2 * Copyright (C) 2008-2011 Andre Noll <maan@tuebingen.mpg.de>
4 * Licensed under the GPL v2. For licencing details see COPYING.
11 #include <sys/types.h>
24 #include "gcc-compat.h"
38 /** Command line and config file options. */
39 static struct gengetopt_args_info conf;
40 /** Non-NULL if we log to a file. */
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 /** How many times in a row the rsync command failed. */
49 static int num_consecutive_rsync_errors;
50 /** Process id of current pre-remove/rm/post-remove process. */
51 static pid_t remove_pid;
52 /** When the next snapshot is due. */
53 static int64_t next_snapshot_time;
54 /** When to try to remove something. */
55 static struct timeval next_removal_check;
56 /** Creation time of the snapshot currently being created. */
57 static int64_t current_snapshot_creation_time;
58 /** The snapshot currently being removed. */
59 struct snapshot *snapshot_currently_being_removed;
60 /** Needed by the post-create hook. */
61 static char *path_to_last_complete_snapshot;
62 static char *name_of_reference_snapshot;
63 /** \sa \ref snap.h for details. */
64 enum hook_status snapshot_creation_status;
65 /** \sa \ref snap.h for details. */
66 enum hook_status snapshot_removal_status;
70 static const char *hook_status_description[] = {HOOK_STATUS_ARRAY};
72 /* may be called with ds == NULL. */
73 static int disk_space_low(struct disk_space *ds)
75 struct disk_space ds_struct;
78 int ret = get_disk_space(".", &ds_struct);
83 if (conf.min_free_mb_arg)
84 if (ds->free_mb < conf.min_free_mb_arg)
86 if (conf.min_free_percent_arg)
87 if (ds->percent_free < conf.min_free_percent_arg)
89 if (conf.min_free_percent_inodes_arg)
90 if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg)
95 static void dump_dss_config(const char *msg)
97 const char dash[] = "-----------------------------";
99 FILE *log = logfile? logfile : stderr;
100 struct disk_space ds;
101 int64_t now = get_current_time();
103 if (conf.loglevel_arg > INFO)
106 fprintf(log, "%s <%s config> %s\n", dash, msg, dash);
107 fprintf(log, "\n*** disk space ***\n\n");
108 ret = get_disk_space(".", &ds);
110 DSS_INFO_LOG(("disk space low: %s\n", disk_space_low(&ds)?
114 DSS_ERROR_LOG(("can not get free disk space: %s\n",
115 dss_strerror(-ret)));
117 /* we continue on errors from get_disk_space */
119 fprintf(log, "\n*** command line and config file options ***\n\n");
120 cmdline_parser_dump(log, &conf);
121 fprintf(log, "\n*** internal state ***\n\n");
125 "snapshot_currently_being_removed: %s\n"
126 "path_to_last_complete_snapshot: %s\n"
127 "reference_snapshot: %s\n"
128 "snapshot_creation_status: %s\n"
129 "snapshot_removal_status: %s\n"
130 "num_consecutive_rsync_errors: %d\n"
133 logfile? conf.logfile_arg : "stderr",
134 snapshot_currently_being_removed?
135 snapshot_currently_being_removed->name : "(none)",
136 path_to_last_complete_snapshot?
137 path_to_last_complete_snapshot : "(none)",
138 name_of_reference_snapshot?
139 name_of_reference_snapshot : "(none)",
140 hook_status_description[snapshot_creation_status],
141 hook_status_description[snapshot_removal_status],
142 num_consecutive_rsync_errors
146 "create_pid: %" PRId32 "\n"
147 "create process is %sstopped\n"
150 create_process_stopped? "" : "not "
153 fprintf(log, "remove_pid: %" PRId32 "\n", remove_pid);
154 if (next_snapshot_time != 0)
155 fprintf(log, "next snapshot due in %" PRId64 " seconds\n",
156 next_snapshot_time - now);
157 if (current_snapshot_creation_time != 0)
158 fprintf(log, "current_snapshot_creation_time: %"
159 PRId64 " (%" PRId64 " seconds ago)\n",
160 current_snapshot_creation_time,
161 now - current_snapshot_creation_time
163 if (next_removal_check.tv_sec != 0) {
164 fprintf(log, "next removal check: %llu (%llu seconds ago)\n",
165 (long long unsigned)next_removal_check.tv_sec,
166 now - (long long unsigned)next_removal_check.tv_sec
170 fprintf(log, "%s </%s config> %s\n", dash, msg, dash);
173 /* a litte cpp magic helps to DRY */
182 #define COMMAND(x) static int com_ ##x(void);
185 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
186 static int call_command_handler(void)
189 DSS_EMERG_LOG(("BUG: did not find command handler\n"));
195 static int loglevel = -1;
196 static const char *location_file = NULL;
197 static int location_line = -1;
198 static const char *location_func = NULL;
200 void dss_log_set_params(int ll, const char *file, int line, const char *func)
203 location_file = file;
204 location_line = line;
205 location_func = func;
209 * The log function of dss.
