xref: /netbsd/usr.bin/patch/util.c (revision 5631a155)
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  * $NetBSD: util.c,v 1.30 2021/05/25 11:25:59 cjep Exp $
5  */
6 
7 /*
8  * patch - a program to apply diffs to original files
9  *
10  * Copyright 1986, Larry Wall
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following condition is met:
14  * 1. Redistributions of source code must retain the above copyright notice,
15  * this condition and the following disclaimer.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
24  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
30  * behaviour
31  */
32 
33 #include <sys/cdefs.h>
34 __RCSID("$NetBSD: util.c,v 1.30 2021/05/25 11:25:59 cjep Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/stat.h>
38 
39 #include <ctype.h>
40 #include <errno.h>
41 #include <fcntl.h>
42 #include <libgen.h>
43 #include <signal.h>
44 #include <stdarg.h>
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "common.h"
51 #include "util.h"
52 #include "backupfile.h"
53 #include "pathnames.h"
54 
55 /* Rename a file, copying it if necessary. */
56 
57 int
move_file(const char * from,const char * to)58 move_file(const char *from, const char *to)
59 {
60 	int	fromfd;
61 	ssize_t	i;
62 
63 	/* to stdout? */
64 
65 	if (strEQ(to, "-")) {
66 #ifdef DEBUGGING
67 		if (debug & 4)
68 			say("Moving %s to stdout.\n", from);
69 #endif
70 		fromfd = open(from, O_RDONLY);
71 		if (fromfd < 0)
72 			pfatal("internal error, can't reopen %s", from);
73 		while ((i = read(fromfd, buf, bufsz)) > 0)
74 			if (write(STDOUT_FILENO, buf, i) != i)
75 				pfatal("write failed");
76 		close(fromfd);
77 		return 0;
78 	}
79 	if (backup_file(to) < 0) {
80 		say("Can't backup %s, output is in %s: %s\n", to, from,
81 		    strerror(errno));
82 		return -1;
83 	}
84 #ifdef DEBUGGING
85 	if (debug & 4)
86 		say("Moving %s to %s.\n", from, to);
87 #endif
88 	if (rename(from, to) < 0) {
89 		if (errno != EXDEV || copy_file(from, to) < 0) {
90 			say("Can't create %s, output is in %s: %s\n",
91 			    to, from, strerror(errno));
92 			return -1;
93 		}
94 	}
95 	return 0;
96 }
97 
98 /* Backup the original file.  */
99 
100 int
backup_file(const char * orig)101 backup_file(const char *orig)
102 {
103 	struct stat	filestat;
104 	char		bakname[MAXPATHLEN], *s, *simplename;
105 	dev_t		orig_device;
106 	ino_t		orig_inode;
107 
108 	if (backup_type == none || stat(orig, &filestat) != 0)
109 		return 0;			/* nothing to do */
110 	/*
111 	 * If the user used zero prefixes or suffixes, then
112 	 * he doesn't want backups.  Yet we have to remove
113 	 * orig to break possible hardlinks.
114 	 */
115 	if ((origprae && *origprae == 0) || *simple_backup_suffix == 0) {
116 		unlink(orig);
117 		return 0;
118 	}
119 	orig_device = filestat.st_dev;
120 	orig_inode = filestat.st_ino;
121 
122 	if (origprae) {
123 		if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
124 		    strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
125 			fatal("filename %s too long for buffer\n", origprae);
126 	} else {
127 		if ((s = find_backup_file_name(orig)) == NULL)
128 			fatal("out of memory\n");
129 		if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
130 			fatal("filename %s too long for buffer\n", s);
131 		free(s);
132 	}
133 
134 	if ((simplename = strrchr(bakname, '/')) != NULL)
135 		simplename = simplename + 1;
136 	else
137 		simplename = bakname;
138 
139 	/*
140 	 * Find a backup name that is not the same file. Change the
141 	 * first lowercase char into uppercase; if that isn't
142 	 * sufficient, chop off the first char and try again.
143 	 */
144 	while (stat(bakname, &filestat) == 0 &&
145 	    orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
146 		/* Skip initial non-lowercase chars.  */
147 		for (s = simplename; *s && !islower((unsigned char)*s); s++)
148 			;
149 		if (*s)
150 			*s = toupper((unsigned char)*s);
151 		else
152 			memmove(simplename, simplename + 1,
153 			    strlen(simplename + 1) + 1);
154 	}
155 #ifdef DEBUGGING
156 	if (debug & 4)
157 		say("Moving %s to %s.\n", orig, bakname);
158 #endif
159 	if (rename(orig, bakname) < 0) {
160 		if (errno != EXDEV || copy_file(orig, bakname) < 0)
161 			return -1;
162 	}
163 	return 0;
164 }
165 
166 /*
167  * Copy a file.
