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annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/zlib.h @ 69:33d812a61356

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
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jpayne@69 1 /* zlib.h -- interface of the 'zlib' general purpose compression library
jpayne@69 2 version 1.2.13, October 13th, 2022
jpayne@69 3
jpayne@69 4 Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler
jpayne@69 5
jpayne@69 6 This software is provided 'as-is', without any express or implied
jpayne@69 7 warranty. In no event will the authors be held liable for any damages
jpayne@69 8 arising from the use of this software.
jpayne@69 9
jpayne@69 10 Permission is granted to anyone to use this software for any purpose,
jpayne@69 11 including commercial applications, and to alter it and redistribute it
jpayne@69 12 freely, subject to the following restrictions:
jpayne@69 13
jpayne@69 14 1. The origin of this software must not be misrepresented; you must not
jpayne@69 15 claim that you wrote the original software. If you use this software
jpayne@69 16 in a product, an acknowledgment in the product documentation would be
jpayne@69 17 appreciated but is not required.
jpayne@69 18 2. Altered source versions must be plainly marked as such, and must not be
jpayne@69 19 misrepresented as being the original software.
jpayne@69 20 3. This notice may not be removed or altered from any source distribution.
jpayne@69 21
jpayne@69 22 Jean-loup Gailly Mark Adler
jpayne@69 23 jloup@gzip.org madler@alumni.caltech.edu
jpayne@69 24
jpayne@69 25
jpayne@69 26 The data format used by the zlib library is described by RFCs (Request for
jpayne@69 27 Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
jpayne@69 28 (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
jpayne@69 29 */
jpayne@69 30
jpayne@69 31 #ifndef ZLIB_H
jpayne@69 32 #define ZLIB_H
jpayne@69 33
jpayne@69 34 #include "zconf.h"
jpayne@69 35
jpayne@69 36 #ifdef __cplusplus
jpayne@69 37 extern "C" {
jpayne@69 38 #endif
jpayne@69 39
jpayne@69 40 #define ZLIB_VERSION "1.2.13"
jpayne@69 41 #define ZLIB_VERNUM 0x12d0
jpayne@69 42 #define ZLIB_VER_MAJOR 1
jpayne@69 43 #define ZLIB_VER_MINOR 2
jpayne@69 44 #define ZLIB_VER_REVISION 13
jpayne@69 45 #define ZLIB_VER_SUBREVISION 0
jpayne@69 46
jpayne@69 47 /*
jpayne@69 48 The 'zlib' compression library provides in-memory compression and
jpayne@69 49 decompression functions, including integrity checks of the uncompressed data.
jpayne@69 50 This version of the library supports only one compression method (deflation)
jpayne@69 51 but other algorithms will be added later and will have the same stream
jpayne@69 52 interface.
jpayne@69 53
jpayne@69 54 Compression can be done in a single step if the buffers are large enough,
jpayne@69 55 or can be done by repeated calls of the compression function. In the latter
jpayne@69 56 case, the application must provide more input and/or consume the output
jpayne@69 57 (providing more output space) before each call.
jpayne@69 58
jpayne@69 59 The compressed data format used by default by the in-memory functions is
jpayne@69 60 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
jpayne@69 61 around a deflate stream, which is itself documented in RFC 1951.
jpayne@69 62
jpayne@69 63 The library also supports reading and writing files in gzip (.gz) format
jpayne@69 64 with an interface similar to that of stdio using the functions that start
jpayne@69 65 with "gz". The gzip format is different from the zlib format. gzip is a
jpayne@69 66 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
jpayne@69 67
jpayne@69 68 This library can optionally read and write gzip and raw deflate streams in
jpayne@69 69 memory as well.
jpayne@69 70
jpayne@69 71 The zlib format was designed to be compact and fast for use in memory
jpayne@69 72 and on communications channels. The gzip format was designed for single-
jpayne@69 73 file compression on file systems, has a larger header than zlib to maintain
jpayne@69 74 directory information, and uses a different, slower check method than zlib.
jpayne@69 75
jpayne@69 76 The library does not install any signal handler. The decoder checks
jpayne@69 77 the consistency of the compressed data, so the library should never crash
jpayne@69 78 even in the case of corrupted input.
jpayne@69 79 */
jpayne@69 80
jpayne@69 81 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
jpayne@69 82 typedef void (*free_func) OF((voidpf opaque, voidpf address));
jpayne@69 83
jpayne@69 84 struct internal_state;
jpayne@69 85
jpayne@69 86 typedef struct z_stream_s {
jpayne@69 87 z_const Bytef *next_in; /* next input byte */
jpayne@69 88 uInt avail_in; /* number of bytes available at next_in */
jpayne@69 89 uLong total_in; /* total number of input bytes read so far */
jpayne@69 90
jpayne@69 91 Bytef *next_out; /* next output byte will go here */
jpayne@69 92 uInt avail_out; /* remaining free space at next_out */
jpayne@69 93 uLong total_out; /* total number of bytes output so far */
jpayne@69 94
jpayne@69 95 z_const char *msg; /* last error message, NULL if no error */
jpayne@69 96 struct internal_state FAR *state; /* not visible by applications */
jpayne@69 97
jpayne@69 98 alloc_func zalloc; /* used to allocate the internal state */
jpayne@69 99 free_func zfree; /* used to free the internal state */
jpayne@69 100 voidpf opaque; /* private data object passed to zalloc and zfree */
jpayne@69 101
jpayne@69 102 int data_type; /* best guess about the data type: binary or text
jpayne@69 103 for deflate, or the decoding state for inflate */
jpayne@69 104 uLong adler; /* Adler-32 or CRC-32 value of the uncompressed data */
jpayne@69 105 uLong reserved; /* reserved for future use */
jpayne@69 106 } z_stream;
jpayne@69 107
jpayne@69 108 typedef z_stream FAR *z_streamp;
jpayne@69 109
jpayne@69 110 /*
jpayne@69 111 gzip header information passed to and from zlib routines. See RFC 1952
jpayne@69 112 for more details on the meanings of these fields.
jpayne@69 113 */
jpayne@69 114 typedef struct gz_header_s {
jpayne@69 115 int text; /* true if compressed data believed to be text */
jpayne@69 116 uLong time; /* modification time */
jpayne@69 117 int xflags; /* extra flags (not used when writing a gzip file) */
jpayne@69 118 int os; /* operating system */
jpayne@69 119 Bytef *extra; /* pointer to extra field or Z_NULL if none */
jpayne@69 120 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
jpayne@69 121 uInt extra_max; /* space at extra (only when reading header) */
jpayne@69 122 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
jpayne@69 123 uInt name_max; /* space at name (only when reading header) */
jpayne@69 124 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
jpayne@69 125 uInt comm_max; /* space at comment (only when reading header) */
jpayne@69 126 int hcrc; /* true if there was or will be a header crc */
jpayne@69 127 int done; /* true when done reading gzip header (not used
jpayne@69 128 when writing a gzip file) */
jpayne@69 129 } gz_header;
jpayne@69 130
jpayne@69 131 typedef gz_header FAR *gz_headerp;
jpayne@69 132
jpayne@69 133 /*
jpayne@69 134 The application must update next_in and avail_in when avail_in has dropped
jpayne@69 135 to zero. It must update next_out and avail_out when avail_out has dropped
jpayne@69 136 to zero. The application must initialize zalloc, zfree and opaque before
jpayne@69 137 calling the init function. All other fields are set by the compression
jpayne@69 138 library and must not be updated by the application.
jpayne@69 139
jpayne@69 140 The opaque value provided by the application will be passed as the first
jpayne@69 141 parameter for calls of zalloc and zfree. This can be useful for custom
jpayne@69 142 memory management. The compression library attaches no meaning to the
jpayne@69 143 opaque value.
jpayne@69 144
jpayne@69 145 zalloc must return Z_NULL if there is not enough memory for the object.
jpayne@69 146 If zlib is used in a multi-threaded application, zalloc and zfree must be
jpayne@69 147 thread safe. In that case, zlib is thread-safe. When zalloc and zfree are
jpayne@69 148 Z_NULL on entry to the initialization function, they are set to internal
jpayne@69 149 routines that use the standard library functions malloc() and free().
jpayne@69 150
jpayne@69 151 On 16-bit systems, the functions zalloc and zfree must be able to allocate
jpayne@69 152 exactly 65536 bytes, but will not be required to allocate more than this if
jpayne@69 153 the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers
jpayne@69 154 returned by zalloc for objects of exactly 65536 bytes *must* have their
jpayne@69 155 offset normalized to zero. The default allocation function provided by this
jpayne@69 156 library ensures this (see zutil.c). To reduce memory requirements and avoid
jpayne@69 157 any allocation of 64K objects, at the expense of compression ratio, compile
jpayne@69 158 the library with -DMAX_WBITS=14 (see zconf.h).
jpayne@69 159
jpayne@69 160 The fields total_in and total_out can be used for statistics or progress
jpayne@69 161 reports. After compression, total_in holds the total size of the
jpayne@69 162 uncompressed data and may be saved for use by the decompressor (particularly
jpayne@69 163 if the decompressor wants to decompress everything in a single step).
jpayne@69 164 */
jpayne@69 165
jpayne@69 166 /* constants */
jpayne@69 167
jpayne@69 168 #define Z_NO_FLUSH 0
jpayne@69 169 #define Z_PARTIAL_FLUSH 1
jpayne@69 170 #define Z_SYNC_FLUSH 2
jpayne@69 171 #define Z_FULL_FLUSH 3
jpayne@69 172 #define Z_FINISH 4
jpayne@69 173 #define Z_BLOCK 5
jpayne@69 174 #define Z_TREES 6
jpayne@69 175 /* Allowed flush values; see deflate() and inflate() below for details */
jpayne@69 176
jpayne@69 177 #define Z_OK 0
jpayne@69 178 #define Z_STREAM_END 1
jpayne@69 179 #define Z_NEED_DICT 2
jpayne@69 180 #define Z_ERRNO (-1)
jpayne@69 181 #define Z_STREAM_ERROR (-2)
jpayne@69 182 #define Z_DATA_ERROR (-3)
jpayne@69 183 #define Z_MEM_ERROR (-4)
jpayne@69 184 #define Z_BUF_ERROR (-5)
jpayne@69 185 #define Z_VERSION_ERROR (-6)
jpayne@69 186 /* Return codes for the compression/decompression functions. Negative values
jpayne@69 187 * are errors, positive values are used for special but normal events.
jpayne@69 188 */
jpayne@69 189
jpayne@69 190 #define Z_NO_COMPRESSION 0
jpayne@69 191 #define Z_BEST_SPEED 1
jpayne@69 192 #define Z_BEST_COMPRESSION 9
jpayne@69 193 #define Z_DEFAULT_COMPRESSION (-1)
jpayne@69 194 /* compression levels */
jpayne@69 195
jpayne@69 196 #define Z_FILTERED 1
jpayne@69 197 #define Z_HUFFMAN_ONLY 2
jpayne@69 198 #define Z_RLE 3
jpayne@69 199 #define Z_FIXED 4
jpayne@69 200 #define Z_DEFAULT_STRATEGY 0
jpayne@69 201 /* compression strategy; see deflateInit2() below for details */
jpayne@69 202
jpayne@69 203 #define Z_BINARY 0
jpayne@69 204 #define Z_TEXT 1
jpayne@69 205 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
jpayne@69 206 #define Z_UNKNOWN 2
jpayne@69 207 /* Possible values of the data_type field for deflate() */
jpayne@69 208
jpayne@69 209 #define Z_DEFLATED 8
jpayne@69 210 /* The deflate compression method (the only one supported in this version) */
jpayne@69 211
jpayne@69 212 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
jpayne@69 213
jpayne@69 214 #define zlib_version zlibVersion()
jpayne@69 215 /* for compatibility with versions < 1.0.2 */
jpayne@69 216
jpayne@69 217
jpayne@69 218 /* basic functions */
jpayne@69 219
jpayne@69 220 ZEXTERN const char * ZEXPORT zlibVersion OF((void));
jpayne@69 221 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
jpayne@69 222 If the first character differs, the library code actually used is not
jpayne@69 223 compatible with the zlib.h header file used by the application. This check
jpayne@69 224 is automatically made by deflateInit and inflateInit.
jpayne@69 225 */
jpayne@69 226
jpayne@69 227 /*
jpayne@69 228 ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
jpayne@69 229
jpayne@69 230 Initializes the internal stream state for compression. The fields
jpayne@69 231 zalloc, zfree and opaque must be initialized before by the caller. If
jpayne@69 232 zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
jpayne@69 233 allocation functions.
jpayne@69 234
jpayne@69 235 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
jpayne@69 236 1 gives best speed, 9 gives best compression, 0 gives no compression at all
jpayne@69 237 (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION
jpayne@69 238 requests a default compromise between speed and compression (currently
jpayne@69 239 equivalent to level 6).
jpayne@69 240
jpayne@69 241 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
jpayne@69 242 memory, Z_STREAM_ERROR if level is not a valid compression level, or
jpayne@69 243 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
jpayne@69 244 with the version assumed by the caller (ZLIB_VERSION). msg is set to null
jpayne@69 245 if there is no error message. deflateInit does not perform any compression:
jpayne@69 246 this will be done by deflate().
jpayne@69 247 */
jpayne@69 248
jpayne@69 249
jpayne@69 250 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
jpayne@69 251 /*
jpayne@69 252 deflate compresses as much data as possible, and stops when the input
jpayne@69 253 buffer becomes empty or the output buffer becomes full. It may introduce
jpayne@69 254 some output latency (reading input without producing any output) except when
jpayne@69 255 forced to flush.
