| 1 | /* zlib.h -- interface of the 'zlib' general purpose compression library
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| 2 | version 1.2.2, October 3rd, 2004
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| 3 |
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| 4 | Copyright (C) 1995-2004 Jean-loup Gailly and Mark Adler
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| 5 |
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| 6 | This software is provided 'as-is', without any express or implied
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| 7 | warranty. In no event will the authors be held liable for any damages
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| 8 | arising from the use of this software.
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| 9 |
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| 10 | Permission is granted to anyone to use this software for any purpose,
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| 11 | including commercial applications, and to alter it and redistribute it
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| 12 | freely, subject to the following restrictions:
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| 13 |
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| 14 | 1. The origin of this software must not be misrepresented; you must not
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| 15 | claim that you wrote the original software. If you use this software
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| 16 | in a product, an acknowledgment in the product documentation would be
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| 17 | appreciated but is not required.
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| 18 | 2. Altered source versions must be plainly marked as such, and must not be
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| 19 | misrepresented as being the original software.
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| 20 | 3. This notice may not be removed or altered from any source distribution.
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| 21 |
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| 22 | Jean-loup Gailly Mark Adler
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| 23 | jloup@gzip.org madler@alumni.caltech.edu
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| 24 |
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| 25 |
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| 26 | The data format used by the zlib library is described by RFCs (Request for
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| 27 | Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
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| 28 | (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
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| 29 | */
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| 30 |
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| 31 | #ifndef _ZLIB_H
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| 32 | #define _ZLIB_H
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| 33 |
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| 34 | #include "zconf.h"
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| 35 |
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| 36 | #ifdef __cplusplus
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| 37 | extern "C" {
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| 38 | #endif
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| 39 |
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| 40 | #define ZLIB_VERSION "1.2.2"
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| 41 | #define ZLIB_VERNUM 0x1220
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| 42 |
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| 43 | /*
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| 44 | The 'zlib' compression library provides in-memory compression and
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| 45 | decompression functions, including integrity checks of the uncompressed
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| 46 | data. This version of the library supports only one compression method
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| 47 | (deflation) but other algorithms will be added later and will have the same
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| 48 | stream interface.
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| 49 |
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| 50 | Compression can be done in a single step if the buffers are large
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| 51 | enough (for example if an input file is mmap'ed), or can be done by
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| 52 | repeated calls of the compression function. In the latter case, the
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| 53 | application must provide more input and/or consume the output
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| 54 | (providing more output space) before each call.
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| 55 |
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| 56 | The compressed data format used by default by the in-memory functions is
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| 57 | the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
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| 58 | around a deflate stream, which is itself documented in RFC 1951.
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| 59 |
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| 60 | The library also supports reading and writing files in gzip (.gz) format
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| 61 | with an interface similar to that of stdio using the functions that start
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| 62 | with "gz". The gzip format is different from the zlib format. gzip is a
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| 63 | gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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| 64 |
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| 65 | This library can optionally read and write gzip streams in memory as well.
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| 66 |
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| 67 | The zlib format was designed to be compact and fast for use in memory
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| 68 | and on communications channels. The gzip format was designed for single-
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| 69 | file compression on file systems, has a larger header than zlib to maintain
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| 70 | directory information, and uses a different, slower check method than zlib.
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| 71 |
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| 72 | The library does not install any signal handler. The decoder checks
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| 73 | the consistency of the compressed data, so the library should never
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| 74 | crash even in case of corrupted input.
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| 75 | */
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| 76 |
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| 77 | typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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| 78 | typedef void (*free_func) OF((voidpf opaque, voidpf address));
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| 79 |
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| 80 | struct internal_state;
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| 81 |
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| 82 | typedef struct z_stream_s {
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| 83 | Bytef *next_in; /* next input byte */
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| 84 | uInt avail_in; /* number of bytes available at next_in */
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| 85 | uLong total_in; /* total nb of input bytes read so far */
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| 86 |
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| 87 | Bytef *next_out; /* next output byte should be put there */
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| 88 | uInt avail_out; /* remaining free space at next_out */
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| 89 | uLong total_out; /* total nb of bytes output so far */
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| 90 |
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| 91 | char *msg; /* last error message, NULL if no error */
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| 92 | struct internal_state FAR *state; /* not visible by applications */
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| 93 |
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| 94 | alloc_func zalloc; /* used to allocate the internal state */
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| 95 | free_func zfree; /* used to free the internal state */
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| 96 | voidpf opaque; /* private data object passed to zalloc and zfree */
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| 97 |
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| 98 | int data_type; /* best guess about the data type: ascii or binary */
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| 99 | uLong adler; /* adler32 value of the uncompressed data */
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| 100 | uLong reserved; /* reserved for future use */
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| 101 | } z_stream;
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| 102 |
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| 103 | typedef z_stream FAR *z_streamp;
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| 104 |
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| 105 | /*
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| 106 | The application must update next_in and avail_in when avail_in has
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| 107 | dropped to zero. It must update next_out and avail_out when avail_out
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| 108 | has dropped to zero. The application must initialize zalloc, zfree and
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| 109 | opaque before calling the init function. All other fields are set by the
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| 110 | compression library and must not be updated by the application.
