Merge branch 't/dia'
[dss.git] / dss.c
1 /*
2 * Copyright (C) 2008-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6 #include <string.h>
7 #include <stdlib.h>
8 #include <stdarg.h>
9 #include <assert.h>
10 #include <errno.h>
11 #include <sys/types.h>
12 #include <signal.h>
13 #include <ctype.h>
14 #include <sys/stat.h>
15 #include <unistd.h>
16 #include <inttypes.h>
17 #include <sys/time.h>
18 #include <time.h>
19 #include <sys/wait.h>
20 #include <fnmatch.h>
21 #include <limits.h>
22
23
24 #include "gcc-compat.h"
25 #include "cmdline.h"
26 #include "log.h"
27 #include "str.h"
28 #include "err.h"
29 #include "file.h"
30 #include "exec.h"
31 #include "daemon.h"
32 #include "sig.h"
33 #include "df.h"
34 #include "tv.h"
35 #include "snap.h"
36 #include "ipc.h"
37
38 /** Command line and config file options. */
39 static struct gengetopt_args_info conf;
40 /** Non-NULL if we log to a file. */
41 static FILE *logfile;
42 /** The read end of the signal pipe */
43 static int signal_pipe;
44 /** Process id of current pre-create-hook/rsync/post-create-hook process. */
45 static pid_t create_pid;
46 /** Whether the pre-create-hook/rsync/post-create-hook is currently stopped. */
47 static int create_process_stopped;
48 /** Process id of current pre-remove/rm/post-remove process. */
49 static pid_t remove_pid;
50 /** When the next snapshot is due. */
51 static int64_t next_snapshot_time;
52 /** When to try to remove something. */
53 static struct timeval next_removal_check;
54 /** Creation time of the snapshot currently being created. */
55 static int64_t current_snapshot_creation_time;
56 /** The snapshot currently being removed. */
57 struct snapshot *snapshot_currently_being_removed;
58 /** Needed by the post-create hook. */
59 static char *path_to_last_complete_snapshot;
60 static char *name_of_reference_snapshot;
61 /** \sa \ref snap.h for details. */
62 enum hook_status snapshot_creation_status;
63 /** \sa \ref snap.h for details. */
64 enum hook_status snapshot_removal_status;
65
66
67 DEFINE_DSS_ERRLIST;
68 static const char *hook_status_description[] = {HOOK_STATUS_ARRAY};
69
70 /* may be called with ds == NULL. */
71 static int disk_space_low(struct disk_space *ds)
72 {
73 struct disk_space ds_struct;
74
75 if (!ds) {
76 int ret = get_disk_space(".", &ds_struct);
77 if (ret < 0)
78 return ret;
79 ds = &ds_struct;
80 }
81 if (conf.min_free_mb_arg)
82 if (ds->free_mb < conf.min_free_mb_arg)
83 return 1;
84 if (conf.min_free_percent_arg)
85 if (ds->percent_free < conf.min_free_percent_arg)
86 return 1;
87 if (conf.min_free_percent_inodes_arg)
88 if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg)
89 return 1;
90 return 0;
91 }
92
93 static void dump_dss_config(const char *msg)
94 {
95 const char dash[] = "-----------------------------";
96 int ret;
97 FILE *log = logfile? logfile : stderr;
98 struct disk_space ds;
99 int64_t now = get_current_time();
100
101 if (conf.loglevel_arg > INFO)
102 return;
103
104 fprintf(log, "%s <%s config> %s\n", dash, msg, dash);
105 fprintf(log, "\n*** disk space ***\n\n");
106 ret = get_disk_space(".", &ds);
107 if (ret >= 0) {
108 DSS_INFO_LOG(("disk space low: %s\n", disk_space_low(&ds)?
109 "yes" : "no"));
110 log_disk_space(&ds);
111 } else
112 DSS_ERROR_LOG(("can not get free disk space: %s\n",
113 dss_strerror(-ret)));
114
115 /* we continue on errors from get_disk_space */
116
117 fprintf(log, "\n*** command line and config file options ***\n\n");
118 cmdline_parser_dump(log, &conf);
119 fprintf(log, "\n*** internal state ***\n\n");
120 fprintf(log,
121 "pid: %d\n"
122 "logile: %s\n"
123 "snapshot_currently_being_removed: %s\n"
124 "path_to_last_complete_snapshot: %s\n"
125 "reference_snapshot: %s\n"
126 "snapshot_creation_status: %s\n"
127 "snapshot_removal_status: %s\n"
128 ,
129 (int) getpid(),
130 logfile? conf.logfile_arg : "stderr",
131 snapshot_currently_being_removed?
132 snapshot_currently_being_removed->name : "(none)",
133 path_to_last_complete_snapshot?
134 path_to_last_complete_snapshot : "(none)",
135 name_of_reference_snapshot?
136 name_of_reference_snapshot : "(none)",
137 hook_status_description[snapshot_creation_status],
138 hook_status_description[snapshot_removal_status]
139 );
140 if (create_pid != 0)
141 fprintf(log,
142 "create_pid: %" PRId32 "\n"
143 "create process is %sstopped\n"
144 ,
145 create_pid,
146 create_process_stopped? "" : "not "
147 );
148 if (remove_pid != 0)
149 fprintf(log, "remove_pid: %" PRId32 "\n", remove_pid);
150 if (next_snapshot_time != 0)
151 fprintf(log, "next snapshot due in %" PRId64 " seconds\n",
152 next_snapshot_time - now);
153 if (current_snapshot_creation_time != 0)
154 fprintf(log, "current_snapshot_creation_time: %"
155 PRId64 " (%" PRId64 " seconds ago)\n",
156 current_snapshot_creation_time,
157 now - current_snapshot_creation_time
158 );
159 if (next_removal_check.tv_sec != 0) {
160 fprintf(log, "next removal check: %llu (%llu seconds ago)\n",
161 (long long unsigned)next_removal_check.tv_sec,
162 now - (long long unsigned)next_removal_check.tv_sec
163 );
164
165 }
166 fprintf(log, "%s </%s config> %s\n", dash, msg, dash);
167 }
168
169 /* a litte cpp magic helps to DRY */
170 #define COMMANDS \
171 COMMAND(ls) \
172 COMMAND(create) \
173 COMMAND(prune) \
174 COMMAND(run) \
175 COMMAND(kill) \
176 COMMAND(reload) \
177
178 #define COMMAND(x) static int com_ ##x(void);
179 COMMANDS
180 #undef COMMAND
181 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
182 static int call_command_handler(void)
183 {
184 COMMANDS
185 DSS_EMERG_LOG(("BUG: did not find command handler\n"));
186 return -E_BUG;
187 }
188 #undef COMMAND
189 #undef COMMANDS
190
191 static int loglevel = -1;
192 static const char *location_file = NULL;
193 static int location_line = -1;
194 static const char *location_func = NULL;
195
196 void dss_log_set_params(int ll, const char *file, int line, const char *func)
197 {
198 loglevel = ll;
199 location_file = file;
200 location_line = line;
201 location_func = func;
202 }
203
204 /**
205 * The log function of dss.
