1 /* 2 * Copyright (c) 2008 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* zlib.h -- interface of the 'zlib' general purpose compression library 29 * version 1.2.3, July 18th, 2005 30 * 31 * Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler 32 * 33 * This software is provided 'as-is', without any express or implied 34 * warranty. In no event will the authors be held liable for any damages 35 * arising from the use of this software. 36 * 37 * Permission is granted to anyone to use this software for any purpose, 38 * including commercial applications, and to alter it and redistribute it 39 * freely, subject to the following restrictions: 40 * 41 * 1. The origin of this software must not be misrepresented; you must not 42 * claim that you wrote the original software. If you use this software 43 * in a product, an acknowledgment in the product documentation would be 44 * appreciated but is not required. 45 * 2. Altered source versions must be plainly marked as such, and must not be 46 * misrepresented as being the original software. 47 * 3. This notice may not be removed or altered from any source distribution. 48 * 49 * Jean-loup Gailly Mark Adler 50 * [email protected] [email protected] 51 * 52 * 53 * The data format used by the zlib library is described by RFCs (Request for 54 * Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt 55 * (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). 56 */ 57 58 #ifndef ZLIB_H 59 #define ZLIB_H 60 61 #ifdef __cplusplus 62 extern "C" { 63 #endif 64 65 #include "zconf.h" 66 67 #define ZLIB_VERSION "1.2.3" 68 #define ZLIB_VERNUM 0x1230 69 70 /* 71 * The 'zlib' compression library provides in-memory compression and 72 * decompression functions, including integrity checks of the uncompressed 73 * data. This version of the library supports only one compression method 74 * (deflation) but other algorithms will be added later and will have the same 75 * stream interface. 76 * 77 * Compression can be done in a single step if the buffers are large 78 * enough (for example if an input file is mmap'ed), or can be done by 79 * repeated calls of the compression function. In the latter case, the 80 * application must provide more input and/or consume the output 81 * (providing more output space) before each call. 82 * 83 * The compressed data format used by default by the in-memory functions is 84 * the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped 85 * around a deflate stream, which is itself documented in RFC 1951. 86 * 87 * The library also supports reading and writing files in gzip (.gz) format 88 * with an interface similar to that of stdio using the functions that start 89 * with "gz". The gzip format is different from the zlib format. gzip is a 90 * gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. 91 * 92 * This library can optionally read and write gzip streams in memory as well. 93 * 94 * The zlib format was designed to be compact and fast for use in memory 95 * and on communications channels. The gzip format was designed for single- 96 * file compression on file systems, has a larger header than zlib to maintain 97 * directory information, and uses a different, slower check method than zlib. 98 * 99 * The library does not install any signal handler. The decoder checks 100 * the consistency of the compressed data, so the library should never 101 * crash even in case of corrupted input. 102 */ 103 104 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); 105 typedef void (*free_func) OF((voidpf opaque, voidpf address)); 106 107 struct internal_state; 108 109 typedef struct z_stream_s { 110 Bytef *next_in;/* next input byte */ 111 uInt avail_in;/* number of bytes available at next_in */ 112 uLong total_in;/* total nb of input bytes read so far */ 113 114 Bytef *next_out;/* next output byte should be put there */ 115 uInt avail_out;/* remaining free space at next_out */ 116 uLong total_out;/* total nb of bytes output so far */ 117 118 char *msg; /* last error message, NULL if no error */ 119 struct internal_state FAR *state; /* not visible by applications */ 120 121 alloc_func zalloc; /* used to allocate the internal state */ 122 free_func zfree;/* used to free the internal state */ 123 voidpf opaque;/* private data object passed to zalloc and zfree */ 124 125 int data_type;/* best guess about the data type: binary or text */ 126 uLong adler; /* adler32 value of the uncompressed data */ 127 uLong reserved;/* reserved for future use */ 128 } z_stream; 129 130 typedef z_stream FAR *z_streamp; 131 132 /* 133 * gzip header information passed to and from zlib routines. See RFC 1952 134 * for more details on the meanings of these fields. 135 */ 136 typedef struct gz_header_s { 137 int text; /* true if compressed data believed to be text */ 138 uLong time; /* modification time */ 139 int xflags; /* extra flags (not used when writing a gzip file) */ 140 int os; /* operating system */ 141 Bytef *extra; /* pointer to extra field or Z_NULL if none */ 142 uInt extra_len;/* extra field length (valid if extra != Z_NULL) */ 143 uInt extra_max;/* space at extra (only when reading header) */ 144 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ 145 uInt name_max;/* space at name (only when reading header) */ 146 Bytef *comment;/* pointer to zero-terminated comment or Z_NULL */ 147 uInt comm_max;/* space at comment (only when reading header) */ 148 int hcrc; /* true if there was or will be a header crc */ 149 int done; /* true when done reading gzip header (not used 150 * when writing a gzip file) */ 151 } gz_header; 152 153 typedef gz_header FAR *gz_headerp; 154 155 /* 156 * The application must update next_in and avail_in when avail_in has 157 * dropped to zero. It must update next_out and avail_out when avail_out 158 * has dropped to zero. The application must initialize zalloc, zfree and 159 * opaque before calling the init function. All other fields are set by the 160 * compression library and must not be updated by the application. 161 * 162 * The opaque value provided by the application will be passed as the first 163 * parameter for calls of zalloc and zfree. This can be useful for custom 164 * memory management. The compression library attaches no meaning to the 165 * opaque value. 166 * 167 * zalloc must return Z_NULL if there is not enough memory for the object. 168 * If zlib is used in a multi-threaded application, zalloc and zfree must be 169 * thread safe. 170 * 171 * On 16-bit systems, the functions zalloc and zfree must be able to allocate 172 * exactly 65536 bytes, but will not be required to allocate more than this 173 * if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, 174 * pointers returned by zalloc for objects of exactly 65536 bytes *must* 175 * have their offset normalized to zero. The default allocation function 176 * provided by this library ensures this (see zutil.c). To reduce memory 177 * requirements and avoid any allocation of 64K objects, at the expense of 178 * compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). 179 * 180 * The fields total_in and total_out can be used for statistics or 181 * progress reports. After compression, total_in holds the total size of 182 * the uncompressed data and may be saved for use in the decompressor 183 * (particularly if the decompressor wants to decompress everything in 184 * a single step). 185 */ 186 187 /* constants */ 188 189 #define Z_NO_FLUSH 0 190 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ 191 /* 2 is a reserved value (in zlib 1.2.3, Z_PACKET_FLUSH was removed) */ 192 #define Z_SYNC_FLUSH 3 193 #define Z_FULL_FLUSH 4 194 #define Z_FINISH 5 195 #define Z_BLOCK 6 196 197 /* Allowed flush values; see deflate() and inflate() below for details */ 198 199 #define Z_OK 0 200 #define Z_STREAM_END 1 201 #define Z_NEED_DICT 2 202 #define Z_ERRNO (-1) 203 #define Z_STREAM_ERROR (-2) 204 #define Z_DATA_ERROR (-3) 205 #define Z_MEM_ERROR (-4) 206 #define Z_BUF_ERROR (-5) 207 #define Z_VERSION_ERROR (-6) 208 /* Return codes for the compression/decompression functions. Negative 209 * values are errors, positive values are used for special but normal events. 