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zlib 0.71

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pull/2/head v0.71
Mark Adler 13 years ago
commit bcf78a2097
28 changed files with 6146 additions and 0 deletions
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  1. 51
      ChangeLog
  2. 59
      Makefile
  3. 57
      README
  4. 46
      adler32.c
  5. 55
      compress.c
  6. 103
      crc32.c
  7. 932
      deflate.c
  8. 270
      deflate.h
  9. 201
      example.c
  10. 459
      gzio.c
  11. 324
      infblock.c
  12. 26
      infblock.h
  13. 217
      infcodes.c
  14. 25
      infcodes.h
  15. 221
      inflate.c
  16. 22
      inflate.h
  17. 67
      inftest.c
  18. 471
      inftrees.c
  19. 62
      inftrees.h
  20. 76
      infutil.c
  21. 86
      infutil.h
  22. 210
      minigzip.c
  23. 1048
      trees.c
  24. 58
      uncompr.c
  25. 66
      zconf.h
  26. 604
      zlib.h
  27. 164
      zutil.c
  28. 166
      zutil.h

51
ChangeLog
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ChangeLog file for zlib
Changes in 0.71 (14 April 95)
- Fixed more MSDOS compilation problems :( There is still a bug with
TurboC large model.
Changes in 0.7 (14 April 95)
- Added full inflate support.
- Simplified the crc32() interface. The pre- and post-conditioning
(one's complement) is now done inside crc32(). WARNING: this is
incompatible with previous versions; see zlib.h for the new usage.
Changes in 0.61 (12 April 95)
- workaround for a bug in TurboC. example and minigzip now work on MSDOS.
Changes in 0.6 (11 April 95)
- added minigzip.c
- added gzdopen to reopen a file descriptor as gzFile
- added transparent reading of non-gziped files in gzread.
- fixed bug in gzread (don't read crc as data)
- fixed bug in destroy (gzio.c) (don't return Z_STREAM_END for gzclose).
- don't allocate big arrays in the stack (for MSDOS)
- fix some MSDOS compilation problems
Changes in 0.5:
- do real compression in deflate.c. Z_PARTIAL_FLUSH is supported but
not yet Z_FULL_FLUSH.
- support decompression but only in a single step (forced Z_FINISH)
- added opaque object for zalloc and zfree.
- added deflateReset and inflateReset
- added a variable zlib_version for consistency checking.
- renamed the 'filter' parameter of deflateInit2 as 'strategy'.
Added Z_FILTERED and Z_HUFFMAN_ONLY constants.
Changes in 0.4:
- avoid "zip" everywhere, use zlib instead of ziplib.
- suppress Z_BLOCK_FLUSH, interpret Z_PARTIAL_FLUSH as block flush
if compression method == 8.
- added adler32 and crc32
- renamed deflateOptions as deflateInit2, call one or the other but not both
- added the method parameter for deflateInit2.
- added inflateInit2
- simplied considerably deflateInit and inflateInit by not supporting
user-provided history buffer. This is supported only in deflateInit2
and inflateInit2.
Changes in 0.3:
- prefix all macro names with Z_
- use Z_FINISH instead of deflateEnd to finish compression.
- added Z_HUFFMAN_ONLY
- added gzerror()

59
Makefile
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CC=cc
CFLAGS=-O
#CFLAGS=-g -DDEBUG
LDFLAGS=-L. -lgz
RANLIB=ranlib
OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
zutil.o inflate.o infblock.o inftrees.o infcodes.o infutil.o
TEST_OBJS = example.o minigzip.o inftest.o
all: example minigzip inftest
test: all
./example
echo hello world | ./minigzip | ./minigzip -d
libgz.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
example: example.o libgz.a
$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
minigzip: minigzip.o libgz.a
$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
inftest: inftest.o libgz.a
$(CC) $(CFLAGS) -o $@ inftest.o $(LDFLAGS)
clean:
rm -f *.o example minigzip inftest libgz.a foo.gz
zip:
zip -ul9 zlib README ChangeLog Makefile *.[ch]
tgz:
cd ..; tar cfz zlib/zlib.tgz zlib/README zlib/ChangeLog zlib/Makefile \
zlib/*.[ch]
# DO NOT DELETE THIS LINE -- make depend depends on it.
adler32.o: zutil.h zlib.h zconf.h
compress.o: zlib.h zconf.h
crc32.o: zutil.h zlib.h zconf.h
deflate.o: deflate.h zutil.h zlib.h zconf.h
example.o: zlib.h zconf.h
gzio.o: zutil.h zlib.h zconf.h
infblock.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
infcodes.o: zutil.h zlib.h zconf.h inftrees.h infutil.h infcodes.h
inflate.o: zutil.h zlib.h zconf.h infblock.h
inftest.o: zutil.h zlib.h zconf.h
inftrees.o: zutil.h zlib.h zconf.h inftrees.h
infutil.o: zutil.h zlib.h zconf.h inftrees.h infutil.h
minigzip.o: zlib.h zconf.h
trees.o: deflate.h zutil.h zlib.h zconf.h
uncompr.o: zlib.h zconf.h
zutil.o: zutil.h zlib.h zconf.h

57
README
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zlib 0.71 is a beta version of a general purpose compression library.
The data format used by the zlib library is described in the
file zlib-3.1.doc, deflate-1.1.doc and gzip-4.1.doc, available
in ftp.uu.net:/pub/archiving/zip/doc.
All functions of the compression library are documented in the file
zlib.h. A usage example of the library is given in the file example.c
which also tests that the library is working correctly.
To compile all files and run the test program, just type: make test
The changes made in version 0.71 are documented in the file ChangeLog.
The main changes since 0.5 are:
- added full inflate support
- added minigzip.c
- added gzdopen to reopen a file descriptor as gzFile
- added transparent reading of non-gziped files in gzread.
- fix some MSDOS problems. example and minigzip now work on MSDOS.
- Simplified the crc32() interface. The pre- and post-conditioning
(one's complement) is now done inside crc32(). WARNING: this is
incompatible with previous versions; see zlib.h for the new usage.
On MSDOS, this version works in large and small model with MSC; in
small model only with TurboC (bug being investigated). For both
compilers, small model compression works only for small values of
MEM_LEVEL and WBITS (see zutil.h), and requires -DUSE_CALLOC.
Copyright (C) 1995 Jean-loup Gailly and Mark Adler
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
Jean-loup Gailly Mark Adler
gzip@prep.ai.mit.edu madler@cco.caltech.edu
If you use the zlib library in a product, we would appreciate *not*
receiving lengthy legal documents to sign. The sources are provided
for free but without warranty of any kind. The library has been
entirely written by Jean-loup Gailly and Mark Adler; it does not
include third-party code.
If you redistribute modified sources, we would appreciate that you include
in the file ChangeLog history information documenting your changes.

46
adler32.c
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/* adler32.c -- compute the Adler-32 checksum of a data stream
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: adler32.c,v 1.5 1995/04/14 14:49:51 jloup Exp $ */
#include "zutil.h"
#define BASE 65521 /* largest prime smaller than 65536 */
#define NMAX 5552
/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
#define DO1(buf) {s1 += *buf++; s2 += s1;}
#define DO2(buf) DO1(buf); DO1(buf);
#define DO4(buf) DO2(buf); DO2(buf);
#define DO8(buf) DO4(buf); DO4(buf);
#define DO16(buf) DO8(buf); DO8(buf);
/* ========================================================================= */
uLong adler32(adler, buf, len)
uLong adler;
Byte *buf;
uInt len;
{
unsigned long s1 = adler & 0xffff;
unsigned long s2 = (adler >> 16) & 0xffff;
int k;
if (buf == Z_NULL) return 1L;
while (len > 0) {
k = len < NMAX ? len : NMAX;
len -= k;
while (k >= 16) {
DO16(buf);
k -= 16;
}
if (k != 0) do {
DO1(buf);
} while (--k);
s1 %= BASE;
s2 %= BASE;
}
return (s2 << 16) | s1;
}

55
compress.c
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/* compress.c -- compress a memory buffer
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: compress.c,v 1.4 1995/04/10 15:52:04 jloup Exp $ */
#include "zlib.h"
/* ===========================================================================
Compresses the source buffer into the destination buffer. sourceLen is
the byte length of the source buffer. Upon entry, destLen is the total
size of the destination buffer, which must be at least 0.1% larger than
sourceLen plus 8 bytes. Upon exit, destLen is the actual size of the
compressed buffer.
This function can be used to compress a whole file at once if the
input file is mmap'ed.
compress returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_BUF_ERROR if there was not enough room in the output
buffer.
*/
int compress (dest, destLen, source, sourceLen)
Byte *dest;
uLong *destLen;
Byte *source;
uLong sourceLen;
{
z_stream stream;
int err;
stream.next_in = source;
stream.avail_in = (uInt)sourceLen;
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
stream.next_out = dest;
stream.avail_out = (uInt)*destLen;
if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
stream.zalloc = (alloc_func)0;
stream.zfree = (free_func)0;
err = deflateInit(&stream, Z_DEFAULT_COMPRESSION);
if (err != Z_OK) return err;
err = deflate(&stream, Z_FINISH);
if (err != Z_OK) {
deflateEnd(&stream);
return err;
}
*destLen = stream.total_out;
err = deflateEnd(&stream);
return err;
}

103
crc32.c
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/* crc32.c -- compute the CRC-32 of a data stream
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: crc32.c,v 1.4 1995/04/14 14:55:12 jloup Exp $ */
#include "zlib.h"
extern uLong crc_table[]; /* crc table, defined below */
/* ========================================================================= */
uLong crc32(crc, buf, len)
uLong crc;
Byte *buf;
uInt len;
{
if (buf == Z_NULL) return 0L;
crc = crc ^ 0xffffffffL;
if (len) do {
crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
} while (--len);
return crc ^ 0xffffffffL;
}
/* =========================================================================
* Make the crc table. This function is needed only if you want to compute
* the table dynamically.
*/
#ifdef DYNAMIC_CRC_TABLE
void make_crc_table()
{
uLong c;
int n, k;
for (n = 0; n &lt; 256; n++)
{
c = (uLong)n;
for (k = 0; k &lt; 8; k++)
c = c & 1 ? 0xedb88320L ^ (c >> 1) : c >> 1;
crc_table[n] = c;
}
}
#endif
/* ========================================================================
* Table of CRC-32's of all single-byte values (made by make_crc_table)
*/
uLong crc_table[] = {
0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
0x2d02ef8dL
};

