From bcf78a20978d76f64b7cd46d1a4d7a79a578c77b Mon Sep 17 00:00:00 2001 From: Mark Adler Date: Fri, 9 Sep 2011 22:36:31 -0700 Subject: [PATCH] zlib 0.71 --- ChangeLog | 51 +++ Makefile | 59 +++ README | 57 +++ adler32.c | 46 +++ compress.c | 55 +++ crc32.c | 103 ++++++ deflate.c | 932 ++++++++++++++++++++++++++++++++++++++++++++++ deflate.h | 270 ++++++++++++++ example.c | 201 ++++++++++ gzio.c | 459 +++++++++++++++++++++++ infblock.c | 324 ++++++++++++++++ infblock.h | 26 ++ infcodes.c | 217 +++++++++++ infcodes.h | 25 ++ inflate.c | 221 +++++++++++ inflate.h | 22 ++ inftest.c | 67 ++++ inftrees.c | 471 +++++++++++++++++++++++ inftrees.h | 62 ++++ infutil.c | 76 ++++ infutil.h | 86 +++++ minigzip.c | 210 +++++++++++ trees.c | 1048 ++++++++++++++++++++++++++++++++++++++++++++++++++++ uncompr.c | 58 +++ zconf.h | 66 ++++ zlib.h | 604 ++++++++++++++++++++++++++++++ zutil.c | 164 ++++++++ zutil.h | 166 +++++++++ 28 files changed, 6146 insertions(+) create mode 100644 ChangeLog create mode 100644 Makefile create mode 100644 README create mode 100644 adler32.c create mode 100644 compress.c create mode 100644 crc32.c create mode 100644 deflate.c create mode 100644 deflate.h create mode 100644 example.c create mode 100644 gzio.c create mode 100644 infblock.c create mode 100644 infblock.h create mode 100644 infcodes.c create mode 100644 infcodes.h create mode 100644 inflate.c create mode 100644 inflate.h create mode 100644 inftest.c create mode 100644 inftrees.c create mode 100644 inftrees.h create mode 100644 infutil.c create mode 100644 infutil.h create mode 100644 minigzip.c create mode 100644 trees.c create mode 100644 uncompr.c create mode 100644 zconf.h create mode 100644 zlib.h create mode 100644 zutil.c create mode 100644 zutil.h diff --git a/ChangeLog b/ChangeLog new file mode 100644 index 00000000..40fc89f9 --- /dev/null +++ b/ChangeLog @@ -0,0 +1,51 @@ + 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() diff --git a/Makefile b/Makefile new file mode 100644 index 00000000..478920a1 --- /dev/null +++ b/Makefile @@ -0,0 +1,59 @@ +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 diff --git a/README b/README new file mode 100644 index 00000000..5c424025 --- /dev/null +++ b/README @@ -0,0 +1,57 @@ +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. diff --git a/adler32.c b/adler32.c new file mode 100644 index 00000000..0b2b820e --- /dev/null +++ b/adler32.c @@ -0,0 +1,46 @@ +/* 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; +} diff --git a/compress.c b/compress.c new file mode 100644 index 00000000..8edcb2ae --- /dev/null +++ b/compress.c @@ -0,0 +1,55 @@ +/* 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; +} diff --git a/crc32.c b/crc32.c new file mode 100644 index 00000000..e8d385fc --- /dev/null +++ b/crc32.c @@ -0,0 +1,103 @@ +/* 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 < 256; n++) + { + c = (uLong)n; + for (k = 0; k < 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 +}; diff --git a/deflate.c b/deflate.c new file mode 100644 index 00000000..2409f07b --- /dev/null +++ b/deflate.c @@ -0,0 +1,932 @@ +/* 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)<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; jins_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; +} diff --git a/deflate.h b/deflate.h new file mode 100644 index 00000000..740c25a4 --- /dev/null +++ b/deflate.h @@ -0,0 +1,270 @@ +/* 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)); diff --git a/example.c b/example.c new file mode 100644 index 00000000..ea1a9eb9 --- /dev/null +++ b/example.c @@ -0,0 +1,201 @@ +/* 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 +#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); +} diff --git a/gzio.c b/gzio.c new file mode 100644 index 00000000..b488e96a --- /dev/null +++ b/gzio.c @@ -0,0 +1,459 @@ +/* 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 + +#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; +} diff --git a/infblock.c b/infblock.c new file mode 100644 index 00000000..3a582809 --- /dev/null +++ b/infblock.c @@ -0,0 +1,324 @@ +/* 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; +} diff --git a/infblock.h b/infblock.h new file mode 100644 index 00000000..f70c471f --- /dev/null +++ b/infblock.h @@ -0,0 +1,26 @@ +/* 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 */ diff --git a/infcodes.c b/infcodes.c new file mode 100644 index 00000000..ffae26d4 --- /dev/null +++ b/infcodes.c @@ -0,0 +1,217 @@ +/* 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); +} diff --git a/infcodes.h b/infcodes.h new file mode 100644 index 00000000..af99cd12 --- /dev/null +++ b/infcodes.h @@ -0,0 +1,25 @@ +/* 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 *)); diff --git a/inflate.c b/inflate.c new file mode 100644 index 00000000..478f46d0 --- /dev/null +++ b/inflate.c @@ -0,0 +1,221 @@ +/* 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<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); +} diff --git a/inflate.h b/inflate.h new file mode 100644 index 00000000..843224f4 --- /dev/null +++ b/inflate.h @@ -0,0 +1,22 @@ +/* temporary kludge assuming single pass decompression */ + +/* $Id: inflate.h,v 1.2 1995/04/11 14:47:32 jloup Exp $ */ + +#include + +#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 diff --git a/inftest.c b/inftest.c new file mode 100644 index 00000000..7dc29079 --- /dev/null +++ b/inftest.c @@ -0,0 +1,67 @@ +#include +#include +#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); +} diff --git a/inftrees.c b/inftrees.c new file mode 100644 index 00000000..4b00e3ce --- /dev/null +++ b/inftrees.c @@ -0,0 +1,471 @@ +/* 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; +} diff --git a/inftrees.h b/inftrees.h new file mode 100644 index 00000000..6001a4e4 --- /dev/null +++ b/inftrees.h @@ -0,0 +1,62 @@ +/* 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 */ diff --git a/infutil.c b/infutil.c new file mode 100644 index 00000000..92d115fd --- /dev/null +++ b/infutil.c @@ -0,0 +1,76 @@ +/* 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; +} diff --git a/infutil.h b/infutil.h new file mode 100644 index 00000000..af073728 --- /dev/null +++ b/infutil.h @@ -0,0 +1,86 @@ +/* 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)<>=(j);k-=(j);} +/* output bytes */ +#define WAVAIL (qread?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 */ diff --git a/minigzip.c b/minigzip.c new file mode 100644 index 00000000..688b3a1b --- /dev/null +++ b/minigzip.c @@ -0,0 +1,210 @@ +/* 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 +#include "zlib.h" + +#ifdef MSDOS +# include +# 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); +} diff --git a/trees.c b/trees.c new file mode 100644 index 00000000..79cab9f8 --- /dev/null +++ b/trees.c @@ -0,0 +1,1048 @@ +/* trees.c -- output deflated data using Huffman coding + * Copyright (C) 1995 Jean-loup Gailly + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * ALGORITHM + * + * The "deflation" process uses several Huffman trees. The more + * common source values are represented by shorter bit sequences. + * + * Each code tree is stored in a compressed form which is itself + * a Huffman encoding of the lengths of all the code strings (in + * ascending order by source values). The actual code strings are + * reconstructed from the lengths in the inflate process, as described + * in the deflate specification. + * + * REFERENCES + * + * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". + * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc + * + * Storer, James A. + * Data Compression: Methods and Theory, pp. 49-50. + * Computer Science Press, 1988. ISBN 0-7167-8156-5. + * + * Sedgewick, R. + * Algorithms, p290. + * Addison-Wesley, 1983. ISBN 0-201-06672-6. + */ + +/* $Id: trees.c,v 1.2 1995/04/10 16:21:44 jloup Exp $ */ + +#include "deflate.h" + +#ifdef DEBUG +# include +#endif + +/* =========================================================================== + * Constants + */ + +#define MAX_BL_BITS 7 +/* Bit length codes must not exceed MAX_BL_BITS bits */ + +#define END_BLOCK 256 +/* end of block literal code */ + +#define REP_3_6 16 +/* repeat previous bit length 3-6 times (2 bits of repeat count) */ + +#define REPZ_3_10 17 +/* repeat a zero length 3-10 times (3 bits of repeat count) */ + +#define REPZ_11_138 18 +/* repeat a zero length 11-138 times (7 bits of repeat count) */ + +local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ + = {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}; + +local int extra_dbits[D_CODES] /* extra bits for each distance code */ + = {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}; + +local int extra_blbits[BL_CODES]/* extra bits for each bit length code */ + = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; + +local uch bl_order[BL_CODES] + = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; +/* The lengths of the bit length codes are sent in order of decreasing + * probability, to avoid transmitting the lengths for unused bit length codes. + */ + +#define Buf_size (8 * 2*sizeof(char)) +/* Number of bits used within bi_buf. (bi_buf might be implemented on + * more than 16 bits on some systems.) + */ + +/* =========================================================================== + * Local data. These are initialized only once. + * To do: initialize at compile time to be completely reentrant. ??? + */ + +local ct_data static_ltree[L_CODES+2]; +/* The static literal tree. Since the bit lengths are imposed, there is no + * need for the L_CODES extra codes used during heap construction. However + * The codes 286 and 287 are needed to build a canonical tree (see ct_init + * below). + */ + +local ct_data static_dtree[D_CODES]; +/* The static distance tree. (Actually a trivial tree since all codes use + * 5 bits.) + */ + +local uch dist_code[512]; +/* distance codes. The first 256 values correspond to the distances + * 3 .. 