X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=03ddaf89c1493c10bef79e7c0f36c9180d2410e5;hp=d7d3e1649d69b849e99cf221ecead9e5a8e61daa;hb=e9e6450e1a8ece2ff879523516fefd6576a76521;hpb=a8e80f1cb5d4c7d4647f50a799e965137b5502a8 diff --git a/dss.c b/dss.c index d7d3e16..03ddaf8 100644 --- a/dss.c +++ b/dss.c @@ -1,16 +1,18 @@ /* - * Copyright (C) 2008-2009 Andre Noll + * Copyright (C) 2008-2011 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ #include #include +#include #include #include #include #include #include #include +#include #include #include #include @@ -24,15 +26,16 @@ #include "gcc-compat.h" #include "cmdline.h" #include "log.h" -#include "string.h" -#include "error.h" -#include "fd.h" +#include "str.h" +#include "err.h" +#include "file.h" #include "exec.h" #include "daemon.h" -#include "signal.h" +#include "sig.h" #include "df.h" -#include "time.h" +#include "tv.h" #include "snap.h" +#include "ipc.h" /** Command line and config file options. */ static struct gengetopt_args_info conf; @@ -44,10 +47,12 @@ static int signal_pipe; static pid_t create_pid; /** Whether the pre-create-hook/rsync/post-create-hook is currently stopped. */ static int create_process_stopped; +/** How many times in a row the rsync command failed. */ +static int num_consecutive_rsync_errors; /** 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; +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. */ @@ -64,14 +69,118 @@ enum hook_status snapshot_removal_status; DEFINE_DSS_ERRLIST; +static const char *hook_status_description[] = {HOOK_STATUS_ARRAY}; +/* may be called with ds == NULL. */ +static int disk_space_low(struct disk_space *ds) +{ + struct disk_space ds_struct; + + if (!ds) { + int ret = get_disk_space(".", &ds_struct); + if (ret < 0) + return ret; + ds = &ds_struct; + } + if (conf.min_free_mb_arg) + if (ds->free_mb < conf.min_free_mb_arg) + return 1; + if (conf.min_free_percent_arg) + if (ds->percent_free < conf.min_free_percent_arg) + return 1; + if (conf.min_free_percent_inodes_arg) + if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg) + return 1; + return 0; +} + +static void dump_dss_config(const char *msg) +{ + const char dash[] = "-----------------------------"; + int ret; + FILE *log = logfile? logfile : stderr; + struct disk_space ds; + int64_t now = get_current_time(); + + if (conf.loglevel_arg > INFO) + return; + + fprintf(log, "%s <%s config> %s\n", dash, msg, dash); + fprintf(log, "\n*** disk space ***\n\n"); + ret = get_disk_space(".", &ds); + if (ret >= 0) { + DSS_INFO_LOG(("disk space low: %s\n", disk_space_low(&ds)? + "yes" : "no")); + log_disk_space(&ds); + } else + DSS_ERROR_LOG(("can not get free disk space: %s\n", + dss_strerror(-ret))); + + /* we continue on errors from get_disk_space */ + + fprintf(log, "\n*** command line and config file options ***\n\n"); + cmdline_parser_dump(log, &conf); + fprintf(log, "\n*** internal state ***\n\n"); + fprintf(log, + "pid: %d\n" + "logile: %s\n" + "snapshot_currently_being_removed: %s\n" + "path_to_last_complete_snapshot: %s\n" + "reference_snapshot: %s\n" + "snapshot_creation_status: %s\n" + "snapshot_removal_status: %s\n" + "num_consecutive_rsync_errors: %d\n" + , + (int) getpid(), + logfile? conf.logfile_arg : "stderr", + snapshot_currently_being_removed? + snapshot_currently_being_removed->name : "(none)", + path_to_last_complete_snapshot? + path_to_last_complete_snapshot : "(none)", + name_of_reference_snapshot? + name_of_reference_snapshot : "(none)", + hook_status_description[snapshot_creation_status], + hook_status_description[snapshot_removal_status], + num_consecutive_rsync_errors + ); + if (create_pid != 0) + fprintf(log, + "create_pid: %" PRId32 "\n" + "create process is %sstopped\n" + , + create_pid, + create_process_stopped? "" : "not " + ); + if (remove_pid != 0) + fprintf(log, "remove_pid: %" PRId32 "\n", remove_pid); + if (next_snapshot_time != 0) + fprintf(log, "next snapshot due in %" PRId64 " seconds\n", + next_snapshot_time - now); + if (current_snapshot_creation_time != 0) + fprintf(log, "current_snapshot_creation_time: %" + PRId64 " (%" PRId64 " seconds ago)\n", + current_snapshot_creation_time, + now - current_snapshot_creation_time + ); + if (next_removal_check.tv_sec != 0) { + fprintf(log, "next removal check: %llu (%llu seconds ago)\n", + (long long unsigned)next_removal_check.tv_sec, + now - (long long unsigned)next_removal_check.tv_sec + ); + + } + fprintf(log, "%s %s\n", dash, msg, dash); +} /* a