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deflate.c
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/* deflate.c -- compress data using the deflation algorithm
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/*
* ALGORITHM
*
* The "deflation" process depends on being able to identify portions
* of the input text which are identical to earlier input (within a
* sliding window trailing behind the input currently being processed).
*
* The most straightforward technique turns out to be the fastest for
* most input files: try all possible matches and select the longest.
* The key feature of this algorithm is that insertions into the string
* dictionary are very simple and thus fast, and deletions are avoided
* completely. Insertions are performed at each input character, whereas
* string matches are performed only when the previous match ends. So it
* is preferable to spend more time in matches to allow very fast string
* insertions and avoid deletions. The matching algorithm for small
* strings is inspired from that of Rabin & Karp. A brute force approach
* is used to find longer strings when a small match has been found.
* A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
* (by Leonid Broukhis).
* A previous version of this file used a more sophisticated algorithm
* (by Fiala and Greene) which is guaranteed to run in linear amortized
* time, but has a larger average cost, uses more memory and is patented.
* However the F&G algorithm may be faster for some highly redundant
* files if the parameter max_chain_length (described below) is too large.
*
* ACKNOWLEDGEMENTS
*
* The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
* I found it in 'freeze' written by Leonid Broukhis.
* Thanks to many people for bug reports and testing.
*
* REFERENCES
*
* Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
* Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
*
* A description of the Rabin and Karp algorithm is given in the book
* "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
*
* Fiala,E.R., and Greene,D.H.
* Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
*
*/
/* $Id: deflate.c,v 1.3 1995/04/10 16:03:45 jloup Exp $ */
#include "deflate.h"
char copyright[] = " deflate Copyright 1995 Jean-loup Gailly ";
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
include such an acknowledgment, I would appreciate that you keep this
copyright string in the executable of your product.
*/
#define NIL 0
/* Tail of hash chains */
#ifndef TOO_FAR
# define TOO_FAR 4096
#endif
/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
/* Minimum amount of lookahead, except at the end of the input file.
* See deflate.c for comments about the MIN_MATCH+1.
*/
/* Values for max_lazy_match, good_match and max_chain_length, depending on
* the desired pack level (0..9). The values given below have been tuned to
* exclude worst case performance for pathological files. Better values may be
* found for specific files.
*/
typedef struct config_s {
ush good_length; /* reduce lazy search above this match length */
ush max_lazy; /* do not perform lazy search above this match length */
ush nice_length; /* quit search above this match length */
ush max_chain;
} config;
local config configuration_table[10] = {
/* good lazy nice chain */
/* 0 */ {0, 0, 0, 0}, /* store only */
/* 1 */ {4, 4, 8, 4}, /* maximum speed, no lazy matches */
/* 2 */ {4, 5, 16, 8},
/* 3 */ {4, 6, 32, 32},
/* 4 */ {4, 4, 16, 16}, /* lazy matches */
/* 5 */ {8, 16, 32, 32},
/* 6 */ {8, 16, 128, 128},
/* 7 */ {8, 32, 128, 256},
/* 8 */ {32, 128, 258, 1024},
/* 9 */ {32, 258, 258, 4096}}; /* maximum compression */
/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
* For deflate_fast() (levels <= 3) good is ignored and lazy has a different
* meaning.
*/
#define EQUAL 0
/* result of memcmp for equal strings */
struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
/* ===========================================================================
* Prototypes for local functions.
*/
local void fill_window __P((deflate_state *s));
local int deflate_fast __P((deflate_state *s, int flush));
local int deflate_slow __P((deflate_state *s, int flush));
local void lm_init __P((deflate_state *s));
local int longest_match __P((deflate_state *s, IPos cur_match));
#ifdef ASMV
void match_init __P((void)); /* asm code initialization */
#endif
#ifdef DEBUG
local void check_match __P((deflate_state *s, IPos start, IPos match,
int length));
#endif
/* ===========================================================================
* Update a hash value with the given input byte
* IN assertion: all calls to to UPDATE_HASH are made with consecutive
* input characters, so that a running hash key can be computed from the
* previous key instead of complete recalculation each time.
*/
#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
/* ===========================================================================
* Insert string str in the dictionary and set match_head to the previous head
* of the hash chain (the most recent string with same hash key). Return
* the previous length of the hash chain.
* IN assertion: all calls to to INSERT_STRING are made with consecutive
* input characters and the first MIN_MATCH bytes of str are valid
* (except for the last MIN_MATCH-1 bytes of the input file).
*/
#define INSERT_STRING(s, str, match_head) \
(UPDATE_HASH(s, s->ins_h, s->window[(str) + MIN_MATCH-1]), \
s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
s->head[s->ins_h] = (str))
/* ========================================================================= */
int deflateInit (strm, level)
z_stream *strm;
int level;
{
return deflateInit2 (strm, level, DEFLATED, WBITS, MEM_LEVEL, 0);
/* To do: ignore strm->next_in if we use it as window */
}
/* ========================================================================= */
int deflateInit2 (strm, level, method, windowBits, memLevel, strategy)
z_stream *strm;
int level;
int method;
int windowBits;
int memLevel;
int strategy;
{
deflate_state *s;
int noheader = 0;
if (strm == Z_NULL) return Z_STREAM_ERROR;
strm->msg = Z_NULL;
if (strm->zalloc == Z_NULL) strm->zalloc = zcalloc;
if (strm->zfree == Z_NULL) strm->zfree = zcfree;
if (level == Z_DEFAULT_COMPRESSION) level = 6;
if (windowBits < 0) { /* undocumented feature: suppress zlib header */
noheader = 1;
windowBits = -windowBits;
}
if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != DEFLATED ||
windowBits < 8 || windowBits > 15 || level < 1 || level > 9) {
return Z_STREAM_ERROR;
}
s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
if (s == Z_NULL) return Z_MEM_ERROR;
strm->state = (struct internal_state *)s;
s->strm = strm;
s->noheader = noheader;
s->w_bits = windowBits;
s->w_size = 1 << s->w_bits;
s->hash_bits = memLevel + 7;
s->hash_size = 1 << s->hash_bits;
s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
s->window = (Byte*) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
s->prev = (Pos*) ZALLOC(strm, s->w_size, sizeof(Pos));
s->head = (Pos*) ZALLOC(strm, s->hash_size, sizeof(Pos));
s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
s->pending_buf = (uch*) ZALLOC(strm, s->lit_bufsize, 2*sizeof(ush));
if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
s->pending_buf == Z_NULL) {
strm->msg = z_errmsg[1-Z_MEM_ERROR];
deflateEnd (strm);
return Z_MEM_ERROR;
}
s->d_buf = (ush*) &(s->pending_buf[s->lit_bufsize]);
s->l_buf = (uch*) &(s->pending_buf[3*s->lit_bufsize]);
/* We overlay pending_buf and d_buf+l_buf. This works since the average
* output size for (length,distance) codes is <= 32 bits (worst case
* is 15+15+13=33).
*/
s->level = level;
s->strategy = strategy;
s->method = method;
return deflateReset(strm);
}
/* ========================================================================= */
int deflateReset (strm)
z_stream *strm;
{
deflate_state *s;
if (strm == Z_NULL || strm->state == Z_NULL ||
strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
strm->total_in = strm->total_out = 0;
strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
strm->data_type = Z_UNKNOWN;
s = (deflate_state *)strm->state;
s->pending = 0;
s->pending_out = s->pending_buf;
s->status = s->noheader ? BUSY_STATE : INIT_STATE;
s->adler = 1;
ct_init(s);
lm_init(s);
return Z_OK;
}
/* =========================================================================
* Put a short the pending_out buffer. The 16-bit value is put in MSB order.
* IN assertion: the stream state is correct and there is enough room in
* the pending_out buffer.
*/
local void putShortMSB (s, b)
deflate_state *s;
uInt b;
{
put_byte(s, b >> 8);
put_byte(s, b & 0xff);
}
/* =========================================================================
* Flush as much pending output as possible.
*/
local void flush_pending(strm)
z_stream *strm;
{
unsigned len = strm->state->pending;
if (len > strm->avail_out) len = strm->avail_out;
if (len == 0) return;
zmemcpy(strm->next_out, strm->state->pending_out, len);
strm->next_out += len;
strm->state->pending_out += len;
strm->total_out += len;
strm->avail_out -= len;
strm->state->pending -= len;
if (strm->state->pending == 0) {
strm->state->pending_out = strm->state->pending_buf;
}
}
/* ========================================================================= */
int deflate (strm, flush)
z_stream *strm;
int flush;
{
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
if (strm->next_out == Z_NULL || strm->next_in == Z_NULL) {
ERR_RETURN(strm, Z_STREAM_ERROR);
}
if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
strm->state->strm = strm; /* just in case */
/* Write the zlib header */
if (strm->state->status == INIT_STATE) {
uInt header = (DEFLATED + ((strm->state->w_bits-8)<<4)) << 8;
uInt level_flags = (strm->state->level-1) >> 1;
if (level_flags > 3) level_flags = 3;
header |= (level_flags << 6);
header += 31 - (header % 31);
strm->state->status = BUSY_STATE;
putShortMSB(strm->state, header);
}
/* Flush as much pending output as possible */
if (strm->state->pending != 0) {
flush_pending(strm);
if (strm->avail_out == 0) return Z_OK;
}
/* User must not provide more input after the first FINISH: */
if (strm->state->status == FINISH_STATE && strm->avail_in != 0) {
ERR_RETURN(strm, Z_BUF_ERROR);
}
/* Start a new block or continue the current one.
*/
if (strm->avail_in != 0 ||
(flush == Z_FINISH && strm->state->status != FINISH_STATE)) {
if (flush == Z_FINISH) {
strm->state->status = FINISH_STATE;
}
if (strm->state->level <= 3) {
if (deflate_fast(strm->state, flush)) return Z_OK;
} else {
if (deflate_slow(strm->state, flush)) return Z_OK;
}
}
Assert(strm->avail_out > 0, "bug2");
if (flush != Z_FINISH || strm->state->noheader) return Z_OK;
/* Write the zlib trailer (adler32) */
putShortMSB(strm->state, strm->state->adler >> 16);
putShortMSB(strm->state, strm->state->adler & 0xffff);
flush_pending(strm);
/* If avail_out is zero, the application will call deflate again
* to flush the rest.
*/
strm->state->noheader = 1; /* write the trailer only once! */
return Z_OK;
}
/* ========================================================================= */
int deflateEnd (strm)
z_stream *strm;
{
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
TRY_FREE(strm, strm->state->window);
TRY_FREE(strm, strm->state->prev);
TRY_FREE(strm, strm->state->head);
TRY_FREE(strm, strm->state->pending_buf);
ZFREE(strm, strm->state);
strm->state = Z_NULL;
return Z_OK;
}
/* ========================================================================= */
int deflateCopy (dest, source)
z_stream *dest;
z_stream *source;
{
if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
return Z_STREAM_ERROR;
}
*dest = *source;
return Z_STREAM_ERROR; /* to be implemented */
#if 0
dest->state = (struct internal_state *)
(*dest->zalloc)(1, sizeof(deflate_state));
if (dest->state == Z_NULL) return Z_MEM_ERROR;
*(dest->state) = *(source->state);
return Z_OK;
#endif
}
/* ===========================================================================
* Read a new buffer from the current input stream, update the adler32
* and total number of bytes read.
*/
local int read_buf(strm, buf, size)
z_stream *strm;
char *buf;
unsigned size;
{
unsigned len = strm->avail_in;
if (len > size) len = size;
if (len == 0) return 0;
strm->avail_in -= len;
if (!strm->state->noheader) {
strm->state->adler = adler32(strm->state->adler, strm->next_in, len);
}
zmemcpy(buf, strm->next_in, len);
strm->next_in += len;
strm->total_in += len;
return (int)len;
}
/* ===========================================================================
* Initialize the "longest match" routines for a new zlib stream
*/
local void lm_init (s)
deflate_state *s;
{
register unsigned j;
s->window_size = (ulg)2L*s->w_size;
/* Initialize the hash table (avoiding 64K overflow for 16 bit systems).
* prev[] will be initialized on the fly.
*/
s->head[s->hash_size-1] = NIL;
zmemzero((char*)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
/* Set the default configuration parameters:
*/
s->max_lazy_match = configuration_table[s->level].max_lazy;
s->good_match = configuration_table[s->level].good_length;
s->nice_match = configuration_table[s->level].nice_length;
s->max_chain_length = configuration_table[s->level].max_chain;
s->strstart = 0;
s->block_start = 0L;
s->lookahead = 0;
s->match_length = MIN_MATCH-1;
s->match_available = 0;
#ifdef ASMV
match_init(); /* initialize the asm code */
#endif
s->ins_h = 0;
for (j=0; j<MIN_MATCH-1; j++) UPDATE_HASH(s, s->ins_h, s->window[j]);
/* If lookahead < MIN_MATCH, ins_h is garbage, but this is
* not important since only literal bytes will be emitted.
*/
}
/* ===========================================================================
* Set match_start to the longest match starting at the given string and
* return its length. Matches shorter or equal to prev_length are discarded,
* in which case the result is equal to prev_length and match_start is
* garbage.
* IN assertions: cur_match is the head of the hash chain for the current
* string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
*/
#ifndef ASMV
/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
* match.S. The code will be functionally equivalent.
*/
local int longest_match(s, cur_match)
deflate_state *s;
IPos cur_match; /* current match */
{
unsigned chain_length = s->max_chain_length;/* max hash chain length */
register Byte *scan = s->window + s->strstart; /* current string */
register Byte *match; /* matched string */
register int len; /* length of current match */
int best_len = s->prev_length; /* best match length so far */
IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
s->strstart - (IPos)MAX_DIST(s) : NIL;
/* Stop when cur_match becomes <= limit. To simplify the code,
* we prevent matches with the string of window index 0.
*/
#ifdef UNALIGNED_OK
/* Compare two bytes at a time. Note: this is not always beneficial.
* Try with and without -DUNALIGNED_OK to check.
*/
register Byte *strend = s->window + s->strstart + MAX_MATCH - 1;
register ush scan_start = *(ush*)scan;
register ush scan_end = *(ush*)(scan+best_len-1);
#else
register Byte *strend = s->window + s->strstart + MAX_MATCH;
register Byte scan_end1 = scan[best_len-1];
register Byte scan_end = scan[best_len];
#endif
/* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
* It is easy to get rid of this optimization if necessary.
*/
Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
/* Do not waste too much time if we already have a good match: */
if (s->prev_length >= s->good_match) {
chain_length >>= 2;
}
Assert(s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
do {
Assert(cur_match < s->strstart, "no future");
match = s->window + cur_match;
/* Skip to next match if the match length cannot increase
* or if the match length is less than 2:
*/
#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
/* This code assumes sizeof(unsigned short) == 2. Do not use
* UNALIGNED_OK if your compiler uses a different size.
*/
if (*(ush*)(match+best_len-1) != scan_end ||
*(ush*)match != scan_start) continue;
/* It is not necessary to compare scan[2] and match[2] since they are
* always equal when the other bytes match, given that the hash keys
* are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
* strstart+3, +5, ... up to strstart+257. We check for insufficient
* lookahead only every 4th comparison; the 128th check will be made
* at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
* necessary to put more guard bytes at the end of the window, or
* to check more often for insufficient lookahead.
*/
scan++, match++;
do {
} while (*(ush*)(scan+=2) == *(ush*)(match+=2) &&
*(ush*)(scan+=2) == *(ush*)(match+=2) &&
*(ush*)(scan+=2) == *(ush*)(match+=2) &&
*(ush*)(scan+=2) == *(ush*)(match+=2) &&
scan < strend);
/* The funny "do {}" generates better code on most compilers */
/* Here, scan <= window+strstart+257 */
Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
if (*scan == *match) scan++;
len = (MAX_MATCH - 1) - (int)(strend-scan);
scan = strend - (MAX_MATCH-1);
#else /* UNALIGNED_OK */
if (match[best_len] != scan_end ||
match[best_len-1] != scan_end1 ||
*match != *scan ||
*++match != scan[1]) continue;
/* The check at best_len-1 can be removed because it will be made
* again later. (This heuristic is not always a win.)
* It is not necessary to compare scan[2] and match[2] since they
* are always equal when the other bytes match, given that
* the hash keys are equal and that HASH_BITS >= 8.
*/
scan += 2, match++;
/* We check for insufficient lookahead only every 8th comparison;
* the 256th check will be made at strstart+258.
*/
do {
} while (*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
scan < strend);
Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
len = MAX_MATCH - (int)(strend - scan);
scan = strend - MAX_MATCH;
#endif /* UNALIGNED_OK */
if (len > best_len) {
s->match_start = cur_match;
best_len = len;
if (len >= s->nice_match) break;
#ifdef UNALIGNED_OK
scan_end = *(ush*)(scan+best_len-1);
#else
scan_end1 = scan[best_len-1];
scan_end = scan[best_len];
#endif
}
} while ((cur_match = s->prev[cur_match & s->w_mask]) > limit
&& --chain_length != 0);
return best_len;
}
#endif /* ASMV */
#ifdef DEBUG
/* ===========================================================================
* Check that the match at match_start is indeed a match.
*/
local void check_match(s, start, match, length)
deflate_state *s;
IPos start, match;
int length;
{
/* check that the match is indeed a match */
if (memcmp((char*)s->window + match,
(char*)s->window + start, length) != EQUAL) {
fprintf(stderr,
" start %d, match %d, length %d\n",
start, match, length);
z_error("invalid match");
}
if (verbose > 1) {
fprintf(stderr,"\\[%d,%d]", start-match, length);
do { putc(s->window[start++], stderr); } while (--length != 0);
}
}
#else
# define check_match(s, start, match, length)
#endif
/* ===========================================================================
* Fill the window when the lookahead becomes insufficient.
* Updates strstart and lookahead.
*
* IN assertion: lookahead < MIN_LOOKAHEAD
* OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
* At least one byte has been read, or avail_in == 0; reads are
* performed for at least two bytes (required for the zip translate_eol
* option -- not supported here).
*/
local void fill_window(s)
deflate_state *s;
{
register unsigned n, m;
unsigned more; /* Amount of free space at the end of the window. */
do {
more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
/* Deal with !@#$% 64K limit: */
if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
more = s->w_size;
} else if (more == (unsigned)(-1)) {
/* Very unlikely, but possible on 16 bit machine if strstart == 0
* and lookahead == 1 (input done one byte at time)
*/
more--;
/* If the window is almost full and there is insufficient lookahead,
* move the upper half to the lower one to make room in the upper half.
*/
} else if (s->strstart >= s->w_size+MAX_DIST(s)) {
/* By the IN assertion, the window is not empty so we can't confuse
* more == 0 with more == 64K on a 16 bit machine.
*/
memcpy((char*)s->window, (char*)s->window+s->w_size,
(unsigned)s->w_size);
s->match_start -= s->w_size;
s->strstart -= s->w_size; /* we now have strstart >= MAX_DIST */
s->block_start -= (long) s->w_size;
for (n = 0; n < s->hash_size; n++) {
m = s->head[n];
s->head[n] = (Pos)(m >= s->w_size ? m-s->w_size : NIL);
}
for (n = 0; n < s->w_size; n++) {
m = s->prev[n];
s->prev[n] = (Pos)(m >= s->w_size ? m-s->w_size : NIL);
/* If n is not on any hash chain, prev[n] is garbage but
* its value will never be used.
*/
}
more += s->w_size;
}
if (s->strm->avail_in == 0) return;
/* If there was no sliding:
* strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
* more == window_size - lookahead - strstart
* => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
* => more >= window_size - 2*WSIZE + 2
* In the BIG_MEM or MMAP case (not yet supported),
* window_size == input_size + MIN_LOOKAHEAD &&
* strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
* Otherwise, window_size == 2*WSIZE so more >= 2.
* If there was sliding, more >= WSIZE. So in all cases, more >= 2.
*/
Assert(more >= 2, "more < 2");
n = read_buf(s->strm, (char*)s->window + s->strstart + s->lookahead,
more);
s->lookahead += n;
} while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
}
/* ===========================================================================
* Flush the current block, with given end-of-file flag.
* IN assertion: strstart is set to the end of the current match.
*/
#define FLUSH_BLOCK_ONLY(s, eof) { \
ct_flush_block(s, (s->block_start >= 0L ? \
(char*)&s->window[(unsigned)s->block_start] : \
(char*)Z_NULL), (long)s->strstart - s->block_start, (eof)); \
s->block_start = s->strstart; \
flush_pending(s->strm); \
}
/* Same but force premature exit if necessary. */
#define FLUSH_BLOCK(s, eof) { \
FLUSH_BLOCK_ONLY(s, eof); \
if (s->strm->avail_out == 0) return 1; \
}
/* ===========================================================================
* Compress as much as possible from the input stream, return true if
* processing was terminated prematurely (no more input or output space).
* This function does not perform lazy evaluationof matches and inserts
* new strings in the dictionary only for unmatched strings or for short
* matches. It is used only for the fast compression options.
*/
local int deflate_fast(s, flush)
deflate_state *s;
int flush;
{
IPos hash_head; /* head of the hash chain */
int bflush; /* set if current block must be flushed */
s->prev_length = MIN_MATCH-1;
for (;;) {
/* Make sure that we always have enough lookahead, except
* at the end of the input file. We need MAX_MATCH bytes
* for the next match, plus MIN_MATCH bytes to insert the
* string following the next match.
*/
if (s->lookahead < MIN_LOOKAHEAD) {
fill_window(s);
if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1;
if (s->lookahead == 0) break; /* flush the current block */
}
/* Insert the string window[strstart .. strstart+2] in the
* dictionary, and set hash_head to the head of the hash chain:
*/
INSERT_STRING(s, s->strstart, hash_head);
/* Find the longest match, discarding those <= prev_length.
* At this point we have always match_length < MIN_MATCH
*/
if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
/* To simplify the code, we prevent matches with the string
* of window index 0 (in particular we have to avoid a match
* of the string with itself at the start of the input file).
*/
if (s->strategy != Z_HUFFMAN_ONLY) {
s->match_length = longest_match (s, hash_head);
}
/* longest_match() sets match_start */
if (s->match_length > s->lookahead) s->match_length = s->lookahead;
}
if (s->match_length >= MIN_MATCH) {
check_match(s, s->strstart, s->match_start, s->match_length);
bflush = ct_tally(s, s->strstart - s->match_start,
s->match_length - MIN_MATCH);
s->lookahead -= s->match_length;
/* Insert new strings in the hash table only if the match length
* is not too large. This saves time but degrades compression.
*/
if (s->match_length <= s->max_insert_length) {
s->match_length--; /* string at strstart already in hash table */
do {
s->strstart++;
INSERT_STRING(s, s->strstart, hash_head);
/* strstart never exceeds WSIZE-MAX_MATCH, so there are
* always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
* these bytes are garbage, but it does not matter since
* the next lookahead bytes will be emitted as literals.
*/
} while (--s->match_length != 0);
s->strstart++;
} else {
s->strstart += s->match_length;
s->match_length = 0;
s->ins_h = s->window[s->strstart];
UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
#if MIN_MATCH != 3
Call UPDATE_HASH() MIN_MATCH-3 more times
#endif
}
} else {
/* No match, output a literal byte */
Tracevv((stderr,"%c", s->window[s->strstart]));
bflush = ct_tally (s, 0, s->window[s->strstart]);
s->lookahead--;
s->strstart++;
}
if (bflush) FLUSH_BLOCK(s, 0);
}
FLUSH_BLOCK(s, flush == Z_FINISH);
return 0; /* normal exit */
}
/* ===========================================================================
* Same as above, but achieves better compression. We use a lazy
* evaluation for matches: a match is finally adopted only if there is
* no better match at the next window position.
*/
local int deflate_slow(s, flush)
deflate_state *s;
int flush;
{
IPos hash_head; /* head of hash chain */
int bflush; /* set if current block must be flushed */
/* Process the input block. */
for (;;) {
/* Make sure that we always have enough lookahead, except
* at the end of the input file. We need MAX_MATCH bytes
* for the next match, plus MIN_MATCH bytes to insert the
* string following the next match.
*/
if (s->lookahead < MIN_LOOKAHEAD) {
fill_window(s);
if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1;
if (s->lookahead == 0) break; /* flush the current block */
}
/* Insert the string window[strstart .. strstart+2] in the
* dictionary, and set hash_head to the head of the hash chain:
*/
INSERT_STRING(s, s->strstart, hash_head);
/* Find the longest match, discarding those <= prev_length.
*/
s->prev_length = s->match_length, s->prev_match = s->match_start;
s->match_length = MIN_MATCH-1;
if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
s->strstart - hash_head <= MAX_DIST(s)) {
/* To simplify the code, we prevent matches with the string
* of window index 0 (in particular we have to avoid a match
* of the string with itself at the start of the input file).
*/
if (s->strategy != Z_HUFFMAN_ONLY) {
s->match_length = longest_match (s, hash_head);
}
/* longest_match() sets match_start */
if (s->match_length > s->lookahead) s->match_length = s->lookahead;
if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
(s->match_length == MIN_MATCH &&
s->strstart - s->match_start > TOO_FAR))) {
/* If prev_match is also MIN_MATCH, match_start is garbage
* but we will ignore the current match anyway.
*/
s->match_length = MIN_MATCH-1;
}
}
/* If there was a match at the previous step and the current
* match is not better, output the previous match:
*/
if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
check_match(s, s->strstart-1, s->prev_match, s->prev_length);
bflush = ct_tally(s, s->strstart -1 - s->prev_match,
s->prev_length - MIN_MATCH);
/* Insert in hash table all strings up to the end of the match.
* strstart-1 and strstart are already inserted.
*/
s->lookahead -= s->prev_length-1;
s->prev_length -= 2;
do {
s->strstart++;
INSERT_STRING(s, s->strstart, hash_head);
/* strstart never exceeds WSIZE-MAX_MATCH, so there are
* always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
* these bytes are garbage, but it does not matter since the
* next lookahead bytes will always be emitted as literals.
*/
} while (--s->prev_length != 0);
s->match_available = 0;
s->match_length = MIN_MATCH-1;
s->strstart++;
if (bflush) FLUSH_BLOCK(s, 0);
} else if (s->match_available) {
/* If there was no match at the previous position, output a
* single literal. If there was a match but the current match
* is longer, truncate the previous match to a single literal.
*/
Tracevv((stderr,"%c", s->window[s->strstart-1]));
if (ct_tally (s, 0, s->window[s->strstart-1])) {
FLUSH_BLOCK_ONLY(s, 0);
}
s->strstart++;
s->lookahead--;
if (s->strm->avail_out == 0) return 1;
} else {
/* There is no previous match to compare with, wait for
* the next step to decide.
*/
s->match_available = 1;
s->strstart++;
s->lookahead--;
}
}
if (s->match_available) ct_tally (s, 0, s->window[s->strstart-1]);
FLUSH_BLOCK(s, flush == Z_FINISH);
return 0;
}