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| 111 |
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| 112 | The opaque value provided by the application will be passed as the first
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| 113 | parameter for calls of zalloc and zfree. This can be useful for custom
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| 114 | memory management. The compression library attaches no meaning to the
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| 115 | opaque value.
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| 116 |
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| 117 | zalloc must return Z_NULL if there is not enough memory for the object.
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| 118 | If zlib is used in a multi-threaded application, zalloc and zfree must be
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| 119 | thread safe.
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| 120 |
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| 121 | On 16-bit systems, the functions zalloc and zfree must be able to allocate
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| 122 | exactly 65536 bytes, but will not be required to allocate more than this
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| 123 | if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
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| 124 | pointers returned by zalloc for objects of exactly 65536 bytes *must*
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| 125 | have their offset normalized to zero. The default allocation function
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| 126 | provided by this library ensures this (see zutil.c). To reduce memory
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| 127 | requirements and avoid any allocation of 64K objects, at the expense of
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| 128 | compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
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| 129 |
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| 130 | The fields total_in and total_out can be used for statistics or
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| 131 | progress reports. After compression, total_in holds the total size of
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| 132 | the uncompressed data and may be saved for use in the decompressor
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| 133 | (particularly if the decompressor wants to decompress everything in
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| 134 | a single step).
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| 135 | */
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| 136 |
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| 137 | /* constants */
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| 138 |
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| 139 | #define Z_NO_FLUSH 0
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| 140 | #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
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| 141 | #define Z_SYNC_FLUSH 2
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| 142 | #define Z_FULL_FLUSH 3
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| 143 | #define Z_FINISH 4
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| 144 | #define Z_BLOCK 5
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| 145 | /* Allowed flush values; see deflate() and inflate() below for details */
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| 146 |
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| 147 | #define Z_OK 0
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| 148 | #define Z_STREAM_END 1
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| 149 | #define Z_NEED_DICT 2
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| 150 | #define Z_ERRNO (-1)
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| 151 | #define Z_STREAM_ERROR (-2)
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| 152 | #define Z_DATA_ERROR (-3)
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| 153 | #define Z_MEM_ERROR (-4)
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| 154 | #define Z_BUF_ERROR (-5)
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| 155 | #define Z_VERSION_ERROR (-6)
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| 156 | /* Return codes for the compression/decompression functions. Negative
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| 157 | * values are errors, positive values are used for special but normal events.
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| 158 | */
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| 159 |
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| 160 | #define Z_NO_COMPRESSION 0
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| 161 | #define Z_BEST_SPEED 1
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| 162 | #define Z_BEST_COMPRESSION 9
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| 163 | #define Z_DEFAULT_COMPRESSION (-1)
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| 164 | /* compression levels */
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| 165 |
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| 166 | #define Z_FILTERED 1
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| 167 | #define Z_HUFFMAN_ONLY 2
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| 168 | #define Z_RLE 3
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| 169 | #define Z_DEFAULT_STRATEGY 0
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| 170 | /* compression strategy; see deflateInit2() below for details */
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| 171 |
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| 172 | #define Z_BINARY 0
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| 173 | #define Z_ASCII 1
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| 174 | #define Z_UNKNOWN 2
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| 175 | /* Possible values of the data_type field (though see inflate()) */
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| 176 |
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| 177 | #define Z_DEFLATED 8
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| 178 | /* The deflate compression method (the only one supported in this version) */
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| 179 |
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| 180 | #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
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| 181 |
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| 182 | #define zlib_version zlibVersion()
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| 183 | /* for compatibility with versions < 1.0.2 */
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| 184 |
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| 185 | /* basic functions */
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| 186 |
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| 187 | ZEXTERN const char * ZEXPORT zlibVersion OF((void));
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| 188 | /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
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| 189 | If the first character differs, the library code actually used is
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| 190 | not compatible with the zlib.h header file used by the application.
