2 * Copyright (C) 2008-2010 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
11 #include <sys/types.h>
24 #include "gcc-compat.h"
37 /** Command line and config file options. */
38 static struct gengetopt_args_info conf;
39 /** Non-NULL if we log to a file. */
41 /** The read end of the signal pipe */
42 static int signal_pipe;
43 /** Process id of current pre-create-hook/rsync/post-create-hook process. */
44 static pid_t create_pid;
45 /** Whether the pre-create-hook/rsync/post-create-hook is currently stopped. */
46 static int create_process_stopped;
47 /** Process id of current pre-remove/rm/post-remove process. */
48 static pid_t remove_pid;
49 /** When the next snapshot is due. */
50 static int64_t next_snapshot_time;
51 /** When to try to remove something. */
52 static struct timeval next_removal_check;
53 /** Creation time of the snapshot currently being created. */
54 static int64_t current_snapshot_creation_time;
55 /** The snapshot currently being removed. */
56 struct snapshot *snapshot_currently_being_removed;
57 /** Needed by the post-create hook. */
58 static char *path_to_last_complete_snapshot;
59 static char *name_of_reference_snapshot;
60 /** \sa \ref snap.h for details. */
61 enum hook_status snapshot_creation_status;
62 /** \sa \ref snap.h for details. */
63 enum hook_status snapshot_removal_status;
67 static const char const *hook_status_description[] = {HOOK_STATUS_ARRAY};
69 /* may be called with ds == NULL. */
70 static int disk_space_low(struct disk_space *ds)
72 struct disk_space ds_struct;
75 int ret = get_disk_space(".", &ds_struct);
80 if (conf.min_free_mb_arg)
81 if (ds->free_mb < conf.min_free_mb_arg)
83 if (conf.min_free_percent_arg)
84 if (ds->percent_free < conf.min_free_percent_arg)
86 if (conf.min_free_percent_inodes_arg)
87 if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg)
92 static void dump_dss_config(const char *msg)
94 const char dash[] = "-----------------------------";
96 FILE *log = logfile? logfile : stderr;
98 int64_t now = get_current_time();
100 if (conf.loglevel_arg > INFO)
103 fprintf(log, "%s <%s config> %s\n", dash, msg, dash);
104 fprintf(log, "\n*** disk space ***\n\n");
105 ret = get_disk_space(".", &ds);
107 DSS_INFO_LOG("disk space low: %s\n", disk_space_low(&ds)?
111 DSS_ERROR_LOG("can not get free disk space: %s\n",
114 /* we continue on errors from get_disk_space */
116 fprintf(log, "\n*** command line and config file options ***\n\n");
117 cmdline_parser_dump(log, &conf);
118 fprintf(log, "\n*** internal state ***\n\n");
122 "snapshot_currently_being_removed: %s\n"
123 "path_to_last_complete_snapshot: %s\n"
124 "reference_snapshot: %s\n"
125 "snapshot_creation_status: %s\n"
126 "snapshot_removal_status: %s\n"
129 logfile? conf.logfile_arg : "stderr",
130 snapshot_currently_being_removed?
131 snapshot_currently_being_removed->name : "(none)",
132 path_to_last_complete_snapshot?
133 path_to_last_complete_snapshot : "(none)",
134 name_of_reference_snapshot?
135 name_of_reference_snapshot : "(none)",
136 hook_status_description[snapshot_creation_status],
137 hook_status_description[snapshot_removal_status]
141 "create_pid: %" PRId32 "\n"
142 "create process is %sstopped\n"
145 create_process_stopped? "" : "not "
148 fprintf(log, "remove_pid: %" PRId32 "\n", remove_pid);
149 if (next_snapshot_time != 0)
150 fprintf(log, "next snapshot due in %" PRId64 " seconds\n",
151 next_snapshot_time - now);
152 if (current_snapshot_creation_time != 0)
153 fprintf(log, "current_snapshot_creation_time: %"
154 PRId64 " (%" PRId64 " seconds ago)\n",
155 current_snapshot_creation_time,
156 now - current_snapshot_creation_time
158 if (next_removal_check.tv_sec != 0) {
159 fprintf(log, "next removal check: %llu (%llu seconds ago)\n",
160 (long long unsigned)next_removal_check.tv_sec,
161 now - (long long unsigned)next_removal_check.tv_sec
165 fprintf(log, "%s </%s config> %s\n", dash, msg, dash);
168 /* a litte cpp magic helps to DRY */
174 #define COMMAND(x) static int com_ ##x(void);
177 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
178 static int call_command_handler(void)
181 DSS_EMERG_LOG("BUG: did not find command handler\n");
188 * The log function of dss.
