1 /* 2 * This file is derived from zlib.h and zconf.h from the zlib-1.2.3 3 * distribution by Jean-loup Gailly and Mark Adler, with some additions 4 * by Paul Mackerras to aid in implementing Deflate compression and 5 * decompression for PPP packets. 6 */ 7 8 /* 9 * ==FILEVERSION 960122== 10 * 11 * This marker is used by the Linux installation script to determine 12 * whether an up-to-date version of this file is already installed. 13 */ 14 15 /* zlib.h -- interface of the 'zlib' general purpose compression library 16 version 1.2.3, July 18th, 2005 17 18 Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler 19 20 This software is provided 'as-is', without any express or implied 21 warranty. In no event will the authors be held liable for any damages 22 arising from the use of this software. 23 24 Permission is granted to anyone to use this software for any purpose, 25 including commercial applications, and to alter it and redistribute it 26 freely, subject to the following restrictions: 27 28 1. The origin of this software must not be misrepresented; you must not 29 claim that you wrote the original software. If you use this software 30 in a product, an acknowledgment in the product documentation would be 31 appreciated but is not required. 32 2. Altered source versions must be plainly marked as such, and must not be 33 misrepresented as being the original software. 34 3. This notice may not be removed or altered from any source distribution. 35 36 Jean-loup Gailly Mark Adler 37 jloup@gzip.org madler@alumni.caltech.edu 38 39 40 The data format used by the zlib library is described by RFCs (Request for 41 Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt 42 (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). 43 */ 44 45 #ifndef ZLIB_H 46 #define ZLIB_H 47 48 #ifdef __cplusplus 49 extern "C" { 50 #endif 51 52 #define ZLIB_VERSION "1.2.3" 53 #define ZLIB_VERNUM 0x1230 54 55 /* #include "zconf.h" */ /* included directly here */ 56 /* zconf.h -- configuration of the zlib compression library 57 * Copyright (C) 1995-2005 Jean-loup Gailly. 58 * For conditions of distribution and use, see copyright notice in zlib.h 59 */ 60 61 /* Begin of new zconf.h */ 62 /* 63 * If you *really* need a unique prefix for all types and library functions, 64 * compile with -DZ_PREFIX. The "standard" zlib should be compiled without it. 65 */ 66 #ifdef Z_PREFIX 67 # define deflateInit_ z_deflateInit_ 68 # define deflate z_deflate 69 # define deflateEnd z_deflateEnd 70 # define inflateInit_ z_inflateInit_ 71 # define inflate z_inflate 72 # define inflateEnd z_inflateEnd 73 # define deflateInit2_ z_deflateInit2_ 74 # define deflateSetDictionary z_deflateSetDictionary 75 # define deflateCopy z_deflateCopy 76 # define deflateReset z_deflateReset 77 # define deflateParams z_deflateParams 78 # define deflateBound z_deflateBound 79 # define deflatePrime z_deflatePrime 80 # define inflateInit2_ z_inflateInit2_ 81 # define inflateSetDictionary z_inflateSetDictionary 82 # define inflateSync z_inflateSync 83 # define inflateSyncPoint z_inflateSyncPoint 84 # define inflateCopy z_inflateCopy 85 # define inflateReset z_inflateReset 86 # define inflateBack z_inflateBack 87 # define inflateBackEnd z_inflateBackEnd 88 # define compress z_compress 89 # define compress2 z_compress2 90 # define compressBound z_compressBound 91 # define uncompress z_uncompress 92 # define adler32 z_adler32 93 # define crc32 z_crc32 94 # define get_crc_table z_get_crc_table 95 # define zError z_zError 96 97 # define alloc_func z_alloc_func 98 # define free_func z_free_func 99 # define in_func z_in_func 100 # define out_func z_out_func 101 # define Byte z_Byte 102 # define uInt z_uInt 103 # define uLong z_uLong 104 # define Bytef z_Bytef 105 # define charf z_charf 106 # define intf z_intf 107 # define uIntf z_uIntf 108 # define uLongf z_uLongf 109 # define voidpf z_voidpf 110 # define voidp z_voidp 111 #endif 112 113 #if defined(ZLIB_CONST) && !defined(z_const) 114 # define z_const const 115 #else 116 # define z_const 117 #endif 118 119 #if defined(__MSDOS__) && !defined(MSDOS) 120 # define MSDOS 121 #endif 122 #if (defined(OS_2) || defined(__OS2__)) && !defined(OS2) 123 # define OS2 124 #endif 125 #if defined(_WINDOWS) && !defined(WINDOWS) 126 # define WINDOWS 127 #endif 128 #if defined(_WIN32) || defined(_WIN32_WCE) || defined(__WIN32__) 129 # ifndef WIN32 130 # define WIN32 131 # endif 132 #endif 133 #if (defined(MSDOS) || defined(OS2) || defined(WINDOWS)) && !defined(WIN32) 134 # if !defined(__GNUC__) && !defined(__FLAT__) && !defined(__386__) 135 # ifndef SYS16BIT 136 # define SYS16BIT 137 # endif 138 # endif 139 #endif 140 141 /* 142 * Compile with -DMAXSEG_64K if the alloc function cannot allocate more 143 * than 64k bytes at a time (needed on systems with 16-bit int). 144 */ 145 #ifdef SYS16BIT 146 # define MAXSEG_64K 147 #endif 148 #ifdef MSDOS 149 # define UNALIGNED_OK 150 #endif 151 152 #ifdef __STDC_VERSION__ 153 # ifndef STDC 154 # define STDC 155 # endif 156 # if __STDC_VERSION__ >= 199901L 157 # ifndef STDC99 158 # define STDC99 159 # endif 160 # endif 161 #endif 162 #if !defined(STDC) && (defined(__STDC__) || defined(__cplusplus)) 163 # define STDC 164 #endif 165 #if !defined(STDC) && (defined(__GNUC__) || defined(__BORLANDC__)) 166 # define STDC 167 #endif 168 #if !defined(STDC) && (defined(MSDOS) || defined(WINDOWS) || defined(WIN32)) 169 # define STDC 170 #endif 171 #if !defined(STDC) && (defined(OS2) || defined(__HOS_AIX__)) 172 # define STDC 173 #endif 174 175 #if defined(__OS400__) && !defined(STDC) /* iSeries (formerly AS/400). */ 176 # define STDC 177 #endif 178 179 #ifndef STDC 180 # ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */ 181 # define const /* note: need a more gentle solution here */ 182 # endif 183 #endif 184 185 /* Some Mac compilers merge all .h files incorrectly: */ 186 #if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__) 187 # define NO_DUMMY_DECL 188 #endif 189 190 /* Maximum value for memLevel in deflateInit2 */ 191 #ifndef MAX_MEM_LEVEL 192 # ifdef MAXSEG_64K 193 # define MAX_MEM_LEVEL 8 194 # else 195 # define MAX_MEM_LEVEL 9 196 # endif 197 #endif 198 199 /* Maximum value for windowBits in deflateInit2 and inflateInit2. 200 * WARNING: reducing MAX_WBITS makes minigzip unable to extract .gz files 201 * created by gzip. (Files created by minigzip can still be extracted by 202 * gzip.) 203 */ 204 #ifndef MAX_WBITS 205 # define MAX_WBITS 15 /* 32K LZ77 window */ 206 #endif 207 208 /* The memory requirements for deflate are (in bytes): 209 (1 << (windowBits+2)) + (1 << (memLevel+9)) 210 that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values) 211 plus a few kilobytes for small objects. For example, if you want to reduce 212 the default memory requirements from 256K to 128K, compile with 213 make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7" 214 Of course this will generally degrade compression (there's no free lunch). 215 216 The memory requirements for inflate are (in bytes) 1 << windowBits 217 that is, 32K for windowBits=15 (default value) plus a few kilobytes 218 for small objects. 219 */ 220 221 /* Type declarations */ 222 223 #ifndef OF /* function prototypes */ 224 # ifdef STDC 225 # define OF(args) args 226 # else 227 # define OF(args) () 228 # endif 229 #endif 230 231 /* The following definitions for FAR are needed only for MSDOS mixed 232 * model programming (small or medium model with some far allocations). 233 * This was tested only with MSC; for other MSDOS compilers you may have 234 * to define NO_MEMCPY in zutil.h. If you don't need the mixed model, 235 * just define FAR to be empty. 236 */ 237 #ifdef SYS16BIT 238 # if defined(M_I86SM) || defined(M_I86MM) 239 /* MSC small or medium model */ 240 # define SMALL_MEDIUM 241 # ifdef _MSC_VER 242 # define FAR _far 243 # else 244 # define FAR far 245 # endif 246 # endif 247 # if (defined(__SMALL__) || defined(__MEDIUM__)) 248 /* Turbo C small or medium model */ 249 # define SMALL_MEDIUM 250 # ifdef __BORLANDC__ 251 # define FAR _far 252 # else 253 # define FAR far 254 # endif 255 # endif 256 #endif 257 258 #if defined(WINDOWS) || defined(WIN32) 259 /* If building or using zlib as a DLL, define ZLIB_DLL. 260 * This is not mandatory, but it offers a little performance increase. 