litte cpp magic helps to DRY */ #define COMMANDS \ COMMAND(ls) \ COMMAND(create) \ COMMAND(prune) \ - COMMAND(run) + COMMAND(run) \ + COMMAND(kill) \ + COMMAND(reload) \ + #define COMMAND(x) static int com_ ##x(void); COMMANDS #undef COMMAND @@ -79,12 +188,25 @@ COMMANDS static int call_command_handler(void) { COMMANDS - DSS_EMERG_LOG("BUG: did not find command handler\n"); + DSS_EMERG_LOG(("BUG: did not find command handler\n")); return -E_BUG; } #undef COMMAND #undef COMMANDS +static int loglevel = -1; +static const char *location_file = NULL; +static int location_line = -1; +static const char *location_func = NULL; + +void dss_log_set_params(int ll, const char *file, int line, const char *func) +{ + loglevel = ll; + location_file = file; + location_line = line; + location_func = func; +} + /** * The log function of dss. * @@ -93,7 +215,7 @@ static int call_command_handler(void) * * All DSS_XXX_LOG() macros use this function. */ -__printf_2_3 void dss_log(int ll, const char* fmt,...) +__printf_1_2 void dss_log(const char* fmt,...) { va_list argp; FILE *outfd; @@ -101,7 +223,7 @@ __printf_2_3 void dss_log(int ll, const char* fmt,...) time_t t1; char str[255] = ""; - if (ll < conf.loglevel_arg) + if (loglevel < conf.loglevel_arg) return; outfd = logfile? logfile : stderr; time(&t1); @@ -109,7 +231,12 @@ __printf_2_3 void dss_log(int ll, const char* fmt,...) strftime(str, sizeof(str), "%b %d %H:%M:%S", tm); fprintf(outfd, "%s ", str); if (conf.loglevel_arg <= INFO) - fprintf(outfd, "%i: ", ll); + fprintf(outfd, "%i: ", loglevel); +#ifdef DSS_NO_FUNC_NAMES + fprintf(outfd, "%s:%d: ", location_file, location_line); +#else + fprintf(outfd, "%s: ", location_func); +#endif va_start(argp, fmt); vfprintf(outfd, fmt, argp); va_end(argp); @@ -127,23 +254,45 @@ static __printf_1_2 void dss_msg(const char* fmt,...) va_end(argp); } -static int disk_space_low(void) +static char *get_config_file_name(void) { - struct disk_space ds; - int ret = get_disk_space(".", &ds); + char *home, *config_file; + + if (conf.config_file_given) + return dss_strdup(conf.config_file_arg); + home = get_homedir(); + config_file = make_message("%s/.dssrc", home); + free(home); + return config_file; +} +static int send_signal(int sig) +{ + pid_t pid; + char *config_file = get_config_file_name(); + int ret = get_dss_pid(config_file, &pid); + + free(config_file); if (ret < 0) return ret; - if (conf.min_free_mb_arg) - if (ds.free_mb < conf.min_free_mb_arg) - return 1; - if (conf.min_free_percent_arg) - if (ds.percent_free < conf.min_free_percent_arg) - return 1; - if (conf.min_free_percent_inodes_arg) - if (ds.percent_free_inodes < conf.min_free_percent_inodes_arg) - return 1; - return 0; + if (conf.dry_run_given) { + dss_msg("%d\n", (int)pid); + return 0; + } + ret = kill(pid, sig); + if (ret < 0) + return -ERRNO_TO_DSS_ERROR(errno); + return 1; +} + +static int com_kill(void) +{ + return send_signal(SIGTERM); +} + +static int com_reload(void) +{ + return send_signal(SIGHUP); } static void dss_get_snapshot_list(struct snapshot_list *sl) @@ -151,82 +300,79 @@ static void dss_get_snapshot_list(struct snapshot_list *sl) get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg); } -static int next_snapshot_is_due(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; + num_complete = 0; + int i; struct snapshot *s = NULL; struct snapshot_list sl; - gettimeofday(&now, NULL); - if (tv_diff(&next_snapshot_time, &now, NULL) > 0) - return 0; - assert(snapshot_creation_status == HS_READY); - current_snapshot_creation_time = 0; dss_get_snapshot_list(&sl); FOR_EACH_SNAPSHOT(s, i, &sl) { if (!(s->flags & SS_COMPLETE)) continue; - num_complete_snapshots++; + num_complete++; 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 */ - if (ret < 0 || !s) { /* unit_interval < tmp or no snapshot */ - ret = 1; - goto out; - } - tv_divide(wanted, &diff, &tmp); /* sleep time between two snapshots */ - diff.tv_sec = s->completion_time; /* completion time of the latest snapshot */ - diff.tv_usec = 0; - tv_add(&diff, &tmp, &next_snapshot_time); - ret = (tv_diff(&now, &next_snapshot_time, &diff) < 0)? 