190 * \param ll Loglevel.
191 * \param fml Usual format string.
193 * All DSS_XXX_LOG() macros use this function.
195 __printf_2_3 void dss_log(int ll, const char* fmt,...)
203 if (ll < conf.loglevel_arg)
205 outfd = logfile? logfile : stderr;
208 strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
209 fprintf(outfd, "%s ", str);
210 if (conf.loglevel_arg <= INFO)
211 fprintf(outfd, "%i: ", ll);
213 vfprintf(outfd, fmt, argp);
218 * Print a message either to stdout or to the log file.
220 static __printf_1_2 void dss_msg(const char* fmt,...)
222 FILE *outfd = conf.daemon_given? logfile : stdout;
225 vfprintf(outfd, fmt, argp);
229 static void dss_get_snapshot_list(struct snapshot_list *sl)
231 get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
234 static int64_t compute_next_snapshot_time(void)
236 int64_t x = 0, now = get_current_time(), unit_interval
237 = 24 * 3600 * conf.unit_interval_arg, ret;
238 unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
239 num_complete_snapshots = 0;
241 struct snapshot *s = NULL;
242 struct snapshot_list sl;
244 dss_get_snapshot_list(&sl);
245 FOR_EACH_SNAPSHOT(s, i, &sl) {
246 if (!(s->flags & SS_COMPLETE))
248 num_complete_snapshots++;
249 x += s->completion_time - s->creation_time;
254 if (num_complete_snapshots == 0)
256 x /= num_complete_snapshots; /* avg time to create one snapshot */
257 if (unit_interval < x * wanted) /* oops, no sleep at all */
259 ret = s->completion_time + unit_interval / wanted - x;
261 free_snapshot_list(&sl);
265 static inline void invalidate_next_snapshot_time(void)
267 next_snapshot_time = 0;
270 static inline int next_snapshot_time_is_valid(void)
272 return next_snapshot_time != 0;
275 static int next_snapshot_is_due(void)
277 int64_t now = get_current_time();
279 if (!next_snapshot_time_is_valid())
280 next_snapshot_time = compute_next_snapshot_time();
281 if (next_snapshot_time <= now) {
282 DSS_DEBUG_LOG("next snapshot: now\n");
285 DSS_DEBUG_LOG("next snapshot due in %" PRId64 " seconds\n",
286 next_snapshot_time - now);
290 static int pre_create_hook(void)
292 int ret, fds[3] = {0, 0, 0};
294 assert(snapshot_creation_status == HS_READY);
295 /* make sure that the next snapshot time will be recomputed */
296 invalidate_next_snapshot_time();
297 DSS_DEBUG_LOG("executing %s\n", conf.pre_create_hook_arg);
298 ret = dss_exec_cmdline_pid(&create_pid,
299 conf.pre_create_hook_arg, fds);
302 snapshot_creation_status = HS_PRE_RUNNING;
306 static int pre_remove_hook(struct snapshot *s, const char *why)
308 int ret, fds[3] = {0, 0, 0};
313 DSS_DEBUG_LOG("%s snapshot %s\n", why, s->name);
314 assert(snapshot_removal_status == HS_READY);
315 assert(remove_pid == 0);
316 assert(!snapshot_currently_being_removed);
318 snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot));
319 *snapshot_currently_being_removed = *s;
320 snapshot_currently_being_removed->name = dss_strdup(s->name);
322 cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
323 conf.dest_dir_arg, s->name);
324 DSS_DEBUG_LOG("executing %s\n", cmd);
325 ret = dss_exec_cmdline_pid(&remove_pid, cmd, fds);
329 snapshot_removal_status = HS_PRE_RUNNING;
333 static int exec_rm(void)
335 struct snapshot *s = snapshot_currently_being_removed;
336 int fds[3] = {0, 0, 0};
337 char *new_name = being_deleted_name(s);
338 char *argv[] = {"rm", "-rf", new_name, NULL};
341 assert(snapshot_removal_status == HS_PRE_SUCCESS);
342 assert(remove_pid == 0);
344 DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval);
345 ret = dss_rename(s->name, new_name);
348 ret = dss_exec(&remove_pid, argv[0], argv, fds);
351 snapshot_removal_status = HS_RUNNING;
357 static int snapshot_is_being_created(struct snapshot *s)
359 return s->creation_time == current_snapshot_creation_time;
362 static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl)
367 DSS_DEBUG_LOG("looking for orphaned snapshots\n");
368 FOR_EACH_SNAPSHOT(s, i, sl) {
369 if (snapshot_is_being_created(s))
372 * We know that no rm is currently running, so if s is marked
373 * as being deleted, a previously started rm must have failed.
