xref: /dragonfly/usr.bin/patch/util.c (revision 36a3d1d6) 
1 /*
2  * $OpenBSD: util.c,v 1.32 2006/03/11 19:41:30 otto Exp $
3  * $DragonFly: src/usr.bin/patch/util.c,v 1.9 2007/09/29 23:11:10 swildner Exp $
4  */
5 
6 /*
7  * patch - a program to apply diffs to original files
8  *
9  * Copyright 1986, Larry Wall
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following condition is met:
13  * 1. Redistributions of source code must retain the above copyright notice,
14  * this condition and the following disclaimer.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
29  * behaviour
30  */
31 
32 #include <sys/param.h>
33 #include <sys/stat.h>
34 
35 #include <ctype.h>
36 #include <errno.h>
37 #include <fcntl.h>
38 #include <libgen.h>
39 #include <paths.h>
40 #include <signal.h>
41 #include <stdarg.h>
42 #include <stdlib.h>
43 #include <stdio.h>
44 #include <string.h>
45 #include <unistd.h>
46 
47 #include "common.h"
48 #include "util.h"
49 #include "backupfile.h"
50 #include "pathnames.h"
51 
52 /* Rename a file, copying it if necessary. */
53 
54 int
55 move_file(const char *from, const char *to)
56 {
57 	int	fromfd;
58 	ssize_t	i;
59 
60 	/* to stdout? */
61 
62 	if (strEQ(to, "-")) {
63 #ifdef DEBUGGING
64 		if (debug & 4)
65 			say("Moving %s to stdout.\n", from);
66 #endif
67 		fromfd = open(from, O_RDONLY);
68 		if (fromfd < 0)
69 			pfatal("internal error, can't reopen %s", from);
70 		while ((i = read(fromfd, buf, buf_len)) > 0)
71 			if (write(STDOUT_FILENO, buf, i) != i)
72 				pfatal("write failed");
73 		close(fromfd);
74 		return 0;
75 	}
76 	if (backup_file(to) < 0) {
77 		say("Can't backup %s, output is in %s: %s\n", to, from,
78 		    strerror(errno));
79 		return -1;
80 	}
81 #ifdef DEBUGGING
82 	if (debug & 4)
83 		say("Moving %s to %s.\n", from, to);
84 #endif
85 	if (rename(from, to) < 0) {
86 		if (errno != EXDEV || copy_file(from, to) < 0) {
87 			say("Can't create %s, output is in %s: %s\n",
88 			    to, from, strerror(errno));
89 			return -1;
90 		}
91 	}
92 	return 0;
93 }
94 
95 /* Backup the original file.  */
96 
97 int
98 backup_file(const char *orig)
99 {
100 	struct stat	filestat;
101 	char		bakname[MAXPATHLEN], *s, *simplename;
102 	dev_t		orig_device;
103 	ino_t		orig_inode;
104 
105 	if (backup_type == none || stat(orig, &filestat) != 0)
106 		return 0;			/* nothing to do */
107 	/*
108 	 * If the user used zero prefixes or suffixes, then
109 	 * he doesn't want backups.  Yet we have to remove
110 	 * orig to break possible hardlinks.
111 	 */
112 	if ((origprae && *origprae == 0) || *simple_backup_suffix == 0) {
113 		unlink(orig);
114 		return 0;
115 	}
116 	orig_device = filestat.st_dev;
117 	orig_inode = filestat.st_ino;
118 
119 	if (origprae) {
120 		if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
121 		    strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
122 			fatal("filename %s too long for buffer\n", origprae);
123 	} else {
124 		if ((s = find_backup_file_name(orig)) == NULL)
125 			fatal("out of memory\n");
126 		if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
127 			fatal("filename %s too long for buffer\n", s);
128 		free(s);
129 	}
130 
131 	if ((simplename = strrchr(bakname, '/')) != NULL)
132 		simplename = simplename + 1;
133 	else
134 		simplename = bakname;
135 
136 	/*
137 	 * Find a backup name that is not the same file. Change the
138 	 * first lowercase char into uppercase; if that isn't
139 	 * sufficient, chop off the first char and try again.