210 */ 211 212 #define Z_NO_COMPRESSION 0 213 #define Z_BEST_SPEED 1 214 #define Z_BEST_COMPRESSION 9 215 #define Z_DEFAULT_COMPRESSION (-1) 216 /* compression levels */ 217 218 #define Z_FILTERED 1 219 #define Z_HUFFMAN_ONLY 2 220 #define Z_RLE 3 221 #define Z_FIXED 4 222 #define Z_DEFAULT_STRATEGY 0 223 /* compression strategy; see deflateInit2() below for details */ 224 225 #define Z_BINARY 0 226 #define Z_TEXT 1 227 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ 228 #define Z_UNKNOWN 2 229 /* Possible values of the data_type field (though see inflate()) */ 230 231 #define Z_DEFLATED 8 232 /* The deflate compression method (the only one supported in this version) */ 233 234 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ 235 236 #define zlib_version zlibVersion() 237 /* for compatibility with versions < 1.0.2 */ 238 239 /* basic functions */ 240 241 ZEXTERN const char * ZEXPORT zlibVersion OF((void)); 242 /* The application can compare zlibVersion and ZLIB_VERSION for consistency. 243 * If the first character differs, the library code actually used is 244 * not compatible with the zlib.h header file used by the application. 245 * This check is automatically made by deflateInit and inflateInit. 246 */ 247 248 /* 249 * ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); 250 * 251 * Initializes the internal stream state for compression. The fields 252 * zalloc, zfree and opaque must be initialized before by the caller. 253 * If zalloc and zfree are set to Z_NULL, deflateInit updates them to 254 * use default allocation functions. 255 * 256 * The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: 257 * 1 gives best speed, 9 gives best compression, 0 gives no compression at 258 * all (the input data is simply copied a block at a time). 259 * Z_DEFAULT_COMPRESSION requests a default compromise between speed and 260 * compression (currently equivalent to level 6). 261 * 262 * deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not 263 * enough memory, Z_STREAM_ERROR if level is not a valid compression level, 264 * Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible 265 * with the version assumed by the caller (ZLIB_VERSION). 266 * msg is set to null if there is no error message. deflateInit does not 267 * perform any compression: this will be done by deflate(). 268 */ 269 270 271 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); 272 /* 273 * deflate compresses as much data as possible, and stops when the input 274 * buffer becomes empty or the output buffer becomes full. It may introduce some 275 * output latency (reading input without producing any output) except when 276 * forced to flush. 277 * 278 * The detailed semantics are as follows. deflate performs one or both of the 279 * following actions: 280 * 281 * - Compress more input starting at next_in and update next_in and avail_in 282 * accordingly. If not all input can be processed (because there is not 283 * enough room in the output buffer), next_in and avail_in are updated and 284 * processing will resume at this point for the next call of deflate(). 285 * 286 * - Provide more output starting at next_out and update next_out and avail_out 287 * accordingly. This action is forced if the parameter flush is non zero. 288 * Forcing flush frequently degrades the compression ratio, so this parameter 289 * should be set only when necessary (in interactive applications). 290 * Some output may be provided even if flush is not set. 291 * 292 * Before the call of deflate(), the application should ensure that at least 293 * one of the actions is possible, by providing more input and/or consuming 294 * more output, and updating avail_in or avail_out accordingly; avail_out 295 * should never be zero before the call. The application can consume the 296 * compressed output when it wants, for example when the output buffer is full 297 * (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK 298 * and with zero avail_out, it must be called again after making room in the 299 * output buffer because there might be more output pending. 300 * 301 * Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to 302 * decide how much data to accumualte before producing output, in order to 303 * maximize compression. 304 * 305 * If the parameter flush is set to Z_SYNC_FLUSH, all pending output is 306 * flushed to the output buffer and the output is aligned on a byte boundary, so 307 * that the decompressor can get all input data available so far. (In particular 308 * avail_in is zero after the call if enough output space has been provided 309 * before the call.) Flushing may degrade compression for some compression 310 * algorithms and so it should be used only when necessary. 311 * 312 * If flush is set to Z_FULL_FLUSH, all output is flushed as with 313 * Z_SYNC_FLUSH, and the compression state is reset so that decompression can 314 * restart from this point if previous compressed data has been damaged or if 315 * random access is desired. Using Z_FULL_FLUSH too often can seriously degrade 316 * compression. 317 * 318 * If deflate returns with avail_out == 0, this function must be called again 319 * with the same value of the flush parameter and more output space (updated 320 * avail_out), until the flush is complete (deflate returns with non-zero 321 * avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that 322 * avail_out is greater than six to avoid repeated flush markers due to 323 * avail_out == 0 on return. 324 * 325 * If the parameter flush is set to Z_FINISH, pending input is processed, 326 * pending output is flushed and deflate returns with Z_STREAM_END if there 327 * was enough output space; if deflate returns with Z_OK, this function must be 328 * called again with Z_FINISH and more output space (updated avail_out) but no 329 * more input data, until it returns with Z_STREAM_END or an error. After 330 * deflate has returned Z_STREAM_END, the only possible operations on the 331 * stream are deflateReset or deflateEnd. 332 * 333 * Z_FINISH can be used immediately after deflateInit if all the compression 334 * is to be done in a single step. In this case, avail_out must be at least 335 * the value returned by deflateBound (see below). If deflate does not return 336 * Z_STREAM_END, then it must be called again as described above. 337 * 338 * deflate() sets strm->adler to the adler32 checksum of all input read 339 * so far (that is, total_in bytes). 340 * 341 * deflate() may update strm->data_type if it can make a good guess about 342 * the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered 343 * binary. This field is only for information purposes and does not affect 344 * the compression algorithm in any manner. 345 * 346 * deflate() returns Z_OK if some progress has been made (more input 347 * processed or more output produced), Z_STREAM_END if all input has been 348 * consumed and all output has been produced (only when flush is set to 349 * Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example 350 * if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible 351 * (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not 352 * fatal, and deflate() can be called again with more input and more output 353 * space to continue compressing. 354 */ 355 356 357 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); 358 /* 359 * All dynamically allocated data structures for this stream are freed. 360 * This function discards any unprocessed input and does not flush any 361 * pending output. 362 * 363 * deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the 364 * stream state was inconsistent, Z_DATA_ERROR if the stream was freed 365 * prematurely (some input or output was discarded). In the error case, 366 * msg may be set but then points to a static string (which must not be 367 * deallocated). 368 */ 369 370 371 /* 372 * ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); 373 * 374 * Initializes the internal stream state for decompression. The fields 375 * next_in, avail_in, zalloc, zfree and opaque must be initialized before by 376 * the caller. If next_in is not Z_NULL and avail_in is large enough (the exact 377 * value depends on the compression method), inflateInit determines the 378 * compression method from the zlib header and allocates all data structures 379 * accordingly; otherwise the allocation will be deferred to the first call of 380 * inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to 381 * use default allocation functions. 382 * 383 * inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 384 * memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 385 * version assumed by the caller. msg is set to null if there is no error 386 * message. inflateInit does not perform any decompression apart from reading 387 * the zlib header if present: this will be done by inflate(). (So next_in and 388 * avail_in may be modified, but next_out and avail_out are unchanged.) 