375 if (s->flags & SS_BEING_DELETED)
378 if (s->flags & SS_COMPLETE) /* good snapshot */
381 * This snapshot is incomplete and it is not the snapshot
382 * currently being created. However, we must not remove it if
383 * rsync is about to be restarted. As only the newest snapshot
384 * can be restarted, this snapshot is orphaned if it is not the
385 * newest snapshot or if we are not about to restart rsync.
387 if (get_newest_snapshot(sl) != s)
389 if (snapshot_creation_status != HS_NEEDS_RESTART)
392 /* no orphaned snapshots */
396 static int is_reference_snapshot(struct snapshot *s)
398 if (!name_of_reference_snapshot)
400 return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
404 * return: 0: no redundant snapshots, 1: rm process started, negative: error
406 static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
410 unsigned missing = 0;
412 DSS_DEBUG_LOG("looking for intervals containing too many snapshots\n");
413 for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
414 unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg);
415 unsigned num = sl->interval_count[interval];
416 struct snapshot *victim = NULL, *prev = NULL;
417 int64_t score = LONG_MAX;
420 missing += keep - num;
421 // DSS_DEBUG_LOG("interval %i: keep: %u, have: %u, missing: %u\n",
422 // interval, keep, num, missing);
423 if (keep + missing >= num)
425 /* redundant snapshot in this interval, pick snapshot with lowest score */
426 FOR_EACH_SNAPSHOT(s, i, sl) {
429 if (snapshot_is_being_created(s))
431 if (is_reference_snapshot(s))
433 //DSS_DEBUG_LOG("checking %s\n", s->name);
434 if (s->interval > interval) {
438 if (s->interval < interval)
446 /* check if s is a better victim */
447 this_score = s->creation_time - prev->creation_time;
448 assert(this_score >= 0);
449 //DSS_DEBUG_LOG("%s: score %lli\n", s->name, (long long)score);
450 if (this_score < score) {
462 static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl)
467 DSS_DEBUG_LOG("looking for snapshots belonging to intervals >= %d\n",
468 conf.num_intervals_arg);
469 FOR_EACH_SNAPSHOT(s, i, sl) {
470 if (snapshot_is_being_created(s))
472 if (is_reference_snapshot(s))
474 if (s->interval < conf.num_intervals_arg)
481 struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
485 FOR_EACH_SNAPSHOT(s, i, sl) {
486 if (snapshot_is_being_created(s))
488 if (is_reference_snapshot(s))
490 DSS_INFO_LOG("oldest removable snapshot: %s\n", s->name);
496 static int rename_incomplete_snapshot(int64_t start)
501 free(path_to_last_complete_snapshot);
502 ret = complete_name(start, get_current_time(),
503 &path_to_last_complete_snapshot);
506 old_name = incomplete_name(start);
507 ret = dss_rename(old_name, path_to_last_complete_snapshot);
509 DSS_NOTICE_LOG("%s -> %s\n", old_name,
