1/* $NetBSD: zlib.h,v 1.13 2009/03/14 14:46:10 dsl Exp $ */ 2 3/* zlib.h -- interface of the 'zlib' general purpose compression library 4 version 1.1.4, March 11th, 2002 5 6 Copyright (C) 1995-2002 Jean-loup Gailly and Mark Adler 7 8 This software is provided 'as-is', without any express or implied 9 warranty. In no event will the authors be held liable for any damages 10 arising from the use of this software. 11 12 Permission is granted to anyone to use this software for any purpose, 13 including commercial applications, and to alter it and redistribute it 14 freely, subject to the following restrictions: 15 16 1. The origin of this software must not be misrepresented; you must not 17 claim that you wrote the original software. If you use this software 18 in a product, an acknowledgment in the product documentation would be 19 appreciated but is not required. 20 2. Altered source versions must be plainly marked as such, and must not be 21 misrepresented as being the original software. 22 3. This notice may not be removed or altered from any source distribution. 23 24 Jean-loup Gailly Mark Adler 25 jloup@gzip.org madler@alumni.caltech.edu 26 27 28 The data format used by the zlib library is described by RFCs (Request for 29 Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt 30 (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). 31*/ 32 33#ifndef _NET_ZLIB_H_ 34#define _NET_ZLIB_H_ 35 36#ifdef __NetBSD__ 37#include <sys/cdefs.h> 38#endif 39 40/* +++ zconf.h */ 41/* zconf.h -- configuration of the zlib compression library 42 * Copyright (C) 1995-2002 Jean-loup Gailly. 43 * For conditions of distribution and use, see copyright notice in zlib.h 44 */ 45 46/* @(#) $Id: zlib.h,v 1.14 2009/03/25 01:26:12 darran Exp $ */ 47 48#ifndef ZCONF_H 49#define ZCONF_H 50 51/* 52 * Warning: This file pollutes the user's namespace with: 53 * Byte Bytef EXPORT FAR OF STDC 54 * charf intf uInt uIntf uLong uLonf 55 * Programs using this library appear to expect those... 56 */ 57 58#include <sys/types.h> 59 60/* 61 * If you *really* need a unique prefix for all types and library functions, 62 * compile with -DZ_PREFIX. The "standard" zlib should be compiled without it. 63 */ 64#ifdef Z_PREFIX 65# define deflateInit_ z_deflateInit_ 66# define deflate z_deflate 67# define deflateEnd z_deflateEnd 68# define inflateInit_ z_inflateInit_ 69# define inflate z_inflate 70# define inflateEnd z_inflateEnd 71# define deflateInit2_ z_deflateInit2_ 72# define deflateSetDictionary z_deflateSetDictionary 73# define deflateCopy z_deflateCopy 74# define deflateReset z_deflateReset 75# define deflateParams z_deflateParams 76# define inflateInit2_ z_inflateInit2_ 77# define inflateSetDictionary z_inflateSetDictionary 78# define inflateSync z_inflateSync 79# define inflateSyncPoint z_inflateSyncPoint 80# define inflateReset z_inflateReset 81# define compress z_compress 82# define compress2 z_compress2 83# define uncompress z_uncompress 84# define adler32 z_adler32 85# define crc32 z_crc32 86# define get_crc_table z_get_crc_table 87 88# define Byte z_Byte 89# define uInt z_uInt 90# define uLong z_uLong 91# define Bytef z_Bytef 92# define charf z_charf 93# define intf z_intf 94# define uIntf z_uIntf 95# define uLongf z_uLongf 96# define voidpf z_voidpf 97# define voidp z_voidp 98#endif 99 100#ifndef __32BIT__ 101/* Don't be alarmed; this just means we have at least 32-bits */ 102# define __32BIT__ 103#endif 104 105/* 106 * Compile with -DMAXSEG_64K if the alloc function cannot allocate more 107 * than 64k bytes at a time (needed on systems with 16-bit int). 108 */ 109#if defined(MSDOS) && !defined(__32BIT__) 110# define MAXSEG_64K 111#endif 112 113#if 0 114/* XXX: Are there machines where we should define this? m68k? */ 115# define UNALIGNED_OK 116#endif 117 118#if (defined(__STDC__) || defined(__cplusplus)) && !defined(STDC) 119/* XXX: Look out - this is used in zutil.h and elsewhere... */ 120# define STDC 121#endif 122#if defined(__STDC__) || defined(__cplusplus) || defined(__OS2__) 123# ifndef STDC 124# define STDC 125# endif 126#endif 127 128#ifndef STDC 129# ifndef const 130# define const 131# endif 132#endif 133 134/* Some Mac compilers merge all .h files incorrectly: */ 135#if defined(__MWERKS__) || defined(applec) ||defined(THINK_C) ||defined(__SC__) 136# define NO_DUMMY_DECL 137#endif 138 139/* Old Borland C incorrectly complains about missing returns: */ 140#if defined(__BORLANDC__) && (__BORLANDC__ < 0x500) 141# define NEED_DUMMY_RETURN 142#endif 143 144 145/* Maximum value for memLevel in deflateInit2 */ 146#ifndef MAX_MEM_LEVEL 147# ifdef MAXSEG_64K 148# define MAX_MEM_LEVEL 8 149# else 150# define MAX_MEM_LEVEL 9 151# endif 152#endif 153 154/* Maximum value for windowBits in deflateInit2 and inflateInit2. 155 * WARNING: reducing MAX_WBITS makes minigzip unable to extract .gz files 156 * created by gzip. (Files created by minigzip can still be extracted by 157 * gzip.) 158 */ 159#ifndef MAX_WBITS 160# define MAX_WBITS 15 /* 32K LZ77 window */ 161#endif 162 163/* The memory requirements for deflate are (in bytes): 164 (1 << (windowBits+2)) + (1 << (memLevel+9)) 165 that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values) 166 plus a few kilobytes for small objects. For example, if you want to reduce 167 the default memory requirements from 256K to 128K, compile with 168 make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7" 169 Of course this will generally degrade compression (there's no free lunch). 170 171 The memory requirements for inflate are (in bytes) 1 << windowBits 172 that is, 32K for windowBits=15 (default value) plus a few kilobytes 173 for small objects. 174*/ 175 176 /* Type declarations */ 177 178#ifndef __P /* function prototypes */ 179# ifdef STDC 180# define __P(args) args 181# else 182# define __P(args) () 183# endif 184#endif 185 186/* The following definitions for FAR are needed only for MSDOS mixed 187 * model programming (small or medium model with some far allocations). 188 * This was tested only with MSC; for other MSDOS compilers you may have 189 * to define NO_MEMCPY in zutil.h. If you don't need the mixed model, 190 * just define FAR to be empty. 