1 /* zcat : stripped version based on gzip sources
2 Sven Rudolph <sr1@inf.tu-dresden.de>
7 static const char zcat_usage[] = "zcat\n"
9 "\tuncompress gzipped data from stdin to stdout\n";
13 /* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
14 * Copyright (C) 1992-1993 Jean-loup Gailly
15 * The unzip code was written and put in the public domain by Mark Adler.
16 * Portions of the lzw code are derived from the public domain 'compress'
17 * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
18 * Ken Turkowski, Dave Mack and Peter Jannesen.
20 * See the license_msg below and the file COPYING for the software license.
21 * See the file algorithm.doc for the compression algorithms and file formats.
25 static char *license_msg[] = {
26 " Copyright (C) 1992-1993 Jean-loup Gailly",
27 " This program is free software; you can redistribute it and/or modify",
28 " it under the terms of the GNU General Public License as published by",
29 " the Free Software Foundation; either version 2, or (at your option)",
30 " any later version.",
32 " This program is distributed in the hope that it will be useful,",
33 " but WITHOUT ANY WARRANTY; without even the implied warranty of",
34 " MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the",
35 " GNU General Public License for more details.",
37 " You should have received a copy of the GNU General Public License",
38 " along with this program; if not, write to the Free Software",
39 " Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.",
43 /* Compress files with zip algorithm and 'compress' interface.
44 * See usage() and help() functions below for all options.
46 * file.gz: compressed file with same mode, owner, and utimes
47 * or stdout with -c option or if stdin used as input.
48 * If the output file name had to be truncated, the original name is kept
49 * in the compressed file.
50 * On MSDOS, file.tmp -> file.tmz. On VMS, file.tmp -> file.tmp-gz.
52 * Using gz on MSDOS would create too many file name conflicts. For
53 * example, foo.txt -> foo.tgz (.tgz must be reserved as shorthand for
54 * tar.gz). Similarly, foo.dir and foo.doc would both be mapped to foo.dgz.
55 * I also considered 12345678.txt -> 12345txt.gz but this truncates the name
56 * too heavily. There is no ideal solution given the MSDOS 8+3 limitation.
58 * For the meaning of all compilation flags, see comments in Makefile.in.
62 static char rcsid[] = "$Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $";
66 #include <sys/types.h>
71 /* #include "tailor.h" */
73 /* tailor.h -- target dependent definitions
74 * Copyright (C) 1992-1993 Jean-loup Gailly.
75 * This is free software; you can redistribute it and/or modify it under the
76 * terms of the GNU General Public License, see the file COPYING.
79 /* The target dependent definitions should be defined here only.
80 * The target dependent functions should be defined in tailor.c.
83 /* $Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $ */
87 #define get_char() get_byte()
88 #define put_char(c) put_byte(c)
90 /* #include "gzip.h" */
92 /* gzip.h -- common declarations for all gzip modules
93 * Copyright (C) 1992-1993 Jean-loup Gailly.
94 * This is free software; you can redistribute it and/or modify it under the
95 * terms of the GNU General Public License, see the file COPYING.
98 #if defined(__STDC__) || defined(PROTO)
99 # define OF(args) args
110 /* I don't like nested includes, but the string and io functions are used
114 #if !defined(NO_STRING_H) || defined(STDC_HEADERS)
116 # if !defined(STDC_HEADERS) && !defined(NO_MEMORY_H) && !defined(__GNUC__)
119 # define memzero(s, n) memset ((voidp)(s), 0, (n))
121 # include <strings.h>
122 # define strchr index
123 # define strrchr rindex
124 # define memcpy(d, s, n) bcopy((s), (d), (n))
125 # define memcmp(s1, s2, n) bcmp((s1), (s2), (n))
126 # define memzero(s, n) bzero((s), (n))
130 # define RETSIGTYPE void
135 typedef unsigned char uch;
136 typedef unsigned short ush;
137 typedef unsigned long ulg;
139 /* Return codes from gzip */
144 /* Compression methods (see algorithm.doc) */
147 extern int method; /* compression method */
149 /* To save memory for 16 bit systems, some arrays are overlaid between
150 * the various modules:
151 * deflate: prev+head window d_buf l_buf outbuf
152 * unlzw: tab_prefix tab_suffix stack inbuf outbuf
153 * inflate: window inbuf
154 * unpack: window inbuf prefix_len
155 * unlzh: left+right window c_table inbuf c_len
156 * For compression, input is done in window[]. For decompression, output
157 * is done in window except for unlzw.
162 # define INBUFSIZ 0x2000 /* input buffer size */
164 # define INBUFSIZ 0x8000 /* input buffer size */
167 #define INBUF_EXTRA 64 /* required by unlzw() */
171 # define OUTBUFSIZ 8192 /* output buffer size */
173 # define OUTBUFSIZ 16384 /* output buffer size */
176 #define OUTBUF_EXTRA 2048 /* required by unlzw() */
182 # define DIST_BUFSIZE 0x2000 /* buffer for distances, see trees.c */
184 # define DIST_BUFSIZE 0x8000 /* buffer for distances, see trees.c */
188 /*#define DYN_ALLOC*/
191 # define EXTERN(type, array) extern type * array
192 # define DECLARE(type, array, size) type * array
193 # define ALLOC(type, array, size) { \
194 array = (type*)calloc((size_t)(((size)+1L)/2), 2*sizeof(type)); \
195 if (array == NULL) error("insufficient memory"); \
197 # define FREE(array) {if (array != NULL) free(array), array=NULL;}
199 # define EXTERN(type, array) extern type array[]
200 # define DECLARE(type, array, size) type array[size]
201 # define ALLOC(type, array, size)
205 EXTERN(uch, inbuf); /* input buffer */
206 EXTERN(uch, outbuf); /* output buffer */
207 EXTERN(ush, d_buf); /* buffer for distances, see trees.c */
208 EXTERN(uch, window); /* Sliding window and suffix table (unlzw) */
209 #define tab_suffix window
211 # define tab_prefix prev /* hash link (see deflate.c) */
212 # define head (prev+WSIZE) /* hash head (see deflate.c) */
213 EXTERN(ush, tab_prefix); /* prefix code (see unlzw.c) */
215 # define tab_prefix0 prev
216 # define head tab_prefix1
217 EXTERN(ush, tab_prefix0); /* prefix for even codes */
218 EXTERN(ush, tab_prefix1); /* prefix for odd codes */
221 extern unsigned insize; /* valid bytes in inbuf */
222 extern unsigned inptr; /* index of next byte to be processed in inbuf */
223 extern unsigned outcnt; /* bytes in output buffer */
225 extern long bytes_in; /* number of input bytes */
226 extern long bytes_out; /* number of output bytes */
227 extern long header_bytes;/* number of bytes in gzip header */
229 extern int ifd; /* input file descriptor */
230 extern int ofd; /* output file descriptor */
232 extern long ifile_size; /* input file size, -1 for devices (debug only) */
234 typedef int file_t; /* Do not use stdio */
235 #define NO_FILE (-1) /* in memory compression */
238 #define GZIP_MAGIC "\037\213" /* Magic header for gzip files, 1F 8B */
241 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
242 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
243 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
244 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
245 #define COMMENT 0x10 /* bit 4 set: file comment present */
246 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
247 #define RESERVED 0xC0 /* bit 6,7: reserved */
250 # define WSIZE 0x8000 /* window size--must be a power of two, and */
251 #endif /* at least 32K for zip's deflate method */
254 #define MAX_MATCH 258
255 /* The minimum and maximum match lengths */
257 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
258 /* Minimum amount of lookahead, except at the end of the input file.
