xref: /netbsd-src/usr.bin/newsyslog/newsyslog.c (revision d20841bb642898112fe68f0ad3f7b26dddf56f07)
1 /*	$NetBSD: newsyslog.c,v 1.47 2003/10/13 07:28:52 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1999, 2000 Andrew Doran <ad@NetBSD.org>
5  * 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER 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  */
29 
30 /*
31  * This file contains changes from the Open Software Foundation.
32  */
33 
34 /*
35  * Copyright 1988, 1989 by the Massachusetts Institute of Technology
36  *
37  * Permission to use, copy, modify, and distribute this software
38  * and its documentation for any purpose and without fee is
39  * hereby granted, provided that the above copyright notice
40  * appear in all copies and that both that copyright notice and
41  * this permission notice appear in supporting documentation,
42  * and that the names of M.I.T. and the M.I.T. S.I.P.B. not be
43  * used in advertising or publicity pertaining to distribution
44  * of the software without specific, written prior permission.
45  * M.I.T. and the M.I.T. S.I.P.B. make no representations about
46  * the suitability of this software for any purpose.  It is
47  * provided "as is" without express or implied warranty.
48  *
49  */
50 
51 /*
52  * newsyslog(8) - a program to roll over log files provided that specified
53  * critera are met, optionally preserving a number of historical log files.
54  */
55 
56 #include <sys/cdefs.h>
57 #ifndef lint
58 __RCSID("$NetBSD: newsyslog.c,v 1.47 2003/10/13 07:28:52 lukem Exp $");
59 #endif /* not lint */
60 
61 #include <sys/types.h>
62 #include <sys/time.h>
63 #include <sys/stat.h>
64 #include <sys/param.h>
65 #include <sys/wait.h>
66 
67 #include <ctype.h>
68 #include <fcntl.h>
69 #include <grp.h>
70 #include <pwd.h>
71 #include <signal.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <stdarg.h>
75 #include <string.h>
76 #include <time.h>
77 #include <unistd.h>
78 #include <errno.h>
79 #include <err.h>
80 #include <paths.h>
81 
82 #include "pathnames.h"
83 
84 #define	PRHDRINFO(x)	((void)(verbose ? printf x : 0))
85 #define	PRINFO(x)	((void)(verbose ? printf("  ") + printf x : 0))
86 
87 #define	CE_COMPRESS	0x01	/* Compress the archived log files */
88 #define	CE_BINARY	0x02	/* Logfile is a binary file/non-syslog */
89 #define	CE_NOSIGNAL	0x04	/* Don't send a signal when trimmed */
90 #define	CE_CREATE	0x08	/* Create log file if none exists */
91 #define	CE_PLAIN0	0x10	/* Do not compress zero'th history file */
92 
93 struct conf_entry {
94 	uid_t	uid;			/* Owner of log */
95 	gid_t	gid;			/* Group of log */
96 	mode_t	mode;			/* File permissions */
97 	int	numhist;		/* Number of historical logs to keep */
98 	size_t	maxsize;		/* Maximum log size */
99 	int	maxage;			/* Hours between log trimming */
100 	time_t	trimat;			/* Specific trim time */
101 	int	flags;			/* Flags (CE_*) */
102 	int	signum;			/* Signal to send */
103 	char	pidfile[MAXPATHLEN];	/* File containing PID to signal */
104 	char	logfile[MAXPATHLEN];	/* Path to log file */
105 };
106 
107 int	verbose;			/* Be verbose */
108 int	noaction;			/* Take no action */
109 int	nosignal;			/* Do not send signals */
110 char    hostname[MAXHOSTNAMELEN + 1];	/* Hostname, stripped of domain */
111 uid_t	myeuid;				/* EUID we are running with */
112 
113 int	getsig(const char *);
114 int	isnumber(const char *);
115 int	main(int, char **);
116 int	parse_cfgline(struct conf_entry *, FILE *, size_t *);
117 time_t	parse_iso8601(char *);
118 time_t	parse_dwm(char *);
119 int	parse_userspec(const char *, struct passwd **, struct group **);
120 pid_t	readpidfile(const char *);
121 void	usage(void);
122 
123 void	log_compress(struct conf_entry *, const char *);
124 void	log_create(struct conf_entry *);
125 void	log_examine(struct conf_entry *, int);
126 void	log_trim(struct conf_entry *);
127 void	log_trimmed(struct conf_entry *);
128 
129 /*
130  * Program entry point.