206 *
207 * \param ll Loglevel.
208 * \param fml Usual format string.
209 *
210 * All DSS_XXX_LOG() macros use this function.
211 */
212 __printf_1_2 void dss_log(const char* fmt,...)
213 {
214 va_list argp;
215 FILE *outfd;
216 struct tm *tm;
217 time_t t1;
218 char str[255] = "";
219
220 if (loglevel < conf.loglevel_arg)
221 return;
222 outfd = logfile? logfile : stderr;
223 time(&t1);
224 tm = localtime(&t1);
225 strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
226 fprintf(outfd, "%s ", str);
227 if (conf.loglevel_arg <= INFO)
228 fprintf(outfd, "%i: ", loglevel);
229 #ifdef DSS_NO_FUNC_NAMES
230 fprintf(outfd, "%s:%d: ", location_file, location_line);
231 #else
232 fprintf(outfd, "%s: ", location_func);
233 #endif
234 va_start(argp, fmt);
235 vfprintf(outfd, fmt, argp);
236 va_end(argp);
237 }
238
239 /**
240 * Print a message either to stdout or to the log file.
241 */
242 static __printf_1_2 void dss_msg(const char* fmt,...)
243 {
244 FILE *outfd = conf.daemon_given? logfile : stdout;
245 va_list argp;
246 va_start(argp, fmt);
247 vfprintf(outfd, fmt, argp);
248 va_end(argp);
249 }
250
251 static char *get_config_file_name(void)
252 {
253 char *home, *config_file;
254
255 if (conf.config_file_given)
256 return dss_strdup(conf.config_file_arg);
257 home = get_homedir();
258 config_file = make_message("%s/.dssrc", home);
259 free(home);
260 return config_file;
261 }
262
263 static int send_signal(int sig)
264 {
265 pid_t pid;
266 char *config_file = get_config_file_name();
267 int ret = get_dss_pid(config_file, &pid);
268
269 free(config_file);
270 if (ret < 0)
271 return ret;
272 if (conf.dry_run_given) {
273 dss_msg("%d\n", (int)pid);
274 return 0;
275 }
276 ret = kill(pid, sig);
277 if (ret < 0)
278 return -ERRNO_TO_DSS_ERROR(errno);
279 return 1;
280 }
281
282 static int com_kill(void)
283 {
284 return send_signal(SIGTERM);
285 }
286
287 static int com_reload(void)
288 {
289 return send_signal(SIGHUP);
290 }
291
292 static void dss_get_snapshot_list(struct snapshot_list *sl)
293 {
294 get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
295 }
296
297 static int64_t compute_next_snapshot_time(void)
298 {
299 int64_t x = 0, now = get_current_time(), unit_interval
300 = 24 * 3600 * conf.unit_interval_arg, ret;
301 unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
302 num_complete_snapshots = 0;
303 int i;
304 struct snapshot *s = NULL;
305 struct snapshot_list sl;
306
307 dss_get_snapshot_list(&sl);
308 FOR_EACH_SNAPSHOT(s, i, &sl) {
309 if (!(s->flags & SS_COMPLETE))
310 continue;
311 num_complete_snapshots++;
312 x += s->completion_time - s->creation_time;
313 }
314 assert(x >= 0);
315
316 ret = now;
317 if (num_complete_snapshots == 0)
318 goto out;
319 x /= num_complete_snapshots; /* avg time to create one snapshot */
320 if (unit_interval < x * wanted) /* oops, no sleep at all */
321 goto out;
322 ret = s->completion_time + unit_interval / wanted - x;
323 out:
324 free_snapshot_list(&sl);
325 return ret;
326 }
327
328 static inline void invalidate_next_snapshot_time(void)
329 {
330 next_snapshot_time = 0;
331 }
332
333 static inline int next_snapshot_time_is_valid(void)
334 {
335 return next_snapshot_time != 0;
336 }
337
338 static int next_snapshot_is_due(void)
339 {
340 int64_t now = get_current_time();
341
342 if (!next_snapshot_time_is_valid())
343 next_snapshot_time = compute_next_snapshot_time();
344 if (next_snapshot_time <= now) {
345 DSS_DEBUG_LOG(("next snapshot: now\n"));
346 return 1;
347 }
348 DSS_DEBUG_LOG(("next snapshot due in %" PRId64 " seconds\n",
349 next_snapshot_time - now));
350 return 0;
351 }
352
353 static void pre_create_hook(void)
354 {
355 assert(snapshot_creation_status == HS_READY);
356 /* make sure that the next snapshot time will be recomputed */
357 invalidate_next_snapshot_time();
358 DSS_DEBUG_LOG(("executing %s\n", conf.pre_create_hook_arg));
359 dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg);
360 snapshot_creation_status = HS_PRE_RUNNING;
361 }
362
363 static void pre_remove_hook(struct snapshot *s, const char *why)
364 {
365 char *cmd;
366
367 if (!s)
368 return;
369 DSS_DEBUG_LOG(("%s snapshot %s\n", why, s->name));
370 assert(snapshot_removal_status == HS_READY);
371 assert(remove_pid == 0);
372 assert(!snapshot_currently_being_removed);
373
374 snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot));
375 *snapshot_currently_being_removed = *s;
376 snapshot_currently_being_removed->name = dss_strdup(s->name);
377
378 cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
379 conf.dest_dir_arg, s->name);
380 DSS_DEBUG_LOG(("executing %s\n", cmd));
