X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=c5f636c2ed8b86ad5170c164d3f6e2d4d08d862c;hp=0083e2ecae86310a679f201a81d408f3d1c882a4;hb=67f36528afce8e7dd5016283eb3da5a99be4778d;hpb=00e72666c12061e55c020a706448fac5497ce940 diff --git a/dss.c b/dss.c index 0083e2e..c5f636c 100644 --- a/dss.c +++ b/dss.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2008 Andre Noll + * Copyright (C) 2008-2009 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -40,24 +40,27 @@ static struct gengetopt_args_info conf; static FILE *logfile; /** The read end of the signal pipe */ static int signal_pipe; -/** Process id of current rsync process. */ -static pid_t rsync_pid; -/** Whether the rsync process is currently stopped */ -static int rsync_stopped; -/** Process id of current rm process. */ -static pid_t rm_pid; +/** Process id of current pre-create-hook/rsync/post-create-hook process. */ +static pid_t create_pid; +/** Whether the pre-create-hook/rsync/post-create-hook is currently stopped. */ +static int create_process_stopped; +/** Process id of current pre-remove/rm/post-remove process. */ +static pid_t remove_pid; /** When the next snapshot is due. */ -static struct timeval next_snapshot_time; -/** The pid of the pre-create hook. */ -static pid_t pre_create_hook_pid; -/** The pid of the post-create hook. */ -static pid_t post_create_hook_pid; +static int64_t next_snapshot_time; +/** When to try to remove something. */ +static struct timeval next_removal_check; /** Creation time of the snapshot currently being created. */ static int64_t current_snapshot_creation_time; +/** The snapshot currently being removed. */ +struct snapshot *snapshot_currently_being_removed; /** Needed by the post-create hook. */ static char *path_to_last_complete_snapshot; +static char *name_of_reference_snapshot; /** \sa \ref snap.h for details. */ -static unsigned snapshot_creation_status; +enum hook_status snapshot_creation_status; +/** \sa \ref snap.h for details. */ +enum hook_status snapshot_removal_status; DEFINE_DSS_ERRLIST; @@ -77,7 +80,7 @@ static int call_command_handler(void) { COMMANDS DSS_EMERG_LOG("BUG: did not find command handler\n"); - exit(EXIT_FAILURE); + return -E_BUG; } #undef COMMAND #undef COMMANDS @@ -124,7 +127,6 @@ static __printf_1_2 void dss_msg(const char* fmt,...) va_end(argp); } -/* TODO: Also consider number of inodes. */ static int disk_space_low(void) { struct disk_space ds; @@ -149,18 +151,16 @@ static void dss_get_snapshot_list(struct snapshot_list *sl) get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg); } -static void compute_next_snapshot_time(void) +static int64_t compute_next_snapshot_time(void) { - struct timeval now, unit_interval = {.tv_sec = 24 * 3600 * conf.unit_interval_arg}, - tmp, diff; - int64_t x = 0; + int64_t x = 0, now = get_current_time(), unit_interval + = 24 * 3600 * conf.unit_interval_arg, ret; unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg), num_complete_snapshots = 0; - int i, ret; + int i; struct snapshot *s = NULL; struct snapshot_list sl; - assert(snapshot_creation_status == SCS_READY); current_snapshot_creation_time = 0; dss_get_snapshot_list(&sl); FOR_EACH_SNAPSHOT(s, i, &sl) { @@ -170,52 +170,173 @@ static void compute_next_snapshot_time(void) x += s->completion_time - s->creation_time; } assert(x >= 0); - if (num_complete_snapshots) - x /= num_complete_snapshots; /* avg time to create one snapshot */ - x *= wanted; /* time to create all snapshots in interval 0 */ - tmp.tv_sec = x; - tmp.tv_usec = 0; - ret = tv_diff(&unit_interval, &tmp, &diff); /* total sleep time per unit interval */ - gettimeofday(&now, NULL); - if (ret < 0 || !s) - goto min_sleep; - tv_divide(wanted, &diff, &tmp); /* sleep time betweeen two snapshots */ - diff.tv_sec = s->completion_time; - diff.tv_usec = 0; - tv_add(&diff, &tmp, &next_snapshot_time); - if (tv_diff(&now, &next_snapshot_time, NULL) < 0) + + ret = now; + if (num_complete_snapshots == 0) + goto out; + x /= num_complete_snapshots; /* avg time to create one snapshot */ + if (unit_interval < x * wanted) /* oops, no sleep at all */ goto out; -min_sleep: - next_snapshot_time = now; - next_snapshot_time.tv_sec += 60; + ret = s->completion_time + unit_interval / wanted - x; out: free_snapshot_list(&sl); + return ret; +} + +static inline void invalidate_next_snapshot_time(void) +{ + next_snapshot_time = 0; } +static inline int next_snapshot_time_is_valid(void) +{ + return next_snapshot_time != 0; +} + +static int next_snapshot_is_due(void) +{ + int64_t now = get_current_time(); + + assert(snapshot_creation_status == HS_READY); + if (!next_snapshot_time_is_valid()) + next_snapshot_time = compute_next_snapshot_time(); + if (next_snapshot_time <= now) { + DSS_DEBUG_LOG("next snapshot: now\n"); + return 1; + } + DSS_DEBUG_LOG("next snapshot due in %" PRId64 " seconds\n", + next_snapshot_time - now); + return 0; +} + +static int pre_create_hook(void) +{ + int ret, fds[3] = {0, 0, 0}; + + assert(snapshot_creation_status == HS_READY); + /* make sure that the next snapshot time will be recomputed */ + invalidate_next_snapshot_time(); + if (!conf.pre_create_hook_given) { + snapshot_creation_status = HS_PRE_SUCCESS; + return 0; + } + DSS_DEBUG_LOG("executing %s\n", conf.pre_create_hook_arg); + ret = dss_exec_cmdline_pid(&create_pid, + conf.pre_create_hook_arg, fds); + if (ret < 0) + return ret; + snapshot_creation_status = HS_PRE_RUNNING; + return ret; +} + +static int pre_remove_hook(struct snapshot *s, const char *why) +{ + int ret, fds[3] = {0, 0, 0}; + char *cmd; + + if (!s) + return 0; + DSS_DEBUG_LOG("%s snapshot %s\n", why, s->name); + assert(snapshot_removal_status == HS_READY); + assert(remove_pid == 0); + assert(!snapshot_currently_being_removed); + + snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot)); + *snapshot_currently_being_removed = *s; + snapshot_currently_being_removed->name = dss_strdup(s->name); -static int remove_snapshot(struct snapshot *s) + if (!conf.pre_remove_hook_given) { + snapshot_removal_status = HS_PRE_SUCCESS; + return 0; + } + cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg, + conf.dest_dir_arg, s->name); + DSS_DEBUG_LOG("executing %s\n", cmd); + ret = dss_exec_cmdline_pid(&remove_pid, + conf.pre_remove_hook_arg, fds); + free(cmd); + if (ret < 0) + return ret; + snapshot_removal_status = HS_PRE_RUNNING; + return ret; +} + +static int exec_rm(void) { + struct snapshot *s = snapshot_currently_being_removed; int fds[3] = {0, 0, 0}; - assert(!rm_pid); char *new_name = being_deleted_name(s); - int ret = dss_rename(s->name, new_name); char *argv[] = {"rm", "-rf", new_name, NULL}; + int ret; + + assert(snapshot_removal_status == HS_PRE_SUCCESS); + assert(remove_pid == 0); + DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval); + ret = dss_rename(s->name, new_name); if (ret < 0) goto out; - DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval); - ret = dss_exec(&rm_pid, argv[0], argv, fds); + ret = dss_exec(&remove_pid, argv[0], argv, fds); + if (ret < 0) + goto out; + snapshot_removal_status = HS_RUNNING; out: free(new_name); return ret; } +static int snapshot_is_being_created(struct snapshot *s) +{ + return s->creation_time == current_snapshot_creation_time; +} + +static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl) +{ + struct snapshot *s; + int i; + + DSS_DEBUG_LOG("looking for orphaned snapshots\n"); + FOR_EACH_SNAPSHOT(s, i, sl) { + if (snapshot_is_being_created(s)) + continue; + /* + * We know that no rm is currently running, so if s is marked + * as being deleted, a previously started rm must have failed. + */ + if (s->flags & SS_BEING_DELETED) + return s; + + if (s->flags & SS_COMPLETE) /* good snapshot */ + continue; + /* + * This snapshot is incomplete and it is not the snapshot + * currently being created. However, we must not remove it if + * rsync is about to be restarted. As only the newest snapshot + * can be restarted, this snapshot is orphaned if it is not the + * newest snapshot or if we are not about to restart rsync. + */ + if (get_newest_snapshot(sl) != s) + return s; + if (snapshot_creation_status != HS_NEEDS_RESTART) + return s; + } + /* no orphaned snapshots */ + return NULL; +} + +static int is_reference_snapshot(struct snapshot *s) +{ + if (!name_of_reference_snapshot) + return 0; + return strcmp(s->name, name_of_reference_snapshot)? 