131  */
132 int
133 main(int argc, char **argv)
134 {
135 	struct conf_entry log;
136 	FILE *fd;
137 	char *p, *cfile;
138 	int c, needroot, i, force;
139 	size_t lineno;
140 
141 	force = 0;
142 	needroot = 1;
143 	cfile = _PATH_NEWSYSLOGCONF;
144 
145 	gethostname(hostname, sizeof(hostname));
146 	hostname[sizeof(hostname) - 1] = '\0';
147 
148 	/* Truncate domain. */
149 	if ((p = strchr(hostname, '.')) != NULL)
150 		*p = '\0';
151 
152 	/* Parse command line options. */
153 	while ((c = getopt(argc, argv, "f:nrsvF")) != -1) {
154 		switch (c) {
155 		case 'f':
156 			cfile = optarg;
157 			break;
158 		case 'n':
159 			noaction = 1;
160 			verbose = 1;
161 			break;
162 		case 'r':
163 			needroot = 0;
164 			break;
165 		case 's':
166 			nosignal = 1;
167 			break;
168 		case 'v':
169 			verbose = 1;
170 			break;
171 		case 'F':
172 			force = 1;
173 			break;
174 		default:
175 			usage();
176 			/* NOTREACHED */
177 		}
178 	}
179 
180 	myeuid = geteuid();
181 	if (needroot && myeuid != 0)
182 		errx(EXIT_FAILURE, "must be run as root");
183 
184 	argc -= optind;
185 	argv += optind;
186 
187 	if (strcmp(cfile, "-") == 0)
188 		fd = stdin;
189 	else if ((fd = fopen(cfile, "rt")) == NULL)
190 		err(EXIT_FAILURE, "%s", cfile);
191 
192 	for (lineno = 0; !parse_cfgline(&log, fd, &lineno);) {
193 		/*
194 		 * If specific log files were specified, touch only
195 		 * those.
196 		 */
197 		if (argc != 0) {
198 			for (i = 0; i < argc; i++)
199 				if (strcmp(log.logfile, argv[i]) == 0)
200 					break;
201 			if (i == argc)
202 				continue;
203 		}
204 		log_examine(&log, force);
205 	}
206 
207 	if (fd != stdin)
208 		fclose(fd);
209 
210 	exit(EXIT_SUCCESS);
211 	/* NOTREACHED */
212 }
213 
214 /*
215  * Parse a single line from the configuration file.
216  */
217 int
218 parse_cfgline(struct conf_entry *log, FILE *fd, size_t *_lineno)
219 {
220 	char *line, *q, **ap, *argv[10];
221 	struct passwd *pw;
222 	struct group *gr;
223 	int nf, lineno, i, rv;
224 
225 	rv = -1;
226 	line = NULL;
227 
228 	/* Place the white-space separated fields into an array. */
229 	do {
230 		if (line != NULL)
231 			free(line);
232 		if ((line = fparseln(fd, NULL, _lineno, NULL, 0)) == NULL)
233 			return (rv);
234 		lineno = (int)*_lineno;
235 
236 		for (ap = argv, nf = 0; (*ap = strsep(&line, " \t")) != NULL;)
237 			if (**ap != '\0') {
238 				if (++nf == sizeof(argv) / sizeof(argv[0])) {
239 					warnx("config line %d: "
240 					    "too many fields", lineno);
241 					goto bad;
242 				}
243 				ap++;
244 			}
245 	} while (nf == 0);
246 
247 	if (nf < 6)
248 		errx(EXIT_FAILURE, "config line %d: too few fields", lineno);
249 
250 	memset(log, 0, sizeof(*log));
251 
252 	/* logfile_name */
253 	ap = argv;
254 	strlcpy(log->logfile, *ap++, sizeof(log->logfile));
255 	if (log->logfile[0] != '/')
256 		errx(EXIT_FAILURE,
257 		    "config line %d: logfile must have a full path", lineno);
258 
259 	/* owner:group */
260 	if (strchr(*ap, ':') != NULL || strchr(*ap, '.') != NULL) {
261 		if (parse_userspec(*ap++, &pw, &gr)) {
262 			warnx("config line %d: unknown user/group", lineno);
263 			goto bad;
264 		}
265 
266 		/*
267 		 * We may only change the file's owner as non-root.
