X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=531beb60508045a3f40e983b80edc7102a3f4c26;hp=f04be8f95595a41b33478a1823ea77f53389ca35;hb=f92d4b984e14d18f468151ac8596dc0159ff838e;hpb=676f0d8d399ade79ff579e28787a63f00bdf2ce3 diff --git a/dss.c b/dss.c index f04be8f..531beb6 100644 --- a/dss.c +++ b/dss.c @@ -47,7 +47,7 @@ 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; +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. */ @@ -151,22 +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 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; + 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)) @@ -175,41 +169,51 @@ static int next_snapshot_is_due(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 */ - 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_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; + 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 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(); + + 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); - if (!conf.pre_create_hook_given) { - snapshot_creation_status = HS_PRE_SUCCESS; - return 0; - } + /* 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); ret = dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg, fds); @@ -235,15 +239,10 @@ 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); + ret = dss_exec_cmdline_pid(&remove_pid, cmd, fds); free(cmd); if (ret < 0) return ret; @@ -495,10 +494,6 @@ static int 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, conf.dest_dir_arg, path_to_last_complete_snapshot); DSS_NOTICE_LOG("executing %s\n", cmd); @@ -518,10 +513,6 @@ static int post_remove_hook(void) 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); @@ -533,27 +524,48 @@ static int post_remove_hook(void) 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; - DSS_WARNING_LOG("sending SIGTERM to pid %d\n", (int)pid); - kill(pid, SIGTERM); + 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_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; } @@ -598,8 +610,7 @@ 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); @@ -629,10 +640,7 @@ 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; } @@ -707,8 +715,7 @@ static int handle_rsync_exit(int status) DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n", (int)create_pid, es); 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; } @@ -725,7 +732,6 @@ 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; } @@ -748,8 +754,7 @@ static int handle_pre_create_hook_exit(int status) 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; @@ -758,7 +763,6 @@ static int handle_pre_create_hook_exit(int status) snapshot_creation_status = HS_PRE_SUCCESS; ret = 1; out: - create_pid = 0; return ret; } @@ -773,17 +777,22 @@ 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); return -E_BUG; } + create_pid = 0; + return ret; } if (pid == remove_pid) { ret = handle_remove_exit(status); @@ -810,9 +819,13 @@ static int check_config(void) return 1; } +/* + * 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; @@ -831,13 +844,13 @@ static int 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, @@ -876,7 +889,7 @@ static int parse_config_file(int override) log_welcome(conf.loglevel_arg); } DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg); -// cmdline_parser_dump(logfile? logfile : stdout, &conf); + ret = config_file_exists; out: free(config_file); if (ret < 0) @@ -890,14 +903,25 @@ static int change_to_dest_dir(void) return dss_chdir(conf.dest_dir_arg); } +static void dump_dss_config(const char *msg) +{ + if (conf.loglevel_arg > INFO) + return; + DSS_INFO_LOG("%s\n", msg); + cmdline_parser_dump(logfile? logfile : stderr, &conf); +} + static int handle_sighup(void) { int ret; - DSS_NOTICE_LOG("SIGHUP\n"); + 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(); } @@ -912,8 +936,8 @@ static int handle_signal(void) case SIGINT: case SIGTERM: restart_create_process(); - kill_process(create_pid); - kill_process(remove_pid); + dss_kill(create_pid, SIGTERM, NULL); + dss_kill(remove_pid, SIGTERM, NULL); ret = -E_SIGNAL; break; case SIGHUP: @@ -944,6 +968,32 @@ static int use_rsync_locally(char *logname) return 1; } +static int rename_resume_snap(int64_t creation_time) +{ + struct snapshot_list sl = {.num_snapshots = 0}; + struct snapshot *s; + char *new_name = incomplete_name(creation_time); + int ret; + + ret = 0; + if (conf.no_resume_given) + goto out; + dss_get_snapshot_list(&sl); + s = get_newest_snapshot(&sl); + if (!s) + goto out; + if ((s->flags & SS_COMPLETE) != 0) /* complete */ + goto out; + DSS_INFO_LOG("resuming: reusing %s as destination dir\n", s->name); + ret = dss_rename(s->name, new_name); +out: + 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; @@ -996,11 +1046,10 @@ static void free_rsync_argv(char **argv) static int create_snapshot(char **argv) { int ret, fds[3] = {0, 0, 0}; - char *name; - name = incomplete_name(current_snapshot_creation_time); - DSS_NOTICE_LOG("creating new snapshot %s\n", name); - free(name); + ret = rename_resume_snap(current_snapshot_creation_time); + if (ret < 0) + return ret; ret = dss_exec(&create_pid, argv[0], argv, fds); if (ret < 0) return ret; @@ -1028,7 +1077,6 @@ 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; @@ -1072,10 +1120,17 @@ static int select_loop(void) 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 */ + 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_NEEDS_RESTART: + if (!next_snapshot_is_due()) + continue; ret = create_snapshot(rsync_argv); if (ret < 0) goto out; @@ -1097,8 +1152,6 @@ static void exit_hook(int exit_code) 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); } @@ -1285,8 +1338,23 @@ int main(int argc, char **argv) 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(); + dump_dss_config("dss configuration"); ret = change_to_dest_dir(); if (ret < 0) goto out;