191 */ 192#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(__32BIT__) 193 /* MSC small or medium model */ 194# define SMALL_MEDIUM 195# ifdef _MSC_VER 196# define FAR _far 197# else 198# define FAR far 199# endif 200#endif 201#if defined(__BORLANDC__) && (defined(__SMALL__) || defined(__MEDIUM__)) 202# ifndef __32BIT__ 203# define SMALL_MEDIUM 204# define FAR _far 205# endif 206#endif 207 208/* Compile with -DZLIB_DLL for Windows DLL support */ 209#if defined(ZLIB_DLL) 210# if defined(_WINDOWS) || defined(WINDOWS) 211# ifdef FAR 212# undef FAR 213# endif 214# include <windows.h> 215# define ZEXPORT WINAPI 216# ifdef WIN32 217# define ZEXPORTVA WINAPIV 218# else 219# define ZEXPORTVA FAR _cdecl _export 220# endif 221# endif 222# if defined (__BORLANDC__) 223# if (__BORLANDC__ >= 0x0500) && defined (WIN32) 224# include <windows.h> 225# define ZEXPORT __declspec(dllexport) WINAPI 226# define ZEXPORTRVA __declspec(dllexport) WINAPIV 227# else 228# if defined (_Windows) && defined (__DLL__) 229# define ZEXPORT _export 230# define ZEXPORTVA _export 231# endif 232# endif 233# endif 234#endif 235 236#if defined (__BEOS__) 237# if defined (ZLIB_DLL) 238# define ZEXTERN extern __declspec(dllexport) 239# else 240# define ZEXTERN extern __declspec(dllimport) 241# endif 242#endif 243 244#ifndef ZEXPORT 245# define ZEXPORT 246#endif 247#ifndef ZEXPORTVA 248# define ZEXPORTVA 249#endif 250#ifndef ZEXTERN 251# define ZEXTERN extern 252#endif 253 254#ifndef FAR 255# define FAR 256#endif 257 258#if !defined(MACOS) && !defined(TARGET_OS_MAC) 259typedef unsigned char Byte; /* 8 bits */ 260#endif 261typedef unsigned int uInt; /* 16 bits or more */ 262typedef unsigned long uLong; /* 32 bits or more */ 263 264#ifdef SMALL_MEDIUM 265 /* Borland C/C++ and some old MSC versions ignore FAR inside typedef */ 266# define Bytef Byte FAR 267#else 268 typedef Byte FAR Bytef; 269#endif 270typedef char FAR charf; 271typedef int FAR intf; 272typedef uInt FAR uIntf; 273typedef uLong FAR uLongf; 274 275#ifdef STDC 276 typedef void FAR *voidpf; 277 typedef void *voidp; 278#else 279 typedef Byte FAR *voidpf; 280 typedef Byte *voidp; 281#endif 282 283#if (defined(HAVE_UNISTD_H) || defined(__NetBSD__)) && !defined(_KERNEL) 284# include <sys/types.h> /* for off_t */ 285# include <unistd.h> /* for SEEK_* and off_t */ 286# define z_off_t off_t 287#endif 288#ifndef SEEK_SET 289# define SEEK_SET 0 /* Seek from beginning of file. */ 290# define SEEK_CUR 1 /* Seek from current position. */ 291# define SEEK_END 2 /* Set file pointer to EOF plus "offset" */ 292#endif 293#ifndef z_off_t 294# define z_off_t long 295#endif 296 297/* MVS linker does not support external names larger than 8 bytes */ 298#if defined(__MVS__) 299# pragma map(deflateInit_,"DEIN") 300# pragma map(deflateInit2_,"DEIN2") 301# pragma map(deflateEnd,"DEEND") 302# pragma map(inflateInit_,"ININ") 303# pragma map(inflateInit2_,"ININ2") 304# pragma map(inflateEnd,"INEND") 305# pragma map(inflateSync,"INSY") 306# pragma map(inflateSetDictionary,"INSEDI") 307# pragma map(inflate_blocks,"INBL") 308# pragma map(inflate_blocks_new,"INBLNE") 309# pragma map(inflate_blocks_free,"INBLFR") 310# pragma map(inflate_blocks_reset,"INBLRE") 311# pragma map(inflate_codes_free,"INCOFR") 312# pragma map(inflate_codes,"INCO") 313# pragma map(inflate_fast,"INFA") 314# pragma map(inflate_flush,"INFLU") 315# pragma map(inflate_mask,"INMA") 316# pragma map(inflate_set_dictionary,"INSEDI2") 317# pragma map(inflate_copyright,"INCOPY") 318# pragma map(inflate_trees_bits,"INTRBI") 319# pragma map(inflate_trees_dynamic,"INTRDY") 320# pragma map(inflate_trees_fixed,"INTRFI") 321# pragma map(inflate_trees_free,"INTRFR") 322#endif 323 324#endif /* !ZCONF_H */ 325/* --- zconf.h */ 326 327#ifndef ZLIB_H 328#define ZLIB_H 329#ifdef __cplusplus 330extern "C" { 331#endif 332 333#define ZLIB_VERSION "1.1.4" 334 335/* 336 The 'zlib' compression library provides in-memory compression and 337 decompression functions, including integrity checks of the uncompressed 338 data. This version of the library supports only one compression method 339 (deflation) but other algorithms will be added later and will have the same 340 stream interface. 341 342 Compression can be done in a single step if the buffers are large 343 enough (for example if an input file is mmap'ed), or can be done by 344 repeated calls of the compression function. In the latter case, the 345 application must provide more input and/or consume the output 346 (providing more output space) before each call. 347 348 The library also supports reading and writing files in gzip (.gz) format 349 with an interface similar to that of stdio. 350 351 The library does not install any signal handler. The decoder checks 352 the consistency of the compressed data, so the library should never 353 crash even in case of corrupted input. 354*/ 355 356typedef voidpf (*alloc_func)(voidpf, uInt, uInt); 357typedef void (*free_func)(voidpf, voidpf); 358 359struct internal_state; 360 361typedef struct z_stream_s { 362 Bytef *next_in; /* next input byte */ 363 uInt avail_in; /* number of bytes available at next_in */ 364 uLong total_in; /* total nb of input bytes read so far */ 365 366 Bytef *next_out; /* next output byte should be put there */ 367 uInt avail_out; /* remaining free space at next_out */ 368 uLong total_out; /* total nb of bytes output so far */ 369 370 const char *msg; /* last error message, NULL if no error */ 371 struct internal_state FAR *state; /* not visible by applications */ 372 373 alloc_func zalloc; /* used to allocate the internal state */ 374 free_func zfree; /* used to free the internal state */ 375 voidpf opaque; /* private data object passed to zalloc and zfree */ 376 377 int data_type; /* best guess about the data type: ascii or binary */ 378 uLong adler; /* adler32 value of the uncompressed data */ 379 uLong reserved; /* reserved for future use */ 380} z_stream; 381 382typedef z_stream FAR *z_streamp; 383 384/* 385 The application must update next_in and avail_in when avail_in has 386 dropped to zero. It must update next_out and avail_out when avail_out 387 has dropped to zero. The application must initialize zalloc, zfree and 388 opaque before calling the init function. All other fields are set by the 389 compression library and must not be updated by the application. 