jpayne@69 256
jpayne@69 257 The detailed semantics are as follows. deflate performs one or both of the
jpayne@69 258 following actions:
jpayne@69 259
jpayne@69 260 - Compress more input starting at next_in and update next_in and avail_in
jpayne@69 261 accordingly. If not all input can be processed (because there is not
jpayne@69 262 enough room in the output buffer), next_in and avail_in are updated and
jpayne@69 263 processing will resume at this point for the next call of deflate().
jpayne@69 264
jpayne@69 265 - Generate more output starting at next_out and update next_out and avail_out
jpayne@69 266 accordingly. This action is forced if the parameter flush is non zero.
jpayne@69 267 Forcing flush frequently degrades the compression ratio, so this parameter
jpayne@69 268 should be set only when necessary. Some output may be provided even if
jpayne@69 269 flush is zero.
jpayne@69 270
jpayne@69 271 Before the call of deflate(), the application should ensure that at least
jpayne@69 272 one of the actions is possible, by providing more input and/or consuming more
jpayne@69 273 output, and updating avail_in or avail_out accordingly; avail_out should
jpayne@69 274 never be zero before the call. The application can consume the compressed
jpayne@69 275 output when it wants, for example when the output buffer is full (avail_out
jpayne@69 276 == 0), or after each call of deflate(). If deflate returns Z_OK and with
jpayne@69 277 zero avail_out, it must be called again after making room in the output
jpayne@69 278 buffer because there might be more output pending. See deflatePending(),
jpayne@69 279 which can be used if desired to determine whether or not there is more output
jpayne@69 280 in that case.
jpayne@69 281
jpayne@69 282 Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
jpayne@69 283 decide how much data to accumulate before producing output, in order to
jpayne@69 284 maximize compression.
jpayne@69 285
jpayne@69 286 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
jpayne@69 287 flushed to the output buffer and the output is aligned on a byte boundary, so
jpayne@69 288 that the decompressor can get all input data available so far. (In
jpayne@69 289 particular avail_in is zero after the call if enough output space has been
jpayne@69 290 provided before the call.) Flushing may degrade compression for some
jpayne@69 291 compression algorithms and so it should be used only when necessary. This
jpayne@69 292 completes the current deflate block and follows it with an empty stored block
jpayne@69 293 that is three bits plus filler bits to the next byte, followed by four bytes
jpayne@69 294 (00 00 ff ff).
jpayne@69 295
jpayne@69 296 If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
jpayne@69 297 output buffer, but the output is not aligned to a byte boundary. All of the
jpayne@69 298 input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
jpayne@69 299 This completes the current deflate block and follows it with an empty fixed
jpayne@69 300 codes block that is 10 bits long. This assures that enough bytes are output
jpayne@69 301 in order for the decompressor to finish the block before the empty fixed
jpayne@69 302 codes block.
jpayne@69 303
jpayne@69 304 If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
jpayne@69 305 for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
jpayne@69 306 seven bits of the current block are held to be written as the next byte after
jpayne@69 307 the next deflate block is completed. In this case, the decompressor may not
jpayne@69 308 be provided enough bits at this point in order to complete decompression of
jpayne@69 309 the data provided so far to the compressor. It may need to wait for the next
jpayne@69 310 block to be emitted. This is for advanced applications that need to control
jpayne@69 311 the emission of deflate blocks.
jpayne@69 312
jpayne@69 313 If flush is set to Z_FULL_FLUSH, all output is flushed as with
jpayne@69 314 Z_SYNC_FLUSH, and the compression state is reset so that decompression can
jpayne@69 315 restart from this point if previous compressed data has been damaged or if
jpayne@69 316 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
jpayne@69 317 compression.
jpayne@69 318
jpayne@69 319 If deflate returns with avail_out == 0, this function must be called again
jpayne@69 320 with the same value of the flush parameter and more output space (updated
jpayne@69 321 avail_out), until the flush is complete (deflate returns with non-zero
jpayne@69 322 avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
jpayne@69 323 avail_out is greater than six to avoid repeated flush markers due to
jpayne@69 324 avail_out == 0 on return.
jpayne@69 325
jpayne@69 326 If the parameter flush is set to Z_FINISH, pending input is processed,
jpayne@69 327 pending output is flushed and deflate returns with Z_STREAM_END if there was
jpayne@69 328 enough output space. If deflate returns with Z_OK or Z_BUF_ERROR, this
jpayne@69 329 function must be called again with Z_FINISH and more output space (updated
jpayne@69 330 avail_out) but no more input data, until it returns with Z_STREAM_END or an
jpayne@69 331 error. After deflate has returned Z_STREAM_END, the only possible operations
jpayne@69 332 on the stream are deflateReset or deflateEnd.
jpayne@69 333
jpayne@69 334 Z_FINISH can be used in the first deflate call after deflateInit if all the
jpayne@69 335 compression is to be done in a single step. In order to complete in one
jpayne@69 336 call, avail_out must be at least the value returned by deflateBound (see
jpayne@69 337 below). Then deflate is guaranteed to return Z_STREAM_END. If not enough
jpayne@69 338 output space is provided, deflate will not return Z_STREAM_END, and it must
jpayne@69 339 be called again as described above.
jpayne@69 340
jpayne@69 341 deflate() sets strm->adler to the Adler-32 checksum of all input read
jpayne@69 342 so far (that is, total_in bytes). If a gzip stream is being generated, then
jpayne@69 343 strm->adler will be the CRC-32 checksum of the input read so far. (See
jpayne@69 344 deflateInit2 below.)
jpayne@69 345
jpayne@69 346 deflate() may update strm->data_type if it can make a good guess about
jpayne@69 347 the input data type (Z_BINARY or Z_TEXT). If in doubt, the data is
jpayne@69 348 considered binary. This field is only for information purposes and does not
jpayne@69 349 affect the compression algorithm in any manner.
jpayne@69 350
jpayne@69 351 deflate() returns Z_OK if some progress has been made (more input
jpayne@69 352 processed or more output produced), Z_STREAM_END if all input has been
jpayne@69 353 consumed and all output has been produced (only when flush is set to
jpayne@69 354 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
jpayne@69 355 if next_in or next_out was Z_NULL or the state was inadvertently written over
jpayne@69 356 by the application), or Z_BUF_ERROR if no progress is possible (for example
jpayne@69 357 avail_in or avail_out was zero). Note that Z_BUF_ERROR is not fatal, and
jpayne@69 358 deflate() can be called again with more input and more output space to
jpayne@69 359 continue compressing.
jpayne@69 360 */
jpayne@69 361
jpayne@69 362
jpayne@69 363 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
jpayne@69 364 /*
jpayne@69 365 All dynamically allocated data structures for this stream are freed.
jpayne@69 366 This function discards any unprocessed input and does not flush any pending
jpayne@69 367 output.
jpayne@69 368
jpayne@69 369 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
jpayne@69 370 stream state was inconsistent, Z_DATA_ERROR if the stream was freed
jpayne@69 371 prematurely (some input or output was discarded). In the error case, msg
jpayne@69 372 may be set but then points to a static string (which must not be
jpayne@69 373 deallocated).
jpayne@69 374 */
jpayne@69 375
jpayne@69 376
jpayne@69 377 /*
jpayne@69 378 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
jpayne@69 379
jpayne@69 380 Initializes the internal stream state for decompression. The fields
jpayne@69 381 next_in, avail_in, zalloc, zfree and opaque must be initialized before by
jpayne@69 382 the caller. In the current version of inflate, the provided input is not
jpayne@69 383 read or consumed. The allocation of a sliding window will be deferred to
jpayne@69 384 the first call of inflate (if the decompression does not complete on the
jpayne@69 385 first call). If zalloc and zfree are set to Z_NULL, inflateInit updates
jpayne@69 386 them to use default allocation functions.
jpayne@69 387
jpayne@69 388 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
jpayne@69 389 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
jpayne@69 390 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
jpayne@69 391 invalid, such as a null pointer to the structure. msg is set to null if
jpayne@69 392 there is no error message. inflateInit does not perform any decompression.
jpayne@69 393 Actual decompression will be done by inflate(). So next_in, and avail_in,
jpayne@69 394 next_out, and avail_out are unused and unchanged. The current
jpayne@69 395 implementation of inflateInit() does not process any header information --
jpayne@69 396 that is deferred until inflate() is called.
jpayne@69 397 */
jpayne@69 398
jpayne@69 399
jpayne@69 400 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
jpayne@69 401 /*
jpayne@69 402 inflate decompresses as much data as possible, and stops when the input
jpayne@69 403 buffer becomes empty or the output buffer becomes full. It may introduce
jpayne@69 404 some output latency (reading input without producing any output) except when
jpayne@69 405 forced to flush.
jpayne@69 406
jpayne@69 407 The detailed semantics are as follows. inflate performs one or both of the
jpayne@69 408 following actions:
jpayne@69 409
jpayne@69 410 - Decompress more input starting at next_in and update next_in and avail_in
jpayne@69 411 accordingly. If not all input can be processed (because there is not
jpayne@69 412 enough room in the output buffer), then next_in and avail_in are updated
jpayne@69 413 accordingly, and processing will resume at this point for the next call of
jpayne@69 414 inflate().
jpayne@69 415
jpayne@69 416 - Generate more output starting at next_out and update next_out and avail_out
jpayne@69 417 accordingly. inflate() provides as much output as possible, until there is
jpayne@69 418 no more input data or no more space in the output buffer (see below about
jpayne@69 419 the flush parameter).
jpayne@69 420
jpayne@69 421 Before the call of inflate(), the application should ensure that at least
jpayne@69 422 one of the actions is possible, by providing more input and/or consuming more
jpayne@69 423 output, and updating the next_* and avail_* values accordingly. If the
jpayne@69 424 caller of inflate() does not provide both available input and available
jpayne@69 425 output space, it is possible that there will be no progress made. The
jpayne@69 426 application can consume the uncompressed output when it wants, for example
jpayne@69 427 when the output buffer is full (avail_out == 0), or after each call of
jpayne@69 428 inflate(). If inflate returns Z_OK and with zero avail_out, it must be
jpayne@69 429 called again after making room in the output buffer because there might be
jpayne@69 430 more output pending.
jpayne@69 431
jpayne@69 432 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
jpayne@69 433 Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much
jpayne@69 434 output as possible to the output buffer. Z_BLOCK requests that inflate()
jpayne@69 435 stop if and when it gets to the next deflate block boundary. When decoding
jpayne@69 436 the zlib or gzip format, this will cause inflate() to return immediately
jpayne@69 437 after the header and before the first block. When doing a raw inflate,
jpayne@69 438 inflate() will go ahead and process the first block, and will return when it
jpayne@69 439 gets to the end of that block, or when it runs out of data.
jpayne@69 440
jpayne@69 441 The Z_BLOCK option assists in appending to or combining deflate streams.
jpayne@69 442 To assist in this, on return inflate() always sets strm->data_type to the
jpayne@69 443 number of unused bits in the last byte taken from strm->next_in, plus 64 if
jpayne@69 444 inflate() is currently decoding the last block in the deflate stream, plus
jpayne@69 445 128 if inflate() returned immediately after decoding an end-of-block code or
jpayne@69 446 decoding the complete header up to just before the first byte of the deflate
jpayne@69 447 stream. The end-of-block will not be indicated until all of the uncompressed
jpayne@69 448 data from that block has been written to strm->next_out. The number of
jpayne@69 449 unused bits may in general be greater than seven, except when bit 7 of
jpayne@69 450 data_type is set, in which case the number of unused bits will be less than
jpayne@69 451 eight. data_type is set as noted here every time inflate() returns for all
jpayne@69 452 flush options, and so can be used to determine the amount of currently
jpayne@69 453 consumed input in bits.
jpayne@69 454
jpayne@69 455 The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
jpayne@69 456 end of each deflate block header is reached, before any actual data in that
jpayne@69 457 block is decoded. This allows the caller to determine the length of the
jpayne@69 458 deflate block header for later use in random access within a deflate block.
jpayne@69 459 256 is added to the value of strm->data_type when inflate() returns
jpayne@69 460 immediately after reaching the end of the deflate block header.
jpayne@69 461
jpayne@69 462 inflate() should normally be called until it returns Z_STREAM_END or an
jpayne@69 463 error. However if all decompression is to be performed in a single step (a
jpayne@69 464 single call of inflate), the parameter flush should be set to Z_FINISH. In
jpayne@69 465 this case all pending input is processed and all pending output is flushed;
jpayne@69 466 avail_out must be large enough to hold all of the uncompressed data for the
jpayne@69 467 operation to complete. (The size of the uncompressed data may have been
jpayne@69 468 saved by the compressor for this purpose.) The use of Z_FINISH is not
jpayne@69 469 required to perform an inflation in one step. However it may be used to
jpayne@69 470 inform inflate that a faster approach can be used for the single inflate()
jpayne@69 471 call. Z_FINISH also informs inflate to not maintain a sliding window if the
jpayne@69 472 stream completes, which reduces inflate's memory footprint. If the stream
jpayne@69 473 does not complete, either because not all of the stream is provided or not
jpayne@69 474 enough output space is provided, then a sliding window will be allocated and
jpayne@69 475 inflate() can be called again to continue the operation as if Z_NO_FLUSH had
jpayne@69 476 been used.
