xref: /freebsd/contrib/ntp/libntp/lib/isc/unix/file.c (revision 7ef62cebc2f965b0f640263e179276928885e33d)
1 /*
2  * Copyright (C) 2004, 2005, 2007, 2009, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2000-2002  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /*
19  * Portions Copyright (c) 1987, 1993
20  *      The Regents of the University of California.  All rights reserved.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the above copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  *      This product includes software developed by the University of
33  *      California, Berkeley and its contributors.
34  * 4. Neither the name of the University nor the names of its contributors
35  *    may be used to endorse or promote products derived from this software
36  *    without specific prior written permission.
37  *
38  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
39  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
41  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
42  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
43  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
44  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
46  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
47  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
49  */
50 
51 /* $Id$ */
52 
53 /*! \file */
54 
55 #include <config.h>
56 
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <limits.h>
60 #include <stdlib.h>
61 #include <time.h>		/* Required for utimes on some platforms. */
62 #include <unistd.h>		/* Required for mkstemp on NetBSD. */
63 
64 
65 #include <sys/stat.h>
66 #include <sys/time.h>
67 
68 #include <isc/dir.h>
69 #include <isc/file.h>
70 #include <isc/log.h>
71 #include <isc/mem.h>
72 #include <isc/random.h>
73 #include <isc/string.h>
74 #include <isc/time.h>
75 #include <isc/util.h>
76 
77 #include "errno2result.h"
78 #include "ntp_stdlib.h"		/* NTP change for strlcpy, strlcat */
79 
80 /*
81  * XXXDCL As the API for accessing file statistics undoubtedly gets expanded,
82  * it might be good to provide a mechanism that allows for the results
83  * of a previous stat() to be used again without having to do another stat,
84  * such as perl's mechanism of using "_" in place of a file name to indicate
85  * that the results of the last stat should be used.  But then you get into
86  * annoying MP issues.   BTW, Win32 has stat().
87  */
88 static isc_result_t
89 file_stats(const char *file, struct stat *stats) {
90 	isc_result_t result = ISC_R_SUCCESS;
91 
92 	REQUIRE(file != NULL);
93 	REQUIRE(stats != NULL);
94 
95 	if (stat(file, stats) != 0)
96 		result = isc__errno2result(errno);
97 
98 	return (result);
99 }
100 
101 isc_result_t
102 isc_file_getmodtime(const char *file, isc_time_t *itime) {
103 	isc_result_t result;
104 	struct stat stats;
105 
106 	REQUIRE(file != NULL);
107 	REQUIRE(itime != NULL);
108 
109 	result = file_stats(file, &stats);
110 
111 	if (result == ISC_R_SUCCESS)
112 		/*
113 		 * XXXDCL some operating systems provide nanoseconds, too,
114 		 * such as BSD/OS via st_mtimespec.
115 		 */
116 		isc_time_set(itime, stats.st_mtime, 0);
117 
118 	return (result);
119 }
120 
121 isc_result_t
122 isc_file_settime(const char *file, isc_time_t *itime) {
123 	struct timeval times[2];
124 
125 	REQUIRE(file != NULL && itime != NULL);
126 
127 	/*
128 	 * tv_sec is at least a 32 bit quantity on all platforms we're
129 	 * dealing with, but it is signed on most (all?) of them,
130 	 * so we need to make sure the high bit isn't set.  This unfortunately
131 	 * loses when either:
132 	 *   * tv_sec becomes a signed 64 bit integer but long is 32 bits
133 	 *	and isc_time_seconds > LONG_MAX, or
134 	 *   * isc_time_seconds is changed to be > 32 bits but long is 32 bits
135 	 *      and isc_time_seconds has at least 33 significant bits.
136 	 */
137 	times[0].tv_sec = times[1].tv_sec = (long)isc_time_seconds(itime);
138 
139 	/*
140 	 * Here is the real check for the high bit being set.
141 	 */
142 	if ((times[0].tv_sec &
143 	     (1ULL << (sizeof(times[0].tv_sec) * CHAR_BIT - 1))) != 0)
144 		return (ISC_R_RANGE);
145 
146 	/*
147 	 * isc_time_nanoseconds guarantees a value that divided by 1000 will
148 	 * fit into the minimum possible size tv_usec field.  Unfortunately,
149 	 * we don't know what that type is so can't cast directly ... but
150 	 * we can at least cast to signed so the IRIX compiler shuts up.
