| /* vi: set sw=4 ts=4: */ |
| /* |
| * Gzip implementation for busybox |
| * |
| * Based on GNU gzip Copyright (C) 1992-1993 Jean-loup Gailly. |
| * |
| * Originally adjusted for busybox by Sven Rudolph <sr1@inf.tu-dresden.de> |
| * based on gzip sources |
| * |
| * Adjusted further by Erik Andersen <andersen@lineo.com>, <andersee@debian.org> |
| * to support files as well as stdin/stdout, and to generally behave itself wrt |
| * command line handling. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| * |
| */ |
| |
| #include "internal.h" |
| #include <getopt.h> |
| |
| /* These defines are very important for BusyBox. Without these, |
| * huge chunks of ram are pre-allocated making the BusyBox bss |
| * size Freaking Huge(tm), which is a bad thing.*/ |
| #define SMALL_MEM |
| #define DYN_ALLOC |
| |
| #define BB_DECLARE_EXTERN |
| #define bb_need_memory_exhausted |
| #define bb_need_name_too_long |
| #include "messages.c" |
| |
| |
| /* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface |
| * Copyright (C) 1992-1993 Jean-loup Gailly |
| * The unzip code was written and put in the public domain by Mark Adler. |
| * Portions of the lzw code are derived from the public domain 'compress' |
| * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies, |
| * Ken Turkowski, Dave Mack and Peter Jannesen. |
| * |
| * See the license_msg below and the file COPYING for the software license. |
| * See the file algorithm.doc for the compression algorithms and file formats. |
| */ |
| |
| #if 0 |
| static char *license_msg[] = { |
| " Copyright (C) 1992-1993 Jean-loup Gailly", |
| " This program is free software; you can redistribute it and/or modify", |
| " it under the terms of the GNU General Public License as published by", |
| " the Free Software Foundation; either version 2, or (at your option)", |
| " any later version.", |
| "", |
| " This program is distributed in the hope that it will be useful,", |
| " but WITHOUT ANY WARRANTY; without even the implied warranty of", |
| " MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the", |
| " GNU General Public License for more details.", |
| "", |
| " You should have received a copy of the GNU General Public License", |
| " along with this program; if not, write to the Free Software", |
| " Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.", |
| 0 |
| }; |
| #endif |
| |
| /* Compress files with zip algorithm and 'compress' interface. |
| * See usage() and help() functions below for all options. |
| * Outputs: |
| * file.gz: compressed file with same mode, owner, and utimes |
| * or stdout with -c option or if stdin used as input. |
| * If the output file name had to be truncated, the original name is kept |
| * in the compressed file. |
| * On MSDOS, file.tmp -> file.tmz. On VMS, file.tmp -> file.tmp-gz. |
| * |
| * Using gz on MSDOS would create too many file name conflicts. For |
| * example, foo.txt -> foo.tgz (.tgz must be reserved as shorthand for |
| * tar.gz). Similarly, foo.dir and foo.doc would both be mapped to foo.dgz. |
| * I also considered 12345678.txt -> 12345txt.gz but this truncates the name |
| * too heavily. There is no ideal solution given the MSDOS 8+3 limitation. |
| * |
| * For the meaning of all compilation flags, see comments in Makefile.in. |
| */ |
| |
| #include <ctype.h> |
| #include <sys/types.h> |
| #include <signal.h> |
| #include <sys/stat.h> |
| #include <errno.h> |
| |
| /* #include "tailor.h" */ |
| |
| /* tailor.h -- target dependent definitions |
| * Copyright (C) 1992-1993 Jean-loup Gailly. |
| * This is free software; you can redistribute it and/or modify it under the |
| * terms of the GNU General Public License, see the file COPYING. |
| */ |
| |
| /* The target dependent definitions should be defined here only. |
| * The target dependent functions should be defined in tailor.c. |
| */ |
| |
| #define RECORD_IO 0 |
| |
| #define get_char() get_byte() |
| #define put_char(c) put_byte(c) |
| |
| |
| /* I don't like nested includes, but the string and io functions are used |
| * too often |
| */ |
| #include <stdio.h> |
| #if !defined(NO_STRING_H) || defined(STDC_HEADERS) |
| # include <string.h> |
| # if !defined(STDC_HEADERS) && !defined(NO_MEMORY_H) && !defined(__GNUC__) |
| # include <memory.h> |
| # endif |
| # define memzero(s, n) memset ((void *)(s), 0, (n)) |
| #else |
| # include <strings.h> |
| # define strchr index |
| # define strrchr rindex |
| # define memcpy(d, s, n) bcopy((s), (d), (n)) |
| # define memcmp(s1, s2, n) bcmp((s1), (s2), (n)) |
| # define memzero(s, n) bzero((s), (n)) |
| #endif |
| |
| #ifndef RETSIGTYPE |
| # define RETSIGTYPE void |
| #endif |
| |
| #define local static |
| |
| typedef unsigned char uch; |
| typedef unsigned short ush; |
| typedef unsigned long ulg; |
| |
| /* Return codes from gzip */ |
| #define OK 0 |
| #define ERROR 1 |
| #define WARNING 2 |
| |
| /* Compression methods (see algorithm.doc) */ |
| #define DEFLATED 8 |
| |
| extern int method; /* compression method */ |
| |
| /* To save memory for 16 bit systems, some arrays are overlaid between |
| * the various modules: |
| * deflate: prev+head window d_buf l_buf outbuf |
| * unlzw: tab_prefix tab_suffix stack inbuf outbuf |
| * inflate: window inbuf |
| * unpack: window inbuf prefix_len |
| * unlzh: left+right window c_table inbuf c_len |
| * For compression, input is done in window[]. For decompression, output |
| * is done in window except for unlzw. |
| */ |
| |
| #ifndef INBUFSIZ |
| # ifdef SMALL_MEM |
| # define INBUFSIZ 0x2000 /* input buffer size */ |
| # else |
| # define INBUFSIZ 0x8000 /* input buffer size */ |
| # endif |
| #endif |
| #define INBUF_EXTRA 64 /* required by unlzw() */ |
| |
| #ifndef OUTBUFSIZ |
| # ifdef SMALL_MEM |
| # define OUTBUFSIZ 8192 /* output buffer size */ |
| # else |
| # define OUTBUFSIZ 16384 /* output buffer size */ |
| # endif |
| #endif |
| #define OUTBUF_EXTRA 2048 /* required by unlzw() */ |
| |
| #define SMALL_MEM |
| |
| #ifndef DIST_BUFSIZE |
| # ifdef SMALL_MEM |
| # define DIST_BUFSIZE 0x2000 /* buffer for distances, see trees.c */ |
| # else |
| # define DIST_BUFSIZE 0x8000 /* buffer for distances, see trees.c */ |
| # endif |
| #endif |
| |
| /*#define DYN_ALLOC*/ |
| |
| #ifdef DYN_ALLOC |
| # define EXTERN(type, array) extern type * array |
| # define DECLARE(type, array, size) type * array |
| # define ALLOC(type, array, size) { \ |
| array = (type*)calloc((size_t)(((size)+1L)/2), 2*sizeof(type)); \ |
| if (array == NULL) errorMsg(memory_exhausted); \ |
| } |
| # define FREE(array) {if (array != NULL) free(array), array=NULL;} |
| #else |
| # define EXTERN(type, array) extern type array[] |
| # define DECLARE(type, array, size) type array[size] |
| # define ALLOC(type, array, size) |
| # define FREE(array) |
| #endif |
| |
| EXTERN(uch, inbuf); /* input buffer */ |
| EXTERN(uch, outbuf); /* output buffer */ |
| EXTERN(ush, d_buf); /* buffer for distances, see trees.c */ |
| EXTERN(uch, window); /* Sliding window and suffix table (unlzw) */ |
| #define tab_suffix window |
| #ifndef MAXSEG_64K |
| # define tab_prefix prev /* hash link (see deflate.c) */ |
| # define head (prev+WSIZE) /* hash head (see deflate.c) */ |
