/*
- * Copyright (C) 2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2008-2009 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
/** Process id of current pre-remove/rm/post-remove process. */
static pid_t remove_pid;
/** When the next snapshot is due. */
-static struct timeval next_snapshot_time;
+static int64_t next_snapshot_time;
/** When to try to remove something. */
static struct timeval next_removal_check;
/** Creation time of the snapshot currently being created. */
static int64_t current_snapshot_creation_time;
-/* The snapshot currently being removed. */
+/** The snapshot currently being removed. */
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. */
get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
}
-static int next_snapshot_is_due(void)
+static int64_t compute_next_snapshot_time(void)
{
- struct timeval now, unit_interval = {.tv_sec = 24 * 3600 * conf.unit_interval_arg},
- tmp, diff;
- int64_t x = 0;
+ int64_t x = 0, now = get_current_time(), unit_interval
+ = 24 * 3600 * conf.unit_interval_arg, ret;
unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
num_complete_snapshots = 0;
- int i, ret;
+ int i;
struct snapshot *s = NULL;
struct snapshot_list sl;
- gettimeofday(&now, NULL);
- if (tv_diff(&next_snapshot_time, &now, NULL) > 0)
- return 0;
- assert(snapshot_creation_status == HS_READY);
current_snapshot_creation_time = 0;
dss_get_snapshot_list(&sl);
FOR_EACH_SNAPSHOT(s, i, &sl) {
x += s->completion_time - s->creation_time;
}
assert(x >= 0);
- if (num_complete_snapshots)
- x /= num_complete_snapshots; /* avg time to create one snapshot */
- x *= wanted; /* time to create all snapshots in interval 0 */
- tmp.tv_sec = x;
- tmp.tv_usec = 0;
- ret = tv_diff(&unit_interval, &tmp, &diff); /* total sleep time per unit interval */
- if (ret < 0 || !s) { /* unit_interval < tmp or no snapshot */
- ret = 1;
- goto out;
- }
- tv_divide(wanted, &diff, &tmp); /* sleep time between two snapshots */
- diff.tv_sec = s->completion_time; /* completion time of the latest snapshot */
- diff.tv_usec = 0;
- tv_add(&diff, &tmp, &next_snapshot_time);
- ret = (tv_diff(&now, &next_snapshot_time, &diff) < 0)? 0 : 1;
+ ret = now;
+ if (num_complete_snapshots == 0)
+ goto out;
+ x /= num_complete_snapshots; /* avg time to create one snapshot */
+ if (unit_interval < x * wanted) /* oops, no sleep at all */
+ goto out;
+ ret = s->completion_time + unit_interval / wanted - x;
out:
free_snapshot_list(&sl);
- if (ret == 0)
- DSS_DEBUG_LOG("next snapshot due in %lu seconds\n",
- tv2ms(&diff) / 1000);
- else
- DSS_DEBUG_LOG("next snapshot: now\n");
return ret;
}
+static inline void invalidate_next_snapshot_time(void)
+{
+ next_snapshot_time = 0;
+}
+
+static inline int next_snapshot_time_is_valid(void)
+{
+ return next_snapshot_time != 0;
+}
+
+static int next_snapshot_is_due(void)
+{
+ int64_t now = get_current_time();
+
+ assert(snapshot_creation_status == HS_READY);
+ if (!next_snapshot_time_is_valid())
+ next_snapshot_time = compute_next_snapshot_time();
+ if (next_snapshot_time <= now) {
+ DSS_DEBUG_LOG("next snapshot: now\n");
+ return 1;
+ }
+ DSS_DEBUG_LOG("next snapshot due in %" PRId64 " seconds\n",
+ next_snapshot_time - now);
+ return 0;
+}
+
static int pre_create_hook(void)
{
int ret, fds[3] = {0, 0, 0};
assert(snapshot_creation_status == HS_READY);
+ /* make sure that the next snapshot time will be recomputed */
+ invalidate_next_snapshot_time();
if (!conf.pre_create_hook_given) {
snapshot_creation_status = HS_PRE_SUCCESS;
return 0;
return ret;
}
-static int pre_remove_hook(struct snapshot *s, char *why)
+static int pre_remove_hook(struct snapshot *s, const char *why)
{
int ret, fds[3] = {0, 0, 0};
char *cmd;
