ZLIB_VERNUM 0x1230
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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 default by the in-memory functions is
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the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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around a 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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This library can optionally read and write gzip streams in memory as well.
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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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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: binary or text */
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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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gzip header information passed to and from zlib routines. See RFC 1952
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for more details on the meanings of these fields.
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*/
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typedef struct gz_header_s {
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int text; /* true if compressed data believed to be text */
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uLong time; /* modification time */
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int xflags; /* extra flags (not used when writing a gzip file) */
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int os; /* operating system */
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Bytef *extra; /* pointer to extra field or Z_NULL if none */
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uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
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uInt extra_max; /* space at extra (only when reading header) */
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Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
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uInt name_max; /* space at name (only when reading header) */
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Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
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uInt comm_max; /* space at comment (only when reading header) */
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int hcrc; /* true if there was or will be a header crc */
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int done; /* true when done reading gzip header (not used
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when writing a gzip file) */
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} gz_header;
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typedef gz_header FAR *gz_headerp;
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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_FIXED 4
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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_TEXT 1
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#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
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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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Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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decide how much data to accumualte before producing output, in order to
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maximize compression.
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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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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 strm->data_type if it can make a good guess about
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the input data type (Z_BINARY or Z_TEXT). 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
321
if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
322
(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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/*
330
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
335
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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/*
343
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
348
value depends on the compression method), inflateInit determines the
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compression method from the zlib header and allocates all data structures
350
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
356
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.)
360
*/
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ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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/*
365
inflate decompresses 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
367
some output latency (reading input without producing any output) except when
368
forced to flush.
369
370
The detailed semantics are as follows. inflate performs one or both of the
371
following actions:
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373
- Decompress more input starting at next_in and update next_in and avail_in
374
accordingly. If not all input can be processed (because there is not
375
enough room in the output buffer), next_in is updated and processing
376
will resume at this point for the next call of inflate().
377
378
- Provide more output starting at next_out and update next_out and avail_out
379
accordingly. inflate() provides as much output as possible, until there
380
is no more input data or no more space in the output buffer (see below
381
about the flush parameter).
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Before the call of inflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming
385
more output, and updating the next_* and avail_* values accordingly.
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The application can consume the uncompressed output when it wants, for
387
example when the output buffer is full (avail_out == 0), or after each
388
call of inflate(). If inflate returns Z_OK and with zero avail_out, it
389
must be called again after making room in the output buffer because there
390
might be more output pending.
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392
The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
393
Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
394
output as possible to the output buffer. Z_BLOCK requests that inflate() stop
395
if and when it gets to the next deflate block boundary. When decoding the
396
zlib or gzip format, this will cause inflate() to return immediately after
397
the header and before the first block. When doing a raw inflate, inflate()
398
will go ahead and process the first block, and will return when it gets to
399
the end of that block, or when it runs out of data.
400
401
The Z_BLOCK option assists in appending to or combining deflate streams.
402
Also to assist in this, on return inflate() will set strm->data_type to the
403
number of unused bits in the last byte taken from strm->next_in, plus 64
404
if inflate() is currently decoding the last block in the deflate stream,
405
plus 128 if inflate() returned immediately after decoding an end-of-block
406
code or decoding the complete header up to just before the first byte of the
407
deflate stream. The end-of-block will not be indicated until all of the
408
uncompressed data from that block has been written to strm->next_out. The
409
number of unused bits may in general be greater than seven, except when
410
bit 7 of data_type is set, in which case the number of unused bits will be
411
less than eight.
412
413
inflate() should normally be called until it returns Z_STREAM_END or an
414
error. However if all decompression is to be performed in a single step
415
(a single call of inflate), the parameter flush should be set to
416
Z_FINISH. In this case all pending input is processed and all pending
417
output is flushed; avail_out must be large enough to hold all the
418
uncompressed data. (The size of the uncompressed data may have been saved
419
by the compressor for this purpose.) The next operation on this stream must
420
be inflateEnd to deallocate the decompression state. The use of Z_FINISH
421
is never required, but can be used to inform inflate that a faster approach
422
may be used for the single inflate() call.
423
424
In this implementation, inflate() always flushes as much output as
425
possible to the output buffer, and always uses the faster approach on the
426
first call. So the only effect of the flush parameter in this implementation
427
is on the return value of inflate(), as noted below, or when it returns early
428
because Z_BLOCK is used.
429
430
If a preset dictionary is needed after this call (see inflateSetDictionary
431
below), inflate sets strm->adler to the adler32 checksum of the dictionary
432
chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
433
strm->adler to the adler32 checksum of all output produced so far (that is,
434
total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
435
below. At the end of the stream, inflate() checks that its computed adler32
436
checksum is equal to that saved by the compressor and returns Z_STREAM_END
437
only if the checksum is correct.