268 		 */
269 		if (myeuid != 0) {
270 			if (pw->pw_uid != myeuid)
271 				errx(EXIT_FAILURE, "config line %d: user:group "
272 				    "as non-root must match current user",
273 				    lineno);
274 			log->uid = (uid_t)-1;
275 		} else
276 			log->uid = pw->pw_uid;
277 		log->gid = gr->gr_gid;
278 		if (nf < 7)
279 			errx(EXIT_FAILURE, "config line %d: too few fields",
280 			    lineno);
281 	} else if (myeuid != 0) {
282 		log->uid = (uid_t)-1;
283 		log->gid = getegid();
284 	}
285 
286 	/* mode */
287 	if (sscanf(*ap++, "%o", &i) != 1) {
288 		warnx("config line %d: bad permissions", lineno);
289 		goto bad;
290 	}
291 	log->mode = (mode_t)i;
292 
293 	/* count */
294 	if (sscanf(*ap++, "%d", &log->numhist) != 1) {
295 		warnx("config line %d: bad log count", lineno);
296 		goto bad;
297 	}
298 
299 	/* size */
300 	if (isdigit(**ap)) {
301 		log->maxsize = (int)strtol(*ap, &q, 0);
302 		if (*q != '\0') {
303 			warnx("config line %d: bad log size", lineno);
304 			goto bad;
305 		}
306 	} else if (**ap == '*')
307 		log->maxsize = (size_t)-1;
308 	else {
309 		warnx("config line %d: bad log size", lineno);
310 		goto bad;
311 	}
312 	ap++;
313 
314 	/* when */
315 	log->maxage = -1;
316 	log->trimat = (time_t)-1;
317 	q = *ap++;
318 
319 	if (strcmp(q, "*") != 0) {
320 		if (isdigit(*q))
321 			log->maxage = (int)strtol(q, &q, 10);
322 
323 		/*
324 		 * One class of periodic interval specification can follow a
325 		 * maximum age specification.  Handle it.
326 		 */
327 		if (*q == '@') {
328 			log->trimat = parse_iso8601(q + 1);
329 			if (log->trimat == (time_t)-1) {
330 				warnx("config line %d: bad trim time", lineno);
331 				goto bad;
332 			}
333 		} else if (*q == '$') {
334 			if ((log->trimat = parse_dwm(q + 1)) == (time_t)-1) {
335 				warnx("config line %d: bad trim time", lineno);
336 				goto bad;
337 			}
338 		} else if (log->maxage == -1) {
339 			warnx("config line %d: bad log age", lineno);
340 			goto bad;
341 		}
342 	}
343 
344 	/* flags */
345 	log->flags = (nosignal ? CE_NOSIGNAL : 0);
346 
347 	for (q = *ap++; q != NULL && *q != '\0'; q++) {
348 		switch (tolower(*q)) {
349 		case 'b':
350 			log->flags |= CE_BINARY;
351 			break;
352 		case 'c':
353 			log->flags |= CE_CREATE;
354 			break;
355 		case 'n':
356 			log->flags |= CE_NOSIGNAL;
357 			break;
358 		case 'p':
359 			log->flags |= CE_PLAIN0;
360 			break;
361 		case 'z':
362 			log->flags |= CE_COMPRESS;
363 			break;
364 		case '-':
365 			break;
366 		default:
367 			warnx("config line %d: bad flags", lineno);
368 			goto bad;
369 		}
370 	}
371 
372 	/* path_to_pidfile */
373 	if (*ap != NULL && **ap == '/')
374 		strlcpy(log->pidfile, *ap++, sizeof(log->pidfile));
375 	else
376 		log->pidfile[0] = '\0';
377 
378 	/* sigtype */
379 	if (*ap != NULL) {
380 		if ((log->signum = getsig(*ap++)) < 0) {
381 			warnx("config line %d: bad signal type", lineno);
382 			goto bad;
383 		}
384 	} else
385 		log->signum = SIGHUP;
386 
387 	rv = 0;
388 
389 bad:
390 	free(line);
391 	return (rv);
392 }
393 
394 /*
395  * Examine a log file.  If the trim conditions are met, call log_trim() to
396  * trim the log file.