140 	 */
141 	while (stat(bakname, &filestat) == 0 &&
142 	    orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
143 		/* Skip initial non-lowercase chars.  */
144 		for (s = simplename; *s && !islower((unsigned char)*s); s++)
145 			;
146 		if (*s)
147 			*s = toupper((unsigned char)*s);
148 		else
149 			memmove(simplename, simplename + 1,
150 			    strlen(simplename + 1) + 1);
151 	}
152 #ifdef DEBUGGING
153 	if (debug & 4)
154 		say("Moving %s to %s.\n", orig, bakname);
155 #endif
156 	if (rename(orig, bakname) < 0) {
157 		if (errno != EXDEV || copy_file(orig, bakname) < 0)
158 			return -1;
159 	}
160 	return 0;
161 }
162 
163 /*
164  * Copy a file.
165  */
166 int
167 copy_file(const char *from, const char *to)
168 {
169 	int	tofd, fromfd;
170 	ssize_t	i;
171 
172 	tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
173 	if (tofd < 0)
174 		return -1;
175 	fromfd = open(from, O_RDONLY, 0);
176 	if (fromfd < 0)
177 		pfatal("internal error, can't reopen %s", from);
178 	while ((i = read(fromfd, buf, buf_len)) > 0)
179 		if (write(tofd, buf, i) != i)
180 			pfatal("write to %s failed", to);
181 	close(fromfd);
182 	close(tofd);
183 	return 0;
184 }
185 
186 /*
187  * Allocate a unique area for a string.
188  */
189 char *
190 savestr(const char *s)
191 {
192 	char	*rv;
193 
194 	if (!s)
195 		s = "Oops";
196 	rv = strdup(s);
197 	if (rv == NULL) {
198 		if (using_plan_a)
199 			out_of_mem = true;
200 		else
201 			fatal("out of memory\n");
202 	}
203 	return rv;
204 }
205 
206 /*
207  * Vanilla terminal output (buffered).
208  */
209 void
210 say(const char *fmt, ...)
211 {
212 	va_list	ap;
213 
214 	va_start(ap, fmt);
215 	vfprintf(stderr, fmt, ap);
216 	va_end(ap);
217 	fflush(stderr);
218 }
219 
220 /*
221  * Terminal output, pun intended.
222  */
223 void
224 fatal(const char *fmt, ...)
225 {
226 	va_list	ap;
227 
228 	va_start(ap, fmt);
229 	fprintf(stderr, "patch: **** ");
230 	vfprintf(stderr, fmt, ap);
231 	va_end(ap);
232 	my_exit(2);
233 }
234 
235 /*
236  * Say something from patch, something from the system, then silence . . .
237  */
238 void
239 pfatal(const char *fmt, ...)
240 {
241 	va_list	ap;
242 	int	errnum = errno;
243 
244 	fprintf(stderr, "patch: **** ");
245 	va_start(ap, fmt);
246 	vfprintf(stderr, fmt, ap);
247 	va_end(ap);
248 	fprintf(stderr, ": %s\n", strerror(errnum));
249 	my_exit(2);
250 }
251 
252 /*
253  * Get a response from the user via /dev/tty
254  */
255 void
256 ask(const char *fmt, ...)
257 {
258 	va_list	ap;
259 	ssize_t	nr = 0;
260 	static	int ttyfd = -1;
261 
262 	va_start(ap, fmt);
263 	vfprintf(stdout, fmt, ap);
264 	va_end(ap);
265 	fflush(stdout);
266 	if (ttyfd < 0)
267 		ttyfd = open(_PATH_TTY, O_RDONLY);
268 	if (ttyfd >= 0) {
269 		if ((nr = read(ttyfd, buf, buf_len)) > 0 &&
270 		    buf[nr - 1] == '\n')
271 			buf[nr - 1] = '\0';
272 	}
273 	if (ttyfd < 0 || nr <= 0) {
274 		/* no tty or error reading, pretend user entered 'return' */
275 		putchar('\n');
276 		buf[0] = '\0';
277 	}
278 }
279 
280 /*
281  * How to handle certain events when not in a critical region.
282  */
283 void
284 set_signals(int reset)
285 {
286 	static sig_t	hupval, intval;
287 
288 	if (!reset) {
289 		hupval = signal(SIGHUP, SIG_IGN);
290 		if (hupval != SIG_IGN)
291 			hupval = my_exit;
292 		intval = signal(SIGINT, SIG_IGN);
293 		if (intval != SIG_IGN)
294 			intval = my_exit;
295 	}
296 	signal(SIGHUP, hupval);
297 	signal(SIGINT, intval);
298 }
299 
300 /*
301  * How to handle certain events when in a critical region.