510 path_to_last_complete_snapshot);
515 static int try_to_free_disk_space(void)
518 struct snapshot_list sl;
519 struct snapshot *victim;
524 ret = disk_space_low(NULL);
527 low_disk_space = ret;
528 gettimeofday(&now, NULL);
529 if (tv_diff(&next_removal_check, &now, NULL) > 0)
531 if (!low_disk_space) {
532 if (conf.keep_redundant_given)
534 if (snapshot_creation_status != HS_READY)
536 if (next_snapshot_is_due())
539 dss_get_snapshot_list(&sl);
541 if (!low_disk_space && sl.num_snapshots <= 1)
544 victim = find_outdated_snapshot(&sl);
548 victim = find_redundant_snapshot(&sl);
551 /* try harder only if disk space is low */
555 victim = find_orphaned_snapshot(&sl);
558 DSS_WARNING_LOG("disk space low and nothing obvious to remove\n");
559 victim = find_oldest_removable_snapshot(&sl);
562 DSS_CRIT_LOG("uhuhu: disk space low and nothing to remove\n");
563 ret = -ERRNO_TO_DSS_ERROR(ENOSPC);
566 ret = pre_remove_hook(victim, why);
568 free_snapshot_list(&sl);
572 static int post_create_hook(void)
574 int ret, fds[3] = {0, 0, 0};
577 cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
578 conf.dest_dir_arg, path_to_last_complete_snapshot);
579 DSS_NOTICE_LOG("executing %s\n", cmd);
580 ret = dss_exec_cmdline_pid(&create_pid, cmd, fds);
584 snapshot_creation_status = HS_POST_RUNNING;
588 static int post_remove_hook(void)
590 int ret, fds[3] = {0, 0, 0};
592 struct snapshot *s = snapshot_currently_being_removed;
596 cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
597 conf.dest_dir_arg, s->name);
598 DSS_NOTICE_LOG("executing %s\n", cmd);
599 ret = dss_exec_cmdline_pid(&remove_pid, cmd, fds);
603 snapshot_removal_status = HS_POST_RUNNING;
607 static void dss_kill(pid_t pid, int sig, const char *msg)
609 const char *signame, *process_name;
614 case SIGTERM: signame = "TERM"; break;
615 case SIGSTOP: signame = "STOP"; break;
616 case SIGCONT: signame = "CONT"; break;
617 default: signame = "????";
620 if (pid == create_pid)
621 process_name = "create";
622 else if (pid == remove_pid)
623 process_name = "remove";
624 else process_name = "??????";
627 DSS_INFO_LOG("%s\n", msg);
628 DSS_DEBUG_LOG("sending signal %d (%s) to pid %d (%s process)\n",
629 sig, signame, (int)pid, process_name);
630 if (kill(pid, sig) >= 0)
632 DSS_INFO_LOG("failed to send signal %d (%s) to pid %d (%s process)\n",
633 sig, signame, (int)pid, process_name);
636 static void stop_create_process(void)
638 if (create_process_stopped)
640 dss_kill(create_pid, SIGSTOP, "suspending create process");
641 create_process_stopped = 1;
644 static void restart_create_process(void)
646 if (!create_process_stopped)
648 dss_kill(create_pid, SIGCONT, "resuming create process");
649 create_process_stopped = 0;
653 * Print a log message about the exit status of a child.