0 : 1; + ret = now; + if (num_complete == 0) + goto out; + x /= num_complete; /* avg time to create one snapshot */ + if (unit_interval < x * wanted) /* oops, no sleep at all */ + goto out; + ret = s->completion_time + unit_interval / wanted - x; out: free_snapshot_list(&sl); - if (ret == 0) - DSS_DEBUG_LOG("next snapshot due in %lu seconds\n", - tv2ms(&diff) / 1000); - else - DSS_DEBUG_LOG("next snapshot: now\n"); return ret; } -static int pre_create_hook(void) +static inline void invalidate_next_snapshot_time(void) { - int ret, fds[3] = {0, 0, 0}; + next_snapshot_time = 0; +} - assert(snapshot_creation_status == HS_READY); - if (!conf.pre_create_hook_given) { - snapshot_creation_status = HS_PRE_SUCCESS; - return 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(); + + 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("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; + DSS_DEBUG_LOG(("next snapshot due in %" PRId64 " seconds\n", + next_snapshot_time - now)); + return 0; +} + +static void pre_create_hook(void) +{ + assert(snapshot_creation_status == HS_READY); + /* make sure that the next snapshot time will be recomputed */ + invalidate_next_snapshot_time(); + DSS_DEBUG_LOG(("executing %s\n", conf.pre_create_hook_arg)); + dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg); snapshot_creation_status = HS_PRE_RUNNING; - return ret; } -static int pre_remove_hook(struct snapshot *s, const char *why) +static void 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); + return; + 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); @@ -235,40 +381,34 @@ static int pre_remove_hook(struct snapshot *s, const char *why) *snapshot_currently_being_removed = *s; snapshot_currently_being_removed->name = dss_strdup(s->name); - 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); + DSS_DEBUG_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&remove_pid, cmd); 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}; char *new_name = being_deleted_name(s); - char *argv[] = {"rm", "-rf", new_name, NULL}; + char *argv[4]; int ret; + argv[0] = "rm"; + argv[1] = "-rf"; + argv[2] = new_name; + argv[3] = NULL; + assert(snapshot_removal_status == HS_PRE_SUCCESS); assert(remove_pid == 0); - DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval); + DSS_NOTICE_LOG(("removing %s (interval = %i)\n", s->name, s->interval)); ret = dss_rename(s->name, new_name); if (ret < 0) goto out; - ret = dss_exec(&remove_pid, argv[0], argv, fds); - if (ret < 0) - goto out; + dss_exec(&remove_pid, argv[0], argv); snapshot_removal_status = HS_RUNNING; out: free(new_name); @@ -285,7 +425,7 @@ static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl) struct snapshot *s; int i; - DSS_DEBUG_LOG("looking for orphaned snapshots\n"); + DSS_DEBUG_LOG(("looking for orphaned snapshots\n")); FOR_EACH_SNAPSHOT(s, i, sl) { if (snapshot_is_being_created(s)) continue; @@ -330,7 +470,7 @@ static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) struct snapshot *s; unsigned missing = 0; - DSS_DEBUG_LOG("looking for intervals containing too many snapshots\n"); + DSS_DEBUG_LOG(("looking for intervals containing too many snapshots\n")); for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) { unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg); unsigned num = sl->interval_count[interval]; @@ -339,8 +479,6 @@ static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) if (keep >= num) missing += keep - num; -// DSS_DEBUG_LOG("interval %i: keep: %u, have: %u, missing: %u\n", -// interval, keep, num, missing); if (keep + missing >= num) continue; /* redundant snapshot in this interval, pick snapshot with lowest score */ @@ -351,7 +489,6 @@ static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) continue; if (is_reference_snapshot(s)) continue; - //DSS_DEBUG_LOG("checking %s\n", s->name); if (s->interval > interval) { prev = s; continue; @@ -367,7 +504,6 @@ static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) /* check if s is a better victim */ this_score = s->creation_time - prev->creation_time; assert(this_score >= 0); - //DSS_DEBUG_LOG("%s: score %lli\n", s->name, (long long)score); if (this_score < score) { score = this_score; victim = s; @@ -385,50 +521,65 @@ static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl) int i; struct snapshot *s; - DSS_DEBUG_LOG("looking for snapshots belonging to intervals greater than %d\n", - conf.num_intervals_arg); + DSS_DEBUG_LOG(("looking for snapshots belonging to intervals >= %d\n", + conf.num_intervals_arg)); FOR_EACH_SNAPSHOT(s, i, sl) { if (snapshot_is_being_created(s)) continue; if (is_reference_snapshot(s)) continue; - if (s->interval <= conf.num_intervals_arg) + if (s->interval < conf.num_intervals_arg) continue; return s; } return NULL; } -struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl) +static struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl) { - int i; - struct snapshot *s; + int i, num_complete; + struct snapshot *s, *ref = NULL; + + num_complete = num_complete_snapshots(sl); + if (num_complete <= conf.min_complete_arg) + return NULL; FOR_EACH_SNAPSHOT(s, i, sl) { if (snapshot_is_being_created(s)) continue; - if (is_reference_snapshot(s)) + if (is_reference_snapshot(s)) { /* avoid this one */ + ref = s; continue; - DSS_INFO_LOG("oldest removable snapshot: %s\n", s->name); + } + DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name)); return s; } - return NULL; + assert(ref); + DSS_WARNING_LOG(("removing reference snapshot %s\n", ref->name)); + return ref; } static int rename_incomplete_snapshot(int64_t start) { char *old_name; int ret; + int64_t now; + /* + * We don't want the dss_rename() below to fail with EEXIST because the + * last complete snapshot was created (and completed) in the same + * second as this one. + */ + while ((now = get_current_time()) == start) + sleep(1); free(path_to_last_complete_snapshot); - ret = complete_name(start, get_current_time(), - &path_to_last_complete_snapshot); + ret = complete_name(start, now, &path_to_last_complete_snapshot); if (ret < 0) return ret; old_name = incomplete_name(start); ret = dss_rename(old_name, path_to_last_complete_snapshot); if (ret >= 0) - DSS_NOTICE_LOG("%s -> %s\n", old_name, - path_to_last_complete_snapshot); + DSS_NOTICE_LOG(("%s -> %s\n", old_name, + path_to_last_complete_snapshot)); free(old_name); return ret; } @@ -442,18 +593,33 @@ static int try_to_free_disk_space(void) const char *why; int low_disk_space; - ret = disk_space_low(); + ret = disk_space_low(NULL); 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 && conf.keep_redundant_given) - 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; + } + /* + * Idle and --keep_redundant not given, or low disk space. Look at + * existing snapshots. + */ dss_get_snapshot_list(&sl); ret = 0; - if (!low_disk_space && sl.num_snapshots <= 1) + /* + * Don't remove anything if there is free space and we have fewer + * snapshots than configured, plus one. This way there is always one + * snapshot that can be recycled. + */ + if (!low_disk_space && sl.num_snapshots <= 1 << conf.num_intervals_arg) goto out; why = "outdated"; victim = find_outdated_snapshot(&sl); @@ -463,91 +629,94 @@ static int try_to_free_disk_space(void) 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"); + /* try harder only if disk space is low */ + if (!low_disk_space) + goto out; + DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n")); victim = find_oldest_removable_snapshot(&sl); if (victim) goto remove; - DSS_CRIT_LOG("uhuhu: disk space low and nothing to remove\n"); + 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); + pre_remove_hook(victim, why); out: free_snapshot_list(&sl); return ret; } -static int post_create_hook(void) +static void post_create_hook(void) { - int ret, fds[3] = {0, 0, 0}; - char *cmd; - - if (!conf.post_create_hook_given) { - snapshot_creation_status = HS_READY; - return 0; - } - cmd = make_message("%s %s/%s", conf.post_create_hook_arg, + char *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); + DSS_NOTICE_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&create_pid, cmd); free(cmd); - if (ret < 0) - return ret; snapshot_creation_status = HS_POST_RUNNING; - return ret; } -static int post_remove_hook(void) +static void post_remove_hook(void) { - int ret, fds[3] = {0, 0, 0}; char *cmd; struct snapshot *s = snapshot_currently_being_removed; assert(s); - if (!conf.post_remove_hook_given) { - snapshot_removal_status = HS_READY; - return 0; - } 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(&remove_pid, cmd, fds); + DSS_NOTICE_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&remove_pid, cmd); free(cmd); - if (ret < 0) - return ret; snapshot_removal_status = HS_POST_RUNNING; - return ret; } -static void kill_process(pid_t pid) +static void dss_kill(pid_t pid, int sig, const char *msg) { - if (!pid) + const char *signame, *process_name; + + if (pid == 0) + return; + switch (sig) { + case SIGTERM: signame = "TERM"; break; + case SIGSTOP: signame = "STOP"; break; + case SIGCONT: signame = "CONT"; break; + default: signame = "????"; + } + + if (pid == create_pid) + process_name = "create"; + else if (pid == remove_pid) + process_name = "remove"; + else process_name = "??????"; + + if (msg) + DSS_INFO_LOG(("%s\n", msg)); + DSS_DEBUG_LOG(("sending signal %d (%s) to pid %d (%s process)\n", + sig, signame, (int)pid, process_name)); + if (kill(pid, sig) >= 0) return; - DSS_WARNING_LOG("sending SIGTERM to pid %d\n", (int)pid); - kill(pid, SIGTERM); + DSS_INFO_LOG(("failed to send signal %d (%s) to pid %d (%s process)\n", + sig, signame, (int)pid, process_name)); } static void stop_create_process(void) { - if (!create_pid || create_process_stopped) + if (create_process_stopped) return; - kill(SIGSTOP, create_pid); + dss_kill(create_pid, SIGSTOP, "suspending create process"); create_process_stopped = 1; } static void restart_create_process(void) { - if (!create_pid || !create_process_stopped) + if (!create_process_stopped) return; - kill (SIGCONT, create_pid); + dss_kill(create_pid, SIGCONT, "resuming create process"); create_process_stopped = 0; } @@ -557,20 +726,20 @@ static void restart_create_process(void) static void log_termination_msg(pid_t pid, int status) { if (WIFEXITED(status)) - DSS_INFO_LOG("child %i exited. Exit status: %i\n", (int)pid, - WEXITSTATUS(status)); + DSS_INFO_LOG(("child %i exited. Exit status: %i\n", (int)pid, + WEXITSTATUS(status))); else if (WIFSIGNALED(status)) - DSS_NOTICE_LOG("child %i was killed by signal %i\n", (int)pid, - WTERMSIG(status)); + DSS_NOTICE_LOG(("child %i was killed by signal %i\n", (int)pid, + WTERMSIG(status))); else - DSS_WARNING_LOG("child %i terminated abormally\n", (int)pid); + DSS_WARNING_LOG(("child %i terminated abormally\n", (int)pid)); } static int wait_for_process(pid_t pid, int *status) { int ret; - DSS_DEBUG_LOG("Waiting for process %d to terminate\n", (int)pid); + DSS_DEBUG_LOG(("Waiting for process %d to terminate\n", (int)pid)); for (;;) { fd_set rfds; @@ -592,11 +761,10 @@ static int wait_for_process(pid_t pid, int *status) } } /* SIGINT or SIGTERM */ - DSS_WARNING_LOG("sending SIGTERM to pid %d\n", (int)pid); - kill(pid, SIGTERM); + dss_kill(pid, SIGTERM, "killing child process"); } if (ret < 0) - DSS_ERROR_LOG("failed to wait for process %d\n", (int)pid); + DSS_ERROR_LOG(("failed to wait for process %d\n", (int)pid)); else log_termination_msg(pid, *status); return ret; @@ -623,10 +791,7 @@ static int handle_rm_exit(int 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; + snapshot_removal_status = HS_SUCCESS; return 1; } @@ -686,7 +851,7 @@ static int handle_rsync_exit(int status) int es, ret; if (!WIFEXITED(status)) { - DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)create_pid); + DSS_ERROR_LOG(("rsync process %d died involuntary\n", (int)create_pid)); ret = -E_INVOLUNTARY_EXIT; snapshot_creation_status = HS_READY; goto out; @@ -694,24 +859,27 @@ static int handle_rsync_exit(int status) es = WEXITSTATUS(status); /* * Restart rsync on non-fatal errors: - * 12: Error in rsync protocol data stream - * 13: Errors with program diagnostics + * 24: Partial transfer due to vanished source files */ - if (es == 12 || es == 13) { - DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n", - (int)create_pid, es); + if (es != 0 && es != 24) { + DSS_WARNING_LOG(("rsync exit code %d, error count %d\n", + es, ++num_consecutive_rsync_errors)); + if (conf.create_given) { + ret = -E_BAD_EXIT_CODE; + goto out; + } + if (num_consecutive_rsync_errors > conf.max_rsync_errors_arg) { + ret = -E_TOO_MANY_RSYNC_ERRORS; + snapshot_creation_status = HS_READY; + goto out; + } + DSS_WARNING_LOG(("restarting rsync process\n")); snapshot_creation_status = HS_NEEDS_RESTART; - gettimeofday(&next_snapshot_time, NULL); - next_snapshot_time.tv_sec += 60; + 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)create_pid, es); - ret = -E_BAD_EXIT_CODE; - snapshot_creation_status = HS_READY; - goto out; - } + num_consecutive_rsync_errors = 0; ret = rename_incomplete_snapshot(current_snapshot_creation_time); if (ret < 0) goto out; @@ -719,7 +887,6 @@ static int handle_rsync_exit(int status) free(name_of_reference_snapshot); name_of_reference_snapshot = NULL; out: - create_pid = 0; create_process_stopped = 0; return ret; } @@ -737,13 +904,12 @@ static int handle_pre_create_hook_exit(int status) es = WEXITSTATUS(status); if (es) { 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"); + 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 */ } - gettimeofday(&next_snapshot_time, NULL); - next_snapshot_time.tv_sec += 60; + next_snapshot_time = get_current_time() + 60; snapshot_creation_status = HS_READY; ret = 0; goto out; @@ -752,7 +918,6 @@ static int