freebsd-skq/usr.bin/compress/compress.c
pfg 872b698bd4 General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

440 lines
9.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1992, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif
#if 0
#ifndef lint
static char sccsid[] = "@(#)compress.c 8.2 (Berkeley) 1/7/94";
#endif
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "zopen.h"
static void compress(const char *, const char *, int);
static void cwarn(const char *, ...) __printflike(1, 2);
static void cwarnx(const char *, ...) __printflike(1, 2);
static void decompress(const char *, const char *, int);
static int permission(const char *);
static void setfile(const char *, struct stat *);
static void usage(int);
static int eval, force, verbose;
int
main(int argc, char *argv[])
{
enum {COMPRESS, DECOMPRESS} style;
size_t len;
int bits, cat, ch;
char *p, newname[MAXPATHLEN];
cat = 0;
if ((p = strrchr(argv[0], '/')) == NULL)
p = argv[0];
else
++p;
if (!strcmp(p, "uncompress"))
style = DECOMPRESS;
else if (!strcmp(p, "compress"))
style = COMPRESS;
else if (!strcmp(p, "zcat")) {
cat = 1;
style = DECOMPRESS;
} else
errx(1, "unknown program name");
bits = 0;
while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
switch(ch) {
case 'b':
bits = strtol(optarg, &p, 10);
if (*p)
errx(1, "illegal bit count -- %s", optarg);
break;
case 'c':
cat = 1;
break;
case 'd': /* Backward compatible. */
style = DECOMPRESS;
break;
case 'f':
force = 1;
break;
case 'v':
verbose = 1;
break;
case '?':
default:
usage(style == COMPRESS);
}
argc -= optind;
argv += optind;
if (argc == 0) {
switch(style) {
case COMPRESS:
(void)compress("/dev/stdin", "/dev/stdout", bits);
break;
case DECOMPRESS:
(void)decompress("/dev/stdin", "/dev/stdout", bits);
break;
}
exit (eval);
}
if (cat == 1 && style == COMPRESS && argc > 1)
errx(1, "the -c option permits only a single file argument");
for (; *argv; ++argv)
switch(style) {
case COMPRESS:
if (strcmp(*argv, "-") == 0) {
compress("/dev/stdin", "/dev/stdout", bits);
break;
} else if (cat) {
compress(*argv, "/dev/stdout", bits);
break;
}
if ((p = strrchr(*argv, '.')) != NULL &&
!strcmp(p, ".Z")) {
cwarnx("%s: name already has trailing .Z",
*argv);
break;
}
len = strlen(*argv);
if (len > sizeof(newname) - 3) {
cwarnx("%s: name too long", *argv);
break;
}
memmove(newname, *argv, len);
newname[len] = '.';
newname[len + 1] = 'Z';
newname[len + 2] = '\0';
compress(*argv, newname, bits);
break;
case DECOMPRESS:
if (strcmp(*argv, "-") == 0) {
decompress("/dev/stdin", "/dev/stdout", bits);
break;
}
len = strlen(*argv);
if ((p = strrchr(*argv, '.')) == NULL ||
strcmp(p, ".Z")) {
if (len > sizeof(newname) - 3) {
cwarnx("%s: name too long", *argv);
break;
}
memmove(newname, *argv, len);
newname[len] = '.';
newname[len + 1] = 'Z';
newname[len + 2] = '\0';
decompress(newname,
cat ? "/dev/stdout" : *argv, bits);
} else {
if (len - 2 > sizeof(newname) - 1) {
cwarnx("%s: name too long", *argv);
break;
}
memmove(newname, *argv, len - 2);
newname[len - 2] = '\0';
decompress(*argv,
cat ? "/dev/stdout" : newname, bits);
}
break;
}
exit (eval);
}
static void
compress(const char *in, const char *out, int bits)
{
size_t nr;
struct stat isb, sb;
FILE *ifp, *ofp;
int exists, isreg, oreg;
u_char buf[1024];
exists = !stat(out, &sb);
if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
return;
isreg = oreg = !exists || S_ISREG(sb.st_mode);
ifp = ofp = NULL;
if ((ifp = fopen(in, "r")) == NULL) {
cwarn("%s", in);
return;
}
if (stat(in, &isb)) { /* DON'T FSTAT! */
cwarn("%s", in);
goto err;
}
if (!S_ISREG(isb.st_mode))
isreg = 0;
if ((ofp = zopen(out, "w", bits)) == NULL) {
cwarn("%s", out);
goto err;
}
