X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=12ad11cfdfc22e9707cb340a291785bfbfc2bf87;hp=ad62c3c04bdb1f937b41d07a860a0007589e3fe4;hb=df4a2d392aa10cc73e66fedc24a4e3703ec5335e;hpb=a1ae667ebd08544d8d87f1eebe289d26cbe98752 diff --git a/dss.c b/dss.c index ad62c3c..12ad11c 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; +enum hook_status snapshot_creation_status; +/** \sa \ref snap.h for details. */ +enum hook_status snapshot_removal_status; DEFINE_DSS_ERRLIST; @@ -159,7 +157,7 @@ static void compute_next_snapshot_time(void) struct snapshot *s = NULL; struct snapshot_list sl; - assert(snapshot_creation_status == SCS_READY); + assert(snapshot_creation_status == HS_READY); current_snapshot_creation_time = 0; dss_get_snapshot_list(&sl); FOR_EACH_SNAPSHOT(s, i, &sl) { @@ -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; @@ -368,15 +366,15 @@ static int pre_create_hook(void) int ret, fds[3] = {0, 0, 0}; if (!conf.pre_create_hook_given) { - snapshot_creation_status = SCS_PRE_HOOK_SUCCESS; + snapshot_creation_status = HS_PRE_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; - snapshot_creation_status = SCS_PRE_HOOK_RUNNING; + snapshot_creation_status = HS_PRE_RUNNING; return ret; } @@ -386,18 +384,18 @@ static int post_create_hook(void) char *cmd; if (!conf.post_create_hook_given) { - snapshot_creation_status = SCS_READY; + snapshot_creation_status = HS_READY; compute_next_snapshot_time(); 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); - 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; - snapshot_creation_status = SCS_POST_HOOK_RUNNING; + snapshot_creation_status = HS_POST_RUNNING; 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; @@ -501,60 +498,68 @@ 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; + snapshot_creation_status = HS_READY; compute_next_snapshot_time(); goto out; } es = WEXITSTATUS(status); if (es == 13) { /* Errors with program diagnostics */ DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n", - (int)rsync_pid, es); - snapshot_creation_status = SCS_RSYNC_NEEDS_RESTART; + (int)create_pid, es); + snapshot_creation_status = HS_NEEDS_RESTART; gettimeofday(&next_snapshot_time, NULL); next_snapshot_time.tv_sec += 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; + snapshot_creation_status = HS_READY; compute_next_snapshot_time(); 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; 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; + snapshot_creation_status = HS_READY; compute_next_snapshot_time(); ret = -E_INVOLUNTARY_EXIT; goto out; } es = WEXITSTATUS(status); if (es) { - snapshot_creation_status = SCS_READY; + 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 = HS_READY; compute_next_snapshot_time(); - ret = -E_BAD_EXIT_CODE; + 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; } @@ -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 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; + 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: @@ -785,10 +798,10 @@ 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; } @@ -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) @@ -831,42 +844,42 @@ 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; switch (snapshot_creation_status) { - case SCS_READY: + case HS_READY: ret = pre_create_hook(); if (ret < 0) goto out; continue; - case SCS_PRE_HOOK_RUNNING: + case HS_PRE_RUNNING: continue; - case SCS_RSYNC_NEEDS_RESTART: + case HS_NEEDS_RESTART: ret = create_snapshot(rsync_argv); if (ret < 0) goto out; continue; - case SCS_PRE_HOOK_SUCCESS: + case HS_PRE_SUCCESS: 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 SCS_RSYNC_RUNNING: + case HS_RUNNING: continue; - case SCS_RSYNC_SUCCESS: + case HS_SUCCESS: ret = post_create_hook(); if (ret < 0) goto out; continue; - case SCS_POST_HOOK_RUNNING: + case HS_POST_RUNNING: 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;