258, the last 256 values correspond to the top 8 bits of + * the 15 bit distances. + */ + +local uch length_code[MAX_MATCH-MIN_MATCH+1]; +/* length code for each normalized match length (0 == MIN_MATCH) */ + +local int base_length[LENGTH_CODES]; +/* First normalized length for each code (0 = MIN_MATCH) */ + +local int base_dist[D_CODES]; +/* First normalized distance for each code (0 = distance of 1) */ + +struct static_tree_desc_s { + ct_data *static_tree; /* static tree or NULL */ + int *extra_bits; /* extra bits for each code or NULL */ + int extra_base; /* base index for extra_bits */ + int elems; /* max number of elements in the tree */ + int max_length; /* max bit length for the codes */ +}; + +local static_tree_desc static_l_desc = +{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; + +local static_tree_desc static_d_desc = +{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; + +local static_tree_desc static_bl_desc = +{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; + +/* =========================================================================== + * Local (static) routines in this file. + */ + +local void ct_static_init __P((void)); +local void init_block __P((deflate_state *s)); +local void pqdownheap __P((deflate_state *s, ct_data *tree, int k)); +local void gen_bitlen __P((deflate_state *s, tree_desc *desc)); +local void gen_codes __P((ct_data *tree, int max_code, ush bl_count[])); +local void build_tree __P((deflate_state *s, tree_desc *desc)); +local void scan_tree __P((deflate_state *s, ct_data *tree, int max_code)); +local void send_tree __P((deflate_state *s, ct_data *tree, int max_code)); +local int build_bl_tree __P((deflate_state *s)); +local void send_all_trees __P((deflate_state *s, int lcodes, int dcodes, + int blcodes)); +local void compress_block __P((deflate_state *s, ct_data *ltree, + ct_data *dtree)); +local void set_data_type __P((deflate_state *s)); +local void send_bits __P((deflate_state *s, int value, int length)); +local unsigned bi_reverse __P((unsigned value, int length)); +local void bi_windup __P((deflate_state *s)); +local void copy_block __P((deflate_state *s, char *buf, unsigned len, + int header)); + +#ifndef DEBUG +# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) + /* Send a code of the given tree. c and tree must not have side effects */ + +#else /* DEBUG */ +# define send_code(s, c, tree) \ + { if (verbose>1) fprintf(stderr,"\ncd %3d ",(c)); \ + send_bits(s, tree[c].Code, tree[c].Len); } +#endif + +#define d_code(dist) \ + ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) +/* Mapping from a distance to a distance code. dist is the distance - 1 and + * must not have side effects. dist_code[256] and dist_code[257] are never + * used. + */ + +#define MAX(a,b) (a >= b ? a : b) +/* the arguments must not have side effects */ + +/* =========================================================================== + * Initialize the various 'constant' tables. + * To do: do this at compile time. + */ +local void ct_static_init() +{ + int n; /* iterates over tree elements */ + int bits; /* bit counter */ + int length; /* length value */ + int code; /* code value */ + int dist; /* distance index */ + ush bl_count[MAX_BITS+1]; + /* number of codes at each bit length for an optimal tree */ + + /* Initialize the mapping length (0..255) -> length code (0..28) */ + length = 0; + for (code = 0; code < LENGTH_CODES-1; code++) { + base_length[code] = length; + for (n = 0; n < (1< dist code (0..29) */ + dist = 0; + for (code = 0 ; code < 16; code++) { + base_dist[code] = dist; + for (n = 0; n < (1<>= 7; /* from now on, all distances are divided by 128 */ + for ( ; code < D_CODES; code++) { + base_dist[code] = dist << 7; + for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { + dist_code[256 + dist++] = (uch)code; + } + } + Assert (dist == 256, "ct_static_init: 256+dist != 512"); + + /* Construct the codes of the static literal tree */ + for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; + n = 0; + while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; + while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; + while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; + while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; + /* Codes 286 and 287 do not exist, but we must include them in the + * tree construction to get a canonical Huffman tree (longest code + * all ones) + */ + gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); + + /* The static distance tree is trivial: */ + for (n = 0; n < D_CODES; n++) { + static_dtree[n].Len = 5; + static_dtree[n].Code = bi_reverse(n, 5); + } +} + +/* =========================================================================== + * Initialize the tree data structures for a new zlib stream. + */ +void ct_init(s) + deflate_state *s; +{ + if (static_dtree[0].Len == 0) { + ct_static_init(); /* To do: at compile time */ + } + + s->compressed_len = 0L; + + s->l_desc.dyn_tree = s->dyn_ltree; + s->l_desc.stat_desc = &static_l_desc; + + s->d_desc.dyn_tree = s->dyn_dtree; + s->d_desc.stat_desc = &static_d_desc; + + s->bl_desc.dyn_tree = s->bl_tree; + s->bl_desc.stat_desc = &static_bl_desc; + + s->bi_buf = 0; + s->bi_valid = 0; +#ifdef DEBUG + s->bits_sent = 0L; +#endif + + /* Initialize the first block of the first file: */ + init_block(s); +} + +/* =========================================================================== + * Initialize a new block. + */ +local void init_block(s) + deflate_state *s; +{ + int n; /* iterates over tree elements */ + + /* Initialize the trees. */ + for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; + for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; + for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; + + s->dyn_ltree[END_BLOCK].Freq = 1; + s->opt_len = s->static_len = 0L; + s->last_lit = s->matches = 0; +} + +#define SMALLEST 1 +/* Index within the heap array of least frequent node in the Huffman tree */ + + +/* =========================================================================== + * Remove the smallest element from the heap and recreate the heap with + * one less element. Updates heap and heap_len. + */ +#define pqremove(s, tree, top) \ +{\ + top = s->heap[SMALLEST]; \ + s->heap[SMALLEST] = s->heap[s->heap_len--]; \ + pqdownheap(s, tree, SMALLEST); \ +} + +/* =========================================================================== + * Compares to subtrees, using the tree depth as tie breaker when + * the subtrees have equal frequency. This minimizes the worst case length. + */ +#define smaller(tree, n, m, depth) \ + (tree[n].Freq < tree[m].Freq || \ + (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) + +/* =========================================================================== + * Restore the heap property by moving down the tree starting at node k, + * exchanging a node with the smallest of its two sons if necessary, stopping + * when the heap property is re-established (each father smaller than its + * two sons). + */ +local void pqdownheap(s, tree, k) + deflate_state *s; + ct_data *tree; /* the tree to restore */ + int k; /* node to move down */ +{ + int v = s->heap[k]; + int j = k << 1; /* left son of k */ + while (j <= s->heap_len) { + /* Set j to the smallest of the two sons: */ + if (j < s->heap_len && + smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { + j++; + } + /* Exit if v is smaller than both sons */ + if (smaller(tree, v, s->heap[j], s->depth)) break; + + /* Exchange v with the smallest son */ + s->heap[k] = s->heap[j]; k = j; + + /* And continue down the tree, setting j to the left son of k */ + j <<= 1; + } + s->heap[k] = v; +} + +/* =========================================================================== + * Compute the optimal bit lengths for a tree and update the total bit length + * for the current block. + * IN assertion: the fields freq and dad are set, heap[heap_max] and + * above are the tree nodes sorted by increasing frequency. + * OUT assertions: the field len is set to the optimal bit length, the + * array bl_count contains the frequencies for each bit length. + * The length opt_len is updated; static_len is also updated if stree is + * not null. + */ +local void gen_bitlen(s, desc) + deflate_state *s; + tree_desc *desc; /* the tree descriptor */ +{ + ct_data *tree = desc->dyn_tree; + int max_code = desc->max_code; + ct_data *stree = desc->stat_desc->static_tree; + int *extra = desc->stat_desc->extra_bits; + int base = desc->stat_desc->extra_base; + int max_length = desc->stat_desc->max_length; + int h; /* heap index */ + int n, m; /* iterate over the tree elements */ + int bits; /* bit length */ + int xbits; /* extra bits */ + ush f; /* frequency */ + int overflow = 0; /* number of elements with bit length too large */ + + for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; + + /* In a first pass, compute the optimal bit lengths (which may + * overflow in the case of the bit length tree). + */ + tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ + + for (h = s->heap_max+1; h < HEAP_SIZE; h++) { + n = s->heap[h]; + bits = tree[tree[n].Dad].Len + 1; + if (bits > max_length) bits = max_length, overflow++; + tree[n].Len = (ush)bits; + /* We overwrite tree[n].Dad which is no longer needed */ + + if (n > max_code) continue; /* not a leaf node */ + + s->bl_count[bits]++; + xbits = 0; + if (n >= base) xbits = extra[n-base]; + f = tree[n].Freq; + s->opt_len += (ulg)f * (bits + xbits); + if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); + } + if (overflow == 0) return; + + Trace((stderr,"\nbit length overflow\n")); + /* This happens for example on obj2 and pic of the Calgary corpus */ + + /* Find the first bit length which could increase: */ + do { + bits = max_length-1; + while (s->bl_count[bits] == 0) bits--; + s->bl_count[bits]--; /* move one leaf down the tree */ + s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ + s->bl_count[max_length]--; + /* The