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-rw-r--r--usr/gzip/gzip.c1215
1 files changed, 1215 insertions, 0 deletions
diff --git a/usr/gzip/gzip.c b/usr/gzip/gzip.c
new file mode 100644
index 0000000..d0c7e00
--- /dev/null
+++ b/usr/gzip/gzip.c
@@ -0,0 +1,1215 @@
+/* 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 1.3 2005/02/12 21:03:28 olh 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 "revision.h"
+
+#include <time.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include <utime.h>
+
+typedef void (*sig_type) OF((int));
+
+#define RW_USER (S_IRUSR | S_IWUSR) /* creation mode for open() */
+
+#ifndef MAX_PATH_LEN
+# define MAX_PATH_LEN 1024 /* max pathname length */
+#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);
+DECLARE(ush, tab_prefix, 1L<<BITS);
+
+ /* local variables */
+
+#ifndef SUPPORT_ZIP
+#define decompress 1
+#else
+int level = 6; /* compression level */
+#endif
+
+int to_stdout; /* output to stdout (-c) */
+#ifdef decompress
+int decompress_wanted;
+#else
+int decompress; /* decompress (-d) */
+#define decompress_wanted decompress
+#endif
+int force; /* 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 verbose; /* be verbose (-v) */
+int quiet; /* be very quiet (-q) */
+int test; /* test .gz file integrity */
+int foreground; /* set if program run in foreground */
+char *progname; /* program name */
+int method = DEFLATED;/* compression method */
+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 */
+time_t 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 header_bytes; /* number of bytes in gzip header */
+long bytes_in; /* number of input bytes */
+long bytes_out; /* number of output bytes */
+long total_in; /* input bytes for all files */
+long total_out; /* output bytes for all files */
+char ifname[MAX_PATH_LEN]; /* input file name */
+char ofname[MAX_PATH_LEN]; /* output file name */
+int remove_ofname; /* 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 */
+
+/* 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((void));
+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))
+#ifdef SUPPORT_ZIP
+ = zip; /* function to call */
+#else
+ = unzip;
+#endif
+local void reset_times OF((char *name, struct stat *statb));
+
+#define strequ(s1, s2) (strcmp((s1),(s2)) == 0)
+
+/* ======================================================================== */
+local void usage()
+{
+ fprintf(stderr, "usage: %s [-cdfhlLnNtvV19] [-S suffix] [file ...]\n",
+ progname);
+}
+
+/* ======================================================================== */
+local void help()
+{
+ static char *help_msg[] = {
+ " -c --stdout write on standard output, keep original files unchanged",
+ " -d --decompress decompress",
+ " -f --force force overwrite of output file and compress links",
+ " -h --help give this help",
+ " -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",
+ " -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",
+#ifdef SUPPORT_ZIP
+ " -1 --fast compress faster",
+ " -9 --best compress better",
+ " file... files to (de)compress. If none given, use standard input.",
+#else
+ " file... files to decompress. If none given, use standard input.",
+#endif
+ 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: UTIME STDC_HEADERS"
+#ifndef SUPPORT_ZIP
+ " DECOMPRESS_ONLY"
+#endif
+ "\n");
+}
+
+/* ======================================================================== */
+int main (argc, argv)
+ int argc;
+ char **argv;
+{
+ int file_count; /* number of files to precess */
+ int optc; /* current option */
+
+ progname = basename(argv[0]);
+
+ /* Add options in GZIP environment variable if there is one */
+ env = add_envopt(&argc, &argv, OPTIONS_VAR);
+ if (env != NULL) args = argv;
+
+ foreground = sysv_signal(SIGINT, SIG_IGN) != SIG_IGN;
+ if (foreground) {
+ (void) sysv_signal(SIGINT, (sig_type)abort_gzip);
+ }
+#ifdef SIGTERM
+ if (sysv_signal(SIGTERM, SIG_IGN) != SIG_IGN) {
+ (void) sysv_signal(SIGTERM, (sig_type)abort_gzip);
+ }
+#endif
+#ifdef SIGHUP
+ if (sysv_signal(SIGHUP, SIG_IGN) != SIG_IGN) {
+ (void) sysv_signal(SIGHUP, (sig_type)abort_gzip);
+ }
+#endif
+
+#ifndef GNU_STANDARD
+ /* For compatibility with old compress, use program name as an option.
+ * If you compile with -DGNU_STANDARD, this program will behave as
+ * gzip even if it is invoked under the name gunzip or zcat.