| EXTERN(ush, tab_prefix); /* prefix code (see unlzw.c) */ |
| #else |
| # define tab_prefix0 prev |
| # define head tab_prefix1 |
| EXTERN(ush, tab_prefix0); /* prefix for even codes */ |
| EXTERN(ush, tab_prefix1); /* prefix for odd codes */ |
| #endif |
| |
| extern unsigned insize; /* valid bytes in inbuf */ |
| extern unsigned inptr; /* index of next byte to be processed in inbuf */ |
| extern unsigned outcnt; /* bytes in output buffer */ |
| |
| extern long bytes_in; /* number of input bytes */ |
| extern long bytes_out; /* number of output bytes */ |
| extern long header_bytes; /* number of bytes in gzip header */ |
| |
| extern long ifile_size; /* input file size, -1 for devices (debug only) */ |
| |
| typedef int file_t; /* Do not use stdio */ |
| |
| #define NO_FILE (-1) /* in memory compression */ |
| |
| |
| #define GZIP_MAGIC "\037\213" /* Magic header for gzip files, 1F 8B */ |
| |
| /* gzip flag byte */ |
| #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ |
| #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ |
| #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 ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ |
| #define RESERVED 0xC0 /* bit 6,7: reserved */ |
| |
| #ifndef WSIZE |
| # define WSIZE 0x8000 /* window size--must be a power of two, and */ |
| #endif /* at least 32K for zip's deflate method */ |
| |
| #define MIN_MATCH 3 |
| #define MAX_MATCH 258 |
| /* The minimum and maximum match lengths */ |
| |
| #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 (WSIZE-MIN_LOOKAHEAD) |
| /* In order to simplify the code, particularly on 16 bit machines, match |
| * distances are limited to MAX_DIST instead of WSIZE. |
| */ |
| |
| extern int exit_code; /* program exit code */ |
| extern int verbose; /* be verbose (-v) */ |
| extern int level; /* compression level */ |
| extern int test; /* check .z file integrity */ |
| extern int save_orig_name; /* set if original name must be saved */ |
| |
| #define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf(0)) |
| #define try_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf(1)) |
| |
| /* put_byte is used for the compressed output, put_ubyte for the |
| * uncompressed output. However unlzw() uses window for its |
| * suffix table instead of its output buffer, so it does not use put_ubyte |
| * (to be cleaned up). |
| */ |
| #define put_byte(c) {outbuf[outcnt++]=(uch)(c); if (outcnt==OUTBUFSIZ)\ |
| flush_outbuf();} |
| #define put_ubyte(c) {window[outcnt++]=(uch)(c); if (outcnt==WSIZE)\ |
| flush_window();} |
| |
| /* Output a 16 bit value, lsb first */ |
| #define put_short(w) \ |
| { if (outcnt < OUTBUFSIZ-2) { \ |
| outbuf[outcnt++] = (uch) ((w) & 0xff); \ |
| outbuf[outcnt++] = (uch) ((ush)(w) >> 8); \ |
| } else { \ |
| put_byte((uch)((w) & 0xff)); \ |
| put_byte((uch)((ush)(w) >> 8)); \ |
| } \ |
| } |
| |
| /* Output a 32 bit value to the bit stream, lsb first */ |
| #define put_long(n) { \ |
| put_short((n) & 0xffff); \ |
| put_short(((ulg)(n)) >> 16); \ |
| } |
| |
| #define seekable() 0 /* force sequential output */ |
| #define translate_eol 0 /* no option -a yet */ |
| |
| #define tolow(c) (isupper(c) ? (c)-'A'+'a' : (c)) /* force to lower case */ |
| |
| /* Macros for getting two-byte and four-byte header values */ |
| #define SH(p) ((ush)(uch)((p)[0]) | ((ush)(uch)((p)[1]) << 8)) |
| #define LG(p) ((ulg)(SH(p)) | ((ulg)(SH((p)+2)) << 16)) |
| |
| /* Diagnostic functions */ |
| #ifdef DEBUG |
| # define Assert(cond,msg) {if(!(cond)) errorMsg(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 |
| |
| #define WARN(msg) {fprintf msg ; \ |
| if (exit_code == OK) exit_code = WARNING;} |
| |
| /* in unzip.c */ |
| extern int unzip (int in, int out); |
| |
| /* in gzip.c */ |
| RETSIGTYPE abort_gzip (void); |
| |
| /* in deflate.c */ |
| void lm_init (int pack_level, ush * flags); |
| ulg deflate (void); |
| |
| /* in trees.c */ |
| void ct_init (ush * attr, int *method); |
| int ct_tally (int dist, int lc); |
| ulg flush_block (char *buf, ulg stored_len, int eof); |
| |
| /* in bits.c */ |
| void bi_init (file_t zipfile); |
| void send_bits (int value, int length); |
| unsigned bi_reverse (unsigned value, int length); |
| void bi_windup (void); |
| void copy_block (char *buf, unsigned len, int header); |
| |
| /* in util.c: */ |
| extern ulg updcrc (uch * s, unsigned n); |
| extern void clear_bufs (void); |
| static int fill_inbuf (int eof_ok); |
| extern void flush_outbuf (void); |
| static void flush_window (void); |
| extern void write_buf (int fd, void * buf, unsigned cnt); |
| |
| #ifndef __linux__ |
| static char *basename (char *fname); |
| #endif /* not __linux__ */ |
| void read_error_msg (void); |
| void write_error_msg (void); |
| |
| /* in inflate.c */ |
| static int inflate (void); |
| |
| /* #include "lzw.h" */ |
| |
| /* lzw.h -- define the lzw functions. |
| * Copyright (C) 1992-1993 Jean-loup Gailly. |
| * This is free software; you can redistribute it and/or modify it under the |
| * terms of the GNU General Public License, see the file COPYING. |
| */ |
| |
| #if !defined(OF) && defined(lint) |
| # include "gzip.h" |
| #endif |
| |
| #ifndef BITS |
| # define BITS 16 |
| #endif |
| #define INIT_BITS 9 /* Initial number of bits per code */ |
| |
| #define LZW_MAGIC "\037\235" /* Magic header for lzw files, 1F 9D */ |
| |
| #define BIT_MASK 0x1f /* Mask for 'number of compression bits' */ |
| /* Mask 0x20 is reserved to mean a fourth header byte, and 0x40 is free. |
| * It's a pity that old uncompress does not check bit 0x20. That makes |
| * extension of the format actually undesirable because old compress |
| * would just crash on the new format instead of giving a meaningful |
| * error message. It does check the number of bits, but it's more |
| * helpful to say "unsupported format, get a new version" than |
| * "can only handle 16 bits". |
| */ |
| |
| #define BLOCK_MODE 0x80 |
| /* Block compression: if table is full and compression rate is dropping, |
| * clear the dictionary. |
| */ |
| |
| #define LZW_RESERVED 0x60 /* reserved bits */ |
| |
| #define CLEAR 256 /* flush the dictionary */ |
| #define FIRST (CLEAR+1) /* first free entry */ |
| |
| extern int maxbits; /* max bits per code for LZW */ |
| extern int block_mode; /* block compress mode -C compatible with 2.0 */ |
| |
| extern int lzw (int in, int out); |
| extern int unlzw (int in, int out); |
| |
| |
| /* #include "revision.h" */ |
| |
| /* revision.h -- define the version number |
| * Copyright (C) 1992-1993 Jean-loup Gailly. |
| * This is free software; you can redistribute it and/or modify it under the |
| * terms of the GNU General Public License, see the file COPYING. |
| */ |
| |
| #define VERSION "1.2.4" |
| #define PATCHLEVEL 0 |
| #define REVDATE "18 Aug 93" |
| |
| /* This version does not support compression into old compress format: */ |
| #ifdef LZW |
| # undef LZW |
| #endif |
| |
| #include <time.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #if defined(DIRENT) |
| # include <dirent.h> |
| typedef struct dirent dir_type; |
| |
| # define NLENGTH(dirent) ((int)strlen((dirent)->d_name)) |
| # define DIR_OPT "DIRENT" |
| #else |
| # define NLENGTH(dirent) ((dirent)->d_namlen) |
| # ifdef SYSDIR |
