xref: /titanic_41/usr/src/cmd/fs.d/nfs/nfslog/nfslogd.c (revision d5ace9454616652a717c9831d949dffa319381f9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1999-2000 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * Postprocessor for NFS server logging.
31  */
32 #include <arpa/inet.h>
33 #include <assert.h>
34 #include <deflt.h>
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <netinet/in.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <strings.h>
42 #include <signal.h>
43 #include <syslog.h>
44 #include <limits.h>
45 #include <libintl.h>
46 #include <locale.h>
47 #include <unistd.h>
48 #include <sys/types.h>
49 #include <sys/utsname.h>
50 #include <sys/stat.h>
51 #include <sys/resource.h>
52 #include <rpc/clnt_stat.h>
53 #include <nfs/nfs.h>
54 #include <nfs/export.h>
55 #include <nfs/nfs_log.h>
56 #include "fhtab.h"
57 #include "nfslogd.h"
58 #include "buffer_list.h"
59 #include "../lib/nfslog_config.h"
60 #include "../lib/nfslogtab.h"
61 
62 enum pidfile_operation {
63 	PID_STARTUP, PID_SHUTDOWN
64 };
65 
66 static int nfslogtab_deactivate_after_boot(void);
67 static int
68 	nfslogtab_remove(struct buffer_ent **, struct buffer_ent **, boolean_t);
69 static int cycle_logs(nfsl_config_t *, int);
70 static void enable_logcycling(void);
71 static int process_pidfile(enum pidfile_operation);
72 static void short_cleanup(void);
73 static void full_cleanup(void);
74 static void transactions_timeout(nfsl_config_t *);
75 static void close_all_translogs(nfsl_config_t *);
76 int cycle_log(char *, int);
77 static boolean_t is_cycle_needed(char *, void **, boolean_t, int *);
78 
79 /*
80  * Configuration information.
81  */
82 
83 int debug = 0;
84 boolean_t test = B_FALSE;
85 time_t mapping_update_interval = MAPPING_UPDATE_INTERVAL;
86 /* prune_timeout measures how old a database entry must be to be pruned */
87 time_t prune_timeout = (SECSPERHOUR * 7 * 24);
88 int max_logs_preserve = MAX_LOGS_PRESERVE;
89 uint_t idle_time = IDLE_TIME;
90 static mode_t Umask = NFSLOG_UMASK;
91 static long cycle_frequency = CYCLE_FREQUENCY;
92 /* prune_frequency measures how often should prune_dbs be called */
93 static long prune_frequency = (SECSPERHOUR * 24);
94 static int min_size = MIN_PROCESSING_SIZE;
95 static volatile bool_t need2cycle = FALSE;
96 static volatile bool_t need2prune = FALSE;
97 boolean_t keep_running = B_TRUE;
98 boolean_t quick_cleaning = B_FALSE;
99 
100 /*ARGSUSED*/
101 int
102 main(int argc, char **argv)
103 {
104 	struct rlimit rl;
105 	int error = 0;
106 	char *defp;
107 	pid_t pid;
108 
109 	timestruc_t logtab_update;
110 	time_t process_start, last_prune = time(0);
111 	time_t last_cycle = time(0);	/* last time logs were cycled */
112 	int processed, buffers_processed;
113 	struct buffer_ent *buffer_list = NULL, *bep, *next;
114 	nfsl_config_t *config_list = NULL;
115 	char	*fhtable_to_prune = NULL;
116 
117 	/*
118 	 * Check to make sure user is root.
119 	 */
120 	if (geteuid() != 0) {
121 		(void) fprintf(stderr, gettext("%s must be run as root\n"),
122 			argv[0]);
123 		exit(1);
124 	}
125 
126 	/*
127 	 * Read defaults file.