jpayne@69 477
jpayne@69 478 In this implementation, inflate() always flushes as much output as
jpayne@69 479 possible to the output buffer, and always uses the faster approach on the
jpayne@69 480 first call. So the effects of the flush parameter in this implementation are
jpayne@69 481 on the return value of inflate() as noted below, when inflate() returns early
jpayne@69 482 when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
jpayne@69 483 memory for a sliding window when Z_FINISH is used.
jpayne@69 484
jpayne@69 485 If a preset dictionary is needed after this call (see inflateSetDictionary
jpayne@69 486 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
jpayne@69 487 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
jpayne@69 488 strm->adler to the Adler-32 checksum of all output produced so far (that is,
jpayne@69 489 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
jpayne@69 490 below. At the end of the stream, inflate() checks that its computed Adler-32
jpayne@69 491 checksum is equal to that saved by the compressor and returns Z_STREAM_END
jpayne@69 492 only if the checksum is correct.
jpayne@69 493
jpayne@69 494 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
jpayne@69 495 deflate data. The header type is detected automatically, if requested when
jpayne@69 496 initializing with inflateInit2(). Any information contained in the gzip
jpayne@69 497 header is not retained unless inflateGetHeader() is used. When processing
jpayne@69 498 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
jpayne@69 499 produced so far. The CRC-32 is checked against the gzip trailer, as is the
jpayne@69 500 uncompressed length, modulo 2^32.
jpayne@69 501
jpayne@69 502 inflate() returns Z_OK if some progress has been made (more input processed
jpayne@69 503 or more output produced), Z_STREAM_END if the end of the compressed data has
jpayne@69 504 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
jpayne@69 505 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
jpayne@69 506 corrupted (input stream not conforming to the zlib format or incorrect check
jpayne@69 507 value, in which case strm->msg points to a string with a more specific
jpayne@69 508 error), Z_STREAM_ERROR if the stream structure was inconsistent (for example
jpayne@69 509 next_in or next_out was Z_NULL, or the state was inadvertently written over
jpayne@69 510 by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR
jpayne@69 511 if no progress was possible or if there was not enough room in the output
jpayne@69 512 buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
jpayne@69 513 inflate() can be called again with more input and more output space to
jpayne@69 514 continue decompressing. If Z_DATA_ERROR is returned, the application may
jpayne@69 515 then call inflateSync() to look for a good compression block if a partial
jpayne@69 516 recovery of the data is to be attempted.
jpayne@69 517 */
jpayne@69 518
jpayne@69 519
jpayne@69 520 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
jpayne@69 521 /*
jpayne@69 522 All dynamically allocated data structures for this stream are freed.
jpayne@69 523 This function discards any unprocessed input and does not flush any pending
jpayne@69 524 output.
jpayne@69 525
jpayne@69 526 inflateEnd returns Z_OK if success, or Z_STREAM_ERROR if the stream state
jpayne@69 527 was inconsistent.
jpayne@69 528 */
jpayne@69 529
jpayne@69 530
jpayne@69 531 /* Advanced functions */
jpayne@69 532
jpayne@69 533 /*
jpayne@69 534 The following functions are needed only in some special applications.
jpayne@69 535 */
jpayne@69 536
jpayne@69 537 /*
jpayne@69 538 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
jpayne@69 539 int level,
jpayne@69 540 int method,
jpayne@69 541 int windowBits,
jpayne@69 542 int memLevel,
jpayne@69 543 int strategy));
jpayne@69 544
jpayne@69 545 This is another version of deflateInit with more compression options. The
jpayne@69 546 fields zalloc, zfree and opaque must be initialized before by the caller.
jpayne@69 547
jpayne@69 548 The method parameter is the compression method. It must be Z_DEFLATED in
jpayne@69 549 this version of the library.
jpayne@69 550
jpayne@69 551 The windowBits parameter is the base two logarithm of the window size
jpayne@69 552 (the size of the history buffer). It should be in the range 8..15 for this
jpayne@69 553 version of the library. Larger values of this parameter result in better
jpayne@69 554 compression at the expense of memory usage. The default value is 15 if
jpayne@69 555 deflateInit is used instead.
jpayne@69 556
jpayne@69 557 For the current implementation of deflate(), a windowBits value of 8 (a
jpayne@69 558 window size of 256 bytes) is not supported. As a result, a request for 8
jpayne@69 559 will result in 9 (a 512-byte window). In that case, providing 8 to
jpayne@69 560 inflateInit2() will result in an error when the zlib header with 9 is
jpayne@69 561 checked against the initialization of inflate(). The remedy is to not use 8
jpayne@69 562 with deflateInit2() with this initialization, or at least in that case use 9
jpayne@69 563 with inflateInit2().
jpayne@69 564
jpayne@69 565 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
jpayne@69 566 determines the window size. deflate() will then generate raw deflate data
jpayne@69 567 with no zlib header or trailer, and will not compute a check value.
jpayne@69 568
jpayne@69 569 windowBits can also be greater than 15 for optional gzip encoding. Add
jpayne@69 570 16 to windowBits to write a simple gzip header and trailer around the
jpayne@69 571 compressed data instead of a zlib wrapper. The gzip header will have no
jpayne@69 572 file name, no extra data, no comment, no modification time (set to zero), no
jpayne@69 573 header crc, and the operating system will be set to the appropriate value,
jpayne@69 574 if the operating system was determined at compile time. If a gzip stream is
jpayne@69 575 being written, strm->adler is a CRC-32 instead of an Adler-32.
jpayne@69 576
jpayne@69 577 For raw deflate or gzip encoding, a request for a 256-byte window is
jpayne@69 578 rejected as invalid, since only the zlib header provides a means of
jpayne@69 579 transmitting the window size to the decompressor.
jpayne@69 580
jpayne@69 581 The memLevel parameter specifies how much memory should be allocated
jpayne@69 582 for the internal compression state. memLevel=1 uses minimum memory but is
jpayne@69 583 slow and reduces compression ratio; memLevel=9 uses maximum memory for
jpayne@69 584 optimal speed. The default value is 8. See zconf.h for total memory usage
jpayne@69 585 as a function of windowBits and memLevel.
jpayne@69 586
jpayne@69 587 The strategy parameter is used to tune the compression algorithm. Use the
jpayne@69 588 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
jpayne@69 589 filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
jpayne@69 590 string match), or Z_RLE to limit match distances to one (run-length
jpayne@69 591 encoding). Filtered data consists mostly of small values with a somewhat
jpayne@69 592 random distribution. In this case, the compression algorithm is tuned to
jpayne@69 593 compress them better. The effect of Z_FILTERED is to force more Huffman
jpayne@69 594 coding and less string matching; it is somewhat intermediate between
jpayne@69 595 Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as
jpayne@69 596 fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The
jpayne@69 597 strategy parameter only affects the compression ratio but not the
jpayne@69 598 correctness of the compressed output even if it is not set appropriately.
jpayne@69 599 Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
jpayne@69 600 decoder for special applications.
jpayne@69 601
jpayne@69 602 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
jpayne@69 603 memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
jpayne@69 604 method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
jpayne@69 605 incompatible with the version assumed by the caller (ZLIB_VERSION). msg is
jpayne@69 606 set to null if there is no error message. deflateInit2 does not perform any
jpayne@69 607 compression: this will be done by deflate().
jpayne@69 608 */
jpayne@69 609
jpayne@69 610 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
jpayne@69 611 const Bytef *dictionary,
jpayne@69 612 uInt dictLength));
jpayne@69 613 /*
jpayne@69 614 Initializes the compression dictionary from the given byte sequence
jpayne@69 615 without producing any compressed output. When using the zlib format, this
jpayne@69 616 function must be called immediately after deflateInit, deflateInit2 or
jpayne@69 617 deflateReset, and before any call of deflate. When doing raw deflate, this
jpayne@69 618 function must be called either before any call of deflate, or immediately
jpayne@69 619 after the completion of a deflate block, i.e. after all input has been
jpayne@69 620 consumed and all output has been delivered when using any of the flush
jpayne@69 621 options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The
jpayne@69 622 compressor and decompressor must use exactly the same dictionary (see
jpayne@69 623 inflateSetDictionary).
jpayne@69 624
jpayne@69 625 The dictionary should consist of strings (byte sequences) that are likely
jpayne@69 626 to be encountered later in the data to be compressed, with the most commonly
jpayne@69 627 used strings preferably put towards the end of the dictionary. Using a
jpayne@69 628 dictionary is most useful when the data to be compressed is short and can be
jpayne@69 629 predicted with good accuracy; the data can then be compressed better than
jpayne@69 630 with the default empty dictionary.
jpayne@69 631
jpayne@69 632 Depending on the size of the compression data structures selected by
jpayne@69 633 deflateInit or deflateInit2, a part of the dictionary may in effect be
jpayne@69 634 discarded, for example if the dictionary is larger than the window size
jpayne@69 635 provided in deflateInit or deflateInit2. Thus the strings most likely to be
jpayne@69 636 useful should be put at the end of the dictionary, not at the front. In
jpayne@69 637 addition, the current implementation of deflate will use at most the window
jpayne@69 638 size minus 262 bytes of the provided dictionary.
jpayne@69 639
jpayne@69 640 Upon return of this function, strm->adler is set to the Adler-32 value
jpayne@69 641 of the dictionary; the decompressor may later use this value to determine
jpayne@69 642 which dictionary has been used by the compressor. (The Adler-32 value
jpayne@69 643 applies to the whole dictionary even if only a subset of the dictionary is
jpayne@69 644 actually used by the compressor.) If a raw deflate was requested, then the
jpayne@69 645 Adler-32 value is not computed and strm->adler is not set.
jpayne@69 646
jpayne@69 647 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
jpayne@69 648 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
jpayne@69 649 inconsistent (for example if deflate has already been called for this stream
jpayne@69 650 or if not at a block boundary for raw deflate). deflateSetDictionary does
jpayne@69 651 not perform any compression: this will be done by deflate().
jpayne@69 652 */
jpayne@69 653
jpayne@69 654 ZEXTERN int ZEXPORT deflateGetDictionary OF((z_streamp strm,
jpayne@69 655 Bytef *dictionary,
jpayne@69 656 uInt *dictLength));
jpayne@69 657 /*
jpayne@69 658 Returns the sliding dictionary being maintained by deflate. dictLength is
jpayne@69 659 set to the number of bytes in the dictionary, and that many bytes are copied
jpayne@69 660 to dictionary. dictionary must have enough space, where 32768 bytes is
jpayne@69 661 always enough. If deflateGetDictionary() is called with dictionary equal to
jpayne@69 662 Z_NULL, then only the dictionary length is returned, and nothing is copied.
jpayne@69 663 Similarly, if dictLength is Z_NULL, then it is not set.
jpayne@69 664
jpayne@69 665 deflateGetDictionary() may return a length less than the window size, even
jpayne@69 666 when more than the window size in input has been provided. It may return up
jpayne@69 667 to 258 bytes less in that case, due to how zlib's implementation of deflate
jpayne@69 668 manages the sliding window and lookahead for matches, where matches can be
jpayne@69 669 up to 258 bytes long. If the application needs the last window-size bytes of
jpayne@69 670 input, then that would need to be saved by the application outside of zlib.
jpayne@69 671
jpayne@69 672 deflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
jpayne@69 673 stream state is inconsistent.
jpayne@69 674 */
jpayne@69 675
jpayne@69 676 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
jpayne@69 677 z_streamp source));
jpayne@69 678 /*
jpayne@69 679 Sets the destination stream as a complete copy of the source stream.
jpayne@69 680
jpayne@69 681 This function can be useful when several compression strategies will be
jpayne@69 682 tried, for example when there are several ways of pre-processing the input
jpayne@69 683 data with a filter. The streams that will be discarded should then be freed
jpayne@69 684 by calling deflateEnd. Note that deflateCopy duplicates the internal
jpayne@69 685 compression state which can be quite large, so this strategy is slow and can
jpayne@69 686 consume lots of memory.
jpayne@69 687
jpayne@69 688 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
jpayne@69 689 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
jpayne@69 690 (such as zalloc being Z_NULL). msg is left unchanged in both source and
jpayne@69 691 destination.
jpayne@69 692 */
jpayne@69 693
jpayne@69 694 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
jpayne@69 695 /*
jpayne@69 696 This function is equivalent to deflateEnd followed by deflateInit, but
jpayne@69 697 does not free and reallocate the internal compression state. The stream
jpayne@69 698 will leave the compression level and any other attributes that may have been
jpayne@69 699 set unchanged.
jpayne@69 700
jpayne@69 701 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 702 stream state was inconsistent (such as zalloc or state being Z_NULL).
jpayne@69 703 */
jpayne@69 704
jpayne@69 705 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
jpayne@69 706 int level,
jpayne@69 707 int strategy));
jpayne@69 708 /*
jpayne@69 709 Dynamically update the compression level and compression strategy. The
jpayne@69 710 interpretation of level and strategy is as in deflateInit2(). This can be
jpayne@69 711 used to switch between compression and straight copy of the input data, or
jpayne@69 712 to switch to a different kind of input data requiring a different strategy.
jpayne@69 713 If the compression approach (which is a function of the level) or the
jpayne@69 714 strategy is changed, and if there have been any deflate() calls since the
jpayne@69 715 state was initialized or reset, then the input available so far is
jpayne@69 716 compressed with the old level and strategy using deflate(strm, Z_BLOCK).
jpayne@69 717 There are three approaches for the compression levels 0, 1..3, and 4..9
jpayne@69 718 respectively. The new level and strategy will take effect at the next call
jpayne@69 719 of deflate().