397  */
398 void
399 log_examine(struct conf_entry *log, int force)
400 {
401 	struct stat sb;
402 	size_t size;
403 	int age, trim;
404 	char tmp[MAXPATHLEN];
405 	const char *reason;
406 	time_t now;
407 
408 	now = time(NULL);
409 
410 	PRHDRINFO(("\n%s <%d%s>: ", log->logfile, log->numhist,
411 	    (log->flags & CE_COMPRESS) != 0 ? "Z" : ""));
412 
413 	/*
414 	 * stat() the logfile.  If it doesn't exist and the `c' flag has
415 	 * been specified, create it.  If it doesn't exist and the `c' flag
416 	 * hasn't been specified, give up.
417 	 */
418 	if (stat(log->logfile, &sb) < 0) {
419 		if (errno == ENOENT && (log->flags & CE_CREATE) != 0) {
420 			PRHDRINFO(("creating; "));
421 			if (!noaction)
422 				log_create(log);
423 			else {
424 				PRHDRINFO(("can't proceed with `-n'\n"));
425 				return;
426 			}
427 			if (stat(log->logfile, &sb))
428 				err(EXIT_FAILURE, "%s", log->logfile);
429 		} else if (errno == ENOENT) {
430 			PRHDRINFO(("does not exist --> skip log\n"));
431 			return;
432 		} else if (errno != 0)
433 			err(EXIT_FAILURE, "%s", log->logfile);
434 	}
435 
436 	if (!S_ISREG(sb.st_mode)) {
437 		PRHDRINFO(("not a regular file --> skip log\n"));
438 		return;
439 	}
440 
441 	/* Size of the log file in kB. */
442 	size = ((size_t)sb.st_blocks * S_BLKSIZE) >> 10;
443 
444 	/*
445 	 * Get the age (expressed in hours) of the current log file with
446 	 * respect to the newest historical log file.
447 	 */
448 	strlcpy(tmp, log->logfile, sizeof(tmp));
449 	strlcat(tmp, ".0", sizeof(tmp));
450 	if (stat(tmp, &sb) < 0) {
451 		strlcat(tmp, ".gz", sizeof(tmp));
452 		if (stat(tmp, &sb) < 0)
453 			age = -1;
454 		else
455 			age = (int)(now - sb.st_mtime + 1800) / 3600;
456 	} else
457 		age = (int)(now - sb.st_mtime + 1800) / 3600;
458 
459 	/*
460 	 * Examine the set of given trim conditions and if any one is met,
461 	 * trim the log.
462 	 *
463 	 * Note: if `maxage' or `trimat' is used as a trim condition, we
464 	 * need at least one historical log file to determine the `age' of
465 	 * the active log file.  WRT `trimat', we will trim up to one hour
466 	 * after the specific trim time has passed - we need to know if
467 	 * we've trimmed to meet that condition with a previous invocation
468 	 * of newsyslog(8).
469 	 */
470 	if (log->maxage >= 0 && (age >= log->maxage || age < 0)) {
471 		trim = 1;
472 		reason = "log age > interval";
473 	} else if (size >= log->maxsize) {
474 		trim = 1;
475 		reason = "log size > size";
476 	} else if (log->trimat != (time_t)-1 && now >= log->trimat &&
477 		   (age == -1 || age > 1) &&
478 		   difftime(now, log->trimat) < 60 * 60) {
479 		trim = 1;
480 		reason = "specific trim time";
481 	} else {
482 		trim = force;
483 		reason = "trim forced";
484 	}
485 
486 	if (trim) {
487 		PRHDRINFO(("--> trim log (%s)\n", reason));
488 		log_trim(log);
489 	} else
490 		PRHDRINFO(("--> skip log (trim conditions not met)\n"));
491 }
492 
493 /*
494  * Trim the specified log file.