261 */ 262 # ifdef ZLIB_DLL 263 # if defined(WIN32) && (!defined(__BORLANDC__) || (__BORLANDC__ >= 0x500)) 264 # ifdef ZLIB_INTERNAL 265 # define ZEXTERN extern __declspec(dllexport) 266 # else 267 # define ZEXTERN extern __declspec(dllimport) 268 # endif 269 # endif 270 # endif /* ZLIB_DLL */ 271 /* If building or using zlib with the WINAPI/WINAPIV calling convention, 272 * define ZLIB_WINAPI. 273 * Caution: the standard ZLIB1.DLL is NOT compiled using ZLIB_WINAPI. 274 */ 275 # ifdef ZLIB_WINAPI 276 # ifdef FAR 277 # undef FAR 278 # endif 279 # include <windows.h> 280 /* No need for _export, use ZLIB.DEF instead. */ 281 /* For complete Windows compatibility, use WINAPI, not __stdcall. */ 282 # define ZEXPORT WINAPI 283 # ifdef WIN32 284 # define ZEXPORTVA WINAPIV 285 # else 286 # define ZEXPORTVA FAR CDECL 287 # endif 288 # endif 289 #endif 290 291 #if defined (__BEOS__) 292 # ifdef ZLIB_DLL 293 # ifdef ZLIB_INTERNAL 294 # define ZEXPORT __declspec(dllexport) 295 # define ZEXPORTVA __declspec(dllexport) 296 # else 297 # define ZEXPORT __declspec(dllimport) 298 # define ZEXPORTVA __declspec(dllimport) 299 # endif 300 # endif 301 #endif 302 303 #ifndef ZEXTERN 304 # define ZEXTERN extern 305 #endif 306 #ifndef ZEXPORT 307 # define ZEXPORT 308 #endif 309 #ifndef ZEXPORTVA 310 # define ZEXPORTVA 311 #endif 312 313 #ifndef FAR 314 # define FAR 315 #endif 316 317 #if !defined(__MACTYPES__) 318 typedef unsigned char Byte; /* 8 bits */ 319 #endif 320 typedef unsigned int uInt; /* 16 bits or more */ 321 typedef unsigned long uLong; /* 32 bits or more */ 322 323 #ifdef SMALL_MEDIUM 324 /* Borland C/C++ and some old MSC versions ignore FAR inside typedef */ 325 # define Bytef Byte FAR 326 #else 327 typedef Byte FAR Bytef; 328 #endif 329 typedef char FAR charf; 330 typedef int FAR intf; 331 typedef uInt FAR uIntf; 332 typedef uLong FAR uLongf; 333 334 #ifdef STDC 335 typedef void const *voidpc; 336 typedef void FAR *voidpf; 337 typedef void *voidp; 338 #else 339 typedef Byte const *voidpc; 340 typedef Byte FAR *voidpf; 341 typedef Byte *voidp; 342 #endif 343 344 # ifdef VMS 345 # include <unixio.h> /* for off_t */ 346 # endif 347 # define z_off_t off_t 348 #ifndef SEEK_SET 349 # define SEEK_SET 0 /* Seek from beginning of file. */ 350 # define SEEK_CUR 1 /* Seek from current position. */ 351 # define SEEK_END 2 /* Set file pointer to EOF plus "offset" */ 352 #endif 353 #ifndef z_off_t 354 # define z_off_t long 355 #endif 356 357 #if defined(__OS400__) 358 # define NO_vsnprintf 359 #endif 360 361 #if defined(__MVS__) 362 # define NO_vsnprintf 363 # ifdef FAR 364 # undef FAR 365 # endif 366 #endif 367 368 /* MVS linker does not support external names larger than 8 bytes */ 369 #if defined(__MVS__) 370 # pragma map(deflateInit_,"DEIN") 371 # pragma map(deflateInit2_,"DEIN2") 372 # pragma map(deflateEnd,"DEEND") 373 # pragma map(deflateBound,"DEBND") 374 # pragma map(inflateInit_,"ININ") 375 # pragma map(inflateInit2_,"ININ2") 376 # pragma map(inflateEnd,"INEND") 377 # pragma map(inflateSync,"INSY") 378 # pragma map(inflateSetDictionary,"INSEDI") 379 # pragma map(compressBound,"CMBND") 380 # pragma map(inflate_table,"INTABL") 381 # pragma map(inflate_fast,"INFA") 382 # pragma map(inflate_copyright,"INCOPY") 383 #endif 384 /* End of new zconf.h */ 385 386 /* 387 The 'zlib' compression library provides in-memory compression and 388 decompression functions, including integrity checks of the uncompressed 389 data. This version of the library supports only one compression method 390 (deflation) but other algorithms will be added later and will have the same 391 stream interface. 392 393 Compression can be done in a single step if the buffers are large 394 enough (for example if an input file is mmap'ed), or can be done by 395 repeated calls of the compression function. In the latter case, the 396 application must provide more input and/or consume the output 397 (providing more output space) before each call. 398 399 The compressed data format used by default by the in-memory functions is 400 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped 401 around a deflate stream, which is itself documented in RFC 1951. 