211 * \param ll Loglevel.
212 * \param fml Usual format string.
214 * All DSS_XXX_LOG() macros use this function.
216 __printf_1_2 void dss_log(const char* fmt,...)
224 if (loglevel < conf.loglevel_arg)
226 outfd = logfile? logfile : stderr;
229 strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
230 fprintf(outfd, "%s ", str);
231 if (conf.loglevel_arg <= INFO)
232 fprintf(outfd, "%i: ", loglevel);
233 #ifdef DSS_NO_FUNC_NAMES
234 fprintf(outfd, "%s:%d: ", location_file, location_line);
236 fprintf(outfd, "%s: ", location_func);
239 vfprintf(outfd, fmt, argp);
244 * Print a message either to stdout or to the log file.
246 static __printf_1_2 void dss_msg(const char* fmt,...)
248 FILE *outfd = conf.daemon_given? logfile : stdout;
251 vfprintf(outfd, fmt, argp);
255 static char *get_config_file_name(void)
257 char *home, *config_file;
259 if (conf.config_file_given)
260 return dss_strdup(conf.config_file_arg);
261 home = get_homedir();
262 config_file = make_message("%s/.dssrc", home);
267 static int send_signal(int sig)
270 char *config_file = get_config_file_name();
271 int ret = get_dss_pid(config_file, &pid);
276 if (conf.dry_run_given) {
277 dss_msg("%d\n", (int)pid);
280 ret = kill(pid, sig);
282 return -ERRNO_TO_DSS_ERROR(errno);
286 static int com_kill(void)
288 return send_signal(SIGTERM);
291 static int com_reload(void)
293 return send_signal(SIGHUP);
296 static void dss_get_snapshot_list(struct snapshot_list *sl)
298 get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
301 static int64_t compute_next_snapshot_time(void)
303 int64_t x = 0, now = get_current_time(), unit_interval
304 = 24 * 3600 * conf.unit_interval_arg, ret;
305 unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
306 num_complete_snapshots = 0;
308 struct snapshot *s = NULL;
309 struct snapshot_list sl;
311 dss_get_snapshot_list(&sl);
312 FOR_EACH_SNAPSHOT(s, i, &sl) {
313 if (!(s->flags & SS_COMPLETE))
315 num_complete_snapshots++;
316 x += s->completion_time - s->creation_time;
321 if (num_complete_snapshots == 0)
323 x /= num_complete_snapshots; /* avg time to create one snapshot */
324 if (unit_interval < x * wanted) /* oops, no sleep at all */
326 ret = s->completion_time + unit_interval / wanted - x;
328 free_snapshot_list(&sl);
332 static inline void invalidate_next_snapshot_time(void)
334 next_snapshot_time = 0;
337 static inline int next_snapshot_time_is_valid(void)
339 return next_snapshot_time != 0;
342 static int next_snapshot_is_due(void)
344 int64_t now = get_current_time();
346 if (!next_snapshot_time_is_valid())
347 next_snapshot_time = compute_next_snapshot_time();
348 if (next_snapshot_time <= now) {
349 DSS_DEBUG_LOG(("next snapshot: now\n"));
352 DSS_DEBUG_LOG(("next snapshot due in %" PRId64 " seconds\n",
353 next_snapshot_time - now));
357 static void pre_create_hook(void)
359 assert(snapshot_creation_status == HS_READY);
360 /* make sure that the next snapshot time will be recomputed */
361 invalidate_next_snapshot_time();
362 DSS_DEBUG_LOG(("executing %s\n", conf.pre_create_hook_arg));
363 dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg);
364 snapshot_creation_status = HS_PRE_RUNNING;
367 static void pre_remove_hook(struct snapshot *s, const char *why)
373 DSS_DEBUG_LOG(("%s snapshot %s\n", why, s->name));
374 assert(snapshot_removal_status == HS_READY);
375 assert(remove_pid == 0);
376 assert(!snapshot_currently_being_removed);
378 snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot));
379 *snapshot_currently_being_removed = *s;
380 snapshot_currently_being_removed->name = dss_strdup(s->name);
382 cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
383 conf.dest_dir_arg, s->name);