655 static void log_termination_msg(pid_t pid, int status)
657 if (WIFEXITED(status))
658 DSS_INFO_LOG("child %i exited. Exit status: %i\n", (int)pid,
659 WEXITSTATUS(status));
660 else if (WIFSIGNALED(status))
661 DSS_NOTICE_LOG("child %i was killed by signal %i\n", (int)pid,
664 DSS_WARNING_LOG("child %i terminated abormally\n", (int)pid);
667 static int wait_for_process(pid_t pid, int *status)
671 DSS_DEBUG_LOG("Waiting for process %d to terminate\n", (int)pid);
676 FD_SET(signal_pipe, &rfds);
677 ret = dss_select(signal_pipe + 1, &rfds, NULL, NULL);
683 if (ret == SIGCHLD) {
684 ret = waitpid(pid, status, 0);
687 if (errno != EINTR) { /* error */
688 ret = -ERRNO_TO_DSS_ERROR(errno);
692 /* SIGINT or SIGTERM */
693 dss_kill(pid, SIGTERM, "killing child process");
696 DSS_ERROR_LOG("failed to wait for process %d\n", (int)pid);
698 log_termination_msg(pid, *status);
702 static void handle_pre_remove_exit(int status)
704 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
705 snapshot_removal_status = HS_READY;
706 gettimeofday(&next_removal_check, NULL);
707 next_removal_check.tv_sec += 60;
710 snapshot_removal_status = HS_PRE_SUCCESS;
713 static int handle_rm_exit(int status)
715 if (!WIFEXITED(status)) {
716 snapshot_removal_status = HS_READY;
717 return -E_INVOLUNTARY_EXIT;
719 if (WEXITSTATUS(status)) {
720 snapshot_removal_status = HS_READY;
721 return -E_BAD_EXIT_CODE;
723 snapshot_removal_status = HS_SUCCESS;
727 static void handle_post_remove_exit(void)
729 snapshot_removal_status = HS_READY;
732 static int handle_remove_exit(int status)
735 struct snapshot *s = snapshot_currently_being_removed;
738 switch (snapshot_removal_status) {
740 handle_pre_remove_exit(status);
744 ret = handle_rm_exit(status);
746 case HS_POST_RUNNING:
747 handle_post_remove_exit();
753 if (snapshot_removal_status == HS_READY) {
756 snapshot_currently_being_removed = NULL;
762 static int wait_for_remove_process(void)
768 snapshot_removal_status == HS_PRE_RUNNING ||
769 snapshot_removal_status == HS_RUNNING ||
770 snapshot_removal_status == HS_POST_RUNNING
772 ret = wait_for_process(remove_pid, &status);
775 return handle_remove_exit(status);
778 static int handle_rsync_exit(int status)
782 if (!WIFEXITED(status)) {
783 DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)create_pid);
784 ret = -E_INVOLUNTARY_EXIT;
785 snapshot_creation_status = HS_READY;
788 es = WEXITSTATUS(status);
790 * Restart rsync on non-fatal errors:
791 * 12: Error in rsync protocol data stream
792 * 13: Errors with program diagnostics
794 if (es == 12 || es == 13) {
795 DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n",
796 (int)create_pid, es);
797 snapshot_creation_status = HS_NEEDS_RESTART;
798 next_snapshot_time = get_current_time() + 60;
802 if (es != 0 && es != 23 && es != 24) {
803 DSS_ERROR_LOG("rsync process %d returned %d\n", (int)create_pid, es);
804 ret = -E_BAD_EXIT_CODE;
805 snapshot_creation_status = HS_READY;
808 ret = rename_incomplete_snapshot(current_snapshot_creation_time);
811 snapshot_creation_status = HS_SUCCESS;
812 free(name_of_reference_snapshot);
813 name_of_reference_snapshot = NULL;
815 create_process_stopped = 0;
819 static int handle_pre_create_hook_exit(int status)
822 static int warn_count;
824 if (!WIFEXITED(status)) {
825 snapshot_creation_status = HS_READY;
826 ret = -E_INVOLUNTARY_EXIT;
829 es = WEXITSTATUS(status);
832 DSS_NOTICE_LOG("pre_create_hook %s returned %d\n",
833 conf.pre_create_hook_arg, es);
834 DSS_NOTICE_LOG("deferring snapshot creation...\n");
835 warn_count = 60; /* warn only once per hour */
837 next_snapshot_time = get_current_time() + 60;
838 snapshot_creation_status = HS_READY;
843 snapshot_creation_status = HS_PRE_SUCCESS;
849 static int handle_sigchld(void)
852 int status, ret = reap_child(&pid, &status);
857 if (pid == create_pid) {
858 switch (snapshot_creation_status) {
860 ret = handle_pre_create_hook_exit(status);
863 ret = handle_rsync_exit(status);
865 case HS_POST_RUNNING:
866 snapshot_creation_status = HS_READY;
870 DSS_EMERG_LOG("BUG: create can't die in status %d\n",
871 snapshot_creation_status);
877 if (pid == remove_pid) {
878 ret = handle_remove_exit(status);
883 DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid);
887 static int check_config(void)
889 if (conf.unit_interval_arg <= 0) {
890 DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg);
891 return -E_INVALID_NUMBER;
893 DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg);
894 if (conf.num_intervals_arg <= 0) {
895 DSS_ERROR_LOG("bad number of intervals %i\n", conf.num_intervals_arg);
896 return -E_INVALID_NUMBER;
898 DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg);
903 * Returns < 0 on errors, 0 if no config file is given and > 0 if the config
904 * file was read successfully.
