gzip.c

CZip和CUnzip的源代码

/* 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.
 */

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};

/* 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: gzip.c,v 0.24 1993/06/24 10:52:07 jloup Exp $";
#endif

#include <ctype.h>
#include <sys/types.h>
#include <signal.h>
#include <sys/stat.h>
#include <errno.h>

#include "tailor.h"
#include "gzip.h"
#include "lzw.h"
#include "revision.h"
#include "getopt.h"

		/* configuration */

#ifdef NO_TIME_H
#  include <sys/time.h>
#else
#  include <time.h>
#endif

#ifndef NO_FCNTL_H
#  include <fcntl.h>
#endif

#ifdef HAVE_UNISTD_H
#  include <unistd.h>
#endif

#if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
#  include <stdlib.h>
#else
   extern int errno;
#endif

#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

#ifndef NO_UTIME
#  ifndef NO_UTIME_H
#    include <utime.h>
#    define TIME_OPT "UTIME"
#  else
#    ifdef HAVE_SYS_UTIME_H
#      include <sys/utime.h>
#      define TIME_OPT "SYS_UTIME"
#    else
       struct utimbuf {
         time_t actime;
         time_t modtime;
       };
#      define TIME_OPT ""
#    endif
#  endif
#else
#  define TIME_OPT "NO_UTIME"
#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

/* Separator for file name parts (see shorten_name()) */
#ifdef NO_MULTIPLE_DOTS
#  define PART_SEP "-"
#else
#  define PART_SEP "."
#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 ascii = 0;        /* convert end-of-lines to local OS conventions */
int to_stdout = 0;    /* output to stdout (-c) */
int decompress = 0;   /* decompress (-d) */
int force = 0;        /* don't ask questions, compress links (-f) */
int no_name = -1;     /* don't save or restore the original file name */
int no_time = -1;     /* don't save or restore the original file time */
int recursive = 0;    /* recurse through directories (-r) */
int list = 0;         /* list the file contents (-l) */
int verbose = 0;      /* be verbose (-v) */
int quiet = 0;        /* be very quiet (-q) */
int do_lzw = 0;       /* generate output compatible with old compress (-Z) */
int test = 0;         /* test .gz file integrity */
int foreground;       /* set if program run in foreground */
char *progname;       /* program name */
int maxbits = BITS;   /* max bits per code for LZW */
int method = DEFLATED;/* compression method */
int level = 6;        /* compression level */
int exit_code = OK;   /* program exit code */
int save_orig_name;   /* set if original name must be saved */
int last_member;      /* set for .zip and .Z files */
int part_nb;          /* number of parts in .gz file */
long time_stamp;      /* original time stamp (modification time) */
long ifile_size;      /* input file size, -1 for devices (debug only) */
char *env;            /* contents of GZIP env variable */
char **args = NULL;   /* argv pointer if GZIP env variable defined */
char z_suffix[MAX_SUFFIX+1]; /* default suffix (can be set with --suffix) */
int  z_len;           /* strlen(z_suffix) */

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 */
char ifname[MAX_PATH_LEN]; /* input file name */
char ofname[MAX_PATH_LEN]; /* output file name */
int  remove_ofname = 0;	   /* remove output file on error */
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 */

struct option longopts[] =
{
 /* { name  has_arg  *flag  val } */
    {"ascii",      0, 0, 'a'}, /* ascii text mode */
    {"to-stdout",  0, 0, 'c'}, /* write output on standard output */
    {"stdout",     0, 0, 'c'}, /* write output on standard output */
    {"decompress", 0, 0, 'd'}, /* decompress */
    {"uncompress", 0, 0, 'd'}, /* decompress */
 /* {"encrypt",    0, 0, 'e'},    encrypt */
    {"force",      0, 0, 'f'}, /* force overwrite of output file */
    {"help",       0, 0, 'h'}, /* give help */
 /* {"pkzip",      0, 0, 'k'},    force output in pkzip format */
    {"list",       0, 0, 'l'}, /* list .gz file contents */
    {"license",    0, 0, 'L'}, /* display software license */
    {"no-name",    0, 0, 'n'}, /* don't save or restore original name & time */
    {"name",       0, 0, 'N'}, /* save or restore original name & time */
    {"quiet",      0, 0, 'q'}, /* quiet mode */
    {"silent",     0, 0, 'q'}, /* quiet mode */
    {"recursive",  0, 0, 'r'}, /* recurse through directories */
    {"suffix",     1, 0, 'S'}, /* use given suffix instead of .gz */
    {"test",       0, 0, 't'}, /* test compressed file integrity */
    {"no-time",    0, 0, 'T'}, /* don't save or restore the time stamp */
    {"verbose",    0, 0, 'v'}, /* verbose mode */
    {"version",    0, 0, 'V'}, /* display version number */
    {"fast",       0, 0, '1'}, /* compress faster */
    {"best",       0, 0, '9'}, /* compress better */
    {"lzw",        0, 0, 'Z'}, /* make output compatible with old compress */
    {"bits",       1, 0, 'b'}, /* max number of bits per code (implies -Z) */
    { 0, 0, 0, 0 }
};