128 	 */
129 	if (defopen(NFSLOG_OPTIONS_FILE) == 0) {
130 		if ((defp = defread("DEBUG=")) != NULL) {
131 			debug = atoi(defp);
132 			if (debug > 0)
133 				(void) printf("debug=%d\n", debug);
134 		}
135 		if ((defp = defread("TEST=")) != NULL) {
136 			if (strcmp(defp, "TRUE") == 0)
137 				test = B_TRUE;
138 			if (debug > 0) {
139 				if (test)
140 					(void) printf("test=TRUE\n");
141 				else
142 					(void) printf("test=FALSE\n");
143 			}
144 		}
145 		/*
146 		 * Set Umask for log and fhtable creation.
147 		 */
148 		if ((defp = defread("UMASK=")) != NULL) {
149 			if (sscanf(defp, "%lo", &Umask) != 1)
150 				Umask = NFSLOG_UMASK;
151 		}
152 		/*
153 		 * Minimum size buffer should reach before processing.
154 		 */
155 		if ((defp = defread("MIN_PROCESSING_SIZE=")) != NULL) {
156 			min_size = atoi(defp);
157 			if (debug > 0)
158 				(void) printf("min_size=%d\n", min_size);
159 		}
160 		/*
161 		 * Number of seconds the daemon should
162 		 * sleep waiting for more work.
163 		 */
164 		if ((defp = defread("IDLE_TIME=")) != NULL) {
165 			idle_time = (uint_t)atoi(defp);
166 			if (debug > 0)
167 				(void) printf("idle_time=%d\n", idle_time);
168 		}
169 		/*
170 		 * Maximum number of logs to preserve.
171 		 */
172 		if ((defp = defread("MAX_LOGS_PRESERVE=")) != NULL) {
173 			max_logs_preserve = atoi(defp);
174 			if (debug > 0) {
175 				(void) printf("max_logs_preserve=%d\n",
176 					max_logs_preserve);
177 			}
178 		}
179 		/*
180 		 * Frequency of atime updates.
181 		 */
182 		if ((defp = defread("MAPPING_UPDATE_INTERVAL=")) != NULL) {
183 			mapping_update_interval = atoi(defp);
184 			if (debug > 0) {
185 				(void) printf("mapping_update_interval=%ld\n",
186 					mapping_update_interval);
187 			}
188 		}
189 		/*
190 		 * Time to remove entries
191 		 */
192 		if ((defp = defread("PRUNE_TIMEOUT=")) != NULL) {
193 			/*
194 			 * Prune timeout is in hours but we want
195 			 * deal with the time in seconds internally.
196 			 */
197 			prune_timeout = atoi(defp);
198 			prune_timeout *= SECSPERHOUR;
199 			if (prune_timeout < prune_frequency)
200 				prune_frequency = prune_timeout;
201 			if (debug > 0) {
202 				(void) printf("prune_timeout=%ld\n",
203 					prune_timeout);
204 			}
205 		}
206 		/*
207 		 * fhtable to prune when start (for debug/test purposes)
208 		 */
209 		if ((defp = defread("PRUNE_FHTABLE=")) != NULL) {
210 			/*
211 			 * Specify full pathname of fhtable to prune before
212 			 * any processing is to be done
213 			 */
214 			if (fhtable_to_prune = malloc(strlen(defp) + 1)) {
215 				(void) strcpy(fhtable_to_prune, defp);
216 				if (debug > 0) {
217 					(void) printf("fhtable to prune=%s\n",
218 							fhtable_to_prune);
219 				}
220 			} else {
221 				syslog(LOG_ERR, gettext(
222 					"malloc fhtable_to_prune error %s\n"),
223 					strerror(errno));
224 			}
225 		}
226 		/*
227 		 * Log cycle frequency.
228 		 */
229 		if ((defp = defread("CYCLE_FREQUENCY=")) != NULL) {
230 			cycle_frequency = atol(defp);
231 			if (debug > 0) {
232 				(void) printf("cycle_frequency=%ld\n",
233 					cycle_frequency);
234 			}
235 		}
236 		/*
237 		 * defopen of NULL closes the open defaults file.