brother of the overflow item also moves one step up, + * but this does not affect bl_count[max_length] + */ + overflow -= 2; + } while (overflow > 0); + + /* Now recompute all bit lengths, scanning in increasing frequency. + * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all + * lengths instead of fixing only the wrong ones. This idea is taken + * from 'ar' written by Haruhiko Okumura.) + */ + for (bits = max_length; bits != 0; bits--) { + n = s->bl_count[bits]; + while (n != 0) { + m = s->heap[--h]; + if (m > max_code) continue; + if (tree[m].Len != (unsigned) bits) { + Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); + s->opt_len += ((long)bits - (long)tree[m].Len) + *(long)tree[m].Freq; + tree[m].Len = (ush)bits; + } + n--; + } + } +} + +/* =========================================================================== + * Generate the codes for a given tree and bit counts (which need not be + * optimal). + * IN assertion: the array bl_count contains the bit length statistics for + * the given tree and the field len is set for all tree elements. + * OUT assertion: the field code is set for all tree elements of non + * zero code length. + */ +local void gen_codes (tree, max_code, bl_count) + ct_data *tree; /* the tree to decorate */ + int max_code; /* largest code with non zero frequency */ + ush bl_count[]; /* number of codes at each bit length */ +{ + ush next_code[MAX_BITS+1]; /* next code value for each bit length */ + ush code = 0; /* running code value */ + int bits; /* bit index */ + int n; /* code index */ + + /* The distribution counts are first used to generate the code values + * without bit reversal. + */ + for (bits = 1; bits <= MAX_BITS; bits++) { + next_code[bits] = code = (code + bl_count[bits-1]) << 1; + } + /* Check that the bit counts in bl_count are consistent. The last code + * must be all ones. + */ + Assert (code + bl_count[MAX_BITS]-1 == (1<dyn_tree; + ct_data *stree = desc->stat_desc->static_tree; + int elems = desc->stat_desc->elems; + int n, m; /* iterate over heap elements */ + int max_code = -1; /* largest code with non zero frequency */ + int node = elems; /* next internal node of the tree */ + int new; /* new node being created */ + + /* Construct the initial heap, with least frequent element in + * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. + * heap[0] is not used. + */ + s->heap_len = 0, s->heap_max = HEAP_SIZE; + + for (n = 0; n < elems; n++) { + if (tree[n].Freq != 0) { + s->heap[++(s->heap_len)] = max_code = n; + s->depth[n] = 0; + } else { + tree[n].Len = 0; + } + } + + /* The pkzip format requires that at least one distance code exists, + * and that at least one bit should be sent even if there is only one + * possible code. So to avoid special checks later on we force at least + * two codes of non zero frequency. + */ + while (s->heap_len < 2) { + new = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); + tree[new].Freq = 1; + s->depth[new] = 0; + s->opt_len--; if (stree) s->static_len -= stree[new].Len; + /* new is 0 or 1 so it does not have extra bits */ + } + desc->max_code = max_code; + + /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, + * establish sub-heaps of increasing lengths: + */ + for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); + + /* Construct the Huffman tree by repeatedly combining the least two + * frequent nodes. + */ + do { + pqremove(s, tree, n); /* n = node of least frequency */ + m = s->heap[SMALLEST]; /* m = node of next least frequency */ + + s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ + s->heap[--(s->heap_max)] = m; + + /* Create a new node father of n and m */ + tree[node].Freq = tree[n].Freq + tree[m].Freq; + s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); + tree[n].Dad = tree[m].Dad = (ush)node; +#ifdef DUMP_BL_TREE + if (tree == s->bl_tree) { + fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", + node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); + } +#endif + /* and insert the new node in the heap */ + s->heap[SMALLEST] = node++; + pqdownheap(s, tree, SMALLEST); + + } while (s->heap_len >= 2); + + s->heap[--(s->heap_max)] = s->heap[SMALLEST]; + + /* At this point, the fields freq and dad are set. We can now + * generate the bit lengths. + */ + gen_bitlen(s, (tree_desc *)desc); + + /* The field len is now set, we can generate the bit codes */ + gen_codes ((ct_data *)tree, max_code, s->bl_count); +} + +/* =========================================================================== + * Scan a literal or distance tree to determine the frequencies of the codes + * in the bit length tree. + */ +local void scan_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + if (nextlen == 0) max_count = 138, min_count = 3; + tree[max_code+1].Len = (ush)0xffff; /* guard */ + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + s->bl_tree[curlen].Freq += count; + } else if (curlen != 0) { + if (curlen != prevlen) s->bl_tree[curlen].Freq++; + s->bl_tree[REP_3_6].Freq++; + } else