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/* deflate.h -- internal compression state
* Copyright (C) 1995 Jean-loup Gailly
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
/* $Id: deflate.h,v 1.3 1995/04/14 12:39:45 jloup Exp $ */
#include "zutil.h"
/* ===========================================================================
* Internal compression state.
*/
/* Data type */
#define BINARY 0
#define ASCII 1
#define UNKNOWN 2
#define LENGTH_CODES 29
/* number of length codes, not counting the special END_BLOCK code */
#define LITERALS 256
/* number of literal bytes 0..255 */
#define L_CODES (LITERALS+1+LENGTH_CODES)
/* number of Literal or Length codes, including the END_BLOCK code */
#define D_CODES 30
/* number of distance codes */
#define BL_CODES 19
/* number of codes used to transfer the bit lengths */
#define HEAP_SIZE (2*L_CODES+1)
/* maximum heap size */
#define MAX_BITS 15
/* All codes must not exceed MAX_BITS bits */
#define INIT_STATE 42
#define BUSY_STATE 113
#define FINISH_STATE 666
/* Stream status */
/* Data structure describing a single value and its code string. */
typedef struct ct_data_s {
union {
ush freq; /* frequency count */
ush code; /* bit string */
} fc;
union {
ush dad; /* father node in Huffman tree */
ush len; /* length of bit string */
} dl;
} ct_data;
#define Freq fc.freq
#define Code fc.code
#define Dad dl.dad
#define Len dl.len
typedef struct static_tree_desc_s static_tree_desc;
typedef struct tree_desc_s {
ct_data *dyn_tree; /* the dynamic tree */
int max_code; /* largest code with non zero frequency */
static_tree_desc *stat_desc; /* the corresponding static tree */
} tree_desc;
typedef ush Pos;
typedef unsigned IPos;
/* A Pos is an index in the character window. We use short instead of int to
* save space in the various tables. IPos is used only for parameter passing.
*/
typedef struct internal_state {
z_stream *strm; /* pointer back to this zlib stream */
int status; /* as the name implies */
Byte *pending_buf; /* output still pending */
Byte *pending_out; /* next pending byte to output to the stream */
int pending; /* nb of bytes in the pending buffer */
uLong adler; /* adler32 of uncompressed data */
int noheader; /* suppress zlib header and adler32 */
Byte data_type; /* UNKNOWN, BINARY or ASCII */
Byte method; /* STORED (for zip only) or DEFLATED */
/* used by deflate.c: */
uInt w_size; /* LZ77 window size (32K by default) */
uInt w_bits; /* log2(w_size) (8..16) */
uInt w_mask; /* w_size - 1 */
Byte *window;
/* Sliding window. Input bytes are read into the second half of the window,
* and move to the first half later to keep a dictionary of at least wSize
* bytes. With this organization, matches are limited to a distance of
* wSize-MAX_MATCH bytes, but this ensures that IO is always
* performed with a length multiple of the block size. Also, it limits
* the window size to 64K, which is quite useful on MSDOS.
* To do: use the user input buffer as sliding window.
*/
ulg window_size;
/* Actual size of window: 2*wSize, except when the user input buffer
* is directly used as sliding window.
*/
Pos *prev;
/* Link to older string with same hash index. To limit the size of this
* array to 64K, this link is maintained only for the last 32K strings.
* An index in this array is thus a window index modulo 32K.
*/
Pos *head; /* Heads of the hash chains or NIL. */
uInt ins_h; /* hash index of string to be inserted */
uInt hash_size; /* number of elements in hash table */
uInt hash_bits; /* log2(hash_size) */
uInt hash_mask; /* hash_size-1 */
uInt hash_shift;
/* Number of bits by which ins_h must be shifted at each input
* step. It must be such that after MIN_MATCH steps, the oldest
* byte no longer takes part in the hash key, that is:
* hash_shift * MIN_MATCH >= hash_bits
*/
long block_start;
/* Window position at the beginning of the current output block. Gets
* negative when the window is moved backwards.
*/
uInt match_length; /* length of best match */
IPos prev_match; /* previous match */
int match_available; /* set if previous match exists */
uInt strstart; /* start of string to insert */
uInt match_start; /* start of matching string */
uInt lookahead; /* number of valid bytes ahead in window */
uInt prev_length;
/* Length of the best match at previous step. Matches not greater than this
* are discarded. This is used in the lazy match evaluation.
*/
uInt max_chain_length;
/* To speed up deflation, hash chains are never searched beyond this
* length. A higher limit improves compression ratio but degrades the
* speed.
*/
uInt max_lazy_match;
/* Attempt to find a better match only when the current match is strictly
* smaller than this value. This mechanism is used only for compression
* levels >= 4.
*/
# define max_insert_length max_lazy_match
/* Insert new strings in the hash table only if the match length is not
* greater than this length. This saves time but degrades compression.
* max_insert_length is used only for compression levels <= 3.
*/
int level; /* compression level (1..9) */
int strategy; /* favor or force Huffman coding*/
uInt good_match;
/* Use a faster search when the previous match is longer than this */
int nice_match; /* Stop searching when current match exceeds this */
/* used by trees.c: */
ct_data dyn_ltree[HEAP_SIZE]; /* literal and length tree */
ct_data dyn_dtree[2*D_CODES+1]; /* distance tree */
ct_data bl_tree[2*BL_CODES+1]; /* Huffman tree for the bit lengths */
tree_desc l_desc; /* descriptor for literal tree */
tree_desc d_desc; /* descriptor for distance tree */
tree_desc bl_desc; /* descriptor for bit length tree */
ush bl_count[MAX_BITS+1];
/* number of codes at each bit length for an optimal tree */
int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
int heap_len; /* number of elements in the heap */
int heap_max; /* element of largest frequency */
/* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
* The same heap array is used to build all trees.
*/
uch depth[2*L_CODES+1];
/* Depth of each subtree used as tie breaker for trees of equal frequency
*/
uch *l_buf; /* buffer for literals or lengths */
uInt lit_bufsize;
/* Size of match buffer for literals/lengths. There are 4 reasons for
* limiting lit_bufsize to 64K:
* - frequencies can be kept in 16 bit counters
* - if compression is not successful for the first block, all input
* data is still in the window so we can still emit a stored block even
* when input comes from standard input. (This can also be done for
* all blocks if lit_bufsize is not greater than 32K.)
* - if compression is not successful for a file smaller than 64K, we can
* even emit a stored file instead of a stored block (saving 5 bytes).
* This is applicable only for zip (not gzip or zlib).
* - creating new Huffman trees less frequently may not provide fast
* adaptation to changes in the input data statistics. (Take for
* example a binary file with poorly compressible code followed by
* a highly compressible string table.) Smaller buffer sizes give
* fast adaptation but have of course the overhead of transmitting
* trees more frequently.
* - I can't count above 4
*/
uInt last_lit; /* running index in l_buf */
ush *d_buf;
/* Buffer for distances. To simplify the code, d_buf and l_buf have
* the same number of elements. To use different lengths, an extra flag
* array would be necessary.
*/
ulg opt_len; /* bit length of current block with optimal trees */
ulg static_len; /* bit length of current block with static trees */
ulg compressed_len; /* total bit length of compressed file */
uInt matches; /* number of string matches in current block */
#ifdef DEBUG
ulg bits_sent; /* bit length of the compressed data */
#endif
ush bi_buf;
/* Output buffer. bits are inserted starting at the bottom (least
* significant bits).
*/
int bi_valid;
/* Number of valid bits in bi_buf. All bits above the last valid bit
* are always zero.
*/
} deflate_state;
/* Output a byte on the stream.
* IN assertion: there is enough room in pending_buf.
*/
#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
/* Minimum amount of lookahead, except at the end of the input file.
* See deflate.c for comments about the MIN_MATCH+1.
*/
#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
/* In order to simplify the code, particularly on 16 bit machines, match
* distances are limited to MAX_DIST instead of WSIZE.
*/
/* in trees.c */
void ct_init __P((deflate_state *s));
int ct_tally __P((deflate_state *s, int dist, int lc));
ulg ct_flush_block __P((deflate_state *s, char *buf, ulg stored_len, int eof));

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/* example.c -- usage example of the zlib compression library
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: example.c,v 1.4 1995/04/14 13:32:49 jloup Exp $ */
#include <stdio.h>
#include "zlib.h"
#define BUFLEN 4096
#define local static
/* For MSDOS and other systems with limitation on stack size. For Unix,
#define local
works also.
*/
#define CHECK_ERR(err, msg) { \
if (err != Z_OK) { \
fprintf(stderr, "%s error: %d\n", msg, err); \
exit(1); \
} \
}
char *hello = "hello world";
/* ===========================================================================
* Test compress() and uncompress()
*/
void test_compress()
{
local Byte compr[BUFLEN];
uLong comprLen = sizeof(compr);
local Byte uncompr[BUFLEN];
uLong uncomprLen = sizeof(uncompr);
int err;
uLong len = strlen(hello)+1;
err = compress(compr, &comprLen, hello, len);
CHECK_ERR(err, "compress");
strcpy(uncompr, "garbage");
err = uncompress(uncompr, &uncomprLen, compr, comprLen);
CHECK_ERR(err, "uncompress");
if (strcmp(uncompr, hello)) {
fprintf(stderr, "bad uncompress\n");
} else {
printf("uncompress(): %s\n", uncompr);
}
}
/* ===========================================================================
* Test read/write of .gz files
*/
void test_gzio(out, in)
char *out; /* output file */
char *in; /* input file */
{
local Byte uncompr[BUFLEN];
uLong uncomprLen = sizeof(uncompr);
int err;
int len = strlen(hello)+1;
gzFile file;
file = gzopen(out, "wb");
if (file == NULL) {
fprintf(stderr, "gzopen error\n");
exit(1);
}
if (gzwrite(file, hello, len) != len) {
fprintf(stderr, "gzwrite err: %s\n", gzerror(file, &err));
}
gzclose(file);
file = gzopen(in, "rb");
if (file == NULL) {
fprintf(stderr, "gzopen error\n");
}
strcpy(uncompr, "garbage");
uncomprLen = gzread(file, uncompr, uncomprLen);
if (uncomprLen != len) {
fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
}
gzclose(file);
if (strcmp(uncompr, hello)) {
fprintf(stderr, "bad gzread\n");
} else {
printf("gzread(): %s\n", uncompr);
}
}
/* ===========================================================================
* Test deflate() with small buffers, return the compressed length.
*/
uLong test_deflate(compr)
Byte compr[];
{
z_stream c_stream; /* compression stream */
int err;
int len = strlen(hello)+1;
c_stream.zalloc = (alloc_func)0;
c_stream.zfree = (free_func)0;
err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
CHECK_ERR(err, "deflateInit");
c_stream.next_in = (Byte*)hello;
c_stream.next_out = compr;
while (c_stream.total_in != len) {
c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
err = deflate(&c_stream, Z_NO_FLUSH);
CHECK_ERR(err, "deflate");
}
/* Finish the stream, still forcing small buffers: */
do {
c_stream.avail_out = 1;
err = deflate(&c_stream, Z_FINISH);
CHECK_ERR(err, "deflate");
} while (c_stream.avail_out == 0);
err = deflateEnd(&c_stream);
CHECK_ERR(err, "deflateEnd");
return c_stream.total_out;
}
/* ===========================================================================
* Test inflate() with small buffers
*/
void test_inflate(compr)
Byte compr[];
{
local Byte uncompr[BUFLEN];
int err;
z_stream d_stream; /* decompression stream */
strcpy(uncompr, "garbage");
d_stream.zalloc = (alloc_func)0;
d_stream.zfree = (free_func)0;
err = inflateInit(&d_stream);
CHECK_ERR(err, "inflateInit");
d_stream.next_in = compr;
d_stream.next_out = uncompr;
for (;;) {
d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
err = inflate(&d_stream, Z_NO_FLUSH);
if (err == Z_STREAM_END) break;
CHECK_ERR(err, "inflate");
}
err = inflateEnd(&d_stream);
CHECK_ERR(err, "inflateEnd");
if (strcmp(uncompr, hello)) {
fprintf(stderr, "bad inflate\n");
} else {
printf("inflate(): %s\n", uncompr);
}
}
/* ===========================================================================
* Usage: example [output.gz [input.gz]]
*/
void main(argc, argv)
int argc;
char *argv[];
{
local Byte compr[BUFLEN];
uLong comprLen;
if (zlib_version[0] != ZLIB_VERSION[0]) {
fprintf(stderr, "incompatible zlib version\n");
exit(1);
} else if (strcmp(zlib_version, ZLIB_VERSION) != 0) {
fprintf(stderr, "warning: different zlib version\n");
}
test_compress();
test_gzio((argc > 1 ? argv[1] : "foo.gz"),
(argc > 2 ? argv[2] : "foo.gz"));
comprLen = test_deflate(compr);
test_inflate(compr);
exit(0);
}