384 DSS_DEBUG_LOG(("executing %s\n", cmd));
385 dss_exec_cmdline_pid(&remove_pid, cmd);
387 snapshot_removal_status = HS_PRE_RUNNING;
390 static int exec_rm(void)
392 struct snapshot *s = snapshot_currently_being_removed;
393 char *new_name = being_deleted_name(s);
402 assert(snapshot_removal_status == HS_PRE_SUCCESS);
403 assert(remove_pid == 0);
405 DSS_NOTICE_LOG(("removing %s (interval = %i)\n", s->name, s->interval));
406 ret = dss_rename(s->name, new_name);
409 dss_exec(&remove_pid, argv[0], argv);
410 snapshot_removal_status = HS_RUNNING;
416 static int snapshot_is_being_created(struct snapshot *s)
418 return s->creation_time == current_snapshot_creation_time;
421 static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl)
426 DSS_DEBUG_LOG(("looking for orphaned snapshots\n"));
427 FOR_EACH_SNAPSHOT(s, i, sl) {
428 if (snapshot_is_being_created(s))
431 * We know that no rm is currently running, so if s is marked
432 * as being deleted, a previously started rm must have failed.
434 if (s->flags & SS_BEING_DELETED)
437 if (s->flags & SS_COMPLETE) /* good snapshot */
440 * This snapshot is incomplete and it is not the snapshot
441 * currently being created. However, we must not remove it if
442 * rsync is about to be restarted. As only the newest snapshot
443 * can be restarted, this snapshot is orphaned if it is not the
444 * newest snapshot or if we are not about to restart rsync.
446 if (get_newest_snapshot(sl) != s)
448 if (snapshot_creation_status != HS_NEEDS_RESTART)
451 /* no orphaned snapshots */
455 static int is_reference_snapshot(struct snapshot *s)
457 if (!name_of_reference_snapshot)
459 return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
463 * return: 0: no redundant snapshots, 1: rm process started, negative: error
465 static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
469 unsigned missing = 0;
471 DSS_DEBUG_LOG(("looking for intervals containing too many snapshots\n"));
472 for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
473 unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg);
474 unsigned num = sl->interval_count[interval];
475 struct snapshot *victim = NULL, *prev = NULL;
476 int64_t score = LONG_MAX;
479 missing += keep - num;
480 if (keep + missing >= num)
482 /* redundant snapshot in this interval, pick snapshot with lowest score */
483 FOR_EACH_SNAPSHOT(s, i, sl) {
486 if (snapshot_is_being_created(s))
488 if (is_reference_snapshot(s))
490 if (s->interval > interval) {
494 if (s->interval < interval)
502 /* check if s is a better victim */
503 this_score = s->creation_time - prev->creation_time;
504 assert(this_score >= 0);
505 if (this_score < score) {
517 static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl)
522 DSS_DEBUG_LOG(("looking for snapshots belonging to intervals >= %d\n",
523 conf.num_intervals_arg));
524 FOR_EACH_SNAPSHOT(s, i, sl) {
525 if (snapshot_is_being_created(s))
527 if (is_reference_snapshot(s))
529 if (s->interval < conf.num_intervals_arg)
536 static struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
539 struct snapshot *s, *ref = NULL;
541 num_complete = num_complete_snapshots(sl);
542 if (num_complete <= conf.min_complete_arg)
544 FOR_EACH_SNAPSHOT(s, i, sl) {
545 if (snapshot_is_being_created(s))
547 if (is_reference_snapshot(s)) { /* avoid this one */
551 DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name));
555 DSS_WARNING_LOG(("removing reference snapshot %s\n", ref->name));
559 static int rename_incomplete_snapshot(int64_t start)
566 * We don't want the dss_rename() below to fail with EEXIST because the
567 * last complete snapshot was created (and completed) in the same
568 * second as this one.
