xref: /netbsd-src/usr.bin/compress/compress.c (revision 1f2744e6e4915c9da2a3f980279398c4cf7d5e6d)
1 /*	$NetBSD: compress.c,v 1.9 1995/03/26 09:44:38 glass Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1992, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)compress.c	8.2 (Berkeley) 1/7/94";
45 #else
46 static char rcsid[] = "$NetBSD: compress.c,v 1.9 1995/03/26 09:44:38 glass Exp $";
47 #endif
48 #endif /* not lint */
49 
50 #include <sys/param.h>
51 #include <sys/time.h>
52 #include <sys/stat.h>
53 
54 #include <err.h>
55 #include <errno.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 
61 #ifdef __STDC__
62 #include <stdarg.h>
63 #else
64 #include <varargs.h>
65 #endif
66 
67 void	compress __P((char *, char *, int));
68 void	cwarn __P((const char *, ...));
69 void	cwarnx __P((const char *, ...));
70 void	decompress __P((char *, char *, int));
71 int	permission __P((char *));
72 void	setfile __P((char *, struct stat *));
73 void	usage __P((int));
74 
75 extern FILE *zopen __P((const char *fname, const char *mode, int bits));
76 
77 int eval, force, verbose;
78 
79 int
80 main(argc, argv)
81 	int argc;
82 	char *argv[];
83 {
84 	enum {COMPRESS, DECOMPRESS} style;
85 	size_t len;
86 	int bits, cat, ch;
87 	char *p, newname[MAXPATHLEN];
88 
89 	if ((p = rindex(argv[0], '/')) == NULL)
90 		p = argv[0];
91 	else
92 		++p;
93 	if (!strcmp(p, "uncompress"))
94 		style = DECOMPRESS;
95 	else if (!strcmp(p, "compress"))
96 		style = COMPRESS;
97 	else
98 		errx(1, "unknown program name");
99 
100 	bits = cat = 0;
101 	while ((ch = getopt(argc, argv, "b:cdfv")) != EOF)
102 		switch(ch) {
103 		case 'b':
104 			bits = strtol(optarg, &p, 10);
105 			if (*p)
106 				errx(1, "illegal bit count -- %s", optarg);
107 			break;
108 		case 'c':
109 			cat = 1;
110 			break;
111 		case 'd':		/* Backward compatible. */
112 			style = DECOMPRESS;
113 			break;
114 		case 'f':
115 			force = 1;
116 			break;
117 		case 'v':
118 			verbose = 1;
119 			break;
120 		case '?':
121 		default:
122 			usage(style == COMPRESS);
123 		}
124 	argc -= optind;
125 	argv += optind;
126 
127 	if (argc == 0) {
128 		switch(style) {
129 		case COMPRESS:
130 			(void)compress("/dev/stdin", "/dev/stdout", bits);
131 			break;
132 		case DECOMPRESS:
133 			(void)decompress("/dev/stdin", "/dev/stdout", bits);
134 			break;
135 		}
136 		exit (eval);
137 	}
138 
139 	if (cat == 1 && argc > 1)
140 		errx(1, "the -c option permits only a single file argument");
141 
142 	for (; *argv; ++argv)
143 		switch(style) {
144 		case COMPRESS:
145 			if (cat) {
146 				compress(*argv, "/dev/stdout", bits);
147 				break;
148 			}
149 			if ((p = rindex(*argv, '.')) != NULL &&
150 			    !strcmp(p, ".Z")) {
151 				cwarnx("%s: name already has trailing .Z",
152 				    *argv);
153 				break;
154 			}
155 			len = strlen(*argv);
156 			if (len > sizeof(newname) - 3) {
157 				cwarnx("%s: name too long", *argv);
158 				break;
159 			}
160 			memmove(newname, *argv, len);
161 			newname[len] = '.';
162 			newname[len + 1] = 'Z';
163 			newname[len + 2] = '\0';
164 			compress(*argv, newname, bits);
165 			break;
