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.
9 * ==FILEVERSION 960122==
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.
15 /* zlib.h -- interface of the 'zlib' general purpose compression library
16 version 1.2.3, July 18th, 2005
18 Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
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.
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:
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.
36 Jean-loup Gailly Mark Adler
37 jloup@gzip.org madler@alumni.caltech.edu
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).
52 #define ZLIB_VERSION "1.2.3"
53 #define ZLIB_VERNUM 0x1230
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
61 /* Begin of new zconf.h */
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.
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
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
103 # define uLong z_uLong
104 # define Bytef z_Bytef
105 # define charf z_charf
107 # define uIntf z_uIntf
108 # define uLongf z_uLongf
109 # define voidpf z_voidpf
110 # define voidp z_voidp
113 #if defined(__MSDOS__) && !defined(MSDOS)
116 #if (defined(OS_2) || defined(__OS2__)) && !defined(OS2)
119 #if defined(_WINDOWS) && !defined(WINDOWS)
122 #if defined(_WIN32) || defined(_WIN32_WCE) || defined(__WIN32__)
127 #if (defined(MSDOS) || defined(OS2) || defined(WINDOWS)) && !defined(WIN32)
128 # if !defined(__GNUC__) && !defined(__FLAT__) && !defined(__386__)
136 * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
137 * than 64k bytes at a time (needed on systems with 16-bit int).
143 # define UNALIGNED_OK
146 #ifdef __STDC_VERSION__
150 # if __STDC_VERSION__ >= 199901L
156 #if !defined(STDC) && (defined(__STDC__) || defined(__cplusplus))
159 #if !defined(STDC) && (defined(__GNUC__) || defined(__BORLANDC__))
162 #if !defined(STDC) && (defined(MSDOS) || defined(WINDOWS) || defined(WIN32))
165 #if !defined(STDC) && (defined(OS2) || defined(__HOS_AIX__))
169 #if defined(__OS400__) && !defined(STDC) /* iSeries (formerly AS/400). */
174 # ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */
175 # define const /* note: need a more gentle solution here */
179 /* Some Mac compilers merge all .h files incorrectly: */
180 #if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
181 # define NO_DUMMY_DECL
184 /* Maximum value for memLevel in deflateInit2 */
185 #ifndef MAX_MEM_LEVEL
187 # define MAX_MEM_LEVEL 8
189 # define MAX_MEM_LEVEL 9
193 /* Maximum value for windowBits in deflateInit2 and inflateInit2.
194 * WARNING: reducing MAX_WBITS makes minigzip unable to extract .gz files
195 * created by gzip. (Files created by minigzip can still be extracted by
199 # define MAX_WBITS 15 /* 32K LZ77 window */
202 /* The memory requirements for deflate are (in bytes):
203 (1 << (windowBits+2)) + (1 << (memLevel+9))
204 that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values)
205 plus a few kilobytes for small objects. For example, if you want to reduce
206 the default memory requirements from 256K to 128K, compile with
207 make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
208 Of course this will generally degrade compression (there's no free lunch).
210 The memory requirements for inflate are (in bytes) 1 << windowBits
211 that is, 32K for windowBits=15 (default value) plus a few kilobytes
215 /* Type declarations */
217 #ifndef OF /* function prototypes */
219 # define OF(args) args
225 /* The following definitions for FAR are needed only for MSDOS mixed
226 * model programming (small or medium model with some far allocations).
227 * This was tested only with MSC; for other MSDOS compilers you may have
228 * to define NO_MEMCPY in zutil.h. If you don't need the mixed model,
229 * just define FAR to be empty.
232 # if defined(M_I86SM) || defined(M_I86MM)
233 /* MSC small or medium model */
234 # define SMALL_MEDIUM
241 # if (defined(__SMALL__) || defined(__MEDIUM__))
242 /* Turbo C small or medium model */
243 # define SMALL_MEDIUM
252 #if defined(WINDOWS) || defined(WIN32)
253 /* If building or using zlib as a DLL, define ZLIB_DLL.
254 * This is not mandatory, but it offers a little performance increase.
257 # if defined(WIN32) && (!defined(__BORLANDC__) || (__BORLANDC__ >= 0x500))
258 # ifdef ZLIB_INTERNAL
259 # define ZEXTERN extern __declspec(dllexport)
261 # define ZEXTERN extern __declspec(dllimport)
264 # endif /* ZLIB_DLL */
265 /* If building or using zlib with the WINAPI/WINAPIV calling convention,
266 * define ZLIB_WINAPI.