handle_pre_create_hook_exit(int status) snapshot_creation_status = HS_PRE_SUCCESS; ret = 1; out: - create_pid = 0; return ret; } @@ -767,17 +932,22 @@ static int handle_sigchld(void) if (pid == create_pid) { switch (snapshot_creation_status) { case HS_PRE_RUNNING: - return handle_pre_create_hook_exit(status); + ret = handle_pre_create_hook_exit(status); + break; case HS_RUNNING: - return handle_rsync_exit(status); + ret = handle_rsync_exit(status); + break; case HS_POST_RUNNING: snapshot_creation_status = HS_READY; - return 1; + ret = 1; + break; default: - DSS_EMERG_LOG("BUG: create can't die in status %d\n", - snapshot_creation_status); + DSS_EMERG_LOG(("BUG: create can't die in status %d\n", + snapshot_creation_status)); return -E_BUG; } + create_pid = 0; + return ret; } if (pid == remove_pid) { ret = handle_remove_exit(status); @@ -785,61 +955,58 @@ static int handle_sigchld(void) return ret; return ret; } - DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid); + DSS_EMERG_LOG(("BUG: unknown process %d died\n", (int)pid)); return -E_BUG; } static int check_config(void) { if (conf.unit_interval_arg <= 0) { - DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg); + DSS_ERROR_LOG(("bad unit interval: %i\n", conf.unit_interval_arg)); return -E_INVALID_NUMBER; } - DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg); - if (conf.num_intervals_arg <= 0) { - DSS_ERROR_LOG("bad number of intervals %i\n", conf.num_intervals_arg); + DSS_DEBUG_LOG(("unit interval: %i day(s)\n", conf.unit_interval_arg)); + if (conf.num_intervals_arg <= 0 || conf.num_intervals_arg > 30) { + DSS_ERROR_LOG(("bad number of intervals: %i\n", + conf.num_intervals_arg)); return -E_INVALID_NUMBER; } - DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg); + DSS_DEBUG_LOG(("number of intervals: %i\n", conf.num_intervals_arg)); return 1; } -static int 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(bool sighup) { - int ret; - char *config_file; + int ret, config_file_exists; + char *config_file = get_config_file_name(); struct stat statbuf; char *old_logfile_arg = NULL; int old_daemon_given = 0; - if (conf.config_file_given) - config_file = dss_strdup(conf.config_file_arg); - else { - char *home = get_homedir(); - config_file = make_message("%s/.dssrc", home); - free(home); - } - if (override) { /* SIGHUP */ + if (sighup) { if (conf.logfile_given) old_logfile_arg = dss_strdup(conf.logfile_arg); 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); + DSS_ERROR_LOG(("failed to stat config file %s\n", config_file)); goto out; } - if (!ret) { - struct cmdline_parser_params params = { - .override = override, - .initialize = 0, - .check_required = 1, - .check_ambiguity = 0, - .print_errors = 1 - }; - if (override) { /* invalidate all rsync options */ + if (config_file_exists) { + struct cmdline_parser_params params; + params.override = sighup; + params.initialize = 0; + params.check_required = 1; + params.check_ambiguity = 0; + params.print_errors = 1; + if (sighup) { /* invalidate all rsync options */ int i; for (i = 0; i < conf.rsync_option_given; i++) { @@ -853,7 +1020,7 @@ static int parse_config_file(int override) ret = check_config(); if (ret < 0) goto out; - if (override) { + if (sighup) { /* don't change daemon mode on SIGHUP */ conf.daemon_given = old_daemon_given; close_log(logfile); @@ -865,22 +1032,22 @@ static int parse_config_file(int override) conf.logfile_given = 1; } } - if (conf.logfile_given) { + if (conf.logfile_given && conf.run_given && conf.daemon_given) { logfile = open_log(conf.logfile_arg); log_welcome(conf.loglevel_arg); } - DSS_DEBUG_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) - DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); + DSS_EMERG_LOG(("%s\n", dss_strerror(-ret))); return ret; } static int change_to_dest_dir(void) { - DSS_INFO_LOG("changing cwd to %s\n", conf.dest_dir_arg); + DSS_INFO_LOG(("changing cwd to %s\n", conf.dest_dir_arg)); return dss_chdir(conf.dest_dir_arg); } @@ -888,13 +1055,23 @@ static int handle_sighup(void) { int ret; - DSS_NOTICE_LOG("SIGHUP\n"); - ret = parse_config_file(1); + DSS_NOTICE_LOG(("SIGHUP, re-reading config\n")); + dump_dss_config("old"); + ret = parse_config_file(true /* SIGHUP */); if (ret < 0) return ret; + dump_dss_config("reloaded"); + invalidate_next_snapshot_time(); return change_to_dest_dir(); } +static void kill_children(void) +{ + restart_create_process(); + dss_kill(create_pid, SIGTERM, NULL); + dss_kill(remove_pid, SIGTERM, NULL); +} + static