| # include <sys/dir.h> |
| typedef struct direct dir_type; |
| |
| # define DIR_OPT "SYSDIR" |
| # else |
| # ifdef SYSNDIR |
| # include <sys/ndir.h> |
| typedef struct direct dir_type; |
| |
| # define DIR_OPT "SYSNDIR" |
| # else |
| # ifdef NDIR |
| # include <ndir.h> |
| typedef struct direct dir_type; |
| |
| # define DIR_OPT "NDIR" |
| # else |
| # define NO_DIR |
| # define DIR_OPT "NO_DIR" |
| # endif |
| # endif |
| # endif |
| #endif |
| #if !defined(S_ISDIR) && defined(S_IFDIR) |
| # define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR) |
| #endif |
| #if !defined(S_ISREG) && defined(S_IFREG) |
| # define S_ISREG(m) (((m) & S_IFMT) == S_IFREG) |
| #endif |
| typedef RETSIGTYPE(*sig_type) (int); |
| |
| #ifndef O_BINARY |
| # define O_BINARY 0 /* creation mode for open() */ |
| #endif |
| |
| #ifndef O_CREAT |
| /* Pure BSD system? */ |
| # include <sys/file.h> |
| # ifndef O_CREAT |
| # define O_CREAT FCREAT |
| # endif |
| # ifndef O_EXCL |
| # define O_EXCL FEXCL |
| # endif |
| #endif |
| |
| #ifndef S_IRUSR |
| # define S_IRUSR 0400 |
| #endif |
| #ifndef S_IWUSR |
| # define S_IWUSR 0200 |
| #endif |
| #define RW_USER (S_IRUSR | S_IWUSR) /* creation mode for open() */ |
| |
| #ifndef MAX_PATH_LEN /* max pathname length */ |
| # ifdef BUFSIZ |
| # define MAX_PATH_LEN BUFSIZ |
| # else |
| # define MAX_PATH_LEN 1024 |
| # endif |
| #endif |
| |
| #ifndef SEEK_END |
| # define SEEK_END 2 |
| #endif |
| |
| #ifdef NO_OFF_T |
| typedef long off_t; |
| off_t lseek (int fd, off_t offset, int whence); |
| #endif |
| |
| |
| /* global buffers */ |
| |
| DECLARE(uch, inbuf, INBUFSIZ + INBUF_EXTRA); |
| DECLARE(uch, outbuf, OUTBUFSIZ + OUTBUF_EXTRA); |
| DECLARE(ush, d_buf, DIST_BUFSIZE); |
| DECLARE(uch, window, 2L * WSIZE); |
| #ifndef MAXSEG_64K |
| DECLARE(ush, tab_prefix, 1L << BITS); |
| #else |
| DECLARE(ush, tab_prefix0, 1L << (BITS - 1)); |
| DECLARE(ush, tab_prefix1, 1L << (BITS - 1)); |
| #endif |
| |
| /* local variables */ |
| |
| int test_mode = 0; /* check file integrity option */ |
| int foreground; /* set if program run in foreground */ |
| int maxbits = BITS; /* max bits per code for LZW */ |
| int method = DEFLATED; /* compression method */ |
| int exit_code = OK; /* program exit code */ |
| int last_member; /* set for .zip and .Z files */ |
| int part_nb; /* number of parts in .gz file */ |
| long ifile_size; /* input file size, -1 for devices (debug only) */ |
| |
| long bytes_in; /* number of input bytes */ |
| long bytes_out; /* number of output bytes */ |
| long total_in = 0; /* input bytes for all files */ |
| long total_out = 0; /* output bytes for all files */ |
| struct stat istat; /* status for input file */ |
| int ifd; /* input file descriptor */ |
| int ofd; /* output file descriptor */ |
| unsigned insize; /* valid bytes in inbuf */ |
| unsigned inptr; /* index of next byte to be processed in inbuf */ |
| unsigned outcnt; /* bytes in output buffer */ |
| |
| long header_bytes; /* number of bytes in gzip header */ |
| |
| /* local functions */ |
| |
| local int get_method (int in); |
| |
| #define strequ(s1, s2) (strcmp((s1),(s2)) == 0) |
| |
| /* ======================================================================== */ |
| int gunzip_main(int argc, char **argv) |
| { |
| int file_count; /* number of files to precess */ |
| int tostdout = 0; |
| int fromstdin = 0; |
| int result; |
| int inFileNum; |
| int outFileNum; |
| int delInputFile = 0; |
| int force = 0; |
| struct stat statBuf; |
| char *delFileName; |
| char ifname[MAX_PATH_LEN + 1]; /* input file name */ |
| char ofname[MAX_PATH_LEN + 1]; /* output file name */ |
| |
| if (strcmp(applet_name, "zcat") == 0) { |
| tostdout = 1; |
| if (argc == 1) { |
| fromstdin = 1; |
| } |
| } |
| |
| /* Parse any options */ |
| while (--argc > 0 && **(++argv) == '-') { |
| if (*((*argv) + 1) == '\0') { |
| tostdout = 1; |
| } |
| while (*(++(*argv))) { |
| switch (**argv) { |
| case 'c': |
| tostdout = 1; |
| break; |
| case 't': |
| test_mode = 1; |
| break; |
| case 'f': |
| force = 1; |
| break; |
| default: |
| usage(gunzip_usage); |
| } |
| } |
| } |
| if (argc <= 0) |
| fromstdin = 1; |
| |
| if (isatty(fileno(stdin)) && fromstdin==1 && force==0) |
| fatalError( "data not read from terminal. Use -f to force it.\n"); |
| if (isatty(fileno(stdout)) && tostdout==1 && force==0) |
| fatalError( "data not written to terminal. Use -f to force it.\n"); |
| |
| |
| foreground = signal(SIGINT, SIG_IGN) != SIG_IGN; |
| if (foreground) { |
| (void) signal(SIGINT, (sig_type) abort_gzip); |
| } |
| #ifdef SIGTERM |
| if (signal(SIGTERM, SIG_IGN) != SIG_IGN) { |
| (void) signal(SIGTERM, (sig_type) abort_gzip); |
| } |
| #endif |
| #ifdef SIGHUP |
| if (signal(SIGHUP, SIG_IGN) != SIG_IGN) { |
| (void) signal(SIGHUP, (sig_type) abort_gzip); |
| } |
| #endif |
| |
| file_count = argc - optind; |
| |
| /* Allocate all global buffers (for DYN_ALLOC option) */ |
| ALLOC(uch, inbuf, INBUFSIZ + INBUF_EXTRA); |
| ALLOC(uch, outbuf, OUTBUFSIZ + OUTBUF_EXTRA); |
| ALLOC(ush, d_buf, DIST_BUFSIZE); |
| ALLOC(uch, window, 2L * WSIZE); |
| #ifndef MAXSEG_64K |
| ALLOC(ush, tab_prefix, 1L << BITS); |
| #else |
| ALLOC(ush, tab_prefix0, 1L << (BITS - 1)); |
| ALLOC(ush, tab_prefix1, 1L << (BITS - 1)); |
| #endif |
| |
| if (fromstdin == 1) { |
| strcpy(ofname, "stdin"); |
| |
| inFileNum = fileno(stdin); |
| ifile_size = -1L; /* convention for unknown size */ |
| } else { |
| /* Open up the input file */ |
| if (argc <= 0) |
| usage(gunzip_usage); |
| if (strlen(*argv) > MAX_PATH_LEN) { |
| errorMsg(name_too_long); |
| exit(WARNING); |
| } |
| strcpy(ifname, *argv); |
| |
| /* Open input fille */ |
| inFileNum = open(ifname, O_RDONLY); |
| if (inFileNum < 0) { |
| perror(ifname); |
| exit(WARNING); |
| } |
| /* Get the time stamp on the input file. */ |
| result = stat(ifname, &statBuf); |
| if (result < 0) { |
| perror(ifname); |
| exit(WARNING); |
| } |
| ifile_size = statBuf.st_size; |
| } |
| |
| if (tostdout == 1) { |
| /* And get to work */ |
| strcpy(ofname, "stdout"); |
| outFileNum = fileno(stdout); |
| |
| clear_bufs(); /* clear input and output buffers */ |
| part_nb = 0; |
| |
| /* Actually do the compression/decompression. */ |
| unzip(inFileNum, outFileNum); |
| |
| } else if (test_mode) { |
| /* Actually do the compression/decompression. */ |
| unzip(inFileNum, 2); |
| } else { |
| char *pos; |
| |
| /* And get to work */ |
| if (strlen(ifname) > MAX_PATH_LEN - 4) { |
| errorMsg(name_too_long); |
| exit(WARNING); |
| } |
| strcpy(ofname, ifname); |
| pos = strstr(ofname, ".gz"); |
| if (pos != NULL) { |
| *pos = '\0'; |
| delInputFile = 1; |
| } else { |
| pos = strstr(ofname, ".tgz"); |
| if (pos != NULL) { |
| *pos = '\0'; |
| strcat(pos, ".tar"); |
| delInputFile = 1; |
| } |
| } |
| |
| /* Open output fille */ |
| #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1) |
| outFileNum = open(ofname, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW); |
| #else |
| outFileNum = open(ofname, O_RDWR | O_CREAT | O_EXCL); |
| #endif |
| if (outFileNum < 0) { |
| perror(ofname); |
| exit(WARNING); |
| } |
| /* Set permissions on the file */ |
| fchmod(outFileNum, statBuf.st_mode); |
| |