+ *
+ * Systems which do not support links can still use -d or -dc.
+ * Ignore an .exe extension for MSDOS, OS/2 and VMS.
+ */
+ if ( strncmp(progname, "un", 2) == 0 /* ungzip, uncompress */
+ || strncmp(progname, "gun", 3) == 0) { /* gunzip */
+ decompress_wanted = 1;
+ }
+ if (strequ(progname+1, "cat") /* zcat, pcat, gcat */
+ || strequ(progname, "gzcat")) { /* gzcat */
+ decompress_wanted = 1;
+ to_stdout = 1;
+ }
+#endif
+
+ strncpy(z_suffix, Z_SUFFIX, sizeof(z_suffix)-1);
+ z_len = strlen(z_suffix);
+
+ while ((optc = getopt(argc, argv, "cdfhH?LmMnNqrS:tvV123456789")) != EOF) {
+ switch (optc) {
+ case 'c':
+ to_stdout = 1; break;
+ case 'd':
+ decompress_wanted = 1;
+ break;
+ case 'f':
+ force++; break;
+ case 'h': case 'H': case '?':
+ help(); do_exit(OK); break;
+ case 'L':
+ license(); do_exit(OK); break;
+ case 'm': /* undocumented, may change later */
+ no_time = 1; break;
+ case 'M': /* undocumented, may change later */
+ no_time = 0; break;
+ case 'n':
+ no_name = no_time = 1; break;
+ case 'N':
+ no_name = no_time = 0; break;
+ case 'q':
+ quiet = 1; verbose = 0; break;
+ case 'S':
+ z_len = strlen(optarg);
+ strcpy(z_suffix, optarg);
+ break;
+ case 't':
+ test = to_stdout = 1;
+ decompress_wanted = 1;
+ break;
+ case 'v':
+ verbose++; quiet = 0; break;
+ case 'V':
+ version(); do_exit(OK); break;
+#ifdef SUPPORT_ZIP
+ case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ level = optc - '0';
+ break;
+#endif
+ default:
+ /* Error message already emitted by getopt_long. */
+ usage();
+ do_exit(ERROR);
+ }
+ } /* loop on all arguments */
+
+#ifndef SUPPORT_ZIP
+ if (!decompress_wanted) {
+ fprintf(stderr, "%s: this version does not support compression\n",
+ progname);
+ do_exit(ERROR);
+ }
+#endif
+
+ /* By default, save name and timestamp on compression but do not
+ * restore them on decompression.
+ */
+ if (no_time < 0) no_time = decompress;
+ if (no_name < 0) no_name = decompress;
+
+ file_count = argc - optind;
+
+ if ((z_len == 0 && !decompress) || z_len > MAX_SUFFIX) {
+ fprintf(stderr, "%s: incorrect suffix '%s'\n",
+ progname, optarg);
+ do_exit(ERROR);
+ }
+
+ /* 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);
+ ALLOC(ush, tab_prefix, 1L<<BITS);
+
+ /* And get to work */
+ if (file_count != 0) {
+ while (optind < argc) {
+ treat_file(argv[optind++]);
+ }
+ } else { /* Standard input */
+ treat_stdin();
+ }
+ do_exit(exit_code);
+ return exit_code; /* just to avoid lint warning */
+}
+
+/* ========================================================================
+ * Compress or decompress stdin
+ */
+local void treat_stdin()
+{
+ if (!force &&
+ isatty(fileno((FILE *)(decompress ? stdin : stdout)))) {
+ /* Do not send compressed data to the terminal or read it from
+ * the terminal. We get here when user invoked the program
+ * without parameters, so be helpful. According to the GNU standards:
+ *
+ * If there is one behavior you think is most useful when the output
+ * is to a terminal, and another that you think is most useful when
+ * the output is a file or a pipe, then it is usually best to make
+ * the default behavior the one that is useful with output to a
+ * terminal, and have an option for the other behavior.
+ *
+ * Here we use the --force option to get the other behavior.