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/* gzio.c -- IO on .gz files
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: gzio.c,v 1.4 1995/04/14 14:50:52 jloup Exp $ */
#include <stdio.h>
#include "zutil.h"
struct internal_state {int dummy;}; /* for buggy compilers */
#define Z_BUFSIZE 4096
#define ALLOC(size) zcalloc((voidp)0, 1, size)
#define TRYFREE(p) {if (p) zcfree((voidp)0, p);}
#define GZ_MAGIC_1 0x1f
#define GZ_MAGIC_2 0x8b
/* gzip flag byte */
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */
#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
#define COMMENT 0x10 /* bit 4 set: file comment present */
#define RESERVED 0xE0 /* bits 5..7: reserved */
#ifndef SEEK_CUR
# define SEEK_CUR 1
#endif
typedef struct gz_stream {
z_stream stream;
int z_err; /* error code for last stream operation */
int z_eof; /* set if end of input file */
FILE *file; /* .gz file */
Byte *inbuf; /* input buffer */
Byte *outbuf; /* output buffer */
uLong crc; /* crc32 of uncompressed data */
char *msg; /* error message */
char *path; /* path name for debugging only */
int transparent; /* 1 if input file is not a .gz file */
char mode; /* 'w' or 'r' */
} gz_stream;
/* ===========================================================================
* Cleanup then free the given gz_stream. Return a zlib error code.
*/
local int destroy (s)
gz_stream *s;
{
int err = Z_OK;
if (!s) return Z_STREAM_ERROR;
TRYFREE(s->inbuf);
TRYFREE(s->outbuf);
TRYFREE(s->path);
TRYFREE(s->msg);
if (s->stream.state != NULL) {
if (s->mode == 'w') {
err = deflateEnd(&(s->stream));
} else if (s->mode == 'r') {
err = inflateEnd(&(s->stream));
}
}
if (s->file != NULL && fclose(s->file)) {
err = Z_ERRNO;
}
zcfree((voidp)0, s);
return s->z_err < 0 ? s->z_err : err;
}
/* ===========================================================================
Opens a gzip (.gz) file for reading or writing. The mode parameter
is as in fopen ("rb" or "wb"). The file is given either by file descritor
or path name (if fd == -1).
gz_open return NULL if the file could not be opened or if there was
insufficient memory to allocate the (de)compression state; errno
can be checked to distinguish the two cases (if errno is zero, the
zlib error is Z_MEM_ERROR).
*/
local gzFile gz_open (path, mode, fd)
char *path;
char *mode;
int fd;
{
int err;
char *p = mode;
gz_stream *s = (gz_stream *)ALLOC(sizeof(gz_stream));
if (!s) return Z_NULL;
s->stream.zalloc = (alloc_func)0;
s->stream.zfree = (free_func)0;
s->stream.next_in = s->inbuf = Z_NULL;
s->stream.next_out = s->outbuf = Z_NULL;
s->stream.avail_in = s->stream.avail_out = 0;
s->file = NULL;
s->z_err = Z_OK;
s->z_eof = 0;
s->crc = crc32(0L, Z_NULL, 0);
s->msg = NULL;
s->transparent = 0;
s->path = (char*)ALLOC(strlen(path)+1);
if (s->path == NULL) {
return destroy(s), (gzFile)Z_NULL;
}
strcpy(s->path, path); /* do this early for debugging */
s->mode = '\0';
do {
if (*p == 'r') s->mode = 'r';
if (*p == 'w') s->mode = 'w';
} while (*p++);
if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL;
if (s->mode == 'w') {
err = deflateInit2(&(s->stream), Z_DEFAULT_COMPRESSION,
DEFLATED, -WBITS, MEM_LEVEL, 0);
/* windowBits is passed < 0 to suppress zlib header */
s->stream.next_out = s->outbuf = ALLOC(Z_BUFSIZE);
if (err != Z_OK || s->outbuf == Z_NULL) {
return destroy(s), (gzFile)Z_NULL;
}
} else {
err = inflateInit2(&(s->stream), -WBITS);
s->stream.next_in = s->inbuf = ALLOC(Z_BUFSIZE);
if (err != Z_OK || s->inbuf == Z_NULL) {
return destroy(s), (gzFile)Z_NULL;
}
}
s->stream.avail_out = Z_BUFSIZE;
errno = 0;
s->file = fd < 0 ? FOPEN(path, mode) : fdopen(fd, mode);
if (s->file == NULL) {
return destroy(s), (gzFile)Z_NULL;
}
if (s->mode == 'w') {
/* Write a very simple .gz header:
*/
fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", GZ_MAGIC_1, GZ_MAGIC_2,
DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
} else {
/* Check and skip the header:
*/
Byte c1 = 0, c2 = 0;
Byte method = 0;
Byte flags = 0;
Byte xflags = 0;
Byte time[4];
Byte osCode;
int c;
s->stream.avail_in = fread(s->inbuf, 1, 2, s->file);
if (s->stream.avail_in != 2 || s->inbuf[0] != GZ_MAGIC_1
|| s->inbuf[1] != GZ_MAGIC_2) {
s->transparent = 1;
return (gzFile)s;
}
s->stream.avail_in = 0;
fscanf(s->file,"%c%c%4c%c%c", &method, &flags, time, &xflags, &osCode);
if (method != DEFLATED || feof(s->file) || (flags & RESERVED) != 0) {
s->z_err = Z_DATA_ERROR;
return (gzFile)s;
}
if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
long len;
fscanf(s->file, "%c%c", &c1, &c2);
len = c1 + ((long)c2<<8);
fseek(s->file, len, SEEK_CUR);
}
if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
while ((c = getc(s->file)) != 0 && c != EOF) ;
}
if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
while ((c = getc(s->file)) != 0 && c != EOF) ;
}
if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
fscanf(s->file, "%c%c", &c1, &c2);
}
if (feof(s->file)) {
s->z_err = Z_DATA_ERROR;
}
}
return (gzFile)s;
}
/* ===========================================================================
Opens a gzip (.gz) file for reading or writing.
*/
gzFile gzopen (path, mode)
char *path;
char *mode;
{
return gz_open (path, mode, -1);
}
/* ===========================================================================
Associate a gzFile with the file descriptor fd.
*/
gzFile gzdopen (fd, mode)
int fd;
char *mode;
{
char name[20];
sprintf(name, "_fd:%d_", fd); /* for debugging */
return gz_open (name, mode, fd);
}
/* ===========================================================================
Reads the given number of uncompressed bytes from the compressed file.
gzread returns the number of bytes actually read (0 for end of file).
*/
int gzread (file, buf, len)
gzFile file;
voidp buf;
unsigned len;
{
gz_stream *s = (gz_stream*)file;
if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;
if (s->transparent) {
unsigned n = 0;
/* Copy the first two (non-magic) bytes if not done already */
while (s->stream.avail_in > 0 && len > 0) {
*((Byte*)buf)++ = *s->stream.next_in++;
s->stream.avail_in--;
len--; n++;
}
if (len == 0) return n;
return n + fread(buf, 1, len, s->file);
}
if (s->z_err == Z_DATA_ERROR) return -1; /* bad .gz file */
if (s->z_err == Z_STREAM_END) return 0; /* don't read crc as data */
s->stream.next_out = buf;
s->stream.avail_out = len;
while (s->stream.avail_out != 0) {
if (s->stream.avail_in == 0 && !s->z_eof) {
errno = 0;
s->stream.avail_in =
fread(s->inbuf, 1, Z_BUFSIZE, s->file);
if (s->stream.avail_in == 0) {
s->z_eof = 1;
} else if (s->stream.avail_in == (uInt)EOF) {
s->stream.avail_in = 0;
s->z_eof = 1;
s->z_err = Z_ERRNO;
break;
}
s->stream.next_in = s->inbuf;
}
s->z_err = inflate(&(s->stream), Z_NO_FLUSH);
if (s->z_err == Z_STREAM_END ||
s->z_err != Z_OK || s->z_eof) break;
}
len -= s->stream.avail_out;
s->crc = crc32(s->crc, buf, len);
return len;
}
/* ===========================================================================
Writes the given number of uncompressed bytes into the compressed file.
gzwrite returns the number of bytes actually written (0 in case of error).
*/
int gzwrite (file, buf, len)
gzFile file;
voidp buf;
unsigned len;
{
gz_stream *s = (gz_stream*)file;
if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
s->stream.next_in = buf;
s->stream.avail_in = len;
while (s->stream.avail_in != 0) {
if (s->stream.avail_out == 0) {
s->stream.next_out = s->outbuf;
if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) {
s->z_err = Z_ERRNO;
break;
}
s->stream.avail_out = Z_BUFSIZE;
}
s->z_err = deflate(&(s->stream), Z_NO_FLUSH);
if (s->z_err != Z_OK) break;
}
s->crc = crc32(s->crc, buf, len);
return len - s->stream.avail_in;
}
/* ===========================================================================
Flushes all pending output into the compressed file. The parameter
flush is as in the deflate() function.
gzflush should be called only when strictly necessary because it can
degrade compression.
*/
int gzflush (file, flush)
gzFile file;
int flush;
{
uInt len;
int done = 0;
gz_stream *s = (gz_stream*)file;
if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
s->stream.avail_in = 0; /* should be zero already anyway */
for (;;) {
len = Z_BUFSIZE - s->stream.avail_out;
if (len != 0) {
if (fwrite(s->outbuf, 1, len, s->file) != len) {
s->z_err = Z_ERRNO;
break;
}
s->stream.next_out = s->outbuf;
s->stream.avail_out = Z_BUFSIZE;
}
if (done) break;
s->z_err = deflate(&(s->stream), flush);
if (s->z_err != Z_OK) break;
/* deflate has finished flushing only when it hasn't used up
* all the available space in the output buffer:
*/
done = (s->stream.avail_out != 0);
}
return s->z_err;
}
/* ===========================================================================
Outputs a long in LSB order to the given file
*/
local void putLong (file, x)
FILE *file;
uLong x;
{
int n;
for (n = 0; n < 4; n++) {
fputc(x & 0xff, file);
x >>= 8;
}
}
/* ===========================================================================
Reads a long in LSB order from the given buffer
*/
local uLong getLong (buf)
Byte *buf;
{
uLong x = 0;
Byte *p = buf+4;
do {
x <<= 8;
x |= *--p;
} while (p != buf);
return x;
}
/* ===========================================================================
Flushes all pending output if necessary, closes the compressed file
and deallocates all the (de)compression state.
*/
int gzclose (file)
gzFile file;
{
uInt n;
gz_stream *s = (gz_stream*)file;
if (s == NULL) return Z_STREAM_ERROR;
if (s->mode == 'w') {
gzflush (file, Z_FINISH);
putLong (s->file, s->crc);
putLong (s->file, s->stream.total_in);
} else if (s->mode == 'r' && s->z_err == Z_STREAM_END) {
/* slide CRC and original size if they are at the end of inbuf */
if ((n = s->stream.avail_in) < 8 && !s->z_eof) {
Byte *p = s->inbuf;
Byte *q = s->stream.next_in;
while (n--) { *p++ = *q++; };
n = s->stream.avail_in;
n += fread(p, 1, 8, s->file);
s->stream.next_in = s->inbuf;
}
/* check CRC and original size */
if (n < 8 ||
getLong(s->stream.next_in) != s->crc ||
getLong(s->stream.next_in + 4) != s->stream.total_out) {
s->z_err = Z_DATA_ERROR;
}
}
return destroy(file);
}
/* ===========================================================================
Returns the error message for the last error which occured on the
given compressed file. errnum is set to zlib error number. If an
error occured in the file system and not in the compression library,
errnum is set to Z_ERRNO and the application may consult errno
to get the exact error code.
*/
char* gzerror (file, errnum)
gzFile file;
int *errnum;
{
char *m;
gz_stream *s = (gz_stream*)file;
if (s == NULL) {
*errnum = Z_STREAM_ERROR;
return z_errmsg[1-Z_STREAM_ERROR];
}
*errnum = s->z_err;
if (*errnum == Z_OK) return "";
m = *errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg;
if (m == NULL || *m == '\0') m = z_errmsg[1-s->z_err];
TRYFREE(s->msg);
s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);
strcpy(s->msg, s->path);
strcat(s->msg, ": ");
strcat(s->msg, m);
return s->msg;
}

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/* infblock.c -- interpret and process block types to last block
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "infblock.h"
#include "inftrees.h"
#include "infcodes.h"
#include "infutil.h"
struct inflate_codes_state {int dummy;}; /* for buggy compilers */
/* Table for deflate from PKZIP's appnote.txt. */
local uInt border[] = { /* Order of the bit length code lengths */
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
/*
Notes beyond the 1.93a appnote.txt:
1. Distance pointers never point before the beginning of the output
stream.
2. Distance pointers can point back across blocks, up to 32k away.
3. There is an implied maximum of 7 bits for the bit length table and
15 bits for the actual data.
4. If only one code exists, then it is encoded using one bit. (Zero
would be more efficient, but perhaps a little confusing.) If two
codes exist, they are coded using one bit each (0 and 1).
5. There is no way of sending zero distance codes--a dummy must be
sent if there are none. (History: a pre 2.0 version of PKZIP would
store blocks with no distance codes, but this was discovered to be
too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
zero distance codes, which is sent as one code of zero bits in
length.
6. There are up to 286 literal/length codes. Code 256 represents the
end-of-block. Note however that the static length tree defines
288 codes just to fill out the Huffman codes. Codes 286 and 287
cannot be used though, since there is no length base or extra bits
defined for them. Similarily, there are up to 30 distance codes.
However, static trees define 32 codes (all 5 bits) to fill out the
Huffman codes, but the last two had better not show up in the data.
7. Unzip can check dynamic Huffman blocks for complete code sets.
The exception is that a single code would not be complete (see #4).
8. The five bits following the block type is really the number of
literal codes sent minus 257.
9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
(1+6+6). Therefore, to output three times the length, you output
three codes (1+1+1), whereas to output four times the same length,
you only need two codes (1+3). Hmm.
10. In the tree reconstruction algorithm, Code = Code + Increment
only if BitLength(i) is not zero. (Pretty obvious.)
11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
12. Note: length code 284 can represent 227-258, but length code 285
really is 258. The last length deserves its own, short code
since it gets used a lot in very redundant files. The length
258 is special since 258 - 3 (the min match length) is 255.
13. The literal/length and distance code bit lengths are read as a
single stream of lengths. It is possible (and advantageous) for
a repeat code (16, 17, or 18) to go across the boundary between
the two sets of lengths.
*/
struct inflate_blocks_state *inflate_blocks_new(z,wsize)
z_stream *z;
uInt wsize;
{
struct inflate_blocks_state *s;
if ((s = (struct inflate_blocks_state *)ZALLOC
(z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
return s;
if ((s->window = (Byte *)ZALLOC(z,1,wsize)) == Z_NULL)
{
ZFREE(z, s);
return Z_NULL;
}
s->mode = TYPE;
s->bitk = 0;
s->read = s->write = s->window;
s->end = s->window + wsize;
s->check = 1;
return s;
}
int inflate_blocks(s, z, r)
struct inflate_blocks_state *s;
z_stream *z;
int r;
{
uInt t; /* temporary storage */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
/* copy input/output information to locals (UPDATE macro restores) */
LOAD
/* process input based on current state */
while (1) switch (s->mode)
{
case TYPE:
NEEDBITS(3)
t = (uInt)b & 7;
s->last = t & 1;
switch (t >> 1)
{
case 0: /* stored */
DUMPBITS(3)
t = k & 7; /* go to byte boundary */
DUMPBITS(t)
s->mode = LENS; /* get length of stored block */
break;
case 1: /* fixed */
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_trees_fixed(&bl, &bd, &tl, &td);
s->sub.codes = inflate_codes_new(bl, bd, tl, td, z);
if (s->sub.codes == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
}
DUMPBITS(3)
s->mode = CODES;
break;
case 2: /* dynamic */
DUMPBITS(3)
s->mode = TABLE;
break;
case 3: /* illegal */
DUMPBITS(3)
s->mode = ERROR;
z->msg = "invalid block type";
r = Z_DATA_ERROR;
LEAVE
}
break;
case LENS:
NEEDBITS(32)
if ((~b) >> 16 != (b & 0xffff))
{
s->mode = ERROR;
z->msg = "invalid stored block lengths";
r = Z_DATA_ERROR;
LEAVE
}
k = 0; /* dump bits */
s->sub.left = (uInt)b & 0xffff;
s->mode = s->sub.left ? STORED : TYPE;
break;
case STORED:
do {
NEEDBYTE
NEEDOUT
OUTBYTE(NEXTBYTE)
} while (--s->sub.left);
s->mode = s->last ? DRY : TYPE;
break;
case TABLE:
NEEDBITS(14)
s->sub.trees.table = t = (uInt)b & 0x3fff;
#ifndef PKZIP_BUG_WORKAROUND
if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
{
s->mode = ERROR;
z->msg = "too many length or distance symbols";
r = Z_DATA_ERROR;
LEAVE
}
#endif
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
if (t < 19)
t = 19;
if ((s->sub.trees.blens = (uInt*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
DUMPBITS(14)
s->sub.trees.index = 0;
s->mode = BTREE;
case BTREE:
while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
{
NEEDBITS(3)
s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
DUMPBITS(3)
}
while (s->sub.trees.index < 19)
s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
s->sub.trees.bb = 7;
t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
&s->sub.trees.tb, z);
if (t != Z_OK)
{
r = t;
if (r == Z_DATA_ERROR)
s->mode = ERROR;
LEAVE
}
s->sub.trees.index = 0;
s->mode = DTREE;
case DTREE:
while (t = s->sub.trees.table,
s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
{
inflate_huft *h;
uInt i, j, c;
t = s->sub.trees.bb;
NEEDBITS(t)
h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
t = h->word.what.Bits;
c = h->more.Base;
if (c < 16)
{
DUMPBITS(t)
s->sub.trees.blens[s->sub.trees.index++] = c;
}
else /* c == 16..18 */
{
i = c == 18 ? 7 : c - 14;
j = c == 18 ? 11 : 3;
NEEDBITS(t + i)
DUMPBITS(t)
j += (uInt)b & inflate_mask[i];
DUMPBITS(i)
i = s->sub.trees.index;
t = s->sub.trees.table;
if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
(c == 16 && i < 1))
{
s->mode = ERROR;
z->msg = "invalid bit length repeat";
r = Z_DATA_ERROR;
LEAVE
}
c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
do {
s->sub.trees.blens[i++] = c;
} while (--j);
s->sub.trees.index = i;
}
}
inflate_trees_free(s->sub.trees.tb, z);
s->sub.trees.tb = Z_NULL;
{
uInt bl, bd;
inflate_huft *tl, *td;
struct inflate_codes_state *c;
bl = 9;
bd = 6;
t = s->sub.trees.table;
t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
s->sub.trees.blens, &bl, &bd, &tl, &td, z);
if (t != Z_OK)
{
if (t == (uInt)Z_DATA_ERROR)
s->mode = ERROR;
r = t;
LEAVE
}
if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
{
inflate_trees_free(td, z);
inflate_trees_free(tl, z);
r = Z_MEM_ERROR;
LEAVE
}
ZFREE(z, s->sub.trees.blens);
s->sub.codes = c;
}
s->mode = CODES;
case CODES:
UPDATE
if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
return inflate_flush(s, z, r);
r = Z_OK;
inflate_codes_free(s->sub.codes, z);
LOAD
s->mode = s->last ? DRY : TYPE;
break;
case DRY:
FLUSH
if (s->read != s->write)
LEAVE
s->mode = DONE;
case DONE:
r = Z_STREAM_END;
LEAVE
case ERROR:
r = Z_DATA_ERROR;
LEAVE
default:
r = Z_STREAM_ERROR;
LEAVE
}
}
int inflate_blocks_free(s, z, c, e)
struct inflate_blocks_state *s;
z_stream *z;
uLong *c;
int *e;
{
*e = s->bitk > 7 ? (s->bitb >> (s->bitk & 7)) & 0xff : -1;
*c = s->check;
if (s->mode == BTREE || s->mode == DTREE)
ZFREE(z, s->sub.trees.blens);
if (s->mode == CODES)
inflate_codes_free(s->sub.codes, z);
ZFREE(z, s->window);
ZFREE(z, s);
return Z_OK;
}