jpayne@69 720
jpayne@69 721 If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does
jpayne@69 722 not have enough output space to complete, then the parameter change will not
jpayne@69 723 take effect. In this case, deflateParams() can be called again with the
jpayne@69 724 same parameters and more output space to try again.
jpayne@69 725
jpayne@69 726 In order to assure a change in the parameters on the first try, the
jpayne@69 727 deflate stream should be flushed using deflate() with Z_BLOCK or other flush
jpayne@69 728 request until strm.avail_out is not zero, before calling deflateParams().
jpayne@69 729 Then no more input data should be provided before the deflateParams() call.
jpayne@69 730 If this is done, the old level and strategy will be applied to the data
jpayne@69 731 compressed before deflateParams(), and the new level and strategy will be
jpayne@69 732 applied to the the data compressed after deflateParams().
jpayne@69 733
jpayne@69 734 deflateParams returns Z_OK on success, Z_STREAM_ERROR if the source stream
jpayne@69 735 state was inconsistent or if a parameter was invalid, or Z_BUF_ERROR if
jpayne@69 736 there was not enough output space to complete the compression of the
jpayne@69 737 available input data before a change in the strategy or approach. Note that
jpayne@69 738 in the case of a Z_BUF_ERROR, the parameters are not changed. A return
jpayne@69 739 value of Z_BUF_ERROR is not fatal, in which case deflateParams() can be
jpayne@69 740 retried with more output space.
jpayne@69 741 */
jpayne@69 742
jpayne@69 743 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
jpayne@69 744 int good_length,
jpayne@69 745 int max_lazy,
jpayne@69 746 int nice_length,
jpayne@69 747 int max_chain));
jpayne@69 748 /*
jpayne@69 749 Fine tune deflate's internal compression parameters. This should only be
jpayne@69 750 used by someone who understands the algorithm used by zlib's deflate for
jpayne@69 751 searching for the best matching string, and even then only by the most
jpayne@69 752 fanatic optimizer trying to squeeze out the last compressed bit for their
jpayne@69 753 specific input data. Read the deflate.c source code for the meaning of the
jpayne@69 754 max_lazy, good_length, nice_length, and max_chain parameters.
jpayne@69 755
jpayne@69 756 deflateTune() can be called after deflateInit() or deflateInit2(), and
jpayne@69 757 returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
jpayne@69 758 */
jpayne@69 759
jpayne@69 760 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
jpayne@69 761 uLong sourceLen));
jpayne@69 762 /*
jpayne@69 763 deflateBound() returns an upper bound on the compressed size after
jpayne@69 764 deflation of sourceLen bytes. It must be called after deflateInit() or
jpayne@69 765 deflateInit2(), and after deflateSetHeader(), if used. This would be used
jpayne@69 766 to allocate an output buffer for deflation in a single pass, and so would be
jpayne@69 767 called before deflate(). If that first deflate() call is provided the
jpayne@69 768 sourceLen input bytes, an output buffer allocated to the size returned by
jpayne@69 769 deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
jpayne@69 770 to return Z_STREAM_END. Note that it is possible for the compressed size to
jpayne@69 771 be larger than the value returned by deflateBound() if flush options other
jpayne@69 772 than Z_FINISH or Z_NO_FLUSH are used.
jpayne@69 773 */
jpayne@69 774
jpayne@69 775 ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
jpayne@69 776 unsigned *pending,
jpayne@69 777 int *bits));
jpayne@69 778 /*
jpayne@69 779 deflatePending() returns the number of bytes and bits of output that have
jpayne@69 780 been generated, but not yet provided in the available output. The bytes not
jpayne@69 781 provided would be due to the available output space having being consumed.
jpayne@69 782 The number of bits of output not provided are between 0 and 7, where they
jpayne@69 783 await more bits to join them in order to fill out a full byte. If pending
jpayne@69 784 or bits are Z_NULL, then those values are not set.
jpayne@69 785
jpayne@69 786 deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 787 stream state was inconsistent.
jpayne@69 788 */
jpayne@69 789
jpayne@69 790 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
jpayne@69 791 int bits,
jpayne@69 792 int value));
jpayne@69 793 /*
jpayne@69 794 deflatePrime() inserts bits in the deflate output stream. The intent
jpayne@69 795 is that this function is used to start off the deflate output with the bits
jpayne@69 796 leftover from a previous deflate stream when appending to it. As such, this
jpayne@69 797 function can only be used for raw deflate, and must be used before the first
jpayne@69 798 deflate() call after a deflateInit2() or deflateReset(). bits must be less
jpayne@69 799 than or equal to 16, and that many of the least significant bits of value
jpayne@69 800 will be inserted in the output.
jpayne@69 801
jpayne@69 802 deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
jpayne@69 803 room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
jpayne@69 804 source stream state was inconsistent.
jpayne@69 805 */
jpayne@69 806
jpayne@69 807 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
jpayne@69 808 gz_headerp head));
jpayne@69 809 /*
jpayne@69 810 deflateSetHeader() provides gzip header information for when a gzip
jpayne@69 811 stream is requested by deflateInit2(). deflateSetHeader() may be called
jpayne@69 812 after deflateInit2() or deflateReset() and before the first call of
jpayne@69 813 deflate(). The text, time, os, extra field, name, and comment information
jpayne@69 814 in the provided gz_header structure are written to the gzip header (xflag is
jpayne@69 815 ignored -- the extra flags are set according to the compression level). The
jpayne@69 816 caller must assure that, if not Z_NULL, name and comment are terminated with
jpayne@69 817 a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
jpayne@69 818 available there. If hcrc is true, a gzip header crc is included. Note that
jpayne@69 819 the current versions of the command-line version of gzip (up through version
jpayne@69 820 1.3.x) do not support header crc's, and will report that it is a "multi-part
jpayne@69 821 gzip file" and give up.
jpayne@69 822
jpayne@69 823 If deflateSetHeader is not used, the default gzip header has text false,
jpayne@69 824 the time set to zero, and os set to 255, with no extra, name, or comment
jpayne@69 825 fields. The gzip header is returned to the default state by deflateReset().
jpayne@69 826
jpayne@69 827 deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 828 stream state was inconsistent.
jpayne@69 829 */
jpayne@69 830
jpayne@69 831 /*
jpayne@69 832 ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
jpayne@69 833 int windowBits));
jpayne@69 834
jpayne@69 835 This is another version of inflateInit with an extra parameter. The
jpayne@69 836 fields next_in, avail_in, zalloc, zfree and opaque must be initialized
jpayne@69 837 before by the caller.
jpayne@69 838
jpayne@69 839 The windowBits parameter is the base two logarithm of the maximum window
jpayne@69 840 size (the size of the history buffer). It should be in the range 8..15 for
jpayne@69 841 this version of the library. The default value is 15 if inflateInit is used
jpayne@69 842 instead. windowBits must be greater than or equal to the windowBits value
jpayne@69 843 provided to deflateInit2() while compressing, or it must be equal to 15 if
jpayne@69 844 deflateInit2() was not used. If a compressed stream with a larger window
jpayne@69 845 size is given as input, inflate() will return with the error code
jpayne@69 846 Z_DATA_ERROR instead of trying to allocate a larger window.
jpayne@69 847
jpayne@69 848 windowBits can also be zero to request that inflate use the window size in
jpayne@69 849 the zlib header of the compressed stream.
jpayne@69 850
jpayne@69 851 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
jpayne@69 852 determines the window size. inflate() will then process raw deflate data,
jpayne@69 853 not looking for a zlib or gzip header, not generating a check value, and not
jpayne@69 854 looking for any check values for comparison at the end of the stream. This
jpayne@69 855 is for use with other formats that use the deflate compressed data format
jpayne@69 856 such as zip. Those formats provide their own check values. If a custom
jpayne@69 857 format is developed using the raw deflate format for compressed data, it is
jpayne@69 858 recommended that a check value such as an Adler-32 or a CRC-32 be applied to
jpayne@69 859 the uncompressed data as is done in the zlib, gzip, and zip formats. For
jpayne@69 860 most applications, the zlib format should be used as is. Note that comments
jpayne@69 861 above on the use in deflateInit2() applies to the magnitude of windowBits.
jpayne@69 862
jpayne@69 863 windowBits can also be greater than 15 for optional gzip decoding. Add
jpayne@69 864 32 to windowBits to enable zlib and gzip decoding with automatic header
jpayne@69 865 detection, or add 16 to decode only the gzip format (the zlib format will
jpayne@69 866 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
jpayne@69 867 CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see
jpayne@69 868 below), inflate() will *not* automatically decode concatenated gzip members.
jpayne@69 869 inflate() will return Z_STREAM_END at the end of the gzip member. The state
jpayne@69 870 would need to be reset to continue decoding a subsequent gzip member. This
jpayne@69 871 *must* be done if there is more data after a gzip member, in order for the
jpayne@69 872 decompression to be compliant with the gzip standard (RFC 1952).
jpayne@69 873
jpayne@69 874 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
jpayne@69 875 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
jpayne@69 876 version assumed by the caller, or Z_STREAM_ERROR if the parameters are
jpayne@69 877 invalid, such as a null pointer to the structure. msg is set to null if
jpayne@69 878 there is no error message. inflateInit2 does not perform any decompression
jpayne@69 879 apart from possibly reading the zlib header if present: actual decompression
jpayne@69 880 will be done by inflate(). (So next_in and avail_in may be modified, but
jpayne@69 881 next_out and avail_out are unused and unchanged.) The current implementation
jpayne@69 882 of inflateInit2() does not process any header information -- that is
jpayne@69 883 deferred until inflate() is called.
jpayne@69 884 */
jpayne@69 885
jpayne@69 886 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
jpayne@69 887 const Bytef *dictionary,
jpayne@69 888 uInt dictLength));
jpayne@69 889 /*
jpayne@69 890 Initializes the decompression dictionary from the given uncompressed byte
jpayne@69 891 sequence. This function must be called immediately after a call of inflate,
jpayne@69 892 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
jpayne@69 893 can be determined from the Adler-32 value returned by that call of inflate.
jpayne@69 894 The compressor and decompressor must use exactly the same dictionary (see
jpayne@69 895 deflateSetDictionary). For raw inflate, this function can be called at any
jpayne@69 896 time to set the dictionary. If the provided dictionary is smaller than the
jpayne@69 897 window and there is already data in the window, then the provided dictionary
jpayne@69 898 will amend what's there. The application must insure that the dictionary
jpayne@69 899 that was used for compression is provided.
jpayne@69 900
jpayne@69 901 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
jpayne@69 902 parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
jpayne@69 903 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
jpayne@69 904 expected one (incorrect Adler-32 value). inflateSetDictionary does not
jpayne@69 905 perform any decompression: this will be done by subsequent calls of
jpayne@69 906 inflate().
jpayne@69 907 */
jpayne@69 908
jpayne@69 909 ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
jpayne@69 910 Bytef *dictionary,
jpayne@69 911 uInt *dictLength));
jpayne@69 912 /*
jpayne@69 913 Returns the sliding dictionary being maintained by inflate. dictLength is
jpayne@69 914 set to the number of bytes in the dictionary, and that many bytes are copied
jpayne@69 915 to dictionary. dictionary must have enough space, where 32768 bytes is
jpayne@69 916 always enough. If inflateGetDictionary() is called with dictionary equal to
jpayne@69 917 Z_NULL, then only the dictionary length is returned, and nothing is copied.
jpayne@69 918 Similarly, if dictLength is Z_NULL, then it is not set.
jpayne@69 919
jpayne@69 920 inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
jpayne@69 921 stream state is inconsistent.
jpayne@69 922 */
jpayne@69 923
jpayne@69 924 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
jpayne@69 925 /*
jpayne@69 926 Skips invalid compressed data until a possible full flush point (see above
jpayne@69 927 for the description of deflate with Z_FULL_FLUSH) can be found, or until all
jpayne@69 928 available input is skipped. No output is provided.
jpayne@69 929
jpayne@69 930 inflateSync searches for a 00 00 FF FF pattern in the compressed data.
jpayne@69 931 All full flush points have this pattern, but not all occurrences of this
jpayne@69 932 pattern are full flush points.
jpayne@69 933
jpayne@69 934 inflateSync returns Z_OK if a possible full flush point has been found,
jpayne@69 935 Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
jpayne@69 936 has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
jpayne@69 937 In the success case, the application may save the current current value of
jpayne@69 938 total_in which indicates where valid compressed data was found. In the
jpayne@69 939 error case, the application may repeatedly call inflateSync, providing more
jpayne@69 940 input each time, until success or end of the input data.
jpayne@69 941 */
jpayne@69 942
jpayne@69 943 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
jpayne@69 944 z_streamp source));
jpayne@69 945 /*
jpayne@69 946 Sets the destination stream as a complete copy of the source stream.
jpayne@69 947
jpayne@69 948 This function can be useful when randomly accessing a large stream. The
jpayne@69 949 first pass through the stream can periodically record the inflate state,
jpayne@69 950 allowing restarting inflate at those points when randomly accessing the
jpayne@69 951 stream.
jpayne@69 952
jpayne@69 953 inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
jpayne@69 954 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
jpayne@69 955 (such as zalloc being Z_NULL). msg is left unchanged in both source and
jpayne@69 956 destination.
jpayne@69 957 */
jpayne@69 958
jpayne@69 959 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
jpayne@69 960 /*
jpayne@69 961 This function is equivalent to inflateEnd followed by inflateInit,
jpayne@69 962 but does not free and reallocate the internal decompression state. The
jpayne@69 963 stream will keep attributes that may have been set by inflateInit2.