168  */
169 int
copy_file(const char * from,const char * to)170 copy_file(const char *from, const char *to)
171 {
172 	int	tofd, fromfd;
173 	ssize_t	i;
174 
175 	tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
176 	if (tofd < 0)
177 		return -1;
178 	fromfd = open(from, O_RDONLY, 0);
179 	if (fromfd < 0)
180 		pfatal("internal error, can't reopen %s", from);
181 	while ((i = read(fromfd, buf, bufsz)) > 0)
182 		if (write(tofd, buf, i) != i)
183 			pfatal("write to %s failed", to);
184 	close(fromfd);
185 	close(tofd);
186 	return 0;
187 }
188 
189 /*
190  * Allocate a unique area for a string.
191  */
192 char *
savestr(const char * s)193 savestr(const char *s)
194 {
195 	char	*rv;
196 
197 	if (!s)
198 		s = "Oops";
199 	rv = strdup(s);
200 	if (rv == NULL) {
201 		if (using_plan_a)
202 			out_of_mem = true;
203 		else
204 			fatal("out of memory\n");
205 	}
206 	return rv;
207 }
208 
209 /*
210  * Vanilla terminal output (buffered).
211  */
212 void
say(const char * fmt,...)213 say(const char *fmt, ...)
214 {
215 	va_list	ap;
216 
217 	va_start(ap, fmt);
218 	vfprintf(stderr, fmt, ap);
219 	va_end(ap);
220 	fflush(stderr);
221 }
222 
223 /*
224  * Terminal output, pun intended.
225  */
226 void
fatal(const char * fmt,...)227 fatal(const char *fmt, ...)
228 {
229 	va_list	ap;
230 
231 	va_start(ap, fmt);
232 	fprintf(stderr, "patch: **** ");
233 	vfprintf(stderr, fmt, ap);
234 	va_end(ap);
235 	my_exit(2);
236 }
237 
238 /*
239  * Say something from patch, something from the system, then silence . . .
240  */
241 void
pfatal(const char * fmt,...)242 pfatal(const char *fmt, ...)
243 {
244 	va_list	ap;
245 	int	errnum = errno;
246 
247 	fprintf(stderr, "patch: **** ");
248 	va_start(ap, fmt);
249 	vfprintf(stderr, fmt, ap);
250 	va_end(ap);
251 	fprintf(stderr, ": %s\n", strerror(errnum));
252 	my_exit(2);
253 }
254 
255 /*
256  * Get a response from the user via /dev/tty
257  */
258 void
ask(const char * fmt,...)259 ask(const char *fmt, ...)
260 {
261 	va_list	ap;
262 	ssize_t	nr = 0;
263 	static	int ttyfd = -1;
264 
265 	va_start(ap, fmt);
266 	vfprintf(stdout, fmt, ap);
267 	va_end(ap);
268 	fflush(stdout);
269 	if (ttyfd < 0)
270 		ttyfd = open(_PATH_TTY, O_RDONLY);
271 	if (ttyfd >= 0) {
272 		if ((nr = read(ttyfd, buf, bufsz)) > 0 &&
273 		    buf[nr - 1] == '\n')
274 			buf[nr - 1] = '\0';
275 	}
276 	if (ttyfd < 0 || nr <= 0) {
277 		/* no tty or error reading, pretend user entered 'return' */
278 		putchar('\n');
279 		buf[0] = '\0';
280 	}
281 }
282 
283 /*
284  * How to handle certain events when not in a critical region.
285  */
286 void
set_signals(int reset)287 set_signals(int reset)
288 {
289 	static sig_t	hupval, intval;
290 
291 	if (!reset) {
292 		hupval = signal(SIGHUP, SIG_IGN);
293 		if (hupval != SIG_IGN)
294 			hupval = my_exit;
295 		intval = signal(SIGINT, SIG_IGN);
296 		if (intval != SIG_IGN)
297 			intval = my_exit;
298 	}
299 	signal(SIGHUP, hupval);
300 	signal(SIGINT, intval);
301 }
302 
303 /*
304  * How to handle certain events when in a critical region.