495  */
496 void
497 log_trim(struct conf_entry *log)
498 {
499 	char file1[MAXPATHLEN], file2[MAXPATHLEN];
500 	int i;
501 	struct stat st;
502 	pid_t pid;
503 
504 	if (log->numhist != 0) {
505 		/* Remove oldest historical log. */
506 		snprintf(file1, sizeof(file1), "%s.%d", log->logfile,
507 		    log->numhist - 1);
508 
509 		PRINFO(("rm -f %s\n", file1));
510 		if (!noaction)
511 			unlink(file1);
512 		strlcat(file1, ".gz", sizeof(file1));
513 		PRINFO(("rm -f %s\n", file1));
514 		if (!noaction)
515 			unlink(file1);
516 	}
517 
518 	/* Move down log files. */
519 	for (i = log->numhist - 1; i > 0; i--) {
520 		snprintf(file1, sizeof(file1), "%s.%d", log->logfile, i - 1);
521 		snprintf(file2, sizeof(file2), "%s.%d", log->logfile, i);
522 
523 		if (lstat(file1, &st) != 0) {
524 			strlcat(file1, ".gz", sizeof(file1));
525 			strlcat(file2, ".gz", sizeof(file2));
526 			if (lstat(file1, &st) != 0)
527 				continue;
528 		}
529 
530 		PRINFO(("mv %s %s\n", file1, file2));
531 		if (!noaction)
532 			if (rename(file1, file2))
533 				err(EXIT_FAILURE, "%s", file1);
534 		PRINFO(("chmod %o %s\n", log->mode, file2));
535 		if (!noaction)
536 			if (chmod(file2, log->mode))
537 				err(EXIT_FAILURE, "%s", file2);
538 		PRINFO(("chown %d:%d %s\n", log->uid, log->gid,
539 		    file2));
540 		if (!noaction)
541 			if (chown(file2, log->uid, log->gid))
542 				err(EXIT_FAILURE, "%s", file2);
543 	}
544 
545 	/*
546 	 * If a historical log file isn't compressed, and 'z' has been
547 	 * specified, compress it.  (This is convenient, but is also needed
548 	 * if 'p' has been specified.)  It should be noted that gzip(1)
549 	 * preserves file ownership and file mode.
550 	 */
551 	if ((log->flags & CE_COMPRESS) != 0) {
552 		for (i = (log->flags & CE_PLAIN0) != 0; i < log->numhist; i++) {
553 			snprintf(file1, sizeof(file1), "%s.%d", log->logfile, i);
554 			if (lstat(file1, &st) != 0)
555 				continue;
556 			snprintf(file2, sizeof(file2), "%s.gz", file1);
557 			if (lstat(file2, &st) == 0)
558 				continue;
559 			log_compress(log, file1);
560 		}
561 	}
562 
563 	log_trimmed(log);
564 
565 	/* Create the historical log file if we're maintaining history. */
566 	if (log->numhist == 0) {
567 		PRINFO(("rm -f %s\n", log->logfile));
568 		if (!noaction)
569 			if (unlink(log->logfile))
570 				err(EXIT_FAILURE, "%s", log->logfile);
571 	} else {
572 		snprintf(file1, sizeof(file1), "%s.0", log->logfile);
573 		PRINFO(("mv %s %s\n", log->logfile, file1));
574 		if (!noaction)
575 			if (rename(log->logfile, file1))
576 				err(EXIT_FAILURE, "%s", log->logfile);
577 	}
578 
579 	PRINFO(("(create new log)\n"));
580 	log_create(log);
581 	log_trimmed(log);
582 
583 	/* Set the correct permissions on the log. */
584 	PRINFO(("chmod %o %s\n", log->mode, log->logfile));
585 	if (!noaction)
586 		if (chmod(log->logfile, log->mode))
587 			err(EXIT_FAILURE, "%s", log->logfile);
588 
589 	/* Do we need to signal a daemon? */
590 	if ((log->flags & CE_NOSIGNAL) == 0) {
591 		if (log->pidfile[0] != '\0')
592 			pid = readpidfile(log->pidfile);
593 		else
594 			pid = readpidfile(_PATH_SYSLOGDPID);
595 
596 		if (pid != (pid_t)-1) {
597 			PRINFO(("kill -%s %lu\n",
598 			    sys_signame[log->signum], (u_long)pid));
599 			if (!noaction)
600 				if (kill(pid, log->signum))
601 					warn("kill");
602 		}
603 	}
604 
605 	/* If the newest historical log is to be compressed, do it here. */
606 	if ((log->flags & (CE_PLAIN0 | CE_COMPRESS)) == CE_COMPRESS
607 	    && log->numhist != 0) {
608 		snprintf(file1, sizeof(file1), "%s.0", log->logfile);
609 		if ((log->flags & CE_NOSIGNAL) == 0) {
610 			PRINFO(("sleep for 10 seconds before compressing...\n"));
611 			sleep(10);
612 		}
613 		log_compress(log, file1);
614 	}
615 }
616 
617 /*
618  * Write an entry to the log file recording the fact that it was trimmed.