381 dss_exec_cmdline_pid(&remove_pid, cmd);
382 free(cmd);
383 snapshot_removal_status = HS_PRE_RUNNING;
384 }
385
386 static int exec_rm(void)
387 {
388 struct snapshot *s = snapshot_currently_being_removed;
389 char *new_name = being_deleted_name(s);
390 char *argv[4];
391 int ret;
392
393 argv[0] = "rm";
394 argv[1] = "-rf";
395 argv[2] = new_name;
396 argv[3] = NULL;
397
398 assert(snapshot_removal_status == HS_PRE_SUCCESS);
399 assert(remove_pid == 0);
400
401 DSS_NOTICE_LOG(("removing %s (interval = %i)\n", s->name, s->interval));
402 ret = dss_rename(s->name, new_name);
403 if (ret < 0)
404 goto out;
405 dss_exec(&remove_pid, argv[0], argv);
406 snapshot_removal_status = HS_RUNNING;
407 out:
408 free(new_name);
409 return ret;
410 }
411
412 static int snapshot_is_being_created(struct snapshot *s)
413 {
414 return s->creation_time == current_snapshot_creation_time;
415 }
416
417 static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl)
418 {
419 struct snapshot *s;
420 int i;
421
422 DSS_DEBUG_LOG(("looking for orphaned snapshots\n"));
423 FOR_EACH_SNAPSHOT(s, i, sl) {
424 if (snapshot_is_being_created(s))
425 continue;
426 /*
427 * We know that no rm is currently running, so if s is marked
428 * as being deleted, a previously started rm must have failed.
429 */
430 if (s->flags & SS_BEING_DELETED)
431 return s;
432
433 if (s->flags & SS_COMPLETE) /* good snapshot */
434 continue;
435 /*
436 * This snapshot is incomplete and it is not the snapshot
437 * currently being created. However, we must not remove it if
438 * rsync is about to be restarted. As only the newest snapshot
439 * can be restarted, this snapshot is orphaned if it is not the
440 * newest snapshot or if we are not about to restart rsync.
441 */
442 if (get_newest_snapshot(sl) != s)
443 return s;
444 if (snapshot_creation_status != HS_NEEDS_RESTART)
445 return s;
446 }
447 /* no orphaned snapshots */
448 return NULL;
449 }
450
451 static int is_reference_snapshot(struct snapshot *s)
452 {
453 if (!name_of_reference_snapshot)
454 return 0;
455 return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
456 }
457
458 /*
459 * return: 0: no redundant snapshots, 1: rm process started, negative: error
460 */
461 static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
462 {
463 int i, interval;
464 struct snapshot *s;
465 unsigned missing = 0;
466
467 DSS_DEBUG_LOG(("looking for intervals containing too many snapshots\n"));
468 for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
469 unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg);
470 unsigned num = sl->interval_count[interval];
471 struct snapshot *victim = NULL, *prev = NULL;
472 int64_t score = LONG_MAX;
473
474 if (keep >= num)
475 missing += keep - num;
476 if (keep + missing >= num)
477 continue;
478 /* redundant snapshot in this interval, pick snapshot with lowest score */
479 FOR_EACH_SNAPSHOT(s, i, sl) {
480 int64_t this_score;
481
482 if (snapshot_is_being_created(s))
483 continue;
484 if (is_reference_snapshot(s))
485 continue;
486 if (s->interval > interval) {
487 prev = s;
488 continue;
489 }
490 if (s->interval < interval)
491 break;
492 if (!victim) {
493 victim = s;
494 prev = s;
495 continue;
496 }
497 assert(prev);
498 /* check if s is a better victim */
499 this_score = s->creation_time - prev->creation_time;
500 assert(this_score >= 0);
501 if (this_score < score) {
502 score = this_score;
503 victim = s;
504 }
505 prev = s;
506 }
507 assert(victim);
508 return victim;
509 }
510 return NULL;
511 }
512
513 static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl)
514 {
515 int i;
516 struct snapshot *s;
517
518 DSS_DEBUG_LOG(("looking for snapshots belonging to intervals >= %d\n",
519 conf.num_intervals_arg));
520 FOR_EACH_SNAPSHOT(s, i, sl) {
521 if (snapshot_is_being_created(s))
522 continue;
523 if (is_reference_snapshot(s))
524 continue;
525 if (s->interval < conf.num_intervals_arg)
526 continue;
527 return s;
528 }
529 return NULL;
530 }
531
532 static struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
533 {
534 int i;
535 struct snapshot *s;
536 FOR_EACH_SNAPSHOT(s, i, sl) {
537 if (snapshot_is_being_created(s))
538 continue;
539 if (is_reference_snapshot(s))
540 continue;
541 DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name));
542 return s;
543 }
544 return NULL;
545 }
546
547 static int rename_incomplete_snapshot(int64_t start)
548 {
549 char *old_name;
550 int ret;
551 int64_t now;
552
553 /*
554 * We don't want the dss_rename() below to fail with EEXIST because the
555 * last complete snapshot was created (and completed) in the same
556 * second as this one.