906 static int parse_config_file(int override)
908 int ret, config_file_exists;
911 char *old_logfile_arg = NULL;
912 int old_daemon_given = 0;
914 if (conf.config_file_given)
915 config_file = dss_strdup(conf.config_file_arg);
917 char *home = get_homedir();
918 config_file = make_message("%s/.dssrc", home);
921 if (override) { /* SIGHUP */
922 if (conf.logfile_given)
923 old_logfile_arg = dss_strdup(conf.logfile_arg);
924 old_daemon_given = conf.daemon_given;
927 config_file_exists = !stat(config_file, &statbuf);
928 if (!config_file_exists && conf.config_file_given) {
929 ret = -ERRNO_TO_DSS_ERROR(errno);
930 DSS_ERROR_LOG("failed to stat config file %s\n", config_file);
933 if (config_file_exists) {
934 struct cmdline_parser_params params = {
935 .override = override,
938 .check_ambiguity = 0,
941 if (override) { /* invalidate all rsync options */
944 for (i = 0; i < conf.rsync_option_given; i++) {
945 free(conf.rsync_option_arg[i]);
946 conf.rsync_option_arg[i] = NULL;
948 conf.rsync_option_given = 0;
950 cmdline_parser_config_file(config_file, &conf, ¶ms);
952 ret = check_config();
956 /* don't change daemon mode on SIGHUP */
957 conf.daemon_given = old_daemon_given;
960 if (conf.logfile_given)
961 free(old_logfile_arg);
962 else if (conf.daemon_given) { /* re-use old logfile */
963 conf.logfile_arg = old_logfile_arg;
964 conf.logfile_given = 1;
967 if (conf.logfile_given && conf.run_given && conf.daemon_given) {
968 logfile = open_log(conf.logfile_arg);
969 log_welcome(conf.loglevel_arg);
971 DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg);
972 ret = config_file_exists;
976 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
980 static int change_to_dest_dir(void)
982 DSS_INFO_LOG("changing cwd to %s\n", conf.dest_dir_arg);
983 return dss_chdir(conf.dest_dir_arg);
986 static int handle_sighup(void)
990 DSS_NOTICE_LOG("SIGHUP, re-reading config\n");
991 dump_dss_config("old");
992 ret = parse_config_file(1);
995 dump_dss_config("reloaded");
996 invalidate_next_snapshot_time();
997 return change_to_dest_dir();
1000 static int handle_signal(void)
1002 int sig, ret = next_signal();
1010 restart_create_process();
1011 dss_kill(create_pid, SIGTERM, NULL);
1012 dss_kill(remove_pid, SIGTERM, NULL);
1016 ret = handle_sighup();
1019 ret = handle_sigchld();
1024 DSS_ERROR_LOG("%s\n", dss_strerror(-ret));
1029 * We can not use rsync locally if the local user is different from the remote
1030 * user or if the src dir is not on the local host (or both).
1032 static int use_rsync_locally(char *logname)
1034 char *h = conf.remote_host_arg;
1036 if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1"))
1038 if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname))
1043 static int rename_resume_snap(int64_t creation_time)
1045 struct snapshot_list sl = {.num_snapshots = 0};
1046 struct snapshot *s = NULL;
1047 char *new_name = incomplete_name(creation_time);
1052 if (conf.no_resume_given)
1054 dss_get_snapshot_list(&sl);
1056 * Snapshot recycling: We first look at the newest snapshot. If this
1057 * snapshot happens to be incomplete, the last rsync process was
1058 * aborted and we reuse this one. Otherwise we look at snapshots which
1059 * could be removed (outdated and redundant snapshots) as candidates
1060 * for recycling. If no outdated/redundant snapshot exists, we check if
1061 * there is an orphaned snapshot, which likely is useless anyway.