619  */
620 void
621 log_trimmed(struct conf_entry *log)
622 {
623 	FILE *fd;
624 	time_t now;
625 	char *daytime;
626 
627 	if ((log->flags & CE_BINARY) != 0)
628 		return;
629 	PRINFO(("(append rotation notice to %s)\n", log->logfile));
630 	if (noaction)
631 		return;
632 
633 	if ((fd = fopen(log->logfile, "at")) == NULL)
634 		err(EXIT_FAILURE, "%s", log->logfile);
635 
636 	now = time(NULL);
637 	daytime = ctime(&now) + 4;
638 	daytime[15] = '\0';
639 
640 	fprintf(fd, "%s %s newsyslog[%lu]: log file turned over\n", daytime,
641 	    hostname, (u_long)getpid());
642 	fclose(fd);
643 }
644 
645 /*
646  * Create a new log file.
647  */
648 void
649 log_create(struct conf_entry *log)
650 {
651 	int fd;
652 
653 	if (noaction)
654 		return;
655 
656 	if ((fd = creat(log->logfile, log->mode)) < 0)
657 		err(EXIT_FAILURE, "%s", log->logfile);
658 	if (fchown(fd, log->uid, log->gid) < 0)
659 		err(EXIT_FAILURE, "%s", log->logfile);
660 	close(fd);
661 }
662 
663 /*
664  * Fork off gzip(1) to compress a log file.  This routine takes an
665  * additional string argument (the name of the file to compress): it is also
666  * used to compress historical log files other than the newest.
667  */
668 void
669 log_compress(struct conf_entry *log, const char *fn)
670 {
671 	char tmp[MAXPATHLEN];
672 
673 	PRINFO(("gzip %s\n", fn));
674 	if (!noaction) {
675 		pid_t pid;
676 		int status;
677 
678 		if ((pid = vfork()) < 0)
679 			err(EXIT_FAILURE, "vfork");
680 		else if (pid == 0) {
681 			execl(_PATH_GZIP, "gzip", "-f", fn, NULL);
682 			_exit(EXIT_FAILURE);
683 		}
684 		while (waitpid(pid, &status, 0) != pid);
685 
686 		if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
687 			errx(EXIT_FAILURE, "gzip failed");
688 	}
689 
690 	snprintf(tmp, sizeof(tmp), "%s.gz", fn);
691 	PRINFO(("chown %d:%d %s\n", log->uid, log->gid, tmp));
692 	if (!noaction)
693 		if (chown(tmp, log->uid, log->gid))
694 			err(EXIT_FAILURE, "%s", tmp);
695 }
696 
697 /*
698  * Display program usage information.
699  */
700 void
701 usage(void)
702 {
703 
704 	fprintf(stderr,
705 	    "usage: newsyslog [-nrsvF] [-f config-file] [file ...]\n");
706 	exit(EXIT_FAILURE);
707 }
708 
709 /*
710  * Return non-zero if a string represents a decimal value.
711  */
712 int
713 isnumber(const char *string)
714 {
715 
716 	while (isdigit(*string))
717 		string++;
718 
719 	return (*string == '\0');
720 }
721 
722 /*
723  * Given a signal name, attempt to find the corresponding signal number.
724  */
725 int
726 getsig(const char *sig)
727 {
728 	char *p;
729 	int n;
730 
731 	if (isnumber(sig)) {
732 		n = (int)strtol(sig, &p, 0);
733 		if (p != '\0' || n < 0 || n >= NSIG)
734 			return (-1);
735 		return (n);
736 	}
737 
738 	if (strncasecmp(sig, "SIG", 3) == 0)
739 		sig += 3;
740 	for (n = 1; n < NSIG; n++)
741 		if (strcasecmp(sys_signame[n], sig) == 0)
742 			return (n);
743 	return (-1);
744 }
745 
746 /*
747  * Given a path to a PID file, return the PID contained within.
748  */
749 pid_t
750 readpidfile(const char *file)
751 {
752 	FILE *fd;
753 	char line[BUFSIZ];
754 	pid_t pid;
755 
756 #ifdef notyet
757 	if (file[0] != '/')
758 		snprintf(tmp, sizeof(tmp), "%s%s", _PATH_VARRUN, file);
759 	else
760 		strlcpy(tmp, file, sizeof(tmp));
761 #endif
762 
763 	if ((fd = fopen(file, "rt")) == NULL) {
764 		warn("%s", file);
765 		return (-1);
766 	}
767 
768 	if (fgets(line, sizeof(line) - 1, fd) != NULL) {
769 		line[sizeof(line) - 1] = '\0';
770 		pid = (pid_t)strtol(line, NULL, 0);
771 	} else {
772 		warnx("unable to read %s", file);
773 		pid = (pid_t)-1;
774 	}
775 
776 	fclose(fd);
777 	return (pid);
778 }
779 
780 /*
781  * Parse a user:group specification.