+ */
+ fprintf(stderr,
+ "%s: compressed data not %s a terminal. Use -f to force %scompression.\n",
+ progname, decompress ? "read from" : "written to",
+ decompress ? "de" : "");
+ fprintf(stderr,"For help, type: %s -h\n", progname);
+ do_exit(ERROR);
+ }
+
+ strcpy(ifname, "stdin");
+ strcpy(ofname, "stdout");
+
+ /* Get the time stamp on the input file. */
+ time_stamp = 0; /* time unknown by default */
+
+ if (!no_time) {
+ if (fstat(fileno(stdin), &istat) != 0) {
+ error("fstat(stdin)");
+ }
+ time_stamp = istat.st_mtime;
+ }
+ ifile_size = -1L; /* convention for unknown size */
+
+ clear_bufs(); /* clear input and output buffers */
+ to_stdout = 1;
+ part_nb = 0;
+
+ if (decompress) {
+ method = get_method();
+ if (method < 0) {
+ do_exit(exit_code); /* error message already emitted */
+ }
+ }
+
+ /* Actually do the compression/decompression. Loop over zipped members.
+ */
+ for (;;) {
+ if ((*work)(fileno(stdin), fileno(stdout)) != OK) return;
+
+ if (!decompress || last_member || inptr == insize) break;
+ /* end of file */
+
+ method = get_method();
+ if (method < 0) return; /* error message already emitted */
+ bytes_out = 0; /* required for length check */
+ }
+
+ if (verbose) {
+ if (test) {
+ fprintf(stderr, " OK\n");
+
+ } else if (!decompress) {
+ display_ratio(bytes_in-(bytes_out-header_bytes), bytes_in, stderr);
+ fprintf(stderr, "\n");
+#ifdef DISPLAY_STDIN_RATIO
+ } else {
+ display_ratio(bytes_out-(bytes_in-header_bytes), bytes_out,stderr);
+ fprintf(stderr, "\n");
+#endif
+ }
+ }
+}
+
+/* ========================================================================
+ * Compress or decompress the given file
+ */
+local void treat_file(iname)
+ char *iname;
+{
+ /* Accept "-" as synonym for stdin */
+ if (strequ(iname, "-")) {
+ int cflag = to_stdout;
+ treat_stdin();
+ to_stdout = cflag;
+ return;
+ }
+
+ /* Check if the input file is present, set ifname and istat: */
+ if (get_istat(iname, &istat) != OK) return;
+
+ /* If the input name is that of a directory, recurse or ignore: */
+ if (S_ISDIR(istat.st_mode)) {
+ WARN((stderr,"%s: %s is a directory -- ignored\n", progname, ifname));
+ return;
+ }
+ if (!S_ISREG(istat.st_mode)) {
+ WARN((stderr,
+ "%s: %s is not a directory or a regular file - ignored\n",
+ progname, ifname));
+ return;
+ }
+ if (istat.st_nlink > 1 && !to_stdout && !force) {
+ WARN((stderr, "%s: %s has %d other link%c -- unchanged\n",
+ progname, ifname,
+ (int)istat.st_nlink - 1, istat.st_nlink > 2 ? 's' : ' '));
+ return;
+ }
+
+ ifile_size = istat.st_size;
+ time_stamp = no_time ? 0 : istat.st_mtime;
+
+ /* Generate output file name. For -r and (-t or -l), skip files
+ * without a valid gzip suffix (check done in make_ofname).
+ */
+ if (to_stdout && !test) {
+ strcpy(ofname, "stdout");
+
+ } else if (make_ofname() != OK) {
+ return;
+ }
+
+ /* Open the input file and determine compression method. The mode
+ * parameter is ignored but required by some systems (VMS) and forbidden
+ * on other systems (MacOS).
+ */
+ ifd = open(ifname, !decompress ? O_RDONLY : O_RDONLY,
+ RW_USER);
+ if (ifd == -1) {
+ fprintf(stderr, "%s: ", progname);
+ perror(ifname);
+ exit_code = ERROR;
+ return;
+ }
+ clear_bufs(); /* clear input and output buffers */
+ part_nb = 0;
+
+ if (decompress) {
+ method = get_method(); /* updates ofname if original given */
+ if (method < 0) {
+ close(ifd);
+ return; /* error message already emitted */
+ }
+ }
+
+ /* If compressing to a file, check if ofname is not ambiguous
+ * because the operating system truncates names. Otherwise, generate
+ * a new ofname and save the original name in the compressed file.