238 		 */
239 		(void) defopen((char *)NULL);
240 	}
241 
242 	if (Umask > ((mode_t)0777))
243 		Umask = NFSLOG_UMASK;
244 	(void) umask(Umask);
245 
246 	if (getrlimit(RLIMIT_FSIZE, &rl) < 0) {
247 		error = errno;
248 		(void) fprintf(stderr, gettext(
249 			"getrlimit failed error is %d - %s\n"),
250 			error, strerror(error));
251 		exit(1);
252 	}
253 	if (min_size < 0 || min_size > rl.rlim_cur) {
254 		(void) fprintf(stderr, gettext(
255 			"MIN_PROCESSING_SIZE out of range, should be >= 0 and "
256 			"< %d. Check %s.\n"), rl.rlim_cur, NFSLOG_OPTIONS_FILE);
257 		exit(1);
258 	}
259 	if (idle_time > INT_MAX) {
260 		(void) fprintf(stderr, gettext(
261 			"IDLE_TIME out of range, should be >= 0 and "
262 			"< %d. Check %s.\n"), INT_MAX, NFSLOG_OPTIONS_FILE);
263 		exit(1);
264 	}
265 	if (max_logs_preserve < 0 || max_logs_preserve > INT_MAX) {
266 		(void) fprintf(stderr, gettext(
267 			"MAX_LOGS_PRESERVE out of range, should be >= 0 and "
268 			"< %d. Check %s.\n"), INT_MAX, NFSLOG_OPTIONS_FILE);
269 		exit(1);
270 	}
271 	if (mapping_update_interval < 0|| mapping_update_interval > INT_MAX) {
272 		(void) fprintf(stderr, gettext(
273 			"MAPPING_UPDATE_INTERVAL out of range, "
274 			"should be >= 0 and "
275 			"< %d. Check %s.\n"), INT_MAX, NFSLOG_OPTIONS_FILE);
276 		exit(1);
277 	}
278 	if (cycle_frequency < 0 || cycle_frequency > INT_MAX) {
279 		(void) fprintf(stderr, gettext(
280 			"CYCLE_FREQUENCY out of range, should be >= 0 and "
281 			"< %d. Check %s.\n"), INT_MAX, NFSLOG_OPTIONS_FILE);
282 		exit(1);
283 	}
284 	/* get value in seconds */
285 	cycle_frequency = cycle_frequency * 60 * 60;
286 
287 	/*
288 	 * If we dump core, it will be /core
289 	 */
290 	if (chdir("/") < 0)
291 		(void) fprintf(stderr, gettext("chdir /: %s"), strerror(errno));
292 
293 	/*
294 	 * Config errors to stderr
295 	 */
296 	nfsl_errs_to_syslog = B_FALSE;
297 
298 #ifndef DEBUG
299 	pid = fork();
300 	if (pid == -1) {
301 		(void) fprintf(stderr, gettext("%s: fork failure\n"),
302 			argv[0]);
303 		exit(1);
304 	}
305 	if (pid != 0)
306 		exit(0);
307 	/*
308 	 * Config errors to syslog
309 	 */
310 	nfsl_errs_to_syslog = B_TRUE;
311 #endif /* DEBUG */
312 
313 	(void) setlocale(LC_ALL, "");
314 #if !defined(TEXT_DOMAIN)
315 #define	TEXT_DOMAIN	"SYS_TEST"
316 #endif
317 	(void) textdomain(TEXT_DOMAIN);
318 
319 	/*
320 	 * Check to see if nfslogd is already running.
321 	 */
322 	if (process_pidfile(PID_STARTUP) != 0) {
323 		exit(1);
324 	}
325 
326 	(void) sigset(SIGUSR1, (void (*)(int))enable_logcycling);
327 	(void) sigset(SIGHUP, (void (*)(int))full_cleanup);
328 	(void) sigset(SIGTERM, (void(*)(int))short_cleanup);
329 
330 #ifndef DEBUG
331 	/*
332 	 * Close existing file descriptors, open "/dev/null" as
333 	 * standard input, output, and error, and detach from
334 	 * controlling terminal.