267 * Caution: the standard ZLIB1.DLL is NOT compiled using ZLIB_WINAPI.
273 # include <windows.h>
274 /* No need for _export, use ZLIB.DEF instead. */
275 /* For complete Windows compatibility, use WINAPI, not __stdcall. */
276 # define ZEXPORT WINAPI
278 # define ZEXPORTVA WINAPIV
280 # define ZEXPORTVA FAR CDECL
285 #if defined (__BEOS__)
287 # ifdef ZLIB_INTERNAL
288 # define ZEXPORT __declspec(dllexport)
289 # define ZEXPORTVA __declspec(dllexport)
291 # define ZEXPORT __declspec(dllimport)
292 # define ZEXPORTVA __declspec(dllimport)
298 # define ZEXTERN extern
311 #if !defined(__MACTYPES__)
312 typedef unsigned char Byte; /* 8 bits */
314 typedef unsigned int uInt; /* 16 bits or more */
315 typedef unsigned long uLong; /* 32 bits or more */
318 /* Borland C/C++ and some old MSC versions ignore FAR inside typedef */
319 # define Bytef Byte FAR
321 typedef Byte FAR Bytef;
323 typedef char FAR charf;
324 typedef int FAR intf;
325 typedef uInt FAR uIntf;
326 typedef uLong FAR uLongf;
329 typedef void const *voidpc;
330 typedef void FAR *voidpf;
333 typedef Byte const *voidpc;
334 typedef Byte FAR *voidpf;
339 # include <unixio.h> /* for off_t */
341 # define z_off_t off_t
343 # define SEEK_SET 0 /* Seek from beginning of file. */
344 # define SEEK_CUR 1 /* Seek from current position. */
345 # define SEEK_END 2 /* Set file pointer to EOF plus "offset" */
348 # define z_off_t long
351 #if defined(__OS400__)
352 # define NO_vsnprintf
356 # define NO_vsnprintf
362 /* MVS linker does not support external names larger than 8 bytes */
364 # pragma map(deflateInit_,"DEIN")
365 # pragma map(deflateInit2_,"DEIN2")
366 # pragma map(deflateEnd,"DEEND")
367 # pragma map(deflateBound,"DEBND")
368 # pragma map(inflateInit_,"ININ")
369 # pragma map(inflateInit2_,"ININ2")
370 # pragma map(inflateEnd,"INEND")
371 # pragma map(inflateSync,"INSY")
372 # pragma map(inflateSetDictionary,"INSEDI")
373 # pragma map(compressBound,"CMBND")
374 # pragma map(inflate_table,"INTABL")
375 # pragma map(inflate_fast,"INFA")
376 # pragma map(inflate_copyright,"INCOPY")
378 /* End of new zconf.h */
381 The 'zlib' compression library provides in-memory compression and
382 decompression functions, including integrity checks of the uncompressed
383 data. This version of the library supports only one compression method
384 (deflation) but other algorithms will be added later and will have the same
387 Compression can be done in a single step if the buffers are large
388 enough (for example if an input file is mmap'ed), or can be done by
389 repeated calls of the compression function. In the latter case, the
390 application must provide more input and/or consume the output
391 (providing more output space) before each call.
393 The compressed data format used by default by the in-memory functions is
394 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
395 around a deflate stream, which is itself documented in RFC 1951.
397 The library also supports reading and writing files in gzip (.gz) format
398 with an interface similar to that of stdio using the functions that start
399 with "gz". The gzip format is different from the zlib format. gzip is a
400 gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
402 This library can optionally read and write gzip streams in memory as well.
404 The zlib format was designed to be compact and fast for use in memory
405 and on communications channels. The gzip format was designed for single-
406 file compression on file systems, has a larger header than zlib to maintain
407 directory information, and uses a different, slower check method than zlib.
409 The library does not install any signal handler. The decoder checks
410 the consistency of the compressed data, so the library should never
411 crash even in case of corrupted input.
