compress.c revision 96772 
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
39
40#if 0
41#ifndef lint
42static char sccsid[] = "@(#)compress.c	8.2 (Berkeley) 1/7/94";
43#endif
44#endif
45
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD: head/usr.bin/compress/compress.c 96772 2002-05-17 01:42:43Z tjr $");
48
49#include <sys/param.h>
50#include <sys/stat.h>
51#include <sys/time.h>
52
53#include <err.h>
54#include <errno.h>
55#include <stdarg.h>
56#include <stdio.h>
57#include <stdlib.h>
58#include <string.h>
59#include <unistd.h>
60
61#include "zopen.h"
62
63void	compress(const char *, const char *, int);
64void	cwarn(const char *, ...) __printflike(1, 2);
65void	cwarnx(const char *, ...) __printflike(1, 2);
66void	decompress(const char *, const char *, int);
67int	permission(const char *);
68void	setfile(const char *, struct stat *);
69void	usage(int);
70
71int eval, force, verbose;
72
73int
74main(argc, argv)
75	int argc;
76	char *argv[];
77{
78	enum {COMPRESS, DECOMPRESS} style;
79	size_t len;
80	int bits, cat, ch;
81	char *p, newname[MAXPATHLEN];
82
83	cat = 0;
84	if ((p = rindex(argv[0], '/')) == NULL)
85		p = argv[0];
86	else
87		++p;
88	if (!strcmp(p, "uncompress"))
89		style = DECOMPRESS;
90	else if (!strcmp(p, "compress"))
91		style = COMPRESS;
92	else if (!strcmp(p, "zcat")) {
93		cat = 1;
94		style = DECOMPRESS;
95	} else
96		errx(1, "unknown program name");
97
98	bits = 0;
99	while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
100		switch(ch) {
101		case 'b':
102			bits = strtol(optarg, &p, 10);
103			if (*p)
104				errx(1, "illegal bit count -- %s", optarg);
105			break;
106		case 'c':
107			cat = 1;
108			break;
109		case 'd':		/* Backward compatible. */
110			style = DECOMPRESS;
111			break;
112		case 'f':
113			force = 1;
114			break;
115		case 'v':
116			verbose = 1;
117			break;
118		case '?':
119		default:
120			usage(style == COMPRESS);
121		}
122	argc -= optind;
123	argv += optind;
124
125	if (argc == 0) {
126		switch(style) {
127		case COMPRESS:
128			(void)compress("/dev/stdin", "/dev/stdout", bits);
129			break;
130		case DECOMPRESS:
131			(void)decompress("/dev/stdin", "/dev/stdout", bits);
132			break;
133		}
134		exit (eval);
135	}
136
137	if (cat == 1 && argc > 1)
138		errx(1, "the -c option permits only a single file argument");
139
140	for (; *argv; ++argv)
141		switch(style) {
142		case COMPRESS:
143			if (strcmp(*argv, "-") == 0) {
144				compress("/dev/stdin", "/dev/stdout", bits);
145				break;
146			} else if (cat) {
147				compress(*argv, "/dev/stdout", bits);
148				break;
149			}
150			if ((p = rindex(*argv, '.')) != NULL &&
151			    !strcmp(p, ".Z")) {
152				cwarnx("%s: name already has trailing .Z",
153				    *argv);
154				break;
155			}
156			len = strlen(*argv);
157			if (len > sizeof(newname) - 3) {
158				cwarnx("%s: name too long", *argv);
159				break;
160			}
161			memmove(newname, *argv, len);
162			newname[len] = '.';
163			newname[len + 1] = 'Z';
164			newname[len + 2] = '\0';
165			compress(*argv, newname, bits);
166			break;
167		case DECOMPRESS:
168			if (strcmp(*argv, "-") == 0) {
169				decompress("/dev/stdin", "/dev/stdout", bits);
170				break;
171			}
172			len = strlen(*argv);
173			if ((p = rindex(*argv, '.')) == NULL ||
174			    strcmp(p, ".Z")) {
175				if (len > sizeof(newname) - 3) {
176					cwarnx("%s: name too long", *argv);
177					break;
178				}
179				memmove(newname, *argv, len);
180				newname[len] = '.';
181				newname[len + 1] = 'Z';
182				newname[len + 2] = '\0';
183				decompress(newname,
184				    cat ? "/dev/stdout" : *argv, bits);
185			} else {
186				if (len - 2 > sizeof(newname) - 1) {
187					cwarnx("%s: name too long", *argv);
188					break;
189				}
190				memmove(newname, *argv, len - 2);
191				newname[len - 2] = '\0';
192				decompress(*argv,
193				    cat ? "/dev/stdout" : newname, bits);
194			}
195			break;
196		}
197	exit (eval);
198}
199
200void
201compress(in, out, bits)
202	const char *in, *out;
203	int bits;
204{
205	size_t nr;
206	struct stat isb, sb;
207	FILE *ifp, *ofp;
208	int exists, isreg, oreg;
209	u_char buf[1024];
210
211	exists = !stat(out, &sb);
212	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
213		return;
214	isreg = oreg = !exists || S_ISREG(sb.st_mode);
215
216	ifp = ofp = NULL;
217	if ((ifp = fopen(in, "r")) == NULL) {
218		cwarn("%s", in);
219		return;
220	}
221	if (stat(in, &isb)) {		/* DON'T FSTAT! */
222		cwarn("%s", in);
223		goto err;