jpayne@69 964
jpayne@69 965 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 966 stream state was inconsistent (such as zalloc or state being Z_NULL).
jpayne@69 967 */
jpayne@69 968
jpayne@69 969 ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
jpayne@69 970 int windowBits));
jpayne@69 971 /*
jpayne@69 972 This function is the same as inflateReset, but it also permits changing
jpayne@69 973 the wrap and window size requests. The windowBits parameter is interpreted
jpayne@69 974 the same as it is for inflateInit2. If the window size is changed, then the
jpayne@69 975 memory allocated for the window is freed, and the window will be reallocated
jpayne@69 976 by inflate() if needed.
jpayne@69 977
jpayne@69 978 inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 979 stream state was inconsistent (such as zalloc or state being Z_NULL), or if
jpayne@69 980 the windowBits parameter is invalid.
jpayne@69 981 */
jpayne@69 982
jpayne@69 983 ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
jpayne@69 984 int bits,
jpayne@69 985 int value));
jpayne@69 986 /*
jpayne@69 987 This function inserts bits in the inflate input stream. The intent is
jpayne@69 988 that this function is used to start inflating at a bit position in the
jpayne@69 989 middle of a byte. The provided bits will be used before any bytes are used
jpayne@69 990 from next_in. This function should only be used with raw inflate, and
jpayne@69 991 should be used before the first inflate() call after inflateInit2() or
jpayne@69 992 inflateReset(). bits must be less than or equal to 16, and that many of the
jpayne@69 993 least significant bits of value will be inserted in the input.
jpayne@69 994
jpayne@69 995 If bits is negative, then the input stream bit buffer is emptied. Then
jpayne@69 996 inflatePrime() can be called again to put bits in the buffer. This is used
jpayne@69 997 to clear out bits leftover after feeding inflate a block description prior
jpayne@69 998 to feeding inflate codes.
jpayne@69 999
jpayne@69 1000 inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 1001 stream state was inconsistent.
jpayne@69 1002 */
jpayne@69 1003
jpayne@69 1004 ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
jpayne@69 1005 /*
jpayne@69 1006 This function returns two values, one in the lower 16 bits of the return
jpayne@69 1007 value, and the other in the remaining upper bits, obtained by shifting the
jpayne@69 1008 return value down 16 bits. If the upper value is -1 and the lower value is
jpayne@69 1009 zero, then inflate() is currently decoding information outside of a block.
jpayne@69 1010 If the upper value is -1 and the lower value is non-zero, then inflate is in
jpayne@69 1011 the middle of a stored block, with the lower value equaling the number of
jpayne@69 1012 bytes from the input remaining to copy. If the upper value is not -1, then
jpayne@69 1013 it is the number of bits back from the current bit position in the input of
jpayne@69 1014 the code (literal or length/distance pair) currently being processed. In
jpayne@69 1015 that case the lower value is the number of bytes already emitted for that
jpayne@69 1016 code.
jpayne@69 1017
jpayne@69 1018 A code is being processed if inflate is waiting for more input to complete
jpayne@69 1019 decoding of the code, or if it has completed decoding but is waiting for
jpayne@69 1020 more output space to write the literal or match data.
jpayne@69 1021
jpayne@69 1022 inflateMark() is used to mark locations in the input data for random
jpayne@69 1023 access, which may be at bit positions, and to note those cases where the
jpayne@69 1024 output of a code may span boundaries of random access blocks. The current
jpayne@69 1025 location in the input stream can be determined from avail_in and data_type
jpayne@69 1026 as noted in the description for the Z_BLOCK flush parameter for inflate.
jpayne@69 1027
jpayne@69 1028 inflateMark returns the value noted above, or -65536 if the provided
jpayne@69 1029 source stream state was inconsistent.
jpayne@69 1030 */
jpayne@69 1031
jpayne@69 1032 ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
jpayne@69 1033 gz_headerp head));
jpayne@69 1034 /*
jpayne@69 1035 inflateGetHeader() requests that gzip header information be stored in the
jpayne@69 1036 provided gz_header structure. inflateGetHeader() may be called after
jpayne@69 1037 inflateInit2() or inflateReset(), and before the first call of inflate().
jpayne@69 1038 As inflate() processes the gzip stream, head->done is zero until the header
jpayne@69 1039 is completed, at which time head->done is set to one. If a zlib stream is
jpayne@69 1040 being decoded, then head->done is set to -1 to indicate that there will be
jpayne@69 1041 no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be
jpayne@69 1042 used to force inflate() to return immediately after header processing is
jpayne@69 1043 complete and before any actual data is decompressed.
jpayne@69 1044
jpayne@69 1045 The text, time, xflags, and os fields are filled in with the gzip header
jpayne@69 1046 contents. hcrc is set to true if there is a header CRC. (The header CRC
jpayne@69 1047 was valid if done is set to one.) If extra is not Z_NULL, then extra_max
jpayne@69 1048 contains the maximum number of bytes to write to extra. Once done is true,
jpayne@69 1049 extra_len contains the actual extra field length, and extra contains the
jpayne@69 1050 extra field, or that field truncated if extra_max is less than extra_len.
jpayne@69 1051 If name is not Z_NULL, then up to name_max characters are written there,
jpayne@69 1052 terminated with a zero unless the length is greater than name_max. If
jpayne@69 1053 comment is not Z_NULL, then up to comm_max characters are written there,
jpayne@69 1054 terminated with a zero unless the length is greater than comm_max. When any
jpayne@69 1055 of extra, name, or comment are not Z_NULL and the respective field is not
jpayne@69 1056 present in the header, then that field is set to Z_NULL to signal its
jpayne@69 1057 absence. This allows the use of deflateSetHeader() with the returned
jpayne@69 1058 structure to duplicate the header. However if those fields are set to
jpayne@69 1059 allocated memory, then the application will need to save those pointers
jpayne@69 1060 elsewhere so that they can be eventually freed.
jpayne@69 1061
jpayne@69 1062 If inflateGetHeader is not used, then the header information is simply
jpayne@69 1063 discarded. The header is always checked for validity, including the header
jpayne@69 1064 CRC if present. inflateReset() will reset the process to discard the header
jpayne@69 1065 information. The application would need to call inflateGetHeader() again to
jpayne@69 1066 retrieve the header from the next gzip stream.
jpayne@69 1067
jpayne@69 1068 inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
jpayne@69 1069 stream state was inconsistent.
jpayne@69 1070 */
jpayne@69 1071
jpayne@69 1072 /*
jpayne@69 1073 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
jpayne@69 1074 unsigned char FAR *window));
jpayne@69 1075
jpayne@69 1076 Initialize the internal stream state for decompression using inflateBack()
jpayne@69 1077 calls. The fields zalloc, zfree and opaque in strm must be initialized
jpayne@69 1078 before the call. If zalloc and zfree are Z_NULL, then the default library-
jpayne@69 1079 derived memory allocation routines are used. windowBits is the base two
jpayne@69 1080 logarithm of the window size, in the range 8..15. window is a caller
jpayne@69 1081 supplied buffer of that size. Except for special applications where it is
jpayne@69 1082 assured that deflate was used with small window sizes, windowBits must be 15
jpayne@69 1083 and a 32K byte window must be supplied to be able to decompress general
jpayne@69 1084 deflate streams.
jpayne@69 1085
jpayne@69 1086 See inflateBack() for the usage of these routines.
jpayne@69 1087
jpayne@69 1088 inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
jpayne@69 1089 the parameters are invalid, Z_MEM_ERROR if the internal state could not be
jpayne@69 1090 allocated, or Z_VERSION_ERROR if the version of the library does not match
jpayne@69 1091 the version of the header file.
jpayne@69 1092 */
jpayne@69 1093
jpayne@69 1094 typedef unsigned (*in_func) OF((void FAR *,
jpayne@69 1095 z_const unsigned char FAR * FAR *));
jpayne@69 1096 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
jpayne@69 1097
jpayne@69 1098 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
jpayne@69 1099 in_func in, void FAR *in_desc,
jpayne@69 1100 out_func out, void FAR *out_desc));
jpayne@69 1101 /*
jpayne@69 1102 inflateBack() does a raw inflate with a single call using a call-back
jpayne@69 1103 interface for input and output. This is potentially more efficient than
jpayne@69 1104 inflate() for file i/o applications, in that it avoids copying between the
jpayne@69 1105 output and the sliding window by simply making the window itself the output
jpayne@69 1106 buffer. inflate() can be faster on modern CPUs when used with large
jpayne@69 1107 buffers. inflateBack() trusts the application to not change the output
jpayne@69 1108 buffer passed by the output function, at least until inflateBack() returns.
jpayne@69 1109
jpayne@69 1110 inflateBackInit() must be called first to allocate the internal state
jpayne@69 1111 and to initialize the state with the user-provided window buffer.
jpayne@69 1112 inflateBack() may then be used multiple times to inflate a complete, raw
jpayne@69 1113 deflate stream with each call. inflateBackEnd() is then called to free the
jpayne@69 1114 allocated state.
jpayne@69 1115
jpayne@69 1116 A raw deflate stream is one with no zlib or gzip header or trailer.
jpayne@69 1117 This routine would normally be used in a utility that reads zip or gzip
jpayne@69 1118 files and writes out uncompressed files. The utility would decode the
jpayne@69 1119 header and process the trailer on its own, hence this routine expects only
jpayne@69 1120 the raw deflate stream to decompress. This is different from the default
jpayne@69 1121 behavior of inflate(), which expects a zlib header and trailer around the
jpayne@69 1122 deflate stream.
jpayne@69 1123
jpayne@69 1124 inflateBack() uses two subroutines supplied by the caller that are then
jpayne@69 1125 called by inflateBack() for input and output. inflateBack() calls those
jpayne@69 1126 routines until it reads a complete deflate stream and writes out all of the
jpayne@69 1127 uncompressed data, or until it encounters an error. The function's
jpayne@69 1128 parameters and return types are defined above in the in_func and out_func
jpayne@69 1129 typedefs. inflateBack() will call in(in_desc, &buf) which should return the
jpayne@69 1130 number of bytes of provided input, and a pointer to that input in buf. If
jpayne@69 1131 there is no input available, in() must return zero -- buf is ignored in that
jpayne@69 1132 case -- and inflateBack() will return a buffer error. inflateBack() will
jpayne@69 1133 call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
jpayne@69 1134 out() should return zero on success, or non-zero on failure. If out()
jpayne@69 1135 returns non-zero, inflateBack() will return with an error. Neither in() nor
jpayne@69 1136 out() are permitted to change the contents of the window provided to
jpayne@69 1137 inflateBackInit(), which is also the buffer that out() uses to write from.
jpayne@69 1138 The length written by out() will be at most the window size. Any non-zero
jpayne@69 1139 amount of input may be provided by in().
jpayne@69 1140
jpayne@69 1141 For convenience, inflateBack() can be provided input on the first call by
jpayne@69 1142 setting strm->next_in and strm->avail_in. If that input is exhausted, then
jpayne@69 1143 in() will be called. Therefore strm->next_in must be initialized before
jpayne@69 1144 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
jpayne@69 1145 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
jpayne@69 1146 must also be initialized, and then if strm->avail_in is not zero, input will
jpayne@69 1147 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
jpayne@69 1148
jpayne@69 1149 The in_desc and out_desc parameters of inflateBack() is passed as the
jpayne@69 1150 first parameter of in() and out() respectively when they are called. These
jpayne@69 1151 descriptors can be optionally used to pass any information that the caller-
jpayne@69 1152 supplied in() and out() functions need to do their job.
jpayne@69 1153
jpayne@69 1154 On return, inflateBack() will set strm->next_in and strm->avail_in to
jpayne@69 1155 pass back any unused input that was provided by the last in() call. The
jpayne@69 1156 return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
jpayne@69 1157 if in() or out() returned an error, Z_DATA_ERROR if there was a format error
jpayne@69 1158 in the deflate stream (in which case strm->msg is set to indicate the nature
jpayne@69 1159 of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
jpayne@69 1160 In the case of Z_BUF_ERROR, an input or output error can be distinguished
jpayne@69 1161 using strm->next_in which will be Z_NULL only if in() returned an error. If
jpayne@69 1162 strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
jpayne@69 1163 non-zero. (in() will always be called before out(), so strm->next_in is
jpayne@69 1164 assured to be defined if out() returns non-zero.) Note that inflateBack()
jpayne@69 1165 cannot return Z_OK.
jpayne@69 1166 */
jpayne@69 1167
jpayne@69 1168 ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
jpayne@69 1169 /*
jpayne@69 1170 All memory allocated by inflateBackInit() is freed.
jpayne@69 1171
jpayne@69 1172 inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
jpayne@69 1173 state was inconsistent.
jpayne@69 1174 */
jpayne@69 1175
jpayne@69 1176 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
jpayne@69 1177 /* Return flags indicating compile-time options.
