xref: /netbsd-src/usr.bin/compress/compress.c (revision 6929ad87a5c37179228b21785018bbb66fe06b56)
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
35 static 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 /*static char sccsid[] = "from: @(#)compress.c	8.2 (Berkeley) 1/7/94";*/
42 static char *rcsid = "$Id: compress.c,v 1.8 1994/12/24 16:27:18 cgd Exp $";
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/time.h>
47 #include <sys/stat.h>
48 
49 #include <err.h>
50 #include <errno.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <unistd.h>
55 
56 #ifdef __STDC__
57 #include <stdarg.h>
58 #else
59 #include <varargs.h>
60 #endif
61 
62 void	compress __P((char *, char *, int));
63 void	cwarn __P((const char *, ...));
64 void	cwarnx __P((const char *, ...));
65 void	decompress __P((char *, char *, int));
66 int	permission __P((char *));
67 void	setfile __P((char *, struct stat *));
68 void	usage __P((int));
69 
70 extern FILE *zopen __P((const char *fname, const char *mode, int bits));
71 
72 int eval, force, verbose;
73 
74 int
75 main(argc, argv)
76 	int argc;
77 	char *argv[];
78 {
79 	enum {COMPRESS, DECOMPRESS} style;
80 	size_t len;
81 	int bits, cat, ch;
82 	char *p, newname[MAXPATHLEN];
83 
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
93 		errx(1, "unknown program name");
94 
95 	bits = cat = 0;
96 	while ((ch = getopt(argc, argv, "b:cdfv")) != EOF)
97 		switch(ch) {
98 		case 'b':
99 			bits = strtol(optarg, &p, 10);
100 			if (*p)
101 				errx(1, "illegal bit count -- %s", optarg);
102 			break;
103 		case 'c':
104 			cat = 1;
105 			break;
106 		case 'd':		/* Backward compatible. */
107 			style = DECOMPRESS;
108 			break;
109 		case 'f':
110 			force = 1;
111 			break;
112 		case 'v':
113 			verbose = 1;
114 			break;
115 		case '?':
116 		default:
117 			usage(style == COMPRESS);
118 		}
119 	argc -= optind;
120 	argv += optind;
121 
122 	if (argc == 0) {
123 		switch(style) {
124 		case COMPRESS:
125 			(void)compress("/dev/stdin", "/dev/stdout", bits);
126 			break;
127 		case DECOMPRESS:
128 			(void)decompress("/dev/stdin", "/dev/stdout", bits);
129 			break;
130 		}
131 		exit (eval);
132 	}
133 
134 	if (cat == 1 && argc > 1)
135 		errx(1, "the -c option permits only a single file argument");
136 
137 	for (; *argv; ++argv)
138 		switch(style) {
139 		case COMPRESS:
140 			if (cat) {
141 				compress(*argv, "/dev/stdout", bits);
142 				break;
143 			}
144 			if ((p = rindex(*argv, '.')) != NULL &&
145 			    !strcmp(p, ".Z")) {
146 				cwarnx("%s: name already has trailing .Z",
147 				    *argv);
148 				break;
149 			}
150 			len = strlen(*argv);
151 			if (len > sizeof(newname) - 3) {
152 				cwarnx("%s: name too long", *argv);
153 				break;
154 			}
155 			memmove(newname, *argv, len);
156 			newname[len] = '.';
157 			newname[len + 1] = 'Z';
158 			newname[len + 2] = '\0';
159 			compress(*argv, newname, bits);
160 			break;
161 		case DECOMPRESS:
162 			len = strlen(*argv);
163 			if ((p = rindex(*argv, '.')) == NULL ||
164 			    strcmp(p, ".Z")) {
