X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=745729fae629aa279a1747f5779faa92fe901866;hp=b4ad2d28960a3c89e9b489d365f45ffed1376e8e;hb=42451d3bbe741ebae3c8ad49aa104ae53efdbcdb;hpb=69add8d2b5d6c8f402e9f94d47df732479535f2d diff --git a/dss.c b/dss.c index b4ad2d2..745729f 100644 --- a/dss.c +++ b/dss.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2008-2010 Andre Noll + * Copyright (C) 2008-2011 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -33,6 +33,7 @@ #include "df.h" #include "time.h" #include "snap.h" +#include "ipc.h" /** Command line and config file options. */ static struct gengetopt_args_info conf; @@ -64,7 +65,7 @@ enum hook_status snapshot_removal_status; DEFINE_DSS_ERRLIST; -static const char const *hook_status_description[] = {HOOK_STATUS_ARRAY}; +static const char *hook_status_description[] = {HOOK_STATUS_ARRAY}; /* may be called with ds == NULL. */ static int disk_space_low(struct disk_space *ds) @@ -170,7 +171,10 @@ static void dump_dss_config(const char *msg) 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 @@ -226,6 +230,47 @@ static __printf_1_2 void dss_msg(const char* fmt,...) va_end(argp); } +static char *get_config_file_name(void) +{ + 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.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) { get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg); @@ -287,29 +332,22 @@ static int next_snapshot_is_due(void) return 0; } -static int pre_create_hook(void) +static void 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(); 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_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; + return; DSS_DEBUG_LOG("%s snapshot %s\n", why, s->name); assert(snapshot_removal_status == HS_READY); assert(remove_pid == 0); @@ -322,22 +360,23 @@ static int pre_remove_hook(struct snapshot *s, const char *why) 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, cmd, fds); + 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); @@ -345,9 +384,7 @@ static int exec_rm(void) 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); @@ -418,8 +455,6 @@ 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 */ @@ -430,7 +465,6 @@ 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; @@ -446,7 +480,6 @@ 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; @@ -563,31 +596,24 @@ static int try_to_free_disk_space(void) 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; - - 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_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; @@ -596,12 +622,9 @@ static int post_remove_hook(void) 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_exec_cmdline_pid(&remove_pid, cmd); free(cmd); - if (ret < 0) - return ret; snapshot_removal_status = HS_POST_RUNNING; - return ret; } static void dss_kill(pid_t pid, int sig, const char *msg) @@ -906,18 +929,11 @@ static int check_config(void) static int parse_config_file(int override) { int ret, config_file_exists; - char *config_file; + 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 (conf.logfile_given) old_logfile_arg = dss_strdup(conf.logfile_arg); @@ -931,13 +947,12 @@ static int parse_config_file(int override) goto out; } if (config_file_exists) { - struct cmdline_parser_params params = { - .override = override, - .initialize = 0, - .check_required = 1, - .check_ambiguity = 0, - .print_errors = 1 - }; + struct cmdline_parser_params params; + params.override = override; + params.initialize = 0; + params.check_required = 1; + params.check_ambiguity = 0; + params.print_errors = 1; if (override) { /* invalidate all rsync options */ int i; @@ -1042,23 +1057,51 @@ static int use_rsync_locally(char *logname) static int rename_resume_snap(int64_t creation_time) { - struct snapshot_list sl = {.num_snapshots = 0}; - struct snapshot *s; + 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) + if (!s) /* no snapshots at all */ goto out; - if ((s->flags & SS_COMPLETE) != 0) /* complete */ + /* re-use last snapshot if it is incomplete */ + why = "aborted"; + if ((s->flags & SS_COMPLETE) == 0) goto out; - DSS_INFO_LOG("resuming: reusing %s as destination dir\n", s->name); - ret = dss_rename(s->name, new_name); + 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); @@ -1117,14 +1160,12 @@ static void free_rsync_argv(char **argv) static int create_snapshot(char **argv) { - int ret, fds[3] = {0, 0, 0}; + int ret; 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; + dss_exec(&create_pid, argv[0], argv); snapshot_creation_status = HS_RUNNING; return ret; } @@ -1166,9 +1207,7 @@ 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(); @@ -1183,9 +1222,7 @@ 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: @@ -1208,9 +1245,7 @@ static int select_loop(void) goto out; continue; case HS_SUCCESS: - ret = post_create_hook(); - if (ret < 0) - goto out; + post_create_hook(); continue; } } @@ -1220,18 +1255,34 @@ 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; + 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, fds); + 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"); return -E_SYNTAX; @@ -1254,6 +1305,7 @@ 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; @@ -1276,9 +1328,7 @@ 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) @@ -1294,9 +1344,7 @@ 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(); @@ -1313,6 +1361,7 @@ 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; @@ -1328,9 +1377,7 @@ 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) @@ -1398,13 +1445,13 @@ static int setup_signal_handling(void) 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); @@ -1415,13 +1462,12 @@ int main(int argc, char **argv) * 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 - }; + 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)