390 391 The opaque value provided by the application will be passed as the first 392 parameter for calls of zalloc and zfree. This can be useful for custom 393 memory management. The compression library attaches no meaning to the 394 opaque value. 395 396 zalloc must return Z_NULL if there is not enough memory for the object. 397 If zlib is used in a multi-threaded application, zalloc and zfree must be 398 thread safe. 399 400 On 16-bit systems, the functions zalloc and zfree must be able to allocate 401 exactly 65536 bytes, but will not be required to allocate more than this 402 if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, 403 pointers returned by zalloc for objects of exactly 65536 bytes *must* 404 have their offset normalized to zero. The default allocation function 405 provided by this library ensures this (see zutil.c). To reduce memory 406 requirements and avoid any allocation of 64K objects, at the expense of 407 compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). 408 409 The fields total_in and total_out can be used for statistics or 410 progress reports. After compression, total_in holds the total size of 411 the uncompressed data and may be saved for use in the decompressor 412 (particularly if the decompressor wants to decompress everything in 413 a single step). 414*/ 415 416 /* constants */ 417 418#define Z_NO_FLUSH 0 419#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ 420#define Z_PACKET_FLUSH 2 421#define Z_SYNC_FLUSH 3 422#define Z_FULL_FLUSH 4 423#define Z_FINISH 5 424/* Allowed flush values; see deflate() below for details */ 425 426#define Z_OK 0 427#define Z_STREAM_END 1 428#define Z_NEED_DICT 2 429#define Z_ERRNO (-1) 430#define Z_STREAM_ERROR (-2) 431#define Z_DATA_ERROR (-3) 432#define Z_MEM_ERROR (-4) 433#define Z_BUF_ERROR (-5) 434#define Z_VERSION_ERROR (-6) 435/* Return codes for the compression/decompression functions. Negative 436 * values are errors, positive values are used for special but normal events. 437 */ 438 439#define Z_NO_COMPRESSION 0 440#define Z_BEST_SPEED 1 441#define Z_BEST_COMPRESSION 9 442#define Z_DEFAULT_COMPRESSION (-1) 443/* compression levels */ 444 445#define Z_FILTERED 1 446#define Z_HUFFMAN_ONLY 2 447#define Z_DEFAULT_STRATEGY 0 448/* compression strategy; see deflateInit2() below for details */ 449 450#define Z_BINARY 0 451#define Z_ASCII 1 452#define Z_UNKNOWN 2 453/* Possible values of the data_type field */ 454 455#define Z_DEFLATED 8 456/* The deflate compression method (the only one supported in this version) */ 457 458#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ 459 460#define zlib_version zlibVersion() 461/* for compatibility with versions < 1.0.2 */ 462 463 /* basic functions */ 464 465ZEXTERN const char * ZEXPORT zlibVersion(void); 466/* The application can compare zlibVersion and ZLIB_VERSION for consistency. 467 If the first character differs, the library code actually used is 468 not compatible with the zlib.h header file used by the application. 469 This check is automatically made by deflateInit and inflateInit. 470 */ 471 472/* 473ZEXTERN int ZEXPORT deflateInit(z_streamp, int); 474 475 Initializes the internal stream state for compression. The fields 476 zalloc, zfree and opaque must be initialized before by the caller. 477 If zalloc and zfree are set to Z_NULL, deflateInit updates them to 478 use default allocation functions. 479 480 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: 481 1 gives best speed, 9 gives best compression, 0 gives no compression at 482 all (the input data is simply copied a block at a time). 483 Z_DEFAULT_COMPRESSION requests a default compromise between speed and 484 compression (currently equivalent to level 6). 485 486 deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not 487 enough memory, Z_STREAM_ERROR if level is not a valid compression level, 488 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible 489 with the version assumed by the caller (ZLIB_VERSION). 490 msg is set to null if there is no error message. deflateInit does not 491 perform any compression: this will be done by deflate(). 492*/ 493 494 495ZEXTERN int ZEXPORT deflate(z_streamp, int); 496/* 497 deflate compresses as much data as possible, and stops when the input 498 buffer becomes empty or the output buffer becomes full. It may introduce some 499 output latency (reading input without producing any output) except when 500 forced to flush. 501 502 The detailed semantics are as follows. deflate performs one or both of the 503 following actions: 504 505 - Compress more input starting at next_in and update next_in and avail_in 506 accordingly. If not all input can be processed (because there is not 507 enough room in the output buffer), next_in and avail_in are updated and 508 processing will resume at this point for the next call of deflate(). 509 510 - Provide more output starting at next_out and update next_out and avail_out 511 accordingly. This action is forced if the parameter flush is non zero. 512 Forcing flush frequently degrades the compression ratio, so this parameter 513 should be set only when necessary (in interactive applications). 514 Some output may be provided even if flush is not set. 515 516 Before the call of deflate(), the application should ensure that at least 517 one of the actions is possible, by providing more input and/or consuming 518 more output, and updating avail_in or avail_out accordingly; avail_out 519 should never be zero before the call. The application can consume the 520 compressed output when it wants, for example when the output buffer is full 521 (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK 522 and with zero avail_out, it must be called again after making room in the 523 output buffer because there might be more output pending. 524 525 If the parameter flush is set to Z_SYNC_FLUSH, all pending output is 526 flushed to the output buffer and the output is aligned on a byte boundary, so 527 that the decompressor can get all input data available so far. (In particular 528 avail_in is zero after the call if enough output space has been provided 529 before the call.) Flushing may degrade compression for some compression 530 algorithms and so it should be used only when necessary. 