259 * See deflate.c for comments about the MIN_MATCH+1.
262 #define MAX_DIST (WSIZE-MIN_LOOKAHEAD)
263 /* In order to simplify the code, particularly on 16 bit machines, match
264 * distances are limited to MAX_DIST instead of WSIZE.
267 extern int exit_code; /* program exit code */
268 extern int verbose; /* be verbose (-v) */
269 extern int level; /* compression level */
270 extern int test; /* check .z file integrity */
271 extern int to_stdout; /* output to stdout (-c) */
272 extern int save_orig_name; /* set if original name must be saved */
274 #define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf(0))
275 #define try_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf(1))
277 /* put_byte is used for the compressed output, put_ubyte for the
278 * uncompressed output. However unlzw() uses window for its
279 * suffix table instead of its output buffer, so it does not use put_ubyte
280 * (to be cleaned up).
282 #define put_byte(c) {outbuf[outcnt++]=(uch)(c); if (outcnt==OUTBUFSIZ)\
284 #define put_ubyte(c) {window[outcnt++]=(uch)(c); if (outcnt==WSIZE)\
287 /* Output a 16 bit value, lsb first */
288 #define put_short(w) \
289 { if (outcnt < OUTBUFSIZ-2) { \
290 outbuf[outcnt++] = (uch) ((w) & 0xff); \
291 outbuf[outcnt++] = (uch) ((ush)(w) >> 8); \
293 put_byte((uch)((w) & 0xff)); \
294 put_byte((uch)((ush)(w) >> 8)); \
298 /* Output a 32 bit value to the bit stream, lsb first */
299 #define put_long(n) { \
300 put_short((n) & 0xffff); \
301 put_short(((ulg)(n)) >> 16); \
304 #define seekable() 0 /* force sequential output */
305 #define translate_eol 0 /* no option -a yet */
307 #define tolow(c) (isupper(c) ? (c)-'A'+'a' : (c)) /* force to lower case */
309 /* Macros for getting two-byte and four-byte header values */
310 #define SH(p) ((ush)(uch)((p)[0]) | ((ush)(uch)((p)[1]) << 8))
311 #define LG(p) ((ulg)(SH(p)) | ((ulg)(SH((p)+2)) << 16))
313 /* Diagnostic functions */
315 # define Assert(cond,msg) {if(!(cond)) error(msg);}
316 # define Trace(x) fprintf x
317 # define Tracev(x) {if (verbose) fprintf x ;}
318 # define Tracevv(x) {if (verbose>1) fprintf x ;}
319 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
320 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
322 # define Assert(cond,msg)
327 # define Tracecv(c,x)
330 #define WARN(msg) {fprintf msg ; \
331 if (exit_code == OK) exit_code = WARNING;}
334 extern int unzip OF((int in, int out));
337 RETSIGTYPE abort_gzip OF((void));
340 void lm_init OF((int pack_level, ush *flags));
341 ulg deflate OF((void));
344 void ct_init OF((ush *attr, int *method));
345 int ct_tally OF((int dist, int lc));
346 ulg flush_block OF((char *buf, ulg stored_len, int eof));
349 void bi_init OF((file_t zipfile));
350 void send_bits OF((int value, int length));
351 unsigned bi_reverse OF((unsigned value, int length));
352 void bi_windup OF((void));
353 void copy_block OF((char *buf, unsigned len, int header));
354 extern int (*read_buf) OF((char *buf, unsigned size));
357 extern int copy OF((int in, int out));
358 extern ulg updcrc OF((uch *s, unsigned n));
359 extern void clear_bufs OF((void));
360 extern int fill_inbuf OF((int eof_ok));
361 extern void flush_outbuf OF((void));
362 extern void flush_window OF((void));
363 extern void write_buf OF((int fd, voidp buf, unsigned cnt));
365 extern char *basename OF((char *fname));
366 #endif /* not __linux__ */
367 extern void error OF((char *m));
368 extern void warn OF((char *a, char *b));
369 extern void read_error OF((void));
370 extern void write_error OF((void));
371 extern voidp xmalloc OF((unsigned int size));
374 extern int inflate OF((void));
376 /* #include "lzw.h" */
378 /* lzw.h -- define the lzw functions.
379 * Copyright (C) 1992-1993 Jean-loup Gailly.
380 * This is free software; you can redistribute it and/or modify it under the
381 * terms of the GNU General Public License, see the file COPYING.
384 #if !defined(OF) && defined(lint)
391 #define INIT_BITS 9 /* Initial number of bits per code */
393 #define LZW_MAGIC "\037\235" /* Magic header for lzw files, 1F 9D */
395 #define BIT_MASK 0x1f /* Mask for 'number of compression bits' */
396 /* Mask 0x20 is reserved to mean a fourth header byte, and 0x40 is free.
397 * It's a pity that old uncompress does not check bit 0x20. That makes
398 * extension of the format actually undesirable because old compress
399 * would just crash on the new format instead of giving a meaningful
400 * error message. It does check the number of bits, but it's more
401 * helpful to say "unsupported format, get a new version" than
402 * "can only handle 16 bits".
405 #define BLOCK_MODE 0x80
406 /* Block compression: if table is full and compression rate is dropping,
407 * clear the dictionary.
410 #define LZW_RESERVED 0x60 /* reserved bits */
412 #define CLEAR 256 /* flush the dictionary */
413 #define FIRST (CLEAR+1) /* first free entry */
415 extern int maxbits; /* max bits per code for LZW */
416 extern int block_mode; /* block compress mode -C compatible with 2.0 */
418 extern int lzw OF((int in, int out));
419 extern int unlzw OF((int in, int out));
422 /* #include "revision.h" */
424 /* revision.h -- define the version number
425 * Copyright (C) 1992-1993 Jean-loup Gailly.
426 * This is free software; you can redistribute it and/or modify it under the
427 * terms of the GNU General Public License, see the file COPYING.
430 #define VERSION "1.2.4"
432 #define REVDATE "18 Aug 93"
434 /* This version does not support compression into old compress format: */
439 /* $Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $ */
441 /* #include "getopt.h" */
443 /* Declarations for getopt.
444 Copyright (C) 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
446 This program is free software; you can redistribute it and/or modify it
447 under the terms of the GNU General Public License as published by the
448 Free Software Foundation; either version 2, or (at your option) any
451 This program is distributed in the hope that it will be useful,
452 but WITHOUT ANY WARRANTY; without even the implied warranty of
453 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
454 GNU General Public License for more details.
456 You should have received a copy of the GNU General Public License
457 along with this program; if not, write to the Free Software
458 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
467 /* For communication from `getopt' to the caller.
468 When `getopt' finds an option that takes an argument,
469 the argument value is returned here.
470 Also, when `ordering' is RETURN_IN_ORDER,
471 each non-option ARGV-element is returned here. */
475 /* Index in ARGV of the next element to be scanned.
476 This is used for communication to and from the caller
477 and for communication between successive calls to `getopt'.
479 On entry to `getopt', zero means this is the first call; initialize.
481 When `getopt' returns EOF, this is the index of the first of the
482 non-option elements that the caller should itself scan.