438
439
inflate() will decompress and check either zlib-wrapped or gzip-wrapped
440
deflate data. The header type is detected automatically. Any information
441
contained in the gzip header is not retained, so applications that need that
442
information should instead use raw inflate, see inflateInit2() below, or
443
inflateBack() and perform their own processing of the gzip header and
444
trailer.
445
446
inflate() returns Z_OK if some progress has been made (more input processed
447
or more output produced), Z_STREAM_END if the end of the compressed data has
448
been reached and all uncompressed output has been produced, Z_NEED_DICT if a
449
preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
450
corrupted (input stream not conforming to the zlib format or incorrect check
451
value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
452
if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
453
Z_BUF_ERROR if no progress is possible or if there was not enough room in the
454
output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
455
inflate() can be called again with more input and more output space to
456
continue decompressing. If Z_DATA_ERROR is returned, the application may then
457
call inflateSync() to look for a good compression block if a partial recovery
458
of the data is desired.
459
*/
460
461
462
ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
463
/*
464
All dynamically allocated data structures for this stream are freed.
465
This function discards any unprocessed input and does not flush any
466
pending output.
467
468
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
469
was inconsistent. In the error case, msg may be set but then points to a
470
static string (which must not be deallocated).
471
*/
472
473
/* Advanced functions */
474
475
/*
476
The following functions are needed only in some special applications.
477
*/
478
479
/*
480
ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
481
int level,
482
int method,
483
int windowBits,
484
int memLevel,
485
int strategy));
486
487
This is another version of deflateInit with more compression options. The
488
fields next_in, zalloc, zfree and opaque must be initialized before by
489
the caller.
490
491
The method parameter is the compression method. It must be Z_DEFLATED in
492
this version of the library.
493
494
The windowBits parameter is the base two logarithm of the window size
495
(the size of the history buffer). It should be in the range 8..15 for this
496
version of the library. Larger values of this parameter result in better
497
compression at the expense of memory usage. The default value is 15 if
498
deflateInit is used instead.
499
500
windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
501
determines the window size. deflate() will then generate raw deflate data
502
with no zlib header or trailer, and will not compute an adler32 check value.
503
504
windowBits can also be greater than 15 for optional gzip encoding. Add
505
16 to windowBits to write a simple gzip header and trailer around the
506
compressed data instead of a zlib wrapper. The gzip header will have no
507
file name, no extra data, no comment, no modification time (set to zero),
508
no header crc, and the operating system will be set to 255 (unknown). If a
509
gzip stream is being written, strm->adler is a crc32 instead of an adler32.
510
511
The memLevel parameter specifies how much memory should be allocated
512
for the internal compression state. memLevel=1 uses minimum memory but
513
is slow and reduces compression ratio; memLevel=9 uses maximum memory
514
for optimal speed. The default value is 8. See zconf.h for total memory
515
usage as a function of windowBits and memLevel.
516
517
The strategy parameter is used to tune the compression algorithm. Use the
518
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
519
filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
520
string match), or Z_RLE to limit match distances to one (run-length
521
encoding). Filtered data consists mostly of small values with a somewhat
522
random distribution. In this case, the compression algorithm is tuned to
523
compress them better. The effect of Z_FILTERED is to force more Huffman
524
coding and less string matching; it is somewhat intermediate between
525
Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
526
Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
527
parameter only affects the compression ratio but not the correctness of the
528
compressed output even if it is not set appropriately. Z_FIXED prevents the
529
use of dynamic Huffman codes, allowing for a simpler decoder for special
530
applications.
531
532
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
533
memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
534
method). msg is set to null if there is no error message. deflateInit2 does
535
not perform any compression: this will be done by deflate().
536
*/
537
538
ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
539
const Bytef *dictionary,
540
uInt dictLength));
541
/*
542
Initializes the compression dictionary from the given byte sequence
543
without producing any compressed output. This function must be called
544
immediately after deflateInit, deflateInit2 or deflateReset, before any
545
call of deflate. The compressor and decompressor must use exactly the same
546
dictionary (see inflateSetDictionary).
547
548
The dictionary should consist of strings (byte sequences) that are likely
549
to be encountered later in the data to be compressed, with the most commonly
550
used strings preferably put towards the end of the dictionary. Using a
551
dictionary is most useful when the data to be compressed is short and can be
552
predicted with good accuracy; the data can then be compressed better than
553
with the default empty dictionary.
554
555
Depending on the size of the compression data structures selected by
556
deflateInit or deflateInit2, a part of the dictionary may in effect be
557
discarded, for example if the dictionary is larger than the window size in
558
deflate or deflate2. Thus the strings most likely to be useful should be
559
put at the end of the dictionary, not at the front. In addition, the
560
current implementation of deflate will use at most the window size minus
561
262 bytes of the provided dictionary.