414 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
415 typedef void (*free_func) OF((voidpf opaque, voidpf address, uInt size));
416 typedef void (*cb_func) OF((Bytef *buf, uInt len));
418 struct internal_state;
420 typedef struct z_stream_s {
421 Bytef *next_in; /* next input byte */
422 uInt avail_in; /* number of bytes available at next_in */
423 uLong total_in; /* total nb of input bytes read so far */
424 Bytef *next_out; /* next output byte should be put there */
425 uInt avail_out; /* remaining free space at next_out */
426 uLong total_out; /* total nb of bytes output so far */
427 char *msg; /* last error message, NULL if no error */
428 struct internal_state FAR *state; /* not visible by applications */
429 alloc_func zalloc; /* used to allocate the internal state */
430 free_func zfree; /* used to free the internal state */
431 voidpf opaque; /* private data object passed to zalloc and zfree */
432 int data_type; /* best guess about the data type:
434 cb_func outcb; /* called regularly just before blocks of output */
435 uLong adler; /* adler32 value of the uncompressed data */
436 uLong reserved; /* reserved for future use */
439 typedef z_stream FAR *z_streamp;
442 gzip header information passed to and from zlib routines. See RFC 1952
443 for more details on the meanings of these fields.
445 typedef struct gz_header_s {
446 int text; /* true if compressed data believed to be text */
447 uLong time; /* modification time */
448 int xflags; /* extra flags (not used when writing a gzip file) */
449 int os; /* operating system */
450 Bytef *extra; /* pointer to extra field or Z_NULL if none */
451 uInt extra_len; /* extra field length (valid if extra != Z_NULL) */
452 uInt extra_max; /* space at extra (only when reading header) */
453 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
454 uInt name_max; /* space at name (only when reading header) */
455 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
456 uInt comm_max; /* space at comment (only when reading header) */
457 int hcrc; /* true if there was or will be a header crc */
458 int done; /* true when done reading gzip header (not used
459 when writing a gzip file) */
462 typedef gz_header FAR *gz_headerp;
466 #define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
467 #define Z_SYNC_FLUSH 2
468 #define Z_FULL_FLUSH 3
471 /* Allowed flush values; see deflate() and inflate() below for details */
474 #define Z_STREAM_END 1
475 #define Z_NEED_DICT 2
477 #define Z_STREAM_ERROR (-2)
478 #define Z_DATA_ERROR (-3)
479 #define Z_MEM_ERROR (-4)
480 #define Z_BUF_ERROR (-5)
481 #define Z_VERSION_ERROR (-6)
482 /* Return codes for the compression/decompression functions. Negative
483 * values are errors, positive values are used for special but normal events.
486 #define Z_NO_COMPRESSION 0
487 #define Z_BEST_SPEED 1
488 #define Z_BEST_COMPRESSION 9
489 #define Z_DEFAULT_COMPRESSION (-1)
490 /* compression levels */
493 #define Z_HUFFMAN_ONLY 2
496 #define Z_DEFAULT_STRATEGY 0
497 /* compression strategy; see deflateInit2() below for details */
501 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
503 /* Possible values of the data_type field (though see inflate()) */
506 /* The deflate compression method (the only one supported in this version) */
508 #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
510 /* basic functions */
512 /* The application can compare zlibVersion and ZLIB_VERSION for consistency.
513 If the first character differs, the library code actually used is
514 not compatible with the zlib.h header file used by the application.
515 This check is automatically made by deflateInit and inflateInit.
518 ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, const char *version,
521 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
523 inflate decompresses as much data as possible, and stops when the input
524 buffer becomes empty or the output buffer becomes full. It may introduce
525 some output latency (reading input without producing any output) except when
528 The detailed semantics are as follows. inflate performs one or both of the
531 - Decompress more input starting at next_in and update next_in and avail_in
532 accordingly. If not all input can be processed (because there is not
533 enough room in the output buffer), next_in is updated and processing
534 will resume at this point for the next call of inflate().
536 - Provide more output starting at next_out and update next_out and avail_out
537 accordingly. inflate() provides as much output as possible, until there
538 is no more input data or no more space in the output buffer (see below
539 about the flush parameter).
541 Before the call of inflate(), the application should ensure that at least
542 one of the actions is possible, by providing more input and/or consuming
543 more output, and updating the next_* and avail_* values accordingly.
544 The application can consume the uncompressed output when it wants, for
545 example when the output buffer is full (avail_out == 0), or after each
546 call of inflate(). If inflate returns Z_OK and with zero avail_out, it
547 must be called again after making room in the output buffer because there
548 might be more output pending.
550 The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
551 Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
552 output as possible to the output buffer. Z_BLOCK requests that inflate() stop
553 if and when it gets to the next deflate block boundary. When decoding the
554 zlib or gzip format, this will cause inflate() to return immediately after
555 the header and before the first block. When doing a raw inflate, inflate()
556 will go ahead and process the first block, and will return when it gets to
557 the end of that block, or when it runs out of data.