570 while ((now = get_current_time()) == start)
572 free(path_to_last_complete_snapshot);
573 ret = complete_name(start, now, &path_to_last_complete_snapshot);
576 old_name = incomplete_name(start);
577 ret = dss_rename(old_name, path_to_last_complete_snapshot);
579 DSS_NOTICE_LOG(("%s -> %s\n", old_name,
580 path_to_last_complete_snapshot));
585 static int try_to_free_disk_space(void)
588 struct snapshot_list sl;
589 struct snapshot *victim;
594 ret = disk_space_low(NULL);
597 low_disk_space = ret;
598 gettimeofday(&now, NULL);
599 if (tv_diff(&next_removal_check, &now, NULL) > 0)
601 if (!low_disk_space) {
602 if (conf.keep_redundant_given)
604 if (snapshot_creation_status != HS_READY)
606 if (next_snapshot_is_due())
610 * Idle and --keep_redundant not given, or low disk space. Look at
611 * existing snapshots.
613 dss_get_snapshot_list(&sl);
615 if (!low_disk_space && sl.num_snapshots <= 1)
618 victim = find_outdated_snapshot(&sl);
622 victim = find_redundant_snapshot(&sl);
625 /* try harder only if disk space is low */
629 victim = find_orphaned_snapshot(&sl);
632 DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n"));
633 victim = find_oldest_removable_snapshot(&sl);
636 DSS_CRIT_LOG(("uhuhu: disk space low and nothing to remove\n"));
637 ret = -ERRNO_TO_DSS_ERROR(ENOSPC);
640 pre_remove_hook(victim, why);
642 free_snapshot_list(&sl);
646 static void post_create_hook(void)
648 char *cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
649 conf.dest_dir_arg, path_to_last_complete_snapshot);
650 DSS_NOTICE_LOG(("executing %s\n", cmd));
651 dss_exec_cmdline_pid(&create_pid, cmd);
653 snapshot_creation_status = HS_POST_RUNNING;
656 static void post_remove_hook(void)
659 struct snapshot *s = snapshot_currently_being_removed;
663 cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
664 conf.dest_dir_arg, s->name);
665 DSS_NOTICE_LOG(("executing %s\n", cmd));
666 dss_exec_cmdline_pid(&remove_pid, cmd);
668 snapshot_removal_status = HS_POST_RUNNING;
671 static void dss_kill(pid_t pid, int sig, const char *msg)
673 const char *signame, *process_name;
678 case SIGTERM: signame = "TERM"; break;
679 case SIGSTOP: signame = "STOP"; break;
680 case SIGCONT: signame = "CONT"; break;
681 default: signame = "????";
684 if (pid == create_pid)
685 process_name = "create";
686 else if (pid == remove_pid)
687 process_name = "remove";
688 else process_name = "??????";
691 DSS_INFO_LOG(("%s\n", msg));
692 DSS_DEBUG_LOG(("sending signal %d (%s) to pid %d (%s process)\n",
693 sig, signame, (int)pid, process_name));
694 if (kill(pid, sig) >= 0)
696 DSS_INFO_LOG(("failed to send signal %d (%s) to pid %d (%s process)\n",
697 sig, signame, (int)pid, process_name));
700 static void stop_create_process(void)
702 if (create_process_stopped)
704 dss_kill(create_pid, SIGSTOP, "suspending create process");
705 create_process_stopped = 1;
708 static void restart_create_process(void)
710 if (!create_process_stopped)
712 dss_kill(create_pid, SIGCONT, "resuming create process");
713 create_process_stopped = 0;
717 * Print a log message about the exit status of a child.