402 403 The library also supports reading and writing files in gzip (.gz) format 404 with an interface similar to that of stdio using the functions that start 405 with "gz". The gzip format is different from the zlib format. gzip is a 406 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. 407 408 This library can optionally read and write gzip streams in memory as well. 409 410 The zlib format was designed to be compact and fast for use in memory 411 and on communications channels. The gzip format was designed for single- 412 file compression on file systems, has a larger header than zlib to maintain 413 directory information, and uses a different, slower check method than zlib. 414 415 The library does not install any signal handler. The decoder checks 416 the consistency of the compressed data, so the library should never 417 crash even in case of corrupted input. 418 */ 419 420 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); 421 typedef void (*free_func) OF((voidpf opaque, voidpf address, uInt size)); 422 typedef void (*cb_func) OF((Bytef *buf, uInt len)); 423 424 struct internal_state; 425 426 typedef struct z_stream_s { 427 Bytef *next_in; /* next input byte */ 428 uInt avail_in; /* number of bytes available at next_in */ 429 uLong total_in; /* total nb of input bytes read so far */ 430 Bytef *next_out; /* next output byte should be put there */ 431 uInt avail_out; /* remaining free space at next_out */ 432 uLong total_out; /* total nb of bytes output so far */ 433 char *msg; /* last error message, NULL if no error */ 434 struct internal_state FAR *state; /* not visible by applications */ 435 alloc_func zalloc; /* used to allocate the internal state */ 436 free_func zfree; /* used to free the internal state */ 437 voidpf opaque; /* private data object passed to zalloc and zfree */ 438 int data_type; /* best guess about the data type: 439 binary or text */ 440 cb_func outcb; /* called regularly just before blocks of output */ 441 uLong adler; /* adler32 value of the uncompressed data */ 442 uLong reserved; /* reserved for future use */ 443 } z_stream; 444 445 typedef z_stream FAR *z_streamp; 446 447 /* 448 gzip header information passed to and from zlib routines. See RFC 1952 449 for more details on the meanings of these fields. 450 */ 451 typedef struct gz_header_s { 452 int text; /* true if compressed data believed to be text */ 453 uLong time; /* modification time */ 454 int xflags; /* extra flags (not used when writing a gzip file) */ 455 int os; /* operating system */ 456 Bytef *extra; /* pointer to extra field or Z_NULL if none */ 457 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */ 458 uInt extra_max; /* space at extra (only when reading header) */ 459 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ 460 uInt name_max; /* space at name (only when reading header) */ 461 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */ 462 uInt comm_max; /* space at comment (only when reading header) */ 463 int hcrc; /* true if there was or will be a header crc */ 464 int done; /* true when done reading gzip header (not used 465 when writing a gzip file) */ 466 } gz_header; 467 468 typedef gz_header FAR *gz_headerp; 469 470 /* constants */ 471 #define Z_NO_FLUSH 0 472 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ 473 #define Z_SYNC_FLUSH 2 474 #define Z_FULL_FLUSH 3 475 #define Z_FINISH 4 476 #define Z_BLOCK 5 477 /* Allowed flush values; see deflate() and inflate() below for details */ 478 479 #define Z_OK 0 480 #define Z_STREAM_END 1 481 #define Z_NEED_DICT 2 482 #define Z_ERRNO (-1) 483 #define Z_STREAM_ERROR (-2) 484 #define Z_DATA_ERROR (-3) 485 #define Z_MEM_ERROR (-4) 486 #define Z_BUF_ERROR (-5) 487 #define Z_VERSION_ERROR (-6) 488 /* Return codes for the compression/decompression functions. Negative 489 * values are errors, positive values are used for special but normal events. 