531 532 If flush is set to Z_FULL_FLUSH, all output is flushed as with 533 Z_SYNC_FLUSH, and the compression state is reset so that decompression can 534 restart from this point if previous compressed data has been damaged or if 535 random access is desired. Using Z_FULL_FLUSH too often can seriously degrade 536 the compression. 537 538 If deflate returns with avail_out == 0, this function must be called again 539 with the same value of the flush parameter and more output space (updated 540 avail_out), until the flush is complete (deflate returns with non-zero 541 avail_out). 542 543 If the parameter flush is set to Z_PACKET_FLUSH, the compression 544 block is terminated, and a zero-length stored block is output, 545 omitting the length bytes (the effect of this is that the 3-bit type 546 code 000 for a stored block is output, and the output is then 547 byte-aligned). This is designed for use at the end of a PPP packet. 548 549 550 If the parameter flush is set to Z_FINISH, pending input is processed, 551 pending output is flushed and deflate returns with Z_STREAM_END if there 552 was enough output space; if deflate returns with Z_OK, this function must be 553 called again with Z_FINISH and more output space (updated avail_out) but no 554 more input data, until it returns with Z_STREAM_END or an error. After 555 deflate has returned Z_STREAM_END, the only possible operations on the 556 stream are deflateReset or deflateEnd. 557 558 Z_FINISH can be used immediately after deflateInit if all the compression 559 is to be done in a single step. In this case, avail_out must be at least 560 0.1% larger than avail_in plus 12 bytes. If deflate does not return 561 Z_STREAM_END, then it must be called again as described above. 562 563 deflate() sets strm->adler to the adler32 checksum of all input read 564 so far (that is, total_in bytes). 565 566 deflate() may update data_type if it can make a good guess about 567 the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered 568 binary. This field is only for information purposes and does not affect 569 the compression algorithm in any manner. 570 571 deflate() returns Z_OK if some progress has been made (more input 572 processed or more output produced), Z_STREAM_END if all input has been 573 consumed and all output has been produced (only when flush is set to 574 Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example 575 if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible 576 (for example avail_in or avail_out was zero). 577*/ 578 579 580ZEXTERN int ZEXPORT deflateEnd(z_streamp); 581/* 582 All dynamically allocated data structures for this stream are freed. 583 This function discards any unprocessed input and does not flush any 584 pending output. 585 586 deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the 587 stream state was inconsistent, Z_DATA_ERROR if the stream was freed 588 prematurely (some input or output was discarded). In the error case, 589 msg may be set but then points to a static string (which must not be 590 deallocated). 591*/ 592 593 594/* 595ZEXTERN int ZEXPORT inflateInit(z_streamp); 596 597 Initializes the internal stream state for decompression. The fields 598 next_in, avail_in, zalloc, zfree and opaque must be initialized before by 599 the caller. If next_in is not Z_NULL and avail_in is large enough (the exact 600 value depends on the compression method), inflateInit determines the 601 compression method from the zlib header and allocates all data structures 602 accordingly; otherwise the allocation will be deferred to the first call of 603 inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to 604 use default allocation functions. 605 606 inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough 607 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the 608 version assumed by the caller. msg is set to null if there is no error 609 message. inflateInit does not perform any decompression apart from reading 610 the zlib header if present: this will be done by inflate(). (So next_in and 611 avail_in may be modified, but next_out and avail_out are unchanged.) 612*/ 613 614 615ZEXTERN int ZEXPORT inflate(z_streamp, int); 616/* 617 inflate decompresses as much data as possible, and stops when the input 618 buffer becomes empty or the output buffer becomes full. It may some 619 introduce some output latency (reading input without producing any output) 620 except when forced to flush. 621 622 The detailed semantics are as follows. inflate performs one or both of the 623 following actions: 624 625 - Decompress more input starting at next_in and update next_in and avail_in 626 accordingly. If not all input can be processed (because there is not 627 enough room in the output buffer), next_in is updated and processing 628 will resume at this point for the next call of inflate(). 629 630 - Provide more output starting at next_out and update next_out and avail_out 631 accordingly. inflate() provides as much output as possible, until there 632 is no more input data or no more space in the output buffer (see below 633 about the flush parameter). 634 635 Before the call of inflate(), the application should ensure that at least 636 one of the actions is possible, by providing more input and/or consuming 637 more output, and updating the next_* and avail_* values accordingly. 638 The application can consume the uncompressed output when it wants, for 639 example when the output buffer is full (avail_out == 0), or after each 640 call of inflate(). If inflate returns Z_OK and with zero avail_out, it 641 must be called again after making room in the output buffer because there 642 might be more output pending. 643 644 If the parameter flush is set to Z_SYNC_FLUSH or Z_PACKET_FLUSH, 645 inflate flushes as much output as possible to the output buffer. The 646 flushing behavior of inflate is not specified for values of the flush 647 parameter other than Z_SYNC_FLUSH, Z_PACKET_FLUSH or Z_FINISH, but the 648 current implementation actually flushes as much output as possible 649 anyway. For Z_PACKET_FLUSH, inflate checks that once all the input data 650 has been consumed, it is expecting to see the length field of a stored 651 block; if not, it returns Z_DATA_ERROR. 