+ if (!s)
+ return 0;
DSS_DEBUG_LOG("%s snapshot %s\n", why, s->name);
assert(snapshot_removal_status == HS_READY);
assert(remove_pid == 0);
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 orphaned 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;
if (snapshot_is_being_created(s))
continue;
+ if (is_reference_snapshot(s))
+ continue;
//DSS_DEBUG_LOG("checking %s\n", s->name);
if (s->interval > interval) {
prev = s;
prev = s;
}
assert(victim);
- if (conf.dry_run_given) {
- dss_msg("%s would be removed (interval = %i)\n",
- victim->name, victim->interval);
- continue;
- }
- ret = pre_remove_hook(victim, "redundant");
- 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",
+ DSS_DEBUG_LOG("looking for snapshots belonging to intervals >= %d\n",
conf.num_intervals_arg);
FOR_EACH_SNAPSHOT(s, i, sl) {
if (snapshot_is_being_created(s))
continue;
- if (s->interval <= conf.num_intervals_arg)
+ if (is_reference_snapshot(s))
continue;
- if (conf.dry_run_given) {
- dss_msg("%s would be removed (interval = %i)\n",
- s->name, s->interval);
+ if (s->interval < conf.num_intervals_arg)
continue;
- }
- ret = pre_remove_hook(s, "outdated");
- if (ret < 0)
- return ret;
- return 1;
+ return s;
}
- return 0;
+ return NULL;
}
-static int remove_oldest_snapshot(struct snapshot_list *sl)
+struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
{
- int ret;
- struct snapshot *s = get_oldest_snapshot(sl);
-
- if (!s) /* no snapshot found */
- return 0;
- DSS_INFO_LOG("oldest snapshot: %s\n", s->name);
- if (snapshot_is_being_created(s))
- return 0;
- ret = pre_remove_hook(s, "oldest");
- if (ret < 0)
- return ret;
- return 1;
+ int i;
+ struct snapshot *s;
+ FOR_EACH_SNAPSHOT(s, i, sl) {
+ if (snapshot_is_being_created(s))
+ continue;
+ if (is_reference_snapshot(s))
+ continue;
+ DSS_INFO_LOG("oldest removable snapshot: %s\n", s->name);
+ return s;
+ }
+ return NULL;
}
static int rename_incomplete_snapshot(int64_t start)
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;
+ ret = disk_space_low();
+ 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 && conf.keep_redundant_given)
- return 0;
+ if (!low_disk_space) {
+ if (conf.keep_redundant_given)
+ return 0;
+ if (snapshot_creation_status != HS_READY)
+ return 0;
+ if (next_snapshot_is_due())
+ return 0;
+ }
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 && sl.num_snapshots <= 1)
+ goto out;
+ why = "outdated";
+ victim = find_outdated_snapshot(&sl);
+ if (victim)
+ goto remove;
+ why = "redundant";
+ victim = find_redundant_snapshot(&sl);
+ if (victim)
+ goto remove;
+ /* try harder only if disk space is low */
if (!low_disk_space)
goto out;
+ why = "orphaned";
+ victim = find_orphaned_snapshot(&sl);
+ if (victim)
+ goto remove;
DSS_WARNING_LOG("disk space low and nothing obvious to remove\n");
- ret = remove_oldest_snapshot(&sl);
- if (ret)
- goto out;
- DSS_CRIT_LOG("uhuhu: not enough disk space for a single snapshot\n");
+ 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:
+ ret = pre_remove_hook(victim, why);
out:
free_snapshot_list(&sl);
return ret;
DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n",
(int)create_pid, es);
snapshot_creation_status = HS_NEEDS_RESTART;
- gettimeofday(&next_snapshot_time, NULL);
- next_snapshot_time.tv_sec += 60;
+ next_snapshot_time = get_current_time() + 60;
ret = 1;
goto out;
}
if (ret < 0)
goto out;
snapshot_creation_status = HS_SUCCESS;
+ free(name_of_reference_snapshot);
+ name_of_reference_snapshot = NULL;
out:
create_pid = 0;
create_process_stopped = 0;
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;
return 1;
}
+/*
+ * Returns < 0 on errors, 0 if no config file is given and > 0 if the config
+ * file was read successfully.
