compress.c revision 87214 
1/*-
2 * Copyright (c) 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1992, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)compress.c	8.2 (Berkeley) 1/7/94";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/compress/compress.c 87214 2001-12-02 13:31:22Z markm $";
46#endif /* not lint */
47
48#include <sys/param.h>
49#include <sys/stat.h>
50#include <sys/time.h>
51
52#include <err.h>
53#include <errno.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58
59#ifdef __STDC__
60#include <stdarg.h>
61#else
62#include <varargs.h>
63#endif
64
65#include "zopen.h"
66
67void	compress __P((const char *, const char *, int));
68void	cwarn __P((const char *, ...)) __printflike(1, 2);
69void	cwarnx __P((const char *, ...)) __printflike(1, 2);
70void	decompress __P((const char *, const char *, int));
71int	permission __P((const char *));
72void	setfile __P((const char *, struct stat *));
73void	usage __P((int));
74
75int eval, force, verbose;
76
77int
78main(argc, argv)
79	int argc;
80	char *argv[];
81{
82	enum {COMPRESS, DECOMPRESS} style;
83	size_t len;
84	int bits, cat, ch;
85	char *p, newname[MAXPATHLEN];
86
87	cat = 0;
88	if ((p = rindex(argv[0], '/')) == NULL)
89		p = argv[0];
90	else
91		++p;
92	if (!strcmp(p, "uncompress"))
93		style = DECOMPRESS;
94	else if (!strcmp(p, "compress"))
95		style = COMPRESS;
96	else if (!strcmp(p, "zcat")) {
97		cat = 1;
98		style = DECOMPRESS;
99	} else
100		errx(1, "unknown program name");
101
102	bits = 0;
103	while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
104		switch(ch) {
105		case 'b':
106			bits = strtol(optarg, &p, 10);
107			if (*p)
108				errx(1, "illegal bit count -- %s", optarg);
109			break;
110		case 'c':
111			cat = 1;
112			break;
113		case 'd':		/* Backward compatible. */
114			style = DECOMPRESS;
115			break;
116		case 'f':
117			force = 1;
118			break;
119		case 'v':
120			verbose = 1;
121			break;
122		case '?':
123		default:
124			usage(style == COMPRESS);
125		}
126	argc -= optind;
127	argv += optind;
128
129	if (argc == 0) {
130		switch(style) {
131		case COMPRESS:
132			(void)compress("/dev/stdin", "/dev/stdout", bits);
133			break;
134		case DECOMPRESS:
135			(void)decompress("/dev/stdin", "/dev/stdout", bits);
136			break;
137		}
138		exit (eval);
139	}
140
141	if (cat == 1 && argc > 1)
142		errx(1, "the -c option permits only a single file argument");
143
144	for (; *argv; ++argv)
145		switch(style) {
146		case COMPRESS:
147			if (cat) {
148				compress(*argv, "/dev/stdout", bits);
149				break;
150			}
151			if ((p = rindex(*argv, '.')) != NULL &&
152			    !strcmp(p, ".Z")) {
153				cwarnx("%s: name already has trailing .Z",
154				    *argv);
155				break;
156			}
157			len = strlen(*argv);
158			if (len > sizeof(newname) - 3) {
159				cwarnx("%s: name too long", *argv);
160				break;
161			}
162			memmove(newname, *argv, len);
163			newname[len] = '.';
164			newname[len + 1] = 'Z';
165			newname[len + 2] = '\0';
166			compress(*argv, newname, bits);
167			break;
168		case DECOMPRESS:
169			len = strlen(*argv);
170			if ((p = rindex(*argv, '.')) == NULL ||
171			    strcmp(p, ".Z")) {
172				if (len > sizeof(newname) - 3) {
173					cwarnx("%s: name too long", *argv);
174					break;
175				}
176				memmove(newname, *argv, len);
177				newname[len] = '.';
178				newname[len + 1] = 'Z';
179				newname[len + 2] = '\0';
180				decompress(newname,
181				    cat ? "/dev/stdout" : *argv, bits);
182			} else {
183				if (len - 2 > sizeof(newname) - 1) {
184					cwarnx("%s: name too long", *argv);
185					break;
186				}
187				memmove(newname, *argv, len - 2);
188				newname[len - 2] = '\0';
189				decompress(*argv,
190				    cat ? "/dev/stdout" : newname, bits);
191			}
192			break;
193		}
194	exit (eval);
195}
196
197void
198compress(in, out, bits)
199	const char *in, *out;
200	int bits;
201{
202	size_t nr;
203	struct stat isb, sb;
204	FILE *ifp, *ofp;
205	int exists, isreg, oreg;
206	u_char buf[1024];
207
208	exists = !stat(out, &sb);
209	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
210		return;
211	isreg = oreg = !exists || S_ISREG(sb.st_mode);
212
213	ifp = ofp = NULL;
214	if ((ifp = fopen(in, "r")) == NULL) {
215		cwarn("%s", in);
216		return;
217	}
218	if (stat(in, &isb)) {		/* DON'T FSTAT! */
219		cwarn("%s", in);
220		goto err;
221	}
222	if (!S_ISREG(isb.st_mode))
223		isreg = 0;
224
225	if ((ofp = zopen(out, "w", bits)) == NULL) {
226		cwarn("%s", out);
227		goto err;
228	}
229	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