490 */ 491 492 #define Z_NO_COMPRESSION 0 493 #define Z_BEST_SPEED 1 494 #define Z_BEST_COMPRESSION 9 495 #define Z_DEFAULT_COMPRESSION (-1) 496 /* compression levels */ 497 498 #define Z_FILTERED 1 499 #define Z_HUFFMAN_ONLY 2 500 #define Z_RLE 3 501 #define Z_FIXED 4 502 #define Z_DEFAULT_STRATEGY 0 503 /* compression strategy; see deflateInit2() below for details */ 504 505 #define Z_BINARY 0 506 #define Z_TEXT 1 507 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ 508 #define Z_UNKNOWN 2 509 /* Possible values of the data_type field (though see inflate()) */ 510 511 #define Z_DEFLATED 8 512 /* The deflate compression method (the only one supported in this version) */ 513 514 #define Z_NULL (void *)0 /* for initializing zalloc, zfree, opaque */ 515 516 /* basic functions */ 517 518 /* The application can compare zlibVersion and ZLIB_VERSION for consistency. 519 If the first character differs, the library code actually used is 520 not compatible with the zlib.h header file used by the application. 521 This check is automatically made by deflateInit and inflateInit. 522 */ 523 524 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); 525 ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, 526 const char *version, int stream_size)); 527 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); 528 ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, 529 int windowBits, int memLevel, 530 int strategy, const char *version, 531 int stream_size)); 532 ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); 533 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, 534 const Bytef *dictionary, 535 uInt dictLength)); 536 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, 537 gz_headerp head)); 538 ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, 539 int bits, 540 int value)); 541 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, 542 int level, 543 int strategy)); 544 ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, 545 int good_length, 546 int max_lazy, 547 int nice_length, 548 int max_chain)); 549 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, 550 uLong sourceLen)); 551 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, 552 z_streamp source)); 553 554 555 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, 556 const char *version, int stream_size)); 557 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); 558 /* 559 inflate decompresses as much data as possible, and stops when the input 560 buffer becomes empty or the output buffer becomes full. It may introduce 561 some output latency (reading input without producing any output) except when 562 forced to flush. 563 564 The detailed semantics are as follows. inflate performs one or both of the 565 following actions: 566 567 - Decompress more input starting at next_in and update next_in and avail_in 568 accordingly. If not all input can be processed (because there is not 569 enough room in the output buffer), next_in is updated and processing 570 will resume at this point for the next call of inflate(). 571 572 - Provide more output starting at next_out and update next_out and avail_out 573 accordingly. inflate() provides as much output as possible, until there 574 is no more input data or no more space in the output buffer (see below 575 about the flush parameter). 576 577 Before the call of inflate(), the application should ensure that at least 578 one of the actions is possible, by providing more input and/or consuming 579 more output, and updating the next_* and avail_* values accordingly. 580 The application can consume the uncompressed output when it wants, for 581 example when the output buffer is full (avail_out == 0), or after each 582 call of inflate(). If inflate returns Z_OK and with zero avail_out, it 583 must be called again after making room in the output buffer because there 584 might be more output pending. 585 586 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, 587 Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much 588 output as possible to the output buffer. Z_BLOCK requests that inflate() stop 589 if and when it gets to the next deflate block boundary. When decoding the 590 zlib or gzip format, this will cause inflate() to return immediately after 591 the header and before the first block. When doing a raw inflate, inflate() 592 will go ahead and process the first block, and will return when it gets to 593 the end of that block, or when it runs out of data. 594 595 The Z_BLOCK option assists in appending to or combining deflate streams. 