305  */
306 void
ignore_signals(void)307 ignore_signals(void)
308 {
309 	signal(SIGHUP, SIG_IGN);
310 	signal(SIGINT, SIG_IGN);
311 }
312 
313 /*
314  * Make sure we'll have the directories to create a file. If `striplast' is
315  * true, ignore the last element of `filename'.
316  */
317 
318 void
makedirs(const char * filename,bool striplast)319 makedirs(const char *filename, bool striplast)
320 {
321 	char	*tmpbuf;
322 
323 	if ((tmpbuf = strdup(filename)) == NULL)
324 		fatal("out of memory\n");
325 
326 	if (striplast) {
327 		char	*s = strrchr(tmpbuf, '/');
328 		if (s == NULL) {
329 			free(tmpbuf);
330 			return;	/* nothing to be done */
331 		}
332 		*s = '\0';
333 	}
334 	if (mkpath(tmpbuf) != 0)
335 		pfatal("creation of %s failed", tmpbuf);
336 	free(tmpbuf);
337 }
338 
339 /*
340  * Make filenames more reasonable.
341  */
342 char *
fetchname(const char * at,bool * exists,int strip_leading)343 fetchname(const char *at, bool *exists, int strip_leading)
344 {
345 	char		*fullname, *name, *t;
346 	int		sleading, tab;
347 	struct stat	filestat;
348 
349 	if (at == NULL || *at == '\0')
350 		return NULL;
351 	while (isspace((unsigned char)*at))
352 		at++;
353 #ifdef DEBUGGING
354 	if (debug & 128)
355 		say("fetchname %s %d\n", at, strip_leading);
356 #endif
357 	/* So files can be created by diffing against /dev/null.  */
358 	if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
359 		return NULL;
360 	name = fullname = t = savestr(at);
361 
362 	tab = strchr(t, '\t') != NULL;
363 	/* Strip off up to `strip_leading' path components and NUL terminate. */
364 	for (sleading = strip_leading; *t != '\0' && ((tab && *t != '\t') ||
365 	    !isspace((unsigned char)*t)); t++) {
366 		if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
367 			if (--sleading >= 0)
368 				name = t + 1;
369 	}
370 	*t = '\0';
371 
372 	/*
373 	 * If no -p option was given (957 is the default value!), we were
374 	 * given a relative pathname, and the leading directories that we
375 	 * just stripped off all exist, put them back on.
376 	 */
377 	if (strip_leading == 957 && name != fullname && *fullname != '/') {
378 		name[-1] = '\0';
379 		if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
380 			name[-1] = '/';
381 			name = fullname;
382 		}
383 	}
384 	name = savestr(name);
385 	free(fullname);
386 
387 	*exists = stat(name, &filestat) == 0;
388 	return name;
389 }
390 
391 /*
392  * Takes the name returned by fetchname and looks in RCS/SCCS directories
393  * for a checked in version.
394  */
395 char *
checked_in(char * file)396 checked_in(char *file)
397 {
398 	char		*filebase, *filedir, tmpbuf[MAXPATHLEN];
399 	struct stat	filestat;
400 
401 	filebase = basename(file);
402 	filedir = dirname(file);
403 
404 #define try(f, a1, a2, a3) \
405 (snprintf(tmpbuf, sizeof tmpbuf, f, a1, a2, a3), stat(tmpbuf, &filestat) == 0)
406 
407 	if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
408 	    try("%s/RCS/%s%s", filedir, filebase, "") ||
409 	    try("%s/%s%s", filedir, filebase, RCSSUFFIX) ||
410 	    try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
411 	    try("%s/%s%s", filedir, SCCSPREFIX, filebase))
412 		return file;
413 
414 	return NULL;
415 }
416 
417 void
version(void)418 version(void)
419 {
420 	printf("Patch version 2.0-12u9-NetBSD\n");
421 	my_exit(EXIT_SUCCESS);
422 }
423 
424 /*
425  * Exit with cleanup.
426  */
427 void
my_exit(int status)428 my_exit(int status)
429 {
430 	unlink(TMPINNAME);
431 	if (!toutkeep)
432 		unlink(TMPOUTNAME);
433 	if (!trejkeep)
434 		unlink(TMPREJNAME);
435 	unlink(TMPPATNAME);
436 	exit(status);
437 }
438 
439 void *
pch_realloc(void * ptr,size_t number,size_t size)440 pch_realloc(void *ptr, size_t number, size_t size)
441 {
442 	if (number > SIZE_MAX / size) {
443 		errno = EOVERFLOW;
444 		return NULL;
445 	}
446 	return realloc(ptr, number * size);
447 }
448