165 				if (len > sizeof(newname) - 3) {
166 					cwarnx("%s: name too long", *argv);
167 					break;
168 				}
169 				memmove(newname, *argv, len);
170 				newname[len] = '.';
171 				newname[len + 1] = 'Z';
172 				newname[len + 2] = '\0';
173 				decompress(newname,
174 				    cat ? "/dev/stdout" : *argv, bits);
175 			} else {
176 				if (len - 2 > sizeof(newname) - 1) {
177 					cwarnx("%s: name too long", *argv);
178 					break;
179 				}
180 				memmove(newname, *argv, len - 2);
181 				newname[len - 2] = '\0';
182 				decompress(*argv,
183 				    cat ? "/dev/stdout" : newname, bits);
184 			}
185 			break;
186 		}
187 	exit (eval);
188 }
189 
190 void
191 compress(in, out, bits)
192 	char *in, *out;
193 	int bits;
194 {
195 	register int nr;
196 	struct stat isb, sb;
197 	FILE *ifp, *ofp;
198 	int exists, isreg, oreg;
199 	u_char buf[1024];
200 
201 	exists = !stat(out, &sb);
202 	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
203 		return;
204 	isreg = oreg = !exists || S_ISREG(sb.st_mode);
205 
206 	ifp = ofp = NULL;
207 	if ((ifp = fopen(in, "r")) == NULL) {
208 		cwarn("%s", in);
209 		return;
210 	}
211 	if (stat(in, &isb)) {		/* DON'T FSTAT! */
212 		cwarn("%s", in);
213 		goto err;
214 	}
215 	if (!S_ISREG(isb.st_mode))
216 		isreg = 0;
217 
218 	if ((ofp = zopen(out, "w", bits)) == NULL) {
219 		cwarn("%s", out);
220 		goto err;
221 	}
222 	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
223 		if (fwrite(buf, 1, nr, ofp) != nr) {
224 			cwarn("%s", out);
225 			goto err;
226 		}
227 
228 	if (ferror(ifp) || fclose(ifp)) {
229 		cwarn("%s", in);
230 		goto err;
231 	}
232 	ifp = NULL;
233 
234 	if (fclose(ofp)) {
235 		cwarn("%s", out);
236 		goto err;
237 	}
238 	ofp = NULL;
239 
240 	if (isreg) {
241 		if (stat(out, &sb)) {
242 			cwarn("%s", out);
243 			goto err;
244 		}
245 
246 		if (!force && sb.st_size >= isb.st_size) {
247 			if (verbose)
248 		(void)printf("%s: file would grow; left unmodified\n", in);
249 			if (unlink(out))
250 				cwarn("%s", out);
251 			goto err;
252 		}
253 
254 		setfile(out, &isb);
255 
256 		if (unlink(in))
257 			cwarn("%s", in);
258 
259 		if (verbose) {
260 			(void)printf("%s: ", out);
261 			if (isb.st_size > sb.st_size)
262 				(void)printf("%.0f%% compression\n",
263 				    ((float)sb.st_size / isb.st_size) * 100.0);
264 			else
265 				(void)printf("%.0f%% expansion\n",
266 				    ((float)isb.st_size / sb.st_size) * 100.0);
267 		}
268 	}
269 	return;
270 
271 err:	if (ofp) {
272 		if (oreg)
273 			(void)unlink(out);
274 		(void)fclose(ofp);
275 	}
276 	if (ifp)
277 		(void)fclose(ifp);
278 }
279 
280 void
281 decompress(in, out, bits)
282 	char *in, *out;
283 	int bits;
284 {
285 	register int nr;
286 	struct stat sb;
287 	FILE *ifp, *ofp;
288 	int exists, isreg, oreg;
289 	u_char buf[1024];
290 
291 	exists = !stat(out, &sb);
292 	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
293 		return;
294 	isreg = oreg = !exists || S_ISREG(sb.st_mode);
295 
296 	ifp = ofp = NULL;
297 	if ((ofp = fopen(out, "w")) == NULL) {
298 		cwarn("%s", out);