jpayne@69 1178
jpayne@69 1179 Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
jpayne@69 1180 1.0: size of uInt
jpayne@69 1181 3.2: size of uLong
jpayne@69 1182 5.4: size of voidpf (pointer)
jpayne@69 1183 7.6: size of z_off_t
jpayne@69 1184
jpayne@69 1185 Compiler, assembler, and debug options:
jpayne@69 1186 8: ZLIB_DEBUG
jpayne@69 1187 9: ASMV or ASMINF -- use ASM code
jpayne@69 1188 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
jpayne@69 1189 11: 0 (reserved)
jpayne@69 1190
jpayne@69 1191 One-time table building (smaller code, but not thread-safe if true):
jpayne@69 1192 12: BUILDFIXED -- build static block decoding tables when needed
jpayne@69 1193 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
jpayne@69 1194 14,15: 0 (reserved)
jpayne@69 1195
jpayne@69 1196 Library content (indicates missing functionality):
jpayne@69 1197 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
jpayne@69 1198 deflate code when not needed)
jpayne@69 1199 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
jpayne@69 1200 and decode gzip streams (to avoid linking crc code)
jpayne@69 1201 18-19: 0 (reserved)
jpayne@69 1202
jpayne@69 1203 Operation variations (changes in library functionality):
jpayne@69 1204 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
jpayne@69 1205 21: FASTEST -- deflate algorithm with only one, lowest compression level
jpayne@69 1206 22,23: 0 (reserved)
jpayne@69 1207
jpayne@69 1208 The sprintf variant used by gzprintf (zero is best):
jpayne@69 1209 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
jpayne@69 1210 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
jpayne@69 1211 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
jpayne@69 1212
jpayne@69 1213 Remainder:
jpayne@69 1214 27-31: 0 (reserved)
jpayne@69 1215 */
jpayne@69 1216
jpayne@69 1217 #ifndef Z_SOLO
jpayne@69 1218
jpayne@69 1219 /* utility functions */
jpayne@69 1220
jpayne@69 1221 /*
jpayne@69 1222 The following utility functions are implemented on top of the basic
jpayne@69 1223 stream-oriented functions. To simplify the interface, some default options
jpayne@69 1224 are assumed (compression level and memory usage, standard memory allocation
jpayne@69 1225 functions). The source code of these utility functions can be modified if
jpayne@69 1226 you need special options.
jpayne@69 1227 */
jpayne@69 1228
jpayne@69 1229 ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
jpayne@69 1230 const Bytef *source, uLong sourceLen));
jpayne@69 1231 /*
jpayne@69 1232 Compresses the source buffer into the destination buffer. sourceLen is
jpayne@69 1233 the byte length of the source buffer. Upon entry, destLen is the total size
jpayne@69 1234 of the destination buffer, which must be at least the value returned by
jpayne@69 1235 compressBound(sourceLen). Upon exit, destLen is the actual size of the
jpayne@69 1236 compressed data. compress() is equivalent to compress2() with a level
jpayne@69 1237 parameter of Z_DEFAULT_COMPRESSION.
jpayne@69 1238
jpayne@69 1239 compress returns Z_OK if success, Z_MEM_ERROR if there was not
jpayne@69 1240 enough memory, Z_BUF_ERROR if there was not enough room in the output
jpayne@69 1241 buffer.
jpayne@69 1242 */
jpayne@69 1243
jpayne@69 1244 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
jpayne@69 1245 const Bytef *source, uLong sourceLen,
jpayne@69 1246 int level));
jpayne@69 1247 /*
jpayne@69 1248 Compresses the source buffer into the destination buffer. The level
jpayne@69 1249 parameter has the same meaning as in deflateInit. sourceLen is the byte
jpayne@69 1250 length of the source buffer. Upon entry, destLen is the total size of the
jpayne@69 1251 destination buffer, which must be at least the value returned by
jpayne@69 1252 compressBound(sourceLen). Upon exit, destLen is the actual size of the
jpayne@69 1253 compressed data.
jpayne@69 1254
jpayne@69 1255 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
jpayne@69 1256 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
jpayne@69 1257 Z_STREAM_ERROR if the level parameter is invalid.
jpayne@69 1258 */
jpayne@69 1259
jpayne@69 1260 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
jpayne@69 1261 /*
jpayne@69 1262 compressBound() returns an upper bound on the compressed size after
jpayne@69 1263 compress() or compress2() on sourceLen bytes. It would be used before a
jpayne@69 1264 compress() or compress2() call to allocate the destination buffer.
jpayne@69 1265 */
jpayne@69 1266
jpayne@69 1267 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
jpayne@69 1268 const Bytef *source, uLong sourceLen));
jpayne@69 1269 /*
jpayne@69 1270 Decompresses the source buffer into the destination buffer. sourceLen is
jpayne@69 1271 the byte length of the source buffer. Upon entry, destLen is the total size
jpayne@69 1272 of the destination buffer, which must be large enough to hold the entire
jpayne@69 1273 uncompressed data. (The size of the uncompressed data must have been saved
jpayne@69 1274 previously by the compressor and transmitted to the decompressor by some
jpayne@69 1275 mechanism outside the scope of this compression library.) Upon exit, destLen
jpayne@69 1276 is the actual size of the uncompressed data.
jpayne@69 1277
jpayne@69 1278 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
jpayne@69 1279 enough memory, Z_BUF_ERROR if there was not enough room in the output
jpayne@69 1280 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In
jpayne@69 1281 the case where there is not enough room, uncompress() will fill the output
jpayne@69 1282 buffer with the uncompressed data up to that point.
jpayne@69 1283 */
jpayne@69 1284
jpayne@69 1285 ZEXTERN int ZEXPORT uncompress2 OF((Bytef *dest, uLongf *destLen,
jpayne@69 1286 const Bytef *source, uLong *sourceLen));
jpayne@69 1287 /*
jpayne@69 1288 Same as uncompress, except that sourceLen is a pointer, where the
jpayne@69 1289 length of the source is *sourceLen. On return, *sourceLen is the number of
jpayne@69 1290 source bytes consumed.
jpayne@69 1291 */
jpayne@69 1292
jpayne@69 1293 /* gzip file access functions */
jpayne@69 1294
jpayne@69 1295 /*
jpayne@69 1296 This library supports reading and writing files in gzip (.gz) format with
jpayne@69 1297 an interface similar to that of stdio, using the functions that start with
jpayne@69 1298 "gz". The gzip format is different from the zlib format. gzip is a gzip
jpayne@69 1299 wrapper, documented in RFC 1952, wrapped around a deflate stream.
jpayne@69 1300 */
jpayne@69 1301
jpayne@69 1302 typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */
jpayne@69 1303
jpayne@69 1304 /*
jpayne@69 1305 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
jpayne@69 1306
jpayne@69 1307 Open the gzip (.gz) file at path for reading and decompressing, or
jpayne@69 1308 compressing and writing. The mode parameter is as in fopen ("rb" or "wb")
jpayne@69 1309 but can also include a compression level ("wb9") or a strategy: 'f' for
jpayne@69 1310 filtered data as in "wb6f", 'h' for Huffman-only compression as in "wb1h",
jpayne@69 1311 'R' for run-length encoding as in "wb1R", or 'F' for fixed code compression
jpayne@69 1312 as in "wb9F". (See the description of deflateInit2 for more information
jpayne@69 1313 about the strategy parameter.) 'T' will request transparent writing or
jpayne@69 1314 appending with no compression and not using the gzip format.
jpayne@69 1315
jpayne@69 1316 "a" can be used instead of "w" to request that the gzip stream that will
jpayne@69 1317 be written be appended to the file. "+" will result in an error, since
jpayne@69 1318 reading and writing to the same gzip file is not supported. The addition of
jpayne@69 1319 "x" when writing will create the file exclusively, which fails if the file
jpayne@69 1320 already exists. On systems that support it, the addition of "e" when
jpayne@69 1321 reading or writing will set the flag to close the file on an execve() call.
jpayne@69 1322
jpayne@69 1323 These functions, as well as gzip, will read and decode a sequence of gzip
jpayne@69 1324 streams in a file. The append function of gzopen() can be used to create
jpayne@69 1325 such a file. (Also see gzflush() for another way to do this.) When
jpayne@69 1326 appending, gzopen does not test whether the file begins with a gzip stream,
jpayne@69 1327 nor does it look for the end of the gzip streams to begin appending. gzopen
jpayne@69 1328 will simply append a gzip stream to the existing file.
jpayne@69 1329
jpayne@69 1330 gzopen can be used to read a file which is not in gzip format; in this
jpayne@69 1331 case gzread will directly read from the file without decompression. When
jpayne@69 1332 reading, this will be detected automatically by looking for the magic two-
jpayne@69 1333 byte gzip header.
jpayne@69 1334
jpayne@69 1335 gzopen returns NULL if the file could not be opened, if there was
jpayne@69 1336 insufficient memory to allocate the gzFile state, or if an invalid mode was
jpayne@69 1337 specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
jpayne@69 1338 errno can be checked to determine if the reason gzopen failed was that the
jpayne@69 1339 file could not be opened.
jpayne@69 1340 */
jpayne@69 1341
jpayne@69 1342 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
jpayne@69 1343 /*
jpayne@69 1344 Associate a gzFile with the file descriptor fd. File descriptors are
jpayne@69 1345 obtained from calls like open, dup, creat, pipe or fileno (if the file has
jpayne@69 1346 been previously opened with fopen). The mode parameter is as in gzopen.
jpayne@69 1347
jpayne@69 1348 The next call of gzclose on the returned gzFile will also close the file
jpayne@69 1349 descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
jpayne@69 1350 fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
jpayne@69 1351 mode);. The duplicated descriptor should be saved to avoid a leak, since
jpayne@69 1352 gzdopen does not close fd if it fails. If you are using fileno() to get the
jpayne@69 1353 file descriptor from a FILE *, then you will have to use dup() to avoid
jpayne@69 1354 double-close()ing the file descriptor. Both gzclose() and fclose() will
jpayne@69 1355 close the associated file descriptor, so they need to have different file
jpayne@69 1356 descriptors.
jpayne@69 1357
jpayne@69 1358 gzdopen returns NULL if there was insufficient memory to allocate the
jpayne@69 1359 gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
jpayne@69 1360 provided, or '+' was provided), or if fd is -1. The file descriptor is not
jpayne@69 1361 used until the next gz* read, write, seek, or close operation, so gzdopen
jpayne@69 1362 will not detect if fd is invalid (unless fd is -1).
jpayne@69 1363 */
jpayne@69 1364
jpayne@69 1365 ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
jpayne@69 1366 /*
jpayne@69 1367 Set the internal buffer size used by this library's functions for file to
jpayne@69 1368 size. The default buffer size is 8192 bytes. This function must be called
jpayne@69 1369 after gzopen() or gzdopen(), and before any other calls that read or write
jpayne@69 1370 the file. The buffer memory allocation is always deferred to the first read
jpayne@69 1371 or write. Three times that size in buffer space is allocated. A larger
jpayne@69 1372 buffer size of, for example, 64K or 128K bytes will noticeably increase the
jpayne@69 1373 speed of decompression (reading).
jpayne@69 1374
jpayne@69 1375 The new buffer size also affects the maximum length for gzprintf().
jpayne@69 1376
jpayne@69 1377 gzbuffer() returns 0 on success, or -1 on failure, such as being called
jpayne@69 1378 too late.
jpayne@69 1379 */
jpayne@69 1380
jpayne@69 1381 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
jpayne@69 1382 /*
jpayne@69 1383 Dynamically update the compression level and strategy for file. See the
jpayne@69 1384 description of deflateInit2 for the meaning of these parameters. Previously
jpayne@69 1385 provided data is flushed before applying the parameter changes.
jpayne@69 1386
jpayne@69 1387 gzsetparams returns Z_OK if success, Z_STREAM_ERROR if the file was not
jpayne@69 1388 opened for writing, Z_ERRNO if there is an error writing the flushed data,
jpayne@69 1389 or Z_MEM_ERROR if there is a memory allocation error.
jpayne@69 1390 */
jpayne@69 1391
jpayne@69 1392 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
jpayne@69 1393 /*
jpayne@69 1394 Read and decompress up to len uncompressed bytes from file into buf. If
jpayne@69 1395 the input file is not in gzip format, gzread copies the given number of
jpayne@69 1396 bytes into the buffer directly from the file.
jpayne@69 1397
jpayne@69 1398 After reaching the end of a gzip stream in the input, gzread will continue
jpayne@69 1399 to read, looking for another gzip stream. Any number of gzip streams may be
jpayne@69 1400 concatenated in the input file, and will all be decompressed by gzread().
jpayne@69 1401 If something other than a gzip stream is encountered after a gzip stream,
jpayne@69 1402 that remaining trailing garbage is ignored (and no error is returned).
jpayne@69 1403
jpayne@69 1404 gzread can be used to read a gzip file that is being concurrently written.
jpayne@69 1405 Upon reaching the end of the input, gzread will return with the available
jpayne@69 1406 data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
jpayne@69 1407 gzclearerr can be used to clear the end of file indicator in order to permit
jpayne@69 1408 gzread to be tried again. Z_OK indicates that a gzip stream was completed
jpayne@69 1409 on the last gzread. Z_BUF_ERROR indicates that the input file ended in the
jpayne@69 1410 middle of a gzip stream. Note that gzread does not return -1 in the event
jpayne@69 1411 of an incomplete gzip stream. This error is deferred until gzclose(), which
jpayne@69 1412 will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
jpayne@69 1413 stream. Alternatively, gzerror can be used before gzclose to detect this
jpayne@69 1414 case.
jpayne@69 1415
jpayne@69 1416 gzread returns the number of uncompressed bytes actually read, less than
jpayne@69 1417 len for end of file, or -1 for error. If len is too large to fit in an int,
jpayne@69 1418 then nothing is read, -1 is returned, and the error state is set to
jpayne@69 1419 Z_STREAM_ERROR.
