1/*-
2 * Copyright 1986, Larry Wall
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following condition is met:
6 * 1. Redistributions of source code must retain the above copyright notice,
7 * this condition and the following disclaimer.
8 *
9 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
10 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
11 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
12 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
13 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
14 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
15 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
16 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
17 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
18 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
19 * SUCH DAMAGE.
20 *
21 * patch - a program to apply diffs to original files
22 *
23 * -C option added in 1998, original code by Marc Espie, based on FreeBSD
24 * behaviour
25 *
26 * $OpenBSD: util.c,v 1.35 2010/07/24 01:10:12 ray Exp $
27 */
28
29#include <sys/stat.h>
30
31#include <ctype.h>
32#include <errno.h>
33#include <fcntl.h>
34#include <libgen.h>
35#include <limits.h>
36#include <paths.h>
37#include <signal.h>
38#include <stdarg.h>
39#include <stdlib.h>
40#include <stdio.h>
41#include <string.h>
42#include <unistd.h>
43
44#include "common.h"
45#include "util.h"
46#include "backupfile.h"
47#include "pathnames.h"
48
49/* Rename a file, copying it if necessary. */
50
51int
52move_file(const char *from, const char *to)
53{
54	int	fromfd;
55	ssize_t	i;
56
57	/* to stdout? */
58
59	if (strEQ(to, "-")) {
60#ifdef DEBUGGING
61		if (debug & 4)
62			say("Moving %s to stdout.\n", from);
63#endif
64		fromfd = open(from, O_RDONLY);
65		if (fromfd < 0)
66			pfatal("internal error, can't reopen %s", from);
67		while ((i = read(fromfd, buf, buf_size)) > 0)
68			if (write(STDOUT_FILENO, buf, i) != i)
69				pfatal("write failed");
70		close(fromfd);
71		return 0;
72	}
73	if (backup_file(to) < 0) {
74		say("Can't backup %s, output is in %s: %s\n", to, from,
75		    strerror(errno));
76		return -1;
77	}
78#ifdef DEBUGGING
79	if (debug & 4)
80		say("Moving %s to %s.\n", from, to);
81#endif
82	if (rename(from, to) < 0) {
83		if (errno != EXDEV || copy_file(from, to) < 0) {
84			say("Can't create %s, output is in %s: %s\n",
85			    to, from, strerror(errno));
86			return -1;
87		}
88	}
89	return 0;
90}
91
92/* Backup the original file.  */
93
94int
95backup_file(const char *orig)
96{
97	struct stat	filestat;
98	char		bakname[PATH_MAX], *s, *simplename;
99	dev_t		orig_device;
100	ino_t		orig_inode;
101
102	if (backup_type == none || stat(orig, &filestat) != 0)
103		return 0;			/* nothing to do */
104	/*
105	 * If the user used zero prefixes or suffixes, then
106	 * he doesn't want backups.  Yet we have to remove
107	 * orig to break possible hardlinks.
108	 */
109	if ((origprae && *origprae == 0) || *simple_backup_suffix == 0) {
110		unlink(orig);
111		return 0;
112	}
113	orig_device = filestat.st_dev;
114	orig_inode = filestat.st_ino;
115
116	if (origprae) {
117		if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
118		    strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
119			fatal("filename %s too long for buffer\n", origprae);
120	} else {
121		if ((s = find_backup_file_name(orig)) == NULL)
122			fatal("out of memory\n");
123		if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
124			fatal("filename %s too long for buffer\n", s);
125		free(s);
126	}
127
128	if ((simplename = strrchr(bakname, '/')) != NULL)
129		simplename = simplename + 1;
130	else
131		simplename = bakname;
132
133	/*
134	 * Find a backup name that is not the same file. Change the
135	 * first lowercase char into uppercase; if that isn't
136	 * sufficient, chop off the first char and try again.
137	 */
138	while (stat(bakname, &filestat) == 0 &&
139	    orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
140		/* Skip initial non-lowercase chars.  */
141		for (s = simplename; *s && !islower((unsigned char)*s); s++)
142			;
143		if (*s)
144			*s = toupper((unsigned char)*s);
145		else
146			memmove(simplename, simplename + 1,
147			    strlen(simplename + 1) + 1);
148	}
149#ifdef DEBUGGING
150	if (debug & 4)
151		say("Moving %s to %s.\n", orig, bakname);
152#endif
153	if (rename(orig, bakname) < 0) {
154		if (errno != EXDEV || copy_file(orig, bakname) < 0)
155			return -1;
156	}
157	return 0;
158}
159
160/*
161 * Copy a file.
162 */
163int
164copy_file(const char *from, const char *to)
165{
166	int	tofd, fromfd;
167	ssize_t	i;
168
169	tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
170	if (tofd < 0)
171		return -1;
172	fromfd = open(from, O_RDONLY, 0);
173	if (fromfd < 0)
174		pfatal("internal error, can't reopen %s", from);
175	while ((i = read(fromfd, buf, buf_size)) > 0)
176		if (write(tofd, buf, i) != i)
177			pfatal("write to %s failed", to);
178	close(fromfd);
179	close(tofd);
180	return 0;
181}
182
183/*
184 * Allocate a unique area for a string.
185 */
186char *
187savestr(const char *s)
188{
189	char	*rv;
190
191	if (!s)
192		s = "Oops";
193	rv = strdup(s);
194	if (rv == NULL) {
195		if (using_plan_a)
196			out_of_mem = true;
197		else
198			fatal("out of memory\n");
199	}
200	return rv;
201}
202
203/*
204 * Allocate a unique area for a string.  Call fatal if out of memory.