389 */ 390 391 392 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); 393 /* 394 * inflate decompresses as much data as possible, and stops when the input 395 * buffer becomes empty or the output buffer becomes full. It may introduce 396 * some output latency (reading input without producing any output) except when 397 * forced to flush. 398 * 399 * The detailed semantics are as follows. inflate performs one or both of the 400 * following actions: 401 * 402 * - Decompress more input starting at next_in and update next_in and avail_in 403 * accordingly. If not all input can be processed (because there is not 404 * enough room in the output buffer), next_in is updated and processing 405 * will resume at this point for the next call of inflate(). 406 * 407 * - Provide more output starting at next_out and update next_out and avail_out 408 * accordingly. inflate() provides as much output as possible, until there 409 * is no more input data or no more space in the output buffer (see below 410 * about the flush parameter). 411 * 412 * Before the call of inflate(), the application should ensure that at least 413 * one of the actions is possible, by providing more input and/or consuming 414 * more output, and updating the next_* and avail_* values accordingly. 415 * The application can consume the uncompressed output when it wants, for 416 * example when the output buffer is full (avail_out == 0), or after each 417 * call of inflate(). If inflate returns Z_OK and with zero avail_out, it 418 * must be called again after making room in the output buffer because there 419 * might be more output pending. 420 * 421 * The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, 422 * Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much 423 * output as possible to the output buffer. Z_BLOCK requests that inflate() stop 424 * if and when it gets to the next deflate block boundary. When decoding the 425 * zlib or gzip format, this will cause inflate() to return immediately after 426 * the header and before the first block. When doing a raw inflate, inflate() 427 * will go ahead and process the first block, and will return when it gets to 428 * the end of that block, or when it runs out of data. 429 * 430 * The Z_BLOCK option assists in appending to or combining deflate streams. 431 * Also to assist in this, on return inflate() will set strm->data_type to the 432 * number of unused bits in the last byte taken from strm->next_in, plus 64 433 * if inflate() is currently decoding the last block in the deflate stream, 434 * plus 128 if inflate() returned immediately after decoding an end-of-block 435 * code or decoding the complete header up to just before the first byte of the 436 * deflate stream. The end-of-block will not be indicated until all of the 437 * uncompressed data from that block has been written to strm->next_out. The 438 * number of unused bits may in general be greater than seven, except when 439 * bit 7 of data_type is set, in which case the number of unused bits will be 440 * less than eight. 441 * 442 * inflate() should normally be called until it returns Z_STREAM_END or an 443 * error. However if all decompression is to be performed in a single step 444 * (a single call of inflate), the parameter flush should be set to 445 * Z_FINISH. In this case all pending input is processed and all pending 446 * output is flushed; avail_out must be large enough to hold all the 447 * uncompressed data. (The size of the uncompressed data may have been saved 448 * by the compressor for this purpose.) The next operation on this stream must 449 * be inflateEnd to deallocate the decompression state. The use of Z_FINISH 450 * is never required, but can be used to inform inflate that a faster approach 451 * may be used for the single inflate() call. 452 * 453 * In this implementation, inflate() always flushes as much output as 454 * possible to the output buffer, and always uses the faster approach on the 455 * first call. So the only effect of the flush parameter in this implementation 456 * is on the return value of inflate(), as noted below, or when it returns early 457 * because Z_BLOCK is used. 458 * 459 * If a preset dictionary is needed after this call (see inflateSetDictionary 460 * below), inflate sets strm->adler to the adler32 checksum of the dictionary 461 * chosen by the compressor and returns Z_NEED_DICT; otherwise it sets 462 * strm->adler to the adler32 checksum of all output produced so far (that is, 463 * total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described 464 * below. At the end of the stream, inflate() checks that its computed adler32 465 * checksum is equal to that saved by the compressor and returns Z_STREAM_END 466 * only if the checksum is correct. 467 * 468 * inflate() will decompress and check either zlib-wrapped or gzip-wrapped 469 * deflate data. The header type is detected automatically. Any information 470 * contained in the gzip header is not retained, so applications that need that 471 * information should instead use raw inflate, see inflateInit2() below, or 472 * inflateBack() and perform their own processing of the gzip header and 473 * trailer. 474 * 475 * inflate() returns Z_OK if some progress has been made (more input processed 476 * or more output produced), Z_STREAM_END if the end of the compressed data has 477 * been reached and all uncompressed output has been produced, Z_NEED_DICT if a 478 * preset dictionary is needed at this point, Z_DATA_ERROR if the input data was 479 * corrupted (input stream not conforming to the zlib format or incorrect check 480 * value), Z_STREAM_ERROR if the stream structure was inconsistent (for example 481 * if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, 482 * Z_BUF_ERROR if no progress is possible or if there was not enough room in the 483 * output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and 484 * inflate() can be called again with more input and more output space to 485 * continue decompressing. If Z_DATA_ERROR is returned, the application may then 486 * call inflateSync() to look for a good compression block if a partial recovery 487 * of the data is desired. 488 */ 489 490 491 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); 492 /* 493 * All dynamically allocated data structures for this stream are freed. 494 * This function discards any unprocessed input and does not flush any 495 * pending output. 496 * 497 * inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state 498 * was inconsistent. In the error case, msg may be set but then points to a 499 * static string (which must not be deallocated). 500 */ 501 502 /* Advanced functions */ 503 504 /* 505 * The following functions are needed only in some special applications. 506 */ 507 508 /* 509 * ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, 510 * int level, 511 * int method, 512 * int windowBits, 513 * int memLevel, 514 * int strategy)); 515 * 516 * This is another version of deflateInit with more compression options. The 517 * fields next_in, zalloc, zfree and opaque must be initialized before by 518 * the caller. 519 * 520 * The method parameter is the compression method. It must be Z_DEFLATED in 521 * this version of the library. 522 * 523 * The windowBits parameter is the base two logarithm of the window size 524 * (the size of the history buffer). It should be in the range 8..15 for this 525 * version of the library. Larger values of this parameter result in better 526 * compression at the expense of memory usage. The default value is 15 if 527 * deflateInit is used instead. 528 * 529 * windowBits can also be -8..-15 for raw deflate. In this case, -windowBits 530 * determines the window size. deflate() will then generate raw deflate data 531 * with no zlib header or trailer, and will not compute an adler32 check value. 532 * 533 * windowBits can also be greater than 15 for optional gzip encoding. Add 534 * 16 to windowBits to write a simple gzip header and trailer around the 535 * compressed data instead of a zlib wrapper. The gzip header will have no 536 * file name, no extra data, no comment, no modification time (set to zero), 537 * no header crc, and the operating system will be set to 255 (unknown). If a 538 * gzip stream is being written, strm->adler is a crc32 instead of an adler32. 