484 Otherwise, `optind' communicates from one call to the next
485 how much of ARGV has been scanned so far. */
489 /* Callers store zero here to inhibit the error message `getopt' prints
490 for unrecognized options. */
494 /* Set to an option character which was unrecognized. */
498 /* Describe the long-named options requested by the application.
499 The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
500 of `struct option' terminated by an element containing a name which is
503 The field `has_arg' is:
504 no_argument (or 0) if the option does not take an argument,
505 required_argument (or 1) if the option requires an argument,
506 optional_argument (or 2) if the option takes an optional argument.
508 If the field `flag' is not NULL, it points to a variable that is set
509 to the value given in the field `val' when the option is found, but
510 left unchanged if the option is not found.
512 To have a long-named option do something other than set an `int' to
513 a compiled-in constant, such as set a value from `optarg', set the
514 option's `flag' field to zero and its `val' field to a nonzero
515 value (the equivalent single-letter option character, if there is
516 one). For long options that have a zero `flag' field, `getopt'
517 returns the contents of the `val' field. */
526 /* has_arg can't be an enum because some compilers complain about
527 type mismatches in all the code that assumes it is an int. */
533 /* Names for the values of the `has_arg' field of `struct option'. */
535 #define no_argument 0
536 #define required_argument 1
537 #define optional_argument 2
539 #if __STDC__ || defined(PROTO)
540 #if defined(__GNU_LIBRARY__)
541 /* Many other libraries have conflicting prototypes for getopt, with
542 differences in the consts, in stdlib.h. To avoid compilation
543 errors, only prototype getopt for the GNU C library. */
544 extern int getopt (int argc, char *const *argv, const char *shortopts);
545 #endif /* not __GNU_LIBRARY__ */
546 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
547 const struct option *longopts, int *longind);
548 extern int getopt_long_only (int argc, char *const *argv,
549 const char *shortopts,
550 const struct option *longopts, int *longind);
552 /* Internal only. Users should not call this directly. */
553 extern int _getopt_internal (int argc, char *const *argv,
554 const char *shortopts,
555 const struct option *longopts, int *longind,
557 #else /* not __STDC__ */
558 extern int getopt ();
559 extern int getopt_long ();
560 extern int getopt_long_only ();
562 extern int _getopt_internal ();
563 #endif /* not __STDC__ */
569 #endif /* _GETOPT_H */
580 typedef struct dirent dir_type;
581 # define NLENGTH(dirent) ((int)strlen((dirent)->d_name))
582 # define DIR_OPT "DIRENT"
584 # define NLENGTH(dirent) ((dirent)->d_namlen)
586 # include <sys/dir.h>
587 typedef struct direct dir_type;
588 # define DIR_OPT "SYSDIR"
591 # include <sys/ndir.h>
592 typedef struct direct dir_type;
593 # define DIR_OPT "SYSNDIR"
597 typedef struct direct dir_type;
598 # define DIR_OPT "NDIR"
601 # define DIR_OPT "NO_DIR"
607 #if !defined(S_ISDIR) && defined(S_IFDIR)
608 # define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
610 #if !defined(S_ISREG) && defined(S_IFREG)
611 # define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
614 typedef RETSIGTYPE (*sig_type) OF((int));
617 # define O_BINARY 0 /* creation mode for open() */
621 /* Pure BSD system? */
622 # include <sys/file.h>
624 # define O_CREAT FCREAT
627 # define O_EXCL FEXCL
632 # define S_IRUSR 0400
635 # define S_IWUSR 0200
637 #define RW_USER (S_IRUSR | S_IWUSR) /* creation mode for open() */
640 # define MAX_PATH_LEN 1024 /* max pathname length */
649 off_t lseek OF((int fd, off_t offset, int whence));
655 DECLARE(uch, inbuf, INBUFSIZ +INBUF_EXTRA);
656 DECLARE(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
657 DECLARE(ush, d_buf, DIST_BUFSIZE);
658 DECLARE(uch, window, 2L*WSIZE);
660 DECLARE(ush, tab_prefix, 1L<<BITS);
662 DECLARE(ush, tab_prefix0, 1L<<(BITS-1));
663 DECLARE(ush, tab_prefix1, 1L<<(BITS-1));
666 /* local variables */
668 int force = 0; /* don't ask questions, compress links (-f) */
669 int foreground; /* set if program run in foreground */
670 int maxbits = BITS; /* max bits per code for LZW */
671 int method = DEFLATED;/* compression method */
672 int exit_code = OK; /* program exit code */
673 int last_member; /* set for .zip and .Z files */
674 int part_nb; /* number of parts in .gz file */
675 long ifile_size; /* input file size, -1 for devices (debug only) */
677 long bytes_in; /* number of input bytes */
678 long bytes_out; /* number of output bytes */
679 long total_in = 0; /* input bytes for all files */
680 long total_out = 0; /* output bytes for all files */
681 struct stat istat; /* status for input file */
682 int ifd; /* input file descriptor */
683 int ofd; /* output file descriptor */
684 unsigned insize; /* valid bytes in inbuf */
685 unsigned inptr; /* index of next byte to be processed in inbuf */
686 unsigned outcnt; /* bytes in output buffer */
688 long header_bytes; /* number of bytes in gzip header */
690 /* local functions */
692 local void treat_stdin OF((void));
693 local int get_method OF((int in));
694 local void do_exit OF((int exitcode));
695 int main OF((int argc, char **argv));
696 int (*work) OF((int infile, int outfile)) = unzip; /* function to call */
698 #define strequ(s1, s2) (strcmp((s1),(s2)) == 0)
700 /* ======================================================================== */
701 int zcat_main (int argc, char * * argv)
703 int file_count; /* number of files to precess */
705 foreground = signal(SIGINT, SIG_IGN) != SIG_IGN;
707 (void) signal (SIGINT, (sig_type)abort_gzip);
710 if (signal(SIGTERM, SIG_IGN) != SIG_IGN) {
711 (void) signal(SIGTERM, (sig_type)abort_gzip);
715 if (signal(SIGHUP, SIG_IGN) != SIG_IGN) {
716 (void) signal(SIGHUP, (sig_type)abort_gzip);
720 file_count = argc - optind;
722 /* Allocate all global buffers (for DYN_ALLOC option) */
723 ALLOC(uch, inbuf, INBUFSIZ +INBUF_EXTRA);
724 ALLOC(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
725 ALLOC(ush, d_buf, DIST_BUFSIZE);
726 ALLOC(uch, window, 2L*WSIZE);
728 ALLOC(ush, tab_prefix, 1L<<BITS);
730 ALLOC(ush, tab_prefix0, 1L<<(BITS-1));
731 ALLOC(ush, tab_prefix1, 1L<<(BITS-1));
734 /* And get to work */
738 return exit_code; /* just to avoid lint warning */
741 /* ========================================================================
742 * Compress or decompress stdin
744 local void treat_stdin()
746 ifile_size = -1L; /* convention for unknown size */
748 clear_bufs(); /* clear input and output buffers */
751 method = get_method(ifd);
754 do_exit(exit_code); /* error message already emitted */
757 (*work)(fileno(stdin), fileno(stdout));
762 /* ========================================================================
763 * Check the magic number of the input file and update ofname if an
764 * original name was given and to_stdout is not set.