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| 191 | This check is automatically made by deflateInit and inflateInit.
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| 192 | */
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| 193 |
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| 194 | /*
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| 195 | ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
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| 196 |
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| 197 | Initializes the internal stream state for compression. The fields
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| 198 | zalloc, zfree and opaque must be initialized before by the caller.
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| 199 | If zalloc and zfree are set to Z_NULL, deflateInit updates them to
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| 200 | use default allocation functions.
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| 201 |
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| 202 | The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
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| 203 | 1 gives best speed, 9 gives best compression, 0 gives no compression at
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| 204 | all (the input data is simply copied a block at a time).
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| 205 | Z_DEFAULT_COMPRESSION requests a default compromise between speed and
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| 206 | compression (currently equivalent to level 6).
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| 207 |
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| 208 | deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
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| 209 | enough memory, Z_STREAM_ERROR if level is not a valid compression level,
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| 210 | Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
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| 211 | with the version assumed by the caller (ZLIB_VERSION).
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| 212 | msg is set to null if there is no error message. deflateInit does not
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| 213 | perform any compression: this will be done by deflate().
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| 214 | */
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| 215 |
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| 216 |
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| 217 | ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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| 218 | /*
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| 219 | deflate compresses as much data as possible, and stops when the input
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| 220 | buffer becomes empty or the output buffer becomes full. It may introduce some
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| 221 | output latency (reading input without producing any output) except when
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| 222 | forced to flush.
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| 223 |
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| 224 | The detailed semantics are as follows. deflate performs one or both of the
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| 225 | following actions:
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| 226 |
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| 227 | - Compress more input starting at next_in and update next_in and avail_in
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| 228 | accordingly. If not all input can be processed (because there is not
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| 229 | enough room in the output buffer), next_in and avail_in are updated and
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| 230 | processing will resume at this point for the next call of deflate().
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| 231 |
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| 232 | - Provide more output starting at next_out and update next_out and avail_out
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| 233 | accordingly. This action is forced if the parameter flush is non zero.
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| 234 | Forcing flush frequently degrades the compression ratio, so this parameter
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| 235 | should be set only when necessary (in interactive applications).
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| 236 | Some output may be provided even if flush is not set.
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| 237 |
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| 238 | Before the call of deflate(), the application should ensure that at least
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| 239 | one of the actions is possible, by providing more input and/or consuming
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| 240 | more output, and updating avail_in or avail_out accordingly; avail_out
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| 241 | should never be zero before the call. The application can consume the
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| 242 | compressed output when it wants, for example when the output buffer is full
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| 243 | (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
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| 244 | and with zero avail_out, it must be called again after making room in the
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| 245 | output buffer because there might be more output pending.
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| 246 |
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| 247 | If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
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| 248 | flushed to the output buffer and the output is aligned on a byte boundary, so
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| 249 | that the decompressor can get all input data available so far. (In particular
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| 250 | avail_in is zero after the call if enough output space has been provided
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| 251 | before the call.) Flushing may degrade compression for some compression
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| 252 | algorithms and so it should be used only when necessary.
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| 253 |
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| 254 | If flush is set to Z_FULL_FLUSH, all output is flushed as with
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| 255 | Z_SYNC_FLUSH, and the compression state is reset so that decompression can
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| 256 | restart from this point if previous compressed data has been damaged or if
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| 257 | random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
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| 258 | the compression.
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| 259 |
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| 260 | If deflate returns with avail_out == 0, this function must be called again
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| 261 | with the same value of the flush parameter and more output space (updated
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| 262 | avail_out), until the flush is complete (deflate returns with non-zero
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| 263 | avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
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| 264 | avail_out is greater than six to avoid repeated flush markers due to
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| 265 | avail_out == 0 on return.
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| 266 |
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| 267 | If the parameter flush is set to Z_FINISH, pending input is processed,
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| 268 | pending output is flushed and deflate returns with Z_STREAM_END if there
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| 269 | was enough output space; if deflate returns with Z_OK, this function must be
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| 270 | called again with Z_FINISH and more output space (updated avail_out) but no
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| 271 | more input data, until it returns with Z_STREAM_END or an error. After
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| 272 | deflate has returned Z_STREAM_END, the only possible operations on the
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| 273 | stream are deflateReset or deflateEnd.
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| 274 |
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| 275 | Z_FINISH can be used immediately after deflateInit if all the compression
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| 276 | is to be done in a single step. In this case, avail_out must be at least
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| 277 | the value returned by deflateBound (see below). If deflate does not return
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| 278 | Z_STREAM_END, then it must be called again as described above.