while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
if (fwrite(buf, 1, nr, ofp) != nr) {
cwarn("%s", out);
goto err;
}
if (ferror(ifp) || fclose(ifp)) {
cwarn("%s", in);
goto err;
}
ifp = NULL;
if (fclose(ofp)) {
cwarn("%s", out);
goto err;
}
ofp = NULL;
if (isreg) {
if (stat(out, &sb)) {
cwarn("%s", out);
goto err;
}
if (!force && sb.st_size >= isb.st_size) {
if (verbose)
(void)fprintf(stderr, "%s: file would grow; left unmodified\n",
in);
eval = 2;
if (unlink(out))
cwarn("%s", out);
goto err;
}
setfile(out, &isb);
if (unlink(in))
cwarn("%s", in);
if (verbose) {
(void)fprintf(stderr, "%s: ", out);
if (isb.st_size > sb.st_size)
(void)fprintf(stderr, "%.0f%% compression\n",
((float)sb.st_size / isb.st_size) * 100.0);
else
(void)fprintf(stderr, "%.0f%% expansion\n",
((float)isb.st_size / sb.st_size) * 100.0);
}
}
return;
err: if (ofp) {
if (oreg)
(void)unlink(out);
(void)fclose(ofp);
}
if (ifp)
(void)fclose(ifp);
}
static void
decompress(const char *in, const char *out, int bits)
{
size_t nr;
struct stat sb;
FILE *ifp, *ofp;
int exists, isreg, oreg;
u_char buf[1024];
exists = !stat(out, &sb);
if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
return;
isreg = oreg = !exists || S_ISREG(sb.st_mode);
ifp = ofp = NULL;
if ((ifp = zopen(in, "r", bits)) == NULL) {
cwarn("%s", in);
return;
}
if (stat(in, &sb)) {
cwarn("%s", in);
goto err;
}
if (!S_ISREG(sb.st_mode))
isreg = 0;
/*
* Try to read the first few uncompressed bytes from the input file
* before blindly truncating the output file.
*/
if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) {
cwarn("%s", in);
(void)fclose(ifp);
return;
}
if ((ofp = fopen(out, "w")) == NULL ||
(nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) {
cwarn("%s", out);
(void)fclose(ifp);
return;
}
while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
if (fwrite(buf, 1, nr, ofp) != nr) {
cwarn("%s", out);
goto err;
}
if (ferror(ifp) || fclose(ifp)) {
cwarn("%s", in);
goto err;
}
ifp = NULL;
if (fclose(ofp)) {
cwarn("%s", out);
goto err;
}
if (isreg) {
setfile(out, &sb);
if (unlink(in))
cwarn("%s", in);
}
return;
err: if (ofp) {
if (oreg)
(void)unlink(out);
(void)fclose(ofp);
}
if (ifp)
(void)fclose(ifp);
}
static void
setfile(const char *name, struct stat *fs)
{
static struct timespec tspec[2];
fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
tspec[0] = fs->st_atim;
tspec[1] = fs->st_mtim;
if (utimensat(AT_FDCWD, name, tspec, 0))
cwarn("utimensat: %s", name);
/*
* Changing the ownership probably won't succeed, unless we're root
* or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting
* the mode; current BSD behavior is to remove all setuid bits on
* chown. If chown fails, lose setuid/setgid bits.
*/
if (chown(name, fs->st_uid, fs->st_gid)) {
if (errno != EPERM)
cwarn("chown: %s", name);
fs->st_mode &= ~(S_ISUID|S_ISGID);
}
if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
cwarn("chmod: %s", name);
if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
cwarn("chflags: %s", name);
}
static int
permission(const char *fname)
{
int ch, first;
if (!isatty(fileno(stderr)))
return (0);
(void)fprintf(stderr, "overwrite %s? ", fname);
first = ch = getchar();
while (ch != '\n' && ch != EOF)
ch = getchar();
return (first == 'y');
}
static void
usage(int iscompress)
{
if (iscompress)
(void)fprintf(stderr,
"usage: compress [-cfv] [-b bits] [file ...]\n");
else
(void)fprintf(stderr,
"usage: uncompress [-c] [-b bits] [file ...]\n");
exit(1);
}
static void
cwarnx(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vwarnx(fmt, ap);
va_end(ap);
eval = 1;
}
static void
cwarn(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vwarn(fmt, ap);
va_end(ap);
eval = 1;
}