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Diffstat (limited to 'zcat.c')
| -rw-r--r-- | zcat.c | 2262 |
1 files changed, 2262 insertions, 0 deletions
@@ -0,0 +1,2262 @@ +/* zcat : stripped version based on gzip sources + Sven Rudolph <sr1@inf.tu-dresden.de> + */ + +#include "internal.h" + +const char zcat_usage[] = "zcat\n" +"\n" +"\tuncompress gzipped data from stdin to stdout\n"; + + + +/* 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. + */ + +#ifdef RCSID +static char rcsid[] = "$Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $"; +#endif + +#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. + */ + +/* $Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $ */ + +#define RECORD_IO 0 + +#define get_char() get_byte() +#define put_char(c) put_byte(c) + +/* #include "gzip.h" */ + +/* gzip.h -- common declarations for all gzip modules + * 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(__STDC__) || defined(PROTO) +# define OF(args) args +#else +# define OF(args) () +#endif + +#ifdef __STDC__ + typedef void *voidp; +#else + typedef char *voidp; +#endif + +/* 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 ((voidp)(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) error("insufficient memory"); \ + } +# 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 int ifd; /* input file descriptor */ +extern int ofd; /* output file descriptor */ + +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 to_stdout; /* output to stdout (-c) */ +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)) error(msg);} +# define Trace(x) fprintf x +# define Tracev(x) {if (verbose) fprintf x ;} +# define Tracevv(x) {if (verbose>1) fprintf x ;} +# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} +# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} +#else +# define Assert(cond,msg) +# define Trace(x) +# define Tracev(x) +# define Tracevv(x) +# define Tracec(c,x) +# define Tracecv(c,x) +#endif + +#define WARN(msg) {fprintf msg ; \ + if (exit_code == OK) exit_code = WARNING;} + + /* in unzip.c */ +extern int unzip OF((int in, int out)); + + /* in gzip.c */ +RETSIGTYPE abort_gzip OF((void)); + + /* in deflate.c */ +void lm_init OF((int pack_level, ush *flags)); +ulg deflate OF((void)); + + /* in trees.c */ +void ct_init OF((ush *attr, int *method)); +int ct_tally OF((int dist, int lc)); +ulg flush_block OF((char *buf, ulg stored_len, int eof)); + + /* in bits.c */ +void bi_init OF((file_t zipfile)); +void send_bits OF((int value, int length)); +unsigned bi_reverse OF((unsigned value, int length)); +void bi_windup OF((void)); +void copy_block OF((char *buf, unsigned len, int header)); +extern int (*read_buf) OF((char *buf, unsigned size)); + + /* in util.c: */ +extern int copy OF((int in, int out)); +extern ulg updcrc OF((uch *s, unsigned n)); +extern void clear_bufs OF((void)); +extern int fill_inbuf OF((int eof_ok)); +extern void flush_outbuf OF((void)); +extern void flush_window OF((void)); +extern void write_buf OF((int fd, voidp buf, unsigned cnt)); +#ifndef __linux__ +extern char *basename OF((char *fname)); +#endif /* not __linux__ */ +extern void error OF((char *m)); +extern void warn OF((char *a, char *b)); +extern void read_error OF((void)); +extern void write_error OF((void)); +extern voidp xmalloc OF((unsigned int size)); + + /* in inflate.c */ +extern int inflate OF((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 OF((int in, int out)); +extern int unlzw OF((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 + +/* $Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $ */ + +/* #include "getopt.h" */ + +/* Declarations for getopt. + Copyright (C) 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc. + + 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, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#ifndef _GETOPT_H +#define _GETOPT_H 1 + +#ifdef __cplusplus +extern "C" { +#endif + +/* For communication from `getopt' to the caller. + When `getopt' finds an option that takes an argument, + the argument value is returned here. + Also, when `ordering' is RETURN_IN_ORDER, + each non-option ARGV-element is returned here. */ + +extern char *optarg; + +/* Index in ARGV of the next element to be scanned. + This is used for communication to and from the caller + and for communication between successive calls to `getopt'. + + On entry to `getopt', zero means this is the first call; initialize. + + When `getopt' returns