| clear_bufs(); /* clear input and output buffers */ |
| part_nb = 0; |
| |
| /* Actually do the compression/decompression. */ |
| result = unzip(inFileNum, outFileNum); |
| |
| close(outFileNum); |
| close(inFileNum); |
| /* Delete the original file */ |
| if (result == OK) |
| delFileName = ifname; |
| else |
| delFileName = ofname; |
| |
| if (delInputFile == 1 && unlink(delFileName) < 0) { |
| perror(delFileName); |
| exit(FALSE); |
| } |
| } |
| return(exit_code); |
| } |
| |
| |
| /* ======================================================================== |
| * Check the magic number of the input file and update ofname if an |
| * original name was given and tostdout is not set. |
| * Return the compression method, -1 for error, -2 for warning. |
| * Set inptr to the offset of the next byte to be processed. |
| * Updates time_stamp if there is one and --no-time is not used. |
| * This function may be called repeatedly for an input file consisting |
| * of several contiguous gzip'ed members. |
| * IN assertions: there is at least one remaining compressed member. |
| * If the member is a zip file, it must be the only one. |
| */ |
| local int get_method(in) |
| int in; /* input file descriptor */ |
| { |
| uch flags; /* compression flags */ |
| char magic[2]; /* magic header */ |
| |
| magic[0] = (char) get_byte(); |
| magic[1] = (char) get_byte(); |
| method = -1; /* unknown yet */ |
| part_nb++; /* number of parts in gzip file */ |
| header_bytes = 0; |
| last_member = RECORD_IO; |
| /* assume multiple members in gzip file except for record oriented I/O */ |
| |
| if (memcmp(magic, GZIP_MAGIC, 2) == 0) { |
| |
| method = (int) get_byte(); |
| if (method != DEFLATED) { |
| errorMsg("unknown method %d -- get newer version of gzip\n", |
| method); |
| exit_code = ERROR; |
| return -1; |
| } |
| flags = (uch) get_byte(); |
| |
| (ulg) get_byte(); /* Ignore time stamp */ |
| (ulg) get_byte(); |
| (ulg) get_byte(); |
| (ulg) get_byte(); |
| |
| (void) get_byte(); /* Ignore extra flags for the moment */ |
| (void) get_byte(); /* Ignore OS type for the moment */ |
| |
| if ((flags & EXTRA_FIELD) != 0) { |
| unsigned len = (unsigned) get_byte(); |
| |
| len |= ((unsigned) get_byte()) << 8; |
| |
| while (len--) |
| (void) get_byte(); |
| } |
| |
| /* Discard original name if any */ |
| if ((flags & ORIG_NAME) != 0) { |
| while (get_char() != 0) /* null */ |
| ; |
| } |
| |
| /* Discard file comment if any */ |
| if ((flags & COMMENT) != 0) { |
| while (get_char() != 0) /* null */ |
| ; |
| } |
| if (part_nb == 1) { |
| header_bytes = inptr + 2 * sizeof(long); /* include crc and size */ |
| } |
| |
| } |
| |
| if (method >= 0) |
| return method; |
| |
| if (part_nb == 1) { |
| fprintf(stderr, "\nnot in gzip format\n"); |
| exit_code = ERROR; |
| return -1; |
| } else { |
| WARN((stderr, "\ndecompression OK, trailing garbage ignored\n")); |
| return -2; |
| } |
| } |
| |
| /* ======================================================================== |
| * Signal and error handler. |
| */ |
| RETSIGTYPE abort_gzip() |
| { |
| exit(ERROR); |
| } |
| |
| /* unzip.c -- decompress files in gzip or pkzip format. |
| * Copyright (C) 1992-1993 Jean-loup Gailly |
| * This is free software; you can redistribute it and/or modify it under the |
| * terms of the GNU General Public License, see the file COPYING. |
| * |
| * The code in this file is derived from the file funzip.c written |
| * and put in the public domain by Mark Adler. |
| */ |
| |
| /* |
| This version can extract files in gzip or pkzip format. |
| For the latter, only the first entry is extracted, and it has to be |
| either deflated or stored. |
| */ |
| |
| /* #include "crypt.h" */ |
| |
| /* crypt.h (dummy version) -- do not perform encryption |
| * Hardly worth copyrighting :-) |
| */ |
| |
| #ifdef CRYPT |
| # undef CRYPT /* dummy version */ |
| #endif |
| |
| #define RAND_HEAD_LEN 12 /* length of encryption random header */ |
| |
| #define zencode |
| #define zdecode |
| |
| /* PKZIP header definitions */ |
| #define LOCSIG 0x04034b50L /* four-byte lead-in (lsb first) */ |
| #define LOCFLG 6 /* offset of bit flag */ |
| #define CRPFLG 1 /* bit for encrypted entry */ |
| #define EXTFLG 8 /* bit for extended local header */ |
| #define LOCHOW 8 /* offset of compression method */ |
| #define LOCTIM 10 /* file mod time (for decryption) */ |
| #define LOCCRC 14 /* offset of crc */ |
| #define LOCSIZ 18 /* offset of compressed size */ |
| #define LOCLEN 22 /* offset of uncompressed length */ |
| #define LOCFIL 26 /* offset of file name field length */ |
| #define LOCEXT 28 /* offset of extra field length */ |
| #define LOCHDR 30 /* size of local header, including sig */ |
| #define EXTHDR 16 /* size of extended local header, inc sig */ |
| |
| |
| /* Globals */ |
| |
| char *key; /* not used--needed to link crypt.c */ |
| int pkzip = 0; /* set for a pkzip file */ |
| int ext_header = 0; /* set if extended local header */ |
| |
| /* =========================================================================== |
| * Unzip in to out. This routine works on both gzip and pkzip files. |
| * |
| * IN assertions: the buffer inbuf contains already the beginning of |
| * the compressed data, from offsets inptr to insize-1 included. |
| * The magic header has already been checked. The output buffer is cleared. |
| */ |
| int unzip(in, out) |
| int in, out; /* input and output file descriptors */ |
| { |
| ulg orig_crc = 0; /* original crc */ |
| ulg orig_len = 0; /* original uncompressed length */ |
| int n; |
| uch buf[EXTHDR]; /* extended local header */ |
| |
| ifd = in; |
| ofd = out; |
| method = get_method(ifd); |
| if (method < 0) { |
| exit(exit_code); /* error message already emitted */ |
| } |
| |
| updcrc(NULL, 0); /* initialize crc */ |
| |
| if (pkzip && !ext_header) { /* crc and length at the end otherwise */ |
| orig_crc = LG(inbuf + LOCCRC); |
| orig_len = LG(inbuf + LOCLEN); |
| } |
| |
| /* Decompress */ |
| if (method == DEFLATED) { |
| |
| int res = inflate(); |
| |
| if (res == 3) { |
| errorMsg(memory_exhausted); |
| } else if (res != 0) { |
| errorMsg("invalid compressed data--format violated"); |
| } |
| |
| } else { |
| errorMsg("internal error, invalid method"); |
| } |
| |
| /* Get the crc and original length */ |
| if (!pkzip) { |
| /* crc32 (see algorithm.doc) |
| * uncompressed input size modulo 2^32 |
| */ |
| for (n = 0; n < 8; n++) { |
| buf[n] = (uch) get_byte(); /* may cause an error if EOF */ |
| } |
| orig_crc = LG(buf); |
| orig_len = LG(buf + 4); |
| |
| } else if (ext_header) { /* If extended header, check it */ |
| /* signature - 4bytes: 0x50 0x4b 0x07 0x08 |
| * CRC-32 value |
| * compressed size 4-bytes |
| * uncompressed size 4-bytes |
| */ |
| for (n = 0; n < EXTHDR; n++) { |
| buf[n] = (uch) get_byte(); /* may cause an error if EOF */ |
| } |
| orig_crc = LG(buf + 4); |
| orig_len = LG(buf + 12); |
| } |
| |
| /* Validate decompression */ |
| if (orig_crc != updcrc(outbuf, 0)) { |
| errorMsg("invalid compressed data--crc error"); |
| } |
| if (orig_len != (ulg) bytes_out) { |
| errorMsg("invalid compressed data--length error"); |
| } |
| |
| /* Check if there are more entries in a pkzip file */ |