559 The Z_BLOCK option assists in appending to or combining deflate streams.
560 Also to assist in this, on return inflate() will set strm->data_type to the
561 number of unused bits in the last byte taken from strm->next_in, plus 64
562 if inflate() is currently decoding the last block in the deflate stream,
563 plus 128 if inflate() returned immediately after decoding an end-of-block
564 code or decoding the complete header up to just before the first byte of the
565 deflate stream. The end-of-block will not be indicated until all of the
566 uncompressed data from that block has been written to strm->next_out. The
567 number of unused bits may in general be greater than seven, except when
568 bit 7 of data_type is set, in which case the number of unused bits will be
571 inflate() should normally be called until it returns Z_STREAM_END or an
572 error. However if all decompression is to be performed in a single step
573 (a single call of inflate), the parameter flush should be set to
574 Z_FINISH. In this case all pending input is processed and all pending
575 output is flushed; avail_out must be large enough to hold all the
576 uncompressed data. (The size of the uncompressed data may have been saved
577 by the compressor for this purpose.) The next operation on this stream must
578 be inflateEnd to deallocate the decompression state. The use of Z_FINISH
579 is never required, but can be used to inform inflate that a faster approach
580 may be used for the single inflate() call.
582 In this implementation, inflate() always flushes as much output as
583 possible to the output buffer, and always uses the faster approach on the
584 first call. So the only effect of the flush parameter in this implementation
585 is on the return value of inflate(), as noted below, or when it returns early
586 because Z_BLOCK is used.
588 If a preset dictionary is needed after this call (see inflateSetDictionary
589 below), inflate sets strm->adler to the adler32 checksum of the dictionary
590 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
591 strm->adler to the adler32 checksum of all output produced so far (that is,
592 total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
593 below. At the end of the stream, inflate() checks that its computed adler32
594 checksum is equal to that saved by the compressor and returns Z_STREAM_END
595 only if the checksum is correct.
597 inflate() will decompress and check either zlib-wrapped or gzip-wrapped
598 deflate data. The header type is detected automatically. Any information
599 contained in the gzip header is not retained, so applications that need that
600 information should instead use raw inflate, see inflateInit2() below, or
601 inflateBack() and perform their own processing of the gzip header and
604 inflate() returns Z_OK if some progress has been made (more input processed
605 or more output produced), Z_STREAM_END if the end of the compressed data has
606 been reached and all uncompressed output has been produced, Z_NEED_DICT if a
607 preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
608 corrupted (input stream not conforming to the zlib format or incorrect check
609 value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
610 if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
611 Z_BUF_ERROR if no progress is possible or if there was not enough room in the
612 output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
613 inflate() can be called again with more input and more output space to
614 continue decompressing. If Z_DATA_ERROR is returned, the application may then
615 call inflateSync() to look for a good compression block if a partial recovery
616 of the data is desired.
619 ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
621 All dynamically allocated data structures for this stream are freed.
622 This function discards any unprocessed input and does not flush any
625 inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
626 was inconsistent. In the error case, msg may be set but then points to a
627 static string (which must not be deallocated).
630 /* Advanced functions */
632 ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
634 /* utility functions */
637 The following utility functions are implemented on top of the
638 basic stream-oriented functions. To simplify the interface, some
639 default options are assumed (compression level and memory usage,
640 standard memory allocation functions). The source code of these
641 utility functions can easily be modified if you need special options.
644 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
646 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
647 return the updated checksum. If buf is NULL, this function returns
648 the required initial value for the checksum.
649 An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
650 much faster. Usage example:
652 uLong adler = adler32(0L, Z_NULL, 0);
654 while (read_buffer(buffer, length) != EOF) {
655 adler = adler32(adler, buffer, length);
657 if (adler != original_adler) error();
661 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
662 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
663 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
664 seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
667 ZEXTERN uInt ZEXPORT crc32 OF((uInt crc, const Bytef *buf, uInt len));
669 Update a running CRC-32 with the bytes buf[0..len-1] and return the
670 updated CRC-32. If buf is NULL, this function returns the required initial
671 value for the for the crc. Pre- and post-conditioning (one's complement) is
672 performed within this function so it shouldn't be done by the application.
675 uLong crc = crc32(0L, Z_NULL, 0);
677 while (read_buffer(buffer, length) != EOF) {
678 crc = crc32(crc, buffer, length);
680 if (crc != original_crc) error();
683 ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
684 const char *version, int stream_size));
685 #define inflateInit(strm) \
686 inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
687 #define inflateInit2(strm, windowBits) \
688 inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
690 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
691 struct internal_state {int dummy;}; /* hack for buggy compilers */