302  */
303 void
304 ignore_signals(void)
305 {
306 	signal(SIGHUP, SIG_IGN);
307 	signal(SIGINT, SIG_IGN);
308 }
309 
310 /*
311  * Make sure we'll have the directories to create a file. If `striplast' is
312  * true, ignore the last element of `filename'.
313  */
314 
315 void
316 makedirs(const char *filename, bool striplast)
317 {
318 	char	*tmpbuf;
319 
320 	if ((tmpbuf = strdup(filename)) == NULL)
321 		fatal("out of memory\n");
322 
323 	if (striplast) {
324 		char	*s = strrchr(tmpbuf, '/');
325 		if (s == NULL) {
326 			free(tmpbuf);
327 			return;	/* nothing to be done */
328 		}
329 		*s = '\0';
330 	}
331 	if (mkpath(tmpbuf) != 0)
332 		pfatal("creation of %s failed", tmpbuf);
333 	free(tmpbuf);
334 }
335 
336 /*
337  * Make filenames more reasonable.
338  */
339 char *
340 fetchname(const char *at, bool *exists, int strip_leading)
341 {
342 	char		*fullname, *name, *t;
343 	int		sleading, tab;
344 	struct stat	filestat;
345 
346 	if (at == NULL || *at == '\0')
347 		return NULL;
348 	while (isspace((unsigned char)*at))
349 		at++;
350 #ifdef DEBUGGING
351 	if (debug & 128)
352 		say("fetchname %s %d\n", at, strip_leading);
353 #endif
354 	/* So files can be created by diffing against /dev/null.  */
355 	if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
356 		return NULL;
357 	name = fullname = t = savestr(at);
358 
359 	tab = strchr(t, '\t') != NULL;
360 	/* Strip off up to `strip_leading' path components and NUL terminate. */
361 	for (sleading = strip_leading; *t != '\0' && ((tab && *t != '\t') ||
362 	    !isspace((unsigned char)*t)); t++) {
363 		if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
364 			if (--sleading >= 0)
365 				name = t + 1;
366 	}
367 	*t = '\0';
368 
369 	/*
370 	 * If no -p option was given (957 is the default value!), we were
371 	 * given a relative pathname, and the leading directories that we
372 	 * just stripped off all exist, put them back on.
373 	 */
374 	if (strip_leading == 957 && name != fullname && *fullname != '/') {
375 		name[-1] = '\0';
376 		if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
377 			name[-1] = '/';
378 			name = fullname;
379 		}
380 	}
381 	name = savestr(name);
382 	free(fullname);
383 
384 	*exists = stat(name, &filestat) == 0;
385 	return name;
386 }
387 
388 /*
389  * Takes the name returned by fetchname and looks in RCS/SCCS directories
390  * for a checked in version.
391  */
392 char *
393 checked_in(char *file)
394 {
395 	char		*filebase, *filedir, tmpbuf[MAXPATHLEN];
396 	struct stat	filestat;
397 
398 	filebase = basename(file);
399 	filedir = dirname(file);
400 
401 #define try(f, a1, a2, a3) \
402 (snprintf(tmpbuf, sizeof tmpbuf, f, a1, a2, a3), stat(tmpbuf, &filestat) == 0)
403 
404 	if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
405 	    try("%s/RCS/%s%s", filedir, filebase, "") ||
406 	    try("%s/%s%s", filedir, filebase, RCSSUFFIX) ||
407 	    try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
408 	    try("%s/%s%s", filedir, SCCSPREFIX, filebase))
409 		return file;
410 
411 	return NULL;
412 }
413 
414 void
415 version(void)
416 {
417 	fprintf(stderr, "Patch version 2.0-12u8-OpenBSD\n");
418 	my_exit(EXIT_SUCCESS);
419 }
420 
421 /*
422  * Exit with cleanup.
423  */
424 void
425 my_exit(int status)
426 {
427 	unlink(TMPINNAME);
428 	if (!toutkeep)
429 		unlink(TMPOUTNAME);
430 	if (!trejkeep)
431 		unlink(TMPREJNAME);
432 	unlink(TMPPATNAME);
433 	exit(status);
434 }
435