| if (pkzip && inptr + 4 < insize && LG(inbuf + inptr) == LOCSIG) { |
| WARN((stderr, "has more than one entry--rest ignored\n")); |
| } |
| ext_header = pkzip = 0; /* for next file */ |
| return OK; |
| } |
| |
| /* util.c -- utility functions for gzip support |
| * Copyright (C) 1992-1993 Jean-loup Gailly |
| * This is free software; you can redistribute it and/or modify it under the |
| * terms of the GNU General Public License, see the file COPYING. |
| */ |
| |
| #include <ctype.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| |
| #ifdef HAVE_UNISTD_H |
| # include <unistd.h> |
| #endif |
| #ifndef NO_FCNTL_H |
| # include <fcntl.h> |
| #endif |
| |
| #if defined(STDC_HEADERS) || !defined(NO_STDLIB_H) |
| # include <stdlib.h> |
| #else |
| extern int errno; |
| #endif |
| |
| static const ulg crc_32_tab[]; /* crc table, defined below */ |
| |
| /* =========================================================================== |
| * Run a set of bytes through the crc shift register. If s is a NULL |
| * pointer, then initialize the crc shift register contents instead. |
| * Return the current crc in either case. |
| */ |
| ulg updcrc(s, n) |
| uch *s; /* pointer to bytes to pump through */ |
| unsigned n; /* number of bytes in s[] */ |
| { |
| register ulg c; /* temporary variable */ |
| |
| static ulg crc = (ulg) 0xffffffffL; /* shift register contents */ |
| |
| if (s == NULL) { |
| c = 0xffffffffL; |
| } else { |
| c = crc; |
| if (n) |
| do { |
| c = crc_32_tab[((int) c ^ (*s++)) & 0xff] ^ (c >> 8); |
| } while (--n); |
| } |
| crc = c; |
| return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */ |
| } |
| |
| /* =========================================================================== |
| * Clear input and output buffers |
| */ |
| void clear_bufs(void) |
| { |
| outcnt = 0; |
| insize = inptr = 0; |
| bytes_in = bytes_out = 0L; |
| } |
| |
| /* =========================================================================== |
| * Fill the input buffer. This is called only when the buffer is empty. |
| */ |
| int fill_inbuf(eof_ok) |
| int eof_ok; /* set if EOF acceptable as a result */ |
| { |
| int len; |
| |
| /* Read as much as possible */ |
| insize = 0; |
| errno = 0; |
| do { |
| len = read(ifd, (char *) inbuf + insize, INBUFSIZ - insize); |
| if (len == 0 || len == EOF) |
| break; |
| insize += len; |
| } while (insize < INBUFSIZ); |
| |
| if (insize == 0) { |
| if (eof_ok) |
| return EOF; |
| read_error_msg(); |
| } |
| bytes_in += (ulg) insize; |
| inptr = 1; |
| return inbuf[0]; |
| } |
| |
| /* =========================================================================== |
| * Write the output buffer outbuf[0..outcnt-1] and update bytes_out. |
| * (used for the compressed data only) |
| */ |
| void flush_outbuf() |
| { |
| if (outcnt == 0) |
| return; |
| |
| if (!test_mode) |
| write_buf(ofd, (char *) outbuf, outcnt); |
| bytes_out += (ulg) outcnt; |
| outcnt = 0; |
| } |
| |
| /* =========================================================================== |
| * Write the output window window[0..outcnt-1] and update crc and bytes_out. |
| * (Used for the decompressed data only.) |
| */ |
| void flush_window() |
| { |
| if (outcnt == 0) |
| return; |
| updcrc(window, outcnt); |
| |
| if (!test_mode) |
| write_buf(ofd, (char *) window, outcnt); |
| bytes_out += (ulg) outcnt; |
| outcnt = 0; |
| } |
| |
| /* =========================================================================== |
| * Does the same as write(), but also handles partial pipe writes and checks |
| * for error return. |
| */ |
| void write_buf(fd, buf, cnt) |
| int fd; |
| void * buf; |
| unsigned cnt; |
| { |
| unsigned n; |
| |
| while ((n = write(fd, buf, cnt)) != cnt) { |
| if (n == (unsigned) (-1)) { |
| write_error_msg(); |
| } |
| cnt -= n; |
| buf = (void *) ((char *) buf + n); |
| } |
| } |
| |
| #if defined(NO_STRING_H) && !defined(STDC_HEADERS) |
| |
| /* Provide missing strspn and strcspn functions. */ |
| |
| # ifndef __STDC__ |
| # define const |
| # endif |
| |
| int strspn (const char *s, const char *accept); |
| int strcspn (const char *s, const char *reject); |
| |
| /* ======================================================================== |
| * Return the length of the maximum initial segment |
| * of s which contains only characters in accept. |
| */ |
| int strspn(s, accept) |
| const char *s; |
| const char *accept; |
| { |
| register const char *p; |
| register const char *a; |
| register int count = 0; |
| |
| for (p = s; *p != '\0'; ++p) { |
| for (a = accept; *a != '\0'; ++a) { |
| if (*p == *a) |
| break; |
| } |
| if (*a == '\0') |
| return count; |
| ++count; |
| } |
| return count; |
| } |
| |
| /* ======================================================================== |
| * Return the length of the maximum inital segment of s |
| * which contains no characters from reject. |
| */ |
| int strcspn(s, reject) |
| const char *s; |
| const char *reject; |
| { |
| register int count = 0; |
| |
| while (*s != '\0') { |
| if (strchr(reject, *s++) != NULL) |
| return count; |
| ++count; |
| } |
| return count; |
| } |
| |
| #endif /* NO_STRING_H */ |
| |
| |
| /* ======================================================================== |
| * Error handlers. |
| */ |
| void read_error_msg() |
| { |
| fprintf(stderr, "\n"); |
| if (errno != 0) { |
| perror(""); |
| } else { |
| fprintf(stderr, "unexpected end of file\n"); |
| } |
| abort_gzip(); |
| } |
| |
| void write_error_msg() |
| { |
| fprintf(stderr, "\n"); |
| perror(""); |
| abort_gzip(); |
| } |
| |
| |
| /* ======================================================================== |
| * Table of CRC-32's of all single-byte values (made by makecrc.c) |
| */ |
| static const ulg crc_32_tab[] = { |
| 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 |
| }; |
| |
| /* inflate.c -- Not copyrighted 1992 by Mark Adler |
| version c10p1, 10 January 1993 */ |
| |
| /* You can do whatever you like with this source file, though I would |
| prefer that if you modify it and redistribute it that you include |
| comments to that effect with your name and the date. Thank you. |
| [The history has been moved to the file ChangeLog.] |
| */ |
| |
| /* |
| Inflate deflated (PKZIP's method 8 compressed) data. The compression |
| method searches for as much of the current string of bytes (up to a |
| length of 258) in the previous 32K bytes. If it doesn't find any |
| matches (of at least length 3), it codes the next byte. Otherwise, it |
| codes the length of the matched string and its distance backwards from |
| the current position. There is a single Huffman code that codes both |
| single bytes (called "literals") and match lengths. A second Huffman |
| code codes the distance information, which follows a length code. Each |
| length or distance code actually represents a base value and a number |
| of "extra" (sometimes zero) bits to get to add to the base value. At |
| the end of each deflated block is a special end-of-block (EOB) literal/ |
| length code. The decoding process is basically: get a literal/length |
| code; if EOB then done; if a literal, emit the decoded byte; if a |
| length then get the distance and emit the referred-to bytes from the |