335 	 */
336 	if (!debug && !test) {
337 		closefrom(0);
338 		(void) open("/dev/null", O_RDONLY);
339 		(void) open("/dev/null", O_WRONLY);
340 		(void) dup(1);
341 	}
342 	(void) setsid();
343 #endif /* DEBUG */
344 
345 	openlog(argv[0], LOG_PID, LOG_DAEMON);
346 
347 	public_fh.fh_len = NFS_FHMAXDATA;
348 	public_fh.fh_xlen = NFS_FHMAXDATA;
349 
350 	/*
351 	 * Call once at startup to handle the nfslogtab
352 	 */
353 	if (nfslogtab_deactivate_after_boot() == -1)
354 		exit(1);
355 
356 	/*
357 	 * Get a list of buffers that need to be processed.
358 	 */
359 	if (error = getbuffer_list(&buffer_list, &logtab_update)) {
360 		syslog(LOG_ERR, gettext("Could not read %s: %s"),
361 			NFSLOGTAB, strerror(error));
362 		goto done;
363 	}
364 
365 	/*
366 	 * Get the configuration list.
367 	 */
368 	if (error = nfsl_getconfig_list(&config_list)) {
369 		syslog(LOG_ERR, gettext(
370 			"Could not obtain configuration list: %s"),
371 			strerror(error));
372 		goto done;
373 	}
374 
375 	/*
376 	 * loop to process the work being generated by the NFS server
377 	 */
378 	while (keep_running) {
379 		buffers_processed = 0;
380 		(void) checkbuffer_list(&buffer_list, &logtab_update);
381 
382 		while (buffer_list == NULL) {
383 			/*
384 			 * Nothing to do
385 			 */
386 			(void) sleep(idle_time);
387 
388 			if (!keep_running) {
389 				/*
390 				 * We have been interrupted and asked to
391 				 * flush our transactions and exit.
392 				 */
393 				close_all_translogs(config_list);
394 				goto done;
395 			}
396 			(void) checkbuffer_list(&buffer_list, &logtab_update);
397 		}
398 
399 		process_start = time(0);
400 
401 		if (error = nfsl_checkconfig_list(&config_list, NULL)) {
402 			syslog(LOG_ERR, gettext(
403 				"Could not update configuration list: %s"),
404 				strerror(error));
405 			nfsl_freeconfig_list(&config_list);
406 			goto done;
407 		}
408 
409 		if (difftime(time(0), last_cycle) > cycle_frequency)
410 			need2cycle = TRUE;
411 		if (need2cycle) {
412 			error = cycle_logs(config_list, max_logs_preserve);
413 			if (error) {
414 				syslog(LOG_WARNING, gettext(
415 				    "One or more logfiles couldn't be cycled, "
416 				    "continuing regular processing"));
417 			}
418 			need2cycle = FALSE;
419 			last_cycle = time(0);
420 		}
421 		if (difftime(time(0), last_prune) > prune_frequency)
422 			need2prune = TRUE;
423 		if (need2prune || fhtable_to_prune) {
424 			error = prune_dbs(fhtable_to_prune);
425 			if (error) {
426 				syslog(LOG_WARNING, gettext(
427 				    "Error in cleaning database files"));
428 			}
429 			need2prune = FALSE;
430 			last_prune = time(0);
431 			/* After the first time, use the normal procedure */
432 			free(fhtable_to_prune);
433 			fhtable_to_prune = NULL;
434 		}
435 
436 		for (bep = buffer_list; bep != NULL; bep = next) {
437 			next = bep->be_next;
438 			processed = 0;
439 			error = process_buffer(bep, &config_list,
440 				min_size, idle_time, &processed);
441 			if (error == 0 && processed) {
442 				if (bep->be_error) {
443 					syslog(LOG_ERR, gettext(
444 						"Buffer file '%s' "
445 						"processed successfully."),
446 						bep->be_name);
447 				}
448 				error =
449 				nfslogtab_remove(&buffer_list, &bep, B_FALSE);
450 			} else if (error == ENOENT) {
451 				syslog(LOG_ERR, gettext("Removed entry"
452 					"\t\"%s\t%s\t%d\" from %s"),
453 					bep->be_name,
454 					bep->be_sharepnt->se_name,
455 					bep->be_sharepnt->se_state,
456 					NFSLOGTAB);
457 				error =
458 				nfslogtab_remove(&buffer_list, &bep, B_TRUE);
459 			} else if (error && error != bep->be_error) {
460 				/*
461 				 * An error different from what we've reported
462 				 * before occured.