562
563
Upon return of this function, strm->adler is set to the adler32 value
564
of the dictionary; the decompressor may later use this value to determine
565
which dictionary has been used by the compressor. (The adler32 value
566
applies to the whole dictionary even if only a subset of the dictionary is
567
actually used by the compressor.) If a raw deflate was requested, then the
568
adler32 value is not computed and strm->adler is not set.
569
570
deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
571
parameter is invalid (such as NULL dictionary) or the stream state is
572
inconsistent (for example if deflate has already been called for this stream
573
or if the compression method is bsort). deflateSetDictionary does not
574
perform any compression: this will be done by deflate().
575
*/
576
577
ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
578
z_streamp source));
579
/*
580
Sets the destination stream as a complete copy of the source stream.
581
582
This function can be useful when several compression strategies will be
583
tried, for example when there are several ways of pre-processing the input
584
data with a filter. The streams that will be discarded should then be freed
585
by calling deflateEnd. Note that deflateCopy duplicates the internal
586
compression state which can be quite large, so this strategy is slow and
587
can consume lots of memory.
588
589
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
590
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
591
(such as zalloc being NULL). msg is left unchanged in both source and
592
destination.
593
*/
594
595
ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
596
/*
597
This function is equivalent to deflateEnd followed by deflateInit,
598
but does not free and reallocate all the internal compression state.
599
The stream will keep the same compression level and any other attributes
600
that may have been set by deflateInit2.
601
602
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
603
stream state was inconsistent (such as zalloc or state being NULL).
604
*/
605
606
ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
607
int level,
608
int strategy));
609
/*
610
Dynamically update the compression level and compression strategy. The
611
interpretation of level and strategy is as in deflateInit2. This can be
612
used to switch between compression and straight copy of the input data, or
613
to switch to a different kind of input data requiring a different
614
strategy. If the compression level is changed, the input available so far
615
is compressed with the old level (and may be flushed); the new level will
616
take effect only at the next call of deflate().
617
618
Before the call of deflateParams, the stream state must be set as for
619
a call of deflate(), since the currently available input may have to
620
be compressed and flushed. In particular, strm->avail_out must be non-zero.
621
622
deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
623
stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
624
if strm->avail_out was zero.
625
*/
626
627
ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
628
int good_length,
629
int max_lazy,
630
int nice_length,
631
int max_chain));
632
/*
633
Fine tune deflate's internal compression parameters. This should only be
634
used by someone who understands the algorithm used by zlib's deflate for
635
searching for the best matching string, and even then only by the most
636
fanatic optimizer trying to squeeze out the last compressed bit for their
637
specific input data. Read the deflate.c source code for the meaning of the
638
max_lazy, good_length, nice_length, and max_chain parameters.
639
640
deflateTune() can be called after deflateInit() or deflateInit2(), and
641
returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
642
*/
643
644
ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
645
uLong sourceLen));
646
/*
647
deflateBound() returns an upper bound on the compressed size after
648
deflation of sourceLen bytes. It must be called after deflateInit()
649
or deflateInit2(). This would be used to allocate an output buffer
650
for deflation in a single pass, and so would be called before deflate().
651
*/
652
653
ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
654
int bits,
655
int value));
656
/*
657
deflatePrime() inserts bits in the deflate output stream. The intent
658
is that this function is used to start off the deflate output with the
659
bits leftover from a previous deflate stream when appending to it. As such,
660
this function can only be used for raw deflate, and must be used before the
661
first deflate() call after a deflateInit2() or deflateReset(). bits must be
662
less than or equal to 16, and that many of the least significant bits of
663
value will be inserted in the output.
664
665
deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
666
stream state was inconsistent.
667
*/
668
669
ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
670
gz_headerp head));
671
/*
672
deflateSetHeader() provides gzip header information for when a gzip
673
stream is requested by deflateInit2(). deflateSetHeader() may be called
674
after deflateInit2() or deflateReset() and before the first call of
675
deflate(). The text, time, os, extra field, name, and comment information
676
in the provided gz_header structure are written to the gzip header (xflag is
677
ignored -- the extra flags are set according to the compression level). The
678
caller must assure that, if not Z_NULL, name and comment are terminated with
679
a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
680
available there. If hcrc is true, a gzip header crc is included. Note that
681
the current versions of the command-line version of gzip (up through version
682
1.3.x) do not support header crc's, and will report that it is a "multi-part
683
gzip file" and give up.
684
685
If deflateSetHeader is not used, the default gzip header has text false,
686
the time set to zero, and os set to 255, with no extra, name, or comment
687
fields. The gzip header is returned to the default state by deflateReset().
688
689
deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
690
stream state was inconsistent.
691
*/
692
693
/*
694
ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
695
int windowBits));
696
697
This is another version of inflateInit with an extra parameter. The
698
fields next_in, avail_in, zalloc, zfree and opaque must be initialized
699
before by the caller.