EOF, this is the index of the first of the + non-option elements that the caller should itself scan. + + Otherwise, `optind' communicates from one call to the next + how much of ARGV has been scanned so far. */ + +extern int optind; + +/* Callers store zero here to inhibit the error message `getopt' prints + for unrecognized options. */ + +extern int opterr; + +/* Set to an option character which was unrecognized. */ + +extern int optopt; + +/* Describe the long-named options requested by the application. + The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector + of `struct option' terminated by an element containing a name which is + zero. + + The field `has_arg' is: + no_argument (or 0) if the option does not take an argument, + required_argument (or 1) if the option requires an argument, + optional_argument (or 2) if the option takes an optional argument. + + If the field `flag' is not NULL, it points to a variable that is set + to the value given in the field `val' when the option is found, but + left unchanged if the option is not found. + + To have a long-named option do something other than set an `int' to + a compiled-in constant, such as set a value from `optarg', set the + option's `flag' field to zero and its `val' field to a nonzero + value (the equivalent single-letter option character, if there is + one). For long options that have a zero `flag' field, `getopt' + returns the contents of the `val' field. */ + +struct option +{ +#if __STDC__ + const char *name; +#else + char *name; +#endif + /* has_arg can't be an enum because some compilers complain about + type mismatches in all the code that assumes it is an int. */ + int has_arg; + int *flag; + int val; +}; + +/* Names for the values of the `has_arg' field of `struct option'. */ + +#define no_argument 0 +#define required_argument 1 +#define optional_argument 2 + +#if __STDC__ || defined(PROTO) +#if defined(__GNU_LIBRARY__) +/* Many other libraries have conflicting prototypes for getopt, with + differences in the consts, in stdlib.h. To avoid compilation + errors, only prototype getopt for the GNU C library. */ +extern int getopt (int argc, char *const *argv, const char *shortopts); +#endif /* not __GNU_LIBRARY__ */ +extern int getopt_long (int argc, char *const *argv, const char *shortopts, + const struct option *longopts, int *longind); +extern int getopt_long_only (int argc, char *const *argv, + const char *shortopts, + const struct option *longopts, int *longind); + +/* Internal only. Users should not call this directly. */ +extern int _getopt_internal (int argc, char *const *argv, + const char *shortopts, + const struct option *longopts, int *longind, + int long_only); +#else /* not __STDC__ */ +extern int getopt (); +extern int getopt_long (); +extern int getopt_long_only (); + +extern int _getopt_internal (); +#endif /* not __STDC__ */ + +#ifdef __cplusplus +} +#endif + +#endif /* _GETOPT_H */ + + +#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) OF((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 +# define MAX_PATH_LEN 1024 /* max pathname length */ +#endif + +#ifndef SEEK_END +# define SEEK_END 2 +#endif + +#ifdef NO_OFF_T + typedef long off_t; + off_t lseek OF((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 force = 0; /* don't ask questions, compress links (-f) */ +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 void treat_stdin OF((void)); +local int get_method OF((int in)); +local void do_exit OF((int exitcode)); + int main OF((int argc, char **argv)); +int (*work) OF((int infile, int outfile)) = unzip; /* function to call */ + +#define strequ(s1, s2) (strcmp((s1),(s2)) == 0) + +/* ======================================================================== */ +int zcat_main (struct FileInfo * i, int argc, char * * argv) +{ + int file_count; /* number of files to precess */ + + 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 + + /* And get to work */ + treat_stdin(); + + do_exit(exit_code); + return exit_code; /* just to avoid lint warning */ +} + +/* ======================================================================== + * Compress or decompress stdin + */ +local void treat_stdin() +{ + ifile_size = -1L; /* convention for unknown size */ + + clear_bufs(); /* clear input and output buffers */ + part_nb = 0; + + method = get_method(ifd); + + if (method < 0) { + do_exit(exit_code); /* error message already emitted */ + } + + (*work)(fileno(stdin), fileno(stdout)); + +} + + +/* ======================================================================== + * Check the magic number of the input file and update ofname if an + * original name was given and to_stdout 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 */ + + /* If --force and --stdout, zcat == cat, so do not complain about + * premature end of file: use try_byte instead of get_byte. + */ + if (force) { + magic[0] = (char)try_byte(); + magic[1] = (char)try_byte(); + /* If try_byte returned EOF, magic[1] == 0xff */ + } else { + 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) { + fprintf(stderr, + "unknown method %d -- get newer version of gzip\n", + method); + exit_code = ERROR; + return -1; + } + work = unzip; + 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; + } +} + + +/* ======================================================================== + * Free all dynamically allocated variables and exit with the given code. + */ +local void do_exit(exitcode) + int exitcode; +{ + static int in_exit = 0; + + if (in_exit) exit(exitcode); + in_exit = 1; + FREE(inbuf); + FREE(outbuf); + FREE(d_buf); + FREE(window); +#ifndef MAXSEG_64K + FREE(tab_prefix); +#else + FREE(tab_prefix0); + FREE(tab_prefix1); +#endif + exit(exitcode); +} + +/* ======================================================================== + * Signal and error handler. + */ +RETSIGTYPE abort_gzip() +{ + do_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. + */ + +#ifdef RCSID +static char rcsid[] = "$Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $"; +#endif + +/* #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; + + 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) { + error("out of memory"); + } else if (res != 0) { + error("invalid compressed data--format violated"); + } + + } else { + error("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)) { + error("invalid compressed data--crc error"); + } + if (orig_len != (ulg)bytes_out) { + error("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. + */ + +#ifdef RCSID +static char rcsid[] = "$Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $"; +#endif + +#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 + +extern 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() +{ + 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(); + } + 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; + + 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); + + 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; + voidp buf; + unsigned cnt; +{ + unsigned n; + + while ((n = write(fd, buf, cnt)) != cnt) { + if (n == (unsigned)(-1)) { + write_error(); + } + cnt -= n; + buf = (voidp)((char*)buf+n); + } +} + +#if defined(NO_STRING_H) && !defined(STDC_HEADERS) + +/* Provide missing strspn and strcspn functions. */ + +# ifndef __STDC__ +# define const +# endif + +int strspn OF((const char *s, const char *accept)); +int strcspn OF((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 error(m) + char *m; +{ + fprintf(stderr, "\n%s\n", m); + abort_gzip(); +} + +void warn(a, b) + char *a, *b; /* message strings juxtaposed in output */ +{ + WARN((stderr, "warning: %s%s\n", a, b)); +} + +void read_error() +{ + fprintf(stderr, "\n"); + if (errno != 0) { + perror(""); + } else { + fprintf(stderr, "unexpected end of file\n"); + } + abort_gzip(); +} + +void write_error() +{ + fprintf(stderr, "\n"); + perror(""); + abort_gzip(); +} + + +/* ======================================================================== + * Semi-safe malloc -- never returns NULL. + */ +voidp xmalloc (size) + unsigned size; +{ + voidp cp = (voidp)malloc (size); + + if (cp == NULL) error("out of memory"); + return cp; +} + +/* ======================================================================== + * Table of CRC-32's of all single-byte values (made by makecrc.c) + */ +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. + */ + +#ifdef RCSID +static char rcsid[] = "$Id: zcat.c,v 1.1 1999/10/05 16:24:56 andersen Exp $"; +#endif + +#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 OF((unsigned *, unsigned, unsigned, ush *, ush *, + struct huft **, int *)); +int huft_free OF((struct huft *)); +int inflate_codes OF((struct huft *, struct huft *, int, int)); +int inflate_stored OF((void)); +int inflate_fixed OF((void)); +int inflate_dynamic OF((void)); +int inflate_block OF((int *)); +int inflate OF((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; +} |