/* local functions */

local void usage        OF((void));
local void help         OF((void));
local void license      OF((void));
local void version      OF((void));
local void treat_stdin  OF((void));
local void treat_file   OF((char *iname));
local int create_outfile OF((void));
local int  do_stat      OF((char *name, struct stat *sbuf));
local char *get_suffix  OF((char *name));
local int  get_istat    OF((char *iname, struct stat *sbuf));
local int  make_ofname  OF((void));
local int  same_file    OF((struct stat *stat1, struct stat *stat2));
local int name_too_long OF((char *name, struct stat *statb));
local void shorten_name  OF((char *name));
local int  get_method   OF((int in));
local void do_list      OF((int ifd, int method));
local int  check_ofname OF((void));
local void copy_stat    OF((struct stat *ifstat));
local void do_exit      OF((int exitcode));
      int main          OF((int argc, char **argv));
int (*work) OF((int infile, int outfile)) = zip; /* function to call */

#ifndef NO_DIR
local void treat_dir    OF((char *dir));
#endif
#ifndef NO_UTIME
local void reset_times  OF((char *name, struct stat *statb));
#endif

#define strequ(s1, s2) (strcmp((s1),(s2)) == 0)

/* ======================================================================== */
local void usage()
{
    fprintf(stderr, "usage: %s [-%scdfhlLnN%stvV19] [-S suffix] [file ...]\n",
	    progname,
#if O_BINARY
	    "a",
#else
	    "",
#endif
#ifdef NO_DIR
	    ""
#else
	    "r"
#endif
	    );
}

/* ======================================================================== */
local void help()
{
    static char  *help_msg[] = {
#if O_BINARY
 " -a --ascii       ascii text; convert end-of-lines using local conventions",
#endif
 " -c --stdout      write on standard output, keep original files unchanged",
 " -d --decompress  decompress",
/* -e --encrypt     encrypt */
 " -f --force       force overwrite of output file and compress links",
 " -h --help        give this help",
/* -k --pkzip       force output in pkzip format */
 " -l --list        list compressed file contents",
 " -L --license     display software license",
#ifdef UNDOCUMENTED
 " -m --no-time     do not save or restore the original modification time",
 " -M --time        save or restore the original modification time",
#endif
 " -n --no-name     do not save or restore the original name and time stamp",
 " -N --name        save or restore the original name and time stamp",
 " -q --quiet       suppress all warnings",
#ifndef NO_DIR
 " -r --recursive   operate recursively on directories",
#endif
 " -S .suf  --suffix .suf     use suffix .suf on compressed files",
 " -t --test        test compressed file integrity",
 " -v --verbose     verbose mode",
 " -V --version     display version number",
 " -1 --fast        compress faster",
 " -9 --best        compress better",
#ifdef LZW
 " -Z --lzw         produce output compatible with old compress",
 " -b --bits maxbits   max number of bits per code (implies -Z)",
#endif
 " file...          files to (de)compress. If none given, use standard input.",
  0};
    char **p = help_msg;

    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);
    usage();
    while (*p) fprintf(stderr, "%s\n", *p++);
}

/* ======================================================================== */
local void license()
{
    char **p = license_msg;

    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);
    while (*p) fprintf(stderr, "%s\n", *p++);
}

/* ======================================================================== */
local void version()
{
    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);

    fprintf(stderr, "Compilation options:\n%s %s ", DIR_OPT, TIME_OPT);
#ifdef STDC_HEADERS
    fprintf(stderr, "STDC_HEADERS ");
#endif
#ifdef HAVE_UNISTD_H
    fprintf(stderr, "HAVE_UNISTD_H ");
#endif
#ifdef NO_MEMORY_H
    fprintf(stderr, "NO_MEMORY_H ");
#endif
#ifdef NO_STRING_H
    fprintf(stderr, "NO_STRING_H ");
#endif
#ifdef NO_SYMLINK
    fprintf(stderr, "NO_SYMLINK ");
#endif