782  *
783  * XXX This is over the top for newsyslog(8).  It should be moved to libutil.
784  */
785 int
786 parse_userspec(const char *name, struct passwd **pw, struct group **gr)
787 {
788 	char buf[MAXLOGNAME * 2 + 2], *group;
789 
790 	strlcpy(buf, name, sizeof(buf));
791 	*gr = NULL;
792 
793 	/*
794 	 * Before attempting to use '.' as a separator, see if the whole
795 	 * string resolves as a user name.
796 	 */
797 	if ((*pw = getpwnam(buf)) != NULL) {
798 		*gr = getgrgid((*pw)->pw_gid);
799 		return (0);
800 	}
801 
802 	/* Split the user and group name. */
803 	if ((group = strchr(buf, ':')) != NULL ||
804 	    (group = strchr(buf, '.')) != NULL)
805 		*group++ = '\0';
806 
807 	if (isnumber(buf))
808 		*pw = getpwuid((uid_t)atoi(buf));
809 	else
810 		*pw = getpwnam(buf);
811 
812 	/*
813 	 * Find the group.  If a group wasn't specified, use the user's
814 	 * `natural' group.  We get to this point even if no user was found.
815 	 * This is to allow the caller to get a better idea of what went
816 	 * wrong, if anything.
817 	 */
818 	if (group == NULL || *group == '\0') {
819 		if (*pw == NULL)
820 			return (-1);
821 		*gr = getgrgid((*pw)->pw_gid);
822 	} else if (isnumber(group))
823 		*gr = getgrgid((gid_t)atoi(group));
824 	else
825 		*gr = getgrnam(group);
826 
827 	return (*pw != NULL && *gr != NULL ? 0 : -1);
828 }
829 
830 /*
831  * Parse a cyclic time specification, the format is as follows:
832  *
833  *	[Dhh] or [Wd[Dhh]] or [Mdd[Dhh]]
834  *
835  * to rotate a log file cyclic at
836  *
837  *	- every day (D) within a specific hour (hh)	(hh = 0...23)
838  *	- once a week (W) at a specific day (d)     OR	(d = 0..6, 0 = Sunday)
839  *	- once a month (M) at a specific day (d)	(d = 1..31,l|L)
840  *
841  * We don't accept a timezone specification; missing fields are defaulted to
842  * the current date but time zero.
843  */
844 time_t
845 parse_dwm(char *s)
846 {
847 	char *t;
848 	struct tm tm, *tmp;
849 	u_long ul;
850 	time_t now;
851 	static int mtab[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
852 	int wmseen, dseen, nd, save;
853 
854 	wmseen = 0;
855 	dseen = 0;
856 
857 	now = time(NULL);
858 	tmp = localtime(&now);
859 	tm = *tmp;
860 
861 	/* Set no. of days per month */
862 	nd = mtab[tm.tm_mon];
863 
864 	if (tm.tm_mon == 1 &&
865 	    ((tm.tm_year + 1900) % 4 == 0) &&
866 	    ((tm.tm_year + 1900) % 100 != 0) &&
867 	    ((tm.tm_year + 1900) % 400 == 0))
868 		nd++;	/* leap year, 29 days in february */
869 	tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
870 
871 	for (;;) {
872 		switch (*s) {
873 		case 'D':
874 			if (dseen)
875 				return ((time_t)-1);
876 			dseen++;
877 			s++;
878 			ul = strtoul(s, &t, 10);
879 			if (ul < 0 || ul > 23)
880 				return ((time_t)-1);
881 			tm.tm_hour = ul;
882 			break;
883 
884 		case 'W':
885 			if (wmseen)
886 				return (-1);
887 			wmseen++;
888 			s++;
889 			ul = strtoul(s, &t, 10);
890 			if (ul < 0 || ul > 6)
891 				return (-1);
892 			if (ul != tm.tm_wday) {
893 				if (ul < tm.tm_wday) {
894 					save = 6 - tm.tm_wday;
895 					save += (ul + 1);