652 653 inflate() should normally be called until it returns Z_STREAM_END or an 654 error. However if all decompression is to be performed in a single step 655 (a single call of inflate), the parameter flush should be set to 656 Z_FINISH. In this case all pending input is processed and all pending 657 output is flushed; avail_out must be large enough to hold all the 658 uncompressed data. (The size of the uncompressed data may have been saved 659 by the compressor for this purpose.) The next operation on this stream must 660 be inflateEnd to deallocate the decompression state. The use of Z_FINISH 661 is never required, but can be used to inform inflate that a faster routine 662 may be used for the single inflate() call. 663 664 If a preset dictionary is needed at this point (see inflateSetDictionary 665 below), inflate sets strm-adler to the adler32 checksum of the 666 dictionary chosen by the compressor and returns Z_NEED_DICT; otherwise 667 it sets strm->adler to the adler32 checksum of all output produced 668 so far (that is, total_out bytes) and returns Z_OK, Z_STREAM_END or 669 an error code as described below. At the end of the stream, inflate() 670 checks that its computed adler32 checksum is equal to that saved by the 671 compressor and returns Z_STREAM_END only if the checksum is correct. 672 673 inflate() returns Z_OK if some progress has been made (more input processed 674 or more output produced), Z_STREAM_END if the end of the compressed data has 675 been reached and all uncompressed output has been produced, Z_NEED_DICT if a 676 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was 677 corrupted (input stream not conforming to the zlib format or incorrect 678 adler32 checksum), Z_STREAM_ERROR if the stream structure was inconsistent 679 (for example if next_in or next_out was NULL), Z_MEM_ERROR if there was not 680 enough memory, Z_BUF_ERROR if no progress is possible or if there was not 681 enough room in the output buffer when Z_FINISH is used. In the Z_DATA_ERROR 682 case, the application may then call inflateSync to look for a good 683 compression block. 684*/ 685 686 687ZEXTERN int ZEXPORT inflateEnd(z_streamp); 688/* 689 All dynamically allocated data structures for this stream are freed. 690 This function discards any unprocessed input and does not flush any 691 pending output. 692 693 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state 694 was inconsistent. In the error case, msg may be set but then points to a 695 static string (which must not be deallocated). 696*/ 697 698 /* Advanced functions */ 699 700/* 701 The following functions are needed only in some special applications. 702*/ 703 704/* 705ZEXTERN int ZEXPORT deflateInit2(z_streamp, int, int, int, int, int); 706 707 This is another version of deflateInit with more compression options. The 708 fields next_in, zalloc, zfree and opaque must be initialized before by 709 the caller. 710 711 The method parameter is the compression method. It must be Z_DEFLATED in 712 this version of the library. 713 714 The windowBits parameter is the base two logarithm of the window size 715 (the size of the history buffer). It should be in the range 8..15 for this 716 version of the library. Larger values of this parameter result in better 717 compression at the expense of memory usage. The default value is 15 if 718 deflateInit is used instead. 719 720 The memLevel parameter specifies how much memory should be allocated 721 for the internal compression state. memLevel=1 uses minimum memory but 722 is slow and reduces compression ratio; memLevel=9 uses maximum memory 723 for optimal speed. The default value is 8. See zconf.h for total memory 724 usage as a function of windowBits and memLevel. 725 726 The strategy parameter is used to tune the compression algorithm. Use the 727 value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a 728 filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no 729 string match). Filtered data consists mostly of small values with a 730 somewhat random distribution. In this case, the compression algorithm is 731 tuned to compress them better. The effect of Z_FILTERED is to force more 732 Huffman coding and less string matching; it is somewhat intermediate 733 between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects 734 the compression ratio but not the correctness of the compressed output even 735 if it is not set appropriately. 736 737 deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 738 memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid 739 method). msg is set to null if there is no error message. deflateInit2 does 740 not perform any compression: this will be done by deflate(). 741*/ 742 743ZEXTERN int ZEXPORT deflateSetDictionary(z_streamp, const Bytef *, uInt); 744/* 745 Initializes the compression dictionary from the given byte sequence 746 without producing any compressed output. This function must be called 747 immediately after deflateInit, deflateInit2 or deflateReset, before any 748 call of deflate. The compressor and decompressor must use exactly the same 749 dictionary (see inflateSetDictionary). 750 751 The dictionary should consist of strings (byte sequences) that are likely 752 to be encountered later in the data to be compressed, with the most commonly 753 used strings preferably put towards the end of the dictionary. Using a 754 dictionary is most useful when the data to be compressed is short and can be 755 predicted with good accuracy; the data can then be compressed better than 756 with the default empty dictionary. 757 758 Depending on the size of the compression data structures selected by 759 deflateInit or deflateInit2, a part of the dictionary may in effect be 760 discarded, for example if the dictionary is larger than the window size in 761 deflate or deflate2. Thus the strings most likely to be useful should be 762 put at the end of the dictionary, not at the front. 763 764 Upon return of this function, strm->adler is set to the Adler32 value 765 of the dictionary; the decompressor may later use this value to determine 766 which dictionary has been used by the compressor. (The Adler32 value 767 applies to the whole dictionary even if only a subset of the dictionary is 768 actually used by the compressor.) 