557 */
558 while ((now = get_current_time()) == start)
559 sleep(1);
560 free(path_to_last_complete_snapshot);
561 ret = complete_name(start, now, &path_to_last_complete_snapshot);
562 if (ret < 0)
563 return ret;
564 old_name = incomplete_name(start);
565 ret = dss_rename(old_name, path_to_last_complete_snapshot);
566 if (ret >= 0)
567 DSS_NOTICE_LOG(("%s -> %s\n", old_name,
568 path_to_last_complete_snapshot));
569 free(old_name);
570 return ret;
571 }
572
573 static int try_to_free_disk_space(void)
574 {
575 int ret;
576 struct snapshot_list sl;
577 struct snapshot *victim;
578 struct timeval now;
579 const char *why;
580 int low_disk_space;
581
582 ret = disk_space_low(NULL);
583 if (ret < 0)
584 return ret;
585 low_disk_space = ret;
586 gettimeofday(&now, NULL);
587 if (tv_diff(&next_removal_check, &now, NULL) > 0)
588 return 0;
589 if (!low_disk_space) {
590 if (conf.keep_redundant_given)
591 return 0;
592 if (snapshot_creation_status != HS_READY)
593 return 0;
594 if (next_snapshot_is_due())
595 return 0;
596 }
597 dss_get_snapshot_list(&sl);
598 ret = 0;
599 if (!low_disk_space && sl.num_snapshots <= 1)
600 goto out;
601 why = "outdated";
602 victim = find_outdated_snapshot(&sl);
603 if (victim)
604 goto remove;
605 why = "redundant";
606 victim = find_redundant_snapshot(&sl);
607 if (victim)
608 goto remove;
609 /* try harder only if disk space is low */
610 if (!low_disk_space)
611 goto out;
612 why = "orphaned";
613 victim = find_orphaned_snapshot(&sl);
614 if (victim)
615 goto remove;
616 DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n"));
617 victim = find_oldest_removable_snapshot(&sl);
618 if (victim)
619 goto remove;
620 DSS_CRIT_LOG(("uhuhu: disk space low and nothing to remove\n"));
621 ret = -ERRNO_TO_DSS_ERROR(ENOSPC);
622 goto out;
623 remove:
624 pre_remove_hook(victim, why);
625 out:
626 free_snapshot_list(&sl);
627 return ret;
628 }
629
630 static void post_create_hook(void)
631 {
632 char *cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
633 conf.dest_dir_arg, path_to_last_complete_snapshot);
634 DSS_NOTICE_LOG(("executing %s\n", cmd));
635 dss_exec_cmdline_pid(&create_pid, cmd);
636 free(cmd);
637 snapshot_creation_status = HS_POST_RUNNING;
638 }
639
640 static void post_remove_hook(void)
641 {
642 char *cmd;
643 struct snapshot *s = snapshot_currently_being_removed;
644
645 assert(s);
646
647 cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
648 conf.dest_dir_arg, s->name);
649 DSS_NOTICE_LOG(("executing %s\n", cmd));
650 dss_exec_cmdline_pid(&remove_pid, cmd);
651 free(cmd);
652 snapshot_removal_status = HS_POST_RUNNING;
653 }
654
655 static void dss_kill(pid_t pid, int sig, const char *msg)
656 {
657 const char *signame, *process_name;
658
659 if (pid == 0)
660 return;
661 switch (sig) {
662 case SIGTERM: signame = "TERM"; break;
663 case SIGSTOP: signame = "STOP"; break;
664 case SIGCONT: signame = "CONT"; break;
665 default: signame = "????";
666 }
667
668 if (pid == create_pid)
669 process_name = "create";
670 else if (pid == remove_pid)
671 process_name = "remove";
672 else process_name = "??????";
673
674 if (msg)
675 DSS_INFO_LOG(("%s\n", msg));
676 DSS_DEBUG_LOG(("sending signal %d (%s) to pid %d (%s process)\n",
677 sig, signame, (int)pid, process_name));
678 if (kill(pid, sig) >= 0)
679 return;
680 DSS_INFO_LOG(("failed to send signal %d (%s) to pid %d (%s process)\n",
681 sig, signame, (int)pid, process_name));
682 }
683
684 static void stop_create_process(void)
685 {
686 if (create_process_stopped)
687 return;
688 dss_kill(create_pid, SIGSTOP, "suspending create process");
689 create_process_stopped = 1;
690 }
691
692 static void restart_create_process(void)
693 {
694 if (!create_process_stopped)
695 return;
696 dss_kill(create_pid, SIGCONT, "resuming create process");
697 create_process_stopped = 0;
698 }
699
700 /**
701 * Print a log message about the exit status of a child.
702 */
703 static void log_termination_msg(pid_t pid, int status)
704 {
705 if (WIFEXITED(status))
706 DSS_INFO_LOG(("child %i exited. Exit status: %i\n", (int)pid,
707 WEXITSTATUS(status)));
708 else if (WIFSIGNALED(status))
709 DSS_NOTICE_LOG(("child %i was killed by signal %i\n", (int)pid,
710 WTERMSIG(status)));
711 else
712 DSS_WARNING_LOG(("child %i terminated abormally\n", (int)pid));
713 }
714
715 static int wait_for_process(pid_t pid, int *status)
716 {
717 int ret;
718
719 DSS_DEBUG_LOG(("Waiting for process %d to terminate\n", (int)pid));
720 for (;;) {
721 fd_set rfds;
722
723 FD_ZERO(&rfds);
724 FD_SET(signal_pipe, &rfds);
725 ret = dss_select(signal_pipe + 1, &rfds, NULL, NULL);
726 if (ret < 0)
727 break;
728 ret = next_signal();
729 if (!ret)
730 continue;
731 if (ret == SIGCHLD) {
732 ret = waitpid(pid, status, 0);
733 if (ret >= 0)
734 break;
735 if (errno != EINTR) { /* error */
736 ret = -ERRNO_TO_DSS_ERROR(errno);
737 break;
738 }
739 }
740 /* SIGINT or SIGTERM */
741 dss_kill(pid, SIGTERM, "killing child process");
742 }
743 if (ret < 0)
744 DSS_ERROR_LOG(("failed to wait for process %d\n", (int)pid));
745 else
746 log_termination_msg(pid, *status);
747 return ret;
748 }
749
750 static void handle_pre_remove_exit(int status)