765 * Return the compression method, -1 for error, -2 for warning.
766 * Set inptr to the offset of the next byte to be processed.
767 * Updates time_stamp if there is one and --no-time is not used.
768 * This function may be called repeatedly for an input file consisting
769 * of several contiguous gzip'ed members.
770 * IN assertions: there is at least one remaining compressed member.
771 * If the member is a zip file, it must be the only one.
773 local int get_method(in)
774 int in; /* input file descriptor */
776 uch flags; /* compression flags */
777 char magic[2]; /* magic header */
779 /* If --force and --stdout, zcat == cat, so do not complain about
780 * premature end of file: use try_byte instead of get_byte.
783 magic[0] = (char)try_byte();
784 magic[1] = (char)try_byte();
785 /* If try_byte returned EOF, magic[1] == 0xff */
787 magic[0] = (char)get_byte();
788 magic[1] = (char)get_byte();
790 method = -1; /* unknown yet */
791 part_nb++; /* number of parts in gzip file */
793 last_member = RECORD_IO;
794 /* assume multiple members in gzip file except for record oriented I/O */
796 if (memcmp(magic, GZIP_MAGIC, 2) == 0) {
798 method = (int)get_byte();
799 if (method != DEFLATED) {
801 "unknown method %d -- get newer version of gzip\n",
807 flags = (uch)get_byte();
809 (ulg)get_byte(); /* Ignore time stamp */
814 (void)get_byte(); /* Ignore extra flags for the moment */
815 (void)get_byte(); /* Ignore OS type for the moment */
817 if ((flags & EXTRA_FIELD) != 0) {
818 unsigned len = (unsigned)get_byte();
819 len |= ((unsigned)get_byte())<<8;
821 while (len--) (void)get_byte();
824 /* Discard original name if any */
825 if ((flags & ORIG_NAME) != 0) {
826 while (get_char() != 0) /* null */ ;
829 /* Discard file comment if any */
830 if ((flags & COMMENT) != 0) {
831 while (get_char() != 0) /* null */ ;
834 header_bytes = inptr + 2*sizeof(long); /* include crc and size */
839 if (method >= 0) return method;
842 fprintf(stderr, "\nnot in gzip format\n");
846 WARN((stderr, "\ndecompression OK, trailing garbage ignored\n"));
852 /* ========================================================================
853 * Free all dynamically allocated variables and exit with the given code.
855 local void do_exit(exitcode)
858 static int in_exit = 0;
860 if (in_exit) exit(exitcode);
875 /* ========================================================================
876 * Signal and error handler.
878 RETSIGTYPE abort_gzip()
882 /* unzip.c -- decompress files in gzip or pkzip format.
883 * Copyright (C) 1992-1993 Jean-loup Gailly
884 * This is free software; you can redistribute it and/or modify it under the
885 * terms of the GNU General Public License, see the file COPYING.
887 * The code in this file is derived from the file funzip.c written
888 * and put in the public domain by Mark Adler.
892 This version can extract files in gzip or pkzip format.
893 For the latter, only the first entry is extracted, and it has to be
894 either deflated or stored.
898 static char rcsid[] = "$Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $";
901 /* #include "crypt.h" */
903 /* crypt.h (dummy version) -- do not perform encryption
904 * Hardly worth copyrighting :-)
908 # undef CRYPT /* dummy version */
911 #define RAND_HEAD_LEN 12 /* length of encryption random header */
916 /* PKZIP header definitions */
917 #define LOCSIG 0x04034b50L /* four-byte lead-in (lsb first) */
918 #define LOCFLG 6 /* offset of bit flag */
919 #define CRPFLG 1 /* bit for encrypted entry */
920 #define EXTFLG 8 /* bit for extended local header */
921 #define LOCHOW 8 /* offset of compression method */
922 #define LOCTIM 10 /* file mod time (for decryption) */
923 #define LOCCRC 14 /* offset of crc */
924 #define LOCSIZ 18 /* offset of compressed size */
925 #define LOCLEN 22 /* offset of uncompressed length */
926 #define LOCFIL 26 /* offset of file name field length */
927 #define LOCEXT 28 /* offset of extra field length */
928 #define LOCHDR 30 /* size of local header, including sig */
929 #define EXTHDR 16 /* size of extended local header, inc sig */
934 char *key; /* not used--needed to link crypt.c */
935 int pkzip = 0; /* set for a pkzip file */
936 int ext_header = 0; /* set if extended local header */
938 /* ===========================================================================
939 * Unzip in to out. This routine works on both gzip and pkzip files.
941 * IN assertions: the buffer inbuf contains already the beginning of
942 * the compressed data, from offsets inptr to insize-1 included.
943 * The magic header has already been checked. The output buffer is cleared.
946 int in, out; /* input and output file descriptors */
948 ulg orig_crc = 0; /* original crc */
949 ulg orig_len = 0; /* original uncompressed length */
951 uch buf[EXTHDR]; /* extended local header */
956 updcrc(NULL, 0); /* initialize crc */
958 if (pkzip && !ext_header) { /* crc and length at the end otherwise */
959 orig_crc = LG(inbuf + LOCCRC);
960 orig_len = LG(inbuf + LOCLEN);
964 if (method == DEFLATED) {
969 error("out of memory");
970 } else if (res != 0) {
971 error("invalid compressed data--format violated");
975 error("internal error, invalid method");
978 /* Get the crc and original length */
980 /* crc32 (see algorithm.doc)
981 * uncompressed input size modulo 2^32
983 for (n = 0; n < 8; n++) {
984 buf[n] = (uch)get_byte(); /* may cause an error if EOF */
987 orig_len = LG(buf+4);
989 } else if (ext_header) { /* If extended header, check it */
990 /* signature - 4bytes: 0x50 0x4b 0x07 0x08
992 * compressed size 4-bytes
993 * uncompressed size 4-bytes
995 for (n = 0; n < EXTHDR; n++) {
996 buf[n] = (uch)get_byte(); /* may cause an error if EOF */
998 orig_crc = LG(buf+4);
999 orig_len = LG(buf+12);
1002 /* Validate decompression */
1003 if (orig_crc != updcrc(outbuf, 0)) {
1004 error("invalid compressed data--crc error");
1006 if (orig_len != (ulg)bytes_out) {
1007 error("invalid compressed data--length error");
1010 /* Check if there are more entries in a pkzip file */
1011 if (pkzip && inptr + 4 < insize && LG(inbuf+inptr) == LOCSIG) {
1012 WARN((stderr,"has more than one entry--rest ignored\n"));
1014 ext_header = pkzip = 0; /* for next file */
1017 /* util.c -- utility functions for gzip support
1018 * Copyright (C) 1992-1993 Jean-loup Gailly
1019 * This is free software; you can redistribute it and/or modify it under the
1020 * terms of the GNU General Public License, see the file COPYING.
1024 static char rcsid[] = "$Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $";
1029 #include <sys/types.h>
1031 #ifdef HAVE_UNISTD_H
1032 # include <unistd.h>
1038 #if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
1039 # include <stdlib.h>
1044 const ulg crc_32_tab[]; /* crc table, defined below */
1046 /* ===========================================================================
1047 * Run a set of bytes through the crc shift register. If s is a NULL
1048 * pointer, then initialize the crc shift register contents instead.
1049 * Return the current crc in either case.