769 770 deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a 771 parameter is invalid (such as NULL dictionary) or the stream state is 772 inconsistent (for example if deflate has already been called for this stream 773 or if the compression method is bsort). deflateSetDictionary does not 774 perform any compression: this will be done by deflate(). 775*/ 776 777ZEXTERN int ZEXPORT deflateCopy(z_streamp, z_streamp); 778/* 779 Sets the destination stream as a complete copy of the source stream. 780 781 This function can be useful when several compression strategies will be 782 tried, for example when there are several ways of pre-processing the input 783 data with a filter. The streams that will be discarded should then be freed 784 by calling deflateEnd. Note that deflateCopy duplicates the internal 785 compression state which can be quite large, so this strategy is slow and 786 can consume lots of memory. 787 788 deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not 789 enough memory, Z_STREAM_ERROR if the source stream state was inconsistent 790 (such as zalloc being NULL). msg is left unchanged in both source and 791 destination. 792*/ 793 794extern int inflateIncomp(z_stream *); 795/* 796 This function adds the data at next_in (avail_in bytes) to the output 797 history without performing any output. There must be no pending output, 798 and the decompressor must be expecting to see the start of a block. 799 Calling this function is equivalent to decompressing a stored block 800 containing the data at next_in (except that the data is not output). 801*/ 802 803ZEXTERN int ZEXPORT deflateReset(z_streamp); 804/* 805 This function is equivalent to deflateEnd followed by deflateInit, 806 but does not free and reallocate all the internal compression state. 807 The stream will keep the same compression level and any other attributes 808 that may have been set by deflateInit2. 809 810 deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 811 stream state was inconsistent (such as zalloc or state being NULL). 812*/ 813 814ZEXTERN int ZEXPORT deflateParams(z_streamp, int, int); 815/* 816 Dynamically update the compression level and compression strategy. The 817 interpretation of level and strategy is as in deflateInit2. This can be 818 used to switch between compression and straight copy of the input data, or 819 to switch to a different kind of input data requiring a different 820 strategy. If the compression level is changed, the input available so far 821 is compressed with the old level (and may be flushed); the new level will 822 take effect only at the next call of deflate(). 823 824 Before the call of deflateParams, the stream state must be set as for 825 a call of deflate(), since the currently available input may have to 826 be compressed and flushed. In particular, strm->avail_out must be non-zero. 827 828 deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source 829 stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR 830 if strm->avail_out was zero. 831*/ 832 833ZEXTERN int ZEXPORT deflateOutputPending(z_streamp); 834/* 835 Returns the number of bytes of output which are immediately 836 available from the compressor (i.e. without any further input 837 or flush). 838*/ 839 840/* 841ZEXTERN int ZEXPORT inflateInit2(z_streamp, int); 842 843 This is another version of inflateInit with an extra parameter. The 844 fields next_in, avail_in, zalloc, zfree and opaque must be initialized 845 before by the caller. 846 847 The windowBits parameter is the base two logarithm of the maximum window 848 size (the size of the history buffer). It should be in the range 8..15 for 849 this version of the library. The default value is 15 if inflateInit is used 850 instead. If a compressed stream with a larger window size is given as 851 input, inflate() will return with the error code Z_DATA_ERROR instead of 852 trying to allocate a larger window. 853 854 inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 855 memory, Z_STREAM_ERROR if a parameter is invalid (such as a negative 856 memLevel). msg is set to null if there is no error message. inflateInit2 857 does not perform any decompression apart from reading the zlib header if 858 present: this will be done by inflate(). (So next_in and avail_in may be 859 modified, but next_out and avail_out are unchanged.) 860*/ 861 862ZEXTERN int ZEXPORT inflateSetDictionary(z_streamp, const Bytef *, uInt); 863/* 864 Initializes the decompression dictionary from the given uncompressed byte 865 sequence. This function must be called immediately after a call of inflate 866 if this call returned Z_NEED_DICT. The dictionary chosen by the compressor 867 can be determined from the Adler32 value returned by this call of 868 inflate. The compressor and decompressor must use exactly the same 869 dictionary (see deflateSetDictionary). 870 871 inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a 872 parameter is invalid (such as NULL dictionary) or the stream state is 873 inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the 874 expected one (incorrect Adler32 value). inflateSetDictionary does not 875 perform any decompression: this will be done by subsequent calls of 876 inflate(). 877*/ 878 879ZEXTERN int ZEXPORT inflateSync(z_streamp); 880/* 881 Skips invalid compressed data until a full flush point (see above the 882 description of deflate with Z_FULL_FLUSH) can be found, or until all 883 available input is skipped. No output is provided. 884 885 inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR 886 if no more input was provided, Z_DATA_ERROR if no flush point has been found, 887 or Z_STREAM_ERROR if the stream structure was inconsistent. In the success 888 case, the application may save the current current value of total_in which 889 indicates where valid compressed data was found. In the error case, the 890 application may repeatedly call inflateSync, providing more input each time, 891 until success or end of the input data. 892*/ 893 894ZEXTERN int ZEXPORT inflateReset(z_streamp); 895/* 896 This function is equivalent to inflateEnd followed by inflateInit, 897 but does not free and reallocate all the internal decompression state. 