151 	 */
152 	times[0].tv_usec = times[1].tv_usec =
153 		(isc_int32_t)(isc_time_nanoseconds(itime) / 1000);
154 
155 	if (utimes(file, times) < 0)
156 		return (isc__errno2result(errno));
157 
158 	return (ISC_R_SUCCESS);
159 }
160 
161 #undef TEMPLATE
162 #define TEMPLATE "tmp-XXXXXXXXXX" /*%< 14 characters. */
163 
164 isc_result_t
165 isc_file_mktemplate(const char *path, char *buf, size_t buflen) {
166 	return (isc_file_template(path, TEMPLATE, buf, buflen));
167 }
168 
169 isc_result_t
170 isc_file_template(const char *path, const char *templet, char *buf,
171 			size_t buflen) {
172 	char *s;
173 
174 	REQUIRE(path != NULL);
175 	REQUIRE(templet != NULL);
176 	REQUIRE(buf != NULL);
177 
178 	s = strrchr(templet, '/');
179 	if (s != NULL)
180 		templet = s + 1;
181 
182 	s = strrchr(path, '/');
183 
184 	if (s != NULL) {
185 		if ((s - path + 1 + strlen(templet) + 1) > buflen)
186 			return (ISC_R_NOSPACE);
187 
188 		strlcpy(buf, path, buflen);
189 		buf[s - path + 1] = '\0';
190 		strlcat(buf, templet, buflen);
191 	} else {
192 		if ((strlen(templet) + 1) > buflen)
193 			return (ISC_R_NOSPACE);
194 
195 		strlcpy(buf, templet, buflen);
196 	}
197 
198 	return (ISC_R_SUCCESS);
199 }
200 
201 static char alphnum[] =
202 	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
203 
204 isc_result_t
205 isc_file_renameunique(const char *file, char *templet) {
206 	char *x;
207 	char *cp;
208 	isc_uint32_t which;
209 
210 	REQUIRE(file != NULL);
211 	REQUIRE(templet != NULL);
212 
213 	cp = templet;
214 	while (*cp != '\0')
215 		cp++;
216 	if (cp == templet)
217 		return (ISC_R_FAILURE);
218 
219 	x = cp--;
220 	while (cp >= templet && *cp == 'X') {
221 		isc_random_get(&which);
222 		*cp = alphnum[which % (sizeof(alphnum) - 1)];
223 		x = cp--;
224 	}
225 	while (link(file, templet) == -1) {
226 		if (errno != EEXIST)
227 			return (isc__errno2result(errno));
228 		for (cp = x;;) {
229 			char *t;
230 			if (*cp == '\0')
231 				return (ISC_R_FAILURE);
232 			t = strchr(alphnum, *cp);
233 			if (t == NULL || *++t == '\0')
234 				*cp++ = alphnum[0];
235 			else {
236 				*cp = *t;
237 				break;
238 			}
239 		}
240 	}
241 	if (unlink(file) < 0)
242 		if (errno != ENOENT)
243 			return (isc__errno2result(errno));
244 	return (ISC_R_SUCCESS);
245 }
246 
247 isc_result_t
248 isc_file_openunique(char *templet, FILE **fp) {
249 	int mode = S_IWUSR|S_IRUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
250 	return (isc_file_openuniquemode(templet, mode, fp));
251 }
252 
253 isc_result_t
254 isc_file_openuniqueprivate(char *templet, FILE **fp) {
255 	int mode = S_IWUSR|S_IRUSR;
256 	return (isc_file_openuniquemode(templet, mode, fp));
257 }
258 
259 isc_result_t
260 isc_file_openuniquemode(char *templet, int mode, FILE **fp) {
261 	int fd;
262 	FILE *f;
263 	isc_result_t result = ISC_R_SUCCESS;
264 	char *x;
265 	char *cp;
266 	isc_uint32_t which;
267 
268 	REQUIRE(templet != NULL);
269 	REQUIRE(fp != NULL && *fp == NULL);
270 
271 	cp = templet;
272 	while (*cp != '\0')
273 		cp++;
274 	if (cp == templet)
275 		return (ISC_R_FAILURE);
276 
277 	x = cp--;
278 	while (cp >= templet && *cp == 'X') {
279 		isc_random_get(&which);
280 		*cp = alphnum[which % (sizeof(alphnum) - 1)];
281 		x = cp--;
282 	}
283 
284 
285 	while ((fd = open(templet, O_RDWR|O_CREAT|O_EXCL, mode)) == -1) {
286 		if (errno != EEXIST)
287 			return (isc__errno2result(errno));