719 static void log_termination_msg(pid_t pid, int status)
721 if (WIFEXITED(status))
722 DSS_INFO_LOG(("child %i exited. Exit status: %i\n", (int)pid,
723 WEXITSTATUS(status)));
724 else if (WIFSIGNALED(status))
725 DSS_NOTICE_LOG(("child %i was killed by signal %i\n", (int)pid,
728 DSS_WARNING_LOG(("child %i terminated abormally\n", (int)pid));
731 static int wait_for_process(pid_t pid, int *status)
735 DSS_DEBUG_LOG(("Waiting for process %d to terminate\n", (int)pid));
740 FD_SET(signal_pipe, &rfds);
741 ret = dss_select(signal_pipe + 1, &rfds, NULL, NULL);
747 if (ret == SIGCHLD) {
748 ret = waitpid(pid, status, 0);
751 if (errno != EINTR) { /* error */
752 ret = -ERRNO_TO_DSS_ERROR(errno);
756 /* SIGINT or SIGTERM */
757 dss_kill(pid, SIGTERM, "killing child process");
760 DSS_ERROR_LOG(("failed to wait for process %d\n", (int)pid));
762 log_termination_msg(pid, *status);
766 static void handle_pre_remove_exit(int status)
768 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
769 snapshot_removal_status = HS_READY;
770 gettimeofday(&next_removal_check, NULL);
771 next_removal_check.tv_sec += 60;
774 snapshot_removal_status = HS_PRE_SUCCESS;
777 static int handle_rm_exit(int status)
779 if (!WIFEXITED(status)) {
780 snapshot_removal_status = HS_READY;
781 return -E_INVOLUNTARY_EXIT;
783 if (WEXITSTATUS(status)) {
784 snapshot_removal_status = HS_READY;
785 return -E_BAD_EXIT_CODE;
787 snapshot_removal_status = HS_SUCCESS;
791 static void handle_post_remove_exit(void)
793 snapshot_removal_status = HS_READY;
796 static int handle_remove_exit(int status)
799 struct snapshot *s = snapshot_currently_being_removed;
802 switch (snapshot_removal_status) {
804 handle_pre_remove_exit(status);
808 ret = handle_rm_exit(status);
810 case HS_POST_RUNNING:
811 handle_post_remove_exit();
817 if (snapshot_removal_status == HS_READY) {
820 snapshot_currently_being_removed = NULL;
826 static int wait_for_remove_process(void)
832 snapshot_removal_status == HS_PRE_RUNNING ||
833 snapshot_removal_status == HS_RUNNING ||
834 snapshot_removal_status == HS_POST_RUNNING
836 ret = wait_for_process(remove_pid, &status);
839 return handle_remove_exit(status);
842 static int handle_rsync_exit(int status)
846 if (!WIFEXITED(status)) {
847 DSS_ERROR_LOG(("rsync process %d died involuntary\n", (int)create_pid));
848 ret = -E_INVOLUNTARY_EXIT;
849 snapshot_creation_status = HS_READY;
852 es = WEXITSTATUS(status);
854 * Restart rsync on non-fatal errors:
855 * 24: Partial transfer due to vanished source files
857 if (es != 0 && es != 24) {
858 DSS_WARNING_LOG(("rsync exit code %d, error count %d\n",
859 es, ++num_consecutive_rsync_errors));
860 if (num_consecutive_rsync_errors > conf.max_rsync_errors_arg) {
861 ret = -E_TOO_MANY_RSYNC_ERRORS;
862 snapshot_creation_status = HS_READY;
865 DSS_WARNING_LOG(("restarting rsync process\n"));
866 snapshot_creation_status = HS_NEEDS_RESTART;
867 next_snapshot_time = get_current_time() + 60;
871 num_consecutive_rsync_errors = 0;
872 ret = rename_incomplete_snapshot(current_snapshot_creation_time);
875 snapshot_creation_status = HS_SUCCESS;
876 free(name_of_reference_snapshot);
877 name_of_reference_snapshot = NULL;
879 create_process_stopped = 0;
883 static int handle_pre_create_hook_exit(int status)
886 static int warn_count;
888 if (!WIFEXITED(status)) {
889 snapshot_creation_status = HS_READY;
890 ret = -E_INVOLUNTARY_EXIT;
893 es = WEXITSTATUS(status);
896 DSS_NOTICE_LOG(("pre_create_hook %s returned %d\n",
897 conf.pre_create_hook_arg, es));
898 DSS_NOTICE_LOG(("deferring snapshot creation...\n"));
899 warn_count = 60; /* warn only once per hour */
901 next_snapshot_time = get_current_time() + 60;
902 snapshot_creation_status = HS_READY;
907 snapshot_creation_status = HS_PRE_SUCCESS;
913 static int handle_sigchld(void)
916 int status, ret = reap_child(&pid, &status);
921 if (pid == create_pid) {
922 switch (snapshot_creation_status) {
924 ret = handle_pre_create_hook_exit(status);
927 ret = handle_rsync_exit(status);
929 case HS_POST_RUNNING:
930 snapshot_creation_status = HS_READY;
934 DSS_EMERG_LOG(("BUG: create can't die in status %d\n",
935 snapshot_creation_status));
941 if (pid == remove_pid) {
942 ret = handle_remove_exit(status);
947 DSS_EMERG_LOG(("BUG: unknown process %d died\n", (int)pid));
951 static int check_config(void)
953 if (conf.unit_interval_arg <= 0) {
954 DSS_ERROR_LOG(("bad unit interval: %i\n", conf.unit_interval_arg));
955 return -E_INVALID_NUMBER;
957 DSS_DEBUG_LOG(("unit interval: %i day(s)\n", conf.unit_interval_arg));
958 if (conf.num_intervals_arg <= 0 || conf.num_intervals_arg > 30) {
959 DSS_ERROR_LOG(("bad number of intervals: %i\n",
960 conf.num_intervals_arg));
961 return -E_INVALID_NUMBER;
963 DSS_DEBUG_LOG(("number of intervals: %i\n", conf.num_intervals_arg));
968 * Returns < 0 on errors, 0 if no config file is given and > 0 if the config
969 * file was read successfully.