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/* infblock.h -- header to use infblock.c
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
struct inflate_blocks_state;
extern struct inflate_blocks_state * inflate_blocks_new __P((
z_stream *,
uInt)); /* window size */
extern int inflate_blocks __P((
struct inflate_blocks_state *,
z_stream *,
int)); /* initial return code */
extern int inflate_blocks_free __P((
struct inflate_blocks_state *,
z_stream *,
uLong *, /* check value on output */
int *)); /* possible leftover byte to return */

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/* infcodes.c -- process literals and length/distance pairs
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "inftrees.h"
#include "infutil.h"
#include "infcodes.h"
/* simplify the use of the inflate_huft type with some defines */
#define base more.Base
#define next more.Next
#define exop word.what.Exop
#define bits word.what.Bits
/* inflate codes private state */
struct inflate_codes_state {
/* mode */
enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
START, /* x: set up for LEN */
LEN, /* i: get length/literal/eob next */
LENEXT, /* i: getting length extra (have base) */
DIST, /* i: get distance next */
DISTEXT, /* i: getting distance extra */
COPY, /* o: copying bytes in window, waiting for space */
LIT, /* o: got literal, waiting for output space */
WASH, /* o: got eob, possibly still output waiting */
END, /* x: got eob and all data flushed */
BAD} /* x: got error */
mode; /* current inflate_codes mode */
/* mode dependent information */
uInt len;
union {
struct {
inflate_huft *tree; /* pointer into tree */
uInt need; /* bits needed */
} code; /* if LEN or DIST, where in tree */
uInt lit; /* if LIT, literal */
struct {
uInt get; /* bits to get for extra */
uInt dist; /* distance back to copy from */
} copy; /* if EXT or COPY, where and how much */
} sub; /* submode */
/* mode independent information */
Byte lbits; /* ltree bits decoded per branch */
Byte dbits; /* dtree bits decoder per branch */
inflate_huft *ltree; /* literal/length/eob tree */
inflate_huft *dtree; /* distance tree */
};
struct inflate_codes_state *inflate_codes_new(bl, bd, tl, td, z)
uInt bl, bd;
inflate_huft *tl, *td;
z_stream *z;
{
struct inflate_codes_state *c;
if ((c = (struct inflate_codes_state *)
ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
{
c->mode = START;
c->lbits = (Byte)bl;
c->dbits = (Byte)bd;
c->ltree = tl;
c->dtree = td;
}
return c;
}
int inflate_codes(s, z, r)
struct inflate_blocks_state *s;
z_stream *z;
int r;
{
uInt j; /* temporary storage */
inflate_huft *t; /* temporary pointer */
int e; /* extra bits or operation */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
Byte *f; /* pointer to copy strings from */
struct inflate_codes_state *c = s->sub.codes; /* codes state */
/* copy input/output information to locals (UPDATE macro restores) */
LOAD
/* process input and output based on current state */
while (1) switch (c->mode)
{ /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
case START: /* x: set up for LEN */
/* %%% check for avail in and out to do fast loop %%% */
c->sub.code.need = c->lbits;
c->sub.code.tree = c->ltree;
c->mode = LEN;
case LEN: /* i: get length/literal/eob next */
j = c->sub.code.need;
NEEDBITS(j)
t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
DUMPBITS(t->bits)
if ((e = (int)(t->exop)) < 0)
{
if (e == -128) /* invalid code */
{
c->mode = BAD;
z->msg = "invalid huffman code";
r = Z_DATA_ERROR;
LEAVE
}
e = -e;
if (e & 64) /* end of block */
{
c->mode = END;
break;
}
c->sub.code.need = e;
c->sub.code.tree = t->next;
break;
}
if (e & 16) /* literal */
{
c->sub.lit = t->base;
c->mode = LIT;
break;
}
c->sub.copy.get = e;
c->len = t->base;
c->mode = LENEXT;
case LENEXT: /* i: getting length extra (have base) */
j = c->sub.copy.get;
NEEDBITS(j)
c->len += (uInt)b & inflate_mask[j];
DUMPBITS(j)
c->sub.code.need = c->dbits;
c->sub.code.tree = c->dtree;
c->mode = DIST;
case DIST: /* i: get distance next */
j = c->sub.code.need;
NEEDBITS(j)
t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
DUMPBITS(t->bits)
if ((e = (int)(t->exop)) < 0)
{
if (e == -128)
{
c->mode = BAD;
z->msg = "invalid huffman code";
r = Z_DATA_ERROR;
LEAVE
}
c->sub.code.need = -e;
c->sub.code.tree = t->next;
break;
}
c->sub.copy.dist = t->base;
c->sub.copy.get = e;
c->mode = DISTEXT;
case DISTEXT: /* i: getting distance extra */
j = c->sub.copy.get;
NEEDBITS(j)
c->sub.copy.dist += (uInt)b & inflate_mask[j];
DUMPBITS(j)
c->mode = COPY;
case COPY: /* o: copying bytes in window, waiting for space */
f = q - s->window < c->sub.copy.dist ?
s->end - (c->sub.copy.dist - (q - s->window)) :
q - c->sub.copy.dist;
while (c->len)
{
NEEDOUT
OUTBYTE(*f++)
if (f == s->end)
f = s->window;
c->len--;
}
c->mode = START;
break;
case LIT: /* o: got literal, waiting for output space */
NEEDOUT
OUTBYTE(c->sub.lit)
c->mode = START;
break;
case WASH: /* o: got eob, possibly more output */
FLUSH
if (s->read != s->write)
LEAVE
c->mode = END;
case END:
r = Z_STREAM_END;
LEAVE
case BAD: /* x: got error */
r = Z_DATA_ERROR;
LEAVE
default:
r = Z_STREAM_ERROR;
LEAVE
}
}
void inflate_codes_free(c, z)
struct inflate_codes_state *c;
z_stream *z;
{
inflate_trees_free(c->dtree, z);
inflate_trees_free(c->ltree, z);
ZFREE(z, c);
}

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/* infcodes.h -- header to use infcodes.c
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
struct inflate_codes_state;
extern struct inflate_codes_state *inflate_codes_new __P((
uInt, uInt,
inflate_huft *, inflate_huft *,
z_stream *));
extern int inflate_codes __P((
struct inflate_blocks_state *,
z_stream *,
int));
extern void inflate_codes_free __P((
struct inflate_codes_state *,
z_stream *));

221
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/* inflate.c -- zlib interface to inflate modules
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "infblock.h"
struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
/* inflate private state */
struct internal_state {
/* mode */
enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
START, /* make new blocks state */
BLOCKS, /* decompressing blocks */
CHECK4, /* four check bytes to go */
CHECK3, /* three check bytes to go */
CHECK2, /* two check bytes to go */
CHECK1, /* one check byte to go */
DONE, /* finished check, done */
ERROR} /* got an error--stay here */
mode; /* current inflate mode */
int no_header;
uInt w_size; /* LZ77 window size (32K by default) */
uInt w_bits; /* log2(w_size) (8..16) */
/* mode dependent information */
union {
uInt method; /* if FLAGS, method byte */
struct inflate_blocks_state
*blocks; /* if BLOCKS, current state */
struct {
uLong was; /* computed check value */
uLong need; /* stream check value */
} check; /* if CHECK, check values to compare */
} sub; /* submode */
};
int inflateInit (strm)
z_stream *strm;
{
return inflateInit2(strm, WBITS);
}
int inflateInit2(z, windowBits)
z_stream *z;
int windowBits;
{
if (z == Z_NULL)
return Z_STREAM_ERROR;
if (z->zalloc == Z_NULL) z->zalloc = zcalloc;
if (z->zfree == Z_NULL) z->zfree = zcfree;
z->total_in = z->total_out = 0;
z->msg = Z_NULL;
if ((z->state = (struct internal_state *)
ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
return Z_MEM_ERROR;
z->state->mode = METHOD;
z->state->no_header = 0;
if (windowBits < 0) { /* undocumented feature: no zlib header */
windowBits = - windowBits;
z->state->no_header = 1;
z->state->sub.method = DEFLATED;
z->state->mode = START;
}
if (windowBits < 8 || windowBits > 15) {
inflateEnd(z);
return Z_STREAM_ERROR;
}
z->state->w_bits = windowBits;
z->state->w_size = 1<<windowBits;
return Z_OK;
}
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
int inflate(z, f)
z_stream *z;
int f;
{
int r;
uInt b;
uLong c;
if (z == Z_NULL || z->next_in == Z_NULL)
return Z_STREAM_ERROR;
r = Z_BUF_ERROR;
while (1) switch (z->state->mode)
{
case METHOD:
if (z->avail_in == 0) return r; r = Z_OK;
if (((z->state->sub.method = NEXTBYTE) & 0xf != DEFLATED))
{
z->state->mode = ERROR;
z->msg = "unknown compression method";
return Z_DATA_ERROR;
}
if ((z->state->sub.method >> 4) > z->state->w_bits)
{
z->state->mode = ERROR;
z->msg = "invalid window size";
return Z_DATA_ERROR;
}
z->state->mode = FLAG;
case FLAG:
if (z->avail_in == 0) return r; r = Z_OK;
if ((b = NEXTBYTE) & 0x20)
{
z->state->mode = ERROR;
z->msg = "invalid reserved bit";
return Z_DATA_ERROR;
}
if (((z->state->sub.method << 8) + b) % 31)
{
z->state->mode = ERROR;
z->msg = "incorrect header check";
return Z_DATA_ERROR;
}
z->state->mode = START;
case START:
if ((z->state->sub.blocks = inflate_blocks_new(z,z->state->w_size))
== Z_NULL)
return Z_MEM_ERROR;
z->state->mode = BLOCKS;
case BLOCKS:
if ((r = inflate_blocks(z->state->sub.blocks, z, r)) != Z_STREAM_END)
return r;
inflate_blocks_free(z->state->sub.blocks, z, &c, &r);
if (z->state->no_header) {
z->state->mode = DONE;
return Z_STREAM_END;
}
z->state->sub.check.was = c;
if (r != -1)
{
z->state->sub.check.need = (uLong)r << 24;
z->state->mode = CHECK3;
r = Z_OK;
break;
}
r = Z_OK;
z->state->mode = CHECK4;
case CHECK4:
if (z->avail_in == 0) return r; r = Z_OK;
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
z->state->mode = CHECK3;
case CHECK3:
if (z->avail_in == 0) return r; r = Z_OK;
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
z->state->mode = CHECK2;
case CHECK2:
if (z->avail_in == 0) return r; r = Z_OK;
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
z->state->mode = CHECK1;
case CHECK1:
if (z->avail_in == 0) return r; r = Z_OK;
z->state->sub.check.need += (uLong)NEXTBYTE;
if (z->state->sub.check.was != z->state->sub.check.need)
{
z->state->mode = ERROR;
z->msg = "incorrect data check";
return Z_DATA_ERROR;
}
z->state->mode = DONE;
case DONE:
return Z_STREAM_END;
case ERROR:
return Z_DATA_ERROR;
default:
return Z_STREAM_ERROR;
}
}
int inflateEnd(z)
z_stream *z;
{
uLong c;
int e;
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
return Z_STREAM_ERROR;
if (z->state->mode == BLOCKS)
inflate_blocks_free(z->state->sub.blocks, z, &c, &e);
ZFREE(z, z->state);
z->state = Z_NULL;
return Z_OK;
}
/* inflateSync not implemented yet--this just consumes input */
int inflateSync(z)
z_stream *z;
{
if (z == Z_NULL) return Z_STREAM_ERROR;
if (z->avail_in == 0) return Z_BUF_ERROR;
do {
z->total_in++;
} while (--z->avail_in);
return Z_DATA_ERROR;
}
/* inflateReset not fully implemented yet--this frees and reallocates */
int inflateReset(z)
z_stream *z;
{
int r;
if ((r = inflateEnd(z)) != Z_OK)
return r;
return inflateInit(z);
}

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/* temporary kludge assuming single pass decompression */
/* $Id: inflate.h,v 1.2 1995/04/11 14:47:32 jloup Exp $ */
#include <stdio.h>
#define NEXTBYTE \
(istrm->total_in++, istrm->avail_in-- == 0 ? \
(z_error("too small"), 0) : *istrm->next_in++)
#define FLUSH(n) { \
if (istrm->avail_out < n) z_error("too big"); \
istrm->avail_out -= n; \
memcpy(istrm->next_out, slide, n); \
istrm->next_out += n; \
istrm->total_out += n; \
}
#define WSIZE istrm->state->w_size
#define slide istrm->state->window
#define memzero(a,s) memset((a),0,(s))
#define inflate z_inflate
#define qflag 1

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inftest.c
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#include <stdio.h>
#include <stdlib.h>
#include "zutil.h"
/* This test is in honor of Ed Hamrick who suggested that the interface
to inflate be a byte at a time--this implements that, and is, of course,
monumentally slow. It has the virtue though of stressing the push-pull
interface for testing purposes. */
void main()
{
int a, r;
char c;
z_stream z;
z.zalloc = Z_NULL;
z.zfree = Z_NULL;
r = inflateInit(&z);
if (r != Z_OK)
fprintf(stderr, "init error: %s\n", z_errmsg[1 - r]);
while ((a = getchar()) != EOF)
{
/* feed one byte of input */
z.avail_out = 0;
c = (char)a;
z.next_in = (Byte*)&c;
z.avail_in = 1;
r = inflate(&z, 0);
if (r == Z_STREAM_END)
break;
if (r != Z_OK)
{
fprintf(stderr, "inflate error: %s\n", z_errmsg[1 - r]);
break;
}
if (z.avail_in != 0)
{
fprintf(stderr, "inflate didn't eat byte and didn't say buf err!\n");
break;
}
/* empty output one byte at a time */
while (1)
{
z.next_out = (Byte*)&c;
z.avail_out = 1;
r = inflate(&z, 0);
if (r == Z_STREAM_END)
break;
if (r != Z_OK && r != Z_BUF_ERROR)
{
fprintf(stderr, "inflate error: %s\n", z_errmsg[1 - r]);
break;
}
if (z.avail_out == 0)
putchar(c);
else
break;
}
if (r != Z_OK && r != Z_BUF_ERROR)
break;
}
inflateEnd(&z);
fprintf(stderr, "%d bytes in, %d bytes out\n", z.total_in, z.total_out);
if (z.msg != NULL)
fprintf(stderr, "msg is <%s>\n", z.msg);
}