700
701
The windowBits parameter is the base two logarithm of the maximum window
702
size (the size of the history buffer). It should be in the range 8..15 for
703
this version of the library. The default value is 15 if inflateInit is used
704
instead. windowBits must be greater than or equal to the windowBits value
705
provided to deflateInit2() while compressing, or it must be equal to 15 if
706
deflateInit2() was not used. If a compressed stream with a larger window
707
size is given as input, inflate() will return with the error code
708
Z_DATA_ERROR instead of trying to allocate a larger window.
709
710
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
711
determines the window size. inflate() will then process raw deflate data,
712
not looking for a zlib or gzip header, not generating a check value, and not
713
looking for any check values for comparison at the end of the stream. This
714
is for use with other formats that use the deflate compressed data format
715
such as zip. Those formats provide their own check values. If a custom
716
format is developed using the raw deflate format for compressed data, it is
717
recommended that a check value such as an adler32 or a crc32 be applied to
718
the uncompressed data as is done in the zlib, gzip, and zip formats. For
719
most applications, the zlib format should be used as is. Note that comments
720
above on the use in deflateInit2() applies to the magnitude of windowBits.
721
722
windowBits can also be greater than 15 for optional gzip decoding. Add
723
32 to windowBits to enable zlib and gzip decoding with automatic header
724
detection, or add 16 to decode only the gzip format (the zlib format will
725
return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
726
a crc32 instead of an adler32.
727
728
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
729
memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
730
is set to null if there is no error message. inflateInit2 does not perform
731
any decompression apart from reading the zlib header if present: this will
732
be done by inflate(). (So next_in and avail_in may be modified, but next_out
733
and avail_out are unchanged.)
734
*/
735
736
ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
737
const Bytef *dictionary,
738
uInt dictLength));
739
/*
740
Initializes the decompression dictionary from the given uncompressed byte
741
sequence. This function must be called immediately after a call of inflate,
742
if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
743
can be determined from the adler32 value returned by that call of inflate.
744
The compressor and decompressor must use exactly the same dictionary (see
745
deflateSetDictionary). For raw inflate, this function can be called
746
immediately after inflateInit2() or inflateReset() and before any call of
747
inflate() to set the dictionary. The application must insure that the
748
dictionary that was used for compression is provided.
749
750
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
751
parameter is invalid (such as NULL dictionary) or the stream state is
752
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
753
expected one (incorrect adler32 value). inflateSetDictionary does not
754
perform any decompression: this will be done by subsequent calls of
755
inflate().
756
*/
757
758
ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
759
/*
760
Skips invalid compressed data until a full flush point (see above the
761
description of deflate with Z_FULL_FLUSH) can be found, or until all
762
available input is skipped. No output is provided.
763
764
inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
765
if no more input was provided, Z_DATA_ERROR if no flush point has been found,
766
or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
767
case, the application may save the current current value of total_in which
768
indicates where valid compressed data was found. In the error case, the
769
application may repeatedly call inflateSync, providing more input each time,
770
until success or end of the input data.
771
*/
772
773
ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
774
z_streamp source));
775
/*
776
Sets the destination stream as a complete copy of the source stream.
777
778
This function can be useful when randomly accessing a large stream. The
779
first pass through the stream can periodically record the inflate state,
780
allowing restarting inflate at those points when randomly accessing the
781
stream.
782
783
inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
784
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
785
(such as zalloc being NULL). msg is left unchanged in both source and
786
destination.
787
*/
788
789
ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
790
/*
791
This function is equivalent to inflateEnd followed by inflateInit,
792
but does not free and reallocate all the internal decompression state.
793
The stream will keep attributes that may have been set by inflateInit2.
794
795
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
796
stream state was inconsistent (such as zalloc or state being NULL).
797
*/
798
799
ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
800
int bits,
801
int value));
802
/*
803
This function inserts bits in the inflate input stream. The intent is
804
that this function is used to start inflating at a bit position in the
805
middle of a byte. The provided bits will be used before any bytes are used
806
from next_in. This function should only be used with raw inflate, and
807
should be used before the first inflate() call after inflateInit2() or
808
inflateReset(). bits must be less than or equal to 16, and that many of the
809
least significant bits of value will be inserted in the input.
810
811
inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
812
stream state was inconsistent.
813
*/
814
815
ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
816
gz_headerp head));
817
/*
818
inflateGetHeader() requests that gzip header information be stored in the
819
provided gz_header structure. inflateGetHeader() may be called after
820
inflateInit2() or inflateReset(), and before the first call of inflate().
821
As inflate() processes the gzip stream, head->done is zero until the header
822
is completed, at which time head->done is set to one. If a zlib stream is
823
being decoded, then head->done is set to -1 to indicate that there will be
824
no gzip header information forthcoming. Note that Z_BLOCK can be used to
825
force inflate() to return immediately after header processing is complete
826
and before any actual data is decompressed.