898 The stream will keep attributes that may have been set by inflateInit2. 899 900 inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source 901 stream state was inconsistent (such as zalloc or state being NULL). 902*/ 903 904 905 /* utility functions */ 906 907/* 908 The following utility functions are implemented on top of the 909 basic stream-oriented functions. To simplify the interface, some 910 default options are assumed (compression level and memory usage, 911 standard memory allocation functions). The source code of these 912 utility functions can easily be modified if you need special options. 913*/ 914 915ZEXTERN int ZEXPORT compress(Bytef *, uLongf *, const Bytef *, uLong); 916/* 917 Compresses the source buffer into the destination buffer. sourceLen is 918 the byte length of the source buffer. Upon entry, destLen is the total 919 size of the destination buffer, which must be at least 0.1% larger than 920 sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the 921 compressed buffer. 922 This function can be used to compress a whole file at once if the 923 input file is mmap'ed. 924 compress returns Z_OK if success, Z_MEM_ERROR if there was not 925 enough memory, Z_BUF_ERROR if there was not enough room in the output 926 buffer. 927*/ 928 929ZEXTERN int ZEXPORT compress2(Bytef *, uLongf *, const Bytef *, 930 uLong, int); 931/* 932 Compresses the source buffer into the destination buffer. The level 933 parameter has the same meaning as in deflateInit. sourceLen is the byte 934 length of the source buffer. Upon entry, destLen is the total size of the 935 destination buffer, which must be at least 0.1% larger than sourceLen plus 936 12 bytes. Upon exit, destLen is the actual size of the compressed buffer. 937 938 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough 939 memory, Z_BUF_ERROR if there was not enough room in the output buffer, 940 Z_STREAM_ERROR if the level parameter is invalid. 941*/ 942 943ZEXTERN int ZEXPORT uncompress(Bytef *, uLongf *, const Bytef *, uLong); 944/* 945 Decompresses the source buffer into the destination buffer. sourceLen is 946 the byte length of the source buffer. Upon entry, destLen is the total 947 size of the destination buffer, which must be large enough to hold the 948 entire uncompressed data. (The size of the uncompressed data must have 949 been saved previously by the compressor and transmitted to the decompressor 950 by some mechanism outside the scope of this compression library.) 951 Upon exit, destLen is the actual size of the compressed buffer. 952 This function can be used to decompress a whole file at once if the 953 input file is mmap'ed. 954 955 uncompress returns Z_OK if success, Z_MEM_ERROR if there was not 956 enough memory, Z_BUF_ERROR if there was not enough room in the output 957 buffer, or Z_DATA_ERROR if the input data was corrupted. 958*/ 959 960 961typedef voidp gzFile; 962 963ZEXTERN gzFile ZEXPORT gzopen(const char *, const char *); 964/* 965 Opens a gzip (.gz) file for reading or writing. The mode parameter 966 is as in fopen ("rb" or "wb") but can also include a compression level 967 ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for 968 Huffman only compression as in "wb1h". (See the description 969 of deflateInit2 for more information about the strategy parameter.) 970 971 gzopen can be used to read a file which is not in gzip format; in this 972 case gzread will directly read from the file without decompression. 973 974 gzopen returns NULL if the file could not be opened or if there was 975 insufficient memory to allocate the (de)compression state; errno 976 can be checked to distinguish the two cases (if errno is zero, the 977 zlib error is Z_MEM_ERROR). */ 978 979ZEXTERN gzFile ZEXPORT gzdopen(int, const char *); 980/* 981 gzdopen() associates a gzFile with the file descriptor fd. File 982 descriptors are obtained from calls like open, dup, creat, pipe or 983 fileno (in the file has been previously opened with fopen). 984 The mode parameter is as in gzopen. 985 The next call of gzclose on the returned gzFile will also close the 986 file descriptor fd, just like fclose(fdopen(fd), mode) closes the file 987 descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). 988 gzdopen returns NULL if there was insufficient memory to allocate 989 the (de)compression state. 990*/ 991 992ZEXTERN int ZEXPORT gzsetparams(gzFile, int, int); 993/* 994 Dynamically update the compression level or strategy. See the description 995 of deflateInit2 for the meaning of these parameters. 996 gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not 997 opened for writing. 998*/ 999 1000ZEXTERN int ZEXPORT gzread(gzFile, voidp, unsigned); 1001/* 1002 Reads the given number of uncompressed bytes from the compressed file. 1003 If the input file was not in gzip format, gzread copies the given number 1004 of bytes into the buffer. 1005 gzread returns the number of uncompressed bytes actually read (0 for 1006 end of file, -1 for error). */ 1007 1008ZEXTERN int ZEXPORT gzwrite(gzFile, const voidp, unsigned); 1009/* 1010 Writes the given number of uncompressed bytes into the compressed file. 1011 gzwrite returns the number of uncompressed bytes actually written 1012 (0 in case of error). 1013*/ 1014 1015ZEXTERN int ZEXPORTVA gzprintf(gzFile, const char *, ...) 1016 __attribute__((__format__(__printf__, 2, 3))); 1017/* 1018 Converts, formats, and writes the args to the compressed file under 1019 control of the format string, as in fprintf. gzprintf returns the number of 1020 uncompressed bytes actually written (0 in case of error). 1021*/ 1022 1023ZEXTERN int ZEXPORT gzputs(gzFile, const char *); 1024/* 1025 Writes the given null-terminated string to the compressed file, excluding 1026 the terminating null character. 1027 gzputs returns the number of characters written, or -1 in case of error. 1028*/ 1029 1030ZEXTERN char * ZEXPORT gzgets(gzFile, char *, int); 1031/* 1032 Reads bytes from the compressed file until len-1 characters are read, or 1033 a newline character is read and transferred to buf, or an end-of-file 1034 condition is encountered. The string is then terminated with a null 1035 character. 