463 				 */
464 				syslog(LOG_ERR, gettext(
465 					"Cannot process buffer file '%s' - "
466 					"will retry on every iteration."),
467 					bep->be_name);
468 			}
469 
470 			if (bep != NULL)
471 				bep->be_error = error;
472 			buffers_processed += processed;
473 		}
474 
475 		transactions_timeout(config_list);
476 
477 		if (keep_running) {
478 			uint_t process_time;
479 
480 			/*
481 			 * Sleep idle_time minus however long it took us
482 			 * to process the buffers.
483 			 */
484 			process_time =
485 				(uint_t)(difftime(time(0), process_start));
486 			if (process_time < idle_time)
487 				(void) sleep(idle_time - process_time);
488 		}
489 	}
490 
491 done:
492 	/*
493 	 * Make sure to clean house before we exit
494 	 */
495 	close_all_translogs(config_list);
496 	free_buffer_list(&buffer_list);
497 	nfsl_freeconfig_list(&config_list);
498 
499 	(void) process_pidfile(PID_SHUTDOWN);
500 
501 	return (error);
502 }
503 
504 static void
505 short_cleanup(void)
506 {
507 	if (debug) {
508 		(void) fprintf(stderr,
509 			"SIGTERM received, setting state to terminate...\n");
510 	}
511 	quick_cleaning = B_TRUE;
512 	keep_running = B_FALSE;
513 }
514 
515 static void
516 full_cleanup(void)
517 {
518 	if (debug) {
519 		(void) fprintf(stderr,
520 			"SIGHUP received, setting state to shutdown...\n");
521 	}
522 	quick_cleaning = keep_running = B_FALSE;
523 }
524 
525 /*
526  * Removes nfslogtab entries matching the specified buffer_ent,
527  * if 'inactive_only' is set, then only inactive entries are removed.
528  * The buffer_list and sharepoint list entries are removed appropriately.
529  * Returns 0 on success, error otherwise.
530  */
531 static int
532 nfslogtab_remove(
533 	struct buffer_ent **buffer_list,
534 	struct buffer_ent **bep,
535 	boolean_t allstates)
536 {
537 	FILE *fd;
538 	int error = 0;
539 	struct sharepnt_ent *sep, *next;
540 
541 	fd = fopen(NFSLOGTAB, "r+");
542 	rewind(fd);
543 	if (fd == NULL) {
544 		error = errno;
545 		syslog(LOG_ERR, gettext("%s - %s\n"), NFSLOGTAB,
546 			strerror(error));
547 		return (error);
548 	}
549 
550 	if (lockf(fileno(fd), F_LOCK, 0L) < 0) {
551 		error = errno;
552 		syslog(LOG_ERR, gettext("cannot lock %s - %s\n"), NFSLOGTAB,
553 			strerror(error));
554 		(void) fclose(fd);
555 		return (error);
556 	}
557 
558 	for (sep = (*bep)->be_sharepnt; sep != NULL; sep = next) {
559 		next = sep->se_next;
560 		if (!allstates && sep->se_state == LES_ACTIVE)
561 			continue;
562 		if (error = logtab_rement(fd, (*bep)->be_name, sep->se_name,
563 					NULL, sep->se_state)) {
564 			syslog(LOG_ERR, gettext("cannot update %s\n"),
565 				NFSLOGTAB);
566 			error = EIO;
567 			goto errout;
568 		}
569 		remove_sharepnt_ent(&((*bep)->be_sharepnt), sep);
570 	}
571 
572 	if ((*bep)->be_sharepnt == NULL) {
573 		/*
574 		 * All sharepoints were removed from NFSLOGTAB.