827
828
The text, time, xflags, and os fields are filled in with the gzip header
829
contents. hcrc is set to true if there is a header CRC. (The header CRC
830
was valid if done is set to one.) If extra is not Z_NULL, then extra_max
831
contains the maximum number of bytes to write to extra. Once done is true,
832
extra_len contains the actual extra field length, and extra contains the
833
extra field, or that field truncated if extra_max is less than extra_len.
834
If name is not Z_NULL, then up to name_max characters are written there,
835
terminated with a zero unless the length is greater than name_max. If
836
comment is not Z_NULL, then up to comm_max characters are written there,
837
terminated with a zero unless the length is greater than comm_max. When
838
any of extra, name, or comment are not Z_NULL and the respective field is
839
not present in the header, then that field is set to Z_NULL to signal its
840
absence. This allows the use of deflateSetHeader() with the returned
841
structure to duplicate the header. However if those fields are set to
842
allocated memory, then the application will need to save those pointers
843
elsewhere so that they can be eventually freed.
844
845
If inflateGetHeader is not used, then the header information is simply
846
discarded. The header is always checked for validity, including the header
847
CRC if present. inflateReset() will reset the process to discard the header
848
information. The application would need to call inflateGetHeader() again to
849
retrieve the header from the next gzip stream.
850
851
inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
852
stream state was inconsistent.
853
*/
854
855
/*
856
ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
857
unsigned char FAR *window));
858
859
Initialize the internal stream state for decompression using inflateBack()
860
calls. The fields zalloc, zfree and opaque in strm must be initialized
861
before the call. If zalloc and zfree are Z_NULL, then the default library-
862
derived memory allocation routines are used. windowBits is the base two
863
logarithm of the window size, in the range 8..15. window is a caller
864
supplied buffer of that size. Except for special applications where it is
865
assured that deflate was used with small window sizes, windowBits must be 15
866
and a 32K byte window must be supplied to be able to decompress general
867
deflate streams.
868
869
See inflateBack() for the usage of these routines.
870
871
inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
872
the paramaters are invalid, Z_MEM_ERROR if the internal state could not
873
be allocated, or Z_VERSION_ERROR if the version of the library does not
874
match the version of the header file.
875
*/
876
877
typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
878
typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
879
880
ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
881
in_func in, void FAR *in_desc,
882
out_func out, void FAR *out_desc));
883
/*
884
inflateBack() does a raw inflate with a single call using a call-back
885
interface for input and output. This is more efficient than inflate() for
886
file i/o applications in that it avoids copying between the output and the
887
sliding window by simply making the window itself the output buffer. This
888
function trusts the application to not change the output buffer passed by
889
the output function, at least until inflateBack() returns.
890
891
inflateBackInit() must be called first to allocate the internal state
892
and to initialize the state with the user-provided window buffer.
893
inflateBack() may then be used multiple times to inflate a complete, raw
894
deflate stream with each call. inflateBackEnd() is then called to free
895
the allocated state.
896
897
A raw deflate stream is one with no zlib or gzip header or trailer.
898
This routine would normally be used in a utility that reads zip or gzip
899
files and writes out uncompressed files. The utility would decode the
900
header and process the trailer on its own, hence this routine expects
901
only the raw deflate stream to decompress. This is different from the
902
normal behavior of inflate(), which expects either a zlib or gzip header and
903
trailer around the deflate stream.
904
905
inflateBack() uses two subroutines supplied by the caller that are then
906
called by inflateBack() for input and output. inflateBack() calls those
907
routines until it reads a complete deflate stream and writes out all of the
908
uncompressed data, or until it encounters an error. The function's
909
parameters and return types are defined above in the in_func and out_func
910
typedefs. inflateBack() will call in(in_desc, &buf) which should return the
911
number of bytes of provided input, and a pointer to that input in buf. If
912
there is no input available, in() must return zero--buf is ignored in that
913
case--and inflateBack() will return a buffer error. inflateBack() will call
914
out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
915
should return zero on success, or non-zero on failure. If out() returns
916
non-zero, inflateBack() will return with an error. Neither in() nor out()
917
are permitted to change the contents of the window provided to
918
inflateBackInit(), which is also the buffer that out() uses to write from.
919
The length written by out() will be at most the window size. Any non-zero
920
amount of input may be provided by in().
921
922
For convenience, inflateBack() can be provided input on the first call by
923
setting strm->next_in and strm->avail_in. If that input is exhausted, then
924
in() will be called. Therefore strm->next_in must be initialized before
925
calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
926
immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
927
must also be initialized, and then if strm->avail_in is not zero, input will
928
initially be taken from strm->next_in[0 .. strm->avail_in - 1].