166 		case DECOMPRESS:
167 			len = strlen(*argv);
168 			if ((p = rindex(*argv, '.')) == NULL ||
169 			    strcmp(p, ".Z")) {
170 				if (len > sizeof(newname) - 3) {
171 					cwarnx("%s: name too long", *argv);
172 					break;
173 				}
174 				memmove(newname, *argv, len);
175 				newname[len] = '.';
176 				newname[len + 1] = 'Z';
177 				newname[len + 2] = '\0';
178 				decompress(newname,
179 				    cat ? "/dev/stdout" : *argv, bits);
180 			} else {
181 				if (len - 2 > sizeof(newname) - 1) {
182 					cwarnx("%s: name too long", *argv);
183 					break;
184 				}
185 				memmove(newname, *argv, len - 2);
186 				newname[len - 2] = '\0';
187 				decompress(*argv,
188 				    cat ? "/dev/stdout" : newname, bits);
189 			}
190 			break;
191 		}
192 	exit (eval);
193 }
194 
195 void
196 compress(in, out, bits)
197 	char *in, *out;
198 	int bits;
199 {
200 	register int nr;
201 	struct stat isb, sb;
202 	FILE *ifp, *ofp;
203 	int exists, isreg, oreg;
204 	u_char buf[1024];
205 
206 	exists = !stat(out, &sb);
207 	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
208 		return;
209 	isreg = oreg = !exists || S_ISREG(sb.st_mode);
210 
211 	ifp = ofp = NULL;
212 	if ((ifp = fopen(in, "r")) == NULL) {
213 		cwarn("%s", in);
214 		return;
215 	}
216 	if (stat(in, &isb)) {		/* DON'T FSTAT! */
217 		cwarn("%s", in);
218 		goto err;
219 	}
220 	if (!S_ISREG(isb.st_mode))
221 		isreg = 0;
222 
223 	if ((ofp = zopen(out, "w", bits)) == NULL) {
224 		cwarn("%s", out);
225 		goto err;
226 	}
227 	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
228 		if (fwrite(buf, 1, nr, ofp) != nr) {
229 			cwarn("%s", out);
230 			goto err;
231 		}
232 
233 	if (ferror(ifp) || fclose(ifp)) {
234 		cwarn("%s", in);
235 		goto err;
236 	}
237 	ifp = NULL;
238 
239 	if (fclose(ofp)) {
240 		cwarn("%s", out);
241 		goto err;
242 	}
243 	ofp = NULL;
244 
245 	if (isreg) {
246 		if (stat(out, &sb)) {
247 			cwarn("%s", out);
248 			goto err;
249 		}
250 
251 		if (!force && sb.st_size >= isb.st_size) {
252 			if (verbose)
253 		(void)printf("%s: file would grow; left unmodified\n", in);
254 			if (unlink(out))
255 				cwarn("%s", out);
256 			goto err;
257 		}
258 
259 		setfile(out, &isb);
260 
261 		if (unlink(in))
262 			cwarn("%s", in);
263 
264 		if (verbose) {
265 			(void)printf("%s: ", out);
266 			if (isb.st_size > sb.st_size)
267 				(void)printf("%.0f%% compression\n",
268 				    ((float)sb.st_size / isb.st_size) * 100.0);
269 			else
270 				(void)printf("%.0f%% expansion\n",
271 				    ((float)isb.st_size / sb.st_size) * 100.0);
272 		}
273 	}
274 	return;
275 
276 err:	if (ofp) {
277 		if (oreg)
278 			(void)unlink(out);
279 		(void)fclose(ofp);
280 	}
281 	if (ifp)
282 		(void)fclose(ifp);
283 }
284 
285 void
286 decompress(in, out, bits)
287 	char *in, *out;
288 	int bits;
289 {
290 	register int nr;
291 	struct stat sb;
292 	FILE *ifp, *ofp;
293 	int exists, isreg, oreg;
294 	u_char buf[1024];
295 
296 	exists = !stat(out, &sb);
297 	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
298 		return;
299 	isreg = oreg = !exists || S_ISREG(sb.st_mode);
300 
301 	ifp = ofp = NULL;