288 		for (cp = x;;) {
289 			char *t;
290 			if (*cp == '\0')
291 				return (ISC_R_FAILURE);
292 			t = strchr(alphnum, *cp);
293 			if (t == NULL || *++t == '\0')
294 				*cp++ = alphnum[0];
295 			else {
296 				*cp = *t;
297 				break;
298 			}
299 		}
300 	}
301 	f = fdopen(fd, "w+");
302 	if (f == NULL) {
303 		result = isc__errno2result(errno);
304 		if (remove(templet) < 0) {
305 			isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
306 				      ISC_LOGMODULE_FILE, ISC_LOG_ERROR,
307 				      "remove '%s': failed", templet);
308 		}
309 		(void)close(fd);
310 	} else
311 		*fp = f;
312 
313 	return (result);
314 }
315 
316 isc_result_t
317 isc_file_remove(const char *filename) {
318 	int r;
319 
320 	REQUIRE(filename != NULL);
321 
322 	r = unlink(filename);
323 	if (r == 0)
324 		return (ISC_R_SUCCESS);
325 	else
326 		return (isc__errno2result(errno));
327 }
328 
329 isc_result_t
330 isc_file_rename(const char *oldname, const char *newname) {
331 	int r;
332 
333 	REQUIRE(oldname != NULL);
334 	REQUIRE(newname != NULL);
335 
336 	r = rename(oldname, newname);
337 	if (r == 0)
338 		return (ISC_R_SUCCESS);
339 	else
340 		return (isc__errno2result(errno));
341 }
342 
343 isc_boolean_t
344 isc_file_exists(const char *pathname) {
345 	struct stat stats;
346 
347 	REQUIRE(pathname != NULL);
348 
349 	return (ISC_TF(file_stats(pathname, &stats) == ISC_R_SUCCESS));
350 }
351 
352 isc_result_t
353 isc_file_isplainfile(const char *filename) {
354 	/*
355 	 * This function returns success if filename is a plain file.
356 	 */
357 	struct stat filestat;
358 	memset(&filestat,0,sizeof(struct stat));
359 
360 	if ((stat(filename, &filestat)) == -1)
361 		return(isc__errno2result(errno));
362 
363 	if(! S_ISREG(filestat.st_mode))
364 		return(ISC_R_INVALIDFILE);
365 
366 	return(ISC_R_SUCCESS);
367 }
368 
369 isc_boolean_t
370 isc_file_isabsolute(const char *filename) {
371 	REQUIRE(filename != NULL);
372 	return (ISC_TF(filename[0] == '/'));
373 }
374 
375 isc_boolean_t
376 isc_file_iscurrentdir(const char *filename) {
377 	REQUIRE(filename != NULL);
378 	return (ISC_TF(filename[0] == '.' && filename[1] == '\0'));
379 }
380 
381 isc_boolean_t
382 isc_file_ischdiridempotent(const char *filename) {
383 	REQUIRE(filename != NULL);
384 	if (isc_file_isabsolute(filename))
385 		return (ISC_TRUE);
386 	if (isc_file_iscurrentdir(filename))
387 		return (ISC_TRUE);
388 	return (ISC_FALSE);
389 }
390 
391 const char *
392 isc_file_basename(const char *filename) {
393 	char *s;
394 
395 	REQUIRE(filename != NULL);
396 
397 	s = strrchr(filename, '/');
398 	if (s == NULL)
399 		return (filename);
400 
401 	return (s + 1);
402 }
403 
404 isc_result_t
405 isc_file_progname(const char *filename, char *buf, size_t buflen) {
406 	const char *base;
407 	size_t len;
408 
409 	REQUIRE(filename != NULL);
410 	REQUIRE(buf != NULL);
411 
412 	base = isc_file_basename(filename);
413 	len = strlen(base) + 1;
414 
415 	if (len > buflen)
416 		return (ISC_R_NOSPACE);
417 	memcpy(buf, base, len);
418 
419 	return (ISC_R_SUCCESS);
420 }
421 
422 /*
423  * Put the absolute name of the current directory into 'dirname', which is
424  * a buffer of at least 'length' characters.  End the string with the
425  * appropriate path separator, such that the final product could be
426  * concatenated with a relative pathname to make a valid pathname string.