539 * 540 * The memLevel parameter specifies how much memory should be allocated 541 * for the internal compression state. memLevel=1 uses minimum memory but 542 * is slow and reduces compression ratio; memLevel=9 uses maximum memory 543 * for optimal speed. The default value is 8. See zconf.h for total memory 544 * usage as a function of windowBits and memLevel. 545 * 546 * The strategy parameter is used to tune the compression algorithm. Use the 547 * value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a 548 * filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no 549 * string match), or Z_RLE to limit match distances to one (run-length 550 * encoding). Filtered data consists mostly of small values with a somewhat 551 * random distribution. In this case, the compression algorithm is tuned to 552 * compress them better. The effect of Z_FILTERED is to force more Huffman 553 * coding and less string matching; it is somewhat intermediate between 554 * Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as 555 * Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy 556 * parameter only affects the compression ratio but not the correctness of the 557 * compressed output even if it is not set appropriately. Z_FIXED prevents the 558 * use of dynamic Huffman codes, allowing for a simpler decoder for special 559 * applications. 560 * 561 * deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 562 * memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid 563 * method). msg is set to null if there is no error message. deflateInit2 does 564 * not perform any compression: this will be done by deflate(). 565 */ 566 567 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, 568 const Bytef *dictionary, 569 uInt dictLength)); 570 /* 571 * Initializes the compression dictionary from the given byte sequence 572 * without producing any compressed output. This function must be called 573 * immediately after deflateInit, deflateInit2 or deflateReset, before any 574 * call of deflate. The compressor and decompressor must use exactly the same 575 * dictionary (see inflateSetDictionary). 576 * 577 * The dictionary should consist of strings (byte sequences) that are likely 578 * to be encountered later in the data to be compressed, with the most commonly 579 * used strings preferably put towards the end of the dictionary. Using a 580 * dictionary is most useful when the data to be compressed is short and can be 581 * predicted with good accuracy; the data can then be compressed better than 582 * with the default empty dictionary. 583 * 584 * Depending on the size of the compression data structures selected by 585 * deflateInit or deflateInit2, a part of the dictionary may in effect be 586 * discarded, for example if the dictionary is larger than the window size in 587 * deflate or deflate2. Thus the strings most likely to be useful should be 588 * put at the end of the dictionary, not at the front. In addition, the 589 * current implementation of deflate will use at most the window size minus 590 * 262 bytes of the provided dictionary. 591 * 592 * Upon return of this function, strm->adler is set to the adler32 value 593 * of the dictionary; the decompressor may later use this value to determine 594 * which dictionary has been used by the compressor. (The adler32 value 595 * applies to the whole dictionary even if only a subset of the dictionary is 596 * actually used by the compressor.) If a raw deflate was requested, then the 597 * adler32 value is not computed and strm->adler is not set. 598 * 599 * deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a 600 * parameter is invalid (such as NULL dictionary) or the stream state is 601 * inconsistent (for example if deflate has already been called for this stream 602 * or if the compression method is bsort). deflateSetDictionary does not 603 * perform any compression: this will be done by deflate(). 604 */ 605 606 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, 607 z_streamp source)); 608 /* 609 * Sets the destination stream as a complete copy of the source stream. 610 * 611 * This function can be useful when several compression strategies will be 612 * tried, for example when there are several ways of pre-processing the input 613 * data with a filter. The streams that will be discarded should then be freed 614 * by calling deflateEnd. Note that deflateCopy duplicates the internal 615 * compression state which can be quite large, so this strategy is slow and 616 * can consume lots of memory. 617 * 618 * deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 619 * enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 620 * (such as zalloc being NULL). msg is left unchanged in both source and 621 * destination. 622 */ 623 624 #if XNU_KERNEL_PRIVATE 625 626 typedef int (*z_input_func) (z_streamp strm, Bytef *buf, unsigned size); 627 typedef int (*z_output_func)(z_streamp strm, Bytef *buf, unsigned size); 628 629 ZEXTERN int ZEXPORT deflateResetWithIO(z_streamp strm, z_input_func zinput, z_output_func zoutput); 630 631 #endif /* XNU_KERNEL_PRIVATE */ 632 633 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); 634 /* 635 * This function is equivalent to deflateEnd followed by deflateInit, 636 * but does not free and reallocate all the internal compression state. 637 * The stream will keep the same compression level and any other attributes 638 * that may have been set by deflateInit2. 639 * 640 * deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 641 * stream state was inconsistent (such as zalloc or state being NULL). 642 */ 643 644 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, 645 int level, 646 int strategy)); 647 /* 648 * Dynamically update the compression level and compression strategy. The 649 * interpretation of level and strategy is as in deflateInit2. This can be 650 * used to switch between compression and straight copy of the input data, or 651 * to switch to a different kind of input data requiring a different 652 * strategy. If the compression level is changed, the input available so far 653 * is compressed with the old level (and may be flushed); the new level will 654 * take effect only at the next call of deflate(). 655 * 656 * Before the call of deflateParams, the stream state must be set as for 657 * a call of deflate(), since the currently available input may have to 658 * be compressed and flushed. In particular, strm->avail_out must be non-zero. 659 * 660 * deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source 661 * stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR 662 * if strm->avail_out was zero. 663 */ 664 665 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, 666 int good_length, 667 int max_lazy, 668 int nice_length, 669 int max_chain)); 670 /* 671 * Fine tune deflate's internal compression parameters. This should only be 672 * used by someone who understands the algorithm used by zlib's deflate for 673 * searching for the best matching string, and even then only by the most 674 * fanatic optimizer trying to squeeze out the last compressed bit for their 675 * specific input data. Read the deflate.c source code for the meaning of the 676 * max_lazy, good_length, nice_length, and max_chain parameters. 677 * 678 * deflateTune() can be called after deflateInit() or deflateInit2(), and 679 * returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. 680 */ 681 682 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, 683 uLong sourceLen)); 684 /* 685 * deflateBound() returns an upper bound on the compressed size after 686 * deflation of sourceLen bytes. It must be called after deflateInit() 687 * or deflateInit2(). This would be used to allocate an output buffer 688 * for deflation in a single pass, and so would be called before deflate(). 689 */ 690 691 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, 692 int bits, 693 int value)); 694 /* 695 * deflatePrime() inserts bits in the deflate output stream. The intent 696 * is that this function is used to start off the deflate output with the 697 * bits leftover from a previous deflate stream when appending to it. As such, 698 * this function can only be used for raw deflate, and must be used before the 699 * first deflate() call after a deflateInit2() or deflateReset(). bits must be 700 * less than or equal to 16, and that many of the least significant bits of 701 * value will be inserted in the output. 