205 */
206char *
207xstrdup(const char *s)
208{
209	char	*rv;
210
211	if (!s)
212		s = "Oops";
213	rv = strdup(s);
214	if (rv == NULL)
215		fatal("out of memory\n");
216	return rv;
217}
218
219/*
220 * Vanilla terminal output (buffered).
221 */
222void
223say(const char *fmt, ...)
224{
225	va_list	ap;
226
227	va_start(ap, fmt);
228	vfprintf(stdout, fmt, ap);
229	va_end(ap);
230	fflush(stdout);
231}
232
233/*
234 * Terminal output, pun intended.
235 */
236void
237fatal(const char *fmt, ...)
238{
239	va_list	ap;
240
241	va_start(ap, fmt);
242	fprintf(stderr, "patch: **** ");
243	vfprintf(stderr, fmt, ap);
244	va_end(ap);
245	my_exit(2);
246}
247
248/*
249 * Say something from patch, something from the system, then silence . . .
250 */
251void
252pfatal(const char *fmt, ...)
253{
254	va_list	ap;
255	int	errnum = errno;
256
257	fprintf(stderr, "patch: **** ");
258	va_start(ap, fmt);
259	vfprintf(stderr, fmt, ap);
260	va_end(ap);
261	fprintf(stderr, ": %s\n", strerror(errnum));
262	my_exit(2);
263}
264
265/*
266 * Get a response from the user via /dev/tty
267 */
268void
269ask(const char *fmt, ...)
270{
271	va_list	ap;
272	ssize_t	nr = 0;
273	static	int ttyfd = -1;
274
275	va_start(ap, fmt);
276	vfprintf(stdout, fmt, ap);
277	va_end(ap);
278	fflush(stdout);
279	if (ttyfd < 0)
280		ttyfd = open(_PATH_TTY, O_RDONLY);
281	if (ttyfd >= 0) {
282		if ((nr = read(ttyfd, buf, buf_size)) > 0 &&
283		    buf[nr - 1] == '\n')
284			buf[nr - 1] = '\0';
285	}
286	if (ttyfd < 0 || nr <= 0) {
287		/* no tty or error reading, pretend user entered 'return' */
288		putchar('\n');
289		buf[0] = '\0';
290	}
291}
292
293/*
294 * How to handle certain events when not in a critical region.
295 */
296void
297set_signals(int reset)
298{
299	static sig_t	hupval, intval;
300
301	if (!reset) {
302		hupval = signal(SIGHUP, SIG_IGN);
303		if (hupval != SIG_IGN)
304			hupval = my_exit;
305		intval = signal(SIGINT, SIG_IGN);
306		if (intval != SIG_IGN)
307			intval = my_exit;
308	}
309	signal(SIGHUP, hupval);
310	signal(SIGINT, intval);
311}
312
313/*
314 * How to handle certain events when in a critical region.
315 */
316void
317ignore_signals(void)
318{
319	signal(SIGHUP, SIG_IGN);
320	signal(SIGINT, SIG_IGN);
321}
322
323/*
324 * Make sure we'll have the directories to create a file. If `striplast' is
325 * true, ignore the last element of `filename'.
326 */
327
328void
329makedirs(const char *filename, bool striplast)
330{
331	char	*tmpbuf;
332
333	if ((tmpbuf = strdup(filename)) == NULL)
334		fatal("out of memory\n");
335
336	if (striplast) {
337		char	*s = strrchr(tmpbuf, '/');
338		if (s == NULL) {
339			free(tmpbuf);
340			return;	/* nothing to be done */
341		}
342		*s = '\0';
343	}
344	if (mkpath(tmpbuf) != 0)
345		pfatal("creation of %s failed", tmpbuf);
346	free(tmpbuf);
347}
348
349/*
350 * Make filenames more reasonable.
351 */
352char *
353fetchname(const char *at, bool *exists, int strip_leading)
354{
355	char		*fullname, *name, *t;
356	int		sleading, tab;
357	struct stat	filestat;
358
359	if (at == NULL || *at == '\0')
360		return NULL;
361	while (isspace((unsigned char)*at))
362		at++;
363#ifdef DEBUGGING
364	if (debug & 128)
365		say("fetchname %s %d\n", at, strip_leading);
366#endif
367	/* So files can be created by diffing against /dev/null.  */
368	if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1)) {
369		*exists = true;
370		return NULL;
371	}
372	name = fullname = t = savestr(at);
373
374	tab = strchr(t, '\t') != NULL;
375	/* Strip off up to `strip_leading' path components and NUL terminate. */
376	for (sleading = strip_leading; *t != '\0' && ((tab && *t != '\t') ||
377	    !isspace((unsigned char)*t)); t++) {
378		if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
379			if (--sleading >= 0)
380				name = t + 1;
381	}
382	*t = '\0';
383
384	/*
385	 * If no -p option was given (957 is the default value!), we were
386	 * given a relative pathname, and the leading directories that we
387	 * just stripped off all exist, put them back on.
388	 */
389	if (strip_leading == 957 && name != fullname && *fullname != '/') {
390		name[-1] = '\0';
391		if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
392			name[-1] = '/';
393			name = fullname;
394		}
395	}
396	name = savestr(name);
397	free(fullname);
398
399	*exists = stat(name, &filestat) == 0;
400	return name;
401}
402
403void
404version(void)
405{
406	printf("patch 2.0-12u11 FreeBSD\n");
407	my_exit(EXIT_SUCCESS);
408}
409
410/*
411 * Exit with cleanup.
412 */
413void
414my_exit(int status)
415{
416	unlink(TMPINNAME);
417	if (!toutkeep)
418		unlink(TMPOUTNAME);
419	if (!trejkeep)
420		unlink(TMPREJNAME);
421	unlink(TMPPATNAME);
422	exit(status);
423}
424