X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.c;h=c2aef361287fef0d9a2aafcf787a96ae24f9d37f;hp=af02f1ce0bfcbf20b6858a3b22f762762140e4bf;hb=56f81b0dfa62bb5bf2c338733d9370a8b11bfc39;hpb=38241adb35761475ac010eca4ac1141f3fee79a8 diff --git a/dss.c b/dss.c index af02f1c..c2aef36 100644 --- a/dss.c +++ b/dss.c @@ -1,16 +1,14 @@ -/* - * Copyright (C) 2008 Andre Noll - * - * Licensed under the GPL v2. For licencing details see COPYING. - */ +/* SPDX-License-Identifier: GPL-2.0 */ #include #include +#include #include #include #include #include #include #include +#include #include #include #include @@ -19,68 +17,208 @@ #include #include #include - +#include +#include +#include #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" +#include "dss.lsg.h" + +#define CMD_PTR(_cname) lls_cmd(LSG_DSS_CMD_ ## _cname, dss_suite) +#define OPT_RESULT(_cname, _oname) (lls_opt_result(\ + LSG_DSS_ ## _cname ## _OPT_ ## _oname, (CMD_PTR(_cname) == CMD_PTR(DSS))? lpr : sublpr)) +#define OPT_GIVEN(_cname, _oname) (lls_opt_given(OPT_RESULT(_cname, _oname))) +#define OPT_STRING_VAL(_cname, _oname) (lls_string_val(0, \ + OPT_RESULT(_cname, _oname))) +#define OPT_UINT32_VAL(_cname, _oname) (lls_uint32_val(0, \ + OPT_RESULT(_cname, _oname))) + +struct dss_user_data {int (*handler)(void);}; +#define EXPORT_CMD_HANDLER(_cmd) const struct dss_user_data \ + lsg_dss_com_ ## _cmd ## _user_data = { \ + .handler = com_ ## _cmd \ + }; -/** Command line and config file options. */ -static struct gengetopt_args_info conf; +/* + * Command line and active options. We need to keep a copy of the parsed + * command line options for the SIGHUP case where we merge the command line + * options and the new config file options. + */ +static struct lls_parse_result *cmdline_lpr, *lpr; + +/** Parsed subcommand options. */ +static struct lls_parse_result *cmdline_sublpr, *sublpr; +/* The executing subcommand (NULL at startup). */ +static const struct lls_command *subcmd; +/** Wether daemon_init() was called. */ +static bool daemonized; /** Non-NULL if we log to a file. */ 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; +/** 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; -/** 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; +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. */ static int64_t current_snapshot_creation_time; +/* Set by the pre-rm hook, cleared by handle_remove_exit(). */ +struct snapshot *snapshot_currently_being_removed; /** Needed by the post-create hook. */ static char *path_to_last_complete_snapshot; +static char *name_of_reference_snapshot; +/** \sa \ref snap.h for details. */ +enum hook_status snapshot_creation_status; /** \sa \ref snap.h for details. */ -static unsigned snapshot_creation_status; +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; + uint32_t val; + if (!ds) { + int ret = get_disk_space(".", &ds_struct); + if (ret < 0) + return ret; + ds = &ds_struct; + } + val = OPT_UINT32_VAL(DSS, MIN_FREE_MB); + if (val != 0) + if (ds->free_mb < val) + return 1; + val = OPT_UINT32_VAL(DSS, MIN_FREE_PERCENT); + if (val != 0) + if (ds->percent_free < val) + return 1; + val = OPT_UINT32_VAL(DSS, MIN_FREE_PERCENT_INODES); + if (val != 0) + if (ds->percent_free_inodes < val) + return 1; + return 0; +} -/* a litte cpp magic helps to DRY */ -#define COMMANDS \ - COMMAND(ls) \ - COMMAND(create) \ - COMMAND(prune) \ - COMMAND(run) -#define COMMAND(x) static int com_ ##x(void); -COMMANDS -#undef COMMAND -#define COMMAND(x) if (conf.x ##_given) return com_ ##x(); -static int call_command_handler(void) +static void dump_dss_config(const char *msg) { - COMMANDS - DSS_EMERG_LOG("BUG: did not find command handler\n"); - return -E_BUG; + const char dash[] = "-----------------------------"; + char *lopsub_dump; + int ret; + FILE *log = logfile? logfile : stderr; + struct disk_space ds; + int64_t now = get_current_time(); + + if (OPT_UINT32_VAL(DSS, LOGLEVEL) > 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*** non-default options ***\n\n"); + lopsub_dump = lls_dump_parse_result(lpr, CMD_PTR(DSS), true); + fprintf(log, "%s", lopsub_dump); + free(lopsub_dump); + fprintf(log, "\n*** non-default options for \"run\" ***\n\n"); + lopsub_dump = lls_dump_parse_result(lpr, CMD_PTR(RUN), true); + fprintf(log, "%s", lopsub_dump); + free(lopsub_dump); + fprintf(log, "\n*** internal state ***\n\n"); + fprintf(log, + "pid: %d\n" + "logfile: %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? OPT_STRING_VAL(RUN, LOGFILE) : "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); +} + +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; } -#undef COMMAND -#undef COMMANDS /** * The log function of dss. @@ -90,23 +228,32 @@ 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; struct tm *tm; time_t t1; char str[255] = ""; + int lpr_ll = lpr? OPT_UINT32_VAL(DSS, LOGLEVEL) : WARNING; - if (ll < conf.loglevel_arg) + if (loglevel < lpr_ll) return; outfd = logfile? logfile : stderr; - time(&t1); - tm = localtime(&t1); - strftime(str, sizeof(str), "%b %d %H:%M:%S", tm); - fprintf(outfd, "%s ", str); - if (conf.loglevel_arg <= INFO) - fprintf(outfd, "%i: ", ll); + if (subcmd == CMD_PTR(RUN)) { + time(&t1); + tm = localtime(&t1); + strftime(str, sizeof(str), "%b %d %H:%M:%S", tm); + fprintf(outfd, "%s ", str); + if (lpr_ll <= INFO) + fprintf(outfd, "%i: ", loglevel); + } + if (subcmd == CMD_PTR(RUN)) +#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); @@ -117,125 +264,345 @@ __printf_2_3 void dss_log(int ll, const char* fmt,...) */ static __printf_1_2 void dss_msg(const char* fmt,...) { - FILE *outfd = conf.daemon_given? logfile : stdout; + FILE *outfd = logfile? logfile : stdout; va_list argp; va_start(argp, fmt); vfprintf(outfd, fmt, argp); 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 (OPT_GIVEN(DSS, CONFIG_FILE)) + return dss_strdup(OPT_STRING_VAL(DSS, CONFIG_FILE)); + home = get_homedir(); + config_file = make_message("%s/.dssrc", home); + free(home); + return config_file; +} + +static int send_signal(int sig, bool wait) +{ + pid_t pid; + char *config_file = get_config_file_name(); + int ret = get_dss_pid(config_file, &pid); + unsigned ms = 32; + struct timespec ts; + 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) + if (OPT_GIVEN(DSS, DRY_RUN)) { + dss_msg("%d\n", (int)pid); + return 0; + } + DSS_NOTICE_LOG(("sending signal %d to pid %d\n", sig, (int)pid)); + ret = kill(pid, sig); + if (ret < 0) + return -ERRNO_TO_DSS_ERROR(errno); + if (!wait) + return 1; + while (ms < 5000) { + ts.tv_sec = ms / 1000; + ts.tv_nsec = (ms % 1000) * 1000 * 1000; + ret = nanosleep(&ts, NULL); + if (ret < 0) + return -ERRNO_TO_DSS_ERROR(errno); + ret = kill(pid, 0); + if (ret < 0) { + if (errno != ESRCH) + return -ERRNO_TO_DSS_ERROR(errno); return 1; - return 0; + } + ms *= 2; + } + return -E_KILL_TIMEOUT; +} + +struct signal_info { + const char * const name; + int num; +}; + +/* + * The table below was taken 2016 from proc/sig.c of procps-3.2.8. Copyright + * 1998-2003 by Albert Cahalan, GPLv2. + */ +static const struct signal_info signal_table[] = { + {"ABRT", SIGABRT}, /* IOT */ + {"ALRM", SIGALRM}, + {"BUS", SIGBUS}, + {"CHLD", SIGCHLD}, /* CLD */ + {"CONT", SIGCONT}, + {"FPE", SIGFPE}, + {"HUP", SIGHUP}, + {"ILL", SIGILL}, + {"INT", SIGINT}, + {"KILL", SIGKILL}, + {"PIPE", SIGPIPE}, +#ifdef SIGPOLL + {"POLL", SIGPOLL}, /* IO */ +#endif + {"PROF", SIGPROF}, +#ifdef SIGPWR + {"PWR", SIGPWR}, +#endif + {"QUIT", SIGQUIT}, + {"SEGV", SIGSEGV}, +#ifdef SIGSTKFLT + {"STKFLT", SIGSTKFLT}, +#endif + {"STOP", SIGSTOP}, + {"SYS", SIGSYS}, /* UNUSED */ + {"TERM", SIGTERM}, + {"TRAP", SIGTRAP}, + {"TSTP", SIGTSTP}, + {"TTIN", SIGTTIN}, + {"TTOU", SIGTTOU}, + {"URG", SIGURG}, + {"USR1", SIGUSR1}, + {"USR2", SIGUSR2}, + {"VTALRM", SIGVTALRM}, + {"WINCH", SIGWINCH}, + {"XCPU", SIGXCPU}, + {"XFSZ", SIGXFSZ} +}; + +#define SIGNAL_TABLE_SIZE (sizeof(signal_table) / sizeof(signal_table[0])) +#ifndef SIGRTMAX +#define SIGRTMAX 64 +#endif + +static int com_kill(void) +{ + bool w_given = OPT_GIVEN(KILL, WAIT); + const char *arg = OPT_STRING_VAL(KILL, SIGNAL); + int ret, i; + + if (*arg >= '0' && *arg <= '9') { + int64_t val; + ret = dss_atoi64(arg, &val); + if (ret < 0) + return ret; + if (val < 0 || val > SIGRTMAX) + return -ERRNO_TO_DSS_ERROR(EINVAL); + return send_signal(val, w_given); + } + if (strncasecmp(arg, "sig", 3) == 0) + arg += 3; + if (strcasecmp(arg, "CLD") == 0) + return send_signal(SIGCHLD, w_given); + if (strcasecmp(arg, "IOT") == 0) + return send_signal(SIGABRT, w_given); + for (i = 0; i < SIGNAL_TABLE_SIZE; i++) + if (strcasecmp(arg, signal_table[i].name) == 0) + return send_signal(signal_table[i].num, w_given); + DSS_ERROR_LOG(("invalid sigspec: %s\n", arg)); + return -ERRNO_TO_DSS_ERROR(EINVAL); } +EXPORT_CMD_HANDLER(kill); static void dss_get_snapshot_list(struct snapshot_list *sl) { - get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg); + get_snapshot_list(sl, OPT_UINT32_VAL(DSS, UNIT_INTERVAL), + OPT_UINT32_VAL(DSS, NUM_INTERVALS)); } -static void compute_next_snapshot_time(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; - unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg), - num_complete_snapshots = 0; - int i, ret; + int64_t x = 0, now = get_current_time(), unit_interval + = 24 * 3600 * OPT_UINT32_VAL(DSS, UNIT_INTERVAL), ret, + last_completion_time; + unsigned wanted = desired_number_of_snapshots(0, + OPT_UINT32_VAL(DSS, NUM_INTERVALS)), + num_complete = 0; + int i; struct snapshot *s = NULL; struct snapshot_list sl; - assert(snapshot_creation_status == SCS_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; + last_completion_time = s->completion_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 */ - gettimeofday(&now, NULL); - if (ret < 0 || !s) - goto min_sleep; - tv_divide(wanted, &diff, &tmp); /* sleep time betweeen two snapshots */ - diff.tv_sec = s->completion_time; - diff.tv_usec = 0; - tv_add(&diff, &tmp, &next_snapshot_time); - if (tv_diff(&now, &next_snapshot_time, NULL) < 0) + + 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; -min_sleep: - next_snapshot_time = now; - next_snapshot_time.tv_sec += 60; + ret = last_completion_time + unit_interval / wanted - x; out: free_snapshot_list(&sl); + 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 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", OPT_STRING_VAL(DSS, PRE_CREATE_HOOK))); + dss_exec_cmdline_pid(&create_pid, OPT_STRING_VAL(DSS, PRE_CREATE_HOOK)); + snapshot_creation_status = HS_PRE_RUNNING; } +static void pre_remove_hook(struct snapshot *s, const char *why) +{ + char *cmd; + + if (!s) + 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); + + snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot)); + *snapshot_currently_being_removed = *s; + snapshot_currently_being_removed->name = dss_strdup(s->name); + + cmd = make_message("%s %s/%s", OPT_STRING_VAL(DSS, PRE_REMOVE_HOOK), + OPT_STRING_VAL(DSS, DEST_DIR), s->name); + DSS_DEBUG_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&remove_pid, cmd); + free(cmd); + snapshot_removal_status = HS_PRE_RUNNING; +} -static int remove_snapshot(struct snapshot *s) +static int exec_rm(void) { - int fds[3] = {0, 0, 0}; - assert(!rm_pid); + struct snapshot *s = snapshot_currently_being_removed; char *new_name = being_deleted_name(s); - int ret = dss_rename(s->name, new_name); - 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)); + ret = dss_rename(s->name, new_name); if (ret < 0) goto out; - DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval); - ret = dss_exec(&rm_pid, argv[0], argv, fds); + dss_exec(&remove_pid, argv[0], argv); + snapshot_removal_status = HS_RUNNING; out: free(new_name); return ret; } +static int snapshot_is_being_created(struct snapshot *s) +{ + return s->creation_time == current_snapshot_creation_time; +} + +static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl) +{ + struct snapshot *s; + int i; + + DSS_DEBUG_LOG(("looking for old incomplete snapshots\n")); + FOR_EACH_SNAPSHOT(s, i, sl) { + if (snapshot_is_being_created(s)) + continue; + /* + * We know that no rm is currently running, so if s is marked + * as being deleted, a previously started rm must have failed. + */ + if (s->flags & SS_BEING_DELETED) + return s; + + if (s->flags & SS_COMPLETE) /* good snapshot */ + continue; + /* + * This snapshot is incomplete and it is not the snapshot + * currently being created. However, we must not remove it if + * rsync is about to be restarted. As only the newest snapshot + * can be restarted, this snapshot is orphaned if it is not the + * newest snapshot or if we are not about to restart rsync. + */ + if (get_newest_snapshot(sl) != s) + return s; + if (snapshot_creation_status != HS_NEEDS_RESTART) + return s; + } + /* no orphaned snapshots */ + return NULL; +} + +static int is_reference_snapshot(struct snapshot *s) +{ + if (!name_of_reference_snapshot) + return 0; + return strcmp(s->name, name_of_reference_snapshot)? 0 : 1; +} + /* * return: 0: no redundant snapshots, 1: rm process started, negative: error */ -static int remove_redundant_snapshot(struct snapshot_list *sl) +static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl) { - int ret, i, interval; + int i, interval; struct snapshot *s; unsigned missing = 0; + uint32_t N = OPT_UINT32_VAL(DSS, NUM_INTERVALS); - 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); + DSS_DEBUG_LOG(("looking for intervals containing too many snapshots\n")); + for (interval = N - 1; interval >= 0; interval--) { + unsigned keep = desired_number_of_snapshots(interval, N); unsigned num = sl->interval_count[interval]; struct snapshot *victim = NULL, *prev = NULL; int64_t score = LONG_MAX; 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 */ FOR_EACH_SNAPSHOT(s, i, sl) { int64_t this_score; - //DSS_DEBUG_LOG("checking %s\n", s->name); + if (snapshot_is_being_created(s)) + continue; + if (is_reference_snapshot(s)) + continue; if (s->interval > interval) { prev = s; continue; @@ -251,7 +618,6 @@ static int remove_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; @@ -259,183 +625,238 @@ static int remove_redundant_snapshot(struct snapshot_list *sl) prev = s; } assert(victim); - if (conf.dry_run_given) { - dss_msg("%s would be removed (interval = %i)\n", - victim->name, victim->interval); - continue; - } - ret = remove_snapshot(victim); - return ret < 0? ret : 1; + return victim; } - return 0; + return NULL; } -static int remove_outdated_snapshot(struct snapshot_list *sl) +static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl) { - int i, ret; + 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", + OPT_UINT32_VAL(DSS, NUM_INTERVALS))); FOR_EACH_SNAPSHOT(s, i, sl) { - if (s->interval <= conf.num_intervals_arg) + if (snapshot_is_being_created(s)) continue; - if (conf.dry_run_given) { - dss_msg("%s would be removed (interval = %i)\n", - s->name, s->interval); + if (is_reference_snapshot(s)) continue; - } - ret = remove_snapshot(s); - if (ret < 0) - return ret; - return 1; + if (s->interval < OPT_UINT32_VAL(DSS, NUM_INTERVALS)) + continue; + return s; } - return 0; + return NULL; } -static int remove_oldest_snapshot(struct snapshot_list *sl) +static struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl) { - struct snapshot *s = get_oldest_snapshot(sl); + int i, num_complete; + struct snapshot *s, *ref = NULL; - if (!s) /* no snapshot found */ - return 0; - DSS_INFO_LOG("oldest snapshot: %s\n", s->name); - if (s->creation_time == current_snapshot_creation_time) - return 0; /* do not remove the snapshot currently being created */ - return remove_snapshot(s); + num_complete = num_complete_snapshots(sl); + if (num_complete <= OPT_UINT32_VAL(DSS, MIN_COMPLETE)) + return NULL; + FOR_EACH_SNAPSHOT(s, i, sl) { + if (snapshot_is_being_created(s)) + continue; + if (is_reference_snapshot(s)) { /* avoid this one */ + ref = s; + continue; + } + DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name)); + return s; + } + 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; } -static int try_to_free_disk_space(int low_disk_space) +static int try_to_free_disk_space(void) { int ret; struct snapshot_list sl; + struct snapshot *victim; + struct timeval now; + const char *why; + int low_disk_space; - if (!low_disk_space && conf.keep_redundant_given) + 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) { + if (OPT_GIVEN(DSS, KEEP_REDUNDANT)) + 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 = remove_outdated_snapshot(&sl); - if (ret) /* error, or we are removing something */ - goto out; - /* no outdated snapshot */ - ret = remove_redundant_snapshot(&sl); - if (ret) - goto out; ret = 0; - if (!low_disk_space) + /* + * 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 << OPT_UINT32_VAL(DSS, NUM_INTERVALS)) goto out; - DSS_WARNING_LOG("disk space low and nothing obvious to remove\n"); - ret = remove_oldest_snapshot(&sl); - if (ret) + why = "outdated"; + victim = find_outdated_snapshot(&sl); + if (victim) + goto remove; + why = "redundant"; + victim = find_redundant_snapshot(&sl); + if (victim) + goto remove; + why = "orphaned"; + victim = find_orphaned_snapshot(&sl); + if (victim) + goto remove; + /* try harder only if disk space is low */ + if (!low_disk_space) goto out; - DSS_CRIT_LOG("uhuhu: not enough disk space for a single snapshot\n"); + DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n")); + why = "oldest"; + victim = find_oldest_removable_snapshot(&sl); + if (victim) + goto remove; + DSS_CRIT_LOG(("uhuhu: disk space low and nothing to remove\n")); ret = -ERRNO_TO_DSS_ERROR(ENOSPC); + goto out; +remove: + pre_remove_hook(victim, why); out: free_snapshot_list(&sl); return ret; } -static int pre_create_hook(void) +static void post_create_hook(void) { - int ret, fds[3] = {0, 0, 0}; - - if (!conf.pre_create_hook_given) { - 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, - conf.pre_create_hook_arg, fds); - if (ret < 0) - return ret; - snapshot_creation_status = SCS_PRE_HOOK_RUNNING; - return ret; + char *cmd = make_message("%s %s/%s", + OPT_STRING_VAL(DSS, POST_CREATE_HOOK), + OPT_STRING_VAL(DSS, DEST_DIR), path_to_last_complete_snapshot); + DSS_NOTICE_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&create_pid, cmd); + free(cmd); + snapshot_creation_status = HS_POST_RUNNING; } -static int post_create_hook(void) +static void post_remove_hook(void) { - int ret, fds[3] = {0, 0, 0}; char *cmd; + struct snapshot *s = snapshot_currently_being_removed; - if (!conf.post_create_hook_given) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); - return 0; - } - cmd = make_message("%s %s", conf.post_create_hook_arg, - path_to_last_complete_snapshot); - DSS_NOTICE_LOG("executing %s\n", cmd); - ret = dss_exec_cmdline_pid(&post_create_hook_pid, cmd, fds); + assert(s); + + cmd = make_message("%s %s/%s", OPT_STRING_VAL(DSS, POST_REMOVE_HOOK), + OPT_STRING_VAL(DSS, DEST_DIR), s->name); + DSS_NOTICE_LOG(("executing %s\n", cmd)); + dss_exec_cmdline_pid(&remove_pid, cmd); free(cmd); - if (ret < 0) - return ret; - snapshot_creation_status = SCS_POST_HOOK_RUNNING; - return ret; + snapshot_removal_status = HS_POST_RUNNING; } -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_rsync_process(void) +static void stop_create_process(void) { - if (!rsync_pid || rsync_stopped) + if (create_process_stopped) return; - kill(SIGSTOP, rsync_pid); - rsync_stopped = 1; + dss_kill(create_pid, SIGSTOP, "suspending create process"); + create_process_stopped = 1; } -static void restart_rsync_process(void) +static void restart_create_process(void) { - if (!rsync_pid || !rsync_stopped) + if (!create_process_stopped) return; - kill (SIGCONT, rsync_pid); - rsync_stopped = 0; + dss_kill(create_pid, SIGCONT, "resuming create process"); + create_process_stopped = 0; } - /** * Print a log message about the exit status of a child. */ 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; @@ -457,33 +878,89 @@ 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; } +static void handle_pre_remove_exit(int status) +{ + if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { + snapshot_removal_status = HS_READY; + gettimeofday(&next_removal_check, NULL); + next_removal_check.tv_sec += 60; + return; + } + snapshot_removal_status = HS_PRE_SUCCESS; +} + static int handle_rm_exit(int status) { - rm_pid = 0; - if (!WIFEXITED(status)) + if (!WIFEXITED(status)) { + snapshot_removal_status = HS_READY; return -E_INVOLUNTARY_EXIT; - if (WEXITSTATUS(status)) + } + if (WEXITSTATUS(status)) { + snapshot_removal_status = HS_READY; return -E_BAD_EXIT_CODE; + } + snapshot_removal_status = HS_SUCCESS; return 1; } -static int wait_for_rm_process(void) +static void handle_post_remove_exit(void) +{ + snapshot_removal_status = HS_READY; +} + +static int handle_remove_exit(int status) { - int status, ret = wait_for_process(rm_pid, &status); + int ret; + struct snapshot *s = snapshot_currently_being_removed; + + assert(s); + switch (snapshot_removal_status) { + case HS_PRE_RUNNING: + handle_pre_remove_exit(status); + ret = 1; + break; + case HS_RUNNING: + ret = handle_rm_exit(status); + break; + case HS_POST_RUNNING: + handle_post_remove_exit(); + ret = 1; + break; + default: + ret = -E_BUG; + } + if (snapshot_removal_status == HS_READY) { + free(s->name); + free(s); + snapshot_currently_being_removed = NULL; + } + remove_pid = 0; + return ret; +} +static int wait_for_remove_process(void) +{ + int status, ret; + + assert(remove_pid); + assert( + snapshot_removal_status == HS_PRE_RUNNING || + snapshot_removal_status == HS_RUNNING || + snapshot_removal_status == HS_POST_RUNNING + ); + ret = wait_for_process(remove_pid, &status); if (ret < 0) return ret; - return