971 static int parse_config_file(int override)
973 int ret, config_file_exists;
974 char *config_file = get_config_file_name();
976 char *old_logfile_arg = NULL;
977 int old_daemon_given = 0;
979 if (override) { /* SIGHUP */
980 if (conf.logfile_given)
981 old_logfile_arg = dss_strdup(conf.logfile_arg);
982 old_daemon_given = conf.daemon_given;
985 config_file_exists = !stat(config_file, &statbuf);
986 if (!config_file_exists && conf.config_file_given) {
987 ret = -ERRNO_TO_DSS_ERROR(errno);
988 DSS_ERROR_LOG(("failed to stat config file %s\n", config_file));
991 if (config_file_exists) {
992 struct cmdline_parser_params params;
993 params.override = override;
994 params.initialize = 0;
995 params.check_required = 1;
996 params.check_ambiguity = 0;
997 params.print_errors = 1;
998 if (override) { /* invalidate all rsync options */
1001 for (i = 0; i < conf.rsync_option_given; i++) {
1002 free(conf.rsync_option_arg[i]);
1003 conf.rsync_option_arg[i] = NULL;
1005 conf.rsync_option_given = 0;
1007 cmdline_parser_config_file(config_file, &conf, ¶ms);
1009 ret = check_config();
1013 /* don't change daemon mode on SIGHUP */
1014 conf.daemon_given = old_daemon_given;
1017 if (conf.logfile_given)
1018 free(old_logfile_arg);
1019 else if (conf.daemon_given) { /* re-use old logfile */
1020 conf.logfile_arg = old_logfile_arg;
1021 conf.logfile_given = 1;
1024 if (conf.logfile_given && conf.run_given && conf.daemon_given) {
1025 logfile = open_log(conf.logfile_arg);
1026 log_welcome(conf.loglevel_arg);
1028 DSS_DEBUG_LOG(("loglevel: %d\n", conf.loglevel_arg));
1029 ret = config_file_exists;
1033 DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
1037 static int change_to_dest_dir(void)
1039 DSS_INFO_LOG(("changing cwd to %s\n", conf.dest_dir_arg));
1040 return dss_chdir(conf.dest_dir_arg);
1043 static int handle_sighup(void)
1047 DSS_NOTICE_LOG(("SIGHUP, re-reading config\n"));
1048 dump_dss_config("old");
1049 ret = parse_config_file(1);
1052 dump_dss_config("reloaded");
1053 invalidate_next_snapshot_time();
1054 return change_to_dest_dir();
1057 static void kill_children(void)
1059 restart_create_process();
1060 dss_kill(create_pid, SIGTERM, NULL);
1061 dss_kill(remove_pid, SIGTERM, NULL);
1064 static int handle_signal(void)
1066 int sig, ret = next_signal();
1078 ret = handle_sighup();
1081 ret = handle_sigchld();
1086 DSS_ERROR_LOG(("%s\n", dss_strerror(-ret)));
1091 * We can not use rsync locally if the local user is different from the remote
1092 * user or if the src dir is not on the local host (or both).