302 	if ((ofp = fopen(out, "w")) == NULL) {
303 		cwarn("%s", out);
304 		return;
305 	}
306 
307 	if ((ifp = zopen(in, "r", bits)) == NULL) {
308 		cwarn("%s", in);
309 		goto err;
310 	}
311 	if (stat(in, &sb)) {
312 		cwarn("%s", in);
313 		goto err;
314 	}
315 	if (!S_ISREG(sb.st_mode))
316 		isreg = 0;
317 
318 	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
319 		if (fwrite(buf, 1, nr, ofp) != nr) {
320 			cwarn("%s", out);
321 			goto err;
322 		}
323 
324 	if (ferror(ifp) || fclose(ifp)) {
325 		cwarn("%s", in);
326 		goto err;
327 	}
328 	ifp = NULL;
329 
330 	if (fclose(ofp)) {
331 		cwarn("%s", out);
332 		goto err;
333 	}
334 
335 	if (isreg) {
336 		setfile(out, &sb);
337 
338 		if (unlink(in))
339 			cwarn("%s", in);
340 	}
341 	return;
342 
343 err:	if (ofp) {
344 		if (oreg)
345 			(void)unlink(out);
346 		(void)fclose(ofp);
347 	}
348 	if (ifp)
349 		(void)fclose(ifp);
350 }
351 
352 void
353 setfile(name, fs)
354 	char *name;
355 	register struct stat *fs;
356 {
357 	static struct timeval tv[2];
358 
359 	fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
360 
361 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
362 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
363 	if (utimes(name, tv))
364 		cwarn("utimes: %s", name);
365 
366 	/*
367 	 * Changing the ownership probably won't succeed, unless we're root
368 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
369 	 * the mode; current BSD behavior is to remove all setuid bits on
370 	 * chown.  If chown fails, lose setuid/setgid bits.
371 	 */
372 	if (chown(name, fs->st_uid, fs->st_gid)) {
373 		if (errno != EPERM)
374 			cwarn("chown: %s", name);
375 		fs->st_mode &= ~(S_ISUID|S_ISGID);
376 	}
377 	if (chmod(name, fs->st_mode))
378 		cwarn("chown: %s", name);
379 
380 	if (chflags(name, fs->st_flags))
381 		cwarn("chflags: %s", name);
382 }
383 
384 int
385 permission(fname)
386 	char *fname;
387 {
388 	int ch, first;
389 
390 	if (!isatty(fileno(stderr)))
391 		return (0);
392 	(void)fprintf(stderr, "overwrite %s? ", fname);
393 	first = ch = getchar();
394 	while (ch != '\n' && ch != EOF)
395 		ch = getchar();
396 	return (first == 'y');
397 }
398 
399 void
400 usage(iscompress)
401 	int iscompress;
402 {
403 	if (iscompress)
404 		(void)fprintf(stderr,
405 		    "usage: compress [-cfv] [-b bits] [file ...]\n");
406 	else
407 		(void)fprintf(stderr,
408 		    "usage: uncompress [-c] [-b bits] [file ...]\n");
409 	exit(1);
410 }
411 
412 void
413 #if __STDC__
414 cwarnx(const char *fmt, ...)
415 #else
416 cwarnx(fmt, va_alist)
417 	int eval;
418 	const char *fmt;
419 	va_dcl
420 #endif
421 {
422 	va_list ap;
423 #if __STDC__
424 	va_start(ap, fmt);
425 #else
426 	va_start(ap);
427 #endif
428 	vwarnx(fmt, ap);
429 	va_end(ap);
430 	eval = 1;
431 }
432 
433 void
434 #if __STDC__
435 cwarn(const char *fmt, ...)
436 #else
437 cwarn(fmt, va_alist)
438 	int eval;
439 	const char *fmt;
440 	va_dcl
441 #endif
442 {
443 	va_list ap;
444 #if __STDC__
445 	va_start(ap, fmt);
446 #else
447 	va_start(ap);
448 #endif
449 	vwarn(fmt, ap);
450 	va_end(ap);
451 	eval = 1;
452 }
453