1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1992, 1993\n\
35 The Regents of the University of California. All rights reserved.\n";
36 #endif
37
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)compress.c 8.2 (Berkeley) 1/7/94";
41 #endif
42 #endif
43
44 #include <sys/cdefs.h>
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/time.h>
48
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <stdarg.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57
58 #include "zopen.h"
59
60 static void compress(const char *, const char *, int);
61 static void cwarn(const char *, ...) __printflike(1, 2);
62 static void cwarnx(const char *, ...) __printflike(1, 2);
63 static void decompress(const char *, const char *, int);
64 static int permission(const char *);
65 static void setfile(const char *, struct stat *);
66 static void usage(int);
67
68 static int eval, force, verbose;
69
70 int
main(int argc,char * argv[])71 main(int argc, char *argv[])
72 {
73 enum {COMPRESS, DECOMPRESS} style;
74 size_t len;
75 int bits, cat, ch;
76 char *p, newname[MAXPATHLEN];
77
78 cat = 0;
79 if ((p = strrchr(argv[0], '/')) == NULL)
80 p = argv[0];
81 else
82 ++p;
83 if (!strcmp(p, "uncompress"))
84 style = DECOMPRESS;
85 else if (!strcmp(p, "compress"))
86 style = COMPRESS;
87 else if (!strcmp(p, "zcat")) {
88 cat = 1;
89 style = DECOMPRESS;
90 } else
91 errx(1, "unknown program name");
92
93 bits = 0;
94 while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
95 switch(ch) {
96 case 'b':
97 bits = strtol(optarg, &p, 10);
98 if (*p)
99 errx(1, "illegal bit count -- %s", optarg);
100 break;
101 case 'c':
102 cat = 1;
103 break;
104 case 'd': /* Backward compatible. */
105 style = DECOMPRESS;
106 break;
107 case 'f':
108 force = 1;
109 break;
110 case 'v':
111 verbose = 1;
112 break;
113 case '?':
114 default:
115 usage(style == COMPRESS);
116 }
117 argc -= optind;
118 argv += optind;
119
120 if (argc == 0) {
121 switch(style) {
122 case COMPRESS:
123 (void)compress("/dev/stdin", "/dev/stdout", bits);
124 break;
125 case DECOMPRESS:
126 (void)decompress("/dev/stdin", "/dev/stdout", bits);
127 break;
128 }
129 exit (eval);
130 }
131
132 if (cat == 1 && style == COMPRESS && argc > 1)
133 errx(1, "the -c option permits only a single file argument");
134
135 for (; *argv; ++argv)
136 switch(style) {
137 case COMPRESS:
138 if (strcmp(*argv, "-") == 0) {
139 compress("/dev/stdin", "/dev/stdout", bits);
140 break;
141 } else if (cat) {
142 compress(*argv, "/dev/stdout", bits);
143 break;
144 }
145 if ((p = strrchr(*argv, '.')) != NULL &&
146 !strcmp(p, ".Z")) {
147 cwarnx("%s: name already has trailing .Z",
148 *argv);
149 break;
150 }
151 len = strlen(*argv);
152 if (len > sizeof(newname) - 3) {
153 cwarnx("%s: name too long", *argv);
154 break;
155 }
156 memmove(newname, *argv, len);
157 newname[len] = '.';
158 newname[len + 1] = 'Z';
159 newname[len + 2] = '\0';
160 compress(*argv, newname, bits);
161 break;
162 case DECOMPRESS:
163 if (strcmp(*argv, "-") == 0) {
164 decompress("/dev/stdin", "/dev/stdout", bits);
165 break;
166 }
167 len = strlen(*argv);
168 if ((p = strrchr(*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 static void
compress(const char * in,const char * out,int bits)196 compress(const char *in, const char *out, int bits)
197 {
198 size_t nr;
199 struct stat isb, sb;
200 FILE *ifp, *ofp;
201 int exists, isreg, oreg;
202 u_char buf[1024];
203
204 exists = !stat(out, &sb);
205 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
206 return;
207 isreg = oreg = !exists || S_ISREG(sb.st_mode);
208
209 ifp = ofp = NULL;
210 if ((ifp = fopen(in, "r")) == NULL) {
211 cwarn("%s", in);
212 return;
213 }
214 if (stat(in, &isb)) { /* DON'T FSTAT! */
215 cwarn("%s", in);
216 goto err;
217 }
218 if (!S_ISREG(isb.st_mode))
219 isreg = 0;
220
221 if ((ofp = zopen(out, "w", bits)) == NULL) {
222 cwarn("%s", out);
223 goto err;
224 }
225 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
226 if (fwrite(buf, 1, nr, ofp) != nr) {
227 cwarn("%s", out);