+ */
+ if (to_stdout) {
+ ofd = fileno(stdout);
+ /* keep remove_ofname as zero */
+ } else {
+ if (create_outfile() != OK) return;
+
+ if (!decompress && save_orig_name && !verbose && !quiet) {
+ fprintf(stderr, "%s: %s compressed to %s\n",
+ progname, ifname, ofname);
+ }
+ }
+ /* Keep the name even if not truncated except with --no-name: */
+ if (!save_orig_name) save_orig_name = !no_name;
+
+ if (verbose) {
+ fprintf(stderr, "%s:\t%s", ifname, (int)strlen(ifname) >= 15 ?
+ "" : ((int)strlen(ifname) >= 7 ? "\t" : "\t\t"));
+ }
+
+ /* Actually do the compression/decompression. Loop over zipped members.
+ */
+ for (;;) {
+ if ((*work)(ifd, ofd) != OK) {
+ method = -1; /* force cleanup */
+ break;
+ }
+ if (!decompress || last_member || inptr == insize) break;
+ /* end of file */
+
+ method = get_method();
+ if (method < 0) break; /* error message already emitted */
+ bytes_out = 0; /* required for length check */
+ }
+
+ close(ifd);
+ if (!to_stdout && close(ofd)) {
+ write_error();
+ }
+ if (method == -1) {
+ if (!to_stdout) unlink (ofname);
+ return;
+ }
+ /* Display statistics */
+ if(verbose) {
+ if (test) {
+ fprintf(stderr, " OK");
+ } else if (decompress) {
+ display_ratio(bytes_out-(bytes_in-header_bytes), bytes_out,stderr);
+ } else {
+ display_ratio(bytes_in-(bytes_out-header_bytes), bytes_in, stderr);
+ }
+ if (!test && !to_stdout) {
+ fprintf(stderr, " -- replaced with %s", ofname);
+ }
+ fprintf(stderr, "\n");
+ }
+ /* Copy modes, times, ownership, and remove the input file */
+ if (!to_stdout) {
+ copy_stat(&istat);
+ }
+}
+
+/* ========================================================================
+ * Create the output file. Return OK or ERROR.
+ * Try several times if necessary to avoid truncating the z_suffix. For
+ * example, do not create a compressed file of name "1234567890123."
+ * Sets save_orig_name to true if the file name has been truncated.
+ * IN assertions: the input file has already been open (ifd is set) and
+ * ofname has already been updated if there was an original name.
+ * OUT assertions: ifd and ofd are closed in case of error.
+ */
+local int create_outfile()
+{
+ struct stat ostat; /* stat for ofname */
+ int flags = O_WRONLY | O_CREAT | O_EXCL;
+
+ for (;;) {
+ /* Make sure that ofname is not an existing file */
+ if (check_ofname() != OK) {
+ close(ifd);
+ return ERROR;
+ }
+ /* Create the output file */
+ remove_ofname = 1;
+ ofd = open(ofname, flags, RW_USER);
+ if (ofd == -1) {
+ perror(ofname);
+ close(ifd);
+ exit_code = ERROR;
+ return ERROR;
+ }
+
+ /* Check for name truncation on new file (1234567890123.gz) */
+ if (fstat(ofd, &ostat) != 0) {
+ fprintf(stderr, "%s: ", progname);
+ perror(ofname);
+ close(ifd); close(ofd);
+ unlink(ofname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+ if (!name_too_long(ofname, &ostat)) return OK;
+
+ if (decompress) {
+ /* name might be too long if an original name was saved */
+ WARN((stderr, "%s: %s: warning, name truncated\n",
+ progname, ofname));
+ return OK;
+ }
+ close(ofd);
+ unlink(ofname);
+ shorten_name(ofname);
+ }
+}
+
+/* ========================================================================
+ * Use lstat if available, except for -c or -f. Use stat otherwise.
+ * This allows links when not removing the original file.
+ */
+local int do_stat(name, sbuf)
+ char *name;
+ struct stat *sbuf;
+{
+ errno = 0;
+ if (!to_stdout && !force) {
+ return lstat(name, sbuf);
+ }
+ return stat(name, sbuf);
+}
+
+/* ========================================================================
+ * Return a pointer to the 'z' suffix of a file name, or NULL. For all
+ * systems, ".gz", ".z", ".Z", ".taz", ".tgz", "-gz", "-z" and "_z" are
+ * accepted suffixes, in addition to the value of the --suffix option.
+ * ".tgz" is a useful convention for tar.z files on systems limited
+ * to 3 characters extensions. On such systems, ".?z" and ".??z" are
+ * also accepted suffixes. For Unix, we do not want to accept any
+ * .??z suffix as indicating a compressed file; some people use .xyz
+ * to denote volume data.