702 * 703 * deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source 704 * stream state was inconsistent. 705 */ 706 707 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, 708 gz_headerp head)); 709 /* 710 * deflateSetHeader() provides gzip header information for when a gzip 711 * stream is requested by deflateInit2(). deflateSetHeader() may be called 712 * after deflateInit2() or deflateReset() and before the first call of 713 * deflate(). The text, time, os, extra field, name, and comment information 714 * in the provided gz_header structure are written to the gzip header (xflag is 715 * ignored -- the extra flags are set according to the compression level). The 716 * caller must assure that, if not Z_NULL, name and comment are terminated with 717 * a zero byte, and that if extra is not Z_NULL, that extra_len bytes are 718 * available there. If hcrc is true, a gzip header crc is included. Note that 719 * the current versions of the command-line version of gzip (up through version 720 * 1.3.x) do not support header crc's, and will report that it is a "multi-part 721 * gzip file" and give up. 722 * 723 * If deflateSetHeader is not used, the default gzip header has text false, 724 * the time set to zero, and os set to 255, with no extra, name, or comment 725 * fields. The gzip header is returned to the default state by deflateReset(). 726 * 727 * deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 728 * stream state was inconsistent. 729 */ 730 731 /* 732 * ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, 733 * int windowBits)); 734 * 735 * This is another version of inflateInit with an extra parameter. The 736 * fields next_in, avail_in, zalloc, zfree and opaque must be initialized 737 * before by the caller. 738 * 739 * The windowBits parameter is the base two logarithm of the maximum window 740 * size (the size of the history buffer). It should be in the range 8..15 for 741 * this version of the library. The default value is 15 if inflateInit is used 742 * instead. windowBits must be greater than or equal to the windowBits value 743 * provided to deflateInit2() while compressing, or it must be equal to 15 if 744 * deflateInit2() was not used. If a compressed stream with a larger window 745 * size is given as input, inflate() will return with the error code 746 * Z_DATA_ERROR instead of trying to allocate a larger window. 747 * 748 * windowBits can also be -8..-15 for raw inflate. In this case, -windowBits 749 * determines the window size. inflate() will then process raw deflate data, 750 * not looking for a zlib or gzip header, not generating a check value, and not 751 * looking for any check values for comparison at the end of the stream. This 752 * is for use with other formats that use the deflate compressed data format 753 * such as zip. Those formats provide their own check values. If a custom 754 * format is developed using the raw deflate format for compressed data, it is 755 * recommended that a check value such as an adler32 or a crc32 be applied to 756 * the uncompressed data as is done in the zlib, gzip, and zip formats. For 757 * most applications, the zlib format should be used as is. Note that comments 758 * above on the use in deflateInit2() applies to the magnitude of windowBits. 759 * 760 * windowBits can also be greater than 15 for optional gzip decoding. Add 761 * 32 to windowBits to enable zlib and gzip decoding with automatic header 762 * detection, or add 16 to decode only the gzip format (the zlib format will 763 * return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is 764 * a crc32 instead of an adler32. 765 * 766 * inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 767 * memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg 768 * is set to null if there is no error message. inflateInit2 does not perform 769 * any decompression apart from reading the zlib header if present: this will 770 * be done by inflate(). (So next_in and avail_in may be modified, but next_out 771 * and avail_out are unchanged.) 772 */ 773 774 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, 775 const Bytef *dictionary, 776 uInt dictLength)); 777 /* 778 * Initializes the decompression dictionary from the given uncompressed byte 779 * sequence. This function must be called immediately after a call of inflate, 780 * if that call returned Z_NEED_DICT. The dictionary chosen by the compressor 781 * can be determined from the adler32 value returned by that call of inflate. 782 * The compressor and decompressor must use exactly the same dictionary (see 783 * deflateSetDictionary). For raw inflate, this function can be called 784 * immediately after inflateInit2() or inflateReset() and before any call of 785 * inflate() to set the dictionary. The application must insure that the 786 * dictionary that was used for compression is provided. 787 * 788 * inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a 789 * parameter is invalid (such as NULL dictionary) or the stream state is 790 * inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the 791 * expected one (incorrect adler32 value). inflateSetDictionary does not 792 * perform any decompression: this will be done by subsequent calls of 793 * inflate(). 794 */ 795 796 ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); 797 /* 798 * Skips invalid compressed data until a full flush point (see above the 799 * description of deflate with Z_FULL_FLUSH) can be found, or until all 800 * available input is skipped. No output is provided. 801 * 802 * inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR 803 * if no more input was provided, Z_DATA_ERROR if no flush point has been found, 804 * or Z_STREAM_ERROR if the stream structure was inconsistent. In the success 805 * case, the application may save the current current value of total_in which 806 * indicates where valid compressed data was found. In the error case, the 807 * application may repeatedly call inflateSync, providing more input each time, 808 * until success or end of the input data. 809 */ 810 811 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, 812 z_streamp source)); 813 /* 814 * Sets the destination stream as a complete copy of the source stream. 815 * 816 * This function can be useful when randomly accessing a large stream. The 817 * first pass through the stream can periodically record the inflate state, 818 * allowing restarting inflate at those points when randomly accessing the 819 * stream. 820 * 821 * inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 822 * enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 823 * (such as zalloc being NULL). msg is left unchanged in both source and 824 * destination. 825 */ 826 827 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); 828 /* 829 * This function is equivalent to inflateEnd followed by inflateInit, 830 * but does not free and reallocate all the internal decompression state. 831 * The stream will keep attributes that may have been set by inflateInit2. 832 * 833 * inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 834 * stream state was inconsistent (such as zalloc or state being NULL). 835 */ 836 837 ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, 838 int bits, 839 int value)); 840 /* 841 * This function inserts bits in the inflate input stream. The intent is 842 * that this function is used to start inflating at a bit position in the 843 * middle of a byte. The provided bits will be used before any bytes are used 844 * from next_in. This function should only be used with raw inflate, and 845 * should be used before the first inflate() call after inflateInit2() or 846 * inflateReset(). bits must be less than or equal to 16, and that many of the 847 * least significant bits of value will be inserted in the input. 848 * 849 * inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source 850 * stream state was inconsistent. 851 */ 852 853 ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, 854 gz_headerp head)); 855 /* 856 * inflateGetHeader() requests that gzip header information be stored in the 857 * provided gz_header structure. inflateGetHeader() may be called after 858 * inflateInit2() or inflateReset(), and before the first call of inflate(). 