0 : 1; +} + /* * return: 0: no redundant snapshots, 1: rm process started, negative: error */ -static int remove_redundant_snapshot(struct snapshot_list *sl) +static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) { - int ret, i, interval; + int i, interval; struct snapshot *s; unsigned missing = 0; @@ -236,6 +357,10 @@ static int remove_redundant_snapshot(struct snapshot_list *sl) FOR_EACH_SNAPSHOT(s, i, sl) { int64_t this_score; + if (snapshot_is_being_created(s)) + continue; + if (is_reference_snapshot(s)) + continue; //DSS_DEBUG_LOG("checking %s\n", s->name); if (s->interval > interval) { prev = s; @@ -260,50 +385,43 @@ static int remove_redundant_snapshot(struct snapshot_list *sl) prev = s; } assert(victim); - if (conf.dry_run_given) { - dss_msg("%s would be removed (interval = %i)\n", - victim->name, victim->interval); - continue; - } - ret = remove_snapshot(victim); - return ret < 0? ret : 1; + return victim; } - return 0; + return NULL; } -static int remove_outdated_snapshot(struct snapshot_list *sl) +static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl) { - int i, ret; + int i; struct snapshot *s; - DSS_DEBUG_LOG("looking for snapshots belonging to intervals greater than %d\n", + DSS_DEBUG_LOG("looking for snapshots belonging to intervals >= %d\n", conf.num_intervals_arg); FOR_EACH_SNAPSHOT(s, i, sl) { - if (s->interval <= conf.num_intervals_arg) + if (snapshot_is_being_created(s)) continue; - if (conf.dry_run_given) { - dss_msg("%s would be removed (interval = %i)\n", - s->name, s->interval); + if (is_reference_snapshot(s)) continue; - } - ret = remove_snapshot(s); - if (ret < 0) - return ret; - return 1; + if (s->interval < conf.num_intervals_arg) + continue; + return s; } - return 0; + return NULL; } -static int remove_oldest_snapshot(struct snapshot_list *sl) +struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl) { - struct snapshot *s = get_oldest_snapshot(sl); - - if (!s) /* no snapshot found */ - return 0; - DSS_INFO_LOG("oldest snapshot: %s\n", s->name); - if (s->creation_time == current_snapshot_creation_time) - return 0; /* do not remove the snapshot currently being created */ - return remove_snapshot(s); + int i; + struct snapshot *s; + FOR_EACH_SNAPSHOT(s, i, sl) { + if (snapshot_is_being_created(s)) + continue; + if (is_reference_snapshot(s)) + continue; + DSS_INFO_LOG("oldest removable snapshot: %s\n", s->name); + return s; + } + return NULL; } static int rename_incomplete_snapshot(int64_t start) @@ -325,68 +443,103 @@ static int rename_incomplete_snapshot(int64_t start) return ret; } -static int try_to_free_disk_space(int low_disk_space) +static int try_to_free_disk_space(void) { int ret; struct snapshot_list sl; + struct snapshot *victim; + struct timeval now; + const char *why; + int low_disk_space; + ret = disk_space_low(); + if (ret < 0) + return ret; + low_disk_space = ret; + gettimeofday(&now, NULL); + if (tv_diff(&next_removal_check, &now, NULL) > 0) + return 0; + if (!low_disk_space) { + if (conf.keep_redundant_given) + return 0; + if (snapshot_creation_status != HS_READY) + return 0; + if (next_snapshot_is_due()) + return 0; + } dss_get_snapshot_list(&sl); - ret = remove_outdated_snapshot(&sl); - if (ret) /* error, or we are removing something */ - goto out; - /* no outdated snapshot */ - ret = remove_redundant_snapshot(&sl); - if (ret) - goto out; ret = 0; + if (!low_disk_space && sl.num_snapshots <= 1) + goto out; + why = "outdated"; + victim = find_outdated_snapshot(&sl); + if (victim) + goto remove; + why = "redundant"; + victim = find_redundant_snapshot(&sl); + if (victim) + goto remove; + /* try harder only if disk space is low */ if (!low_disk_space) goto out; + why = "orphaned"; + victim = find_orphaned_snapshot(&sl); + if (victim) + goto remove; DSS_WARNING_LOG("disk space low and nothing obvious to remove\n"); - ret = remove_oldest_snapshot(&sl); - if (ret) - goto out; - DSS_CRIT_LOG("uhuhu: not enough disk space for a single snapshot\n"); + victim = find_oldest_removable_snapshot(&sl); + if (victim) + goto remove; + DSS_CRIT_LOG("uhuhu: disk space low and nothing to remove\n"); ret = -ERRNO_TO_DSS_ERROR(ENOSPC); + goto out; +remove: + ret = pre_remove_hook(victim, why); out: free_snapshot_list(&sl); return ret; } -static int pre_create_hook(void) +static int post_create_hook(void) { int ret, fds[3] = {0, 0, 0}; + char *cmd; - if (!conf.pre_create_hook_given) { - snapshot_creation_status = SCS_PRE_HOOK_SUCCESS; + if (!conf.post_create_hook_given) { + snapshot_creation_status = HS_READY; return 0; } - DSS_NOTICE_LOG("executing %s\n", conf.pre_create_hook_arg); - ret = dss_exec_cmdline_pid(&pre_create_hook_pid, - conf.pre_create_hook_arg, fds); + cmd = make_message("%s %s/%s", conf.post_create_hook_arg, + conf.dest_dir_arg, path_to_last_complete_snapshot); + DSS_NOTICE_LOG("executing %s\n", cmd); + ret = dss_exec_cmdline_pid(&create_pid, cmd, fds); + free(cmd); if (ret < 0) return ret; - snapshot_creation_status = SCS_PRE_HOOK_RUNNING; + snapshot_creation_status = HS_POST_RUNNING; return ret; } -static int post_create_hook(void) +static int post_remove_hook(void) { int ret, fds[3] = {0, 0, 0}; char *cmd; + struct snapshot *s = snapshot_currently_being_removed; - if (!conf.post_create_hook_given) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); + assert(s); + + if (!conf.post_remove_hook_given) { + snapshot_removal_status = HS_READY; return 0; } - cmd = make_message("%s %s", conf.post_create_hook_arg, - path_to_last_complete_snapshot); + cmd = make_message("%s %s/%s", conf.post_remove_hook_arg, + conf.dest_dir_arg, s->name); DSS_NOTICE_LOG("executing %s\n", cmd); - ret = dss_exec_cmdline_pid(&post_create_hook_pid, cmd, fds); + ret = dss_exec_cmdline_pid(&remove_pid, cmd, fds); free(cmd); if (ret < 0) return ret; - snapshot_creation_status = SCS_POST_HOOK_RUNNING; + snapshot_removal_status = HS_POST_RUNNING; return ret; } @@ -398,23 +551,22 @@ static void kill_process(pid_t pid) kill(pid, SIGTERM); } -static void stop_rsync_process(void) +static void stop_create_process(void) { - if (!rsync_pid || rsync_stopped) + if (!create_pid || create_process_stopped) return; - kill(SIGSTOP, rsync_pid); - rsync_stopped = 1; + kill(SIGSTOP, create_pid); + create_process_stopped = 1; } -static void restart_rsync_process(void) +static void restart_create_process(void) { - if (!rsync_pid || !rsync_stopped) + if (!create_pid || !create_process_stopped) return; - kill (SIGCONT, rsync_pid); - rsync_stopped = 0; + kill (SIGCONT, create_pid); + create_process_stopped = 0; } - /** * Print a log message about the exit status of a child. */ @@ -466,23 +618,83 @@ static int wait_for_process(pid_t pid, int *status) return ret; } +static void handle_pre_remove_exit(int status) +{ + if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { + snapshot_removal_status = HS_READY; + gettimeofday(&next_removal_check, NULL); + next_removal_check.tv_sec += 60; + return; + } + snapshot_removal_status = HS_PRE_SUCCESS; +} + static int handle_rm_exit(int status) { - rm_pid = 0; - if (!WIFEXITED(status)) + if (!WIFEXITED(status)) { + snapshot_removal_status = HS_READY; return -E_INVOLUNTARY_EXIT; - if (WEXITSTATUS(status)) + } + if (WEXITSTATUS(status)) { + snapshot_removal_status = HS_READY; return -E_BAD_EXIT_CODE; + } + if (conf.post_remove_hook_given) + snapshot_removal_status = HS_SUCCESS; + else + snapshot_removal_status = HS_READY; return 1; } -static int wait_for_rm_process(void) +static void handle_post_remove_exit(void) +{ + snapshot_removal_status = HS_READY; +} + +static int handle_remove_exit(int status) { - int status, ret = wait_for_process(rm_pid, &status); + int ret; + struct snapshot *s = snapshot_currently_being_removed; + + assert(s); + switch (snapshot_removal_status) { + case HS_PRE_RUNNING: + handle_pre_remove_exit(status); + ret = 1; + break; + case HS_RUNNING: + ret = handle_rm_exit(status); + break; + case HS_POST_RUNNING: + handle_post_remove_exit(); + ret = 1; + break; + default: + ret = -E_BUG; + } + if (snapshot_removal_status == HS_READY) { + free(s->name); + free(s); + snapshot_currently_being_removed = NULL; + } + remove_pid = 0; + return ret; +} +static int wait_for_remove_process(void) +{ + int status, ret; + + assert(remove_pid); + assert( + snapshot_removal_status == HS_PRE_RUNNING || + snapshot_removal_status == HS_RUNNING || + snapshot_removal_status == HS_POST_RUNNING + ); + ret = wait_for_process(remove_pid, &status); if (ret < 0) return ret; - return handle_rm_exit(status); + return handle_remove_exit(status); } static int handle_rsync_exit(int status) @@ -490,51 +702,71 @@ static int handle_rsync_exit(int status) int es, ret; if (!WIFEXITED(status)) { - DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)rsync_pid); + DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)create_pid); ret = -E_INVOLUNTARY_EXIT; - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); + snapshot_creation_status = HS_READY; goto out; } es = WEXITSTATUS(status); + /* + * Restart rsync on non-fatal errors: + * 12: Error in rsync protocol data stream + * 13: Errors with program diagnostics + */ + if (es == 12 || es == 13) { + DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n", + (int)create_pid, es); + snapshot_creation_status = HS_NEEDS_RESTART; + next_snapshot_time = get_current_time() + 60; + ret = 1; + goto out; + } if (es != 0 && es != 23 && es != 24) { - DSS_ERROR_LOG("rsync process %d returned %d\n", (int)rsync_pid, es); + DSS_ERROR_LOG("rsync process %d returned %d\n", (int)create_pid, es); ret = -E_BAD_EXIT_CODE; - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); + snapshot_creation_status = HS_READY; goto out; } ret = rename_incomplete_snapshot(current_snapshot_creation_time); if (ret < 0) goto out; - snapshot_creation_status = SCS_RSYNC_SUCCESS; + snapshot_creation_status = HS_SUCCESS; + free(name_of_reference_snapshot); + name_of_reference_snapshot = NULL; out: - rsync_pid = 0; - rsync_stopped = 0; + create_pid = 0; + create_process_stopped = 0; return ret; } static int handle_pre_create_hook_exit(int status) { int es, ret; + static int warn_count; if (!WIFEXITED(status)) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); + snapshot_creation_status = HS_READY; ret = -E_INVOLUNTARY_EXIT; goto out; } es = WEXITSTATUS(status); if (es) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); - ret = -E_BAD_EXIT_CODE; + if (!warn_count--) { + DSS_NOTICE_LOG("pre_create_hook %s returned %d\n", + conf.pre_create_hook_arg, es); + DSS_NOTICE_LOG("deferring snapshot creation...\n"); + warn_count = 60; /* warn only once per hour */ + } + next_snapshot_time = get_current_time() + 60; + snapshot_creation_status = HS_READY; + ret = 0; goto out; } - snapshot_creation_status = SCS_PRE_HOOK_SUCCESS; + warn_count = 0; + snapshot_creation_status = HS_PRE_SUCCESS; ret = 1; out: - pre_create_hook_pid = 0; + create_pid = 0; return ret; } @@ -545,19 +777,30 @@ static int handle_sigchld(void) if (ret <= 0) return ret; - if (pid == rsync_pid) - return handle_rsync_exit(status); - if (pid == rm_pid) - return handle_rm_exit(status); - if (pid == pre_create_hook_pid) - return handle_pre_create_hook_exit(status); - if (pid == post_create_hook_pid) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); - return 1; + + if (pid == create_pid) { + switch (snapshot_creation_status) { + case HS_PRE_RUNNING: + return handle_pre_create_hook_exit(status); + case HS_RUNNING: + return handle_rsync_exit(status); + case HS_POST_RUNNING: + snapshot_creation_status = HS_READY; + return 1; + default: + DSS_EMERG_LOG("BUG: create can't die in status %d\n", + snapshot_creation_status); + return -E_BUG; + } + } + if (pid == remove_pid) { + ret = handle_remove_exit(status); + if (ret < 0) + return ret; + return ret; } DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid); - exit(EXIT_FAILURE); + return -E_BUG; } static int check_config(void) @@ -575,10 +818,13 @@ static int check_config(void) return 1; } -/* exits on errors */ -static void parse_config_file(int override) +/* + * Returns < 0 on errors, 0 if no config file is given and > 0 if the config + * file was read successfully. + */ +static int parse_config_file(int override) { - int ret; + int ret, config_file_exists; char *config_file; struct stat statbuf; char *old_logfile_arg = NULL; @@ -597,13 +843,13 @@ static void parse_config_file(int override) old_daemon_given = conf.daemon_given; } - ret = stat(config_file, &statbuf); - if (ret && conf.config_file_given) { + config_file_exists = !stat(config_file, &statbuf); + if (!config_file_exists && conf.config_file_given) { ret = -ERRNO_TO_DSS_ERROR(errno); DSS_ERROR_LOG("failed to stat config file %s\n", config_file); goto out; } - if (!ret) { + if (config_file_exists) { struct cmdline_parser_params params = { .override = override, .initialize = 0, @@ -611,6 +857,15 @@ static void parse_config_file(int override) .check_ambiguity = 0, .print_errors = 1 }; + if (override) { /* invalidate all rsync options */ + int i; + + for (i = 0; i < conf.rsync_option_given; i++) { + free(conf.rsync_option_arg[i]); + conf.rsync_option_arg[i] = NULL; + } + conf.rsync_option_given = 0; + } cmdline_parser_config_file(config_file, &conf, ¶ms); } ret = check_config(); @@ -632,36 +887,44 @@ static void parse_config_file(int override) logfile = open_log(conf.logfile_arg); log_welcome(conf.loglevel_arg); } - DSS_EMERG_LOG("loglevel: %d\n", conf.loglevel_arg); -// cmdline_parser_dump(logfile? logfile : stdout, &conf); + DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg); + ret = config_file_exists; out: free(config_file); - if (ret >= 0) - return; - DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); - exit(EXIT_FAILURE); + if (ret < 0) + DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); + return ret; } -static void change_to_dest_dir(void) +static int change_to_dest_dir(void) { - int ret; - DSS_INFO_LOG("changing cwd to %s\n", conf.dest_dir_arg); - ret = dss_chdir(conf.dest_dir_arg); - if (ret >= 0) + return dss_chdir(conf.dest_dir_arg); +} + +static void dump_dss_config(const char *msg) +{ + if (conf.loglevel_arg > INFO) return; - DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); - exit(EXIT_FAILURE); + DSS_INFO_LOG("%s\n", msg); + cmdline_parser_dump(logfile? logfile : stderr, &conf); } -static void handle_sighup(void) +static int handle_sighup(void) { - DSS_NOTICE_LOG("SIGHUP\n"); - parse_config_file(1); - change_to_dest_dir(); + int ret; + + DSS_NOTICE_LOG("SIGHUP, re-reading config\n"); + dump_dss_config("current config"); + ret = parse_config_file(1); + if (ret < 0) + return ret; + dump_dss_config("new config"); + invalidate_next_snapshot_time(); + return change_to_dest_dir(); } -static void handle_signal(void) +static int handle_signal(void) { int sig, ret = next_signal(); @@ -671,13 +934,13 @@ static void handle_signal(void) switch (sig) { case SIGINT: case SIGTERM: - restart_rsync_process(); - kill_process(rsync_pid); - kill_process(rm_pid); - exit(EXIT_FAILURE); + restart_create_process(); + kill_process(create_pid); + kill_process(remove_pid); + ret = -E_SIGNAL; + break; case SIGHUP: - handle_sighup(); - ret = 1; + ret = handle_sighup(); break; case SIGCHLD: ret = handle_sigchld(); @@ -686,16 +949,33 @@ static void handle_signal(void) out: if (ret < 0) DSS_ERROR_LOG("%s\n", dss_strerror(-ret)); + return ret; +} + +/* + * We can not use rsync locally if the local user is different from the remote + * user or if the src dir is not on the local host (or both). + */ +static int use_rsync_locally(char *logname) +{ + char *h = conf.remote_host_arg; + + if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1")) + return 0; + if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname)) + return 0; + return 1; } static void create_rsync_argv(char ***argv, int64_t *num) { - char *logname, *newest; + char *logname; int i = 0, j; struct snapshot_list sl; dss_get_snapshot_list(&sl); - newest = name_of_newest_complete_snapshot(&sl); + assert(!name_of_reference_snapshot); + name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl); free_snapshot_list(&sl); *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *)); @@ -704,14 +984,14 @@ static void create_rsync_argv(char ***argv, int64_t *num) (*argv)[i++] = dss_strdup("--delete"); for (j = 0; j < conf.rsync_option_given; j++) (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]); - if (newest) { - DSS_INFO_LOG("using %s as reference snapshot\n", newest); - (*argv)[i++] = make_message("--link-dest=../%s", newest); - free(newest); + if (name_of_reference_snapshot) { + DSS_INFO_LOG("using %s as reference\n", name_of_reference_snapshot); + (*argv)[i++] = make_message("--link-dest=../%s", + name_of_reference_snapshot); } else - DSS_INFO_LOG("no