+ * On systems allowing multiple versions of the same file (such as VMS),
+ * this function removes any version suffix in the given name.
+ */
+local char *get_suffix(name)
+ char *name;
+{
+ int nlen, slen;
+ char suffix[MAX_SUFFIX+3]; /* last chars of name, forced to lower case */
+ static char *known_suffixes[] =
+ {z_suffix, ".gz", ".z", ".taz", ".tgz", "-gz", "-z", "_z",
+ NULL};
+ char **suf = known_suffixes;
+
+ if (strequ(z_suffix, "z")) suf++; /* check long suffixes first */
+
+ nlen = strlen(name);
+ if (nlen <= MAX_SUFFIX+2) {
+ strcpy(suffix, name);
+ } else {
+ strcpy(suffix, name+nlen-MAX_SUFFIX-2);
+ }
+ strlwr(suffix);
+ slen = strlen(suffix);
+ do {
+ int s = strlen(*suf);
+ if (slen > s && suffix[slen-s-1] != PATH_SEP
+ && strequ(suffix + slen - s, *suf)) {
+ return name+nlen-s;
+ }
+ } while (*++suf != NULL);
+
+ return NULL;
+}
+
+
+/* ========================================================================
+ * Set ifname to the input file name (with a suffix appended if necessary)
+ * and istat to its stats. For decompression, if no file exists with the
+ * original name, try adding successively z_suffix, .gz, .z, -z and .Z.
+ * For MSDOS, we try only z_suffix and z.
+ * Return OK or ERROR.
+ */
+local int get_istat(iname, sbuf)
+ char *iname;
+ struct stat *sbuf;
+{
+ int ilen; /* strlen(ifname) */
+ static char *suffixes[] = {z_suffix, ".gz", ".z", "-z", ".Z", NULL};
+ char **suf = suffixes;
+ char *s;
+
+ strcpy(ifname, iname);
+
+ /* If input file exists, return OK. */
+ if (do_stat(ifname, sbuf) == 0) return OK;
+
+ if (!decompress || errno != ENOENT) {
+ perror(ifname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+ /* file.ext doesn't exist, try adding a suffix (after removing any
+ * version number for VMS).
+ */
+ s = get_suffix(ifname);
+ if (s != NULL) {
+ perror(ifname); /* ifname already has z suffix and does not exist */
+ exit_code = ERROR;
+ return ERROR;
+ }
+ ilen = strlen(ifname);
+ if (strequ(z_suffix, ".gz")) suf++;
+
+ /* Search for all suffixes */
+ do {
+ s = *suf;
+ strcat(ifname, s);
+ if (do_stat(ifname, sbuf) == 0) return OK;
+ ifname[ilen] = '\0';
+ } while (*++suf != NULL);
+
+ /* No suffix found, complain using z_suffix: */
+ strcat(ifname, z_suffix);
+ perror(ifname);
+ exit_code = ERROR;
+ return ERROR;
+}
+
+/* ========================================================================
+ * Generate ofname given ifname. Return OK, or WARNING if file must be skipped.
+ * Sets save_orig_name to true if the file name has been truncated.
+ */
+local int make_ofname()
+{
+ char *suff; /* ofname z suffix */
+
+ strcpy(ofname, ifname);
+ /* strip a version number if any and get the gzip suffix if present: */
+ suff = get_suffix(ofname);
+
+ if (decompress) {
+ if (suff == NULL) {
+ /* Whith -t or -l, try all files (even without .gz suffix)
+ * except with -r (behave as with just -dr).
+ */
+ if (test) return OK;
+
+ /* Avoid annoying messages with -r */
+ if (verbose || !quiet) {
+ WARN((stderr,"%s: %s: unknown suffix -- ignored\n",
+ progname, ifname));
+ }
+ return WARNING;
+ }
+ /* Make a special case for .tgz and .taz: */
+ strlwr(suff);
+ if (strequ(suff, ".tgz") || strequ(suff, ".taz")) {
+ strcpy(suff, ".tar");
+ } else {
+ *suff = '\0'; /* strip the z suffix */
+ }
+ /* ofname might be changed later if infile contains an original name */
+
+ } else if (suff != NULL) {
+ /* Avoid annoying messages with -r (see treat_dir()) */
+ if (verbose || !quiet) {
+ fprintf(stderr, "%s: %s already has %s suffix -- unchanged\n",
+ progname, ifname, suff);
+ }
+ if (exit_code == OK) exit_code = WARNING;
+ return WARNING;
+ } else {
+ save_orig_name = 0;
+ strcat(ofname, z_suffix);
+
+ } /* decompress ? */
+ return OK;
+}
+
+
+/* ========================================================================
+ * 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()
+{
+ uch flags; /* compression flags */
+ char magic[2]; /* magic header */
+ ulg stamp; /* time stamp */
+
+ /* If --force and --stdout, zcat == cat, so do not complain about
+ * premature end of file: use try_byte instead of get_byte.