859 * As inflate() processes the gzip stream, head->done is zero until the header 860 * is completed, at which time head->done is set to one. If a zlib stream is 861 * being decoded, then head->done is set to -1 to indicate that there will be 862 * no gzip header information forthcoming. Note that Z_BLOCK can be used to 863 * force inflate() to return immediately after header processing is complete 864 * and before any actual data is decompressed. 865 * 866 * The text, time, xflags, and os fields are filled in with the gzip header 867 * contents. hcrc is set to true if there is a header CRC. (The header CRC 868 * was valid if done is set to one.) If extra is not Z_NULL, then extra_max 869 * contains the maximum number of bytes to write to extra. Once done is true, 870 * extra_len contains the actual extra field length, and extra contains the 871 * extra field, or that field truncated if extra_max is less than extra_len. 872 * If name is not Z_NULL, then up to name_max characters are written there, 873 * terminated with a zero unless the length is greater than name_max. If 874 * comment is not Z_NULL, then up to comm_max characters are written there, 875 * terminated with a zero unless the length is greater than comm_max. When 876 * any of extra, name, or comment are not Z_NULL and the respective field is 877 * not present in the header, then that field is set to Z_NULL to signal its 878 * absence. This allows the use of deflateSetHeader() with the returned 879 * structure to duplicate the header. However if those fields are set to 880 * allocated memory, then the application will need to save those pointers 881 * elsewhere so that they can be eventually freed. 882 * 883 * If inflateGetHeader is not used, then the header information is simply 884 * discarded. The header is always checked for validity, including the header 885 * CRC if present. inflateReset() will reset the process to discard the header 886 * information. The application would need to call inflateGetHeader() again to 887 * retrieve the header from the next gzip stream. 888 * 889 * inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source 890 * stream state was inconsistent. 891 */ 892 893 /* 894 * ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, 895 * unsigned char FAR *window)); 896 * 897 * Initialize the internal stream state for decompression using inflateBack() 898 * calls. The fields zalloc, zfree and opaque in strm must be initialized 899 * before the call. If zalloc and zfree are Z_NULL, then the default library- 900 * derived memory allocation routines are used. windowBits is the base two 901 * logarithm of the window size, in the range 8..15. window is a caller 902 * supplied buffer of that size. Except for special applications where it is 903 * assured that deflate was used with small window sizes, windowBits must be 15 904 * and a 32K byte window must be supplied to be able to decompress general 905 * deflate streams. 906 * 907 * See inflateBack() for the usage of these routines. 908 * 909 * inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of 910 * the paramaters are invalid, Z_MEM_ERROR if the internal state could not 911 * be allocated, or Z_VERSION_ERROR if the version of the library does not 912 * match the version of the header file. 913 */ 914 915 typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); 916 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); 917 918 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, 919 in_func in, void FAR *in_desc, 920 out_func out, void FAR *out_desc)); 921 /* 922 * inflateBack() does a raw inflate with a single call using a call-back 923 * interface for input and output. This is more efficient than inflate() for 924 * file i/o applications in that it avoids copying between the output and the 925 * sliding window by simply making the window itself the output buffer. This 926 * function trusts the application to not change the output buffer passed by 927 * the output function, at least until inflateBack() returns. 928 * 929 * inflateBackInit() must be called first to allocate the internal state 930 * and to initialize the state with the user-provided window buffer. 931 * inflateBack() may then be used multiple times to inflate a complete, raw 932 * deflate stream with each call. inflateBackEnd() is then called to free 933 * the allocated state. 934 * 935 * A raw deflate stream is one with no zlib or gzip header or trailer. 936 * This routine would normally be used in a utility that reads zip or gzip 937 * files and writes out uncompressed files. The utility would decode the 938 * header and process the trailer on its own, hence this routine expects 939 * only the raw deflate stream to decompress. This is different from the 940 * normal behavior of inflate(), which expects either a zlib or gzip header and 941 * trailer around the deflate stream. 942 * 943 * inflateBack() uses two subroutines supplied by the caller that are then 944 * called by inflateBack() for input and output. inflateBack() calls those 945 * routines until it reads a complete deflate stream and writes out all of the 946 * uncompressed data, or until it encounters an error. The function's 947 * parameters and return types are defined above in the in_func and out_func 948 * typedefs. inflateBack() will call in(in_desc, &buf) which should return the 949 * number of bytes of provided input, and a pointer to that input in buf. If 950 * there is no input available, in() must return zero--buf is ignored in that 951 * case--and inflateBack() will return a buffer error. inflateBack() will call 952 * out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() 953 * should return zero on success, or non-zero on failure. If out() returns 954 * non-zero, inflateBack() will return with an error. Neither in() nor out() 955 * are permitted to change the contents of the window provided to 956 * inflateBackInit(), which is also the buffer that out() uses to write from. 957 * The length written by out() will be at most the window size. Any non-zero 958 * amount of input may be provided by in(). 959 * 960 * For convenience, inflateBack() can be provided input on the first call by 961 * setting strm->next_in and strm->avail_in. If that input is exhausted, then 962 * in() will be called. Therefore strm->next_in must be initialized before 963 * calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called 964 * immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in 965 * must also be initialized, and then if strm->avail_in is not zero, input will 966 * initially be taken from strm->next_in[0 .. strm->avail_in - 1]. 967 * 968 * The in_desc and out_desc parameters of inflateBack() is passed as the 969 * first parameter of in() and out() respectively when they are called. These 970 * descriptors can be optionally used to pass any information that the caller- 971 * supplied in() and out() functions need to do their job. 972 * 973 * On return, inflateBack() will set strm->next_in and strm->avail_in to 974 * pass back any unused input that was provided by the last in() call. The 975 * return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR 976 * if in() or out() returned an error, Z_DATA_ERROR if there was a format 977 * error in the deflate stream (in which case strm->msg is set to indicate the 978 * nature of the error), or Z_STREAM_ERROR if the stream was not properly 979 * initialized. In the case of Z_BUF_ERROR, an input or output error can be 980 * distinguished using strm->next_in which will be Z_NULL only if in() returned 981 * an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to 982 * out() returning non-zero. (in() will always be called before out(), so 983 * strm->next_in is assured to be defined if out() returns non-zero.) Note 984 * that inflateBack() cannot return Z_OK. 985 */ 986 987 ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); 988 /* 989 * All memory allocated by inflateBackInit() is freed. 990 * 991 * inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream 992 * state was inconsistent. 993 */ 994 995 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); 996 /* Return flags indicating compile-time options. 