427  */
428 static isc_result_t
429 dir_current(char *dirname, size_t length) {
430 	char *cwd;
431 	isc_result_t result = ISC_R_SUCCESS;
432 
433 	REQUIRE(dirname != NULL);
434 	REQUIRE(length > 0U);
435 
436 	cwd = getcwd(dirname, length);
437 
438 	if (cwd == NULL) {
439 		if (errno == ERANGE)
440 			result = ISC_R_NOSPACE;
441 		else
442 			result = isc__errno2result(errno);
443 	} else {
444 		if (strlen(dirname) + 1 == length)
445 			result = ISC_R_NOSPACE;
446 		else if (dirname[1] != '\0')
447 			strlcat(dirname, "/", length);
448 	}
449 
450 	return (result);
451 }
452 
453 isc_result_t
454 isc_file_absolutepath(const char *filename, char *path, size_t pathlen) {
455 	isc_result_t result;
456 	result = dir_current(path, pathlen);
457 	if (result != ISC_R_SUCCESS)
458 		return (result);
459 	if (strlen(path) + strlen(filename) + 1 > pathlen)
460 		return (ISC_R_NOSPACE);
461 	strlcat(path, filename, pathlen);
462 	return (ISC_R_SUCCESS);
463 }
464 
465 isc_result_t
466 isc_file_truncate(const char *filename, isc_offset_t size) {
467 	isc_result_t result = ISC_R_SUCCESS;
468 
469 	if (truncate(filename, size) < 0)
470 		result = isc__errno2result(errno);
471 	return (result);
472 }
473 
474 isc_result_t
475 isc_file_safecreate(const char *filename, FILE **fp) {
476 	isc_result_t result;
477 	int flags;
478 	struct stat sb;
479 	FILE *f;
480 	int fd;
481 
482 	REQUIRE(filename != NULL);
483 	REQUIRE(fp != NULL && *fp == NULL);
484 
485 	result = file_stats(filename, &sb);
486 	if (result == ISC_R_SUCCESS) {
487 		if ((sb.st_mode & S_IFREG) == 0)
488 			return (ISC_R_INVALIDFILE);
489 		flags = O_WRONLY | O_TRUNC;
490 	} else if (result == ISC_R_FILENOTFOUND) {
491 		flags = O_WRONLY | O_CREAT | O_EXCL;
492 	} else
493 		return (result);
494 
495 	fd = open(filename, flags, S_IRUSR | S_IWUSR);
496 	if (fd == -1)
497 		return (isc__errno2result(errno));
498 
499 	f = fdopen(fd, "w");
500 	if (f == NULL) {
501 		result = isc__errno2result(errno);
502 		close(fd);
503 		return (result);
504 	}
505 
506 	*fp = f;
507 	return (ISC_R_SUCCESS);
508 }
509 
510 isc_result_t
511 isc_file_splitpath(isc_mem_t *mctx, char *path, char **dirnam, char **basenam)
512 {
513 	char *dir, *file, *slash;
514 
515 	REQUIRE(path != NULL);
516 
517 	slash = strrchr(path, '/');
518 
519 	if (slash == path) {
520 		file = ++slash;
521 		dir = isc_mem_strdup(mctx, "/");
522 	} else if (slash != NULL) {
523 		file = ++slash;
524 		dir = isc_mem_allocate(mctx, slash - path);
525 		if (dir != NULL)
526 			strlcpy(dir, path, slash - path);
527 	} else {
528 		file = path;
529 		dir = isc_mem_strdup(mctx, ".");
530 	}
531 
532 	if (dir == NULL)
533 		return (ISC_R_NOMEMORY);
534 
535 	if (*file == '\0') {
536 		isc_mem_free(mctx, dir);
537 		return (ISC_R_INVALIDFILE);
538 	}
539 
540 	*dirnam = dir;
541 	*basenam = file;
542 
543 	return (ISC_R_SUCCESS);
544 }
545