handle_rm_exit(status); + return handle_remove_exit(status); } static int handle_rsync_exit(int status) @@ -491,60 +968,74 @@ 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(); + snapshot_creation_status = HS_READY; 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; - gettimeofday(&next_snapshot_time, NULL); - next_snapshot_time.tv_sec += 60; + /* + * Restart rsync on non-fatal errors: + * 24: Partial transfer due to vanished source files + */ + if (es != 0 && es != 24) { + DSS_WARNING_LOG(("rsync exit code %d, error count %d\n", + es, ++num_consecutive_rsync_errors)); + if (!logfile) { /* called by com_run() */ + ret = -E_BAD_EXIT_CODE; + goto out; + } + if (num_consecutive_rsync_errors > + OPT_UINT32_VAL(RUN, MAX_RSYNC_ERRORS)) { + 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; + 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)rsync_pid, es); - ret = -E_BAD_EXIT_CODE; - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); - goto out; - } + num_consecutive_rsync_errors = 0; ret = rename_incomplete_snapshot(current_snapshot_creation_time); if (ret < 0) goto out; - snapshot_creation_status = SCS_RSYNC_SUCCESS; + snapshot_creation_status = HS_SUCCESS; + free(name_of_reference_snapshot); + name_of_reference_snapshot = NULL; out: - rsync_pid = 0; - rsync_stopped = 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; - compute_next_snapshot_time(); + snapshot_creation_status = HS_READY; ret = -E_INVOLUNTARY_EXIT; goto out; } es = WEXITSTATUS(status); if (es) { - snapshot_creation_status = SCS_READY; - compute_next_snapshot_time(); - ret = -E_BAD_EXIT_CODE; + if (!warn_count--) { + DSS_NOTICE_LOG(("pre_create_hook %s returned %d\n", + OPT_STRING_VAL(DSS, PRE_CREATE_HOOK), es)); + DSS_NOTICE_LOG(("deferring snapshot creation...\n")); + warn_count = 60; /* warn only once per hour */ + } + next_snapshot_time = get_current_time() + 60; + snapshot_creation_status = HS_READY; + 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; return ret; } @@ -555,116 +1046,249 @@ 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: + ret = handle_pre_create_hook_exit(status); + break; + case HS_RUNNING: + ret = handle_rsync_exit(status); + break; + case HS_POST_RUNNING: + snapshot_creation_status = HS_READY; + 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; } - DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid); + if (pid == remove_pid) { + ret = handle_remove_exit(status); + if (ret < 0) + return ret; + return ret; + } + DSS_EMERG_LOG(("BUG: unknown process %d died\n", (int)pid)); return -E_BUG; } +/* also checks if . is a mountpoint, if --mountpoint was given */ +static int change_to_dest_dir(void) +{ + int ret; + const char *dd = OPT_STRING_VAL(DSS, DEST_DIR); + struct stat dot, dotdot; + + DSS_INFO_LOG(("changing cwd to %s\n", dd)); + if (chdir(dd) < 0) { + ret = -ERRNO_TO_DSS_ERROR(errno); + DSS_ERROR_LOG(("could not change cwd to %s\n", dd)); + return ret; + } + if (!OPT_GIVEN(DSS, MOUNTPOINT)) + return 0; + if (stat(".", &dot) < 0) { + ret = -ERRNO_TO_DSS_ERROR(errno); + DSS_ERROR_LOG(("could not stat .\n")); + return ret; + } + if (stat("..", &dotdot) < 0) { + ret = -ERRNO_TO_DSS_ERROR(errno); + DSS_ERROR_LOG(("could not stat ..\n")); + return ret; + } + if (dot.st_dev == dotdot.st_dev && dot.st_ino != dotdot.st_ino) { + DSS_ERROR_LOG(("mountpoint check failed for %s\n", dd)); + return -E_MOUNTPOINT; + } + return 1; +} + static int check_config(void) { - if (conf.unit_interval_arg <= 0) { - DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg); + int ret; + uint32_t unit_interval = OPT_UINT32_VAL(DSS, UNIT_INTERVAL); + uint32_t num_intervals = OPT_UINT32_VAL(DSS, NUM_INTERVALS); + + if (unit_interval == 0) { + DSS_ERROR_LOG(("bad unit interval: %i\n", unit_interval)); 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", unit_interval)); + + if (num_intervals == 0 || num_intervals > 30) { + DSS_ERROR_LOG(("bad number of intervals: %i\n", num_intervals)); return -E_INVALID_NUMBER; } - DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg); + if (subcmd == CMD_PTR(RUN) || subcmd == CMD_PTR(CREATE)) + if (!OPT_GIVEN(DSS, SOURCE_DIR)) { + DSS_ERROR_LOG(("--source-dir required\n")); + return -E_SYNTAX; + } + if (subcmd == CMD_PTR(RUN) || subcmd == CMD_PTR(CREATE) + || subcmd == CMD_PTR(LS) || subcmd == CMD_PTR(PRUNE)) { + if (!OPT_GIVEN(DSS, DEST_DIR)) { + DSS_ERROR_LOG(("--dest-dir required\n")); + return -E_SYNTAX; + } + ret = change_to_dest_dir(); + if (ret < 0) + return ret; + } + DSS_DEBUG_LOG(("number of intervals: %i\n", num_intervals)); return 1; } -static int parse_config_file(int override) +static int lopsub_error(int lopsub_ret, char **errctx) { - int ret; - char *config_file; + const char *msg = lls_strerror(-lopsub_ret); + if (*errctx) + DSS_ERROR_LOG(("%s: %s\n", *errctx, msg)); + else + DSS_ERROR_LOG(("%s\n", msg)); + free(*errctx); + *errctx = NULL; + return -E_LOPSUB; +} + +static int parse_config_file(bool sighup, const struct lls_command *cmd) +{ + int ret, fd = -1; + 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); + void *map; + size_t sz; + int cf_argc; + char **cf_argv, *errctx = NULL; + struct lls_parse_result *cf_lpr, *merged_lpr, *clpr; + const char *subcmd_name; + + ret = open(config_file, O_RDONLY); + if (ret < 0) { + if (errno != ENOENT || OPT_GIVEN(DSS, CONFIG_FILE)) { + ret = -ERRNO_TO_DSS_ERROR(errno); + DSS_ERROR_LOG(("config file %s can not