X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=6dbe11f6ba7e5fd3541a0364228b6fc81562b793;hp=ad62c3c04bdb1f937b41d07a860a0007589e3fe4;hb=0ca40f54698dc00d81e40f784e27628f8fe802c0;hpb=37da57359abfe349f22bd82b39719fe07a19e895 diff --git a/dss.c b/dss.c index ad62c3c..6dbe11f 100644 --- a/dss.c +++ b/dss.c @@ -40,24 +40,22 @@ 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; /** Creation time of the snapshot currently being created. */ static int64_t current_snapshot_creation_time; /** Needed by the post-create hook. */ static char *path_to_last_complete_snapshot; /** \sa \ref snap.h for details. */ static unsigned snapshot_creation_status; +/** \sa \ref snap.h for details. */ +static unsigned snapshot_removal_status; DEFINE_DSS_ERRLIST; @@ -195,7 +193,7 @@ out: static int remove_snapshot(struct snapshot *s, char *why) { int fds[3] = {0, 0, 0}; - assert(!rm_pid); + assert(!remove_pid); char *new_name = being_deleted_name(s); int ret = dss_rename(s->name, new_name); char *argv[] = {"rm", "-rf", new_name, NULL}; @@ -204,7 +202,7 @@ static int remove_snapshot(struct snapshot *s, char *why) goto out; DSS_NOTICE_LOG("removing %s snapshot %s (interval = %i)\n", why, s->name, s->interval); - ret = dss_exec(&rm_pid, argv[0], argv, fds); + ret = dss_exec(&remove_pid, argv[0], argv, fds); out: free(new_name); return ret; @@ -371,8 +369,8 @@ static int pre_create_hook(void) snapshot_creation_status = SCS_PRE_HOOK_SUCCESS; return 0; } - DSS_NOTICE_LOG("executing %s\n", conf.pre_create_hook_arg); - ret = dss_exec_cmdline_pid(&pre_create_hook_pid, + 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; @@ -393,7 +391,7 @@ static int post_create_hook(void) 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(&post_create_hook_pid, cmd, fds); + ret = dss_exec_cmdline_pid(&create_pid, cmd, fds); free(cmd); if (ret < 0) return ret; @@ -409,23 +407,22 @@ 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. */ @@ -479,7 +476,7 @@ static int wait_for_process(pid_t pid, int *status) static int handle_rm_exit(int status) { - rm_pid = 0; + remove_pid = 0; if (!WIFEXITED(status)) return -E_INVOLUNTARY_EXIT; if (WEXITSTATUS(status)) @@ -489,7 +486,7 @@ static int handle_rm_exit(int status) static int wait_for_rm_process(void) { - int status, ret = wait_for_process(rm_pid, &status); + int status, ret = wait_for_process(remove_pid, &status); if (ret < 0) return ret; @@ -501,7 +498,7 @@ 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(); @@ -510,7 +507,7 @@ static int handle_rsync_exit(int status) es = WEXITSTATUS(status); if (es == 13) { /* Errors with program diagnostics */ DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n", - (int)rsync_pid, es); + (int)create_pid, es); snapshot_creation_status = SCS_RSYNC_NEEDS_RESTART; gettimeofday(&next_snapshot_time, NULL); next_snapshot_time.tv_sec += 60; @@ -518,7 +515,7 @@ static int handle_rsync_exit(int status) 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(); @@ -529,14 +526,15 @@ static int handle_rsync_exit(int status) goto out; snapshot_creation_status = SCS_RSYNC_SUCCESS; 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; @@ -546,15 +544,22 @@ 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"); + warn_count = 60; /* warn only once per hour */ + } snapshot_creation_status = SCS_READY; compute_next_snapshot_time(); - ret = -E_BAD_EXIT_CODE; + ret = 0; goto out; } + warn_count = 0; snapshot_creation_status = SCS_PRE_HOOK_SUCCESS; ret = 1; out: - pre_create_hook_pid = 0; + create_pid = 0; return ret; } @@ -565,17 +570,25 @@ 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 SCS_PRE_HOOK_RUNNING: + return handle_pre_create_hook_exit(status); + case SCS_RSYNC_RUNNING: + return handle_rsync_exit(status); + case SCS_POST_HOOK_RUNNING: + snapshot_creation_status = SCS_READY; + compute_next_snapshot_time(); + 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) + return handle_rm_exit(status); DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid); return -E_BUG; } @@ -696,9 +709,9 @@ static int handle_signal(void) switch (sig) { case SIGINT: case SIGTERM: - restart_rsync_process(); - kill_process(rsync_pid); - kill_process(rm_pid); + restart_create_process(); + kill_process(create_pid); + kill_process(remove_pid); ret = -E_SIGNAL; break; case SIGHUP: @@ -785,7 +798,7 @@ 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; @@ -804,7 +817,7 @@ static int select_loop(void) int low_disk_space; struct timeval now, *tvp; - if (rm_pid) + if (remove_pid) tvp = NULL; /* sleep until rm process dies */ else { /* sleep one minute */ tv.tv_sec = 60; @@ -822,7 +835,7 @@ static int select_loop(void) if (ret < 0) goto out; } - if (rm_pid) + if (remove_pid) continue; ret = disk_space_low(); if (ret < 0) @@ -831,11 +844,11 @@ static int select_loop(void) ret = try_to_free_disk_space(low_disk_space); if (ret < 0) goto out; - if (rm_pid) { - stop_rsync_process(); + if (remove_pid) { + stop_create_process(); continue; } - restart_rsync_process(); + restart_create_process(); gettimeofday(&now, NULL); if (tv_diff(&next_snapshot_time, &now, NULL) > 0) continue; @@ -967,27 +980,27 @@ 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;