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| 279 |
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| 280 | deflate() sets strm->adler to the adler32 checksum of all input read
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| 281 | so far (that is, total_in bytes).
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| 282 |
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| 283 | deflate() may update data_type if it can make a good guess about
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| 284 | the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
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| 285 | binary. This field is only for information purposes and does not affect
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| 286 | the compression algorithm in any manner.
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| 287 |
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| 288 | deflate() returns Z_OK if some progress has been made (more input
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| 289 | processed or more output produced), Z_STREAM_END if all input has been
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| 290 | consumed and all output has been produced (only when flush is set to
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| 291 | Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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| 292 | if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
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| 293 | (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
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| 294 | fatal, and deflate() can be called again with more input and more output
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| 295 | space to continue compressing.
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| 296 | */
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| 297 |
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| 298 |
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| 299 | ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
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| 300 | /*
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| 301 | All dynamically allocated data structures for this stream are freed.
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| 302 | This function discards any unprocessed input and does not flush any
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| 303 | pending output.
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| 304 |
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| 305 | deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
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| 306 | stream state was inconsistent, Z_DATA_ERROR if the stream was freed
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| 307 | prematurely (some input or output was discarded). In the error case,
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| 308 | msg may be set but then points to a static string (which must not be
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| 309 | deallocated).
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| 310 | */
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| 311 |
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| 312 |
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| 313 | /*
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| 314 | ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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| 315 |
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| 316 | Initializes the internal stream state for decompression. The fields
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| 317 | next_in, avail_in, zalloc, zfree and opaque must be initialized before by
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| 318 | the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
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| 319 | value depends on the compression method), inflateInit determines the
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| 320 | compression method from the zlib header and allocates all data structures
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| 321 | accordingly; otherwise the allocation will be deferred to the first call of
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| 322 | inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
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| 323 | use default allocation functions.
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| 324 |
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| 325 | inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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| 326 | memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
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| 327 | version assumed by the caller. msg is set to null if there is no error
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| 328 | message. inflateInit does not perform any decompression apart from reading
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| 329 | the zlib header if present: this will be done by inflate(). (So next_in and
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| 330 | avail_in may be modified, but next_out and avail_out are unchanged.)
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| 331 | */
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| 332 |
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| 333 |
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| 334 | ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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| 335 | /*
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| 336 | inflate decompresses as much data as possible, and stops when the input
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| 337 | buffer becomes empty or the output buffer becomes full. It may introduce
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| 338 | some output latency (reading input without producing any output) except when
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| 339 | forced to flush.
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| 340 |
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| 341 | The detailed semantics are as follows. inflate performs one or both of the
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| 342 | following actions:
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| 343 |
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| 344 | - Decompress more input starting at next_in and update next_in and avail_in
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| 345 | accordingly. If not all input can be processed (because there is not
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| 346 | enough room in the output buffer), next_in is updated and processing
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| 347 | will resume at this point for the next call of inflate().
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| 348 |
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| 349 | - Provide more output starting at next_out and update next_out and avail_out
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| 350 | accordingly. inflate() provides as much output as possible, until there
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| 351 | is no more input data or no more space in the output buffer (see below
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| 352 | about the flush parameter).
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| 353 |
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| 354 | Before the call of inflate(), the application should ensure that at least
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| 355 | one of the actions is possible, by providing more input and/or consuming
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| 356 | more output, and updating the next_* and avail_* values accordingly.
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| 357 | The application can consume the uncompressed output when it wants, for
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| 358 | example when the output buffer is full (avail_out == 0), or after each
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| 359 | call of inflate(). If inflate returns Z_OK and with zero avail_out, it
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| 360 | must be called again after making room in the output buffer because there
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| 361 | might be more output pending.
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| 362 |
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| 363 | The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
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| 364 | Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
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| 365 | output as possible to the output buffer. Z_BLOCK requests that inflate() stop
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| 366 | if and when it get to the next deflate block boundary. When decoding the zlib
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|---|
| 367 | or gzip format, this will cause inflate() to return immediately after the
|
|---|
| 368 | header and before the first block. When doing a raw inflate, inflate() will
|
|---|
| 369 | go ahead and process the first block, and will return when it gets to the end
|
|---|
| 370 | of that block, or when it runs out of data.
|
|---|
| 371 |
|
|---|
| 372 | The Z_BLOCK option assists in appending to or combining deflate streams.