1094 static int use_rsync_locally(char *logname)
1096 char *h = conf.remote_host_arg;
1098 if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1"))
1100 if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname))
1105 static int rename_resume_snap(int64_t creation_time)
1107 struct snapshot_list sl;
1108 struct snapshot *s = NULL;
1109 char *new_name = incomplete_name(creation_time);
1113 sl.num_snapshots = 0;
1116 if (conf.no_resume_given)
1118 dss_get_snapshot_list(&sl);
1120 * Snapshot recycling: We first look at the newest snapshot. If this
1121 * snapshot happens to be incomplete, the last rsync process was
1122 * aborted and we reuse this one. Otherwise we look at snapshots which
1123 * could be removed (outdated and redundant snapshots) as candidates
1124 * for recycling. If no outdated/redundant snapshot exists, we check if
1125 * there is an orphaned snapshot, which likely is useless anyway.
1127 * Only if no existing snapshot is suitable for recycling, we bite the
1128 * bullet and create a new one.
1130 s = get_newest_snapshot(&sl);
1131 if (!s) /* no snapshots at all */
1133 /* re-use last snapshot if it is incomplete */
1135 if ((s->flags & SS_COMPLETE) == 0)
1138 s = find_outdated_snapshot(&sl);
1142 s = find_redundant_snapshot(&sl);
1146 s = find_orphaned_snapshot(&sl);
1149 DSS_INFO_LOG(("reusing %s snapshot %s\n", why, s->name));
1150 ret = dss_rename(s->name, new_name);
1153 DSS_NOTICE_LOG(("creating new snapshot %s\n", new_name));
1155 free_snapshot_list(&sl);
1159 static void create_rsync_argv(char ***argv, int64_t *num)
1163 struct snapshot_list sl;
1165 dss_get_snapshot_list(&sl);
1166 assert(!name_of_reference_snapshot);
1167 name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
1168 free_snapshot_list(&sl);
1170 *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
1171 (*argv)[i++] = dss_strdup("rsync");
1172 (*argv)[i++] = dss_strdup("-a");
1173 (*argv)[i++] = dss_strdup("--delete");
1174 for (j = 0; j < conf.rsync_option_given; j++)
1175 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
1176 if (name_of_reference_snapshot) {
1177 DSS_INFO_LOG(("using %s as reference\n", name_of_reference_snapshot));
1178 (*argv)[i++] = make_message("--link-dest=../%s",
1179 name_of_reference_snapshot);
1181 DSS_INFO_LOG(("no suitable reference snapshot found\n"));
1182 logname = dss_logname();
1183 if (use_rsync_locally(logname))
1184 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
1186 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
1187 conf.remote_user_arg : logname,
1188 conf.remote_host_arg, conf.source_dir_arg);
1190 *num = get_current_time();
1191 (*argv)[i++] = incomplete_name(*num);
1192 (*argv)[i++] = NULL;
1193 for (j = 0; j < i; j++)
1194 DSS_DEBUG_LOG(("argv[%d] = %s\n", j, (*argv)[j]));
1197 static void free_rsync_argv(char **argv)
1203 for (i = 0; argv[i]; i++)
1208 static int create_snapshot(char **argv)
1212 ret = rename_resume_snap(current_snapshot_creation_time);
1215 dss_exec(&create_pid, argv[0], argv);
1216 snapshot_creation_status = HS_RUNNING;
1220 static int select_loop(void)
1223 /* check every 60 seconds for free disk space */
1225 char **rsync_argv = NULL;
1229 struct timeval *tvp;
1232 tvp = NULL; /* sleep until rm hook/process dies */
1233 else { /* sleep one minute */
1239 FD_SET(signal_pipe, &rfds);
1240 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
1243 if (FD_ISSET(signal_pipe, &rfds)) {
1244 ret = handle_signal();
1250 if (snapshot_removal_status == HS_PRE_SUCCESS) {
1256 if (snapshot_removal_status == HS_SUCCESS) {
1260 ret = try_to_free_disk_space();
1263 if (snapshot_removal_status != HS_READY) {
1264 stop_create_process();
1267 restart_create_process();
1268 switch (snapshot_creation_status) {
1270 if (!next_snapshot_is_due())
1274 case HS_PRE_RUNNING:
1276 case HS_POST_RUNNING:
1278 case HS_PRE_SUCCESS:
1279 if (!name_of_reference_snapshot) {
1280 free_rsync_argv(rsync_argv);
1281 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1283 ret = create_snapshot(rsync_argv);