| sliding window of previously emitted data. |
| |
| There are (currently) three kinds of inflate blocks: stored, fixed, and |
| dynamic. The compressor deals with some chunk of data at a time, and |
| decides which method to use on a chunk-by-chunk basis. A chunk might |
| typically be 32K or 64K. If the chunk is uncompressible, then the |
| "stored" method is used. In this case, the bytes are simply stored as |
| is, eight bits per byte, with none of the above coding. The bytes are |
| preceded by a count, since there is no longer an EOB code. |
| |
| If the data is compressible, then either the fixed or dynamic methods |
| are used. In the dynamic method, the compressed data is preceded by |
| an encoding of the literal/length and distance Huffman codes that are |
| to be used to decode this block. The representation is itself Huffman |
| coded, and so is preceded by a description of that code. These code |
| descriptions take up a little space, and so for small blocks, there is |
| a predefined set of codes, called the fixed codes. The fixed method is |
| used if the block codes up smaller that way (usually for quite small |
| chunks), otherwise the dynamic method is used. In the latter case, the |
| codes are customized to the probabilities in the current block, and so |
| can code it much better than the pre-determined fixed codes. |
| |
| The Huffman codes themselves are decoded using a mutli-level table |
| lookup, in order to maximize the speed of decoding plus the speed of |
| building the decoding tables. See the comments below that precede the |
| lbits and dbits tuning parameters. |
| */ |
| |
| |
| /* |
| 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. Similarly, 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. |
| */ |
| |
| #include <sys/types.h> |
| |
| #if defined(STDC_HEADERS) || !defined(NO_STDLIB_H) |
| # include <stdlib.h> |
| #endif |
| |
| |
| #define slide window |
| |
| /* 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 are 0..13. e == 15 is EOB (end of block), e == 16 |
| means that v is a literal, 16 < e < 32 means that v is a pointer to |
| the next table, which codes e - 16 bits, and lastly e == 99 indicates |
| an unused code. If a code with e == 99 is looked up, this implies an |
| error in the data. */ |
| struct huft { |
| uch e; /* number of extra bits or operation */ |
| uch b; /* number of bits in this code or subcode */ |
| union { |
| ush n; /* literal, length base, or distance base */ |
| struct huft *t; /* pointer to next level of table */ |
| } v; |
| }; |
| |
| |
| /* Function prototypes */ |
| int huft_build (unsigned *, unsigned, unsigned, ush *, ush *, |
| struct huft **, int *); |
| int huft_free (struct huft *); |
| int inflate_codes (struct huft *, struct huft *, int, int); |
| int inflate_stored (void); |
| int inflate_fixed (void); |
| int inflate_dynamic (void); |
| int inflate_block (int *); |
| int inflate (void); |
| |
| |
| /* The inflate algorithm uses a sliding 32K byte window on the uncompressed |
| stream to find repeated byte strings. This is implemented here as a |
| circular buffer. The index is updated simply by incrementing and then |
| and'ing with 0x7fff (32K-1). */ |
| /* It is left to other modules to supply the 32K area. It is assumed |
| to be usable as if it were declared "uch slide[32768];" or as just |
| "uch *slide;" and then malloc'ed in the latter case. The definition |
| must be in unzip.h, included above. */ |
| /* unsigned wp; current position in slide */ |
| #define wp outcnt |
| #define flush_output(w) (wp=(w),flush_window()) |
| |
| /* Tables for deflate from PKZIP's appnote.txt. */ |
| static unsigned 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 |
| }; |
| static ush 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 |
| }; |
| |
| /* note: see note #13 above about the 258 in this list. */ |
| static ush 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, 99, 99 |
| }; /* 99==invalid */ |
| static ush 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 |
| }; |
| static ush 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 |
| }; |
| |
| |
| |
| /* Macros for inflate() bit peeking and grabbing. |
| The usage is: |
| |
| NEEDBITS(j) |
| x = b & mask_bits[j]; |
| DUMPBITS(j) |
| |
| where NEEDBITS makes sure that b has at least j bits in it, and |
| DUMPBITS removes the bits from b. The macros use the variable k |
| for the number of bits in b. Normally, b and k are register |
| variables for speed, and are initialized at the beginning of a |
| routine that uses these macros from a global bit buffer and count. |
| |
| If we assume that EOB will be the longest code, then we will never |
| ask for bits with NEEDBITS that are beyond the end of the stream. |
| So, NEEDBITS should not read any more bytes than are needed to |
| meet the request. Then no bytes need to be "returned" to the buffer |
| at the end of the last block. |
| |
| However, this assumption is not true for fixed blocks--the EOB code |
| is 7 bits, but the other literal/length codes can be 8 or 9 bits. |
| (The EOB code is shorter than other codes because fixed blocks are |
| generally short. So, while a block always has an EOB, many other |
| literal/length codes have a significantly lower probability of |
| showing up at all.) However, by making the first table have a |
| lookup of seven bits, the EOB code will be found in that first |
| lookup, and so will not require that too many bits be pulled from |
| the stream. |
| */ |
| |
| ulg bb; /* bit buffer */ |
| unsigned bk; /* bits in bit buffer */ |
| |
| ush mask_bits[] = { |
| 0x0000, |
| 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, |
| 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff |
| }; |
| |
| #ifdef CRYPT |
| uch cc; |
| |
| # define NEXTBYTE() (cc = get_byte(), zdecode(cc), cc) |
| #else |
| # define NEXTBYTE() (uch)get_byte() |
| #endif |
| #define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}} |
| #define DUMPBITS(n) {b>>=(n);k-=(n);} |
| |
| |
| /* |
| 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. |
| */ |
| |
| |
| int lbits = 9; /* bits in base literal/length lookup table */ |
| int dbits = 6; /* bits in base distance lookup table */ |
| |
| |
| /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */ |
| #define BMAX 16 /* maximum bit length of any code (16 for explode) */ |
| #define N_MAX 288 /* maximum number of codes in any set */ |
| |
| |
| unsigned hufts; /* track memory usage */ |
| |
| |
| int huft_build(b, n, s, d, e, t, m) |
| unsigned *b; /* code lengths in bits (all assumed <= BMAX) */ |
| unsigned n; /* number of codes (assumed <= N_MAX) */ |
| unsigned s; /* number of simple-valued codes (0..s-1) */ |
| ush *d; /* list of base values for non-simple codes */ |
| ush *e; /* list of extra bits for non-simple codes */ |
| struct huft **t; /* result: starting table */ |
| int *m; /* maximum lookup bits, returns actual */ |
| |
| /* Given a list of code lengths and a maximum table size, make a set of |
| tables to decode that set of codes. Return zero on success, one if |
| the given code set is incomplete (the tables are still built in this |
| case), two if the input is invalid (all zero length codes or an |