int handle_signal(void) { int sig, ret = next_signal(); @@ -905,9 +1082,7 @@ static int handle_signal(void) switch (sig) { case SIGINT: case SIGTERM: - restart_create_process(); - kill_process(create_pid); - kill_process(remove_pid); + kill_children(); ret = -E_SIGNAL; break; case SIGHUP: @@ -919,7 +1094,7 @@ static int handle_signal(void) } out: if (ret < 0) - DSS_ERROR_LOG("%s\n", dss_strerror(-ret)); + DSS_ERROR_LOG(("%s\n", dss_strerror(-ret))); return ret; } @@ -938,6 +1113,60 @@ static int use_rsync_locally(char *logname) return 1; } +static int rename_resume_snap(int64_t creation_time) +{ + struct snapshot_list sl; + struct snapshot *s = NULL; + char *new_name = incomplete_name(creation_time); + int ret; + const char *why; + + sl.num_snapshots = 0; + + ret = 0; + if (conf.no_resume_given) + goto out; + dss_get_snapshot_list(&sl); + /* + * Snapshot recycling: We first look at the newest snapshot. If this + * snapshot happens to be incomplete, the last rsync process was + * aborted and we reuse this one. Otherwise we look at snapshots which + * could be removed (outdated and redundant snapshots) as candidates + * for recycling. If no outdated/redundant snapshot exists, we check if + * there is an orphaned snapshot, which likely is useless anyway. + * + * Only if no existing snapshot is suitable for recycling, we bite the + * bullet and create a new one. + */ + s = get_newest_snapshot(&sl); + if (!s) /* no snapshots at all */ + goto out; + /* re-use last snapshot if it is incomplete */ + why = "aborted"; + if ((s->flags & SS_COMPLETE) == 0) + goto out; + why = "outdated"; + s = find_outdated_snapshot(&sl); + if (s) + goto out; + why = "redundant"; + s = find_redundant_snapshot(&sl); + if (s) + goto out; + why = "orphaned"; + s = find_orphaned_snapshot(&sl); +out: + if (s) { + DSS_INFO_LOG(("reusing %s snapshot %s\n", why, s->name)); + ret = dss_rename(s->name, new_name); + } + if (ret >= 0) + DSS_NOTICE_LOG(("creating new snapshot %s\n", new_name)); + free(new_name); + free_snapshot_list(&sl); + return ret; +} + static void create_rsync_argv(char ***argv, int64_t *num) { char *logname; @@ -951,16 +1180,16 @@ static void create_rsync_argv(char ***argv, int64_t *num) *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *)); (*argv)[i++] = dss_strdup("rsync"); - (*argv)[i++] = dss_strdup("-aq"); + (*argv)[i++] = dss_strdup("-a"); (*argv)[i++] = dss_strdup("--delete"); for (j = 0; j < conf.rsync_option_given; j++) (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]); if (name_of_reference_snapshot) { - DSS_INFO_LOG("using %s as reference\n", 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 suitable reference snapshot found\n"); + DSS_INFO_LOG(("no suitable reference snapshot found\n")); logname = dss_logname(); if (use_rsync_locally(logname)) (*argv)[i++] = dss_strdup(conf.source_dir_arg); @@ -973,7 +1202,7 @@ static void create_rsync_argv(char ***argv, int64_t *num) (*argv)[i++] = incomplete_name(*num); (*argv)[i++] = NULL; for (j = 0; j < i; j++) - DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]); + DSS_DEBUG_LOG(("argv[%d] = %s\n", j, (*argv)[j])); } static void free_rsync_argv(char **argv) @@ -989,15 +1218,12 @@ static void free_rsync_argv(char **argv) static int create_snapshot(char **argv) { - int ret, fds[3] = {0, 0, 0}; - char *name; + int ret; - name = incomplete_name(current_snapshot_creation_time); - DSS_NOTICE_LOG("creating new snapshot %s\n", name); - free(name); - ret = dss_exec(&create_pid, argv[0], argv, fds); + ret = rename_resume_snap(current_snapshot_creation_time); if (ret < 0) return ret; + dss_exec(&create_pid, argv[0], argv); snapshot_creation_status = HS_RUNNING; return ret; } @@ -1022,7 +1248,6 @@ static int select_loop(void) } FD_ZERO(&rfds); FD_SET(signal_pipe, &rfds); - 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) goto out; @@ -1040,9 +1265,7 @@ static int select_loop(void) continue; } if (snapshot_removal_status == HS_SUCCESS) { - ret = post_remove_hook(); - if (ret < 0) - goto out; + post_remove_hook(); continue; } ret = try_to_free_disk_space(); @@ -1057,28 +1280,31 @@ static int select_loop(void) case HS_READY: if (!next_snapshot_is_due()) continue; - ret = pre_create_hook(); - if (ret < 0) - goto out; + pre_create_hook(); continue; case HS_PRE_RUNNING: case HS_RUNNING: case HS_POST_RUNNING: continue; case HS_PRE_SUCCESS: - free_rsync_argv(rsync_argv); - create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); - /* fall