be opened\n", + config_file)); + goto out; + } + /* no config file -- nothing to do */ + ret = 0; + goto success; } - if (override) { /* SIGHUP */ - if (conf.logfile_given) - old_logfile_arg = dss_strdup(conf.logfile_arg); - old_daemon_given = conf.daemon_given; + fd = ret; + ret = fstat(fd, &statbuf); + if (ret < 0) { + ret = -ERRNO_TO_DSS_ERROR(errno); + DSS_ERROR_LOG(("failed to stat config file %s\n", config_file)); + goto close_fd; } - - ret = stat(config_file, &statbuf); - if (ret && conf.config_file_given) { + sz = statbuf.st_size; + if (sz == 0) { /* config file is empty -- nothing to do */ + ret = 0; + goto success; + } + map = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, fd, 0); + if (map == MAP_FAILED) { ret = -ERRNO_TO_DSS_ERROR(errno); - DSS_ERROR_LOG("failed to stat config file %s\n", config_file); - goto out; + DSS_ERROR_LOG(("failed to mmap config file %s\n", + config_file)); + goto close_fd; + } + if (cmd == CMD_PTR(DSS)) + subcmd_name = NULL; + else + subcmd_name = lls_command_name(cmd); + ret = lls_convert_config(map, sz, subcmd_name, &cf_argv, &errctx); + munmap(map, sz); + if (ret < 0) { + DSS_ERROR_LOG(("failed to convert config file %s\n", + config_file)); + ret = lopsub_error(ret, &errctx); + goto close_fd; } - if (!ret) { - struct cmdline_parser_params params = { - .override = override, - .initialize = 0, - .check_required = 1, - .check_ambiguity = 0, - .print_errors = 1 - }; - cmdline_parser_config_file(config_file, &conf, ¶ms); + cf_argc = ret; + ret = lls_parse(cf_argc, cf_argv, cmd, &cf_lpr, &errctx); + lls_free_argv(cf_argv); + if (ret < 0) { + ret = lopsub_error(ret, &errctx); + goto close_fd; } - ret = check_config(); - if (ret < 0) - goto out; - if (override) { - /* don't change daemon mode on SIGHUP */ - conf.daemon_given = old_daemon_given; - close_log(logfile); - logfile = NULL; - if (conf.logfile_given) - free(old_logfile_arg); - else if (conf.daemon_given) { /* re-use old logfile */ - conf.logfile_arg = old_logfile_arg; - conf.logfile_given = 1; - } + clpr = cmd == CMD_PTR(DSS)? cmdline_lpr : cmdline_sublpr; + if (sighup) /* config file overrides command line */ + ret = lls_merge(cf_lpr, clpr, cmd, &merged_lpr, &errctx); + else /* command line options overrride config file options */ + ret = lls_merge(clpr, cf_lpr, cmd, &merged_lpr, &errctx); + lls_free_parse_result(cf_lpr, cmd); + if (ret < 0) { + ret = lopsub_error(ret, &errctx); + goto close_fd; } - if (conf.logfile_given) { - logfile = open_log(conf.logfile_arg); - log_welcome(conf.loglevel_arg); + ret = 1; +success: + assert(ret >= 0); + DSS_DEBUG_LOG(("loglevel: %d\n", OPT_UINT32_VAL(DSS, LOGLEVEL))); + if (cmd != CMD_PTR(DSS)) { + if (ret > 0) { + if (sublpr != cmdline_sublpr) + lls_free_parse_result(sublpr, cmd); + sublpr = merged_lpr; + } else + sublpr = cmdline_sublpr; + } else { + if (ret > 0) { + if (lpr != cmdline_lpr) + lls_free_parse_result(lpr, cmd); + lpr = merged_lpr; + } else + lpr = cmdline_lpr; } - DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg); -// cmdline_parser_dump(logfile? logfile : stdout, &conf); +close_fd: + if (fd >= 0) + close(fd); 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); - return dss_chdir(conf.dest_dir_arg); -} - 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 */, CMD_PTR(DSS)); + if (ret < 0) + return ret; + ret = parse_config_file(true /* SIGHUP */, CMD_PTR(RUN)); if (ret < 0) return ret; - return change_to_dest_dir(); + ret = check_config(); + if (ret < 0) + return ret; + close_log(logfile); + logfile = NULL; + if (OPT_GIVEN(RUN, DAEMON) || daemonized) { + logfile = open_log(OPT_STRING_VAL(RUN, LOGFILE)); + log_welcome(OPT_UINT32_VAL(DSS, LOGLEVEL)); + daemonized = true; + } + dump_dss_config("reloaded"); + invalidate_next_snapshot_time(); + return 1; +} + +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) @@ -677,11 +1301,7 @@ static int handle_signal(void) switch (sig) { case SIGINT: case SIGTERM: - restart_rsync_process(); - kill_process(rsync_pid); - kill_process(rm_pid); - ret = -E_SIGNAL; - break; + return -E_SIGNAL; case SIGHUP: ret = handle_sighup(); break; @@ -691,45 +1311,126 @@ 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; +} + +/* + * We can not use rsync locally if the local user is different from the remote + * user or if the src dir is not on the local host (or both). + */ +static int use_rsync_locally(char *logname) +{ + const char *h = OPT_STRING_VAL(DSS, REMOTE_HOST); + + if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1")) + return 0; + if (OPT_GIVEN(DSS, REMOTE_USER) && + strcmp(OPT_STRING_VAL(DSS, REMOTE_USER), logname)) + return 0; + 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; + 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_NOTICE_LOG(("recycling %s snapshot %s\n", why, s->name)); + ret = dss_rename(s->name, new_name); + } + if (ret >= 0) + DSS_NOTICE_LOG(("creating %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, *newest; - int i = 0, j; + char *logname; + int i = 0, j, N = OPT_GIVEN(DSS, RSYNC_OPTION); struct snapshot_list sl; + static bool seeded; dss_get_snapshot_list(&sl); - newest = name_of_newest_complete_snapshot(&sl); + assert(!name_of_reference_snapshot); + name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl); free_snapshot_list(&sl); - *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *)); + *argv = dss_malloc((15 + N) * 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 (newest) { - DSS_INFO_LOG("using %s as reference snapshot\n", newest); - (*argv)[i++] = make_message("--link-dest=../%s", newest); - free(newest); + if (!seeded) { + srandom((unsigned)time(NULL)); /* no need to be fancy here */ + seeded = true; + } + if (1000 * (random() / (RAND_MAX + 1.0)) < OPT_UINT32_VAL(DSS, CHECKSUM)) { + DSS_NOTICE_LOG(("adding --checksum to rsync options\n")); + (*argv)[i++] = dss_strdup("--checksum"); + } + for (j = 0; j < N; j++) + (*argv)[i++] = dss_strdup(lls_string_val(j, + OPT_RESULT(DSS, RSYNC_OPTION))); + if (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 previous snapshot found\n"); + DSS_INFO_LOG(("no suitable reference snapshot found\n")); logname = dss_logname(); - if (conf.remote_user_given && !strcmp(conf.remote_user_arg, logname)) - (*argv)[i++] = dss_strdup(conf.source_dir_arg); + if (use_rsync_locally(logname)) + (*argv)[i++] = dss_strdup(OPT_STRING_VAL(DSS, SOURCE_DIR)); else - (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given? - conf.remote_user_arg : logname, - conf.remote_host_arg, conf.source_dir_arg); + (*argv)[i++] = make_message("%s@%s:%s/", + OPT_GIVEN(DSS, REMOTE_USER)? + OPT_STRING_VAL(DSS, REMOTE_USER) : logname, + OPT_STRING_VAL(DSS, REMOTE_HOST), + OPT_STRING_VAL(DSS, SOURCE_DIR)); free(logname); *num = get_current_time(); (*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) @@ -745,16 +1446,14 @@ 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(&rsync_pid, argv[0], argv, fds); + assert(argv); + ret = rename_resume_snap(current_snapshot_creation_time); if (ret < 0) return ret; - snapshot_creation_status = SCS_RSYNC_RUNNING; + dss_exec(&create_pid, argv[0], argv); + snapshot_creation_status = HS_RUNNING; return ret; } @@ -767,11 +1466,10 @@ static int select_loop(void) for (;;) { fd_set rfds; - int low_disk_space; - struct timeval now, *tvp; + struct timeval *tvp; - if (rm_pid) - tvp = NULL; /* sleep until rm process dies */ + if (remove_pid) + tvp = NULL; /* sleep until rm hook/process dies */ else { /* sleep one minute */ tv.tv_sec = 60; tv.tv_usec = 0; @@ -779,7 +1477,6 @@ 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; @@ -788,51 +1485,54 @@ static int select_loop(void) if (ret < 0) goto out; } - if (rm_pid) + if (remove_pid) continue; - ret = disk_space_low(); - if (ret < 0) - goto out; - low_disk_space = ret; - ret = try_to_free_disk_space(low_disk_space); + if (snapshot_removal_status == HS_PRE_SUCCESS) { + ret = exec_rm(); + if (ret < 0) + goto out; + continue; + } + if (snapshot_removal_status == HS_SUCCESS) { + post_remove_hook(); + continue; + } + ret = try_to_free_disk_space(); if (ret < 0) goto out; - if (rm_pid) { - stop_rsync_process(); + if (snapshot_removal_status != HS_READY) { + stop_create_process(); continue; } - restart_rsync_process(); - gettimeofday(&now, NULL); - if (tv_diff(&next_snapshot_time, &now, NULL) > 0) - continue; + restart_create_process(); switch (snapshot_creation_status) { - case SCS_READY: - ret = pre_create_hook(); - if (ret < 0) - goto out; + case HS_READY: + if (!next_snapshot_is_due()) + continue; + pre_create_hook(); continue; - case SCS_PRE_HOOK_RUNNING: + case HS_PRE_RUNNING: + case HS_RUNNING: + case HS_POST_RUNNING: continue; - case SCS_RSYNC_NEEDS_RESTART: + case HS_PRE_SUCCESS: + 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 SCS_PRE_HOOK_SUCCESS: - free_rsync_argv(rsync_argv); - create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); + case HS_NEEDS_RESTART: + if (!next_snapshot_is_due()) + continue; ret = create_snapshot(rsync_argv); if (ret < 0) goto out; continue; - case SCS_RSYNC_RUNNING: - continue; - case SCS_RSYNC_SUCCESS: - ret = post_create_hook(); - if (ret < 0) - goto out; - continue; - case SCS_POST_HOOK_RUNNING: + case HS_SUCCESS: + post_create_hook(); continue; } } @@ -842,80 +1542,147 @@ 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}; pid_t pid; + char **argv, *tmp = dss_strdup(OPT_STRING_VAL(DSS, EXIT_HOOK)); + unsigned n = split_args(tmp, &argv, " \t"); + + n++; + argv = dss_realloc(argv, (n + 1) * sizeof(char *)); + argv[n - 1] = dss_strdup(dss_strerror(-exit_code)); + argv[n] = NULL; + dss_exec(&pid, argv[0], argv); + free(argv[n - 1]); + free(argv); + free(tmp); +} - 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); +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; + int ret, fd = -1; + char *config_file; + pid_t pid; - if (conf.dry_run_given) { - DSS_ERROR_LOG("dry_run not supported by this command\n"); + if (OPT_GIVEN(DSS, DRY_RUN)) { + DSS_ERROR_LOG(("dry run not supported by this command\n")); return -E_SYNTAX; } + config_file = get_config_file_name(); + ret = get_dss_pid(config_file, &pid); + free(config_file); + if (ret >= 0) { + DSS_ERROR_LOG(("pid %d\n", (int)pid)); + return -E_ALREADY_RUNNING; + } + if (OPT_GIVEN(RUN, DAEMON)) { + fd = daemon_init(); + daemonized = true; + logfile = open_log(OPT_STRING_VAL(RUN, LOGFILE)); + } + lock_dss_or_die(); + dump_dss_config("startup"); ret = install_sighandler(SIGHUP); if (ret < 0) return ret; - compute_next_snapshot_time(); + if (fd >= 0) { + ret = write(fd, "\0", 1); + if (ret != 1) { + DSS_ERROR_LOG(("write to daemon pipe returned %d\n", + ret)); + if (ret < 0) + return -ERRNO_TO_DSS_ERROR(errno); + return -E_BUG; + } + } ret = select_loop(); if (ret >= 0) /* impossible */ ret = -E_BUG; + kill_children(); exit_hook(ret); + while (wait(NULL) >= 0 || errno != ECHILD) + ; /* still have children to wait for */ return ret; } +EXPORT_CMD_HANDLER(run); static int com_prune(void) { int ret; struct snapshot_list sl; + struct snapshot *victim; struct disk_space ds; + const char *why; + lock_dss_or_die(); ret = get_disk_space(".", &ds); if (ret < 0) return ret; log_disk_space(&ds); - for (;;) { - dss_get_snapshot_list(&sl); - ret = remove_outdated_snapshot(&sl); - free_snapshot_list(&sl); - if (ret < 0) - return ret; - if (!ret) - break; - ret = wait_for_rm_process(); - if (ret < 0) - goto out; + dss_get_snapshot_list(&sl); + why = "outdated"; + victim = find_outdated_snapshot(&sl); + if (victim) + goto rm; + why = "redundant"; + victim = find_redundant_snapshot(&sl); + if (victim) + goto rm; + ret = 0; + goto out; +rm: + if (OPT_GIVEN(DSS, DRY_RUN)) { + dss_msg("%s snapshot %s (interval = %i)\n", + why, victim->name, victim->interval); + ret = 0; + goto out; } - for (;;) { - dss_get_snapshot_list(&sl); - ret = remove_redundant_snapshot(&sl); - free_snapshot_list(&sl); - if (ret < 0) - return ret; - if (!ret) - break; - ret = wait_for_rm_process(); + pre_remove_hook(victim, why); + if (snapshot_removal_status == HS_PRE_RUNNING) { + ret = wait_for_remove_process(); if (ret < 0) goto out; + if (snapshot_removal_status != HS_PRE_SUCCESS) + goto out; } - return 1; + ret = exec_rm(); + if (ret < 0) + goto out; + ret = wait_for_remove_process(); + if (ret < 0) + goto out; + if (snapshot_removal_status != HS_SUCCESS) + goto out; + post_remove_hook(); + if (snapshot_removal_status != HS_POST_RUNNING) + goto out; + ret = wait_for_remove_process(); + if (ret < 0) + goto out; + ret = 1; out: + free_snapshot_list(&sl); return ret; } +EXPORT_CMD_HANDLER(prune); static int com_create(void) { int ret, status; char **rsync_argv; - if (conf.dry_run_given) { + lock_dss_or_die(); + if (OPT_GIVEN(DSS, DRY_RUN)) { int i; char *msg = NULL; create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time); @@ -930,57 +1697,68 @@ static int com_create(void) free(msg); return 1; } - ret = pre_create_hook(); - if (ret < 0) - return ret; - if (pre_create_hook_pid) { - ret = wait_for_process(pre_create_hook_pid, &status); + pre_create_hook(); + 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; } +EXPORT_CMD_HANDLER(create); static int com_ls(void) { int i; struct snapshot_list sl; struct snapshot *s; + int64_t now = get_current_time(); dss_get_snapshot_list(&sl); FOR_EACH_SNAPSHOT(s, i, &sl) { - int64_t d = 0; + int64_t d; 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); - }; + else + d = (now - 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; } +EXPORT_CMD_HANDLER(ls); + +static int com_configtest(void) +{ + printf("Syntax Ok\n"); + return 0; +} +EXPORT_CMD_HANDLER(configtest); 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) @@ -991,38 +1769,94 @@ 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. - */ +static void handle_version_and_help(void) +{ + char *txt; + + if (OPT_GIVEN(DSS, DETAILED_HELP)) + txt = lls_long_help(CMD_PTR(DSS)); + else if (OPT_GIVEN(DSS, HELP)) + txt = lls_short_help(CMD_PTR(DSS)); + else if (OPT_GIVEN(DSS, VERSION)) + txt = make_message("%s\n", VERSION_STRING); + else + return; + printf("%s", txt); + free(txt); + exit(EXIT_SUCCESS); +} + +static void show_subcommand_summary(void) +{ + const struct lls_command *cmd; + int i; + + printf("Available subcommands:\n"); + for (i = 1; (cmd = lls_cmd(i, dss_suite)); i++) { + const char *name = lls_command_name(cmd); + const char *purpose = lls_purpose(cmd); + printf("%-11s%s\n", name, purpose); + } + exit(EXIT_SUCCESS); +} + 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 - }; + char *errctx = NULL; + unsigned num_inputs; + const struct dss_user_data *ud; - cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */ - ret = parse_config_file(0); + ret = lls_parse(argc, argv, CMD_PTR(DSS), &cmdline_lpr, &errctx); + if (ret < 0) { + ret = lopsub_error(ret, &errctx); + goto out; + } + lpr = cmdline_lpr; + ret = parse_config_file(false /* no SIGHUP */, CMD_PTR(DSS)); if (ret < 0) goto out; - if (conf.daemon_given) - daemon_init(); - ret = change_to_dest_dir(); + handle_version_and_help(); + num_inputs = lls_num_inputs(lpr); + if (num_inputs == 0) + show_subcommand_summary(); + ret = lls_lookup_subcmd(argv[argc - num_inputs], dss_suite, &errctx); + if (ret < 0) { + ret = lopsub_error(ret, &errctx); + goto out; + } + subcmd = lls_cmd(ret, dss_suite); + ret = lls_parse(num_inputs, argv + argc - num_inputs, subcmd, + &cmdline_sublpr, &errctx); + if (ret < 0) { + ret = lopsub_error(ret, &errctx); + goto out; + } + sublpr = cmdline_sublpr; + ret = parse_config_file(false /* no SIGHUP */, subcmd); + if (ret < 0) + goto out; + ret = check_config(); if (ret < 0) goto out; ret = setup_signal_handling(); if (ret < 0) goto out; - ret = call_command_handler(); + ud = lls_user_data(subcmd); + ret = ud->handler(); + signal_shutdown(); out: - if (ret < 0) - DSS_EMERG_LOG("%s\n", dss_strerror(-ret)); + if (ret < 0) { + if (errctx) + DSS_ERROR_LOG(("%s\n", errctx)); + DSS_EMERG_LOG(("%s\n", dss_strerror(-ret))); + } + free(errctx); + lls_free_parse_result(lpr, CMD_PTR(DSS)); + if (lpr != cmdline_lpr) + lls_free_parse_result(cmdline_lpr, CMD_PTR(DSS)); + lls_free_parse_result(sublpr, subcmd); + if (sublpr != cmdline_sublpr) + lls_free_parse_result(cmdline_sublpr, subcmd); exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE); }