230		if (fwrite(buf, 1, nr, ofp) != nr) {
231			cwarn("%s", out);
232			goto err;
233		}
234
235	if (ferror(ifp) || fclose(ifp)) {
236		cwarn("%s", in);
237		goto err;
238	}
239	ifp = NULL;
240
241	if (fclose(ofp)) {
242		cwarn("%s", out);
243		goto err;
244	}
245	ofp = NULL;
246
247	if (isreg) {
248		if (stat(out, &sb)) {
249			cwarn("%s", out);
250			goto err;
251		}
252
253		if (!force && sb.st_size >= isb.st_size) {
254			if (verbose)
255		(void)printf("%s: file would grow; left unmodified\n", in);
256			if (unlink(out))
257				cwarn("%s", out);
258			goto err;
259		}
260
261		setfile(out, &isb);
262
263		if (unlink(in))
264			cwarn("%s", in);
265
266		if (verbose) {
267			(void)printf("%s: ", out);
268			if (isb.st_size > sb.st_size)
269				(void)printf("%.0f%% compression\n",
270				    ((float)sb.st_size / isb.st_size) * 100.0);
271			else
272				(void)printf("%.0f%% expansion\n",
273				    ((float)isb.st_size / sb.st_size) * 100.0);
274		}
275	}
276	return;
277
278err:	if (ofp) {
279		if (oreg)
280			(void)unlink(out);
281		(void)fclose(ofp);
282	}
283	if (ifp)
284		(void)fclose(ifp);
285}
286
287void
288decompress(in, out, bits)
289	const char *in, *out;
290	int bits;
291{
292	size_t nr;
293	struct stat sb;
294	FILE *ifp, *ofp;
295	int exists, isreg, oreg;
296	u_char buf[1024];
297
298	exists = !stat(out, &sb);
299	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
300		return;
301	isreg = oreg = !exists || S_ISREG(sb.st_mode);
302
303	ifp = ofp = NULL;
304	if ((ofp = fopen(out, "w")) == NULL) {
305		cwarn("%s", out);
306		return;
307	}
308
309	if ((ifp = zopen(in, "r", bits)) == NULL) {
310		cwarn("%s", in);
311		goto err;
312	}
313	if (stat(in, &sb)) {
314		cwarn("%s", in);
315		goto err;
316	}
317	if (!S_ISREG(sb.st_mode))
318		isreg = 0;
319
320	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
321		if (fwrite(buf, 1, nr, ofp) != nr) {
322			cwarn("%s", out);
323			goto err;
324		}
325
326	if (ferror(ifp) || fclose(ifp)) {
327		cwarn("%s", in);
328		goto err;
329	}
330	ifp = NULL;
331
332	if (fclose(ofp)) {
333		cwarn("%s", out);
334		goto err;
335	}
336
337	if (isreg) {
338		setfile(out, &sb);
339
340		if (unlink(in))
341			cwarn("%s", in);
342	}
343	return;
344
345err:	if (ofp) {
346		if (oreg)
347			(void)unlink(out);
348		(void)fclose(ofp);
349	}
350	if (ifp)
351		(void)fclose(ifp);
352}
353
354void
355setfile(name, fs)
356	const char *name;
357	struct stat *fs;
358{
359	static struct timeval tv[2];
360
361	fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
362
363	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
364	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
365	if (utimes(name, tv))
366		cwarn("utimes: %s", name);
367
368	/*
369	 * Changing the ownership probably won't succeed, unless we're root
370	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
371	 * the mode; current BSD behavior is to remove all setuid bits on
372	 * chown.  If chown fails, lose setuid/setgid bits.
373	 */
374	if (chown(name, fs->st_uid, fs->st_gid)) {
375		if (errno != EPERM)
376			cwarn("chown: %s", name);
377		fs->st_mode &= ~(S_ISUID|S_ISGID);
378	}
379	if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
380		cwarn("chmod: %s", name);
381
382	if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
383		cwarn("chflags: %s", name);
384}
385
386int
387permission(fname)
388	const char *fname;
389{
390	int ch, first;
391
392	if (!isatty(fileno(stderr)))
393		return (0);
394	(void)fprintf(stderr, "overwrite %s? ", fname);
395	first = ch = getchar();
396	while (ch != '\n' && ch != EOF)
397		ch = getchar();
398	return (first == 'y');
399}
400
401void
402usage(iscompress)
403	int iscompress;
404{
405	if (iscompress)
406		(void)fprintf(stderr,
407		    "usage: compress [-cfv] [-b bits] [file ...]\n");
408	else
409		(void)fprintf(stderr,
410		    "usage: uncompress [-c] [-b bits] [file ...]\n");
411	exit(1);
412}
413
414void
415#if __STDC__
416cwarnx(const char *fmt, ...)
417#else
418cwarnx(fmt, va_alist)
419	int eval;
420	const char *fmt;
421	va_dcl
422#endif
423{
424	va_list ap;
425#if __STDC__
426	va_start(ap, fmt);
427#else
428	va_start(ap);
429#endif
430	vwarnx(fmt, ap);
431	va_end(ap);
432	eval = 1;
433}
434
435void
436#if __STDC__
437cwarn(const char *fmt, ...)
438#else
439cwarn(fmt, va_alist)
440	int eval;
441	const char *fmt;
442	va_dcl
443#endif
444{
445	va_list ap;
446#if __STDC__
447	va_start(ap, fmt);
448#else
449	va_start(ap);
450#endif
451	vwarn(fmt, ap);
452	va_end(ap);
453	eval = 1;
454}
455