1052 uch *s; /* pointer to bytes to pump through */
1053 unsigned n; /* number of bytes in s[] */
1055 register ulg c; /* temporary variable */
1057 static ulg crc = (ulg)0xffffffffL; /* shift register contents */
1064 c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
1068 return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */
1071 /* ===========================================================================
1072 * Clear input and output buffers
1078 bytes_in = bytes_out = 0L;
1081 /* ===========================================================================
1082 * Fill the input buffer. This is called only when the buffer is empty.
1084 int fill_inbuf(eof_ok)
1085 int eof_ok; /* set if EOF acceptable as a result */
1089 /* Read as much as possible */
1093 len = read(ifd, (char*)inbuf+insize, INBUFSIZ-insize);
1094 if (len == 0 || len == EOF) break;
1096 } while (insize < INBUFSIZ);
1099 if (eof_ok) return EOF;
1102 bytes_in += (ulg)insize;
1107 /* ===========================================================================
1108 * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
1109 * (used for the compressed data only)
1113 if (outcnt == 0) return;
1115 write_buf(ofd, (char *)outbuf, outcnt);
1116 bytes_out += (ulg)outcnt;
1120 /* ===========================================================================
1121 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
1122 * (Used for the decompressed data only.)
1126 if (outcnt == 0) return;
1127 updcrc(window, outcnt);
1129 write_buf(ofd, (char *)window, outcnt);
1131 bytes_out += (ulg)outcnt;
1135 /* ===========================================================================
1136 * Does the same as write(), but also handles partial pipe writes and checks
1139 void write_buf(fd, buf, cnt)
1146 while ((n = write(fd, buf, cnt)) != cnt) {
1147 if (n == (unsigned)(-1)) {
1151 buf = (voidp)((char*)buf+n);
1155 #if defined(NO_STRING_H) && !defined(STDC_HEADERS)
1157 /* Provide missing strspn and strcspn functions. */
1163 int strspn OF((const char *s, const char *accept));
1164 int strcspn OF((const char *s, const char *reject));
1166 /* ========================================================================
1167 * Return the length of the maximum initial segment
1168 * of s which contains only characters in accept.
1170 int strspn(s, accept)
1174 register const char *p;
1175 register const char *a;
1176 register int count = 0;
1178 for (p = s; *p != '\0'; ++p) {
1179 for (a = accept; *a != '\0'; ++a) {
1180 if (*p == *a) break;
1182 if (*a == '\0') return count;
1188 /* ========================================================================
1189 * Return the length of the maximum inital segment of s
1190 * which contains no characters from reject.
1192 int strcspn(s, reject)
1196 register int count = 0;
1198 while (*s != '\0') {
1199 if (strchr(reject, *s++) != NULL) return count;
1205 #endif /* NO_STRING_H */
1208 /* ========================================================================
1214 fprintf(stderr, "\n%s\n", m);
1219 char *a, *b; /* message strings juxtaposed in output */
1221 WARN((stderr, "warning: %s%s\n", a, b));
1226 fprintf(stderr, "\n");
1230 fprintf(stderr, "unexpected end of file\n");
1237 fprintf(stderr, "\n");
1243 /* ========================================================================
1244 * Semi-safe malloc -- never returns NULL.
1246 voidp xmalloc (size)
1249 voidp cp = (voidp)malloc (size);
1251 if (cp == NULL) error("out of memory");
1255 /* ========================================================================
1256 * Table of CRC-32's of all single-byte values (made by makecrc.c)
1258 const ulg crc_32_tab[] = {
1259 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
1260 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
1261 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
1262 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
1263 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
1264 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
1265 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
1266 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
1267 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
1268 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
1269 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
1270 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
1271 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
1272 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
1273 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
1274 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
1275 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
1276 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
1277 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
1278 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
1279 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
1280 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
1281 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
1282 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
1283 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
1284 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
1285 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
1286 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
1287 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
1288 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
1289 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
1290 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
1291 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
1292 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
1293 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
1294 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
1295 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
1296 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
1297 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
1298 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
1299 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
1300 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
1301 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
1302 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
1303 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
1304 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
1305 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
1306 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
1307 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
1308 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
1309 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
1312 /* inflate.c -- Not copyrighted 1992 by Mark Adler
1313 version c10p1, 10 January 1993 */
1315 /* You can do whatever you like with this source file, though I would
1316 prefer that if you modify it and redistribute it that you include
1317 comments to that effect with your name and the date. Thank you.
1318 [The history has been moved to the file ChangeLog.]
1322 Inflate deflated (PKZIP's method 8 compressed) data. The compression
1323 method searches for as much of the current string of bytes (up to a
1324 length of 258) in the previous 32K bytes. If it doesn't find any
1325 matches (of at least length 3), it codes the next byte. Otherwise, it
1326 codes the length of the matched string and its distance backwards from
1327 the current position. There is a single Huffman code that codes both
1328 single bytes (called "literals") and match lengths. A second Huffman
1329 code codes the distance information, which follows a length code. Each
1330 length or distance code actually represents a base value and a number
1331 of "extra" (sometimes zero) bits to get to add to the base value. At
1332 the end of each deflated block is a special end-of-block (EOB) literal/
1333 length code. The decoding process is basically: get a literal/length
1334 code; if EOB then done; if a literal, emit the decoded byte; if a
1335 length then get the distance and emit the referred-to bytes from the
1336 sliding window of previously emitted data.
1338 There are (currently) three kinds of inflate blocks: stored, fixed, and
1339 dynamic. The compressor deals with some chunk of data at a time, and
1340 decides which method to use on a chunk-by-chunk basis. A chunk might
1341 typically be 32K or 64K. If the chunk is uncompressible, then the
1342 "stored" method is used. In this case, the bytes are simply stored as
1343 is, eight bits per byte, with none of the above coding. The bytes are
1344 preceded by a count, since there is no longer an EOB code.
1346 If the data is compressible, then either the fixed or dynamic methods
1347 are used. In the dynamic method, the compressed data is preceded by
1348 an encoding of the literal/length and distance Huffman codes that are
1349 to be used to decode this block. The representation is itself Huffman
1350 coded, and so is preceded by a description of that code. These code
1351 descriptions take up a little space, and so for small blocks, there is
1352 a predefined set of codes, called the fixed codes. The fixed method is
1353 used if the block codes up smaller that way (usually for quite small
1354 chunks), otherwise the dynamic method is used. In the latter case, the
1355 codes are customized to the probabilities in the current block, and so
1356 can code it much better than the pre-determined fixed codes.
1358 The Huffman codes themselves are decoded using a mutli-level table
1359 lookup, in order to maximize the speed of decoding plus the speed of
1360 building the decoding tables. See the comments below that precede the
1361 lbits and dbits tuning parameters.
1366 Notes beyond the 1.93a appnote.txt:
1368 1. Distance pointers never point before the beginning of the output
1370 2. Distance pointers can point back across blocks, up to 32k away.
1371 3. There is an implied maximum of 7 bits for the bit length table and
1372 15 bits for the actual data.
1373 4. If only one code exists, then it is encoded using one bit. (Zero
1374 would be more efficient, but perhaps a little confusing.) If two
1375 codes exist, they are coded using one bit each (0 and 1).