| oversubscribed set of lengths), and three if not enough memory. */ |
| { |
| unsigned a; /* counter for codes of length k */ |
| unsigned c[BMAX + 1]; /* bit length count table */ |
| unsigned f; /* i repeats in table every f entries */ |
| int g; /* maximum code length */ |
| int h; /* table level */ |
| register unsigned i; /* counter, current code */ |
| register unsigned j; /* counter */ |
| register int k; /* number of bits in current code */ |
| int l; /* bits per table (returned in m) */ |
| register unsigned *p; /* pointer into c[], b[], or v[] */ |
| register struct huft *q; /* points to current table */ |
| struct huft r; /* table entry for structure assignment */ |
| struct huft *u[BMAX]; /* table stack */ |
| unsigned v[N_MAX]; /* values in order of bit length */ |
| register int w; /* bits before this table == (l * h) */ |
| unsigned x[BMAX + 1]; /* bit offsets, then code stack */ |
| unsigned *xp; /* pointer into x */ |
| int y; /* number of dummy codes added */ |
| unsigned z; /* number of entries in current table */ |
| |
| |
| /* Generate counts for each bit length */ |
| memzero(c, sizeof(c)); |
| p = b; |
| i = n; |
| do { |
| Tracecv(*p, |
| (stderr, |
| (n - i >= ' ' |
| && n - i <= '~' ? "%c %d\n" : "0x%x %d\n"), n - i, *p)); |
| c[*p]++; /* assume all entries <= BMAX */ |
| p++; /* Can't combine with above line (Solaris bug) */ |
| } while (--i); |
| if (c[0] == n) { /* null input--all zero length codes */ |
| *t = (struct huft *) NULL; |
| *m = 0; |
| return 0; |
| } |
| |
| |
| /* 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 ((unsigned) l < j) |
| l = j; |
| for (i = BMAX; i; i--) |
| if (c[i]) |
| break; |
| g = i; /* maximum code length */ |
| if ((unsigned) 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 2; /* bad input: more codes than bits */ |
| if ((y -= c[i]) < 0) |
| return 2; |
| 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] = (struct huft *) NULL; /* just to keep compilers happy */ |
| q = (struct huft *) 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) > (unsigned) l ? l : z; /* upper limit on table size */ |
| 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; |
| 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 = |
| (struct huft *) malloc((z + 1) * |
| sizeof(struct huft))) == |
| (struct huft *) NULL) { |
| if (h) |
| huft_free(u[0]); |
| return 3; /* not enough memory */ |
| } |
| hufts += z + 1; /* track memory usage */ |
| *t = q + 1; /* link to list for huft_free() */ |
| *(t = &(q->v.t)) = (struct huft *) 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.b = (uch) l; /* bits to dump before this table */ |
| r.e = (uch) (16 + j); /* bits in this table */ |
| r.v.t = 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.b = (uch) (k - w); |
| if (p >= v + n) |
| r.e = 99; /* out of values--invalid code */ |
| else if (*p < s) { |
| r.e = (uch) (*p < 256 ? 16 : 15); /* 256 is end-of-block code */ |
| r.v.n = (ush) (*p); /* simple code is just the value */ |
| p++; /* one compiler does not like *p++ */ |
| } else { |
| r.e = (uch) e[*p - s]; /* non-simple--look up in lists */ |
| r.v.n = 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 true (1) if we were given an incomplete table */ |
| return y != 0 && g != 1; |
| } |
| |
| |
| |
| int huft_free(t) |
| struct huft *t; /* table to free */ |
| |
| /* 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 struct huft *p, *q; |
| |
| |
| /* Go through linked list, freeing from the malloced (t[-1]) address. */ |
| p = t; |
| while (p != (struct huft *) NULL) { |
| q = (--p)->v.t; |
| free((char *) p); |
| p = q; |
| } |
| return 0; |
| } |
| |
| |
| int inflate_codes(tl, td, bl, bd) |
| struct huft *tl, *td; /* literal/length and distance decoder tables */ |
| int bl, bd; /* number of bits decoded by tl[] and td[] */ |
| |
| /* inflate (decompress) the codes in a deflated (compressed) block. |
| Return an error code or zero if it all goes ok. */ |
| { |
| register unsigned e; /* table entry flag/number of extra bits */ |
| unsigned n, d; /* length and index for copy */ |
| unsigned w; /* current window position */ |
| struct huft *t; /* pointer to table entry */ |
| unsigned ml, md; /* masks for bl and bd bits */ |
| register ulg b; /* bit buffer */ |
| register unsigned k; /* number of bits in bit buffer */ |
| |
| |
| /* make local copies of globals */ |
| b = bb; /* initialize bit buffer */ |
| k = bk; |
| w = wp; /* initialize window position */ |
| |
| /* inflate the coded data */ |
| ml = mask_bits[bl]; /* precompute masks for speed */ |
| md = mask_bits[bd]; |
| for (;;) { /* do until end of block */ |
| NEEDBITS((unsigned) bl) |
| if ((e = (t = tl + ((unsigned) b & ml))->e) > 16) |
| do { |
| if (e == 99) |
| return 1; |
| DUMPBITS(t->b) |
| e -= 16; |
| NEEDBITS(e) |
| } while ((e = (t = t->v.t + ((unsigned) b & mask_bits[e]))->e) |
| > 16); |
| DUMPBITS(t->b) |
| if (e == 16) { /* then it's a literal */ |
| slide[w++] = (uch) t->v.n; |
| Tracevv((stderr, "%c", slide[w - 1])); |
| if (w == WSIZE) { |
| flush_output(w); |
| w = 0; |
| } |
| } else { /* it's an EOB or a length */ |
| |
| /* exit if end of block */ |
| if (e == 15) |
| break; |
| |
| /* get length of block to copy */ |
| NEEDBITS(e) |
| n = t->v.n + ((unsigned) b & mask_bits[e]); |
| DUMPBITS(e); |
| |
| /* decode distance of block to copy */ |
| NEEDBITS((unsigned) bd) |
| if ((e = (t = td + ((unsigned) b & md))->e) > 16) |
| do { |
| if (e == 99) |
| return 1; |
| DUMPBITS(t->b) |
| e -= 16; |
| NEEDBITS(e) |
| } |
| while ( |
| (e = |
| (t = |
| t->v.t + ((unsigned) b & mask_bits[e]))->e) > |
| 16); |
| DUMPBITS(t->b) |
| NEEDBITS(e) |
| d = w - t->v.n - ((unsigned) b & mask_bits[e]); |
| DUMPBITS(e) |
| Tracevv((stderr, "\\[%d,%d]", w - d, n)); |
| |
| /* do the copy */ |
| do { |
| n -= (e = |
| (e = |
| WSIZE - ((d &= WSIZE - 1) > w ? d : w)) > |
| n ? n : e); |
| #if !defined(NOMEMCPY) && !defined(DEBUG) |
| if (w - d >= e) { /* (this test assumes unsigned comparison) */ |
| memcpy(slide + w, slide + d, e); |
| w += e; |
| d += e; |
| } else /* do it slow to avoid memcpy() overlap */ |
| #endif /* !NOMEMCPY */ |
| do { |
| slide[w++] = slide[d++]; |
| Tracevv((stderr, "%c", slide[w - 1])); |
| } while (--e); |
| if (w == WSIZE) { |
| flush_output(w); |
| w = 0; |
| } |
| } while (n); |
| } |
| } |
| |
| |
| /* restore the globals from the locals */ |
| wp = w; /* restore global window pointer */ |
| bb = b; /* restore global bit buffer */ |
| bk = k; |
| |
| /* done */ |
| return 0; |
| } |
| |
| |
| |
| int inflate_stored() |
| /* "decompress" an inflated type 0 (stored) block. */ |
| { |
| unsigned n; /* number of bytes in block */ |
| unsigned w; /* current window position */ |
| register ulg b; /* bit buffer */ |
| register unsigned k; /* number of bits in bit buffer */ |
| |
| |
| /* make local copies of globals */ |
| b = bb; /* initialize bit buffer */ |
| k = bk; |
| w = wp; /* initialize window position */ |
| |
| |
| /* go to byte boundary */ |
| n = k & 7; |
| DUMPBITS(n); |
| |
| |
| /* get the length and its complement */ |
| NEEDBITS(16) |
| n = ((unsigned) b & 0xffff); |
| DUMPBITS(16) |
| NEEDBITS(16) |
| if (n != (unsigned) ((~b) & 0xffff)) |