997 * 998 * Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: 999 * 1.0: size of uInt 1000 * 3.2: size of uLong 1001 * 5.4: size of voidpf (pointer) 1002 * 7.6: size of z_off_t 1003 * 1004 * Compiler, assembler, and debug options: 1005 * 8: DEBUG 1006 * 9: ASMV or ASMINF -- use ASM code 1007 * 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention 1008 * 11: 0 (reserved) 1009 * 1010 * One-time table building (smaller code, but not thread-safe if true): 1011 * 12: BUILDFIXED -- build static block decoding tables when needed 1012 * 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed 1013 * 14,15: 0 (reserved) 1014 * 1015 * Library content (indicates missing functionality): 1016 * 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking 1017 * deflate code when not needed) 1018 * 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect 1019 * and decode gzip streams (to avoid linking crc code) 1020 * 18-19: 0 (reserved) 1021 * 1022 * Operation variations (changes in library functionality): 1023 * 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate 1024 * 21: FASTEST -- deflate algorithm with only one, lowest compression level 1025 * 22,23: 0 (reserved) 1026 * 1027 * The sprintf variant used by gzprintf (zero is best): 1028 * 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format 1029 * 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! 1030 * 26: 0 = returns value, 1 = void -- 1 means inferred string length returned 1031 * 1032 * Remainder: 1033 * 27-31: 0 (reserved) 1034 */ 1035 1036 1037 /* utility functions */ 1038 1039 /* 1040 * The following utility functions are implemented on top of the 1041 * basic stream-oriented functions. To simplify the interface, some 1042 * default options are assumed (compression level and memory usage, 1043 * standard memory allocation functions). The source code of these 1044 * utility functions can easily be modified if you need special options. 1045 */ 1046 1047 ZEXTERN int ZEXPORT compress OF((Bytef * dest, uLongf *destLen, 1048 const Bytef *source, uLong sourceLen)); 1049 /* 1050 * Compresses the source buffer into the destination buffer. sourceLen is 1051 * the byte length of the source buffer. Upon entry, destLen is the total 1052 * size of the destination buffer, which must be at least the value returned 1053 * by compressBound(sourceLen). Upon exit, destLen is the actual size of the 1054 * compressed buffer. 1055 * This function can be used to compress a whole file at once if the 1056 * input file is mmap'ed. 1057 * compress returns Z_OK if success, Z_MEM_ERROR if there was not 1058 * enough memory, Z_BUF_ERROR if there was not enough room in the output 1059 * buffer. 1060 */ 1061 1062 ZEXTERN int ZEXPORT compress2 OF((Bytef * dest, uLongf *destLen, 1063 const Bytef *source, uLong sourceLen, 1064 int level)); 1065 /* 1066 * Compresses the source buffer into the destination buffer. The level 1067 * parameter has the same meaning as in deflateInit. sourceLen is the byte 1068 * length of the source buffer. Upon entry, destLen is the total size of the 1069 * destination buffer, which must be at least the value returned by 1070 * compressBound(sourceLen). Upon exit, destLen is the actual size of the 1071 * compressed buffer. 1072 * 1073 * compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 1074 * memory, Z_BUF_ERROR if there was not enough room in the output buffer, 1075 * Z_STREAM_ERROR if the level parameter is invalid. 1076 */ 1077 1078 ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); 1079 /* 1080 * compressBound() returns an upper bound on the compressed size after 1081 * compress() or compress2() on sourceLen bytes. It would be used before 1082 * a compress() or compress2() call to allocate the destination buffer. 1083 */ 1084 1085 ZEXTERN int ZEXPORT uncompress OF((Bytef * dest, uLongf *destLen, 1086 const Bytef *source, uLong sourceLen)); 1087 /* 1088 * Decompresses the source buffer into the destination buffer. sourceLen is 1089 * the byte length of the source buffer. Upon entry, destLen is the total 1090 * size of the destination buffer, which must be large enough to hold the 1091 * entire uncompressed data. (The size of the uncompressed data must have 1092 * been saved previously by the compressor and transmitted to the decompressor 1093 * by some mechanism outside the scope of this compression library.) 1094 * Upon exit, destLen is the actual size of the compressed buffer. 1095 * This function can be used to decompress a whole file at once if the 1096 * input file is mmap'ed. 1097 * 1098 * uncompress returns Z_OK if success, Z_MEM_ERROR if there was not 1099 * enough memory, Z_BUF_ERROR if there was not enough room in the output 1100 * buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. 1101 */ 1102 1103 #if XNU_KERNEL_PRIVATE 1104 1105 ZEXTERN uLong zlib_deflate_memory_size(int wbits, int memlevel); 1106 1107 #endif /* XNU_KERNEL_PRIVATE */ 1108 1109 #if !KERNEL 1110 1111 typedef voidp gzFile; 1112 1113 ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); 1114 /* 1115 * Opens a gzip (.gz) file for reading or writing. The mode parameter 1116 * is as in fopen ("rb" or "wb") but can also include a compression level 1117 * ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for 1118 * Huffman only compression as in "wb1h", or 'R' for run-length encoding 1119 * as in "wb1R". (See the description of deflateInit2 for more information 1120 * about the strategy parameter.) 1121 * 1122 * gzopen can be used to read a file which is not in gzip format; in this 1123 * case gzread will directly read from the file without decompression. 1124 * 1125 * gzopen returns NULL if the file could not be opened or if there was 1126 * insufficient memory to allocate the (de)compression state; errno 1127 * can be checked to distinguish the two cases (if errno is zero, the 1128 * zlib error is Z_MEM_ERROR). */ 1129 1130 ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); 1131 /* 1132 * gzdopen() associates a gzFile with the file descriptor fd. File 1133 * descriptors are obtained from calls like open, dup, creat, pipe or 1134 * fileno (in the file has been previously opened with fopen). 1135 * The mode parameter is as in gzopen. 1136 * The next call of gzclose on the returned gzFile will also close the 1137 * file descriptor fd, just like fclose(fdopen(fd), mode) closes the file 1138 * descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). 1139 * gzdopen returns NULL if there was insufficient memory to allocate 1140 * the (de)compression state. 1141 */ 1142 1143 ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); 1144 /* 1145 * Dynamically update the compression level or strategy. See the description 1146 * of deflateInit2 for the meaning of these parameters. 1147 * gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not 1148 * opened for writing. 1149 */ 1150 1151 ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); 1152 /* 1153 * Reads the given number of uncompressed bytes from the compressed file. 1154 * If the input file was not in gzip format, gzread copies the given number 1155 * of bytes into the buffer. 1156 * gzread returns the number of uncompressed bytes actually read (0 for 1157 * end of file, -1 for error). */ 1158 1159 ZEXTERN int ZEXPORT gzwrite OF((gzFile file, 1160 voidpc buf, unsigned len)); 1161 /* 1162 * Writes the given number of uncompressed bytes into the compressed file. 1163 * gzwrite returns the number of uncompressed bytes actually written 1164 * (0 in case of error). 1165 */ 1166 1167 ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); 1168 /* 1169 * Converts, formats, and writes the args to the compressed file under 1170 * control of the format string, as in fprintf. gzprintf returns the number of 1171 * uncompressed bytes actually written (0 in case of error). The number of 1172 * uncompressed bytes written is limited to 4095. The caller should assure that 1173 * this limit is not exceeded. If it is exceeded, then gzprintf() will return 1174 * return an error (0) with nothing written. In this case, there may also be a 1175 * buffer overflow with unpredictable consequences, which is possible only if 1176 * zlib was compiled with the insecure functions sprintf() or vsprintf() 1177 * because the secure snprintf() or vsnprintf() functions were not available. 1178 */ 1179 1180 ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); 1181 /* 1182 * Writes the given null-terminated string to the compressed file, excluding 1183 * the terminating null character. 1184 * gzputs returns the number of characters written, or -1 in case of error. 1185 */ 1186 1187 ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); 1188 /* 1189 * Reads bytes from the compressed file until len-1 characters are read, or 1190 * a newline character is read and transferred to buf, or an end-of-file 1191 * condition is encountered. The string is then terminated with a null 1192 * character. 