228 goto err;
229 }
230
231 if (ferror(ifp) || fclose(ifp)) {
232 cwarn("%s", in);
233 goto err;
234 }
235 ifp = NULL;
236
237 if (fclose(ofp)) {
238 cwarn("%s", out);
239 goto err;
240 }
241 ofp = NULL;
242
243 if (isreg) {
244 if (stat(out, &sb)) {
245 cwarn("%s", out);
246 goto err;
247 }
248
249 if (!force && sb.st_size >= isb.st_size) {
250 if (verbose)
251 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
252 in);
253 eval = 2;
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)fprintf(stderr, "%s: ", out);
266 if (isb.st_size > sb.st_size)
267 (void)fprintf(stderr, "%.0f%% compression\n",
268 ((float)sb.st_size / isb.st_size) * 100.0);
269 else
270 (void)fprintf(stderr, "%.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 static void
decompress(const char * in,const char * out,int bits)286 decompress(const char *in, const char *out, int bits)
287 {
288 size_t nr;
289 struct stat sb;
290 FILE *ifp, *ofp;
291 int exists, isreg, oreg;
292 u_char buf[1024];
293
294 exists = !stat(out, &sb);
295 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
296 return;
297 isreg = oreg = !exists || S_ISREG(sb.st_mode);
298
299 ifp = ofp = NULL;
300 if ((ifp = zopen(in, "r", bits)) == NULL) {
301 cwarn("%s", in);
302 return;
303 }
304 if (stat(in, &sb)) {
305 cwarn("%s", in);
306 goto err;
307 }
308 if (!S_ISREG(sb.st_mode))
309 isreg = 0;
310
311 /*
312 * Try to read the first few uncompressed bytes from the input file
313 * before blindly truncating the output file.
314 */
315 if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) {
316 cwarn("%s", in);
317 (void)fclose(ifp);
318 return;
319 }
320 if ((ofp = fopen(out, "w")) == NULL ||
321 (nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) {
322 cwarn("%s", out);
323 if (ofp)
324 (void)fclose(ofp);
325 (void)fclose(ifp);
326 return;
327 }
328
329 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
330 if (fwrite(buf, 1, nr, ofp) != nr) {
331 cwarn("%s", out);
332 goto err;
333 }
334
335 if (ferror(ifp) || fclose(ifp)) {
336 cwarn("%s", in);
337 goto err;
338 }
339 ifp = NULL;
340
341 if (fclose(ofp)) {
342 cwarn("%s", out);
343 goto err;
344 }
345
346 if (isreg) {
347 setfile(out, &sb);
348
349 if (unlink(in))
350 cwarn("%s", in);
351 }
352 return;
353
354 err: if (ofp) {
355 if (oreg)
356 (void)unlink(out);
357 (void)fclose(ofp);
358 }
359 if (ifp)
360 (void)fclose(ifp);
361 }
362
363 static void
setfile(const char * name,struct stat * fs)364 setfile(const char *name, struct stat *fs)
365 {
366 static struct timespec tspec[2];
367
368 fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
369
370 tspec[0] = fs->st_atim;
371 tspec[1] = fs->st_mtim;
372 if (utimensat(AT_FDCWD, name, tspec, 0))
373 cwarn("utimensat: %s", name);
374
375 /*
376 * Changing the ownership probably won't succeed, unless we're root
377 * or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting
378 * the mode; current BSD behavior is to remove all setuid bits on
379 * chown. If chown fails, lose setuid/setgid bits.
380 */
381 if (chown(name, fs->st_uid, fs->st_gid)) {
382 if (errno != EPERM)
383 cwarn("chown: %s", name);
384 fs->st_mode &= ~(S_ISUID|S_ISGID);
385 }
386 if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
387 cwarn("chmod: %s", name);
388
389 if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
390 cwarn("chflags: %s", name);
391 }
392
393 static int
permission(const char * fname)394 permission(const char *fname)
395 {
396 int ch, first;
397
398 if (!isatty(fileno(stderr)))
399 return (0);
400 (void)fprintf(stderr, "overwrite %s? ", fname);
401 first = ch = getchar();
402 while (ch != '\n' && ch != EOF)
403 ch = getchar();
404 return (first == 'y');
405 }
406
407 static void
usage(int iscompress)408 usage(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
419 static void
cwarnx(const char * fmt,...)420 cwarnx(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
430 static void
cwarn(const char * fmt,...)431 cwarn(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