299 		return;
300 	}
301 
302 	if ((ifp = zopen(in, "r", bits)) == NULL) {
303 		cwarn("%s", in);
304 		goto err;
305 	}
306 	if (stat(in, &sb)) {
307 		cwarn("%s", in);
308 		goto err;
309 	}
310 	if (!S_ISREG(sb.st_mode))
311 		isreg = 0;
312 
313 	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
314 		if (fwrite(buf, 1, nr, ofp) != nr) {
315 			cwarn("%s", out);
316 			goto err;
317 		}
318 
319 	if (ferror(ifp) || fclose(ifp)) {
320 		cwarn("%s", in);
321 		goto err;
322 	}
323 	ifp = NULL;
324 
325 	if (fclose(ofp)) {
326 		cwarn("%s", out);
327 		goto err;
328 	}
329 
330 	if (isreg) {
331 		setfile(out, &sb);
332 
333 		if (unlink(in))
334 			cwarn("%s", in);
335 	}
336 	return;
337 
338 err:	if (ofp) {
339 		if (oreg)
340 			(void)unlink(out);
341 		(void)fclose(ofp);
342 	}
343 	if (ifp)
344 		(void)fclose(ifp);
345 }
346 
347 void
348 setfile(name, fs)
349 	char *name;
350 	register struct stat *fs;
351 {
352 	static struct timeval tv[2];
353 
354 	fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
355 
356 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
357 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
358 	if (utimes(name, tv))
359 		cwarn("utimes: %s", name);
360 
361 	/*
362 	 * Changing the ownership probably won't succeed, unless we're root
363 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
364 	 * the mode; current BSD behavior is to remove all setuid bits on
365 	 * chown.  If chown fails, lose setuid/setgid bits.
366 	 */
367 	if (chown(name, fs->st_uid, fs->st_gid)) {
368 		if (errno != EPERM)
369 			cwarn("chown: %s", name);
370 		fs->st_mode &= ~(S_ISUID|S_ISGID);
371 	}
372 	if (chmod(name, fs->st_mode))
373 		cwarn("chown: %s", name);
374 
375 	if (chflags(name, fs->st_flags))
376 		cwarn("chflags: %s", name);
377 }
378 
379 int
380 permission(fname)
381 	char *fname;
382 {
383 	int ch, first;
384 
385 	if (!isatty(fileno(stderr)))
386 		return (0);
387 	(void)fprintf(stderr, "overwrite %s? ", fname);
388 	first = ch = getchar();
389 	while (ch != '\n' && ch != EOF)
390 		ch = getchar();
391 	return (first == 'y');
392 }
393 
394 void
395 usage(iscompress)
396 	int iscompress;
397 {
398 	if (iscompress)
399 		(void)fprintf(stderr,
400 		    "usage: compress [-cfv] [-b bits] [file ...]\n");
401 	else
402 		(void)fprintf(stderr,
403 		    "usage: uncompress [-c] [-b bits] [file ...]\n");
404 	exit(1);
405 }
406 
407 void
408 #if __STDC__
409 cwarnx(const char *fmt, ...)
410 #else
411 cwarnx(fmt, va_alist)
412 	int eval;
413 	const char *fmt;
414 	va_dcl
415 #endif
416 {
417 	va_list ap;
418 #if __STDC__
419 	va_start(ap, fmt);
420 #else
421 	va_start(ap);
422 #endif
423 	vwarnx(fmt, ap);
424 	va_end(ap);
425 	eval = 1;
426 }
427 
428 void
429 #if __STDC__
430 cwarn(const char *fmt, ...)
431 #else
432 cwarn(fmt, va_alist)
433 	int eval;
434 	const char *fmt;
435 	va_dcl
436 #endif
437 {
438 	va_list ap;
439 #if __STDC__
440 	va_start(ap, fmt);
441 #else
442 	va_start(ap);
443 #endif
444 	vwarn(fmt, ap);
445 	va_end(ap);
446 	eval = 1;
447 }
448