|
|---|
| 373 | Also to assist in this, on return inflate() will set strm->data_type to the
|
|---|
| 374 | number of unused bits in the last byte taken from strm->next_in, plus 64
|
|---|
| 375 | if inflate() is currently decoding the last block in the deflate stream,
|
|---|
| 376 | plus 128 if inflate() returned immediately after decoding an end-of-block
|
|---|
| 377 | code or decoding the complete header up to just before the first byte of the
|
|---|
| 378 | deflate stream. The end-of-block will not be indicated until all of the
|
|---|
| 379 | uncompressed data from that block has been written to strm->next_out. The
|
|---|
| 380 | number of unused bits may in general be greater than seven, except when
|
|---|
| 381 | bit 7 of data_type is set, in which case the number of unused bits will be
|
|---|
| 382 | less than eight.
|
|---|
| 383 |
|
|---|
| 384 | inflate() should normally be called until it returns Z_STREAM_END or an
|
|---|
| 385 | error. However if all decompression is to be performed in a single step
|
|---|
| 386 | (a single call of inflate), the parameter flush should be set to
|
|---|
| 387 | Z_FINISH. In this case all pending input is processed and all pending
|
|---|
| 388 | output is flushed; avail_out must be large enough to hold all the
|
|---|
| 389 | uncompressed data. (The size of the uncompressed data may have been saved
|
|---|
| 390 | by the compressor for this purpose.) The next operation on this stream must
|
|---|
| 391 | be inflateEnd to deallocate the decompression state. The use of Z_FINISH
|
|---|
| 392 | is never required, but can be used to inform inflate that a faster approach
|
|---|
| 393 | may be used for the single inflate() call.
|
|---|
| 394 |
|
|---|
| 395 | In this implementation, inflate() always flushes as much output as
|
|---|
| 396 | possible to the output buffer, and always uses the faster approach on the
|
|---|
| 397 | first call. So the only effect of the flush parameter in this implementation
|
|---|
| 398 | is on the return value of inflate(), as noted below, or when it returns early
|
|---|
| 399 | because Z_BLOCK is used.
|
|---|
| 400 |
|
|---|
| 401 | If a preset dictionary is needed after this call (see inflateSetDictionary
|
|---|
| 402 | below), inflate sets strm->adler to the adler32 checksum of the dictionary
|
|---|
| 403 | chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
|
|---|
| 404 | strm->adler to the adler32 checksum of all output produced so far (that is,
|
|---|
| 405 | total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
|
|---|
| 406 | below. At the end of the stream, inflate() checks that its computed adler32
|
|---|
| 407 | checksum is equal to that saved by the compressor and returns Z_STREAM_END
|
|---|
| 408 | only if the checksum is correct.
|
|---|
| 409 |
|
|---|
| 410 | inflate() will decompress and check either zlib-wrapped or gzip-wrapped
|
|---|
| 411 | deflate data. The header type is detected automatically. Any information
|
|---|
| 412 | contained in the gzip header is not retained, so applications that need that
|
|---|
| 413 | information should instead use raw inflate, see inflateInit2() below, or
|
|---|
| 414 | inflateBack() and perform their own processing of the gzip header and
|
|---|
| 415 | trailer.
|
|---|
| 416 |
|
|---|
| 417 | inflate() returns Z_OK if some progress has been made (more input processed
|
|---|
| 418 | or more output produced), Z_STREAM_END if the end of the compressed data has
|
|---|
| 419 | been reached and all uncompressed output has been produced, Z_NEED_DICT if a
|
|---|
| 420 | preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
|
|---|
| 421 | corrupted (input stream not conforming to the zlib format or incorrect check
|
|---|
| 422 | value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
|
|---|
| 423 | if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
|
|---|
| 424 | Z_BUF_ERROR if no progress is possible or if there was not enough room in the
|
|---|
| 425 | output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
|
|---|
| 426 | inflate() can be called again with more input and more output space to
|
|---|
| 427 | continue decompressing. If Z_DATA_ERROR is returned, the application may then
|
|---|
| 428 | call inflateSync() to look for a good compression block if a partial recovery
|
|---|
| 429 | of the data is desired.
|
|---|
| 430 | */
|
|---|
| 431 |
|
|---|
| 432 |
|
|---|
| 433 | ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
|
|---|
| 434 | /*
|
|---|
| 435 | All dynamically allocated data structures for this stream are freed.
|
|---|
| 436 | This function discards any unprocessed input and does not flush any
|
|---|
| 437 | pending output.
|
|---|
| 438 |
|
|---|
| 439 | inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
|
|---|
| 440 | was inconsistent. In the error case, msg may be set but then points to a
|
|---|
| 441 | static string (which must not be deallocated).