575 		 * Remove this buffer from our list.
576 		 */
577 		remove_buffer_ent(buffer_list, *bep);
578 		*bep = NULL;
579 	}
580 
581 errout: (void) fclose(fd);
582 
583 	return (error);
584 }
585 
586 /*
587  * Deactivates entries if nfslogtab is older than the boot time.
588  */
589 static int
590 nfslogtab_deactivate_after_boot(void)
591 {
592 	FILE *fd;
593 	int error = 0;
594 
595 	fd = fopen(NFSLOGTAB, "r+");
596 	if (fd == NULL) {
597 		error = errno;
598 		if (error != ENOENT) {
599 			syslog(LOG_ERR, gettext("%s: %s\n"), NFSLOGTAB,
600 				strerror(error));
601 			return (-1);
602 		}
603 		return (0);
604 	}
605 
606 	if (lockf(fileno(fd), F_LOCK, 0L) < 0) {
607 		error = errno;
608 		syslog(LOG_ERR, gettext("cannot lock %s: %s\n"),
609 			NFSLOGTAB, strerror(error));
610 		(void) fclose(fd);
611 		return (-1);
612 	}
613 
614 	if (logtab_deactivate_after_boot(fd) == -1) {
615 		syslog(LOG_ERR, gettext(
616 			"Cannot deactivate all entries in %s\n"), NFSLOGTAB);
617 		(void) fclose(fd);
618 		return (-1);
619 	}
620 
621 	(void) fclose(fd);
622 	return (0);
623 }
624 
625 /*
626  * Enables the log file cycling flag.
627  */
628 static void
629 enable_logcycling(void)
630 {
631 	need2cycle = TRUE;
632 }
633 
634 /*
635  * Cycle all log files that have been active since the last cycling.
636  * This means it's not simply listed in the configuration file, but
637  * there's information associated with it.
638  */
639 static int
640 cycle_logs(nfsl_config_t *listp, int max_logs_preserve)
641 {
642 	nfsl_config_t *clp;
643 	void *processed_list = NULL;
644 	int error = 0, total_errors = 0;
645 
646 	for (clp = listp; clp != NULL; clp = clp->nc_next) {
647 		error = 0;
648 
649 		/*
650 		 * Process transpath log.
651 		 */
652 		if (clp->nc_logpath) {
653 			if (is_cycle_needed(clp->nc_logpath, &processed_list,
654 			    B_FALSE, &error)) {
655 				if (clp->nc_transcookie != NULL) {
656 					nfslog_close_transactions(
657 						&clp->nc_transcookie);
658 					assert(clp->nc_transcookie == NULL);
659 				}
660 				error = cycle_log(clp->nc_logpath,
661 					max_logs_preserve);
662 			} else if (error)
663 				goto errout;
664 		}
665 		total_errors += error;
666 
667 		/*
668 		 * Process elfpath log.
669 		 */
670 		if (clp->nc_rpclogpath) {
671 			if (is_cycle_needed(clp->nc_rpclogpath, &processed_list,
672 			    B_FALSE, &error)) {
673 				error = cycle_log(clp->nc_rpclogpath,
674 					max_logs_preserve);
675 			} else if (error)
676 				goto errout;
677 		}
678 		total_errors += error;
679 	}
680 
681 errout:
682 	/*
683 	 * Free the list of processed entries.