929
930
The in_desc and out_desc parameters of inflateBack() is passed as the
931
first parameter of in() and out() respectively when they are called. These
932
descriptors can be optionally used to pass any information that the caller-
933
supplied in() and out() functions need to do their job.
934
935
On return, inflateBack() will set strm->next_in and strm->avail_in to
936
pass back any unused input that was provided by the last in() call. The
937
return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
938
if in() or out() returned an error, Z_DATA_ERROR if there was a format
939
error in the deflate stream (in which case strm->msg is set to indicate the
940
nature of the error), or Z_STREAM_ERROR if the stream was not properly
941
initialized. In the case of Z_BUF_ERROR, an input or output error can be
942
distinguished using strm->next_in which will be Z_NULL only if in() returned
943
an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
944
out() returning non-zero. (in() will always be called before out(), so
945
strm->next_in is assured to be defined if out() returns non-zero.) Note
946
that inflateBack() cannot return Z_OK.
947
*/
948
949
ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
950
/*
951
All memory allocated by inflateBackInit() is freed.
952
953
inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
954
state was inconsistent.
955
*/
956
957
ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
958
/* Return flags indicating compile-time options.
959
960
Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
961
1.0: size of uInt
962
3.2: size of uLong
963
5.4: size of voidpf (pointer)
964
7.6: size of z_off_t
965
966
Compiler, assembler, and debug options:
967
8: DEBUG
968
9: ASMV or ASMINF -- use ASM code
969
10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
970
11: 0 (reserved)
971
972
One-time table building (smaller code, but not thread-safe if true):
973
12: BUILDFIXED -- build static block decoding tables when needed
974
13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
975
14,15: 0 (reserved)
976
977
Library content (indicates missing functionality):
978
16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
979
deflate code when not needed)
980
17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
981
and decode gzip streams (to avoid linking crc code)
982
18-19: 0 (reserved)
983
984
Operation variations (changes in library functionality):
985
20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
986
21: FASTEST -- deflate algorithm with only one, lowest compression level
987
22,23: 0 (reserved)
988
989
The sprintf variant used by gzprintf (zero is best):
990
24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
991
25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
992
26: 0 = returns value, 1 = void -- 1 means inferred string length returned
993
994
Remainder:
995
27-31: 0 (reserved)
996
*/
997
998
999
/* utility functions */
1000
1001
/*
1002
The following utility functions are implemented on top of the
1003
basic stream-oriented functions. To simplify the interface, some
1004
default options are assumed (compression level and memory usage,
1005
standard memory allocation functions). The source code of these
1006
utility functions can easily be modified if you need special options.
1007
*/
1008
1009
ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
1010
const Bytef *source, uLong sourceLen));
1011
/*
1012
Compresses the source buffer into the destination buffer. sourceLen is
1013
the byte length of the source buffer. Upon entry, destLen is the total
1014
size of the destination buffer, which must be at least the value returned
1015
by compressBound(sourceLen). Upon exit, destLen is the actual size of the
1016
compressed buffer.
1017
This function can be used to compress a whole file at once if the
1018
input file is mmap'ed.
1019
compress returns Z_OK if success, Z_MEM_ERROR if there was not
1020
enough memory, Z_BUF_ERROR if there was not enough room in the output
1021
buffer.
1022
*/
1023
1024
ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
1025
const Bytef *source, uLong sourceLen,
1026
int level));
1027
/*
1028
Compresses the source buffer into the destination buffer. The level
1029
parameter has the same meaning as in deflateInit. sourceLen is the byte
1030
length of the source buffer. Upon entry, destLen is the total size of the
1031
destination buffer, which must be at least the value returned by
1032
compressBound(sourceLen). Upon exit, destLen is the actual size of the
1033
compressed buffer.
1034
1035
compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
1036
memory, Z_BUF_ERROR if there was not enough room in the output buffer,
1037
Z_STREAM_ERROR if the level parameter is invalid.
1038
*/
1039
1040
ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
1041
/*
1042
compressBound() returns an upper bound on the compressed size after
1043
compress() or compress2() on sourceLen bytes. It would be used before
1044
a compress() or compress2() call to allocate the destination buffer.
1045
*/
1046
1047
ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
1048
const Bytef *source, uLong sourceLen));
1049
/*
1050
Decompresses the source buffer into the destination buffer. sourceLen is
1051
the byte length of the source buffer. Upon entry, destLen is the total
1052
size of the destination buffer, which must be large enough to hold the
1053
entire uncompressed data. (The size of the uncompressed data must have
1054
been saved previously by the compressor and transmitted to the decompressor
1055
by some mechanism outside the scope of this compression library.)
1056
Upon exit, destLen is the actual size of the compressed buffer.
1057
This function can be used to decompress a whole file at once if the
1058
input file is mmap'ed.