1063 * Only if no existing snapshot is suitable for recycling, we bite the
1064 * bullet and create a new one.
1066 s = get_newest_snapshot(&sl);
1067 if (!s) /* no snapshots at all */
1069 /* re-use last snapshot if it is incomplete */
1071 if ((s->flags & SS_COMPLETE) == 0)
1074 s = find_outdated_snapshot(&sl);
1078 s = find_redundant_snapshot(&sl);
1082 s = find_orphaned_snapshot(&sl);
1085 DSS_INFO_LOG("reusing %s snapshot %s\n", why, s->name);
1086 ret = dss_rename(s->name, new_name);
1089 DSS_NOTICE_LOG("creating new snapshot %s\n", new_name);
1091 free_snapshot_list(&sl);
1095 static void create_rsync_argv(char ***argv, int64_t *num)
1099 struct snapshot_list sl;
1101 dss_get_snapshot_list(&sl);
1102 assert(!name_of_reference_snapshot);
1103 name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
1104 free_snapshot_list(&sl);
1106 *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
1107 (*argv)[i++] = dss_strdup("rsync");
1108 (*argv)[i++] = dss_strdup("-aq");
1109 (*argv)[i++] = dss_strdup("--delete");
1110 for (j = 0; j < conf.rsync_option_given; j++)
1111 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
1112 if (name_of_reference_snapshot) {
1113 DSS_INFO_LOG("using %s as reference\n", name_of_reference_snapshot);
1114 (*argv)[i++] = make_message("--link-dest=../%s",
1115 name_of_reference_snapshot);
1117 DSS_INFO_LOG("no suitable reference snapshot found\n");
1118 logname = dss_logname();
1119 if (use_rsync_locally(logname))
1120 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
1122 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
1123 conf.remote_user_arg : logname,
1124 conf.remote_host_arg, conf.source_dir_arg);
1126 *num = get_current_time();
1127 (*argv)[i++] = incomplete_name(*num);
1128 (*argv)[i++] = NULL;
1129 for (j = 0; j < i; j++)
1130 DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]);
1133 static void free_rsync_argv(char **argv)
1139 for (i = 0; argv[i]; i++)
1144 static int create_snapshot(char **argv)
1146 int ret, fds[3] = {0, 0, 0};
1148 ret = rename_resume_snap(current_snapshot_creation_time);
1151 ret = dss_exec(&create_pid, argv[0], argv, fds);
1154 snapshot_creation_status = HS_RUNNING;
1158 static int select_loop(void)
1161 /* check every 60 seconds for free disk space */
1163 char **rsync_argv = NULL;
1167 struct timeval *tvp;
1170 tvp = NULL; /* sleep until rm hook/process dies */
1171 else { /* sleep one minute */
1177 FD_SET(signal_pipe, &rfds);
1178 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
1181 if (FD_ISSET(signal_pipe, &rfds)) {
1182 ret = handle_signal();
1188 if (snapshot_removal_status == HS_PRE_SUCCESS) {
1194 if (snapshot_removal_status == HS_SUCCESS) {
1195 ret = post_remove_hook();
1200 ret = try_to_free_disk_space();
1203 if (snapshot_removal_status != HS_READY) {
1204 stop_create_process();
1207 restart_create_process();
1208 switch (snapshot_creation_status) {
1210 if (!next_snapshot_is_due())
1212 ret = pre_create_hook();
1216 case HS_PRE_RUNNING:
1218 case HS_POST_RUNNING:
1220 case HS_PRE_SUCCESS:
1221 if (!name_of_reference_snapshot) {
1222 free_rsync_argv(rsync_argv);
1223 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1225 ret = create_snapshot(rsync_argv);
1229 case HS_NEEDS_RESTART:
1230 if (!next_snapshot_is_due())
1232 ret = create_snapshot(rsync_argv);
1237 ret = post_create_hook();
1247 static void exit_hook(int exit_code)
1249 int fds[3] = {0, 0, 0};
1250 char *argv[] = {conf.exit_hook_arg, dss_strerror(-exit_code), NULL};