751 {
752 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
753 snapshot_removal_status = HS_READY;
754 gettimeofday(&next_removal_check, NULL);
755 next_removal_check.tv_sec += 60;
756 return;
757 }
758 snapshot_removal_status = HS_PRE_SUCCESS;
759 }
760
761 static int handle_rm_exit(int status)
762 {
763 if (!WIFEXITED(status)) {
764 snapshot_removal_status = HS_READY;
765 return -E_INVOLUNTARY_EXIT;
766 }
767 if (WEXITSTATUS(status)) {
768 snapshot_removal_status = HS_READY;
769 return -E_BAD_EXIT_CODE;
770 }
771 snapshot_removal_status = HS_SUCCESS;
772 return 1;
773 }
774
775 static void handle_post_remove_exit(void)
776 {
777 snapshot_removal_status = HS_READY;
778 }
779
780 static int handle_remove_exit(int status)
781 {
782 int ret;
783 struct snapshot *s = snapshot_currently_being_removed;
784
785 assert(s);
786 switch (snapshot_removal_status) {
787 case HS_PRE_RUNNING:
788 handle_pre_remove_exit(status);
789 ret = 1;
790 break;
791 case HS_RUNNING:
792 ret = handle_rm_exit(status);
793 break;
794 case HS_POST_RUNNING:
795 handle_post_remove_exit();
796 ret = 1;
797 break;
798 default:
799 ret = -E_BUG;
800 }
801 if (snapshot_removal_status == HS_READY) {
802 free(s->name);
803 free(s);
804 snapshot_currently_being_removed = NULL;
805 }
806 remove_pid = 0;
807 return ret;
808 }
809
810 static int wait_for_remove_process(void)
811 {
812 int status, ret;
813
814 assert(remove_pid);
815 assert(
816 snapshot_removal_status == HS_PRE_RUNNING ||
817 snapshot_removal_status == HS_RUNNING ||
818 snapshot_removal_status == HS_POST_RUNNING
819 );
820 ret = wait_for_process(remove_pid, &status);
821 if (ret < 0)
822 return ret;
823 return handle_remove_exit(status);
824 }
825
826 static int handle_rsync_exit(int status)
827 {
828 int es, ret;
829
830 if (!WIFEXITED(status)) {
831 DSS_ERROR_LOG(("rsync process %d died involuntary\n", (int)create_pid));
832 ret = -E_INVOLUNTARY_EXIT;
833 snapshot_creation_status = HS_READY;
834 goto out;
835 }
836 es = WEXITSTATUS(status);
837 /*
838 * Restart rsync on non-fatal errors:
839 * 12: Error in rsync protocol data stream
840 * 13: Errors with program diagnostics
841 */
842 if (es == 12 || es == 13) {
843 DSS_WARNING_LOG(("rsync process %d returned %d -- restarting\n",
844 (int)create_pid, es));
845 snapshot_creation_status = HS_NEEDS_RESTART;
846 next_snapshot_time = get_current_time() + 60;
847 ret = 1;
848 goto out;
849 }
850 if (es != 0 && es != 23 && es != 24) {
851 DSS_ERROR_LOG(("rsync process %d returned %d\n", (int)create_pid, es));
852 ret = -E_BAD_EXIT_CODE;
853 snapshot_creation_status = HS_READY;
854 goto out;
855 }
856 ret = rename_incomplete_snapshot(current_snapshot_creation_time);
857 if (ret < 0)
858 goto out;
859 snapshot_creation_status = HS_SUCCESS;
860 free(name_of_reference_snapshot);
861 name_of_reference_snapshot = NULL;
862 out:
863 create_process_stopped = 0;
864 return ret;
865 }
866
867 static int handle_pre_create_hook_exit(int status)
868 {
869 int es, ret;
870 static int warn_count;
871
872 if (!WIFEXITED(status)) {
873 snapshot_creation_status = HS_READY;
874 ret = -E_INVOLUNTARY_EXIT;
875 goto out;
876 }
877 es = WEXITSTATUS(status);
878 if (es) {
879 if (!warn_count--) {
880 DSS_NOTICE_LOG(("pre_create_hook %s returned %d\n",
881 conf.pre_create_hook_arg, es));
882 DSS_NOTICE_LOG(("deferring snapshot creation...\n"));
883 warn_count = 60; /* warn only once per hour */
884 }
885 next_snapshot_time = get_current_time() + 60;
886 snapshot_creation_status = HS_READY;
887 ret = 0;
888 goto out;
889 }
890 warn_count = 0;
891 snapshot_creation_status = HS_PRE_SUCCESS;
892 ret = 1;
893 out:
894 return ret;
895 }
896
897 static int handle_sigchld(void)
898 {
899 pid_t pid;
900 int status, ret = reap_child(&pid, &status);
901
902 if (ret <= 0)
903 return ret;
904
905 if (pid == create_pid) {
906 switch (snapshot_creation_status) {
907 case HS_PRE_RUNNING:
908 ret = handle_pre_create_hook_exit(status);
909 break;
910 case HS_RUNNING:
911 ret = handle_rsync_exit(status);
912 break;
913 case HS_POST_RUNNING:
914 snapshot_creation_status = HS_READY;
915 ret = 1;
916 break;
917 default:
918 DSS_EMERG_LOG(("BUG: create can't die in status %d\n",
919 snapshot_creation_status));
920 return -E_BUG;
921 }
922 create_pid = 0;
923 return ret;
924 }
925 if (pid == remove_pid) {
926 ret = handle_remove_exit(status);
927 if (ret < 0)
928 return ret;
929 return ret;
930 }
931 DSS_EMERG_LOG(("BUG: unknown process %d died\n", (int)pid));
932 return -E_BUG;
933 }
934
935 static int check_config(void)
936 {
937 if (conf.unit_interval_arg <= 0) {
938 DSS_ERROR_LOG(("bad unit interval: %i\n", conf.unit_interval_arg));
939 return -E_INVALID_NUMBER;
940 }
941 DSS_DEBUG_LOG(("unit interval: %i day(s)\n", conf.unit_interval_arg));
942 if (conf.num_intervals_arg <= 0 || conf.num_intervals_arg > 30) {
943 DSS_ERROR_LOG(("bad number of intervals: %i\n",
944 conf.num_intervals_arg));
945 return -E_INVALID_NUMBER;
946 }
947 DSS_DEBUG_LOG(("number of intervals: %i\n", conf.num_intervals_arg));
948 return 1;
949 }
950
951 /*
952 * Returns < 0 on errors, 0 if no config file is given and > 0 if the config
953 * file was read successfully.