previous snapshot found\n"); + DSS_INFO_LOG("no suitable reference snapshot found\n"); logname = dss_logname(); - if (conf.remote_user_given && !strcmp(conf.remote_user_arg, logname)) + if (use_rsync_locally(logname)) (*argv)[i++] = dss_strdup(conf.source_dir_arg); else (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given? @@ -728,6 +1008,9 @@ static void create_rsync_argv(char ***argv, int64_t *num) static void free_rsync_argv(char **argv) { int i; + + if (!argv) + return; for (i = 0; argv[i]; i++) free(argv[i]); free(argv); @@ -741,10 +1024,10 @@ static int create_snapshot(char **argv) name = incomplete_name(current_snapshot_creation_time); DSS_NOTICE_LOG("creating new snapshot %s\n", name); free(name); - ret = dss_exec(&rsync_pid, argv[0], argv, fds); + ret = dss_exec(&create_pid, argv[0], argv, fds); if (ret < 0) return ret; - snapshot_creation_status = SCS_RSYNC_RUNNING; + snapshot_creation_status = HS_RUNNING; return ret; } @@ -753,15 +1036,14 @@ static int select_loop(void) int ret; /* check every 60 seconds for free disk space */ struct timeval tv; + char **rsync_argv = NULL; for (;;) { fd_set rfds; - int low_disk_space; - char **rsync_argv; - struct timeval now, *tvp; + struct timeval *tvp; - if (rm_pid) - tvp = NULL; /* sleep until rm process dies */ + if (remove_pid) + tvp = NULL; /* sleep until rm hook/process dies */ else { /* sleep one minute */ tv.tv_sec = 60; tv.tv_usec = 0; @@ -772,56 +1054,78 @@ static int select_loop(void) DSS_DEBUG_LOG("tvp: %p, tv_sec : %lu\n", tvp, (long unsigned) tv.tv_sec); ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp); if (ret < 0) - return ret; - if (FD_ISSET(signal_pipe, &rfds)) - handle_signal(); - if (rm_pid) + goto out; + if (FD_ISSET(signal_pipe, &rfds)) { + ret = handle_signal(); + if (ret < 0) + goto out; + } + if (remove_pid) continue; - ret = disk_space_low(); - if (ret < 0) - break; - low_disk_space = ret; - ret = try_to_free_disk_space(low_disk_space); - if (ret < 0) - break; - if (rm_pid) { - stop_rsync_process(); + if (snapshot_removal_status == HS_PRE_SUCCESS) { + ret = exec_rm(); + if (ret < 0) + goto out; + continue; + } + if (snapshot_removal_status == HS_SUCCESS) { + ret = post_remove_hook(); + if (ret < 0) + goto out; continue; } - restart_rsync_process(); - gettimeofday(&now, NULL); - if (tv_diff(&next_snapshot_time, &now, NULL) > 0) + ret = try_to_free_disk_space(); + if (ret < 0) + goto out; + if (snapshot_removal_status != HS_READY) { + stop_create_process(); continue; + } + restart_create_process(); switch (snapshot_creation_status) { - case SCS_READY: + case HS_READY: + if (!next_snapshot_is_due()) + continue; ret = pre_create_hook(); if (ret < 0) goto out; continue; - case SCS_PRE_HOOK_RUNNING: + case HS_PRE_RUNNING: + case HS_RUNNING: + case HS_POST_RUNNING: continue; - case SCS_PRE_HOOK_SUCCESS: + case HS_PRE_SUCCESS: + free_rsync_argv(rsync_argv); create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); + /* fall through */ + case HS_NEEDS_RESTART: ret = create_snapshot(rsync_argv); - free_rsync_argv(rsync_argv); if (ret < 0) goto out; continue; - case SCS_RSYNC_RUNNING: - continue; - case SCS_RSYNC_SUCCESS: + case HS_SUCCESS: ret = post_create_hook(); if (ret < 0) goto out; continue; - case SCS_POST_HOOK_RUNNING: - continue; } } out: return ret; } +static void exit_hook(int exit_code) +{ + int fds[3] = {0, 0, 0}; + char *argv[] = {conf.exit_hook_arg, dss_strerror(-exit_code), NULL}; + pid_t pid; + + if (!conf.exit_hook_given) + return; + DSS_NOTICE_LOG("executing %s %s\n", argv[0], argv[1]); + dss_exec(&pid, conf.exit_hook_arg, argv, fds); +} + static int com_run(void) { int ret; @@ -833,46 +1137,72 @@ static int com_run(void) ret = install_sighandler(SIGHUP); if (ret < 0) return ret; - compute_next_snapshot_time(); - return select_loop(); + ret = select_loop(); + if (ret >= 0) /* impossible */ + ret = -E_BUG; + exit_hook(ret); + return ret; } static int com_prune(void) { int ret; struct snapshot_list sl; + struct snapshot *victim; struct disk_space ds; + const char *why; ret = get_disk_space(".", &ds); if (ret < 0) return ret; log_disk_space(&ds); - for (;;) { - dss_get_snapshot_list(&sl); - ret = remove_outdated_snapshot(&sl); - free_snapshot_list(&sl); - if (ret < 0) - return ret; - if (!ret) - break; - ret = wait_for_rm_process(); - if (ret < 0) - goto out; + dss_get_snapshot_list(&sl); + why = "outdated"; + victim = find_outdated_snapshot(&sl); + if (victim) + goto rm; + why = "redundant"; + victim = find_redundant_snapshot(&sl); + if (victim) + goto rm; + ret = 0; + goto out; +rm: + if (conf.dry_run_given) { + dss_msg("%s snapshot %s (interval = %i)\n", + why, victim->name, victim->interval); + ret = 0; + goto out; } - for (;;) { - dss_get_snapshot_list(&sl); - ret = remove_redundant_snapshot(&sl); - free_snapshot_list(&sl); - if (ret < 0) - return ret; - if (!ret) - break; - ret = wait_for_rm_process(); + ret = pre_remove_hook(victim, why); + if (ret < 0) + goto out; + if (snapshot_removal_status == HS_PRE_RUNNING) { + ret = wait_for_remove_process(); if (ret < 0) goto out; + if (snapshot_removal_status != HS_PRE_SUCCESS) + goto out; } - return 1; + ret = exec_rm(); + if (ret < 0) + goto out; + ret = wait_for_remove_process(); + if (ret < 0) + goto out; + if (snapshot_removal_status != HS_SUCCESS) + goto out; + ret = post_remove_hook(); + if (ret < 0) + goto out; + if (snapshot_removal_status != HS_POST_RUNNING) + goto out; + ret = wait_for_remove_process(); + if (ret < 0) + goto out; + ret = 1; out: + free_snapshot_list(&sl); return ret; } @@ -899,27 +1229,27 @@ static int com_create(void) ret = pre_create_hook(); if (ret < 0) return ret; - if (pre_create_hook_pid) { - ret = wait_for_process(pre_create_hook_pid, &status); + if (create_pid) { + ret = wait_for_process(create_pid, &status); if (ret < 0) return ret; ret = handle_pre_create_hook_exit(status); - if (ret < 0) + if (ret <= 0) /* error, or pre-create failed */ return ret; } create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); ret = create_snapshot(rsync_argv); if (ret < 0) goto out; - ret = wait_for_process(rsync_pid, &status); + ret = wait_for_process(create_pid, &status); if (ret < 0) goto out; ret = handle_rsync_exit(status); if (ret < 0) goto out; post_create_hook(); - if (post_create_hook_pid) - ret = wait_for_process(post_create_hook_pid, &status); + if (create_pid) + ret = wait_for_process(create_pid, &status); out: free_rsync_argv(rsync_argv); return ret; @@ -932,13 +1262,17 @@ static int com_ls(void) struct snapshot *s; dss_get_snapshot_list(&sl); - FOR_EACH_SNAPSHOT(s, i, &sl) - dss_msg("%u\t%s\n", s->interval, s->name); + FOR_EACH_SNAPSHOT(s, i, &sl) { + int64_t d = 0; + if (s->flags & SS_COMPLETE) + d = (s->completion_time - s->creation_time) / 60; + dss_msg("%u\t%s\t%3" PRId64 ":%02" PRId64 "\n", s->interval, s->name, d/60, d%60); + }; free_snapshot_list(&sl); return 1; } -static void setup_signal_handling(void) +static int setup_signal_handling(void) { int ret; @@ -946,17 +1280,11 @@ static void setup_signal_handling(void) signal_pipe = signal_init(); /* always successful */ ret = install_sighandler(SIGINT); if (ret < 0) - goto err; + return ret; ret = install_sighandler(SIGTERM); if (ret < 0) - goto err; - ret = install_sighandler(SIGCHLD); - if (ret < 0) - goto err; - return; -err: - DSS_EMERG_LOG("could not install signal handlers\n"); - exit(EXIT_FAILURE); + return ret; + return install_sighandler(SIGCHLD); } /** @@ -977,13 +1305,34 @@ int main(int argc, char **argv) }; cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */ - parse_config_file(0); - + ret = parse_config_file(0); + if (ret < 0) + goto out; + if (ret == 0) { /* no config file given */ + /* + * Parse the command line options again, but this time check + * that all required options are given. + */ + params = (struct cmdline_parser_params) { + .override = 1, + .initialize = 1, + .check_required = 1, + .check_ambiguity = 1, + .print_errors = 1 + }; + cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */ + } if (conf.daemon_given) daemon_init(); - change_to_dest_dir(); - setup_signal_handling(); + dump_dss_config("dss configuration"); + ret = change_to_dest_dir(); + if (ret < 0) + goto out; + ret = setup_signal_handling(); + if (ret < 0) + goto out; ret = call_command_handler(); +out: if (ret < 0) DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);