896 				} else
897 					save = ul - tm.tm_wday;
898 				tm.tm_mday += save;
899 
900 				if (tm.tm_mday > nd) {
901 					tm.tm_mon++;
902 					tm.tm_mday = tm.tm_mday - nd;
903 				}
904 			}
905 			break;
906 
907 		case 'M':
908 			if (wmseen)
909 				return (-1);
910 			wmseen++;
911 			s++;
912 			if (tolower(*s) == 'l') {
913 				tm.tm_mday = nd;
914 				s++;
915 				t = s;
916 			} else {
917 				ul = strtoul(s, &t, 10);
918 				if (ul < 1 || ul > 31)
919 					return (-1);
920 
921 				if (ul > nd)
922 					return (-1);
923 				tm.tm_mday = ul;
924 			}
925 			break;
926 
927 		default:
928 			return (-1);
929 			break;
930 		}
931 
932 		if (*t == '\0' || isspace(*t))
933 			break;
934 		else
935 			s = t;
936 	}
937 
938 	return (mktime(&tm));
939 }
940 
941 /*
942  * Parse a limited subset of ISO 8601.  The specific format is as follows:
943  *
944  * [CC[YY[MM[DD]]]][THH[MM[SS]]]	(where `T' is the literal letter)
945  *
946  * We don't accept a timezone specification; missing fields (including
947  * timezone) are defaulted to the current date but time zero.
948  */
949 time_t
950 parse_iso8601(char *s)
951 {
952 	char *t;
953 	struct tm tm, *tmp;
954 	u_long ul;
955 	time_t now;
956 
957 	now = time(NULL);
958 	tmp = localtime(&now);
959 	tm = *tmp;
960 
961 	tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
962 
963 	ul = strtoul(s, &t, 10);
964 	if (*t != '\0' && *t != 'T')
965 		return ((time_t)-1);
966 
967 	/*
968 	 * Now t points either to the end of the string (if no time was
969 	 * provided) or to the letter `T' which separates date and time in
970 	 * ISO 8601.  The pointer arithmetic is the same for either case.
971 	 */
972 	switch (t - s) {
973 	case 8:
974 		tm.tm_year = ((ul / 1000000) - 19) * 100;
975 		ul = ul % 1000000;
976 		/* FALLTHROUGH */
977 	case 6:
978 		tm.tm_year = tm.tm_year - (tm.tm_year % 100);
979 		tm.tm_year += ul / 10000;
980 		ul = ul % 10000;
981 		/* FALLTHROUGH */
982 	case 4:
983 		tm.tm_mon = (ul / 100) - 1;
984 		ul = ul % 100;
985 		/* FALLTHROUGH */
986 	case 2:
987 		tm.tm_mday = ul;
988 		/* FALLTHROUGH */
989 	case 0:
990 		break;
991 	default:
992 		return ((time_t)-1);
993 	}
994 
995 	/* Sanity check */
996 	if (tm.tm_year < 70 || tm.tm_mon < 0 || tm.tm_mon > 12 ||
997 	    tm.tm_mday < 1 || tm.tm_mday > 31)
998 		return ((time_t)-1);
999 
1000 	if (*t != '\0') {
1001 		s = ++t;
1002 		ul = strtoul(s, &t, 10);
1003 		if (*t != '\0' && !isspace(*t))
1004 			return ((time_t)-1);
1005 
1006 		switch (t - s) {
1007 		case 6:
1008 			tm.tm_sec = ul % 100;
1009 			ul /= 100;
1010 			/* FALLTHROUGH */
1011 		case 4:
1012 			tm.tm_min = ul % 100;
1013 			ul /= 100;
1014 			/* FALLTHROUGH */
1015 		case 2:
1016 			tm.tm_hour = ul;
1017 			/* FALLTHROUGH */
1018 		case 0:
1019 			break;
1020 		default:
1021 			return ((time_t)-1);
1022 		}
1023 
1024 		/* Sanity check */
1025 		if (tm.tm_sec < 0 || tm.tm_sec > 60 || tm.tm_min < 0 ||
1026 		    tm.tm_min > 59 || tm.tm_hour < 0 || tm.tm_hour > 23)
1027 			return ((time_t)-1);
1028 	}
1029 
1030 	return (mktime(&tm));
1031 }
1032