954 */
955 static int parse_config_file(int override)
956 {
957 int ret, config_file_exists;
958 char *config_file = get_config_file_name();
959 struct stat statbuf;
960 char *old_logfile_arg = NULL;
961 int old_daemon_given = 0;
962
963 if (override) { /* SIGHUP */
964 if (conf.logfile_given)
965 old_logfile_arg = dss_strdup(conf.logfile_arg);
966 old_daemon_given = conf.daemon_given;
967 }
968
969 config_file_exists = !stat(config_file, &statbuf);
970 if (!config_file_exists && conf.config_file_given) {
971 ret = -ERRNO_TO_DSS_ERROR(errno);
972 DSS_ERROR_LOG(("failed to stat config file %s\n", config_file));
973 goto out;
974 }
975 if (config_file_exists) {
976 struct cmdline_parser_params params;
977 params.override = override;
978 params.initialize = 0;
979 params.check_required = 1;
980 params.check_ambiguity = 0;
981 params.print_errors = 1;
982 if (override) { /* invalidate all rsync options */
983 int i;
984
985 for (i = 0; i < conf.rsync_option_given; i++) {
986 free(conf.rsync_option_arg[i]);
987 conf.rsync_option_arg[i] = NULL;
988 }
989 conf.rsync_option_given = 0;
990 }
991 cmdline_parser_config_file(config_file, &conf, &params);
992 }
993 ret = check_config();
994 if (ret < 0)
995 goto out;
996 if (override) {
997 /* don't change daemon mode on SIGHUP */
998 conf.daemon_given = old_daemon_given;
999 close_log(logfile);
1000 logfile = NULL;
1001 if (conf.logfile_given)
1002 free(old_logfile_arg);
1003 else if (conf.daemon_given) { /* re-use old logfile */
1004 conf.logfile_arg = old_logfile_arg;
1005 conf.logfile_given = 1;
1006 }
1007 }
1008 if (conf.logfile_given && conf.run_given && conf.daemon_given) {
1009 logfile = open_log(conf.logfile_arg);
1010 log_welcome(conf.loglevel_arg);
1011 }
1012 DSS_DEBUG_LOG(("loglevel: %d\n", conf.loglevel_arg));
1013 ret = config_file_exists;
1014 out:
1015 free(config_file);
1016 if (ret < 0)
1017 DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
1018 return ret;
1019 }
1020
1021 static int change_to_dest_dir(void)
1022 {
1023 DSS_INFO_LOG(("changing cwd to %s\n", conf.dest_dir_arg));
1024 return dss_chdir(conf.dest_dir_arg);
1025 }
1026
1027 static int handle_sighup(void)
1028 {
1029 int ret;
1030
1031 DSS_NOTICE_LOG(("SIGHUP, re-reading config\n"));
1032 dump_dss_config("old");
1033 ret = parse_config_file(1);
1034 if (ret < 0)
1035 return ret;
1036 dump_dss_config("reloaded");
1037 invalidate_next_snapshot_time();
1038 return change_to_dest_dir();
1039 }
1040
1041 static int handle_signal(void)
1042 {
1043 int sig, ret = next_signal();
1044
1045 if (ret <= 0)
1046 goto out;
1047 sig = ret;
1048 switch (sig) {
1049 case SIGINT:
1050 case SIGTERM:
1051 restart_create_process();
1052 dss_kill(create_pid, SIGTERM, NULL);
1053 dss_kill(remove_pid, SIGTERM, NULL);
1054 ret = -E_SIGNAL;
1055 break;
1056 case SIGHUP:
1057 ret = handle_sighup();
1058 break;
1059 case SIGCHLD:
1060 ret = handle_sigchld();
1061 break;
1062 }
1063 out:
1064 if (ret < 0)
1065 DSS_ERROR_LOG(("%s\n", dss_strerror(-ret)));
1066 return ret;
1067 }
1068
1069 /*
1070 * We can not use rsync locally if the local user is different from the remote
1071 * user or if the src dir is not on the local host (or both).
1072 */
1073 static int use_rsync_locally(char *logname)
1074 {
1075 char *h = conf.remote_host_arg;
1076
1077 if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1"))
1078 return 0;
1079 if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname))
1080 return 0;
1081 return 1;
1082 }
1083
1084 static int rename_resume_snap(int64_t creation_time)
1085 {
1086 struct snapshot_list sl;
1087 struct snapshot *s = NULL;
1088 char *new_name = incomplete_name(creation_time);
1089 int ret;
1090 const char *why;
1091
1092 sl.num_snapshots = 0;
1093
1094 ret = 0;
1095 if (conf.no_resume_given)
1096 goto out;
1097 dss_get_snapshot_list(&sl);
1098 /*
1099 * Snapshot recycling: We first look at the newest snapshot. If this
1100 * snapshot happens to be incomplete, the last rsync process was
1101 * aborted and we reuse this one. Otherwise we look at snapshots which
1102 * could be removed (outdated and redundant snapshots) as candidates
1103 * for recycling. If no outdated/redundant snapshot exists, we check if
1104 * there is an orphaned snapshot, which likely is useless anyway.
1105 *
1106 * Only if no existing snapshot is suitable for recycling, we bite the
1107 * bullet and create a new one.