471
inftrees.c
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/* inftrees.c -- generate Huffman trees for efficient decoding
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "inftrees.h"
struct internal_state {int dummy;}; /* for buggy compilers */
/* simplify the use of the inflate_huft type with some defines */
#define base more.Base
#define next more.Next
#define exop word.what.Exop
#define bits word.what.Bits
local int huft_build __P((
uInt *, /* code lengths in bits */
uInt, /* number of codes */
uInt, /* number of "simple" codes */
uInt *, /* list of base values for non-simple codes */
uInt *, /* list of extra bits for non-simple codes */
inflate_huft **, /* result: starting table */
uInt *, /* maximum lookup bits (returns actual) */
z_stream *)); /* for zalloc function */
local voidp falloc __P((
voidp, /* opaque pointer (not used) */
uInt, /* number of items */
uInt)); /* size of item */
local void ffree __P((
voidp q, /* opaque pointer (not used) */
voidp p)); /* what to free (not used) */
/* Tables for deflate from PKZIP's appnote.txt. */
local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
/* actually lengths - 2; also see note #13 above about 258 */
local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 128, 128}; /* 128==invalid */
local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
8193, 12289, 16385, 24577};
local uInt cpdext[] = { /* Extra bits for distance codes */
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
12, 12, 13, 13};
/*
Huffman code decoding is performed using a multi-level table lookup.
The fastest way to decode is to simply build a lookup table whose
size is determined by the longest code. However, the time it takes
to build this table can also be a factor if the data being decoded
is not very long. The most common codes are necessarily the
shortest codes, so those codes dominate the decoding time, and hence
the speed. The idea is you can have a shorter table that decodes the
shorter, more probable codes, and then point to subsidiary tables for
the longer codes. The time it costs to decode the longer codes is
then traded against the time it takes to make longer tables.
This results of this trade are in the variables lbits and dbits
below. lbits is the number of bits the first level table for literal/
length codes can decode in one step, and dbits is the same thing for
the distance codes. Subsequent tables are also less than or equal to
those sizes. These values may be adjusted either when all of the
codes are shorter than that, in which case the longest code length in
bits is used, or when the shortest code is *longer* than the requested
table size, in which case the length of the shortest code in bits is
used.
There are two different values for the two tables, since they code a
different number of possibilities each. The literal/length table
codes 286 possible values, or in a flat code, a little over eight
bits. The distance table codes 30 possible values, or a little less
than five bits, flat. The optimum values for speed end up being
about one bit more than those, so lbits is 8+1 and dbits is 5+1.
The optimum values may differ though from machine to machine, and
possibly even between compilers. Your mileage may vary.
*/
/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
#define BMAX 15 /* maximum bit length of any code */
#define N_MAX 288 /* maximum number of codes in any set */
#ifdef DEBUG
uInt inflate_hufts;
#endif
local int huft_build(b, n, s, d, e, t, m, zs)
uInt *b; /* code lengths in bits (all assumed <= BMAX) */
uInt n; /* number of codes (assumed <= N_MAX) */
uInt s; /* number of simple-valued codes (0..s-1) */
uInt *d; /* list of base values for non-simple codes */
uInt *e; /* list of extra bits for non-simple codes */
inflate_huft **t; /* result: starting table */
uInt *m; /* maximum lookup bits, returns actual */
z_stream *zs; /* for zalloc function */
/* Given a list of code lengths and a maximum table size, make a set of
tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
if the given code set is incomplete (the tables are still built in this
case), Z_DATA_ERROR if the input is invalid (all zero length codes or an
over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */
{
uInt a; /* counter for codes of length k */
uInt c[BMAX+1]; /* bit length count table */
uInt f; /* i repeats in table every f entries */
int g; /* maximum code length */
int h; /* table level */
register uInt i; /* counter, current code */
register uInt j; /* counter */
register int k; /* number of bits in current code */
int l; /* bits per table (returned in m) */
register uInt *p; /* pointer into c[], b[], or v[] */
register inflate_huft *q; /* points to current table */
inflate_huft r; /* table entry for structure assignment */
inflate_huft *u[BMAX]; /* table stack */
uInt v[N_MAX]; /* values in order of bit length */
register int w; /* bits before this table == (l * h) */
uInt x[BMAX+1]; /* bit offsets, then code stack */
uInt *xp; /* pointer into x */
int y; /* number of dummy codes added */
uInt z; /* number of entries in current table */
/* Generate counts for each bit length */
p = c;
#define C0 *p++ = 0;
#define C2 C0 C0 C0 C0
#define C4 C2 C2 C2 C2
C4 /* clear c[]--assume BMAX+1 is 16 */
p = b; i = n;
do {
c[*p++]++; /* assume all entries <= BMAX */
} while (--i);
if (c[0] == n) /* null input--all zero length codes */
{
*t = (inflate_huft *)Z_NULL;
*m = 0;
return Z_OK;
}
/* Find minimum and maximum length, bound *m by those */
l = *m;
for (j = 1; j <= BMAX; j++)
if (c[j])
break;
k = j; /* minimum code length */
if ((uInt)l < j)
l = j;
for (i = BMAX; i; i--)
if (c[i])
break;
g = i; /* maximum code length */
if ((uInt)l > i)
l = i;
*m = l;
/* Adjust last length count to fill out codes, if needed */
for (y = 1 << j; j < i; j++, y <<= 1)
if ((y -= c[j]) < 0)
return Z_DATA_ERROR;
if ((y -= c[i]) < 0)
return Z_DATA_ERROR;
c[i] += y;
/* Generate starting offsets into the value table for each length */
x[1] = j = 0;
p = c + 1; xp = x + 2;
while (--i) { /* note that i == g from above */
*xp++ = (j += *p++);
}
/* Make a table of values in order of bit lengths */
p = b; i = 0;
do {
if ((j = *p++) != 0)
v[x[j]++] = i;
} while (++i < n);
/* Generate the Huffman codes and for each, make the table entries */
x[0] = i = 0; /* first Huffman code is zero */
p = v; /* grab values in bit order */
h = -1; /* no tables yet--level -1 */
w = -l; /* bits decoded == (l * h) */
u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
q = (inflate_huft *)Z_NULL; /* ditto */
z = 0; /* ditto */
/* go through the bit lengths (k already is bits in shortest code) */
for (; k <= g; k++)
{
a = c[k];
while (a--)
{
/* here i is the Huffman code of length k bits for value *p */
/* make tables up to required level */
while (k > w + l)
{
h++;
w += l; /* previous table always l bits */
/* compute minimum size table less than or equal to l bits */
z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */
if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
{ /* too few codes for k-w bit table */
f -= a + 1; /* deduct codes from patterns left */
xp = c + k;
if (j < z)
while (++j < z) /* try smaller tables up to z bits */
{
if ((f <<= 1) <= *++xp)
break; /* enough codes to use up j bits */
f -= *xp; /* else deduct codes from patterns */
}
}
z = 1 << j; /* table entries for j-bit table */
/* allocate and link in new table */
if ((q = (inflate_huft *)ZALLOC
(zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
{
if (h)
inflate_trees_free(u[0], zs);
return Z_MEM_ERROR; /* not enough memory */
}
#ifdef DEBUG
inflate_hufts += z + 1;
#endif
*t = q + 1; /* link to list for huft_free() */
*(t = &(q->next)) = (inflate_huft *)Z_NULL;
u[h] = ++q; /* table starts after link */
/* connect to last table, if there is one */
if (h)
{
x[h] = i; /* save pattern for backing up */
r.bits = (char)l; /* bits to dump before this table */
r.exop = (char)(-j); /* bits in this table */
r.next = q; /* pointer to this table */
j = i >> (w - l); /* (get around Turbo C bug) */
u[h-1][j] = r; /* connect to last table */
}
}
/* set up table entry in r */
r.bits = (char)(k - w);
if (p >= v + n)
r.exop = -128; /* out of values--invalid code */
else if (*p < s)
{
r.exop = (char)(*p < 256 ? 16 : -64); /* 256 is end-of-block code */
r.base = *p++; /* simple code is just the value */
}
else
{
r.exop = (char)e[*p - s]; /* non-simple--look up in lists */
r.base = d[*p++ - s];
}
/* fill code-like entries with r */
f = 1 << (k - w);
for (j = i >> w; j < z; j += f)
q[j] = r;
/* backwards increment the k-bit code i */
for (j = 1 << (k - 1); i & j; j >>= 1)
i ^= j;
i ^= j;
/* backup over finished tables */
while ((i & ((1 << w) - 1)) != x[h])
{
h--; /* don't need to update q */
w -= l;
}
}
}
/* Return Z_BUF_ERROR if we were given an incomplete table */
return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
}
int inflate_trees_bits(c, bb, tb, z)
uInt *c; /* 19 code lengths */
uInt *bb; /* bits tree desired/actual depth */
inflate_huft **tb; /* bits tree result */
z_stream *z; /* for zfree function */
{
int r;
r = huft_build(c, 19, 19, (uInt*)Z_NULL, (uInt*)Z_NULL, tb, bb, z);
if (r == Z_DATA_ERROR)
z->msg = "oversubscribed dynamic bit lengths tree";
else if (r == Z_BUF_ERROR)
{
inflate_trees_free(*tb, z);
z->msg = "incomplete dynamic bit lengths tree";
r = Z_DATA_ERROR;
}
return r;
}
int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
uInt nl; /* number of literal/length codes */
uInt nd; /* number of distance codes */
uInt *c; /* that many (total) code lengths */
uInt *bl; /* literal desired/actual bit depth */
uInt *bd; /* distance desired/actual bit depth */
inflate_huft **tl; /* literal/length tree result */
inflate_huft **td; /* distance tree result */
z_stream *z; /* for zfree function */
{
int r;
/* build literal/length tree */
if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
{
if (r == Z_DATA_ERROR)
z->msg = "oversubscribed literal/length tree";
else if (r == Z_BUF_ERROR)
{
inflate_trees_free(*tl, z);
z->msg = "incomplete literal/length tree";
r = Z_DATA_ERROR;
}
return r;
}
/* build distance tree */
if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
{
if (r == Z_DATA_ERROR)
z->msg = "oversubscribed literal/length tree";
else if (r == Z_BUF_ERROR) {
#ifdef PKZIP_BUG_WORKAROUND
r = Z_OK;
}
#else
inflate_trees_free(*td, z);
z->msg = "incomplete literal/length tree";
r = Z_DATA_ERROR;
}
inflate_trees_free(*tl, z);
return r;
#endif
}
/* done */
return Z_OK;
}
/* build fixed tables only once--keep them here */
local int fixed_lock = 0;
local int fixed_built = 0;
#define FIXEDH 530 /* number of hufts used by fixed tables */
local uInt fixed_left = FIXEDH;
local inflate_huft fixed_mem[FIXEDH];
local uInt fixed_bl;
local uInt fixed_bd;
local inflate_huft *fixed_tl;
local inflate_huft *fixed_td;
local voidp falloc(q, n, s)
voidp q; /* opaque pointer (not used) */
uInt n; /* number of items */
uInt s; /* size of item */
{
Assert(s == sizeof(inflate_huft) && n <= fixed_left,
"inflate_trees falloc overflow");
fixed_left -= n;
return (voidp)(fixed_mem + fixed_left);
}
local void ffree(q, p)
voidp q;
voidp p;
{
Assert(0, "inflate_trees ffree called!");
}
int inflate_trees_fixed(bl, bd, tl, td)
uInt *bl; /* literal desired/actual bit depth */
uInt *bd; /* distance desired/actual bit depth */
inflate_huft **tl; /* literal/length tree result */
inflate_huft **td; /* distance tree result */
{
/* build fixed tables if not built already--lock out other instances */
while (++fixed_lock > 1)
fixed_lock--;
if (!fixed_built)
{
int k; /* temporary variable */
unsigned c[288]; /* length list for huft_build */
z_stream z; /* for falloc function */
/* set up fake z_stream for memory routines */
z.zalloc = falloc;
z.zfree = ffree;
z.opaque = Z_NULL;
/* literal table */
for (k = 0; k < 144; k++)
c[k] = 8;
for (; k < 256; k++)
c[k] = 9;
for (; k < 280; k++)
c[k] = 7;
for (; k < 288; k++)
c[k] = 8;
fixed_bl = 7;
huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
/* distance table */
for (k = 0; k < 30; k++)
c[k] = 5;
fixed_bd = 5;
huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
/* done */
fixed_built = 1;
}
fixed_lock--;
*bl = fixed_bl;
*bd = fixed_bd;
*tl = fixed_tl;
*td = fixed_td;
return Z_OK;
}
int inflate_trees_free(t, z)
inflate_huft *t; /* table to free */
z_stream *z; /* for zfree function */
/* Free the malloc'ed tables built by huft_build(), which makes a linked
list of the tables it made, with the links in a dummy first entry of
each table. */
{
register inflate_huft *p, *q;
/* Don't free fixed trees */
if (t >= fixed_mem && t <= fixed_mem + FIXEDH)
return Z_OK;
/* Go through linked list, freeing from the malloced (t[-1]) address. */
p = t;
while (p != Z_NULL)
{
q = (--p)->next;
ZFREE(z,p);
p = q;
}
return Z_OK;
}

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/* inftrees.h -- header to use inftrees.c
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
/* Huffman code lookup table entry--this entry is four bytes for machines
that have 16-bit pointers (e.g. PC's in the small or medium model).
Valid extra bits (exop) are 0..13. exop == -64 is EOB (end of block),
exop == 16 means that v is a literal, exop < 0 means that v is a pointer
to the next table, which codes -exop bits, and lastly exop == -128
indicates an unused code. If a code with exop == -128 is looked up,
this implies an error in the data. */
typedef struct inflate_huft_s inflate_huft;
struct inflate_huft_s {
union {
struct {
char Exop; /* number of extra bits or operation */
char Bits; /* number of bits in this code or subcode */
} what;
Byte *pad; /* pad structure to a power of 2 (4 bytes for */
} word; /* 16-bit, 8 bytes for 32-bit machines) */
union {
uInt Base; /* literal, length base, or distance base */
inflate_huft *Next; /* pointer to next level of table */
} more;
};
#ifdef DEBUG
extern uInt inflate_hufts;
#endif
extern int inflate_trees_bits __P((
uInt *, /* 19 code lengths */
uInt *, /* bits tree desired/actual depth */
inflate_huft **, /* bits tree result */
z_stream *)); /* for zalloc, zfree functions */
extern int inflate_trees_dynamic __P((
uInt, /* number of literal/length codes */
uInt, /* number of distance codes */
uInt *, /* that many (total) code lengths */
uInt *, /* literal desired/actual bit depth */
uInt *, /* distance desired/actual bit depth */
inflate_huft **, /* literal/length tree result */
inflate_huft **, /* distance tree result */
z_stream *)); /* for zalloc, zfree functions */
extern int inflate_trees_fixed __P((
uInt *, /* literal desired/actual bit depth */
uInt *, /* distance desired/actual bit depth */
inflate_huft **, /* literal/length tree result */
inflate_huft **)); /* distance tree result */
extern int inflate_trees_free __P((
inflate_huft *, /* tables to free */
z_stream *)); /* for zfree function */

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/* inflate_util.c -- data and routines common to blocks and codes
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "inftrees.h"
#include "infutil.h"
struct inflate_codes_state {int dummy;}; /* for buggy compilers */
/* And'ing with mask[n] masks the lower n bits */
uInt inflate_mask[] = {
0x0000,
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
/* copy as much as possible from the sliding window to the output area */
int inflate_flush(s, z, r)
struct inflate_blocks_state *s;
z_stream *z;
int r;
{
uInt n;
Byte *p, *q;
/* local copies of source and destination pointers */
p = z->next_out;
q = s->read;
/* compute number of bytes to copy as far as end of window */
n = (q <= s->write ? s->write : s->end) - q;
if (n > z->avail_out) n = z->avail_out;
if (n && r == Z_BUF_ERROR) r = Z_OK;
/* update counters */
z->avail_out -= n;
z->total_out += n;
/* update check information */
s->check = adler32(s->check, q, n);
/* copy as far as end of window */
while (n--) *p++ = *q++;
/* see if more to copy at beginning of window */
if (q == s->end)
{
/* wrap source pointer */
q = s->window;
/* compute bytes to copy */
n = s->write - q;
if (n > z->avail_out) n = z->avail_out;
if (n && r == Z_BUF_ERROR) r = Z_OK;
/* update counters */
z->avail_out -= n;
z->total_out += n;
/* update check information */
s->check = adler32(s->check, q, n);
/* copy */
while (n--) *p++ = *q++;
}
/* update pointers */
z->next_out = p;
s->read = q;
/* done */
return r;
}

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/* infutil.h -- types and macros common to blocks and codes
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
/* inflate blocks semi-private state */
struct inflate_blocks_state {
/* mode */
enum {
TYPE, /* get type bits (3, including end bit) */
LENS, /* get lengths for stored */
STORED, /* processing stored block */
TABLE, /* get table lengths */
BTREE, /* get bit lengths tree for a dynamic block */
DTREE, /* get length, distance trees for a dynamic block */
CODES, /* processing fixed or dynamic block */
DRY, /* output remaining window bytes */
DONE, /* finished last block, done */
ERROR} /* got a data error--stuck here */
mode; /* current inflate_block mode */
/* mode dependent information */
union {
uInt left; /* if STORED, bytes left to copy */
struct {
uInt table; /* table lengths (14 bits) */
uInt index; /* index into blens (or border) */
uInt *blens; /* bit lengths of codes */
uInt bb; /* bit length tree depth */
inflate_huft *tb; /* bit length decoding tree */
} trees; /* if DTREE, decoding info for trees */
struct inflate_codes_state
*codes; /* if CODES, current state */
} sub; /* submode */
uInt last; /* true if this block is the last block */
/* mode independent information */
uInt bitk; /* bits in bit buffer */
uLong bitb; /* bit buffer */
Byte *window; /* sliding window */
Byte *end; /* one byte after sliding window */
Byte *read; /* window read pointer */
Byte *write; /* window write pointer */
uLong check; /* check on output */
};
/* defines for inflate input/output */
/* update pointers and return */
#define UPDBITS {s->bitb=b;s->bitk=k;}
#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
#define UPDOUT {s->write=q;}
#define UPDATE {UPDBITS UPDIN UPDOUT}
#define LEAVE {UPDATE return inflate_flush(s,z,r);}
/* get bytes and bits */
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
#define NEXTBYTE (n--,*p++)
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define DUMPBITS(j) {b>>=(j);k-=(j);}
/* output bytes */
#define WAVAIL (q<s->read?s->read-q-1:s->end-q)
#define LOADOUT {q=s->write;m=WAVAIL;}
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
/* load local pointers */
#define LOAD {LOADIN LOADOUT}
/* masks for lower bits */
extern uInt inflate_mask[];
/* copy as much as possible from the sliding window to the output area */
extern int inflate_flush __P((
struct inflate_blocks_state *,
z_stream *,
int));
struct internal_state {int dummy;}; /* for buggy compilers */