1376 5. There is no way of sending zero distance codes--a dummy must be
1377 sent if there are none. (History: a pre 2.0 version of PKZIP would
1378 store blocks with no distance codes, but this was discovered to be
1379 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
1380 zero distance codes, which is sent as one code of zero bits in
1382 6. There are up to 286 literal/length codes. Code 256 represents the
1383 end-of-block. Note however that the static length tree defines
1384 288 codes just to fill out the Huffman codes. Codes 286 and 287
1385 cannot be used though, since there is no length base or extra bits
1386 defined for them. Similarly, there are up to 30 distance codes.
1387 However, static trees define 32 codes (all 5 bits) to fill out the
1388 Huffman codes, but the last two had better not show up in the data.
1389 7. Unzip can check dynamic Huffman blocks for complete code sets.
1390 The exception is that a single code would not be complete (see #4).
1391 8. The five bits following the block type is really the number of
1392 literal codes sent minus 257.
1393 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
1394 (1+6+6). Therefore, to output three times the length, you output
1395 three codes (1+1+1), whereas to output four times the same length,
1396 you only need two codes (1+3). Hmm.
1397 10. In the tree reconstruction algorithm, Code = Code + Increment
1398 only if BitLength(i) is not zero. (Pretty obvious.)
1399 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
1400 12. Note: length code 284 can represent 227-258, but length code 285
1401 really is 258. The last length deserves its own, short code
1402 since it gets used a lot in very redundant files. The length
1403 258 is special since 258 - 3 (the min match length) is 255.
1404 13. The literal/length and distance code bit lengths are read as a
1405 single stream of lengths. It is possible (and advantageous) for
1406 a repeat code (16, 17, or 18) to go across the boundary between
1407 the two sets of lengths.
1411 static char rcsid[] = "$Id: zcat.c,v 1.4 1999/10/19 22:26:25 andersen Exp $";
1414 #include <sys/types.h>
1416 #if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
1417 # include <stdlib.h>
1421 #define slide window
1423 /* Huffman code lookup table entry--this entry is four bytes for machines
1424 that have 16-bit pointers (e.g. PC's in the small or medium model).
1425 Valid extra bits are 0..13. e == 15 is EOB (end of block), e == 16
1426 means that v is a literal, 16 < e < 32 means that v is a pointer to
1427 the next table, which codes e - 16 bits, and lastly e == 99 indicates
1428 an unused code. If a code with e == 99 is looked up, this implies an
1429 error in the data. */
1431 uch e; /* number of extra bits or operation */
1432 uch b; /* number of bits in this code or subcode */
1434 ush n; /* literal, length base, or distance base */
1435 struct huft *t; /* pointer to next level of table */
1440 /* Function prototypes */
1441 int huft_build OF((unsigned *, unsigned, unsigned, ush *, ush *,
1442 struct huft **, int *));
1443 int huft_free OF((struct huft *));
1444 int inflate_codes OF((struct huft *, struct huft *, int, int));
1445 int inflate_stored OF((void));
1446 int inflate_fixed OF((void));
1447 int inflate_dynamic OF((void));
1448 int inflate_block OF((int *));
1449 int inflate OF((void));
1452 /* The inflate algorithm uses a sliding 32K byte window on the uncompressed
1453 stream to find repeated byte strings. This is implemented here as a
1454 circular buffer. The index is updated simply by incrementing and then
1455 and'ing with 0x7fff (32K-1). */
1456 /* It is left to other modules to supply the 32K area. It is assumed
1457 to be usable as if it were declared "uch slide[32768];" or as just
1458 "uch *slide;" and then malloc'ed in the latter case. The definition
1459 must be in unzip.h, included above. */
1460 /* unsigned wp; current position in slide */
1462 #define flush_output(w) (wp=(w),flush_window())
1464 /* Tables for deflate from PKZIP's appnote.txt. */
1465 static unsigned border[] = { /* Order of the bit length code lengths */
1466 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
1467 static ush cplens[] = { /* Copy lengths for literal codes 257..285 */
1468 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
1469 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
1470 /* note: see note #13 above about the 258 in this list. */
1471 static ush cplext[] = { /* Extra bits for literal codes 257..285 */
1472 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
1473 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
1474 static ush cpdist[] = { /* Copy offsets for distance codes 0..29 */
1475 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
1476 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
1477 8193, 12289, 16385, 24577};
1478 static ush cpdext[] = { /* Extra bits for distance codes */
1479 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
1480 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
1485 /* Macros for inflate() bit peeking and grabbing.
1489 x = b & mask_bits[j];
1492 where NEEDBITS makes sure that b has at least j bits in it, and
1493 DUMPBITS removes the bits from b. The macros use the variable k
1494 for the number of bits in b. Normally, b and k are register
1495 variables for speed, and are initialized at the beginning of a
1496 routine that uses these macros from a global bit buffer and count.
1498 If we assume that EOB will be the longest code, then we will never
1499 ask for bits with NEEDBITS that are beyond the end of the stream.
1500 So, NEEDBITS should not read any more bytes than are needed to
1501 meet the request. Then no bytes need to be "returned" to the buffer
1502 at the end of the last block.
1504 However, this assumption is not true for fixed blocks--the EOB code
1505 is 7 bits, but the other literal/length codes can be 8 or 9 bits.
1506 (The EOB code is shorter than other codes because fixed blocks are
1507 generally short. So, while a block always has an EOB, many other
1508 literal/length codes have a significantly lower probability of
1509 showing up at all.) However, by making the first table have a
1510 lookup of seven bits, the EOB code will be found in that first
1511 lookup, and so will not require that too many bits be pulled from
1515 ulg bb; /* bit buffer */
1516 unsigned bk; /* bits in bit buffer */
1520 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
1521 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
1526 # define NEXTBYTE() (cc = get_byte(), zdecode(cc), cc)
1528 # define NEXTBYTE() (uch)get_byte()
1530 #define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
1531 #define DUMPBITS(n) {b>>=(n);k-=(n);}
1535 Huffman code decoding is performed using a multi-level table lookup.
1536 The fastest way to decode is to simply build a lookup table whose
1537 size is determined by the longest code. However, the time it takes
1538 to build this table can also be a factor if the data being decoded
1539 is not very long. The most common codes are necessarily the
1540 shortest codes, so those codes dominate the decoding time, and hence
1541 the speed. The idea is you can have a shorter table that decodes the
1542 shorter, more probable codes, and then point to subsidiary tables for
1543 the longer codes. The time it costs to decode the longer codes is
1544 then traded against the time it takes to make longer tables.
1546 This results of this trade are in the variables lbits and dbits
1547 below. lbits is the number of bits the first level table for literal/
1548 length codes can decode in one step, and dbits is the same thing for
1549 the distance codes. Subsequent tables are also less than or equal to
1550 those sizes. These values may be adjusted either when all of the
1551 codes are shorter than that, in which case the longest code length in
1552 bits is used, or when the shortest code is *longer* than the requested
1553 table size, in which case the length of the shortest code in bits is
1556 There are two different values for the two tables, since they code a
1557 different number of possibilities each. The literal/length table
1558 codes 286 possible values, or in a flat code, a little over eight
1559 bits. The distance table codes 30 possible values, or a little less
1560 than five bits, flat. The optimum values for speed end up being
1561 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
1562 The optimum values may differ though from machine to machine, and
1563 possibly even between compilers. Your mileage may vary.