1059
1060
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
1061
enough memory, Z_BUF_ERROR if there was not enough room in the output
1062
buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
1063
*/
1064
1065
1066
typedef voidp gzFile;
1067
1068
ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
1069
/*
1070
Opens a gzip (.gz) file for reading or writing. The mode parameter
1071
is as in fopen ("rb" or "wb") but can also include a compression level
1072
("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
1073
Huffman only compression as in "wb1h", or 'R' for run-length encoding
1074
as in "wb1R". (See the description of deflateInit2 for more information
1075
about the strategy parameter.)
1076
1077
gzopen can be used to read a file which is not in gzip format; in this
1078
case gzread will directly read from the file without decompression.
1079
1080
gzopen returns NULL if the file could not be opened or if there was
1081
insufficient memory to allocate the (de)compression state; errno
1082
can be checked to distinguish the two cases (if errno is zero, the
1083
zlib error is Z_MEM_ERROR). */
1084
1085
ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
1086
/*
1087
gzdopen() associates a gzFile with the file descriptor fd. File
1088
descriptors are obtained from calls like open, dup, creat, pipe or
1089
fileno (in the file has been previously opened with fopen).
1090
The mode parameter is as in gzopen.
1091
The next call of gzclose on the returned gzFile will also close the
1092
file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
1093
descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
1094
gzdopen returns NULL if there was insufficient memory to allocate
1095
the (de)compression state.
1096
*/
1097
1098
ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
1099
/*
1100
Dynamically update the compression level or strategy. See the description
1101
of deflateInit2 for the meaning of these parameters.
1102
gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
1103
opened for writing.
1104
*/
1105
1106
ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
1107
/*
1108
Reads the given number of uncompressed bytes from the compressed file.
1109
If the input file was not in gzip format, gzread copies the given number
1110
of bytes into the buffer.
1111
gzread returns the number of uncompressed bytes actually read (0 for
1112
end of file, -1 for error). */
1113
1114
ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
1115
voidpc buf, unsigned len));
1116
/*
1117
Writes the given number of uncompressed bytes into the compressed file.
1118
gzwrite returns the number of uncompressed bytes actually written
1119
(0 in case of error).
1120
*/
1121
1122
ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
1123
/*
1124
Converts, formats, and writes the args to the compressed file under
1125
control of the format string, as in fprintf. gzprintf returns the number of
1126
uncompressed bytes actually written (0 in case of error). The number of
1127
uncompressed bytes written is limited to 4095. The caller should assure that
1128
this limit is not exceeded. If it is exceeded, then gzprintf() will return
1129
return an error (0) with nothing written. In this case, there may also be a
1130
buffer overflow with unpredictable consequences, which is possible only if
1131
zlib was compiled with the insecure functions sprintf() or vsprintf()
1132
because the secure snprintf() or vsnprintf() functions were not available.
1133
*/
1134
1135
ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
1136
/*
1137
Writes the given null-terminated string to the compressed file, excluding
1138
the terminating null character.
1139
gzputs returns the number of characters written, or -1 in case of error.
1140
*/
1141
1142
ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
1143
/*
1144
Reads bytes from the compressed file until len-1 characters are read, or
1145
a newline character is read and transferred to buf, or an end-of-file
1146
condition is encountered. The string is then terminated with a null
1147
character.
1148
gzgets returns buf, or Z_NULL in case of error.
1149
*/
1150
1151
ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
1152
/*
1153
Writes c, converted to an unsigned char, into the compressed file.
1154
gzputc returns the value that was written, or -1 in case of error.
1155
*/
1156
1157
ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
1158
/*
1159
Reads one byte from the compressed file. gzgetc returns this byte
1160
or -1 in case of end of file or error.
1161
*/
1162
1163
ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
1164
/*
1165
Push one character back onto the stream to be read again later.
1166
Only one character of push-back is allowed. gzungetc() returns the
1167
character pushed, or -1 on failure. gzungetc() will fail if a
1168
character has been pushed but not read yet, or if c is -1. The pushed
1169
character will be discarded if the stream is repositioned with gzseek()
1170
or gzrewind().
1171
*/
1172
1173
ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
1174
/*
1175
Flushes all pending output into the compressed file. The parameter
1176
flush is as in the deflate() function. The return value is the zlib
1177
error number (see function gzerror below). gzflush returns Z_OK if
1178
the flush parameter is Z_FINISH and all output could be flushed.
1179
gzflush should be called only when strictly necessary because it can
1180
degrade compression.
1181
*/
1182
1183
ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
1184
z_off_t offset, int whence));
1185
/*
1186
Sets the starting position for the next gzread or gzwrite on the
1187
given compressed file. The offset represents a number of bytes in the
1188
uncompressed data stream. The whence parameter is defined as in lseek(2);
1189
the value SEEK_END is not supported.
1190
If the file is opened for reading, this function is emulated but can be
1191
extremely slow. If the file is opened for writing, only forward seeks are
1192
supported; gzseek then compresses a sequence of zeroes up to the new
1193
starting position.