+ */
+ if (force && to_stdout) {
+ 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
+ || memcmp(magic, OLD_GZIP_MAGIC, 2) == 0) {
+
+ method = (int)get_byte();
+ if (method != DEFLATED) {
+ fprintf(stderr,
+ "%s: %s: unknown method %d -- get newer version of gzip\n",
+ progname, ifname, method);
+ exit_code = ERROR;
+ return -1;
+ }
+ work = unzip;
+ flags = (uch)get_byte();
+
+ if ((flags & ENCRYPTED) != 0) {
+ fprintf(stderr,
+ "%s: %s is encrypted -- get newer version of gzip\n",
+ progname, ifname);
+ exit_code = ERROR;
+ return -1;
+ }
+ if ((flags & CONTINUATION) != 0) {
+ fprintf(stderr,
+ "%s: %s is a a multi-part gzip file -- get newer version of gzip\n",
+ progname, ifname);
+ exit_code = ERROR;
+ if (force <= 1) return -1;
+ }
+ if ((flags & RESERVED) != 0) {
+ fprintf(stderr,
+ "%s: %s has flags 0x%x -- get newer version of gzip\n",
+ progname, ifname, flags);
+ exit_code = ERROR;
+ if (force <= 1) return -1;
+ }
+ stamp = (ulg)get_byte();
+ stamp |= ((ulg)get_byte()) << 8;
+ stamp |= ((ulg)get_byte()) << 16;
+ stamp |= ((ulg)get_byte()) << 24;
+ if (stamp != 0 && !no_time) time_stamp = stamp;
+
+ (void)get_byte(); /* Ignore extra flags for the moment */
+ (void)get_byte(); /* Ignore OS type for the moment */
+
+ if ((flags & CONTINUATION) != 0) {
+ unsigned part = (unsigned)get_byte();
+ part |= ((unsigned)get_byte())<<8;
+ if (verbose) {
+ fprintf(stderr,"%s: %s: part number %u\n",
+ progname, ifname, part);
+ }
+ }
+ if ((flags & EXTRA_FIELD) != 0) {
+ unsigned len = (unsigned)get_byte();
+ len |= ((unsigned)get_byte())<<8;
+ if (verbose) {
+ fprintf(stderr,"%s: %s: extra field of %u bytes ignored\n",
+ progname, ifname, len);
+ }
+ while (len--) (void)get_byte();
+ }
+
+ /* Get original file name if it was truncated */
+ if ((flags & ORIG_NAME) != 0) {
+ if (no_name || to_stdout || part_nb > 1) {
+ /* Discard the old name */
+ char c; /* dummy used for NeXTstep 3.0 cc optimizer bug */
+ do {c=get_byte();} while (c != 0);
+ } else {
+ /* Copy the base name. Keep a directory prefix intact. */
+ char *p = basename(ofname);
+ for (;;) {
+ *p = (char)get_char();
+ if (*p++ == '\0') break;
+ if (p >= ofname+sizeof(ofname)) {
+ error("corrupted input -- file name too large");
+ }
+ }
+ } /* no_name || to_stdout */
+ } /* ORIG_NAME */
+
+ /* 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 */
+ }
+ } else if (force && to_stdout) { /* pass input unchanged */
+ method = STORED;
+ work = copy;
+ inptr = 0;
+ last_member = 1;
+ }
+ if (method >= 0) return method;
+
+ if (part_nb == 1) {
+ fprintf(stderr, "\n%s: %s: not in gzip format\n", progname, ifname);
+ exit_code = ERROR;
+ return -1;
+ } else {
+ WARN((stderr, "\n%s: %s: decompression OK, trailing garbage ignored\n",
+ progname, ifname));
+ return -2;
+ }
+}
+
+
+/* ========================================================================
+ * Return true if the two stat structures correspond to the same file.