1567 int lbits = 9; /* bits in base literal/length lookup table */
1568 int dbits = 6; /* bits in base distance lookup table */
1571 /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
1572 #define BMAX 16 /* maximum bit length of any code (16 for explode) */
1573 #define N_MAX 288 /* maximum number of codes in any set */
1576 unsigned hufts; /* track memory usage */
1579 int huft_build(b, n, s, d, e, t, m)
1580 unsigned *b; /* code lengths in bits (all assumed <= BMAX) */
1581 unsigned n; /* number of codes (assumed <= N_MAX) */
1582 unsigned s; /* number of simple-valued codes (0..s-1) */
1583 ush *d; /* list of base values for non-simple codes */
1584 ush *e; /* list of extra bits for non-simple codes */
1585 struct huft **t; /* result: starting table */
1586 int *m; /* maximum lookup bits, returns actual */
1587 /* Given a list of code lengths and a maximum table size, make a set of
1588 tables to decode that set of codes. Return zero on success, one if
1589 the given code set is incomplete (the tables are still built in this
1590 case), two if the input is invalid (all zero length codes or an
1591 oversubscribed set of lengths), and three if not enough memory. */
1593 unsigned a; /* counter for codes of length k */
1594 unsigned c[BMAX+1]; /* bit length count table */
1595 unsigned f; /* i repeats in table every f entries */
1596 int g; /* maximum code length */
1597 int h; /* table level */
1598 register unsigned i; /* counter, current code */
1599 register unsigned j; /* counter */
1600 register int k; /* number of bits in current code */
1601 int l; /* bits per table (returned in m) */
1602 register unsigned *p; /* pointer into c[], b[], or v[] */
1603 register struct huft *q; /* points to current table */
1604 struct huft r; /* table entry for structure assignment */
1605 struct huft *u[BMAX]; /* table stack */
1606 unsigned v[N_MAX]; /* values in order of bit length */
1607 register int w; /* bits before this table == (l * h) */
1608 unsigned x[BMAX+1]; /* bit offsets, then code stack */
1609 unsigned *xp; /* pointer into x */
1610 int y; /* number of dummy codes added */
1611 unsigned z; /* number of entries in current table */
1614 /* Generate counts for each bit length */
1615 memzero(c, sizeof(c));
1618 Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"),
1620 c[*p]++; /* assume all entries <= BMAX */
1621 p++; /* Can't combine with above line (Solaris bug) */
1623 if (c[0] == n) /* null input--all zero length codes */
1625 *t = (struct huft *)NULL;
1631 /* Find minimum and maximum length, bound *m by those */
1633 for (j = 1; j <= BMAX; j++)
1636 k = j; /* minimum code length */
1637 if ((unsigned)l < j)
1639 for (i = BMAX; i; i--)
1642 g = i; /* maximum code length */
1643 if ((unsigned)l > i)
1648 /* Adjust last length count to fill out codes, if needed */
1649 for (y = 1 << j; j < i; j++, y <<= 1)
1650 if ((y -= c[j]) < 0)
1651 return 2; /* bad input: more codes than bits */
1652 if ((y -= c[i]) < 0)
1657 /* Generate starting offsets into the value table for each length */
1659 p = c + 1; xp = x + 2;
1660 while (--i) { /* note that i == g from above */
1661 *xp++ = (j += *p++);
1665 /* Make a table of values in order of bit lengths */
1668 if ((j = *p++) != 0)
1673 /* Generate the Huffman codes and for each, make the table entries */
1674 x[0] = i = 0; /* first Huffman code is zero */
1675 p = v; /* grab values in bit order */
1676 h = -1; /* no tables yet--level -1 */
1677 w = -l; /* bits decoded == (l * h) */
1678 u[0] = (struct huft *)NULL; /* just to keep compilers happy */
1679 q = (struct huft *)NULL; /* ditto */
1682 /* go through the bit lengths (k already is bits in shortest code) */
1688 /* here i is the Huffman code of length k bits for value *p */
1689 /* make tables up to required level */
1693 w += l; /* previous table always l bits */
1695 /* compute minimum size table less than or equal to l bits */
1696 z = (z = g - w) > (unsigned)l ? l : z; /* upper limit on table size */
1697 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
1698 { /* too few codes for k-w bit table */
1699 f -= a + 1; /* deduct codes from patterns left */
1701 while (++j < z) /* try smaller tables up to z bits */
1703 if ((f <<= 1) <= *++xp)
1704 break; /* enough codes to use up j bits */
1705 f -= *xp; /* else deduct codes from patterns */
1708 z = 1 << j; /* table entries for j-bit table */
1710 /* allocate and link in new table */
1711 if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
1712 (struct huft *)NULL)
1716 return 3; /* not enough memory */
1718 hufts += z + 1; /* track memory usage */
1719 *t = q + 1; /* link to list for huft_free() */
1720 *(t = &(q->v.t)) = (struct huft *)NULL;
1721 u[h] = ++q; /* table starts after link */
1723 /* connect to last table, if there is one */
1726 x[h] = i; /* save pattern for backing up */
1727 r.b = (uch)l; /* bits to dump before this table */
1728 r.e = (uch)(16 + j); /* bits in this table */
1729 r.v.t = q; /* pointer to this table */
1730 j = i >> (w - l); /* (get around Turbo C bug) */
1731 u[h-1][j] = r; /* connect to last table */
1735 /* set up table entry in r */
1738 r.e = 99; /* out of values--invalid code */
1741 r.e = (uch)(*p < 256 ? 16 : 15); /* 256 is end-of-block code */
1742 r.v.n = (ush)(*p); /* simple code is just the value */
1743 p++; /* one compiler does not like *p++ */
1747 r.e = (uch)e[*p - s]; /* non-simple--look up in lists */
1748 r.v.n = d[*p++ - s];
1751 /* fill code-like entries with r */
1753 for (j = i >> w; j < z; j += f)
1756 /* backwards increment the k-bit code i */
1757 for (j = 1 << (k - 1); i & j; j >>= 1)
1761 /* backup over finished tables */
1762 while ((i & ((1 << w) - 1)) != x[h])
1764 h--; /* don't need to update q */
1771 /* Return true (1) if we were given an incomplete table */
1772 return y != 0 && g != 1;
1778 struct huft *t; /* table to free */
1779 /* Free the malloc'ed tables built by huft_build(), which makes a linked
1780 list of the tables it made, with the links in a dummy first entry of
1783 register struct huft *p, *q;
1786 /* Go through linked list, freeing from the malloced (t[-1]) address. */
1788 while (p != (struct huft *)NULL)
1798 int inflate_codes(tl, td, bl, bd)
1799 struct huft *tl, *td; /* literal/length and distance decoder tables */
1800 int bl, bd; /* number of bits decoded by tl[] and td[] */
1801 /* inflate (decompress) the codes in a deflated (compressed) block.