1253 DSS_NOTICE_LOG("executing %s %s\n", argv[0], argv[1]);
1254 dss_exec(&pid, conf.exit_hook_arg, argv, fds);
1257 static int com_run(void)
1261 if (conf.dry_run_given) {
1262 DSS_ERROR_LOG("dry_run not supported by this command\n");
1265 ret = install_sighandler(SIGHUP);
1268 ret = select_loop();
1269 if (ret >= 0) /* impossible */
1275 static int com_prune(void)
1278 struct snapshot_list sl;
1279 struct snapshot *victim;
1280 struct disk_space ds;
1283 ret = get_disk_space(".", &ds);
1286 log_disk_space(&ds);
1287 dss_get_snapshot_list(&sl);
1289 victim = find_outdated_snapshot(&sl);
1293 victim = find_redundant_snapshot(&sl);
1299 if (conf.dry_run_given) {
1300 dss_msg("%s snapshot %s (interval = %i)\n",
1301 why, victim->name, victim->interval);
1305 ret = pre_remove_hook(victim, why);
1308 if (snapshot_removal_status == HS_PRE_RUNNING) {
1309 ret = wait_for_remove_process();
1312 if (snapshot_removal_status != HS_PRE_SUCCESS)
1318 ret = wait_for_remove_process();
1321 if (snapshot_removal_status != HS_SUCCESS)
1323 ret = post_remove_hook();
1326 if (snapshot_removal_status != HS_POST_RUNNING)
1328 ret = wait_for_remove_process();
1333 free_snapshot_list(&sl);
1337 static int com_create(void)
1342 if (conf.dry_run_given) {
1345 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1346 for (i = 0; rsync_argv[i]; i++) {
1348 msg = make_message("%s%s%s", tmp? tmp : "",
1349 tmp? " " : "", rsync_argv[i]);
1352 free_rsync_argv(rsync_argv);
1353 dss_msg("%s\n", msg);
1357 ret = pre_create_hook();
1361 ret = wait_for_process(create_pid, &status);
1364 ret = handle_pre_create_hook_exit(status);
1365 if (ret <= 0) /* error, or pre-create failed */
1368 create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
1369 ret = create_snapshot(rsync_argv);
1372 ret = wait_for_process(create_pid, &status);
1375 ret = handle_rsync_exit(status);
1380 ret = wait_for_process(create_pid, &status);
1382 free_rsync_argv(rsync_argv);
1386 static int com_ls(void)
1389 struct snapshot_list sl;
1392 dss_get_snapshot_list(&sl);
1393 FOR_EACH_SNAPSHOT(s, i, &sl) {
1395 if (s->flags & SS_COMPLETE)
1396 d = (s->completion_time - s->creation_time) / 60;
1397 dss_msg("%u\t%s\t%3" PRId64 ":%02" PRId64 "\n", s->interval, s->name, d/60, d%60);
1399 free_snapshot_list(&sl);
1403 static int setup_signal_handling(void)
1407 DSS_INFO_LOG("setting up signal handlers\n");
1408 signal_pipe = signal_init(); /* always successful */
1409 ret = install_sighandler(SIGINT);
1412 ret = install_sighandler(SIGTERM);
1415 return install_sighandler(SIGCHLD);
1419 * The main function of dss.
1421 * \param argc Usual argument count.
1422 * \param argv Usual argument vector.
1424 int main(int argc, char **argv)
1427 struct cmdline_parser_params params = {
1430 .check_required = 0,
1431 .check_ambiguity = 0,
1435 cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */
1436 ret = parse_config_file(0);
1439 if (ret == 0) { /* no config file given */
1441 * Parse the command line options again, but this time check
1442 * that all required options are given.
1444 params = (struct cmdline_parser_params) {
1447 .check_required = 1,
1448 .check_ambiguity = 1,
1451 cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */
1453 if (conf.daemon_given)
1455 ret = change_to_dest_dir();
1458 dump_dss_config("startup");
1459 ret = setup_signal_handling();
1462 ret = call_command_handler();
1465 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
1466 exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);