if (count <= 10) { + s->bl_tree[REPZ_3_10].Freq++; + } else { + s->bl_tree[REPZ_11_138].Freq++; + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Send a literal or distance tree in compressed form, using the codes in + * bl_tree. + */ +local void send_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + /* tree[max_code+1].Len = -1; */ /* guard already set */ + if (nextlen == 0) max_count = 138, min_count = 3; + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + do { send_code(s, curlen, s->bl_tree); } while (--count != 0); + + } else if (curlen != 0) { + if (curlen != prevlen) { + send_code(s, curlen, s->bl_tree); count--; + } + Assert(count >= 3 && count <= 6, " 3_6?"); + send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); + + } else if (count <= 10) { + send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); + + } else { + send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Construct the Huffman tree for the bit lengths and return the index in + * bl_order of the last bit length code to send. + */ +local int build_bl_tree(s) + deflate_state *s; +{ + int max_blindex; /* index of last bit length code of non zero freq */ + + /* Determine the bit length frequencies for literal and distance trees */ + scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); + scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); + + /* Build the bit length tree: */ + build_tree(s, (tree_desc *)(&(s->bl_desc))); + /* opt_len now includes the length of the tree representations, except + * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. + */ + + /* Determine the number of bit length codes to send. The pkzip format + * requires that at least 4 bit length codes be sent. (appnote.txt says + * 3 but the actual value used is 4.) + */ + for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { + if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; + } + /* Update opt_len to include the bit length tree and counts */ + s->opt_len += 3*(max_blindex+1) + 5+5+4; + Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", + s->opt_len, s->static_len)); + + return max_blindex; +} + +/* =========================================================================== + * Send the header for a block using dynamic Huffman trees: the counts, the + * lengths of the bit length codes, the literal tree and the distance tree. + * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. + */ +local void send_all_trees(s, lcodes, dcodes, blcodes) + deflate_state *s; + int lcodes, dcodes, blcodes; /* number of codes for each tree */ +{ + int rank; /* index in bl_order */ + + Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); + Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, + "too many codes"); + Tracev((stderr, "\nbl counts: ")); + send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ + send_bits(s, dcodes-1, 5); + send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ + for (rank = 0; rank < blcodes; rank++) { + Tracev((stderr, "\nbl code %2d ", bl_order[rank])); + send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); + } + Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ + Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ + Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); +} + +/* =========================================================================== + * Determine the best encoding for the current block: dynamic trees, static + * trees or store, and output the encoded block to the zip file. This function + * returns the total compressed length for the file so far. + */ +ulg ct_flush_block(s, buf, stored_len, eof) + deflate_state *s; + char *buf; /* input block, or NULL if too old */ + ulg stored_len; /* length of input block */ + int eof; /* true if this is the last block for a file */ +{ + ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ + int max_blindex; /* index of last bit length code of non zero freq */ + + /* Check if the file is ascii or binary */ + if (s->data_type == UNKNOWN) set_data_type(s); + + /* Construct the literal and distance trees */ + build_tree(s, (tree_desc *)(&(s->l_desc))); + Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + + build_tree(s, (tree_desc *)(&(s->d_desc))); + Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + /* At this point, opt_len and static_len are the total bit lengths of + * the compressed block data, excluding the tree representations. + */ + + /* Build the bit length tree for the above two trees, and get the index + * in bl_order of the last bit length code to send. + */ + max_blindex = build_bl_tree(s); + + /* Determine the best encoding. Compute first the block length in bytes */ + opt_lenb = (s->opt_len+3+7)>>3; + static_lenb = (s->static_len+3+7)>>3; + + Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", + opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, + s->last_lit)); + + if (static_lenb <= opt_lenb) opt_lenb = static_lenb; + + /* If compression