static pid_t remove_pid;
/** When the next snapshot is due. */
static struct timeval 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. */
+struct snapshot *snapshot_currently_being_removed;
/** Needed by the post-create hook. */
static char *path_to_last_complete_snapshot;
/** \sa \ref snap.h for details. */
get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
}
-static void compute_next_snapshot_time(void)
+static int next_snapshot_is_due(void)
{
struct timeval now, unit_interval = {.tv_sec = 24 * 3600 * conf.unit_interval_arg},
tmp, diff;
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);
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 */
- goto min_sleep;
+ if (ret < 0 || !s) { /* unit_interval < tmp or no snapshot */
+ ret = 1;
+ goto out;
+ }
+
tv_divide(wanted, &diff, &tmp); /* sleep time betweeen two snapshots */
diff.tv_sec = s->completion_time; /* completion time of the the latest snaphot */
diff.tv_usec = 0;
tv_add(&diff, &tmp, &next_snapshot_time);
- gettimeofday(&now, NULL);
- if (tv_diff(&now, &next_snapshot_time, NULL) < 0)
- goto out;
-min_sleep:
- next_snapshot_time = now;
- next_snapshot_time.tv_sec += 60;
+ ret = (tv_diff(&now, &next_snapshot_time, &diff) < 0)? 0 : 1;
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 int pre_create_hook(void)
+{
+ int ret, fds[3] = {0, 0, 0};
+
+ assert(snapshot_creation_status == HS_READY);
+ if (!conf.pre_create_hook_given) {
+ snapshot_creation_status = HS_PRE_SUCCESS;
+ return 0;
+ }
+ 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 = HS_PRE_RUNNING;
+ return ret;
+}
-static int remove_snapshot(struct snapshot *s, char *why)
+static int pre_remove_hook(struct snapshot *s, char *why)
{
+ int ret, fds[3] = {0, 0, 0};
+ char *cmd;
+
+ 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);
+
+ if (!conf.pre_remove_hook_given) {
+ snapshot_removal_status = HS_PRE_SUCCESS;
+ return 0;
+ }
+ cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
+ conf.dest_dir_arg, s->name);
+ DSS_DEBUG_LOG("executing %s\n", cmd);
+ ret = dss_exec_cmdline_pid(&remove_pid,
+ conf.pre_remove_hook_arg, fds);
+ free(cmd);
+ if (ret < 0)
+ return ret;
+ snapshot_removal_status = HS_PRE_RUNNING;
+ return ret;
+}
+
+static int exec_rm(void)
+{
+ struct snapshot *s = snapshot_currently_being_removed;
int fds[3] = {0, 0, 0};
- 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};
+ int ret;
+
+ 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 snapshot %s (interval = %i)\n",
- why, s->name, s->interval);
ret = dss_exec(&remove_pid, argv[0], argv, fds);
+ if (ret < 0)
+ goto out;
+ snapshot_removal_status = HS_RUNNING;
out:
free(new_name);
return ret;
victim->name, victim->interval);
continue;
}
- ret = remove_snapshot(victim, "redundant");
+ ret = pre_remove_hook(victim, "redundant");
return ret < 0? ret : 1;
}
return 0;
s->name, s->interval);
continue;
}
- ret = remove_snapshot(s, "outdated");
+ ret = pre_remove_hook(s, "outdated");
if (ret < 0)
return ret;
return 1;
DSS_INFO_LOG("oldest snapshot: %s\n", s->name);
if (snapshot_is_being_created(s))
return 0;
- return remove_snapshot(s, "oldest");
+ return pre_remove_hook(s, "oldest");
}
static int rename_incomplete_snapshot(int64_t start)
{
int ret;
struct snapshot_list sl;
+ struct timeval now;
+ gettimeofday(&now, NULL);
+ if (tv_diff(&next_removal_check, &now, NULL) > 0)
+ return 0;
if (!low_disk_space && conf.keep_redundant_given)
return 0;
dss_get_snapshot_list(&sl);
return ret;
}
-static int pre_create_hook(void)
+static int post_create_hook(void)
{
int ret, fds[3] = {0, 0, 0};
+ char *cmd;
- if (!conf.pre_create_hook_given) {
- snapshot_creation_status = HS_PRE_SUCCESS;
+ if (!conf.post_create_hook_given) {
+ snapshot_creation_status = HS_READY;
return 0;
}
- DSS_DEBUG_LOG("executing %s\n", conf.pre_create_hook_arg);
- ret = dss_exec_cmdline_pid(&create_pid,
- conf.pre_create_hook_arg, fds);
+ cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
+ conf.dest_dir_arg, path_to_last_complete_snapshot);
+ DSS_NOTICE_LOG("executing %s\n", cmd);
+ ret = dss_exec_cmdline_pid(&create_pid, cmd, fds);
+ free(cmd);
if (ret < 0)
return ret;
- snapshot_creation_status = HS_PRE_RUNNING;
+ snapshot_creation_status = HS_POST_RUNNING;
return ret;
}