596 Also to assist in this, on return inflate() will set strm->data_type to the 597 number of unused bits in the last byte taken from strm->next_in, plus 64 598 if inflate() is currently decoding the last block in the deflate stream, 599 plus 128 if inflate() returned immediately after decoding an end-of-block 600 code or decoding the complete header up to just before the first byte of the 601 deflate stream. The end-of-block will not be indicated until all of the 602 uncompressed data from that block has been written to strm->next_out. The 603 number of unused bits may in general be greater than seven, except when 604 bit 7 of data_type is set, in which case the number of unused bits will be 605 less than eight. 606 607 inflate() should normally be called until it returns Z_STREAM_END or an 608 error. However if all decompression is to be performed in a single step 609 (a single call of inflate), the parameter flush should be set to 610 Z_FINISH. In this case all pending input is processed and all pending 611 output is flushed; avail_out must be large enough to hold all the 612 uncompressed data. (The size of the uncompressed data may have been saved 613 by the compressor for this purpose.) The next operation on this stream must 614 be inflateEnd to deallocate the decompression state. The use of Z_FINISH 615 is never required, but can be used to inform inflate that a faster approach 616 may be used for the single inflate() call. 617 618 In this implementation, inflate() always flushes as much output as 619 possible to the output buffer, and always uses the faster approach on the 620 first call. So the only effect of the flush parameter in this implementation 621 is on the return value of inflate(), as noted below, or when it returns early 622 because Z_BLOCK is used. 623 624 If a preset dictionary is needed after this call (see inflateSetDictionary 625 below), inflate sets strm->adler to the adler32 checksum of the dictionary 626 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets 627 strm->adler to the adler32 checksum of all output produced so far (that is, 628 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described 629 below. At the end of the stream, inflate() checks that its computed adler32 630 checksum is equal to that saved by the compressor and returns Z_STREAM_END 631 only if the checksum is correct. 632 633 inflate() will decompress and check either zlib-wrapped or gzip-wrapped 634 deflate data. The header type is detected automatically. Any information 635 contained in the gzip header is not retained, so applications that need that 636 information should instead use raw inflate, see inflateInit2() below, or 637 inflateBack() and perform their own processing of the gzip header and 638 trailer. 639 640 inflate() returns Z_OK if some progress has been made (more input processed 641 or more output produced), Z_STREAM_END if the end of the compressed data has 642 been reached and all uncompressed output has been produced, Z_NEED_DICT if a 643 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was 644 corrupted (input stream not conforming to the zlib format or incorrect check 645 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example 646 if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, 647 Z_BUF_ERROR if no progress is possible or if there was not enough room in the 648 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and 649 inflate() can be called again with more input and more output space to 650 continue decompressing. If Z_DATA_ERROR is returned, the application may then 651 call inflateSync() to look for a good compression block if a partial recovery 652 of the data is desired. 653 */ 654 655 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); 656 /* 657 All dynamically allocated data structures for this stream are freed. 