1108 */
1109 s = get_newest_snapshot(&sl);
1110 if (!s) /* no snapshots at all */
1111 goto out;
1112 /* re-use last snapshot if it is incomplete */
1113 why = "aborted";
1114 if ((s->flags & SS_COMPLETE) == 0)
1115 goto out;
1116 why = "outdated";
1117 s = find_outdated_snapshot(&sl);
1118 if (s)
1119 goto out;
1120 why = "redundant";
1121 s = find_redundant_snapshot(&sl);
1122 if (s)
1123 goto out;
1124 why = "orphaned";
1125 s = find_orphaned_snapshot(&sl);
1126 out:
1127 if (s) {
1128 DSS_INFO_LOG(("reusing %s snapshot %s\n", why, s->name));
1129 ret = dss_rename(s->name, new_name);
1130 }
1131 if (ret >= 0)
1132 DSS_NOTICE_LOG(("creating new snapshot %s\n", new_name));
1133 free(new_name);
1134 free_snapshot_list(&sl);
1135 return ret;
1136 }
1137
1138 static void create_rsync_argv(char ***argv, int64_t *num)
1139 {
1140 char *logname;
1141 int i = 0, j;
1142 struct snapshot_list sl;
1143
1144 dss_get_snapshot_list(&sl);
1145 assert(!name_of_reference_snapshot);
1146 name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
1147 free_snapshot_list(&sl);
1148
1149 *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
1150 (*argv)[i++] = dss_strdup("rsync");
1151 (*argv)[i++] = dss_strdup("-a");
1152 (*argv)[i++] = dss_strdup("--delete");
1153 for (j = 0; j < conf.rsync_option_given; j++)
1154 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
1155 if (name_of_reference_snapshot) {
1156 DSS_INFO_LOG(("using %s as reference\n", name_of_reference_snapshot));
1157 (*argv)[i++] = make_message("--link-dest=../%s",
1158 name_of_reference_snapshot);
1159 } else
1160 DSS_INFO_LOG(("no suitable reference snapshot found\n"));
1161 logname = dss_logname();
1162 if (use_rsync_locally(logname))
1163 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
1164 else
1165 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
1166 conf.remote_user_arg : logname,
1167 conf.remote_host_arg, conf.source_dir_arg);
1168 free(logname);
1169 *num = get_current_time();
1170 (*argv)[i++] = incomplete_name(*num);
1171 (*argv)[i++] = NULL;
1172 for (j = 0; j < i; j++)
1173 DSS_DEBUG_LOG(("argv[%d] = %s\n", j, (*argv)[j]));
1174 }
1175
1176 static void free_rsync_argv(char **argv)
1177 {
1178 int i;
1179
1180 if (!argv)
1181 return;
1182 for (i = 0; argv[i]; i++)
1183 free(argv[i]);
1184 free(argv);
1185 }
1186
1187 static int create_snapshot(char **argv)
1188 {
1189 int ret;
1190
1191 ret = rename_resume_snap(current_snapshot_creation_time);
1192 if (ret < 0)
1193 return ret;
1194 dss_exec(&create_pid, argv[0], argv);
1195 snapshot_creation_status = HS_RUNNING;
1196 return ret;
1197 }
1198
1199 static int select_loop(void)
1200 {
1201 int ret;
1202 /* check every 60 seconds for free disk space */
1203 struct timeval tv;
1204 char **rsync_argv = NULL;
1205
1206 for (;;) {
1207 fd_set rfds;
1208 struct timeval *tvp;
1209
1210 if (remove_pid)
1211 tvp = NULL; /* sleep until rm hook/process dies */
1212 else { /* sleep one minute */
1213 tv.tv_sec = 60;
1214 tv.tv_usec = 0;
1215 tvp = &tv;
1216 }
1217 FD_ZERO(&rfds);
1218 FD_SET(signal_pipe, &rfds);
1219 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
1220 if (ret < 0)
1221 goto out;
1222 if (FD_ISSET(signal_pipe, &rfds)) {
1223 ret = handle_signal();
1224 if (ret < 0)
1225 goto out;
1226 }
1227 if (remove_pid)
1228 continue;
1229 if (snapshot_removal_status == HS_PRE_SUCCESS) {
1230 ret = exec_rm();
1231 if (ret < 0)
1232 goto out;
1233 continue;
1234 }
1235 if (snapshot_removal_status == HS_SUCCESS) {
1236 post_remove_hook();
1237 continue;
1238 }
1239 ret = try_to_free_disk_space();
1240 if (ret < 0)
1241 goto out;
1242 if (snapshot_removal_status != HS_READY) {
1243 stop_create_process();
1244 continue;
1245 }
1246 restart_create_process();
1247 switch (snapshot_creation_status) {
1248 case HS_READY:
1249 if (!next_snapshot_is_due())
1250 continue;
1251 pre_create_hook();
1252 continue;
1253 case HS_PRE_RUNNING:
1254 case HS_RUNNING:
1255 case HS_POST_RUNNING:
1256 continue;
1257 case HS_PRE_SUCCESS:
1258 if (!name_of_reference_snapshot) {
1259 free_rsync_argv(rsync_argv);
1260 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1261 }
1262 ret = create_snapshot(rsync_argv);
1263 if (ret < 0)
1264 goto out;
1265 continue;
1266 case HS_NEEDS_RESTART:
1267 if (!next_snapshot_is_due())
1268 continue;
1269 ret = create_snapshot(rsync_argv);
1270 if (ret < 0)
1271 goto out;
1272 continue;
1273 case HS_SUCCESS:
1274 post_create_hook();
1275 continue;
1276 }
1277 }
1278 out:
1279 return ret;
1280 }
1281
1282 static void exit_hook(int exit_code)
1283 {
1284 char *argv[3];
1285 pid_t pid;
1286
1287 argv[0] = conf.exit_hook_arg;
1288 argv[1] = dss_strerror(-exit_code);
1289 argv[2] = NULL;
1290
1291 DSS_NOTICE_LOG(("executing %s %s\n", argv[0], argv[1]));
1292 dss_exec(&pid, conf.exit_hook_arg, argv);
1293 }
1294
1295 static void lock_dss_or_die(void)
1296 {
1297 char *config_file = get_config_file_name();
1298 int ret = lock_dss(config_file);
1299
1300 free(config_file);
1301 if (ret < 0) {
1302 DSS_EMERG_LOG(("failed to lock: %s\n", dss_strerror(-ret)));
1303 exit(EXIT_FAILURE);
1304 }
1305 }
1306
1307 static int com_run(void)
1308 {