1287 case HS_NEEDS_RESTART:
1288 if (!next_snapshot_is_due())
1290 ret = create_snapshot(rsync_argv);
1303 static void exit_hook(int exit_code)
1308 argv[0] = conf.exit_hook_arg;
1309 argv[1] = dss_strerror(-exit_code);
1312 DSS_NOTICE_LOG(("executing %s %s\n", argv[0], argv[1]));
1313 dss_exec(&pid, conf.exit_hook_arg, argv);
1316 static void lock_dss_or_die(void)
1318 char *config_file = get_config_file_name();
1319 int ret = lock_dss(config_file);
1323 DSS_EMERG_LOG(("failed to lock: %s\n", dss_strerror(-ret)));
1328 static int com_run(void)
1333 if (conf.dry_run_given) {
1334 DSS_ERROR_LOG(("dry_run not supported by this command\n"));
1337 ret = install_sighandler(SIGHUP);
1340 ret = select_loop();
1341 if (ret >= 0) /* impossible */
1348 static int com_prune(void)
1351 struct snapshot_list sl;
1352 struct snapshot *victim;
1353 struct disk_space ds;
1357 ret = get_disk_space(".", &ds);
1360 log_disk_space(&ds);
1361 dss_get_snapshot_list(&sl);
1363 victim = find_outdated_snapshot(&sl);
1367 victim = find_redundant_snapshot(&sl);
1373 if (conf.dry_run_given) {
1374 dss_msg("%s snapshot %s (interval = %i)\n",
1375 why, victim->name, victim->interval);
1379 pre_remove_hook(victim, why);
1380 if (snapshot_removal_status == HS_PRE_RUNNING) {
1381 ret = wait_for_remove_process();
1384 if (snapshot_removal_status != HS_PRE_SUCCESS)
1390 ret = wait_for_remove_process();
1393 if (snapshot_removal_status != HS_SUCCESS)
1396 if (snapshot_removal_status != HS_POST_RUNNING)
1398 ret = wait_for_remove_process();
1403 free_snapshot_list(&sl);
1407 static int com_create(void)
1413 if (conf.dry_run_given) {
1416 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1417 for (i = 0; rsync_argv[i]; i++) {
1419 msg = make_message("%s%s%s", tmp? tmp : "",
1420 tmp? " " : "", rsync_argv[i]);
1423 free_rsync_argv(rsync_argv);
1424 dss_msg("%s\n", msg);
1430 ret = wait_for_process(create_pid, &status);
1433 ret = handle_pre_create_hook_exit(status);
1434 if (ret <= 0) /* error, or pre-create failed */
1437 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1438 ret = create_snapshot(rsync_argv);
1441 ret = wait_for_process(create_pid, &status);
1444 ret = handle_rsync_exit(status);
1449 ret = wait_for_process(create_pid, &status);
1451 free_rsync_argv(rsync_argv);
1455 static int com_ls(void)
1458 struct snapshot_list sl;
1461 dss_get_snapshot_list(&sl);
1462 FOR_EACH_SNAPSHOT(s, i, &sl) {
1464 if (s->flags & SS_COMPLETE)
1465 d = (s->completion_time - s->creation_time) / 60;
1466 dss_msg("%u\t%s\t%3" PRId64 ":%02" PRId64 "\n", s->interval, s->name, d/60, d%60);
1468 free_snapshot_list(&sl);
1472 static int setup_signal_handling(void)
1476 DSS_INFO_LOG(("setting up signal handlers\n"));
1477 signal_pipe = signal_init(); /* always successful */
1478 ret = install_sighandler(SIGINT);
1481 ret = install_sighandler(SIGTERM);
1484 return install_sighandler(SIGCHLD);
1488 * The main function of dss.
1490 * \param argc Usual argument count.
1491 * \param argv Usual argument vector.
1493 int main(int argc, char **argv)
1496 struct cmdline_parser_params params;
1498 params.override = 0;
1499 params.initialize = 1;
1500 params.check_required = 0;
1501 params.check_ambiguity = 0;
1502 params.print_errors = 1;
1504 cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */
1505 ret = parse_config_file(0);
1508 if (ret == 0) { /* no config file given */
1510 * Parse the command line options again, but this time check
1511 * that all required options are given.
1513 struct cmdline_parser_params params;
1514 params.override = 1;
1515 params.initialize = 1;
1516 params.check_required = 1;
1517 params.check_ambiguity = 1;
1518 params.print_errors = 1;
1519 cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */
1521 if (conf.daemon_given)
1523 ret = change_to_dest_dir();
1526 dump_dss_config("startup");
1527 ret = setup_signal_handling();
1530 ret = call_command_handler();
1534 DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
1535 exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);