684 	 */
685 	(void) is_cycle_needed(NULL, &processed_list, B_TRUE, &error);
686 
687 	return (total_errors);
688 }
689 
690 /*
691  * Returns TRUE if this log has not yet been cycled, FALSE otherwise.
692  * '*head' points to the list of entries that have been processed.
693  * If this is a new entry, it gets inserted at the beginning of the
694  * list, and returns TRUE.
695  *
696  * The list is freed if 'need2free' is set, and returns FALSE.
697  * Sets 'error' on failure, and returns FALSE.
698  */
699 static boolean_t
700 is_cycle_needed(char *path, void **list, boolean_t need2free, int *error)
701 {
702 	struct list {
703 		char *log;
704 		struct list *next;
705 	} *head, *next, *p;
706 
707 	head = (struct list *)(*list);
708 	if (need2free) {
709 		/*
710 		 * Free the list and return
711 		 */
712 		for (p = head; p != NULL; p = next) {
713 			next = p->next;
714 			free(p);
715 		}
716 		head = NULL;
717 		return (B_FALSE);
718 	}
719 
720 	assert(path != NULL);
721 	*error = 0;
722 	for (p = head; p != NULL; p = p->next) {
723 		/*
724 		 * Have we seen this before?
725 		 */
726 		if (strcmp(p->log, path) == 0)
727 			return (B_FALSE);
728 	}
729 
730 	/*
731 	 * Add it to the list
732 	 */
733 	if ((p = (struct list *)malloc(sizeof (*p))) == NULL) {
734 		*error = ENOMEM;
735 		syslog(LOG_ERR, gettext("Cannot allocate memory."));
736 		return (B_FALSE);
737 	}
738 	p->log = path;
739 	p->next = head;
740 	head = p;
741 
742 	return (B_TRUE);
743 }
744 
745 /*
746  * cycle given log file.
747  */
748 int
749 cycle_log(char *filename, int max_logs_preserve)
750 {
751 	int i;
752 	char *file_1;
753 	char *file_2;
754 	int error = 0;
755 	struct stat st;
756 
757 	if (max_logs_preserve == 0)
758 		return (0);
759 
760 	if (stat(filename, &st) == -1) {
761 		if (errno == ENOENT) {
762 			/*
763 			 * Nothing to cycle.
764 			 */
765 			return (0);
766 		}
767 		return (errno);
768 	}
769 	file_1 = (char *)malloc(PATH_MAX);
770 	file_2 = (char *)malloc(PATH_MAX);
771 	for (i = max_logs_preserve - 2; i >= 0; i--) {
772 		(void) sprintf(file_1, "%s.%d", filename, i);
773 		(void) sprintf(file_2, "%s.%d", filename, (i + 1));
774 		if (rename(file_1, file_2) == -1) {
775 			error = errno;
776 			if (error != ENOENT) {
777 				syslog(LOG_ERR, gettext(
778 				    "cycle_log: can not rename %s to %s: %s"),
779 				    file_1, file_2, strerror(error));
780 				goto out;
781 			}
782 		}
783 	}
784 	(void) sprintf(file_1, "%s.0", filename);
785 	if (rename(filename, file_1) == -1) {
786 		error = errno;
787 		if (error != ENOENT) {
788 			syslog(LOG_ERR, gettext(
789 				"cycle_log: can not rename %s to %s: %s"),
790 				filename, file_1, strerror(error));
791 			goto out;
792 		}
793 	}
794 	error = 0;
795 
796 out:	free(file_1);
797 	free(file_2);
798 
799 	return (error);
800 }
801 
802 /*
803  * If operation = PID_STARTUP then checks the nfslogd.pid file, it is opened
804  * if it exists, read and the pid is checked for an active process. If no
805  * active process is found, the pid of this process is written to the file,
806  * and 0 is returned, otherwise non-zero error is returned.