1036 gzgets returns buf, or Z_NULL in case of error. 1037*/ 1038 1039ZEXTERN int ZEXPORT gzputc(gzFile, int); 1040/* 1041 Writes c, converted to an unsigned char, into the compressed file. 1042 gzputc returns the value that was written, or -1 in case of error. 1043*/ 1044 1045ZEXTERN int ZEXPORT gzgetc(gzFile); 1046/* 1047 Reads one byte from the compressed file. gzgetc returns this byte 1048 or -1 in case of end of file or error. 1049*/ 1050 1051ZEXTERN int ZEXPORT gzflush(gzFile, int); 1052/* 1053 Flushes all pending output into the compressed file. The parameter 1054 flush is as in the deflate() function. The return value is the zlib 1055 error number (see function gzerror below). gzflush returns Z_OK if 1056 the flush parameter is Z_FINISH and all output could be flushed. 1057 gzflush should be called only when strictly necessary because it can 1058 degrade compression. 1059 1060*/ 1061 1062/* 1063 * NetBSD note: 1064 * "long" gzseek has been there till Oct 1999 (1.4L), which was wrong. 1065 */ 1066ZEXTERN z_off_t ZEXPORT gzseek(gzFile, z_off_t, int); 1067/* 1068 Sets the starting position for the next gzread or gzwrite on the 1069 given compressed file. The offset represents a number of bytes in the 1070 uncompressed data stream. The whence parameter is defined as in lseek(2); 1071 the value SEEK_END is not supported. 1072 If the file is opened for reading, this function is emulated but can be 1073 extremely slow. If the file is opened for writing, only forward seeks are 1074 supported; gzseek then compresses a sequence of zeroes up to the new 1075 starting position. 1076 1077 gzseek returns the resulting offset location as measured in bytes from 1078 the beginning of the uncompressed stream, or -1 in case of error, in 1079 particular if the file is opened for writing and the new starting position 1080 would be before the current position. 1081*/ 1082 1083ZEXTERN int ZEXPORT gzrewind(gzFile); 1084/* 1085 Rewinds the given file. This function is supported only for reading. 1086 1087 gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) 1088*/ 1089 1090/* 1091 * NetBSD note: 1092 * "long" gztell has been there till Oct 1999 (1.4L), which was wrong. 1093 */ 1094ZEXTERN z_off_t ZEXPORT gztell(gzFile); 1095/* 1096 Returns the starting position for the next gzread or gzwrite on the 1097 given compressed file. This position represents a number of bytes in the 1098 uncompressed data stream. 1099 1100 gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) 1101*/ 1102 1103ZEXTERN int ZEXPORT gzeof(gzFile); 1104/* 1105 Returns 1 when EOF has previously been detected reading the given 1106 input stream, otherwise zero. 1107*/ 1108 1109ZEXTERN int ZEXPORT gzclose(gzFile); 1110/* 1111 Flushes all pending output if necessary, closes the compressed file 1112 and deallocates all the (de)compression state. The return value is the zlib 1113 error number (see function gzerror below). 1114*/ 1115 1116ZEXTERN const char * ZEXPORT gzerror(gzFile, int *); 1117/* 1118 Returns the error message for the last error which occurred on the 1119 given compressed file. errnum is set to zlib error number. If an 1120 error occurred in the file system and not in the compression library, 1121 errnum is set to Z_ERRNO and the application may consult errno 1122 to get the exact error code. 1123*/ 1124 1125 /* checksum functions */ 1126 1127/* 1128 These functions are not related to compression but are exported 1129 anyway because they might be useful in applications using the 1130 compression library. 1131*/ 1132 1133ZEXTERN uLong ZEXPORT adler32(uLong, const Bytef *, uInt); 1134 1135/* 1136 Update a running Adler-32 checksum with the bytes buf[0..len-1] and 1137 return the updated checksum. If buf is NULL, this function returns 1138 the required initial value for the checksum. 1139 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed 1140 much faster. Usage example: 1141 1142 uLong adler = adler32(0L, Z_NULL, 0); 1143 1144 while (read_buffer(buffer, length) != EOF) { 1145 adler = adler32(adler, buffer, length); 1146 } 1147 if (adler != original_adler) error(); 1148*/ 1149 1150#ifdef STANDALONE 1151ZEXTERN uLong ZEXPORT crc32(uLong, const Bytef *, uInt); 1152#endif 1153/* 1154 Update a running crc with the bytes buf[0..len-1] and return the updated 1155 crc. If buf is NULL, this function returns the required initial value 1156 for the crc. Pre- and post-conditioning (one's complement) is performed 1157 within this function so it shouldn't be done by the application. 1158 Usage example: 1159 1160 uLong crc = crc32(0L, Z_NULL, 0); 1161 1162 while (read_buffer(buffer, length) != EOF) { 1163 crc = crc32(crc, buffer, length); 1164 } 1165 if (crc != original_crc) error(); 1166*/ 1167 1168 1169 /* various hacks, don't look :) */ 1170 1171/* deflateInit and inflateInit are macros to allow checking the zlib version 1172 * and the compiler's view of z_stream: 1173 */ 1174ZEXTERN int ZEXPORT deflateInit_(z_streamp, int, const char *, int); 1175ZEXTERN int ZEXPORT inflateInit_(z_streamp, const char *, int); 1176ZEXTERN int ZEXPORT deflateInit2_(z_streamp, int, int, int, int, 1177 int, const char *, int); 1178ZEXTERN int ZEXPORT inflateInit2_(z_streamp, int, const char *, int); 1179#define deflateInit(strm, level) \ 1180 deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) 1181#define inflateInit(strm) \ 1182 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) 1183#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ 1184 deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ 1185 (strategy), ZLIB_VERSION, sizeof(z_stream)) 1186#define inflateInit2(strm, windowBits) \ 1187 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) 1188 1189 1190#if !defined(Z_UTIL_H) && !defined(NO_DUMMY_DECL) 1191 struct internal_state {int dummy;}; /* hack for buggy compilers */ 1192#endif 1193 1194ZEXTERN const char * ZEXPORT zError(int); 1195ZEXTERN int ZEXPORT inflateSyncPoint(z_streamp); 1196ZEXTERN const uLongf * ZEXPORT get_crc_table(void); 1197 1198#ifdef __cplusplus 1199} 1200#endif 1201#endif /* !ZLIB_H */ 1202 1203#endif /* !_NET_ZLIB_H_ */ 1204/* -- zlib.h */ 1205