658 This function discards any unprocessed input and does not flush any 659 pending output. 660 661 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state 662 was inconsistent. In the error case, msg may be set but then points to a 663 static string (which must not be deallocated). 664 */ 665 666 /* Advanced functions */ 667 668 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); 669 670 /* utility functions */ 671 672 /* 673 The following utility functions are implemented on top of the 674 basic stream-oriented functions. To simplify the interface, some 675 default options are assumed (compression level and memory usage, 676 standard memory allocation functions). The source code of these 677 utility functions can easily be modified if you need special options. 678 */ 679 680 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); 681 /* 682 Update a running Adler-32 checksum with the bytes buf[0..len-1] and 683 return the updated checksum. If buf is NULL, this function returns 684 the required initial value for the checksum. 685 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed 686 much faster. Usage example: 687 688 uLong adler = adler32(0L, Z_NULL, 0); 689 690 while (read_buffer(buffer, length) != EOF) { 691 adler = adler32(adler, buffer, length); 692 } 693 if (adler != original_adler) error(); 694 */ 695 696 /* 697 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 698 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for 699 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of 700 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. 701 */ 702 703 ZEXTERN uInt ZEXPORT crc32 OF((uInt crc, const Bytef *buf, uInt len)); 704 /* 705 Update a running CRC-32 with the bytes buf[0..len-1] and return the 706 updated CRC-32. If buf is NULL, this function returns the required initial 707 value for the for the crc. Pre- and post-conditioning (one's complement) is 708 performed within this function so it shouldn't be done by the application. 709 Usage example: 710 711 uLong crc = crc32(0L, Z_NULL, 0); 712 713 while (read_buffer(buffer, length) != EOF) { 714 crc = crc32(crc, buffer, length); 715 } 716 if (crc != original_crc) error(); 717 */ 718 719 ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, 720 const Bytef *source, uLong sourceLen)); 721 /* 722 Decompresses the source buffer into the destination buffer. sourceLen is 723 the byte length of the source buffer. Upon entry, destLen is the total size 724 of the destination buffer, which must be large enough to hold the entire 725 uncompressed data. (The size of the uncompressed data must have been saved 726 previously by the compressor and transmitted to the decompressor by some 727 mechanism outside the scope of this compression library.) Upon exit, destLen 728 is the actual size of the uncompressed data. 729 730 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not 731 enough memory, Z_BUF_ERROR if there was not enough room in the output 732 buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In 733 the case where there is not enough room, uncompress() will fill the output 734 buffer with the uncompressed data up to that point. 735 */ 736 737 ZEXTERN int ZEXPORT uncompress2 OF((Bytef *dest, uLongf *destLen, 738 const Bytef *source, uLong *sourceLen)); 739 /* 740 Same as uncompress, except that sourceLen is a pointer, where the 741 length of the source is *sourceLen. On return, *sourceLen is the number of 742 source bytes consumed. 743 */ 744 745 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, 746 const char *version, int stream_size)); 747 #define inflateInit(strm) \ 748 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) 749 #define inflateInit2(strm, windowBits) \ 750 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) 751 752 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) 753 struct internal_state {int dummy;}; /* hack for buggy compilers */ 754 #endif 755 756 extern void *gzalloc(void *, unsigned, unsigned); 757 extern void gzfree(void *, void *, unsigned); 758 759 #ifdef __cplusplus 760 } 761 #endif 762 763 #endif /* ZLIB_H */ 764