jpayne@69 1420 */
jpayne@69 1421
jpayne@69 1422 ZEXTERN z_size_t ZEXPORT gzfread OF((voidp buf, z_size_t size, z_size_t nitems,
jpayne@69 1423 gzFile file));
jpayne@69 1424 /*
jpayne@69 1425 Read and decompress up to nitems items of size size from file into buf,
jpayne@69 1426 otherwise operating as gzread() does. This duplicates the interface of
jpayne@69 1427 stdio's fread(), with size_t request and return types. If the library
jpayne@69 1428 defines size_t, then z_size_t is identical to size_t. If not, then z_size_t
jpayne@69 1429 is an unsigned integer type that can contain a pointer.
jpayne@69 1430
jpayne@69 1431 gzfread() returns the number of full items read of size size, or zero if
jpayne@69 1432 the end of the file was reached and a full item could not be read, or if
jpayne@69 1433 there was an error. gzerror() must be consulted if zero is returned in
jpayne@69 1434 order to determine if there was an error. If the multiplication of size and
jpayne@69 1435 nitems overflows, i.e. the product does not fit in a z_size_t, then nothing
jpayne@69 1436 is read, zero is returned, and the error state is set to Z_STREAM_ERROR.
jpayne@69 1437
jpayne@69 1438 In the event that the end of file is reached and only a partial item is
jpayne@69 1439 available at the end, i.e. the remaining uncompressed data length is not a
jpayne@69 1440 multiple of size, then the final partial item is nevertheless read into buf
jpayne@69 1441 and the end-of-file flag is set. The length of the partial item read is not
jpayne@69 1442 provided, but could be inferred from the result of gztell(). This behavior
jpayne@69 1443 is the same as the behavior of fread() implementations in common libraries,
jpayne@69 1444 but it prevents the direct use of gzfread() to read a concurrently written
jpayne@69 1445 file, resetting and retrying on end-of-file, when size is not 1.
jpayne@69 1446 */
jpayne@69 1447
jpayne@69 1448 ZEXTERN int ZEXPORT gzwrite OF((gzFile file, voidpc buf, unsigned len));
jpayne@69 1449 /*
jpayne@69 1450 Compress and write the len uncompressed bytes at buf to file. gzwrite
jpayne@69 1451 returns the number of uncompressed bytes written or 0 in case of error.
jpayne@69 1452 */
jpayne@69 1453
jpayne@69 1454 ZEXTERN z_size_t ZEXPORT gzfwrite OF((voidpc buf, z_size_t size,
jpayne@69 1455 z_size_t nitems, gzFile file));
jpayne@69 1456 /*
jpayne@69 1457 Compress and write nitems items of size size from buf to file, duplicating
jpayne@69 1458 the interface of stdio's fwrite(), with size_t request and return types. If
jpayne@69 1459 the library defines size_t, then z_size_t is identical to size_t. If not,
jpayne@69 1460 then z_size_t is an unsigned integer type that can contain a pointer.
jpayne@69 1461
jpayne@69 1462 gzfwrite() returns the number of full items written of size size, or zero
jpayne@69 1463 if there was an error. If the multiplication of size and nitems overflows,
jpayne@69 1464 i.e. the product does not fit in a z_size_t, then nothing is written, zero
jpayne@69 1465 is returned, and the error state is set to Z_STREAM_ERROR.
jpayne@69 1466 */
jpayne@69 1467
jpayne@69 1468 ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
jpayne@69 1469 /*
jpayne@69 1470 Convert, format, compress, and write the arguments (...) to file under
jpayne@69 1471 control of the string format, as in fprintf. gzprintf returns the number of
jpayne@69 1472 uncompressed bytes actually written, or a negative zlib error code in case
jpayne@69 1473 of error. The number of uncompressed bytes written is limited to 8191, or
jpayne@69 1474 one less than the buffer size given to gzbuffer(). The caller should assure
jpayne@69 1475 that this limit is not exceeded. If it is exceeded, then gzprintf() will
jpayne@69 1476 return an error (0) with nothing written. In this case, there may also be a
jpayne@69 1477 buffer overflow with unpredictable consequences, which is possible only if
jpayne@69 1478 zlib was compiled with the insecure functions sprintf() or vsprintf(),
jpayne@69 1479 because the secure snprintf() or vsnprintf() functions were not available.
jpayne@69 1480 This can be determined using zlibCompileFlags().
jpayne@69 1481 */
jpayne@69 1482
jpayne@69 1483 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
jpayne@69 1484 /*
jpayne@69 1485 Compress and write the given null-terminated string s to file, excluding
jpayne@69 1486 the terminating null character.
jpayne@69 1487
jpayne@69 1488 gzputs returns the number of characters written, or -1 in case of error.
jpayne@69 1489 */
jpayne@69 1490
jpayne@69 1491 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
jpayne@69 1492 /*
jpayne@69 1493 Read and decompress bytes from file into buf, until len-1 characters are
jpayne@69 1494 read, or until a newline character is read and transferred to buf, or an
jpayne@69 1495 end-of-file condition is encountered. If any characters are read or if len
jpayne@69 1496 is one, the string is terminated with a null character. If no characters
jpayne@69 1497 are read due to an end-of-file or len is less than one, then the buffer is
jpayne@69 1498 left untouched.
jpayne@69 1499
jpayne@69 1500 gzgets returns buf which is a null-terminated string, or it returns NULL
jpayne@69 1501 for end-of-file or in case of error. If there was an error, the contents at
jpayne@69 1502 buf are indeterminate.
jpayne@69 1503 */
jpayne@69 1504
jpayne@69 1505 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
jpayne@69 1506 /*
jpayne@69 1507 Compress and write c, converted to an unsigned char, into file. gzputc
jpayne@69 1508 returns the value that was written, or -1 in case of error.
jpayne@69 1509 */
jpayne@69 1510
jpayne@69 1511 ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
jpayne@69 1512 /*
jpayne@69 1513 Read and decompress one byte from file. gzgetc returns this byte or -1
jpayne@69 1514 in case of end of file or error. This is implemented as a macro for speed.
jpayne@69 1515 As such, it does not do all of the checking the other functions do. I.e.
jpayne@69 1516 it does not check to see if file is NULL, nor whether the structure file
jpayne@69 1517 points to has been clobbered or not.
jpayne@69 1518 */
jpayne@69 1519
jpayne@69 1520 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
jpayne@69 1521 /*
jpayne@69 1522 Push c back onto the stream for file to be read as the first character on
jpayne@69 1523 the next read. At least one character of push-back is always allowed.
jpayne@69 1524 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
jpayne@69 1525 fail if c is -1, and may fail if a character has been pushed but not read
jpayne@69 1526 yet. If gzungetc is used immediately after gzopen or gzdopen, at least the
jpayne@69 1527 output buffer size of pushed characters is allowed. (See gzbuffer above.)
jpayne@69 1528 The pushed character will be discarded if the stream is repositioned with
jpayne@69 1529 gzseek() or gzrewind().
jpayne@69 1530 */
jpayne@69 1531
jpayne@69 1532 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
jpayne@69 1533 /*
jpayne@69 1534 Flush all pending output to file. The parameter flush is as in the
jpayne@69 1535 deflate() function. The return value is the zlib error number (see function
jpayne@69 1536 gzerror below). gzflush is only permitted when writing.
jpayne@69 1537
jpayne@69 1538 If the flush parameter is Z_FINISH, the remaining data is written and the
jpayne@69 1539 gzip stream is completed in the output. If gzwrite() is called again, a new
jpayne@69 1540 gzip stream will be started in the output. gzread() is able to read such
jpayne@69 1541 concatenated gzip streams.
jpayne@69 1542
jpayne@69 1543 gzflush should be called only when strictly necessary because it will
jpayne@69 1544 degrade compression if called too often.
jpayne@69 1545 */
jpayne@69 1546
jpayne@69 1547 /*
jpayne@69 1548 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
jpayne@69 1549 z_off_t offset, int whence));
jpayne@69 1550
jpayne@69 1551 Set the starting position to offset relative to whence for the next gzread
jpayne@69 1552 or gzwrite on file. The offset represents a number of bytes in the
jpayne@69 1553 uncompressed data stream. The whence parameter is defined as in lseek(2);
jpayne@69 1554 the value SEEK_END is not supported.
jpayne@69 1555
jpayne@69 1556 If the file is opened for reading, this function is emulated but can be
jpayne@69 1557 extremely slow. If the file is opened for writing, only forward seeks are
jpayne@69 1558 supported; gzseek then compresses a sequence of zeroes up to the new
jpayne@69 1559 starting position.
jpayne@69 1560
jpayne@69 1561 gzseek returns the resulting offset location as measured in bytes from
jpayne@69 1562 the beginning of the uncompressed stream, or -1 in case of error, in
jpayne@69 1563 particular if the file is opened for writing and the new starting position
jpayne@69 1564 would be before the current position.
jpayne@69 1565 */
jpayne@69 1566
jpayne@69 1567 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
jpayne@69 1568 /*
jpayne@69 1569 Rewind file. This function is supported only for reading.
jpayne@69 1570
jpayne@69 1571 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET).
jpayne@69 1572 */
jpayne@69 1573
jpayne@69 1574 /*
jpayne@69 1575 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
jpayne@69 1576
jpayne@69 1577 Return the starting position for the next gzread or gzwrite on file.
jpayne@69 1578 This position represents a number of bytes in the uncompressed data stream,
jpayne@69 1579 and is zero when starting, even if appending or reading a gzip stream from
jpayne@69 1580 the middle of a file using gzdopen().
jpayne@69 1581
jpayne@69 1582 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
jpayne@69 1583 */
jpayne@69 1584
jpayne@69 1585 /*
jpayne@69 1586 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));
jpayne@69 1587
jpayne@69 1588 Return the current compressed (actual) read or write offset of file. This
jpayne@69 1589 offset includes the count of bytes that precede the gzip stream, for example
jpayne@69 1590 when appending or when using gzdopen() for reading. When reading, the
jpayne@69 1591 offset does not include as yet unused buffered input. This information can
jpayne@69 1592 be used for a progress indicator. On error, gzoffset() returns -1.
jpayne@69 1593 */
jpayne@69 1594
jpayne@69 1595 ZEXTERN int ZEXPORT gzeof OF((gzFile file));
jpayne@69 1596 /*
jpayne@69 1597 Return true (1) if the end-of-file indicator for file has been set while
jpayne@69 1598 reading, false (0) otherwise. Note that the end-of-file indicator is set
jpayne@69 1599 only if the read tried to go past the end of the input, but came up short.
jpayne@69 1600 Therefore, just like feof(), gzeof() may return false even if there is no
jpayne@69 1601 more data to read, in the event that the last read request was for the exact
jpayne@69 1602 number of bytes remaining in the input file. This will happen if the input
jpayne@69 1603 file size is an exact multiple of the buffer size.
jpayne@69 1604
jpayne@69 1605 If gzeof() returns true, then the read functions will return no more data,
jpayne@69 1606 unless the end-of-file indicator is reset by gzclearerr() and the input file
jpayne@69 1607 has grown since the previous end of file was detected.
jpayne@69 1608 */
jpayne@69 1609
jpayne@69 1610 ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
jpayne@69 1611 /*
jpayne@69 1612 Return true (1) if file is being copied directly while reading, or false
jpayne@69 1613 (0) if file is a gzip stream being decompressed.
jpayne@69 1614
jpayne@69 1615 If the input file is empty, gzdirect() will return true, since the input
jpayne@69 1616 does not contain a gzip stream.
jpayne@69 1617
jpayne@69 1618 If gzdirect() is used immediately after gzopen() or gzdopen() it will
jpayne@69 1619 cause buffers to be allocated to allow reading the file to determine if it
jpayne@69 1620 is a gzip file. Therefore if gzbuffer() is used, it should be called before
jpayne@69 1621 gzdirect().
jpayne@69 1622
jpayne@69 1623 When writing, gzdirect() returns true (1) if transparent writing was
jpayne@69 1624 requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note:
jpayne@69 1625 gzdirect() is not needed when writing. Transparent writing must be
jpayne@69 1626 explicitly requested, so the application already knows the answer. When
jpayne@69 1627 linking statically, using gzdirect() will include all of the zlib code for
jpayne@69 1628 gzip file reading and decompression, which may not be desired.)
jpayne@69 1629 */
jpayne@69 1630
jpayne@69 1631 ZEXTERN int ZEXPORT gzclose OF((gzFile file));
jpayne@69 1632 /*
jpayne@69 1633 Flush all pending output for file, if necessary, close file and
jpayne@69 1634 deallocate the (de)compression state. Note that once file is closed, you
jpayne@69 1635 cannot call gzerror with file, since its structures have been deallocated.
jpayne@69 1636 gzclose must not be called more than once on the same file, just as free
jpayne@69 1637 must not be called more than once on the same allocation.
jpayne@69 1638
jpayne@69 1639 gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
jpayne@69 1640 file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
jpayne@69 1641 last read ended in the middle of a gzip stream, or Z_OK on success.
jpayne@69 1642 */
jpayne@69 1643
jpayne@69 1644 ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
jpayne@69 1645 ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
jpayne@69 1646 /*
jpayne@69 1647 Same as gzclose(), but gzclose_r() is only for use when reading, and
jpayne@69 1648 gzclose_w() is only for use when writing or appending. The advantage to
jpayne@69 1649 using these instead of gzclose() is that they avoid linking in zlib
jpayne@69 1650 compression or decompression code that is not used when only reading or only
jpayne@69 1651 writing respectively. If gzclose() is used, then both compression and
jpayne@69 1652 decompression code will be included the application when linking to a static
jpayne@69 1653 zlib library.