through */ - case HS_NEEDS_RESTART: + if (!name_of_reference_snapshot) { + free_rsync_argv(rsync_argv); + create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); + } ret = create_snapshot(rsync_argv); if (ret < 0) goto out; continue; - case HS_SUCCESS: - ret = post_create_hook(); + case HS_NEEDS_RESTART: + if (!next_snapshot_is_due()) + continue; + ret = create_snapshot(rsync_argv); if (ret < 0) goto out; continue; + case HS_SUCCESS: + post_create_hook(); + continue; } } out: @@ -1087,22 +1313,36 @@ out: static void exit_hook(int exit_code) { - int fds[3] = {0, 0, 0}; - char *argv[] = {conf.exit_hook_arg, dss_strerror(-exit_code), NULL}; + char *argv[3]; 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); + argv[0] = conf.exit_hook_arg; + argv[1] = dss_strerror(-exit_code); + argv[2] = NULL; + + DSS_NOTICE_LOG(("executing %s %s\n", argv[0], argv[1])); + dss_exec(&pid, conf.exit_hook_arg, argv); +} + +static void lock_dss_or_die(void) +{ + char *config_file = get_config_file_name(); + int ret = lock_dss(config_file); + + free(config_file); + if (ret < 0) { + DSS_EMERG_LOG(("failed to lock: %s\n", dss_strerror(-ret))); + exit(EXIT_FAILURE); + } } static int com_run(void) { int ret; + lock_dss_or_die(); if (conf.dry_run_given) { - DSS_ERROR_LOG("dry_run not supported by this command\n"); + DSS_ERROR_LOG(("dry_run not supported by this command\n")); return -E_SYNTAX; } ret = install_sighandler(SIGHUP); @@ -1111,6 +1351,7 @@ static int com_run(void) ret = select_loop(); if (ret >= 0) /* impossible */ ret = -E_BUG; + kill_children(); exit_hook(ret); return ret; } @@ -1123,6 +1364,7 @@ static int com_prune(void) struct disk_space ds; const char *why; + lock_dss_or_die(); ret = get_disk_space(".", &ds); if (ret < 0) return ret; @@ -1145,9 +1387,7 @@ rm: ret = 0; goto out; } - ret = pre_remove_hook(victim, why); - if (ret < 0) - goto out; + pre_remove_hook(victim, why); if (snapshot_removal_status == HS_PRE_RUNNING) { ret = wait_for_remove_process(); if (ret < 0) @@ -1163,9 +1403,7 @@ rm: goto out; if (snapshot_removal_status != HS_SUCCESS) goto out; - ret = post_remove_hook(); - if (ret < 0) - goto out; + post_remove_hook(); if (snapshot_removal_status != HS_POST_RUNNING) goto out; ret = wait_for_remove_process(); @@ -1182,6 +1420,7 @@ static int com_create(void) int ret, status; char **rsync_argv; + lock_dss_or_die(); if (conf.dry_run_given) { int i; char *msg = NULL; @@ -1197,9 +1436,7 @@ static int com_create(void) free(msg); return 1; } - ret = pre_create_hook(); - if (ret < 0) - return ret; + pre_create_hook(); if (create_pid) { ret = wait_for_process(create_pid, &status); if (ret < 0) @@ -1238,7 +1475,7 @@ static int com_ls(void) 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; } @@ -1247,7 +1484,7 @@ static int setup_signal_handling(void) { int ret; - DSS_INFO_LOG("setting up signal handlers\n"); + DSS_INFO_LOG(("setting up signal handlers\n")); signal_pipe = signal_init(); /* always successful */ ret = install_sighandler(SIGINT); if (ret < 0) @@ -1258,38 +1495,48 @@ static int setup_signal_handling(void) return install_sighandler(SIGCHLD); } -/** - * The main function of dss. - * - * \param argc Usual argument count. - * \param argv Usual argument vector. - */ int main(int argc, char **argv) { int ret; - struct cmdline_parser_params params = { - .override = 0, - .initialize = 1, - .check_required = 0, - .check_ambiguity = 0, - .print_errors = 1 - }; + struct cmdline_parser_params params; + + params.override = 0; + params.initialize = 1; + params.check_required = 0; + params.check_ambiguity = 0; + params.print_errors = 1; cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */ ret = parse_config_file(0); + ret = parse_config_file(false /* no SIGHUP */); 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. + */ + struct cmdline_parser_params params; + params.override = 1; + params.initialize = 1; + params.check_required = 1; + params.check_ambiguity = 1; + params.print_errors = 1; + cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */ + } if (conf.daemon_given) daemon_init(); ret = change_to_dest_dir(); if (ret < 0) goto out; + dump_dss_config("startup"); ret = setup_signal_handling(); if (ret < 0) goto out; ret = call_command_handler(); + signal_shutdown(); out: if (ret < 0) - DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); + DSS_EMERG_LOG(("%s\n", dss_strerror(-ret))); exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE); }