1193 * gzgets returns buf, or Z_NULL in case of error. 1194 */ 1195 1196 ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); 1197 /* 1198 * Writes c, converted to an unsigned char, into the compressed file. 1199 * gzputc returns the value that was written, or -1 in case of error. 1200 */ 1201 1202 ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); 1203 /* 1204 * Reads one byte from the compressed file. gzgetc returns this byte 1205 * or -1 in case of end of file or error. 1206 */ 1207 1208 ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); 1209 /* 1210 * Push one character back onto the stream to be read again later. 1211 * Only one character of push-back is allowed. gzungetc() returns the 1212 * character pushed, or -1 on failure. gzungetc() will fail if a 1213 * character has been pushed but not read yet, or if c is -1. The pushed 1214 * character will be discarded if the stream is repositioned with gzseek() 1215 * or gzrewind(). 1216 */ 1217 1218 ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); 1219 /* 1220 * Flushes all pending output into the compressed file. The parameter 1221 * flush is as in the deflate() function. The return value is the zlib 1222 * error number (see function gzerror below). gzflush returns Z_OK if 1223 * the flush parameter is Z_FINISH and all output could be flushed. 1224 * gzflush should be called only when strictly necessary because it can 1225 * degrade compression. 1226 */ 1227 1228 ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, 1229 z_off_t offset, int whence)); 1230 /* 1231 * Sets the starting position for the next gzread or gzwrite on the 1232 * given compressed file. The offset represents a number of bytes in the 1233 * uncompressed data stream. The whence parameter is defined as in lseek(2); 1234 * the value SEEK_END is not supported. 1235 * If the file is opened for reading, this function is emulated but can be 1236 * extremely slow. If the file is opened for writing, only forward seeks are 1237 * supported; gzseek then compresses a sequence of zeroes up to the new 1238 * starting position. 1239 * 1240 * gzseek returns the resulting offset location as measured in bytes from 1241 * the beginning of the uncompressed stream, or -1 in case of error, in 1242 * particular if the file is opened for writing and the new starting position 1243 * would be before the current position. 1244 */ 1245 1246 ZEXTERN int ZEXPORT gzrewind OF((gzFile file)); 1247 /* 1248 * Rewinds the given file. This function is supported only for reading. 1249 * 1250 * gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) 1251 */ 1252 1253 ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); 1254 /* 1255 * Returns the starting position for the next gzread or gzwrite on the 1256 * given compressed file. This position represents a number of bytes in the 1257 * uncompressed data stream. 1258 * 1259 * gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) 1260 */ 1261 1262 ZEXTERN int ZEXPORT gzeof OF((gzFile file)); 1263 /* 1264 * Returns 1 when EOF has previously been detected reading the given 1265 * input stream, otherwise zero. 1266 */ 1267 1268 ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); 1269 /* 1270 * Returns 1 if file is being read directly without decompression, otherwise 1271 * zero. 1272 */ 1273 1274 ZEXTERN int ZEXPORT gzclose OF((gzFile file)); 1275 /* 1276 * Flushes all pending output if necessary, closes the compressed file 1277 * and deallocates all the (de)compression state. The return value is the zlib 1278 * error number (see function gzerror below). 1279 */ 1280 1281 ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); 1282 /* 1283 * Returns the error message for the last error which occurred on the 1284 * given compressed file. errnum is set to zlib error number. If an 1285 * error occurred in the file system and not in the compression library, 1286 * errnum is set to Z_ERRNO and the application may consult errno 1287 * to get the exact error code. 1288 */ 1289 1290 ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); 1291 /* 1292 * Clears the error and end-of-file flags for file. This is analogous to the 1293 * clearerr() function in stdio. This is useful for continuing to read a gzip 1294 * file that is being written concurrently. 1295 */ 1296 1297 #endif /* KERNEL */ 1298 1299 /* checksum functions */ 1300 1301 /* 1302 * These functions are not related to compression but are exported 1303 * anyway because they might be useful in applications using the 1304 * compression library. 1305 */ 1306 1307 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); 1308 /* 1309 * Update a running Adler-32 checksum with the bytes buf[0..len-1] and 1310 * return the updated checksum. If buf is NULL, this function returns 1311 * the required initial value for the checksum. 1312 * An Adler-32 checksum is almost as reliable as a CRC32 but can be computed 1313 * much faster. Usage example: 1314 * 1315 * uLong adler = adler32(0L, Z_NULL, 0); 1316 * 1317 * while (read_buffer(buffer, length) != EOF) { 1318 * adler = adler32(adler, buffer, length); 1319 * } 1320 * if (adler != original_adler) error(); 1321 */ 1322 1323 ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, 1324 z_off_t len2)); 1325 /* 1326 * Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 1327 * and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for 1328 * each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of 1329 * seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. 1330 */ 1331 1332 ZEXTERN uLong ZEXPORT z_crc32 OF((uLong crc, const Bytef *buf, uInt len)); 1333 /* 1334 * Update a running CRC-32 with the bytes buf[0..len-1] and return the 1335 * updated CRC-32. If buf is NULL, this function returns the required initial 1336 * value for the for the crc. Pre- and post-conditioning (one's complement) is 1337 * performed within this function so it shouldn't be done by the application. 1338 * Usage example: 1339 * 1340 * uLong crc = crc32(0L, Z_NULL, 0); 1341 * 1342 * while (read_buffer(buffer, length) != EOF) { 1343 * crc = crc32(crc, buffer, length); 1344 * } 1345 * if (crc != original_crc) error(); 1346 */ 1347 1348 ZEXTERN uLong ZEXPORT z_crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); 1349 1350 /* 1351 * Combine two CRC-32 check values into one. For two sequences of bytes, 1352 * seq1 and seq2 with lengths len1 and len2, CRC-32 check values were 1353 * calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 1354 * check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and 1355 * len2. 1356 */ 1357 1358 1359 /* various hacks, don't look :) */ 1360 1361 /* deflateInit and inflateInit are macros to allow checking the zlib version 1362 * and the compiler's view of z_stream: 1363 */ 1364 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, 1365 const char *version, int stream_size)); 1366 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, 1367 const char *version, int stream_size)); 1368 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, 1369 int windowBits, int memLevel, 1370 int strategy, const char *version, 1371 int stream_size)); 1372 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, 1373 const char *version, int stream_size)); 1374 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, 1375 unsigned char FAR *window, 1376 const char *version, 1377 int stream_size)); 1378 #define deflateInit(strm, level) \ 1379 deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) 1380 #define inflateInit(strm) \ 1381 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) 1382 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ 1383 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ 1384 (strategy), ZLIB_VERSION, sizeof(z_stream)) 1385 #define inflateInit2(strm, windowBits) \ 1386 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) 1387 #define inflateBackInit(strm, windowBits, window) \ 1388 inflateBackInit_((strm), (windowBits), (window), \ 1389 ZLIB_VERSION, sizeof(z_stream)) 1390 1391 1392 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) 1393 struct internal_state {int dummy;}; /* hack for buggy compilers */ 1394 #endif 1395 1396 ZEXTERN const char * ZEXPORT zError OF((int)); 1397 ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z)); 1398 ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); 1399 1400 #ifdef __cplusplus 1401 } 1402 #endif 1403 1404 #endif /* ZLIB_H */ 1405