1194
1195
gzseek returns the resulting offset location as measured in bytes from
1196
the beginning of the uncompressed stream, or -1 in case of error, in
1197
particular if the file is opened for writing and the new starting position
1198
would be before the current position.
1199
*/
1200
1201
ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
1202
/*
1203
Rewinds the given file. This function is supported only for reading.
1204
1205
gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
1206
*/
1207
1208
ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
1209
/*
1210
Returns the starting position for the next gzread or gzwrite on the
1211
given compressed file. This position represents a number of bytes in the
1212
uncompressed data stream.
1213
1214
gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
1215
*/
1216
1217
ZEXTERN int ZEXPORT gzeof OF((gzFile file));
1218
/*
1219
Returns 1 when EOF has previously been detected reading the given
1220
input stream, otherwise zero.
1221
*/
1222
1223
ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
1224
/*
1225
Returns 1 if file is being read directly without decompression, otherwise
1226
zero.
1227
*/
1228
1229
ZEXTERN int ZEXPORT gzclose OF((gzFile file));
1230
/*
1231
Flushes all pending output if necessary, closes the compressed file
1232
and deallocates all the (de)compression state. The return value is the zlib
1233
error number (see function gzerror below).
1234
*/
1235
1236
ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
1237
/*
1238
Returns the error message for the last error which occurred on the
1239
given compressed file. errnum is set to zlib error number. If an
1240
error occurred in the file system and not in the compression library,
1241
errnum is set to Z_ERRNO and the application may consult errno
1242
to get the exact error code.
1243
*/
1244
1245
ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
1246
/*
1247
Clears the error and end-of-file flags for file. This is analogous to the
1248
clearerr() function in stdio. This is useful for continuing to read a gzip
1249
file that is being written concurrently.
1250
*/
1251
1252
/* checksum functions */
1253
1254
/*
1255
These functions are not related to compression but are exported
1256
anyway because they might be useful in applications using the
1257
compression library.
1258
*/
1259
1260
ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
1261
/*
1262
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1263
return the updated checksum. If buf is NULL, this function returns
1264
the required initial value for the checksum.
1265
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
1266
much faster. Usage example:
1267
1268
uLong adler = adler32(0L, Z_NULL, 0);
1269
1270
while (read_buffer(buffer, length) != EOF) {
1271
adler = adler32(adler, buffer, length);
1272
}
1273
if (adler != original_adler) error();
1274
*/
1275
1276
ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
1277
z_off_t len2));
1278
/*
1279
Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1280
and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1281
each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1282
seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
1283
*/
1284
1285
ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
1286
/*
1287
Update a running CRC-32 with the bytes buf[0..len-1] and return the
1288
updated CRC-32. If buf is NULL, this function returns the required initial
1289
value for the for the crc. Pre- and post-conditioning (one's complement) is
1290
performed within this function so it shouldn't be done by the application.
1291
Usage example:
1292
1293
uLong crc = crc32(0L, Z_NULL, 0);
1294
1295
while (read_buffer(buffer, length) != EOF) {
1296
crc = crc32(crc, buffer, length);
1297
}
1298
if (crc != original_crc) error();
1299
*/
1300
1301
ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
1302
1303
/*
1304
Combine two CRC-32 check values into one. For two sequences of bytes,
1305
seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1306
calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1307
check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
1308
len2.
1309
*/
1310
1311
1312
/* various hacks, don't look :) */
1313
1314
/* deflateInit and inflateInit are macros to allow checking the zlib version
1315
* and the compiler's view of z_stream:
1316
*/
1317
ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
1318
const char *version, int stream_size));
1319
ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
1320
const char *version, int stream_size));
1321
ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
1322
int windowBits, int memLevel,
1323
int strategy, const char *version,
1324
int stream_size));
1325
ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
1326
const char *version, int stream_size));
1327
ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
1328
unsigned char FAR *window,
1329
const char *version,
1330
int stream_size));
1331
#define deflateInit(strm, level) \
1332
deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
1333
#define inflateInit(strm) \
1334
inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
1335
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
1336
deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
1337
(strategy), ZLIB_VERSION, sizeof(z_stream))
1338
#define inflateInit2(strm, windowBits) \
1339
inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
1340
#define inflateBackInit(strm, windowBits, window) \
1341
inflateBackInit_((strm), (windowBits), (window), \
1342
ZLIB_VERSION, sizeof(z_stream))
1343
1344
1345
#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
1346
struct internal_state {int dummy;}; /* hack for buggy compilers */
1347
#endif
1348
1349
ZEXTERN const char * ZEXPORT zError OF((int));
1350
ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
1351
ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
1352
1353
#ifdef __cplusplus
1354
}
1355
#endif
1356
1357
#endif /* ZLIB_H */
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