| return 1; /* error in compressed data */ |
| DUMPBITS(16) |
| |
| |
| /* read and output the compressed data */ |
| while (n--) { |
| NEEDBITS(8) |
| slide[w++] = (uch) b; |
| if (w == WSIZE) { |
| flush_output(w); |
| w = 0; |
| } |
| DUMPBITS(8) |
| } |
| |
| |
| /* restore the globals from the locals */ |
| wp = w; /* restore global window pointer */ |
| bb = b; /* restore global bit buffer */ |
| bk = k; |
| return 0; |
| } |
| |
| |
| |
| int inflate_fixed() |
| /* decompress an inflated type 1 (fixed Huffman codes) block. We should |
| either replace this with a custom decoder, or at least precompute the |
| Huffman tables. */ |
| { |
| int i; /* temporary variable */ |
| struct huft *tl; /* literal/length code table */ |
| struct huft *td; /* distance code table */ |
| int bl; /* lookup bits for tl */ |
| int bd; /* lookup bits for td */ |
| unsigned l[288]; /* length list for huft_build */ |
| |
| |
| /* set up literal table */ |
| for (i = 0; i < 144; i++) |
| l[i] = 8; |
| for (; i < 256; i++) |
| l[i] = 9; |
| for (; i < 280; i++) |
| l[i] = 7; |
| for (; i < 288; i++) /* make a complete, but wrong code set */ |
| l[i] = 8; |
| bl = 7; |
| if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0) |
| return i; |
| |
| |
| /* set up distance table */ |
| for (i = 0; i < 30; i++) /* make an incomplete code set */ |
| l[i] = 5; |
| bd = 5; |
| if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1) { |
| huft_free(tl); |
| return i; |
| } |
| |
| |
| /* decompress until an end-of-block code */ |
| if (inflate_codes(tl, td, bl, bd)) |
| return 1; |
| |
| |
| /* free the decoding tables, return */ |
| huft_free(tl); |
| huft_free(td); |
| return 0; |
| } |
| |
| |
| |
| int inflate_dynamic() |
| /* decompress an inflated type 2 (dynamic Huffman codes) block. */ |
| { |
| int i; /* temporary variables */ |
| unsigned j; |
| unsigned l; /* last length */ |
| unsigned m; /* mask for bit lengths table */ |
| unsigned n; /* number of lengths to get */ |
| struct huft *tl; /* literal/length code table */ |
| struct huft *td; /* distance code table */ |
| int bl; /* lookup bits for tl */ |
| int bd; /* lookup bits for td */ |
| unsigned nb; /* number of bit length codes */ |
| unsigned nl; /* number of literal/length codes */ |
| unsigned nd; /* number of distance codes */ |
| |
| #ifdef PKZIP_BUG_WORKAROUND |
| unsigned ll[288 + 32]; /* literal/length and distance code lengths */ |
| #else |
| unsigned ll[286 + 30]; /* literal/length and distance code lengths */ |
| #endif |
| register ulg b; /* bit buffer */ |
| register unsigned k; /* number of bits in bit buffer */ |
| |
| |
| /* make local bit buffer */ |
| b = bb; |
| k = bk; |
| |
| |
| /* read in table lengths */ |
| NEEDBITS(5) |
| nl = 257 + ((unsigned) b & 0x1f); /* number of literal/length codes */ |
| DUMPBITS(5) |
| NEEDBITS(5) |
| nd = 1 + ((unsigned) b & 0x1f); /* number of distance codes */ |
| DUMPBITS(5) |
| NEEDBITS(4) |
| nb = 4 + ((unsigned) b & 0xf); /* number of bit length codes */ |
| DUMPBITS(4) |
| #ifdef PKZIP_BUG_WORKAROUND |
| if (nl > 288 || nd > 32) |
| #else |
| if (nl > 286 || nd > 30) |
| #endif |
| return 1; /* bad lengths */ |
| |
| |
| /* read in bit-length-code lengths */ |
| for (j = 0; j < nb; j++) { |
| NEEDBITS(3) |
| ll[border[j]] = (unsigned) b & 7; |
| DUMPBITS(3) |
| } |
| for (; j < 19; j++) |
| ll[border[j]] = 0; |
| |
| |
| /* build decoding table for trees--single level, 7 bit lookup */ |
| bl = 7; |
| if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0) { |
| if (i == 1) |
| huft_free(tl); |
| return i; /* incomplete code set */ |
| } |
| |
| |
| /* read in literal and distance code lengths */ |
| n = nl + nd; |
| m = mask_bits[bl]; |
| i = l = 0; |
| while ((unsigned) i < n) { |
| NEEDBITS((unsigned) bl) |
| j = (td = tl + ((unsigned) b & m))->b; |
| DUMPBITS(j) |
| j = td->v.n; |
| if (j < 16) /* length of code in bits (0..15) */ |
| ll[i++] = l = j; /* save last length in l */ |
| else if (j == 16) { /* repeat last length 3 to 6 times */ |
| NEEDBITS(2) |
| j = 3 + ((unsigned) b & 3); |
| DUMPBITS(2) |
| if ((unsigned) i + j > n) |
| return 1; |
| while (j--) |
| ll[i++] = l; |
| } else if (j == 17) { /* 3 to 10 zero length codes */ |
| NEEDBITS(3) |
| j = 3 + ((unsigned) b & 7); |
| DUMPBITS(3) |
| if ((unsigned) i + j > n) |
| return 1; |
| while (j--) |
| ll[i++] = 0; |
| l = 0; |
| } else { /* j == 18: 11 to 138 zero length codes */ |
| |
| NEEDBITS(7) |
| j = 11 + ((unsigned) b & 0x7f); |
| DUMPBITS(7) |
| if ((unsigned) i + j > n) |
| return 1; |
| while (j--) |
| ll[i++] = 0; |
| l = 0; |
| } |
| } |
| |
| |
| /* free decoding table for trees */ |
| huft_free(tl); |
| |
| |
| /* restore the global bit buffer */ |
| bb = b; |
| bk = k; |
| |
| |
| /* build the decoding tables for literal/length and distance codes */ |
| bl = lbits; |
| if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0) { |
| if (i == 1) { |
| fprintf(stderr, " incomplete literal tree\n"); |
| huft_free(tl); |
| } |
| return i; /* incomplete code set */ |
| } |
| bd = dbits; |
| if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0) { |
| if (i == 1) { |
| fprintf(stderr, " incomplete distance tree\n"); |
| #ifdef PKZIP_BUG_WORKAROUND |
| i = 0; |
| } |
| #else |
| huft_free(td); |
| } |
| huft_free(tl); |
| return i; /* incomplete code set */ |
| #endif |
| } |
| |
| |
| /* decompress until an end-of-block code */ |
| if (inflate_codes(tl, td, bl, bd)) |
| return 1; |
| |
| |
| /* free the decoding tables, return */ |
| huft_free(tl); |
| huft_free(td); |
| return 0; |
| } |
| |
| |
| |
| int inflate_block(e) |
| int *e; /* last block flag */ |
| |
| /* decompress an inflated block */ |
| { |
| unsigned t; /* block type */ |
| register ulg b; /* bit buffer */ |
| register unsigned k; /* number of bits in bit buffer */ |
| |
| |
| /* make local bit buffer */ |
| b = bb; |
| k = bk; |
| |
| |
| /* read in last block bit */ |
| NEEDBITS(1) |
| * e = (int) b & 1; |
| DUMPBITS(1) |
| |
| |
| /* read in block type */ |
| NEEDBITS(2) |
| t = (unsigned) b & 3; |
| DUMPBITS(2) |
| |
| |
| /* restore the global bit buffer */ |
| bb = b; |
| bk = k; |
| |
| |
| /* inflate that block type */ |
| if (t == 2) |
| return inflate_dynamic(); |
| if (t == 0) |
| return inflate_stored(); |
| if (t == 1) |
| return inflate_fixed(); |
| |
| |
| /* bad block type */ |
| return 2; |
| } |
| |
| |
| |
| int inflate() |
| /* decompress an inflated entry */ |
| { |
| int e; /* last block flag */ |
| int r; /* result code */ |
| unsigned h; /* maximum struct huft's malloc'ed */ |
| |
| |
| /* initialize window, bit buffer */ |
| wp = 0; |
| bk = 0; |
| bb = 0; |
| |
| |
| /* decompress until the last block */ |
| h = 0; |
| do { |
| hufts = 0; |
| if ((r = inflate_block(&e)) != 0) |
| return r; |
| if (hufts > h) |
| h = hufts; |
| } while (!e); |
| |
| /* Undo too much lookahead. The next read will be byte aligned so we |
| * can discard unused bits in the last meaningful byte. |
| */ |
| while (bk >= 8) { |
| bk -= 8; |
| inptr--; |
| } |
| |
| /* flush out slide */ |
| flush_output(wp); |
| |
| |
| /* return success */ |
| #ifdef DEBUG |
| fprintf(stderr, "<%u> ", h); |
| #endif /* DEBUG */ |
| return 0; |
| } |