+ */
+local int same_file(stat1, stat2)
+ struct stat *stat1;
+ struct stat *stat2;
+{
+ return stat1->st_ino == stat2->st_ino
+ && stat1->st_dev == stat2->st_dev
+#ifdef NO_ST_INO
+ /* Can't rely on st_ino and st_dev, use other fields: */
+ && stat1->st_mode == stat2->st_mode
+ && stat1->st_uid == stat2->st_uid
+ && stat1->st_gid == stat2->st_gid
+ && stat1->st_size == stat2->st_size
+ && stat1->st_atime == stat2->st_atime
+ && stat1->st_mtime == stat2->st_mtime
+ && stat1->st_ctime == stat2->st_ctime
+#endif
+ ;
+}
+
+/* ========================================================================
+ * Return true if a file name is ambiguous because the operating system
+ * truncates file names.
+ */
+local int name_too_long(name, statb)
+ char *name; /* file name to check */
+ struct stat *statb; /* stat buf for this file name */
+{
+ int s = strlen(name);
+ char c = name[s-1];
+ struct stat tstat; /* stat for truncated name */
+ int res;
+
+ tstat = *statb; /* Just in case OS does not fill all fields */
+ name[s-1] = '\0';
+ res = stat(name, &tstat) == 0 && same_file(statb, &tstat);
+ name[s-1] = c;
+ Trace((stderr, " too_long(%s) => %d\n", name, res));
+ return res;
+}
+
+/* ========================================================================
+ * Shorten the given name by one character, or replace a .tar extension
+ * with .tgz. Truncate the last part of the name which is longer than
+ * MIN_PART characters: 1234.678.012.gz -> 123.678.012.gz. If the name
+ * has only parts shorter than MIN_PART truncate the longest part.
+ * For decompression, just remove the last character of the name.
+ *
+ * IN assertion: for compression, the suffix of the given name is z_suffix.
+ */
+local void shorten_name(name)
+ char *name;
+{
+ int len; /* length of name without z_suffix */
+ char *trunc = NULL; /* character to be truncated */
+ int plen; /* current part length */
+ int min_part = MIN_PART; /* current minimum part length */
+ char *p;
+
+ len = strlen(name);
+ if (decompress) {
+ if (len <= 1) error("name too short");
+ name[len-1] = '\0';
+ return;
+ }
+ p = get_suffix(name);
+ if (p == NULL) error("can't recover suffix\n");
+ *p = '\0';
+ save_orig_name = 1;
+
+ /* compress 1234567890.tar to 1234567890.tgz */
+ if (len > 4 && strequ(p-4, ".tar")) {
+ strcpy(p-4, ".tgz");
+ return;
+ }
+ /* Try keeping short extensions intact:
+ * 1234.678.012.gz -> 123.678.012.gz
+ */
+ do {
+ p = strrchr(name, PATH_SEP);
+ p = p ? p+1 : name;
+ while (*p) {
+ plen = strcspn(p, ".");
+ p += plen;
+ if (plen > min_part) trunc = p-1;
+ if (*p) p++;
+ }
+ } while (trunc == NULL && --min_part != 0);
+
+ if (trunc != NULL) {
+ do {
+ trunc[0] = trunc[1];
+ } while (*trunc++);
+ trunc--;
+ } else {
+ trunc = strrchr(name, '.');
+ if (trunc == NULL) error("internal error in shorten_name");
+ if (trunc[1] == '\0') trunc--; /* force truncation */
+ }
+ strcpy(trunc, z_suffix);
+}
+
+/* ========================================================================
+ * If compressing to a file, check if ofname is not ambiguous
+ * because the operating system truncates names. Otherwise, generate
+ * a new ofname and save the original name in the compressed file.
+ * If the compressed file already exists, ask for confirmation.
+ * The check for name truncation is made dynamically, because different
+ * file systems on the same OS might use different truncation rules (on SVR4
+ * s5 truncates to 14 chars and ufs does not truncate).
+ * This function returns -1 if the file must be skipped, and
+ * updates save_orig_name if necessary.
+ * IN assertions: save_orig_name is already set if ofname has been
+ * already truncated because of NO_MULTIPLE_DOTS. The input file has
+ * already been open and istat is set.
+ */
+local int check_ofname()
+{
+ struct stat ostat; /* stat for ofname */
+
+#ifdef ENAMETOOLONG
+ /* Check for strictly conforming Posix systems (which return ENAMETOOLONG
+ * instead of silently truncating filenames).