jpayne@69 1654 */
jpayne@69 1655
jpayne@69 1656 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
jpayne@69 1657 /*
jpayne@69 1658 Return the error message for the last error which occurred on file.
jpayne@69 1659 errnum is set to zlib error number. If an error occurred in the file system
jpayne@69 1660 and not in the compression library, errnum is set to Z_ERRNO and the
jpayne@69 1661 application may consult errno to get the exact error code.
jpayne@69 1662
jpayne@69 1663 The application must not modify the returned string. Future calls to
jpayne@69 1664 this function may invalidate the previously returned string. If file is
jpayne@69 1665 closed, then the string previously returned by gzerror will no longer be
jpayne@69 1666 available.
jpayne@69 1667
jpayne@69 1668 gzerror() should be used to distinguish errors from end-of-file for those
jpayne@69 1669 functions above that do not distinguish those cases in their return values.
jpayne@69 1670 */
jpayne@69 1671
jpayne@69 1672 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
jpayne@69 1673 /*
jpayne@69 1674 Clear the error and end-of-file flags for file. This is analogous to the
jpayne@69 1675 clearerr() function in stdio. This is useful for continuing to read a gzip
jpayne@69 1676 file that is being written concurrently.
jpayne@69 1677 */
jpayne@69 1678
jpayne@69 1679 #endif /* !Z_SOLO */
jpayne@69 1680
jpayne@69 1681 /* checksum functions */
jpayne@69 1682
jpayne@69 1683 /*
jpayne@69 1684 These functions are not related to compression but are exported
jpayne@69 1685 anyway because they might be useful in applications using the compression
jpayne@69 1686 library.
jpayne@69 1687 */
jpayne@69 1688
jpayne@69 1689 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
jpayne@69 1690 /*
jpayne@69 1691 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
jpayne@69 1692 return the updated checksum. An Adler-32 value is in the range of a 32-bit
jpayne@69 1693 unsigned integer. If buf is Z_NULL, this function returns the required
jpayne@69 1694 initial value for the checksum.
jpayne@69 1695
jpayne@69 1696 An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
jpayne@69 1697 much faster.
jpayne@69 1698
jpayne@69 1699 Usage example:
jpayne@69 1700
jpayne@69 1701 uLong adler = adler32(0L, Z_NULL, 0);
jpayne@69 1702
jpayne@69 1703 while (read_buffer(buffer, length) != EOF) {
jpayne@69 1704 adler = adler32(adler, buffer, length);
jpayne@69 1705 }
jpayne@69 1706 if (adler != original_adler) error();
jpayne@69 1707 */
jpayne@69 1708
jpayne@69 1709 ZEXTERN uLong ZEXPORT adler32_z OF((uLong adler, const Bytef *buf,
jpayne@69 1710 z_size_t len));
jpayne@69 1711 /*
jpayne@69 1712 Same as adler32(), but with a size_t length.
jpayne@69 1713 */
jpayne@69 1714
jpayne@69 1715 /*
jpayne@69 1716 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
jpayne@69 1717 z_off_t len2));
jpayne@69 1718
jpayne@69 1719 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
jpayne@69 1720 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
jpayne@69 1721 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
jpayne@69 1722 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note
jpayne@69 1723 that the z_off_t type (like off_t) is a signed integer. If len2 is
jpayne@69 1724 negative, the result has no meaning or utility.
jpayne@69 1725 */
jpayne@69 1726
jpayne@69 1727 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
jpayne@69 1728 /*
jpayne@69 1729 Update a running CRC-32 with the bytes buf[0..len-1] and return the
jpayne@69 1730 updated CRC-32. A CRC-32 value is in the range of a 32-bit unsigned integer.
jpayne@69 1731 If buf is Z_NULL, this function returns the required initial value for the
jpayne@69 1732 crc. Pre- and post-conditioning (one's complement) is performed within this
jpayne@69 1733 function so it shouldn't be done by the application.
jpayne@69 1734
jpayne@69 1735 Usage example:
jpayne@69 1736
jpayne@69 1737 uLong crc = crc32(0L, Z_NULL, 0);
jpayne@69 1738
jpayne@69 1739 while (read_buffer(buffer, length) != EOF) {
jpayne@69 1740 crc = crc32(crc, buffer, length);
jpayne@69 1741 }
jpayne@69 1742 if (crc != original_crc) error();
jpayne@69 1743 */
jpayne@69 1744
jpayne@69 1745 ZEXTERN uLong ZEXPORT crc32_z OF((uLong crc, const Bytef *buf,
jpayne@69 1746 z_size_t len));
jpayne@69 1747 /*
jpayne@69 1748 Same as crc32(), but with a size_t length.
jpayne@69 1749 */
jpayne@69 1750
jpayne@69 1751 /*
jpayne@69 1752 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
jpayne@69 1753
jpayne@69 1754 Combine two CRC-32 check values into one. For two sequences of bytes,
jpayne@69 1755 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
jpayne@69 1756 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
jpayne@69 1757 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
jpayne@69 1758 len2.
jpayne@69 1759 */
jpayne@69 1760
jpayne@69 1761 /*
jpayne@69 1762 ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t len2));
jpayne@69 1763
jpayne@69 1764 Return the operator corresponding to length len2, to be used with
jpayne@69 1765 crc32_combine_op().
jpayne@69 1766 */
jpayne@69 1767
jpayne@69 1768 ZEXTERN uLong ZEXPORT crc32_combine_op OF((uLong crc1, uLong crc2, uLong op));
jpayne@69 1769 /*
jpayne@69 1770 Give the same result as crc32_combine(), using op in place of len2. op is
jpayne@69 1771 is generated from len2 by crc32_combine_gen(). This will be faster than
jpayne@69 1772 crc32_combine() if the generated op is used more than once.
jpayne@69 1773 */
jpayne@69 1774
jpayne@69 1775
jpayne@69 1776 /* various hacks, don't look :) */
jpayne@69 1777
jpayne@69 1778 /* deflateInit and inflateInit are macros to allow checking the zlib version
jpayne@69 1779 * and the compiler's view of z_stream:
jpayne@69 1780 */
jpayne@69 1781 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
jpayne@69 1782 const char *version, int stream_size));
jpayne@69 1783 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
jpayne@69 1784 const char *version, int stream_size));
jpayne@69 1785 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
jpayne@69 1786 int windowBits, int memLevel,
jpayne@69 1787 int strategy, const char *version,
jpayne@69 1788 int stream_size));
jpayne@69 1789 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
jpayne@69 1790 const char *version, int stream_size));
jpayne@69 1791 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
jpayne@69 1792 unsigned char FAR *window,
jpayne@69 1793 const char *version,
jpayne@69 1794 int stream_size));
jpayne@69 1795 #ifdef Z_PREFIX_SET
jpayne@69 1796 # define z_deflateInit(strm, level) \
jpayne@69 1797 deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1798 # define z_inflateInit(strm) \
jpayne@69 1799 inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1800 # define z_deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
jpayne@69 1801 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
jpayne@69 1802 (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1803 # define z_inflateInit2(strm, windowBits) \
jpayne@69 1804 inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
jpayne@69 1805 (int)sizeof(z_stream))
jpayne@69 1806 # define z_inflateBackInit(strm, windowBits, window) \
jpayne@69 1807 inflateBackInit_((strm), (windowBits), (window), \
jpayne@69 1808 ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1809 #else
jpayne@69 1810 # define deflateInit(strm, level) \
jpayne@69 1811 deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1812 # define inflateInit(strm) \
jpayne@69 1813 inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1814 # define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
jpayne@69 1815 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
jpayne@69 1816 (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1817 # define inflateInit2(strm, windowBits) \
jpayne@69 1818 inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
jpayne@69 1819 (int)sizeof(z_stream))
jpayne@69 1820 # define inflateBackInit(strm, windowBits, window) \
jpayne@69 1821 inflateBackInit_((strm), (windowBits), (window), \
jpayne@69 1822 ZLIB_VERSION, (int)sizeof(z_stream))
jpayne@69 1823 #endif
jpayne@69 1824
jpayne@69 1825 #ifndef Z_SOLO
jpayne@69 1826
jpayne@69 1827 /* gzgetc() macro and its supporting function and exposed data structure. Note
jpayne@69 1828 * that the real internal state is much larger than the exposed structure.
jpayne@69 1829 * This abbreviated structure exposes just enough for the gzgetc() macro. The
jpayne@69 1830 * user should not mess with these exposed elements, since their names or
jpayne@69 1831 * behavior could change in the future, perhaps even capriciously. They can
jpayne@69 1832 * only be used by the gzgetc() macro. You have been warned.
jpayne@69 1833 */
jpayne@69 1834 struct gzFile_s {
jpayne@69 1835 unsigned have;
jpayne@69 1836 unsigned char *next;
jpayne@69 1837 z_off64_t pos;
jpayne@69 1838 };
jpayne@69 1839 ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file)); /* backward compatibility */
jpayne@69 1840 #ifdef Z_PREFIX_SET
jpayne@69 1841 # undef z_gzgetc
jpayne@69 1842 # define z_gzgetc(g) \
jpayne@69 1843 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
jpayne@69 1844 #else
jpayne@69 1845 # define gzgetc(g) \
jpayne@69 1846 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
jpayne@69 1847 #endif
jpayne@69 1848
jpayne@69 1849 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
jpayne@69 1850 * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
jpayne@69 1851 * both are true, the application gets the *64 functions, and the regular
jpayne@69 1852 * functions are changed to 64 bits) -- in case these are set on systems
jpayne@69 1853 * without large file support, _LFS64_LARGEFILE must also be true
jpayne@69 1854 */
jpayne@69 1855 #ifdef Z_LARGE64
jpayne@69 1856 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
jpayne@69 1857 ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
jpayne@69 1858 ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
jpayne@69 1859 ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
jpayne@69 1860 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
jpayne@69 1861 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
jpayne@69 1862 ZEXTERN uLong ZEXPORT crc32_combine_gen64 OF((z_off64_t));
jpayne@69 1863 #endif
jpayne@69 1864
jpayne@69 1865 #if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
jpayne@69 1866 # ifdef Z_PREFIX_SET
jpayne@69 1867 # define z_gzopen z_gzopen64
jpayne@69 1868 # define z_gzseek z_gzseek64
jpayne@69 1869 # define z_gztell z_gztell64
jpayne@69 1870 # define z_gzoffset z_gzoffset64
jpayne@69 1871 # define z_adler32_combine z_adler32_combine64
jpayne@69 1872 # define z_crc32_combine z_crc32_combine64
jpayne@69 1873 # define z_crc32_combine_gen z_crc32_combine_gen64
jpayne@69 1874 # else
jpayne@69 1875 # define gzopen gzopen64
jpayne@69 1876 # define gzseek gzseek64
jpayne@69 1877 # define gztell gztell64
jpayne@69 1878 # define gzoffset gzoffset64
jpayne@69 1879 # define adler32_combine adler32_combine64
jpayne@69 1880 # define crc32_combine crc32_combine64
jpayne@69 1881 # define crc32_combine_gen crc32_combine_gen64
jpayne@69 1882 # endif
jpayne@69 1883 # ifndef Z_LARGE64
jpayne@69 1884 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
jpayne@69 1885 ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
jpayne@69 1886 ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
jpayne@69 1887 ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
jpayne@69 1888 ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
jpayne@69 1889 ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
jpayne@69 1890 ZEXTERN uLong ZEXPORT crc32_combine_gen64 OF((z_off_t));
jpayne@69 1891 # endif
jpayne@69 1892 #else
jpayne@69 1893 ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
jpayne@69 1894 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
jpayne@69 1895 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
jpayne@69 1896 ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
jpayne@69 1897 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
jpayne@69 1898 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
jpayne@69 1899 ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t));
jpayne@69 1900 #endif
jpayne@69 1901
jpayne@69 1902 #else /* Z_SOLO */
jpayne@69 1903
jpayne@69 1904 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
jpayne@69 1905 ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
jpayne@69 1906 ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t));
jpayne@69 1907
jpayne@69 1908 #endif /* !Z_SOLO */
jpayne@69 1909
jpayne@69 1910 /* undocumented functions */
jpayne@69 1911 ZEXTERN const char * ZEXPORT zError OF((int));
jpayne@69 1912 ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp));
jpayne@69 1913 ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table OF((void));
jpayne@69 1914 ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int));
jpayne@69 1915 ZEXTERN int ZEXPORT inflateValidate OF((z_streamp, int));
jpayne@69 1916 ZEXTERN unsigned long ZEXPORT inflateCodesUsed OF((z_streamp));
jpayne@69 1917 ZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp));
jpayne@69 1918 ZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp));
jpayne@69 1919 #if defined(_WIN32) && !defined(Z_SOLO)
jpayne@69 1920 ZEXTERN gzFile ZEXPORT gzopen_w OF((const wchar_t *path,
jpayne@69 1921 const char *mode));
jpayne@69 1922 #endif
jpayne@69 1923 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
jpayne@69 1924 # ifndef Z_SOLO
jpayne@69 1925 ZEXTERN int ZEXPORTVA gzvprintf Z_ARG((gzFile file,
jpayne@69 1926 const char *format,
jpayne@69 1927 va_list va));
jpayne@69 1928 # endif
jpayne@69 1929 #endif
jpayne@69 1930
jpayne@69 1931 #ifdef __cplusplus
jpayne@69 1932 }
jpayne@69 1933 #endif
jpayne@69 1934
jpayne@69 1935 #endif /* ZLIB_H */