|
|---|
| 442 | */
|
|---|
| 443 |
|
|---|
| 444 | /* Advanced functions */
|
|---|
| 445 |
|
|---|
| 446 | /*
|
|---|
| 447 | The following functions are needed only in some special applications.
|
|---|
| 448 | */
|
|---|
| 449 |
|
|---|
| 450 | /*
|
|---|
| 451 | ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
|
|---|
| 452 | int level,
|
|---|
| 453 | int method,
|
|---|
| 454 | int windowBits,
|
|---|
| 455 | int memLevel,
|
|---|
| 456 | int strategy));
|
|---|
| 457 |
|
|---|
| 458 | This is another version of deflateInit with more compression options. The
|
|---|
| 459 | fields next_in, zalloc, zfree and opaque must be initialized before by
|
|---|
| 460 | the caller.
|
|---|
| 461 |
|
|---|
| 462 | The method parameter is the compression method. It must be Z_DEFLATED in
|
|---|
| 463 | this version of the library.
|
|---|
| 464 |
|
|---|
| 465 | The windowBits parameter is the base two logarithm of the window size
|
|---|
| 466 | (the size of the history buffer). It should be in the range 8..15 for this
|
|---|
| 467 | version of the library. Larger values of this parameter result in better
|
|---|
| 468 | compression at the expense of memory usage. The default value is 15 if
|
|---|
| 469 | deflateInit is used instead.
|
|---|
| 470 |
|
|---|
| 471 | windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
|
|---|
| 472 | determines the window size. deflate() will then generate raw deflate data
|
|---|
| 473 | with no zlib header or trailer, and will not compute an adler32 check value.
|
|---|
| 474 |
|
|---|
| 475 | windowBits can also be greater than 15 for optional gzip encoding. Add
|
|---|
| 476 | 16 to windowBits to write a simple gzip header and trailer around the
|
|---|
| 477 | compressed data instead of a zlib wrapper. The gzip header will have no
|
|---|
| 478 | file name, no extra data, no comment, no modification time (set to zero),
|
|---|
| 479 | no header crc, and the operating system will be set to 255 (unknown). If a
|
|---|
| 480 | gzip stream is being written, strm->adler is a crc32 instead of an adler32.
|
|---|
| 481 |
|
|---|
| 482 | The memLevel parameter specifies how much memory should be allocated
|
|---|
| 483 | for the internal compression state. memLevel=1 uses minimum memory but
|
|---|
| 484 | is slow and reduces compression ratio; memLevel=9 uses maximum memory
|
|---|
| 485 | for optimal speed. The default value is 8. See zconf.h for total memory
|
|---|
| 486 | usage as a function of windowBits and memLevel.
|
|---|
| 487 |
|
|---|
| 488 | The strategy parameter is used to tune the compression algorithm. Use the
|
|---|
| 489 | value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
|
|---|
| 490 | filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
|
|---|
| 491 | string match), or Z_RLE to limit match distances to one (run-length
|
|---|
| 492 | encoding). Filtered data consists mostly of small values with a somewhat
|
|---|
| 493 | random distribution. In this case, the compression algorithm is tuned to
|
|---|
| 494 | compress them better. The effect of Z_FILTERED is to force more Huffman
|
|---|
| 495 | coding and less string matching; it is somewhat intermediate between
|
|---|
| 496 | Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
|
|---|
| 497 | Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
|
|---|
| 498 | parameter only affects the compression ratio but not the correctness of the
|
|---|
| 499 | compressed output even if it is not set appropriately.
|
|---|
| 500 |
|
|---|
| 501 | deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
|---|
| 502 | memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
|
|---|
| 503 | method). msg is set to null if there is no error message. deflateInit2 does
|
|---|
| 504 | not perform any compression: this will be done by deflate().
|
|---|
| 505 | */
|
|---|
| 506 |
|
|---|
| 507 | ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
|
|---|
| 508 | const Bytef *dictionary,
|
|---|
| 509 | uInt dictLength));
|
|---|
| 510 | /*
|
|---|
| 511 | Initializes the compression dictionary from the given byte sequence
|
|---|
| 512 | without producing any compressed output. This function must be called
|
|---|
| 513 | immediately after deflateInit, deflateInit2 or deflateReset, before any
|
|---|
| 514 | call of deflate. The compressor and decompressor must use exactly the same
|
|---|
| 515 | dictionary (see inflateSetDictionary).