807  *
808  * If operation = PID_SHUTDOWN then removes the nfslogd.pid file and 0 is
809  * returned.
810  */
811 static int
812 process_pidfile(enum pidfile_operation op)
813 {
814 	int fd, read_count;
815 	int error = 0;
816 	pid_t pid, mypid;
817 	char *PidFile = NFSLOGD_PIDFILE;
818 	int open_flags;
819 
820 	if (op == PID_STARTUP)
821 		open_flags = O_RDWR | O_CREAT;
822 	else {
823 		assert(op == PID_SHUTDOWN);
824 		open_flags = O_RDWR;
825 	}
826 
827 	if ((fd = open(PidFile, open_flags, 0600)) < 0) {
828 		error = errno;
829 		if (error == ENOENT && op == PID_SHUTDOWN) {
830 			/*
831 			 * We were going to remove it anyway
832 			 */
833 			error = 0;
834 			goto out;
835 		}
836 		(void) fprintf(stderr, gettext(
837 			"cannot open or create pid file %s\n"), PidFile);
838 		goto out;
839 	}
840 	if (lockf(fd, F_LOCK, 0) < 0) {
841 		error = errno;
842 		(void) fprintf(stderr, gettext(
843 			"Cannot lock %s - %s\n"), PidFile,
844 			strerror(error));
845 		goto out;
846 	}
847 	if ((read_count = read(fd, &pid, sizeof (pid))) < 0) {
848 		error = errno;
849 		(void) fprintf(stderr, gettext(
850 			"Can not read from file %s - %s\n"), PidFile,
851 			strerror(error));
852 	}
853 
854 	mypid = getpid();
855 	if (op == PID_STARTUP) {
856 		if (read_count > 0) {
857 			if (kill(pid, 0) == 0) {
858 				error = EEXIST;
859 				(void) fprintf(stderr, gettext(
860 					"Terminated - nfslogd(%ld) already "
861 					"running.\n"), pid);
862 				goto out;
863 			} else if (errno != ESRCH) {
864 				error = errno;
865 				(void) fprintf(stderr, gettext(
866 					"Unexpected error returned %s\n"),
867 					strerror(error));
868 				goto out;
869 			}
870 		}
871 		pid = mypid;
872 		/*
873 		 * rewind the file to overwrite old pid
874 		 */
875 		(void) lseek(fd, 0, SEEK_SET);
876 		if (write(fd, &mypid, sizeof (mypid)) < 0) {
877 			error = errno;
878 			(void) fprintf(stderr, gettext(
879 				"Cannot update %s: %s\n"),
880 				PidFile, strerror(error));
881 		}
882 	} else {
883 		assert(pid == mypid);
884 		if (unlink(PidFile)) {
885 			error = errno;
886 			syslog(LOG_ERR, gettext("Cannot remove %s: %s"),
887 				strerror(error));
888 		}
889 	}
890 out:
891 	if (fd >= 0)
892 		(void) close(fd);
893 	return (error);
894 }
895 
896 /*
897  * Forces a timeout on all open transactions.
898  */
899 static void
900 transactions_timeout(nfsl_config_t *clp)
901 {
902 	for (; clp != NULL; clp = clp->nc_next) {
903 		if (clp->nc_transcookie != NULL) {
904 			nfslog_process_trans_timeout(
905 			    (struct nfslog_trans_file *)clp->nc_transcookie,
906 			    FALSE);
907 		}
908 	}
909 }
910 
911 /*
912  * Closes all transaction logs causing outstanding transactions
913  * to be flushed to their respective log.
914  */
915 static void
916 close_all_translogs(nfsl_config_t *clp)
917 {
918 	for (; clp != NULL; clp = clp->nc_next) {
919 		if (clp->nc_transcookie != NULL) {
920 			nfslog_close_transactions(&clp->nc_transcookie);
921 			assert(clp->nc_transcookie == NULL);
922 		}
923 	}
924 }
925