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/* minigzip.c -- simulate gzip using the zlib compression library
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/*
* minigzip is a minimal implementation of the gzip utility. This is
* only an example of using zlib and isn't meant to replace the
* full-featured gzip. No attempt is made to deal with file systems
* limiting names to 14 or 8+3 characters, etc... Error checking is
* very limited. So use minigzip only for testing; use gzip for the
* real thing. On MSDOS, use only on file names without extension
* or in pipe mode.
*/
/* $Id: minigzip.c,v 1.1 1995/04/14 13:35:59 jloup Exp $ */
#include <stdio.h>
#include "zlib.h"
#ifdef MSDOS
# include <fcntl.h>
# define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
#else
# define SET_BINARY_MODE(file)
#endif
#define BUFLEN 4096
#define MAX_NAME_LEN 1024
#define local static
/* For MSDOS and other systems with limitation on stack size. For Unix,
#define local
works also.
*/
char *prog;
/* ===========================================================================
* Display error message and exit
*/
void error(msg)
char *msg;
{
fprintf(stderr, "%s: %s\n", prog, msg);
exit(1);
}
/* ===========================================================================
* Compress input to output then close both files.
*/
void gz_compress(in, out)
FILE *in;
gzFile out;
{
local char buf[BUFLEN];
int len;
int err;
for (;;) {
len = fread(buf, 1, sizeof(buf), in);
if (ferror(in)) {
perror("fread");
exit(1);
}
if (len == 0) break;
if (gzwrite(out, buf, len) != len) error(gzerror(out, &err));
}
fclose(in);
if (gzclose(out) != Z_OK) error("failed gzclose");
}
/* ===========================================================================
* Uncompress input to output then close both files.
*/
void gz_uncompress(in, out)
gzFile in;
FILE *out;
{
local char buf[BUFLEN];
int len;
int err;
for (;;) {
len = gzread(in, buf, sizeof(buf));
if (len < 0) error (gzerror(in, &err));
if (len == 0) break;
if (fwrite(buf, 1, len, out) != len) error("failed fwrite");
}
if (fclose(out)) error("failed fclose");
if (gzclose(in) != Z_OK) error("failed gzclose");
}
/* ===========================================================================
* Compress the given file: create a corresponding .gz file and remove the
* original.
*/
void file_compress(file)
char *file;
{
local char outfile[MAX_NAME_LEN];
FILE *in;
gzFile out;
strcpy(outfile, file);
strcat(outfile, ".gz");
in = fopen(file, "rb");
if (in == NULL) {
perror(file);
exit(1);
}
out = gzopen(outfile, "wb");
if (out == NULL) {
fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
exit(1);
}
gz_compress(in, out);
unlink(file);
}
/* ===========================================================================
* Uncompress the given file and remove the original.
*/
void file_uncompress(file)
char *file;
{
local char buf[MAX_NAME_LEN];
char *infile, *outfile;
FILE *out;
gzFile in;
int len = strlen(file);
strcpy(buf, file);
if (len > 3 && strcmp(file+len-3, ".gz") == 0) {
infile = file;
outfile = buf;
outfile[len-3] = '\0';
} else {
outfile = file;
infile = buf;
strcat(infile, ".gz");
}
in = gzopen(infile, "rb");
if (in == NULL) {
fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
exit(1);
}
out = fopen(outfile, "wb");
if (out == NULL) {
perror(file);
exit(1);
}
gz_uncompress(in, out);
unlink(infile);
}
/* ===========================================================================
* Usage: minigzip [-d] [files...]
*/
void main(argc, argv)
int argc;
char *argv[];
{
int uncompr = 0;
gzFile file;
prog = argv[0];
argc--, argv++;
if (argc > 0) {
uncompr = (strcmp(*argv, "-d") == 0);
if (uncompr) {
argc--, argv++;
}
}
if (argc == 0) {
SET_BINARY_MODE(stdin);
SET_BINARY_MODE(stdout);
if (uncompr) {
file = gzdopen(fileno(stdin), "rb");
if (file == NULL) error("can't gzdopen stdin");
gz_uncompress(file, stdout);
} else {
file = gzdopen(fileno(stdout), "wb");
if (file == NULL) error("can't gzdopen stdout");
gz_compress(stdin, file);
}
} else {
do {
if (uncompr) {
file_uncompress(*argv);
} else {
file_compress(*argv);
}
} while (argv++, --argc);
}
exit(0);
}

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/* uncompr.c -- decompress a memory buffer
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: uncompr.c,v 1.4 1995/04/10 16:22:22 jloup Exp $ */
#include "zlib.h"
/* ===========================================================================
Decompresses the source buffer into the destination buffer. sourceLen is
the byte length of the source buffer. Upon entry, destLen is the total
size of the destination buffer, which must be large enough to hold the
entire uncompressed data. (The size of the uncompressed data must have
been saved previously by the compressor and transmitted to the decompressor
by some mechanism outside the scope of this compression library.)
Upon exit, destLen is the actual size of the compressed buffer.
This function can be used to decompress a whole file at once if the
input file is mmap'ed.
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_BUF_ERROR if there was not enough room in the output
buffer, or Z_DATA_ERROR if the input data was corrupted.
*/
int uncompress (dest, destLen, source, sourceLen)
Byte *dest;
uLong *destLen;
Byte *source;
uLong sourceLen;
{
z_stream stream;
int err;
stream.next_in = source;
stream.avail_in = (uInt)sourceLen;
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
stream.next_out = dest;
stream.avail_out = (uInt)*destLen;
if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
stream.zalloc = (alloc_func)0;
stream.zfree = (free_func)0;
err = inflateInit(&stream);
if (err != Z_OK) return err;
err = inflate(&stream, Z_FINISH);
if (err != Z_STREAM_END) {
inflateEnd(&stream);
return err;
}
*destLen = stream.total_out;
err = inflateEnd(&stream);
return err;
}

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/* zconf.h -- configuration of the zlib compression library
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: zconf.h,v 1.7 1995/04/12 20:42:28 jloup Exp $ */
#ifndef _ZCONF_H
#define _ZCONF_H
/*
The library does not install any signal handler. It is recommended to
add at least a handler for SIGSEGV when decompressing; the library checks
the consistency of the input data whenever possible but may go nuts
for some forms of corrupted input.
*/
/*
* Compile with -DMAXSEG_64K if the alloc function cannot allocate more
* than 64k bytes at a time (needed on systems with 16-bit int).
*/
#if defined(_GNUC__) && !defined(__32BIT__)
# define __32BIT__
#endif
#if defined(__MSDOS__) && !defined(MSDOS)
# define MSDOS
#endif
#if defined(MSDOS) && !defined(__32BIT__)
# define MAXSEG_64K
#endif
#ifdef MAXSEG_64K
# define MAX_MEM_LEVEL 8
#else
# define MAX_MEM_LEVEL 9
#endif
/* Type declarations */
#ifndef __P /* function prototypes */
# if defined(__STDC__) || defined(MSDOS)
# define __P(args) args
# else
# define __P(args) ()
# endif
#endif
#ifndef Byte
typedef unsigned char Byte; /* 8 bits */
#endif
#ifndef uInt
typedef unsigned int uInt; /* may be 16 or 32 bits */
#endif
#ifndef uLong
typedef unsigned long uLong; /* 32 bits or more */
#endif
#ifndef voidp
# if defined(__STDC__) || defined(MSDOS)
typedef void *voidp;
# else
typedef Byte *voidp;
# endif
#endif
#endif /* _ZCONF_H */

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/* zlib.h -- interface of the 'zlib' general purpose compression library
version 0.7 April 14th, 1995.
Copyright (C) 1995 Jean-loup Gailly and Mark Adler
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
Jean-loup Gailly Mark Adler
gzip@prep.ai.mit.edu madler@cco.caltech.edu
*/
#ifndef _ZLIB_H
#define _ZLIB_H
#include "zconf.h"
#define ZLIB_VERSION "0.7"
/*
The 'zlib' compression library provides in-memory compression and
decompression functions, including integrity checks of the uncompressed
data. This version of the library supports only one compression method
(deflation) but other algorithms may be added later and will have the same
stream interface.
For compression the application must provide the output buffer and
may optionally provide the input buffer for optimization. For decompression,
the application must provide the input buffer and may optionally provide
the output buffer for optimization.
Compression can be done in a single step if the buffers are large
enough (for example if an input file is mmap'ed), or can be done by
repeated calls of the compression function. In the latter case, the
application must provide more input and/or consume the output
(providing more output space) before each call.
*/
typedef voidp (*alloc_func) __P((voidp opaque, uInt items, uInt size));
typedef void (*free_func) __P((voidp opaque, voidp address));
struct internal_state;
typedef struct z_stream_s {
Byte *next_in; /* next input byte */
uInt avail_in; /* number of bytes available at next_in */
uLong total_in; /* total nb of input bytes read so far */
Byte *next_out; /* next output byte should be put there */
uInt avail_out; /* remaining free space at next_out */
uLong total_out; /* total nb of bytes output so far */
char *msg; /* last error message, NULL if no error */
struct internal_state *state; /* not visible by applications */
alloc_func zalloc; /* used to allocate the internal state */
free_func zfree; /* used to free the internal state */
voidp opaque; /* private data object passed to zalloc and zfree */
Byte data_type; /* best guess about the data type: ascii or binary */
} z_stream;
/*
The application must update next_in and avail_in when avail_in has
dropped to zero. It must update next_out and avail_out when avail_out
has dropped to zero. The application must initialize zalloc, zfree and
opaque before calling the init function. All other fields are set by the
compression library and must not be updated by the application.
The opaque value provided by the application will be passed as first
parameter for calls of zalloc and zfree. This can be useful for custom
memory management. The compression library attaches no meaning to the
opaque value.
zalloc must return Z_NULL if there is not enough memory for the object.
On 16-bit systems, the functions zalloc and zfree must be able to allocate
exactly 65536 bytes, but will not be require to allocate more than this
if the symbol MAXSEG_64K is defined (see zconf.h).
The fields total_in and total_out can be used for statistics or
progress reports. After compression, total_in holds the total size of
the uncompressed data and may be saved for use in the decompressor
(particularly if the decompressor wants to decompress everything in
a single step).
*/
/* constants */
#define Z_NO_FLUSH 0
#define Z_PARTIAL_FLUSH 1
#define Z_FULL_FLUSH 2
#define Z_FINISH 4
/* See deflate() below for the usage of these constants */
#define Z_OK 0
#define Z_STREAM_END 1
#define Z_ERRNO (-1)
#define Z_STREAM_ERROR (-2)
#define Z_DATA_ERROR (-3)
#define Z_MEM_ERROR (-4)
#define Z_BUF_ERROR (-5)
/* error codes for the compression/decompression functions */
#define Z_BEST_SPEED 1
#define Z_BEST_COMPRESSION 9
#define Z_DEFAULT_COMPRESSION (-1)
/* compression levels */
#define Z_FILTERED 1
#define Z_HUFFMAN_ONLY 2
#define Z_DEFAULT_STRATEGY 0
#define Z_BINARY 0
#define Z_ASCII 1
#define Z_UNKNOWN 2
/* Used to set the data_type field */
#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
extern char *zlib_version;
/* The application can compare zlib_version and ZLIB_VERSION for consistency.
If the first character differs, the library code actually used is
not compatible with the zlib.h header file used by the application.
*/
/* basic functions */
extern int deflateInit __P((z_stream *strm, int level));
/*
Initializes the internal stream state for compression. The fields
zalloc, zfree and opaque must be initialized before by the caller.
If zalloc and zfree are set to Z_NULL, deflateInit updates them to
use default allocation functions.
The compression level must be Z_DEFAULT_COMPRESSION, or between 1 and 9:
1 gives best speed, 9 gives best compression. Z_DEFAULT_COMPRESSION requests
a default compromise between speed and compression (currently equivalent
to level 6).
deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_STREAM_ERROR if the stream state was inconsistent (such
as zalloc being NULL). msg is set to null if there is no error message.
deflateInit does not perform any compression: this will be done by
deflate(). */
extern int deflate __P((z_stream *strm, int flush));
/*
Performs one or both of the following actions:
- Compress more input starting at next_in and update next_in and avail_in
accordingly. If not all input can be processed (because there is not
enough room in the output buffer), next_in is updated and processing
will resume at this point for the next call of deflate().
- Provide more output starting at next_out and update next_out and avail_out
accordingly. This action is forced if the parameter flush is non zero.
Forcing flush frequently degrades the compression ratio, so this parameter
should be set only when necessary (in interactive applications).
Some output may be provided even if flush is not set.
Before the call of deflate(), the application should ensure that at least
one of the actions is possible, by providing more input and/or consuming
more output, and updating avail_in or avail_out accordingly.
The application can consume the compressed output when the output
buffer is full (avail_out == 0), or after each call of deflate().
If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
block is byte aligned and flushed to the output buffer so that the
decompressor can get all input data available so far; if the compression
method is 8 (deflate without partial flush capability), the current block
is terminated. If flush is set to Z_FULL_FLUSH, the compression block is
terminated, a special marker is output and the compression dictionary is
discarded; this is useful to allow the decompressor to synchronize if one
compressed block has been damaged.
Flushing degrades compression and so should be used only when necessary.
Using Z_FULL_FLUSH too often can seriously degrade the compression.
If the parameter flush is set to Z_FINISH, all pending input is
processed and all pending output is flushed. The next operation on this
stream must be another call of deflate with Z_FINISH but no more input data
(unchanged avail_in) if this call returned with avail_out equal to zero,
or a call of deflateEnd to deallocate the compression state. Z_FINISH can
be used immediately after deflateInit if all the compression is to be
done in a single step. In this case, avail_out must be at least 0.1%
larger than avail_in plus 8 bytes.
deflate() may update strm->data_type if it can make a good guess about
the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
binary. This field is only for information purposes and does not affect
the compression algorithm in any manner.
deflate() return Z_OK if some progress has been made (more input processed
or more output produced), Z_STREAM_ERROR if the stream state was
inconsistent (for example if next_in or next_out was NULL), Z_BUF_ERROR if
no progress is possible or if there was not enough room in the output buffer
when Z_FINISH is used.
*/
extern int deflateEnd __P((z_stream *strm));
/*
All dynamically allocated data structures for this stream are freed.
This function discards any unprocessed input and does not flush any
pending output.
deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
stream state was inconsistent. In the error case, msg may be set
but then points to a static string (which must not be deallocated).
*/
extern int inflateInit __P((z_stream *strm));
/*
Initializes the internal stream state for decompression. The fields
zalloc and zfree must be initialized before by the caller. If zalloc and
zfree are set to Z_NULL, deflateInit updates them to use default allocation
functions.
inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_STREAM_ERROR if the stream state was inconsistent (such
as zalloc being NULL). msg is set to null if there is no error message.
inflateInit does not perform any decompression: this will be done by
inflate().
*/
extern int inflate __P((z_stream *strm, int flush));
/*
Performs one or both of the following actions:
- Decompress more input starting at next_in and update next_in and avail_in
accordingly. If not all input can be processed (because there is not
enough room in the output buffer), next_in is updated and processing
will resume at this point for the next call of inflate().
- Provide more output starting at next_out and update next_out and avail_out
accordingly. inflate() always provides as much output as possible
(until no more input data or no more space in the output buffer).
Before the call of inflate(), the application should ensure that at least
one of the actions is possible, by providing more input and/or consuming
more output, and updating the next_* and avail_* values accordingly.
The application can consume the uncompressed output when the output
buffer is full (avail_out == 0), or after each call of inflate().
If the parameter flush is set to Z_PARTIAL_FLUSH, inflate flushes as much
output as possible to the output buffer. The flushing behavior of inflate is
not specified for values of the flush paramater other than Z_PARTIAL_FLUSH
and Z_FINISH, but the current implementation actually flushes as much output
as possible anyway.
inflate() should normally be called until it returns Z_STREAM_END or an
error. However if all decompression is to be performed in a single step
(a single call of inflate), the parameter flush should be set to
Z_FINISH. In this case all pending input is processed and all pending
output is flushed; avail_out must be large enough to hold all the
uncompressed data. (The size of the uncompressed data may have been saved
by the compressor for this purpose.) The next operation on this stream must
be inflateEnd to deallocate the decompression state.
inflate() returns Z_OK if some progress has been made (more input
processed or more output produced), Z_STREAM_END if the end of the
compressed data has been reached, Z_DATA_ERROR if the input data was
corrupted, Z_STREAM_ERROR if the stream structure was inconsistent (for
example if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough
memory, Z_BUF_ERROR if no progress is possible or if there was not enough
room in the output buffer when Z_FINISH is used. In the Z_DATA_ERROR case,
the application may then call inflateSync to look for a good compression
block.
*/
extern int inflateEnd __P((z_stream *strm));
/*
All dynamically allocated data structures for this stream are freed.
This function discards any unprocessed input and does not flush any
pending output.
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
was inconsistent. In the error case, msg may be set but then points to a
static string (which must not be deallocated).
*/
/* advanced functions */
/*
The following functions are needed only in some special applications.
*/
extern int deflateInit2 __P((z_stream *strm,
int level,
int method,
int windowBits,
int memLevel,
int strategy));
/*
This is another version of deflateInit with more compression options. The
fields next_in, zalloc and zfree must be initialized before by the caller.
The method parameter is the compression method. It must be 8 in this
version of the library. (Method 9 will allow a 64K history buffer and
partial block flushes.)
The windowBits parameter is the base two logarithm of the window size
(the size of the history buffer). It should be in the range 8..15 for this
version of the library (the value 16 will be allowed soon). Larger values
of this parameter result in better compression at the expense of memory
usage. The default value is 15 if deflateInit is used instead.
The memLevel parameter specifies how much memory should be allocated
for the internal compression state. memLevel=1 uses minimum memory but
is slow and reduces compression ratio; memLevel=9 uses maximum memory
for optimal speed. The default value is 8.
The strategy parameter is used to tune the compression algorithm. Use
the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data
produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman
encoding only (no string match). Filtered data consists mostly of small
values with a somewhat random distribution. In this case, the
compression algorithm is tuned to compress them better. The strategy
parameter only affects the compression ratio but not the correctness of
the compressed output even if it is not set appropriately.
If next_in is not null, the library will use this buffer to hold also
some history information; the buffer must either hold the entire input
data, or have at least (1<<windowBits) bytes and be writable. If next_in is
null, the library will allocate its own history buffer (and leave next_in
null). next_out need not be provided here but must be provided by the
application for the next call of deflate().
If the history buffer is provided by the application, next_in must
must never be changed by the application since the compressor maintains
information inside this buffer from call to call; the application
must provide more input only by increasing avail_in. next_in is always
reset by the library in this case.
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
not enough memory, Z_STREAM_ERROR if the stream state was inconsistent
(such as zalloc being NULL) or the parameters are invalid (such as
an invalid method). msg is set to null if there is no error message.
deflateInit2 does not perform any compression: this will be done by
deflate().
*/
extern int deflateCopy __P((z_stream *dest,
z_stream *source));
/*
Sets the destination stream as a complete copy of the source stream. If
the source stream is using an application-supplied history buffer, a new
buffer is allocated for the destination stream. The compressed output
buffer is always application-supplied. It's the responsability of the
application to provide the correct values of next_out and avail_out for the
next call of deflate.
This function is useful when several compression strategies will be
tried, for example when there are several ways of pre-processing the input
data with a filter. The streams that will be discarded should then be freed
by calling deflateEnd. Note that deflateCopy duplicates the internal
compression state which can be quite large, so this strategy is slow and
can consume lots of memory.
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
(such as zalloc being NULL). msg is left unchanged in both source and
destination.
*/
extern int deflateReset __P((z_stream *strm));
/*
This function is equivalent to deflateEnd followed by deflateInit,
but does not free and reallocate all the internal compression state.
The stream will keep the same compression level and any other attributes
that may have been set by deflateInit2.
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
stream state was inconsistent (such as zalloc or state being NULL).
*/
extern int inflateInit2 __P((z_stream *strm,
int windowBits));
/*
This is another version of inflateInit with more compression options. The
fields next_out, zalloc and zfree must be initialized before by the caller.
The windowBits parameter is the base two logarithm of the maximum window
size (the size of the history buffer). It should be in the range 8..15 for
this version of the library (the value 16 will be allowed soon). The
default value is 15 if inflateInit is used instead. If a compressed stream
with a larger window size is given as input, inflate() will return with
the error code Z_DATA_ERROR instead of trying to allocate a larger window.
If next_out is not null, the library will use this buffer for the history
buffer; the buffer must either be large enough to hold the entire output
data, or have at least 1<<(windowBits-1) bytes. If next_out is null, the
library will allocate its own buffer (and leave next_out null). next_in
need not be provided here but must be provided by the application for the
next call of inflate().
If the history buffer is provided by the application, next_out must
never be changed by the application since the decompressor maintains
history information inside this buffer from call to call; the application
can only reset next_out to the beginning of the history buffer when
avail_out is zero and all output has been consumed.
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
not enough memory, Z_STREAM_ERROR if the stream state was inconsistent
(such as zalloc being NULL) or the parameters are invalid (such as
windowBits < 9). msg is set to null if there is no error message.
inflateInit2 does not perform any compression: this will be done by
inflate().
*/
extern int inflateSync __P((z_stream *strm));
/*
Skips invalid compressed data until the special marker and a valid block
can be found, or until all available input is skipped. No output is provided.
inflateSync returns Z_OK if a valid block has been found, Z_BUF_ERROR if
no more input was provided, Z_DATA_ERROR if not valid block has been found,
Z_STREAM_ERROR if the stream structure was inconsistent. In the success
case, the application may save the current current value of total_in which
indicates where valid compressed data was found. In the error case, the
application may repeatedly call inflateSync, providing more input each time,
until success or end of the input data.
*/
extern int inflateReset __P((z_stream *strm));
/*
This function is equivalent to inflateEnd followed by inflateInit,
but does not free and reallocate all the internal decompression state.
The stream will keep attributes that may have been set by inflateInit2.
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
stream state was inconsistent (such as zalloc or state being NULL).
*/
/* utility functions */
/*
The following utility functions are implemented on top of the
basic stream-oriented functions. To simplify the interface, some
default options are assumed (compression level, window size,
standard memory allocation functions). The source code of these
utility functions can easily be modified if you need special options.
*/
extern int compress __P((Byte *dest, uLong *destLen,
Byte *source, uLong sourceLen));
/*
Compresses the source buffer into the destination buffer. sourceLen is
the byte length of the source buffer. Upon entry, destLen is the total
size of the destination buffer, which must be at least 0.1% larger than
sourceLen plus 8 bytes. Upon exit, destLen is the actual size of the
compressed buffer.
This function can be used to compress a whole file at once if the
input file is mmap'ed.
compress returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_BUF_ERROR if there was not enough room in the output
buffer.
*/
extern int uncompress __P((Byte *dest, uLong *destLen,
Byte *source, uLong sourceLen));
/*
Decompresses the source buffer into the destination buffer. sourceLen is
the byte length of the source buffer. Upon entry, destLen is the total
size of the destination buffer, which must be large enough to hold the
entire uncompressed data. (The size of the uncompressed data must have
been saved previously by the compressor and transmitted to the decompressor
by some mechanism outside the scope of this compression library.)
Upon exit, destLen is the actual size of the compressed buffer.
This function can be used to decompress a whole file at once if the
input file is mmap'ed.
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_BUF_ERROR if there was not enough room in the output
buffer, or Z_DATA_ERROR if the input data was corrupted.
*/
typedef voidp gzFile;
extern gzFile gzopen __P((char *path, char *mode));
/*
Opens a gzip (.gz) file for reading or writing. The mode parameter
is as in fopen ("rb" or "wb"). gzopen can also be used to read a file
which is not in gzip format; in this case gzread will directly read from
the file without decompression.
gzopen return NULL if the file could not be opened or if there was
insufficient memory to allocate the (de)compression state; errno
can be checked to distinguish the two cases (if errno is zero, the
zlib error is Z_MEM_ERROR).
*/
extern gzFile gzdopen __P((int fd, char *mode));
/*
gzdopen() associates a gzFile with the file descriptor fd. File
descriptors are obtained from calls like open, dup, creat, or pipe.
The mode parameter is as in fopen ("rb" or "wb").
gzdopen return NULL if there was insufficient memory to allocate
the (de)compression state.
*/
extern int gzread __P((gzFile file, voidp buf, unsigned len));
/*
Reads the given number of uncompressed bytes from the compressed file.
If the input file was not in gzip format, gzread copies the given number
of bytes into the buffer.
gzread returns the number of uncompressed bytes actually read (0 for
end of file, -1 for error). */
extern int gzwrite __P((gzFile file, voidp buf, unsigned len));
/*
Writes the given number of uncompressed bytes into the compressed file.
gzwrite returns the number of uncompressed bytes actually written
(0 in case of error).
*/
extern int gzflush __P((gzFile file, int flush));
/*
Flushes all pending output into the compressed file. The parameter
flush is as in the deflate() function. The return value is the zlib
error number (see function gzerror below).
gzflush should be called only when strictly necessary because it can
degrade compression.
*/
extern int gzclose __P((gzFile file));
/*
Flushes all pending output if necessary, closes the compressed file
and deallocates all the (de)compression state. The return value is the zlib
error number (see function gzerror below).
*/
extern char* gzerror __P((gzFile file, int *errnum));
/*
Returns the error message for the last error which occurred on the
given compressed file. errnum is set to zlib error number. If an
error occurred in the file system and not in the compression library,
errnum is set to Z_ERRNO and the application may consult errno
to get the exact error code.
*/
/* checksum functions */
/*
These functions are not related to compression but are exported
anyway because they might be useful in applications using the
compression library.
*/
extern uLong adler32 __P((uLong adler, Byte *buf, uInt len));
/*
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
return the updated checksum. If buf is NULL, this function returns
the required initial value for the checksum.
An Adler-32 cheksum is almost as reliable as a CRC32 but can be computed
much faster. Usage example:
uLong adler = adler32(0L, Z_NULL, 0);
while (read_buffer(buffer, length) != EOF) {
adler = adler32(adler, buffer, length);
}
if (adler != original_adler) error();
*/
extern uLong crc32 __P((uLong crc, Byte *buf, uInt len));
/*
Update a running crc with the bytes buf[0..len-1] and return the updated
crc. If buf is NULL, this function returns the required initial value
for the crc (0). Pre- and post-conditioning (one's complement) is performed
within this function so it shouldn't be done by the application.
Usage example:
uLong crc = crc32(0L, Z_NULL, 0);
while (read_buffer(buffer, length) != EOF) {
crc = crc32(crc, buffer, length);
}
if (crc != original_crc) error();
*/
#ifndef _Z_UTIL_H
struct internal_state {int dummy;}; /* hack for buggy compilers */
#endif
#endif /* _ZLIB_H */