|
|---|
| 516 |
|
|---|
| 517 | The dictionary should consist of strings (byte sequences) that are likely
|
|---|
| 518 | to be encountered later in the data to be compressed, with the most commonly
|
|---|
| 519 | used strings preferably put towards the end of the dictionary. Using a
|
|---|
| 520 | dictionary is most useful when the data to be compressed is short and can be
|
|---|
| 521 | predicted with good accuracy; the data can then be compressed better than
|
|---|
| 522 | with the default empty dictionary.
|
|---|
| 523 |
|
|---|
| 524 | Depending on the size of the compression data structures selected by
|
|---|
| 525 | deflateInit or deflateInit2, a part of the dictionary may in effect be
|
|---|
| 526 | discarded, for example if the dictionary is larger than the window size in
|
|---|
| 527 | deflate or deflate2. Thus the strings most likely to be useful should be
|
|---|
| 528 | put at the end of the dictionary, not at the front.
|
|---|
| 529 |
|
|---|
| 530 | Upon return of this function, strm->adler is set to the adler32 value
|
|---|
| 531 | of the dictionary; the decompressor may later use this value to determine
|
|---|
| 532 | which dictionary has been used by the compressor. (The adler32 value
|
|---|
| 533 | applies to the whole dictionary even if only a subset of the dictionary is
|
|---|
| 534 | actually used by the compressor.) If a raw deflate was requested, then the
|
|---|
| 535 | adler32 value is not computed and strm->adler is not set.
|
|---|
| 536 |
|
|---|
| 537 | deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
|
|---|
| 538 | parameter is invalid (such as NULL dictionary) or the stream state is
|
|---|
| 539 | inconsistent (for example if deflate has already been called for this stream
|
|---|
| 540 | or if the compression method is bsort). deflateSetDictionary does not
|
|---|
| 541 | perform any compression: this will be done by deflate().
|
|---|
| 542 | */
|
|---|
| 543 |
|
|---|
| 544 | ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
|
|---|
| 545 | z_streamp source));
|
|---|
| 546 | /*
|
|---|
| 547 | Sets the destination stream as a complete copy of the source stream.
|
|---|
| 548 |
|
|---|
| 549 | This function can be useful when several compression strategies will be
|
|---|
| 550 | tried, for example when there are several ways of pre-processing the input
|
|---|
| 551 | data with a filter. The streams that will be discarded should then be freed
|
|---|
| 552 | by calling deflateEnd. Note that deflateCopy duplicates the internal
|
|---|
| 553 | compression state which can be quite large, so this strategy is slow and
|
|---|
| 554 | can consume lots of memory.
|
|---|
| 555 |
|
|---|
| 556 | deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
|
|---|
| 557 | enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
|
|---|
| 558 | (such as zalloc being NULL). msg is left unchanged in both source and
|
|---|
| 559 | destination.
|
|---|
| 560 | */
|
|---|
| 561 |
|
|---|
| 562 | ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
|
|---|
| 563 | /*
|
|---|
| 564 | This function is equivalent to deflateEnd followed by deflateInit,
|
|---|
| 565 | but does not free and reallocate all the internal compression state.
|
|---|
| 566 | The stream will keep the same compression level and any other attributes
|
|---|
| 567 | that may have been set by deflateInit2.
|
|---|
| 568 |
|
|---|
| 569 | deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|---|
| 570 | stream state was inconsistent (such as zalloc or state being NULL).
|
|---|
| 571 | */
|
|---|
| 572 |
|
|---|
| 573 | ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
|
|---|
| 574 | int level,
|
|---|
| 575 | int strategy));
|
|---|
| 576 | /*
|
|---|
| 577 | Dynamically update the compression level and compression strategy. The
|
|---|
| 578 | interpretation of level and strategy is as in deflateInit2. This can be
|
|---|
| 579 | used to switch between compression and straight copy of the input data, or
|
|---|
| 580 | to switch to a different kind of input data requiring a different
|
|---|
| 581 | strategy. If the compression level is changed, the input available so far
|
|---|
| 582 | is compressed with the old level (and may be flushed); the new level will
|
|---|
| 583 | take effect only at the next call of deflate().
|
|---|
| 584 |
|
|---|
| 585 | Before the call of deflateParams, the stream state must be set as for
|
|---|
| 586 | a call of deflate(), since the currently available input may have to
|
|---|
| 587 | be compressed and flushed. In particular, strm->avail_out must be non-zero.
|
|---|
| 588 |
|
|---|
| 589 | deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
|
|---|
| 590 | stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
|
|---|
| 591 | if strm->avail_out was zero.