+ */
+ errno = 0;
+ while (stat(ofname, &ostat) != 0) {
+ if (errno != ENAMETOOLONG) return 0; /* ofname does not exist */
+ shorten_name(ofname);
+ }
+#else
+ if (stat(ofname, &ostat) != 0) return 0;
+#endif
+ /* Check for name truncation on existing file. Do this even on systems
+ * defining ENAMETOOLONG, because on most systems the strict Posix
+ * behavior is disabled by default (silent name truncation allowed).
+ */
+ if (!decompress && name_too_long(ofname, &ostat)) {
+ shorten_name(ofname);
+ if (stat(ofname, &ostat) != 0) return 0;
+ }
+
+ /* Check that the input and output files are different (could be
+ * the same by name truncation or links).
+ */
+ if (same_file(&istat, &ostat)) {
+ if (strequ(ifname, ofname)) {
+ fprintf(stderr, "%s: %s: cannot %scompress onto itself\n",
+ progname, ifname, decompress ? "de" : "");
+ } else {
+ fprintf(stderr, "%s: %s and %s are the same file\n",
+ progname, ifname, ofname);
+ }
+ exit_code = ERROR;
+ return ERROR;
+ }
+ /* Ask permission to overwrite the existing file */
+ if (!force) {
+#if 0
+ char response[80];
+ strcpy(response,"n");
+ fprintf(stderr, "%s: %s already exists;", progname, ofname);
+ if (foreground && isatty(fileno(stdin))) {
+ fprintf(stderr, " do you wish to overwrite (y or n)? ");
+ (void)fgets(response, sizeof(response)-1, stdin);
+ }
+ if (tolow(*response) != 'y') {
+ fprintf(stderr, "\tnot overwritten\n");
+#endif
+ if (exit_code == OK) exit_code = WARNING;
+ return ERROR;
+#if 0
+ }
+#endif
+ }
+ (void) chmod(ofname, 0777);
+ if (unlink(ofname)) {
+ fprintf(stderr, "%s: ", progname);
+ perror(ofname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+ return OK;
+}
+
+
+/* ========================================================================
+ * Set the access and modification times from the given stat buffer.
+ */
+local void reset_times (name, statb)
+ char *name;
+ struct stat *statb;
+{
+ struct utimbuf timep;
+
+ /* Copy the time stamp */
+ timep.actime = statb->st_atime;
+ timep.modtime = statb->st_mtime;
+
+ /* Some systems (at least OS/2) do not support utime on directories */
+ if (utime(name, &timep) && !S_ISDIR(statb->st_mode)) {
+ WARN((stderr, "%s: ", progname));
+ if (!quiet) perror(ofname);
+ }
+}
+
+
+/* ========================================================================
+ * Copy modes, times, ownership from input file to output file.
+ * IN assertion: to_stdout is false.
+ */
+local void copy_stat(ifstat)
+ struct stat *ifstat;
+{
+ if (decompress && time_stamp != 0 && ifstat->st_mtime != time_stamp) {
+ ifstat->st_mtime = time_stamp;
+ if (verbose > 1) {
+ fprintf(stderr, "%s: time stamp restored\n", ofname);
+ }
+ }
+ reset_times(ofname, ifstat);
+
+ /* Copy the protection modes */
+ if (chmod(ofname, ifstat->st_mode & 07777)) {
+ WARN((stderr, "%s: ", progname));
+ if (!quiet) perror(ofname);
+ }
+
+ chown(ofname, ifstat->st_uid, ifstat->st_gid); /* Copy ownership */
+
+ remove_ofname = 0;
+ /* It's now safe to remove the input file: */
+ (void) chmod(ifname, 0777);
+ if (unlink(ifname)) {
+ WARN((stderr, "%s: ", progname));
+ if (!quiet) perror(ifname);
+ }
+}
+
+/* ========================================================================
+ * 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;
+ if (env != NULL) free(env), env = NULL;
+ if (args != NULL) free((char*)args), args = NULL;
+ FREE(inbuf);
+ FREE(outbuf);
+ FREE(d_buf);
+ FREE(window);
+ FREE(tab_prefix);
+ exit(exitcode);
+}
+
+/* ========================================================================
+ * Signal and error handler.
+ */
+void abort_gzip()
+{
+ if (remove_ofname) {
+ close(ofd);
+ unlink (ofname);
+ }
+ do_exit(ERROR);
+}