failed and this is the first and last block, + * and if the .zip file can be seeked (to rewrite the local header), + * the whole file is transformed into a stored file: + */ +#ifdef STORED_FILE_OK +# ifdef FORCE_METHOD + if (level == 1 && eof && compressed_len == 0L) { /* force stored file */ +# else + if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) { +# endif + /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ + if (buf == (char*)0) error ("block vanished"); + + copy_block(buf, (unsigned)stored_len, 0); /* without header */ + s->compressed_len = stored_len << 3; + s->method = STORED; + } else +#endif /* STORED_FILE_OK */ + +#ifdef FORCE_METHOD + if (level == 2 && buf != (char*)0) { /* force stored block */ +#else + if (stored_len+4 <= opt_lenb && buf != (char*)0) { + /* 4: two words for the lengths */ +#endif + /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. + * Otherwise we can't have processed more than WSIZE input bytes since + * the last block flush, because compression would have been + * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to + * transform a block into a stored block. + */ + send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ + s->compressed_len = (s->compressed_len + 3 + 7) & ~7L; + s->compressed_len += (stored_len + 4) << 3; + + copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ + +#ifdef FORCE_METHOD + } else if (level == 3) { /* force static trees */ +#else + } else if (static_lenb == opt_lenb) { +#endif + send_bits(s, (STATIC_TREES<<1)+eof, 3); + compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); + s->compressed_len += 3 + s->static_len; + } else { + send_bits(s, (DYN_TREES<<1)+eof, 3); + send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, + max_blindex+1); + compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); + s->compressed_len += 3 + s->opt_len; + } + Assert (s->compressed_len == s->bits_sent, "bad compressed size"); + init_block(s); + + if (eof) { + bi_windup(s); + s->compressed_len += 7; /* align on byte boundary */ + } + Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, + s->compressed_len-7*eof)); + + return s->compressed_len >> 3; +} + +/* =========================================================================== + * Save the match info and tally the frequency counts. Return true if + * the current block must be flushed. + */ +int ct_tally (s, dist, lc) + deflate_state *s; + int dist; /* distance of matched string */ + int lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ +{ + s->d_buf[s->last_lit] = (ush)dist; + s->l_buf[s->last_lit++] = (uch)lc; + if (dist == 0) { + /* lc is the unmatched char */ + s->dyn_ltree[lc].Freq++; + } else { + s->matches++; + /* Here, lc is the match length - MIN_MATCH */ + dist--; /* dist = match distance - 1 */ + Assert((ush)dist < (ush)MAX_DIST(s) && + (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && + (ush)d_code(dist) < (ush)D_CODES, "ct_tally: bad match"); + + s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++; + s->dyn_dtree[d_code(dist)].Freq++; + } + + /* Try to guess if it is profitable to stop the current block here */ + if (s->level > 2 && (s->last_lit & 0xfff) == 0) { + /* Compute an upper bound for the compressed length */ + ulg out_length = (ulg)s->last_lit*8L; + ulg in_length = (ulg)s->strstart - s->block_start; + int dcode; + for (dcode = 0; dcode < D_CODES; dcode++) { + out_length += (ulg)s->dyn_dtree[dcode].Freq * + (5L+extra_dbits[dcode]); + } + out_length >>= 3; + Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", + s->last_lit, in_length, out_length, + 100L - out_length*100L/in_length)); + if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; + } + return (s->last_lit == s->lit_bufsize-1); + /* We avoid equality with lit_bufsize because of wraparound at 64K + * on 16 bit machines and because stored blocks are restricted to + * 64K-1 bytes. + */ +} + +/* =========================================================================== + * Send the block data compressed using the given Huffman trees + */ +local void compress_block(s, ltree, dtree) + deflate_state *s; + ct_data *ltree; /* literal tree */ + ct_data *dtree; /* distance tree */ +{ + unsigned dist; /* distance of matched string */ + int lc; /* match length or unmatched char (if dist == 0) */ + unsigned lx = 0; /* running index in l_buf */ + unsigned code; /* the code to send */ + int extra; /* number of extra bits to send */ + + if (s->last_lit != 0) do { + dist = s->d_buf[lx]; + lc = s->l_buf[lx++]; + if (dist == 0) { + send_code(s, lc, ltree); /* send a literal byte */ + Tracecv(isgraph(lc), (stderr," '%c' ", lc)); + } else { + /* Here, lc is the match length - MIN_MATCH */ + code = length_code[lc]; + send_code(s, code+LITERALS+1, ltree); /* send the length code */ + extra = extra_lbits[code]; + if (extra != 0) { + lc -= base_length[code]; + send_bits(s, lc, extra); /* send the extra length bits */ + } + dist--; /* dist is now the match distance - 1 */ + code = d_code(dist); + Assert (code < D_CODES, "bad d_code"); + + send_code(s, code, dtree); /* send the distance code */ + extra = extra_dbits[code]; + if (extra != 0) { + dist -= base_dist[code]; + send_bits(s, dist, extra); /* send the extra distance bits */ + } + } /* literal or match pair ? */ + + /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ + Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); + + } while (lx < s->last_lit); + + send_code(s, END_BLOCK, ltree); +} + +/* =========================================================================== + * Set the data type to ASCII or BINARY, using a crude approximation: + * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. + * IN assertion: the fields freq of dyn_ltree are set and the total of all + * frequencies does not exceed 64K (to fit in an int on 16 bit machines). + */ +local void set_data_type(s) + deflate_state *s; +{ + int n = 0; + unsigned ascii_freq = 0; + unsigned bin_freq = 0; + while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; + while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; + while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; + s->data_type = bin_freq > (ascii_freq >> 2) ? BINARY : ASCII; +} + +/* =========================================================================== + * Output a short LSB first on the stream. + * IN assertion: there is enough room in pendingBuf. + */ +#define put_short(s, w) { \ + put_byte(s, (uch)((w) & 0xff)); \ + put_byte(s, (uch)((ush)(w) >> 8)); \ +} + +/* =========================================================================== + * Send a value on a given number of bits. + * IN assertion: length <= 16 and value fits in length bits. + */ +local void send_bits(s, value, length) + deflate_state *s; + int value; /* value to send */ + int length; /* number of bits */ +{ +#ifdef DEBUG + Tracev((stderr," l %2d v %4x ", length, value)); + Assert(length > 0 && length <= 15, "invalid length"); + s->bits_sent += (ulg)length; +#endif + /* If not enough room in bi_buf, use (valid) bits from bi_buf and + * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) + * unused bits in value. + */ + if (s->bi_valid > (int)Buf_size - length) { + s->bi_buf |= (value << s->bi_valid); + put_short(s, s->bi_buf); + s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); + s->bi_valid += length - Buf_size; + } else { + s->bi_buf |= value << s->bi_valid; + s->bi_valid += length; + } +} + +/* =========================================================================== + * Reverse the first len bits of a code, using straightforward code (a faster + * method would use a table) + * IN assertion: 1 <= len <= 15 + */ +local unsigned bi_reverse(code, len) + unsigned code; /* the value to invert */ + int len; /* its bit length */ +{ + register unsigned res = 0; + do { + res |= code & 1; + code >>= 1, res <<= 1; + } while (--len > 0); + return res >> 1; +} + +/* =========================================================================== + * Write out any remaining bits in an incomplete byte. + */ +local void bi_windup(s) + deflate_state *s; +{ + if (s->bi_valid > 8) { + put_short(s, s->bi_buf); + } else if (s->bi_valid > 0) { + put_byte(s, s->bi_buf); + } + s->bi_buf = 0; + s->bi_valid = 0; +#ifdef DEBUG + s->bits_sent = (s->bits_sent+7) & ~7; +#endif +} + +/* =========================================================================== + * Copy a stored block, storing first the length and its + * one's complement if requested. + */ +local void copy_block(s, buf, len, header) + deflate_state *s; + char *buf; /* the input data */ + unsigned len; /* its length */ + int header; /* true if block header must be written */ +{ + bi_windup(s); /* align on byte boundary */ + + if (header) { + put_short(s, (ush)len); + put_short(s, (ush)~len); +#ifdef DEBUG + s->bits_sent += 2*16; +#endif + } +#ifdef DEBUG + s->bits_sent += (ulg)len<<3; +#endif + while (len--) { + put_byte(s, *buf++); + } +} diff --git a/uncompr.c b/uncompr.c new file mode 100644 index 00000000..4c8b3af0 --- /dev/null +++ b/uncompr.c @@ -0,0 +1,58 @@ +/* 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; +} diff --git a/zconf.h b/zconf.h new file mode 100644 index 00000000..29496d72 --- /dev/null +++ b/zconf.h @@ -0,0 +1,66 @@ +/* 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 */ + diff --git a/zlib.h b/zlib.h new file mode 100644 index 00000000..d1f2ca96 --- /dev/null +++ b/zlib.h @@ -0,0 +1,604 @@ +/* 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< + +#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 */ diff --git a/zutil.h b/zutil.h new file mode 100644 index 00000000..a1108e62 --- /dev/null +++ b/zutil.h @@ -0,0 +1,166 @@ +/* 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 +#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 +# define exit(n) _exit(n) +# else /* MSC */ +# include +# 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 +# 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 */