|
|---|
| 592 | */
|
|---|
| 593 |
|
|---|
| 594 | ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
|
|---|
| 595 | uLong sourceLen));
|
|---|
| 596 | /*
|
|---|
| 597 | deflateBound() returns an upper bound on the compressed size after
|
|---|
| 598 | deflation of sourceLen bytes. It must be called after deflateInit()
|
|---|
| 599 | or deflateInit2(). This would be used to allocate an output buffer
|
|---|
| 600 | for deflation in a single pass, and so would be called before deflate().
|
|---|
| 601 | */
|
|---|
| 602 |
|
|---|
| 603 | ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
|
|---|
| 604 | int bits,
|
|---|
| 605 | int value));
|
|---|
| 606 | /*
|
|---|
| 607 | deflatePrime() inserts bits in the deflate output stream. The intent
|
|---|
| 608 | is that this function is used to start off the deflate output with the
|
|---|
| 609 | bits leftover from a previous deflate stream when appending to it. As such,
|
|---|
| 610 | this function can only be used for raw deflate, and must be used before the
|
|---|
| 611 | first deflate() call after a deflateInit2() or deflateReset(). bits must be
|
|---|
| 612 | less than or equal to 16, and that many of the least significant bits of
|
|---|
| 613 | value will be inserted in the output.
|
|---|
| 614 |
|
|---|
| 615 | deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
|
|---|
| 616 | stream state was inconsistent.
|
|---|
| 617 | */
|
|---|
| 618 |
|
|---|
| 619 | /*
|
|---|
| 620 | ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
|
|---|
| 621 | int windowBits));
|
|---|
| 622 |
|
|---|
| 623 | This is another version of inflateInit with an extra parameter. The
|
|---|
| 624 | fields next_in, avail_in, zalloc, zfree and opaque must be initialized
|
|---|
| 625 | before by the caller.
|
|---|
| 626 |
|
|---|
| 627 | The windowBits parameter is the base two logarithm of the maximum window
|
|---|
| 628 | size (the size of the history buffer). It should be in the range 8..15 for
|
|---|
| 629 | this version of the library. The default value is 15 if inflateInit is used
|
|---|
| 630 | instead. windowBits must be greater than or equal to the windowBits value
|
|---|
| 631 | provided to deflateInit2() while compressing, or it must be equal to 15 if
|
|---|
| 632 | deflateInit2() was not used. If a compressed stream with a larger window
|
|---|
| 633 | size is given as input, inflate() will return with the error code
|
|---|
| 634 | Z_DATA_ERROR instead of trying to allocate a larger window.
|
|---|
| 635 |
|
|---|
| 636 | windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
|
|---|
| 637 | determines the window size. inflate() will then process raw deflate data,
|
|---|
| 638 | not looking for a zlib or gzip header, not generating a check value, and not
|
|---|
| 639 | looking for any check values for comparison at the end of the stream. This
|
|---|
| 640 | is for use with other formats that use the deflate compressed data format
|
|---|
| 641 | such as zip. Those formats provide their own check values. If a custom
|
|---|
| 642 | format is developed using the raw deflate format for compressed data, it is
|
|---|
| 643 | recommended that a check value such as an adler32 or a crc32 be applied to
|
|---|
| 644 | the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
|---|
| 645 | most applications, the zlib format should be used as is. Note that comments
|
|---|
| 646 | above on the use in deflateInit2() applies to the magnitude of windowBits.
|
|---|
| 647 |
|
|---|
| 648 | windowBits can also be greater than 15 for optional gzip decoding. Add
|
|---|
| 649 | 32 to windowBits to enable zlib and gzip decoding with automatic header
|
|---|
| 650 | detection, or add 16 to decode only the gzip format (the zlib format will
|
|---|
| 651 | return a Z_DATA_ERROR. If a gzip stream is being decoded, strm->adler is
|
|---|
| 652 | a crc32 instead of an adler32.
|
|---|
| 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 | #if !defined(_ZUTIL_H) && !defined(NO_DUMMY_DECL)
|
|---|
| 1188 | struct internal_state {int dummy;}; /* hack for buggy compilers */
|
|---|
| 1189 | #endif
|
|---|
| 1190 |
|
|---|
| 1191 | ZEXTERN const char * ZEXPORT zError OF((int));
|
|---|
| 1192 | ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
|
|---|
| 1193 | ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
|
|---|
| 1194 |
|
|---|
| 1195 | #ifdef __cplusplus
|
|---|
| 1196 | }
|
|---|
| 1197 | #endif
|
|---|
| 1198 |
|
|---|
| 1199 | #endif /* _ZLIB_H */
|
|---|