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/* zutil.c -- target dependent utility functions for the compression library
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: zutil.c,v 1.3 1995/04/10 09:52:26 jloup Exp $ */
#include <stdio.h>
#include "zutil.h"
char *zlib_version = ZLIB_VERSION;
char *z_errmsg[] = {
"stream end", /* Z_STREAM_END 1 */
"", /* Z_OK 0 */
"file error", /* Z_ERRNO (-1) */
"stream error", /* Z_STREAM_ERROR (-2) */
"data error", /* Z_DATA_ERROR (-3) */
"insufficient memory", /* Z_MEM_ERROR (-4) */
"buffer error", /* Z_BUF_ERROR (-5) */
""};
void z_error (m)
char *m;
{
fprintf(stderr, "%s\n", m);
exit(1);
}
#ifndef HAVE_MEMCPY
void zmemcpy(dest, source, len)
Byte* dest;
Byte* source;
uInt len;
{
if (len == 0) return;
do {
*dest++ = *source++; /* ??? to be unrolled */
} while (--len != 0);
}
void zmemzero(dest, len)
Byte* dest;
uInt len;
{
if (len == 0) return;
do {
*dest++ = 0; /* ??? to be unrolled */
} while (--len != 0);
}
#endif
#if defined(MSDOS) && !defined(USE_CALLOC)
# ifdef __TURBOC__
/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
* and farmalloc(64K) returns a pointer with an offset of 8, so we
* must fix the pointer. Warning: the pointer must be put back to its
* original form in order to free it, use zcfree().
*/
#define MAX_PTR 10
/* 10*64K = 640K */
local int next_ptr = 0;
typedef struct ptr_table_s {
voidp org_ptr;
voidp new_ptr;
} ptr_table;
local ptr_table table[MAX_PTR];
/* This table is used to remember the original form of pointers
* to large buffers (64K). Such pointers are normalized with a zero offset.
* Since MSDOS is not a preemptive multitasking OS, this table is not
* protected from concurrent access. This hack doesn't work anyway on
* a protected system like OS/2. Use Microsoft C instead.
*/
voidp zcalloc (voidp opaque, unsigned items, unsigned size)
{
voidp buf;
ulg bsize = (ulg)items*size;
if (bsize < 65536L) {
buf = farmalloc(bsize);
if (*(ush*)&buf != 0) return buf;
} else {
buf = farmalloc(bsize + 16L);
}
if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
table[next_ptr].org_ptr = buf;
/* Normalize the pointer to seg:0 */
*((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
*(ush*)&buf = 0;
table[next_ptr++].new_ptr = buf;
return buf;
}
void zcfree (voidp opaque, voidp ptr)
{
int n;
if (*(ush*)&ptr != 0) { /* object < 64K */
farfree(ptr);
return;
}
/* Find the original pointer */
for (n = 0; n < next_ptr; n++) {
if (ptr != table[n].new_ptr) continue;
farfree(table[n].org_ptr);
while (++n < next_ptr) {
table[n-1] = table[n];
}
next_ptr--;
return;
}
z_error("zcfree: ptr not found");
}
# else /* MSC */
#if (!defined(_MSC_VER) || (_MSC_VER < 600))
# define _halloc halloc
# define _hfree hfree
#endif
voidp zcalloc (voidp opaque, unsigned items, unsigned size)
{
return _halloc((long)items, size);
}
void zcfree (voidp opaque, voidp ptr)
{
return _hfree(ptr);
}
# endif /* __TURBOC__ ? */
#else /* !MSDOS */
extern voidp calloc __P((uInt items, uInt size));
extern void free __P((voidp ptr));
voidp zcalloc (opaque, items, size)
voidp opaque;
unsigned items;
unsigned size;
{
return calloc(items, size);
}
void zcfree (opaque, ptr)
voidp opaque;
voidp ptr;
{
free(ptr);
}
#endif /* MSDOS */

166
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/* zutil.h -- internal interface and configuration of the compression library
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
/* $Id: zutil.h,v 1.4 1995/04/14 10:22:17 jloup Exp $ */
#ifndef _Z_UTIL_H
#define _Z_UTIL_H
#include "zlib.h"
#ifdef MSDOS
# include <stddef.h>
#else
extern int errno;
#endif
#ifndef local
# define local static
#endif
/* compile with -Dlocal if your debugger can't find static symbols */
typedef unsigned char uch;
typedef unsigned short ush;
typedef unsigned long ulg;
extern char *z_errmsg[]; /* indexed by 1-zlib_error */
#define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
/* To be used only when the state is known to be valid */
/* common constants */
#define DEFLATED 8
#ifndef WBITS
# define WBITS 15 /* 32K window */
#endif
#ifndef MEM_LEVEL
# define MEM_LEVEL 8
#endif
#define STORED_BLOCK 0
#define STATIC_TREES 1
#define DYN_TREES 2
/* The three kinds of block type */
#define MIN_MATCH 3
#define MAX_MATCH 258
/* The minimum and maximum match lengths */
/* target dependencies */
#ifdef MSDOS
# define OS_CODE 0x00
# ifdef __TURBOC__
# include <alloc.h>
# define exit(n) _exit(n)
# else /* MSC */
# include <malloc.h>
# endif
#endif
#ifdef OS2
# define OS_CODE 0x06
#endif
#ifdef WIN32 /* Windows NT */
# define OS_CODE 0x0b
#endif
#if defined(VAXC) || defined(VMS)
# define OS_CODE 0x02
# define FOPEN(name, mode) \
fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
#endif
#ifdef AMIGA
# define OS_CODE 0x01
#endif
#if defined(ATARI) || defined(atarist)
# define OS_CODE 0x05
#endif
#ifdef MACOS
# define OS_CODE 0x07
#endif
#ifdef __50SERIES /* Prime/PRIMOS */
# define OS_CODE 0x0F
#endif
#ifdef TOPS20
# define OS_CODE 0x0a
#endif
/* Common defaults */
#ifndef OS_CODE
# define OS_CODE 0x03 /* assume Unix */
#endif
#ifndef FOPEN
# define FOPEN(name, mode) fopen((name), (mode))
#endif
/* functions */
#ifdef HAVE_STRERROR
extern char *strerror __P((int));
# define zstrerror(errnum) strerror(errnum)
#else
# define zstrerror(errnum) ""
#endif
#if defined(__STDC__) && !defined(HAVE_MEMCPY)
# define HAVE_MEMCPY
#endif
#ifdef HAVE_MEMCPY
# define zmemcpy memcpy
# define zmemzero(dest, len) memset(dest, 0, len)
#else
extern void zmemcpy __P((Byte* dest, Byte* source, uInt len));
extern void zmemzero __P((Byte* dest, uInt len));
#endif
/* Diagnostic functions */
#ifdef DEBUG
# include <stdio.h>
# ifndef verbose
# define verbose 0
# endif
# define Assert(cond,msg) {if(!(cond)) z_error(msg);}
# define Trace(x) fprintf x
# define Tracev(x) {if (verbose) fprintf x ;}
# define Tracevv(x) {if (verbose>1) fprintf x ;}
# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
#else
# define Assert(cond,msg)
# define Trace(x)
# define Tracev(x)
# define Tracevv(x)
# define Tracec(c,x)
# define Tracecv(c,x)
#endif
extern void z_error __P((char *m));
voidp zcalloc __P((voidp opaque, unsigned items, unsigned size));
void zcfree __P((voidp opaque, voidp ptr));
#define ZALLOC(strm, items, size) (*strm->zalloc)(strm->opaque, items, size)
#define ZFREE(strm, addr) (*strm->zfree) (strm->opaque, (voidp)addr)
#define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
#endif /* _Z_UTIL_H */
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