1309 int ret;
1310
1311 lock_dss_or_die();
1312 if (conf.dry_run_given) {
1313 DSS_ERROR_LOG(("dry_run not supported by this command\n"));
1314 return -E_SYNTAX;
1315 }
1316 ret = install_sighandler(SIGHUP);
1317 if (ret < 0)
1318 return ret;
1319 ret = select_loop();
1320 if (ret >= 0) /* impossible */
1321 ret = -E_BUG;
1322 exit_hook(ret);
1323 return ret;
1324 }
1325
1326 static int com_prune(void)
1327 {
1328 int ret;
1329 struct snapshot_list sl;
1330 struct snapshot *victim;
1331 struct disk_space ds;
1332 const char *why;
1333
1334 lock_dss_or_die();
1335 ret = get_disk_space(".", &ds);
1336 if (ret < 0)
1337 return ret;
1338 log_disk_space(&ds);
1339 dss_get_snapshot_list(&sl);
1340 why = "outdated";
1341 victim = find_outdated_snapshot(&sl);
1342 if (victim)
1343 goto rm;
1344 why = "redundant";
1345 victim = find_redundant_snapshot(&sl);
1346 if (victim)
1347 goto rm;
1348 ret = 0;
1349 goto out;
1350 rm:
1351 if (conf.dry_run_given) {
1352 dss_msg("%s snapshot %s (interval = %i)\n",
1353 why, victim->name, victim->interval);
1354 ret = 0;
1355 goto out;
1356 }
1357 pre_remove_hook(victim, why);
1358 if (snapshot_removal_status == HS_PRE_RUNNING) {
1359 ret = wait_for_remove_process();
1360 if (ret < 0)
1361 goto out;
1362 if (snapshot_removal_status != HS_PRE_SUCCESS)
1363 goto out;
1364 }
1365 ret = exec_rm();
1366 if (ret < 0)
1367 goto out;
1368 ret = wait_for_remove_process();
1369 if (ret < 0)
1370 goto out;
1371 if (snapshot_removal_status != HS_SUCCESS)
1372 goto out;
1373 post_remove_hook();
1374 if (snapshot_removal_status != HS_POST_RUNNING)
1375 goto out;
1376 ret = wait_for_remove_process();
1377 if (ret < 0)
1378 goto out;
1379 ret = 1;
1380 out:
1381 free_snapshot_list(&sl);
1382 return ret;
1383 }
1384
1385 static int com_create(void)
1386 {
1387 int ret, status;
1388 char **rsync_argv;
1389
1390 lock_dss_or_die();
1391 if (conf.dry_run_given) {
1392 int i;
1393 char *msg = NULL;
1394 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1395 for (i = 0; rsync_argv[i]; i++) {
1396 char *tmp = msg;
1397 msg = make_message("%s%s%s", tmp? tmp : "",
1398 tmp? " " : "", rsync_argv[i]);
1399 free(tmp);
1400 }
1401 free_rsync_argv(rsync_argv);
1402 dss_msg("%s\n", msg);
1403 free(msg);
1404 return 1;
1405 }
1406 pre_create_hook();
1407 if (create_pid) {
1408 ret = wait_for_process(create_pid, &status);
1409 if (ret < 0)
1410 return ret;
1411 ret = handle_pre_create_hook_exit(status);
1412 if (ret <= 0) /* error, or pre-create failed */
1413 return ret;
1414 }
1415 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1416 ret = create_snapshot(rsync_argv);
1417 if (ret < 0)
1418 goto out;
1419 ret = wait_for_process(create_pid, &status);
1420 if (ret < 0)
1421 goto out;
1422 ret = handle_rsync_exit(status);
1423 if (ret < 0)
1424 goto out;
1425 post_create_hook();
1426 if (create_pid)
1427 ret = wait_for_process(create_pid, &status);
1428 out:
1429 free_rsync_argv(rsync_argv);
1430 return ret;
1431 }
1432
1433 static int com_ls(void)
1434 {
1435 int i;
1436 struct snapshot_list sl;
1437 struct snapshot *s;
1438
1439 dss_get_snapshot_list(&sl);
1440 FOR_EACH_SNAPSHOT(s, i, &sl) {
1441 int64_t d = 0;
1442 if (s->flags & SS_COMPLETE)
1443 d = (s->completion_time - s->creation_time) / 60;
1444 dss_msg("%u\t%s\t%3" PRId64 ":%02" PRId64 "\n", s->interval, s->name, d/60, d%60);
1445 };
1446 free_snapshot_list(&sl);
1447 return 1;
1448 }
1449
1450 static int setup_signal_handling(void)
1451 {
1452 int ret;
1453
1454 DSS_INFO_LOG(("setting up signal handlers\n"));
1455 signal_pipe = signal_init(); /* always successful */
1456 ret = install_sighandler(SIGINT);
1457 if (ret < 0)
1458 return ret;
1459 ret = install_sighandler(SIGTERM);
1460 if (ret < 0)
1461 return ret;
1462 return install_sighandler(SIGCHLD);
1463 }
1464
1465 /**
1466 * The main function of dss.
1467 *
1468 * \param argc Usual argument count.
1469 * \param argv Usual argument vector.
1470 */
1471 int main(int argc, char **argv)
1472 {
1473 int ret;
1474 struct cmdline_parser_params params;
1475
1476 params.override = 0;
1477 params.initialize = 1;
1478 params.check_required = 0;
1479 params.check_ambiguity = 0;
1480 params.print_errors = 1;
1481
1482 cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
1483 ret = parse_config_file(0);
1484 if (ret < 0)
1485 goto out;
1486 if (ret == 0) { /* no config file given */
1487 /*
1488 * Parse the command line options again, but this time check
1489 * that all required options are given.
1490 */
1491 struct cmdline_parser_params params;
1492 params.override = 1;
1493 params.initialize = 1;
1494 params.check_required = 1;
1495 params.check_ambiguity = 1;
1496 params.print_errors = 1;
1497 cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
1498 }
1499 if (conf.daemon_given)
1500 daemon_init();
1501 ret = change_to_dest_dir();
1502 if (ret < 0)
1503 goto out;
1504 dump_dss_config("startup");
1505 ret = setup_signal_handling();
1506 if (ret < 0)
1507 goto out;
1508 ret = call_command_handler();
1509 out:
1510 if (ret < 0)
1511 DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
1512 exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
1513 }