-static int post_create_hook(void)
+static int 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 = HS_READY;
- compute_next_snapshot_time();
+ assert(s);
+
+ if (!conf.post_remove_hook_given) {
+ snapshot_removal_status = HS_READY;
return 0;
}
- cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
- conf.dest_dir_arg, path_to_last_complete_snapshot);
+ cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
+ conf.dest_dir_arg, s->name);
DSS_NOTICE_LOG("executing %s\n", cmd);
- ret = dss_exec_cmdline_pid(&create_pid, cmd, fds);
+ ret = dss_exec_cmdline_pid(&remove_pid, cmd, fds);
free(cmd);
if (ret < 0)
return ret;
- snapshot_creation_status = HS_POST_RUNNING;
+ snapshot_removal_status = HS_POST_RUNNING;
return ret;
}
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)
{
- remove_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(remove_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)
DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)create_pid);
ret = -E_INVOLUNTARY_EXIT;
snapshot_creation_status = HS_READY;
- compute_next_snapshot_time();
goto out;
}
es = WEXITSTATUS(status);
DSS_ERROR_LOG("rsync process %d returned %d\n", (int)create_pid, es);
ret = -E_BAD_EXIT_CODE;
snapshot_creation_status = HS_READY;
- compute_next_snapshot_time();
goto out;
}
ret = rename_incomplete_snapshot(current_snapshot_creation_time);
if (!WIFEXITED(status)) {
snapshot_creation_status = HS_READY;
- compute_next_snapshot_time();
ret = -E_INVOLUNTARY_EXIT;
goto out;
}
warn_count = 60; /* warn only once per hour */
}
snapshot_creation_status = HS_READY;
- compute_next_snapshot_time();
ret = 0;
goto out;
}
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",
return -E_BUG;
}
}
- if (pid == remove_pid)
- return handle_rm_exit(status);
+ 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;
}
for (;;) {
fd_set rfds;
int low_disk_space;
- struct timeval now, *tvp;
+ struct timeval *tvp;
if (remove_pid)
- tvp = NULL; /* sleep until rm process dies */
+ tvp = NULL; /* sleep until rm hook/process dies */
else { /* sleep one minute */
tv.tv_sec = 60;
tv.tv_usec = 0;
}
if (remove_pid)
continue;
+ if (snapshot_removal_status == HS_PRE_SUCCESS) {
+ ret = exec_rm();
+ if (ret < 0)
+ goto out;
+ continue;
+ }
+ if (snapshot_removal_status == HS_SUCCESS) {
+ ret = post_remove_hook();
+ if (ret < 0)
+ goto out;
+ continue;
+ }
ret = disk_space_low();
if (ret < 0)
goto out;
ret = try_to_free_disk_space(low_disk_space);
if (ret < 0)
goto out;
- if (remove_pid) {
+ if (snapshot_removal_status != HS_READY) {
stop_create_process();
continue;
}
restart_create_process();
- gettimeofday(&now, NULL);
- if (tv_diff(&next_snapshot_time, &now, NULL) > 0)
- continue;
switch (snapshot_creation_status) {
case HS_READY:
+ if (!next_snapshot_is_due())
+ continue;
ret = pre_create_hook();
if (ret < 0)
goto out;
continue;
case HS_PRE_RUNNING:
- continue;
- case HS_NEEDS_RESTART:
- ret = create_snapshot(rsync_argv);
- if (ret < 0)
- goto out;
+ case HS_RUNNING:
+ case HS_POST_RUNNING:
continue;
case HS_PRE_SUCCESS:
free_rsync_argv(rsync_argv);
create_rsync_argv(&rsync_argv, ¤t_snapshot_creation_time);
+ /* fall through */
+ case HS_NEEDS_RESTART:
ret = create_snapshot(rsync_argv);
if (ret < 0)
goto out;
continue;
- case HS_RUNNING:
- continue;
case HS_SUCCESS:
ret = post_create_hook();
if (ret < 0)
goto out;
continue;
- case HS_POST_RUNNING:
- continue;
}
}
out:
ret = install_sighandler(SIGHUP);
if (ret < 0)
return ret;
- compute_next_snapshot_time();
ret = select_loop();
if (ret >= 0) /* impossible */
ret = -E_BUG;
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();
+ dss_get_snapshot_list(&sl);
+ ret = remove_outdated_snapshot(&sl);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ goto rm;
+ ret = remove_redundant_snapshot(&sl);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ goto rm;
+ ret = 0;
+ goto out;
+rm:
+ if (snapshot_removal_status == HS_PRE_RUNNING) {
+ ret = wait_for_remove_process();
if (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();
- if (ret < 0)
+ 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;
+ ret = post_remove_hook();
+ if (ret < 0)
+ goto out;
+ 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;
}
projects / dss.git / commitdiff