224	}
225	if (!S_ISREG(isb.st_mode))
226		isreg = 0;
227
228	if ((ofp = zopen(out, "w", bits)) == NULL) {
229		cwarn("%s", out);
230		goto err;
231	}
232	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
233		if (fwrite(buf, 1, nr, ofp) != nr) {
234			cwarn("%s", out);
235			goto err;
236		}
237
238	if (ferror(ifp) || fclose(ifp)) {
239		cwarn("%s", in);
240		goto err;
241	}
242	ifp = NULL;
243
244	if (fclose(ofp)) {
245		cwarn("%s", out);
246		goto err;
247	}
248	ofp = NULL;
249
250	if (isreg) {
251		if (stat(out, &sb)) {
252			cwarn("%s", out);
253			goto err;
254		}
255
256		if (!force && sb.st_size >= isb.st_size) {
257			if (verbose)
258		(void)fprintf(stderr, "%s: file would grow; left unmodified\n",
259		    in);
260			eval = 2;
261			if (unlink(out))
262				cwarn("%s", out);
263			goto err;
264		}
265
266		setfile(out, &isb);
267
268		if (unlink(in))
269			cwarn("%s", in);
270
271		if (verbose) {
272			(void)fprintf(stderr, "%s: ", out);
273			if (isb.st_size > sb.st_size)
274				(void)fprintf(stderr, "%.0f%% compression\n",
275				    ((float)sb.st_size / isb.st_size) * 100.0);
276			else
277				(void)fprintf(stderr, "%.0f%% expansion\n",
278				    ((float)isb.st_size / sb.st_size) * 100.0);
279		}
280	}
281	return;
282
283err:	if (ofp) {
284		if (oreg)
285			(void)unlink(out);
286		(void)fclose(ofp);
287	}
288	if (ifp)
289		(void)fclose(ifp);
290}
291
292void
293decompress(in, out, bits)
294	const char *in, *out;
295	int bits;
296{
297	size_t nr;
298	struct stat sb;
299	FILE *ifp, *ofp;
300	int exists, isreg, oreg;
301	u_char buf[1024];
302
303	exists = !stat(out, &sb);
304	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
305		return;
306	isreg = oreg = !exists || S_ISREG(sb.st_mode);
307
308	ifp = ofp = NULL;
309	if ((ofp = fopen(out, "w")) == NULL) {
310		cwarn("%s", out);
311		return;
312	}
313
314	if ((ifp = zopen(in, "r", bits)) == NULL) {
315		cwarn("%s", in);
316		goto err;
317	}
318	if (stat(in, &sb)) {
319		cwarn("%s", in);
320		goto err;
321	}
322	if (!S_ISREG(sb.st_mode))
323		isreg = 0;
324
325	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
326		if (fwrite(buf, 1, nr, ofp) != nr) {
327			cwarn("%s", out);
328			goto err;
329		}
330
331	if (ferror(ifp) || fclose(ifp)) {
332		cwarn("%s", in);
333		goto err;
334	}
335	ifp = NULL;
336
337	if (fclose(ofp)) {
338		cwarn("%s", out);
339		goto err;
340	}
341
342	if (isreg) {
343		setfile(out, &sb);
344
345		if (unlink(in))
346			cwarn("%s", in);
347	}
348	return;
349
350err:	if (ofp) {
351		if (oreg)
352			(void)unlink(out);
353		(void)fclose(ofp);
354	}
355	if (ifp)
356		(void)fclose(ifp);
357}
358
359void
360setfile(name, fs)
361	const char *name;
362	struct stat *fs;
363{
364	static struct timeval tv[2];
365
366	fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
367
368	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
369	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
370	if (utimes(name, tv))
371		cwarn("utimes: %s", name);
372
373	/*
374	 * Changing the ownership probably won't succeed, unless we're root
375	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
376	 * the mode; current BSD behavior is to remove all setuid bits on
377	 * chown.  If chown fails, lose setuid/setgid bits.
378	 */
379	if (chown(name, fs->st_uid, fs->st_gid)) {
380		if (errno != EPERM)
381			cwarn("chown: %s", name);
382		fs->st_mode &= ~(S_ISUID|S_ISGID);
383	}
384	if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
385		cwarn("chmod: %s", name);
386
387	if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
388		cwarn("chflags: %s", name);
389}
390
391int
392permission(fname)
393	const char *fname;
394{
395	int ch, first;
396
397	if (!isatty(fileno(stderr)))
398		return (0);
399	(void)fprintf(stderr, "overwrite %s? ", fname);
400	first = ch = getchar();
401	while (ch != '\n' && ch != EOF)
402		ch = getchar();
403	return (first == 'y');
404}
405
406void
407usage(iscompress)
408	int iscompress;
409{
410	if (iscompress)
411		(void)fprintf(stderr,
412		    "usage: compress [-cfv] [-b bits] [file ...]\n");
413	else
414		(void)fprintf(stderr,
415		    "usage: uncompress [-c] [-b bits] [file ...]\n");
416	exit(1);
417}
418
419void
420cwarnx(const char *fmt, ...)
421{
422	va_list ap;
423
424	va_start(ap, fmt);
425	vwarnx(fmt, ap);
426	va_end(ap);
427	eval = 1;
428}
429
430void
431cwarn(const char *fmt, ...)
432{
433	va_list ap;
434
435	va_start(ap, fmt);
436	vwarn(fmt, ap);
437	va_end(ap);
438	eval = 1;
439}
440