+ */
static int parse_config_file(int override)
{
- int ret;
+ int ret, config_file_exists;
char *config_file;
struct stat statbuf;
char *old_logfile_arg = NULL;
old_daemon_given = conf.daemon_given;
}
- ret = stat(config_file, &statbuf);
- if (ret && conf.config_file_given) {
+ config_file_exists = !stat(config_file, &statbuf);
+ if (!config_file_exists && conf.config_file_given) {
ret = -ERRNO_TO_DSS_ERROR(errno);
DSS_ERROR_LOG("failed to stat config file %s\n", config_file);
goto out;
}
- if (!ret) {
+ if (config_file_exists) {
struct cmdline_parser_params params = {
.override = override,
.initialize = 0,
}
DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg);
// cmdline_parser_dump(logfile? logfile : stdout, &conf);
+ ret = config_file_exists;
out:
free(config_file);
if (ret < 0)
ret = parse_config_file(1);
if (ret < 0)
return ret;
+ invalidate_next_snapshot_time();
return change_to_dest_dir();
}
static void create_rsync_argv(char ***argv, int64_t *num)
{
- char *logname, *newest;
+ char *logname;
int i = 0, j;
struct snapshot_list sl;
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)[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 (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 (use_rsync_locally(logname))
(*argv)[i++] = dss_strdup(conf.source_dir_arg);
for (;;) {
fd_set rfds;
- int low_disk_space;
struct timeval *tvp;
if (remove_pid)
goto out;
continue;
}
- ret = disk_space_low();
- if (ret < 0)
- goto out;
- low_disk_space = ret;
- ret = try_to_free_disk_space(low_disk_space);
+ ret = try_to_free_disk_space();
if (ret < 0)
goto out;
if (snapshot_removal_status != HS_READY) {
{
int ret;
struct snapshot_list sl;
+ struct snapshot *victim;
struct disk_space ds;
+ const char *why;
ret = get_disk_space(".", &ds);
if (ret < 0)
return ret;
log_disk_space(&ds);
dss_get_snapshot_list(&sl);
- ret = remove_outdated_snapshot(&sl);
- if (ret < 0)
- goto out;
- if (ret > 0)
+ why = "outdated";
+ victim = find_outdated_snapshot(&sl);
+ if (victim)
goto rm;
- ret = remove_redundant_snapshot(&sl);
- if (ret < 0)
- goto out;
- if (ret > 0)
+ why = "redundant";
+ victim = find_redundant_snapshot(&sl);
+ if (victim)
goto rm;
ret = 0;
goto out;
rm:
+ if (conf.dry_run_given) {
+ dss_msg("%s snapshot %s (interval = %i)\n",
+ why, victim->name, victim->interval);
+ ret = 0;
+ goto out;
+ }
+ ret = pre_remove_hook(victim, why);
+ if (ret < 0)
+ goto out;
if (snapshot_removal_status == HS_PRE_RUNNING) {
ret = wait_for_remove_process();
if (ret < 0)
ret = parse_config_file(0);
if (ret < 0)
goto out;
+ if (ret == 0) { /* no config file given */
+ /*
+ * Parse the command line options again, but this time check
+ * that all required options are given.
+ */
+ params = (struct cmdline_parser_params) {
+ .override = 1,
+ .initialize = 1,
+ .check_required = 1,
+ .check_ambiguity = 1,
+ .print_errors = 1
+ };
+ cmdline_parser_ext(argc, argv, &conf, ¶ms); /* aborts on errors */
+ }
if (conf.daemon_given)
daemon_init();
ret = change_to_dest_dir();
projects / dss.git / blobdiff