1802 Return an error code or zero if it all goes ok. */
1804 register unsigned e; /* table entry flag/number of extra bits */
1805 unsigned n, d; /* length and index for copy */
1806 unsigned w; /* current window position */
1807 struct huft *t; /* pointer to table entry */
1808 unsigned ml, md; /* masks for bl and bd bits */
1809 register ulg b; /* bit buffer */
1810 register unsigned k; /* number of bits in bit buffer */
1813 /* make local copies of globals */
1814 b = bb; /* initialize bit buffer */
1816 w = wp; /* initialize window position */
1818 /* inflate the coded data */
1819 ml = mask_bits[bl]; /* precompute masks for speed */
1821 for (;;) /* do until end of block */
1823 NEEDBITS((unsigned)bl)
1824 if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
1831 } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
1833 if (e == 16) /* then it's a literal */
1835 slide[w++] = (uch)t->v.n;
1836 Tracevv((stderr, "%c", slide[w-1]));
1843 else /* it's an EOB or a length */
1845 /* exit if end of block */
1849 /* get length of block to copy */
1851 n = t->v.n + ((unsigned)b & mask_bits[e]);
1854 /* decode distance of block to copy */
1855 NEEDBITS((unsigned)bd)
1856 if ((e = (t = td + ((unsigned)b & md))->e) > 16)
1863 } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
1866 d = w - t->v.n - ((unsigned)b & mask_bits[e]);
1868 Tracevv((stderr,"\\[%d,%d]", w-d, n));
1872 n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
1873 #if !defined(NOMEMCPY) && !defined(DEBUG)
1874 if (w - d >= e) /* (this test assumes unsigned comparison) */
1876 memcpy(slide + w, slide + d, e);
1880 else /* do it slow to avoid memcpy() overlap */
1881 #endif /* !NOMEMCPY */
1883 slide[w++] = slide[d++];
1884 Tracevv((stderr, "%c", slide[w-1]));
1896 /* restore the globals from the locals */
1897 wp = w; /* restore global window pointer */
1898 bb = b; /* restore global bit buffer */
1907 int inflate_stored()
1908 /* "decompress" an inflated type 0 (stored) block. */
1910 unsigned n; /* number of bytes in block */
1911 unsigned w; /* current window position */
1912 register ulg b; /* bit buffer */
1913 register unsigned k; /* number of bits in bit buffer */
1916 /* make local copies of globals */
1917 b = bb; /* initialize bit buffer */
1919 w = wp; /* initialize window position */
1922 /* go to byte boundary */
1927 /* get the length and its complement */
1929 n = ((unsigned)b & 0xffff);
1932 if (n != (unsigned)((~b) & 0xffff))
1933 return 1; /* error in compressed data */
1937 /* read and output the compressed data */
1941 slide[w++] = (uch)b;
1951 /* restore the globals from the locals */
1952 wp = w; /* restore global window pointer */
1953 bb = b; /* restore global bit buffer */
1961 /* decompress an inflated type 1 (fixed Huffman codes) block. We should
1962 either replace this with a custom decoder, or at least precompute the
1965 int i; /* temporary variable */
1966 struct huft *tl; /* literal/length code table */
1967 struct huft *td; /* distance code table */
1968 int bl; /* lookup bits for tl */
1969 int bd; /* lookup bits for td */
1970 unsigned l[288]; /* length list for huft_build */
1973 /* set up literal table */
1974 for (i = 0; i < 144; i++)
1976 for (; i < 256; i++)
1978 for (; i < 280; i++)
1980 for (; i < 288; i++) /* make a complete, but wrong code set */
1983 if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
1987 /* set up distance table */
1988 for (i = 0; i < 30; i++) /* make an incomplete code set */
1991 if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
1998 /* decompress until an end-of-block code */
1999 if (inflate_codes(tl, td, bl, bd))
2003 /* free the decoding tables, return */
2011 int inflate_dynamic()
2012 /* decompress an inflated type 2 (dynamic Huffman codes) block. */
2014 int i; /* temporary variables */
2016 unsigned l; /* last length */
2017 unsigned m; /* mask for bit lengths table */
2018 unsigned n; /* number of lengths to get */
2019 struct huft *tl; /* literal/length code table */
2020 struct huft *td; /* distance code table */
2021 int bl; /* lookup bits for tl */
2022 int bd; /* lookup bits for td */
2023 unsigned nb; /* number of bit length codes */
2024 unsigned nl; /* number of literal/length codes */
2025 unsigned nd; /* number of distance codes */
2026 #ifdef PKZIP_BUG_WORKAROUND
2027 unsigned ll[288+32]; /* literal/length and distance code lengths */
2029 unsigned ll[286+30]; /* literal/length and distance code lengths */
2031 register ulg b; /* bit buffer */
2032 register unsigned k; /* number of bits in bit buffer */
2035 /* make local bit buffer */
2040 /* read in table lengths */
2042 nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */
2045 nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */
2048 nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */
2050 #ifdef PKZIP_BUG_WORKAROUND
2051 if (nl > 288 || nd > 32)
2053 if (nl > 286 || nd > 30)
2055 return 1; /* bad lengths */
2058 /* read in bit-length-code lengths */
2059 for (j = 0; j < nb; j++)
2062 ll[border[j]] = (unsigned)b & 7;
2069 /* build decoding table for trees--single level, 7 bit lookup */
2071 if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
2075 return i; /* incomplete code set */
2079 /* read in literal and distance code lengths */
2083 while ((unsigned)i < n)
2085 NEEDBITS((unsigned)bl)
2086 j = (td = tl + ((unsigned)b & m))->b;
2089 if (j < 16) /* length of code in bits (0..15) */
2090 ll[i++] = l = j; /* save last length in l */
2091 else if (j == 16) /* repeat last length 3 to 6 times */
2094 j = 3 + ((unsigned)b & 3);
2096 if ((unsigned)i + j > n)
2101 else if (j == 17) /* 3 to 10 zero length codes */
2104 j = 3 + ((unsigned)b & 7);
2106 if ((unsigned)i + j > n)
2112 else /* j == 18: 11 to 138 zero length codes */
2115 j = 11 + ((unsigned)b & 0x7f);
2117 if ((unsigned)i + j > n)
2126 /* free decoding table for trees */
2130 /* restore the global bit buffer */
2135 /* build the decoding tables for literal/length and distance codes */
2137 if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
2140 fprintf(stderr, " incomplete literal tree\n");
2143 return i; /* incomplete code set */
2146 if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
2149 fprintf(stderr, " incomplete distance tree\n");
2150 #ifdef PKZIP_BUG_WORKAROUND
2157 return i; /* incomplete code set */
2162 /* decompress until an end-of-block code */
2163 if (inflate_codes(tl, td, bl, bd))
2167 /* free the decoding tables, return */
2175 int inflate_block(e)
2176 int *e; /* last block flag */
2177 /* decompress an inflated block */
2179 unsigned t; /* block type */
2180 register ulg b; /* bit buffer */
2181 register unsigned k; /* number of bits in bit buffer */
2184 /* make local bit buffer */
2189 /* read in last block bit */
2195 /* read in block type */
2197 t = (unsigned)b & 3;
2201 /* restore the global bit buffer */
2206 /* inflate that block type */
2208 return inflate_dynamic();
2210 return inflate_stored();
2212 return inflate_fixed();
2215 /* bad block type */
2222 /* decompress an inflated entry */
2224 int e; /* last block flag */
2225 int r; /* result code */
2226 unsigned h; /* maximum struct huft's malloc'ed */
2229 /* initialize window, bit buffer */
2235 /* decompress until the last block */
2239 if ((r = inflate_block(&e)) != 0)
2245 /* Undo too much lookahead. The next read will be byte aligned so we
2246 * can discard unused bits in the last meaningful byte.
2253 /* flush out slide */
2257 /* return success */
2259 fprintf(stderr, "<%u> ", h);