-/*
- * Copyright (C) 2008-2011 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* SPDX-License-Identifier: GPL-2.0 */
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
static bool daemonized;
/** Non-NULL if we log to a file. */
static FILE *logfile;
+/* Realpath of the config file. */
+static char *config_file;
+/* derived from config file path */
+uint32_t ipc_key;
/** The read end of the signal pipe */
static int signal_pipe;
/** Process id of current pre-create-hook/rsync/post-create-hook process. */
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. */
+/* 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;
fprintf(log, "\n*** internal state ***\n\n");
fprintf(log,
"pid: %d\n"
- "logile: %s\n"
+ "logfile: %s\n"
"snapshot_currently_being_removed: %s\n"
"path_to_last_complete_snapshot: %s\n"
"reference_snapshot: %s\n"
va_end(argp);
}
-static char *get_config_file_name(void)
+static void set_config_file_name(void)
{
- 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;
+ if (OPT_GIVEN(DSS, CONFIG_FILE)) {
+ const char *arg = OPT_STRING_VAL(DSS, CONFIG_FILE);
+ config_file = realpath(arg, NULL);
+ if (!config_file) {
+ DSS_EMERG_LOG(("could not resolve path %s: %s\n", arg,
+ strerror(errno)));
+ exit(EXIT_FAILURE);
+ }
+ } else {
+ char *home = get_homedir();
+ char *arg = make_message("%s/.dssrc", home);
+ free(home);
+ config_file = realpath(arg, NULL);
+ if (config_file)
+ free(arg);
+ else /* not fatal */
+ config_file = arg;
+ }
+ DSS_DEBUG_LOG(("config file: %s\n", config_file));
+ ipc_key = super_fast_hash((uint8_t *)config_file,
+ strlen(config_file), 0) >> 1;
}
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);
+ int ret = get_dss_pid(ipc_key, &pid);
unsigned ms = 32;
struct timespec ts;
- free(config_file);
if (ret < 0)
return ret;
if (OPT_GIVEN(DSS, DRY_RUN)) {
static int64_t compute_next_snapshot_time(void)
{
int64_t x = 0, now = get_current_time(), unit_interval
- = 24 * 3600 * OPT_UINT32_VAL(DSS, UNIT_INTERVAL), ret;
+ = 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;
continue;
num_complete++;
x += s->completion_time - s->creation_time;
+ last_completion_time = s->completion_time;
}
assert(x >= 0);
x /= num_complete; /* 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;
+ ret = last_completion_time + unit_interval / wanted - x;
out:
free_snapshot_list(&sl);
return ret;
return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
}
-/*
- * return: 0: no redundant snapshots, 1: rm process started, negative: error
- */
static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
{
int i, interval;
int i, num_complete;
struct snapshot *s, *ref = NULL;
+ DSS_DEBUG_LOG(("picking snapshot with earliest creation time\n"));
num_complete = num_complete_snapshots(sl);
if (num_complete <= OPT_UINT32_VAL(DSS, MIN_COMPLETE))
return NULL;
ref = s;
continue;
}
- DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name));
return s;
}
assert(ref);
return ref;
}
+/* returns NULL <==> *reason is set to NULL */
+static struct snapshot *find_removable_snapshot(struct snapshot_list *sl,
+ bool try_hard, char **reason)
+{
+ struct snapshot *victim;
+
+ /*
+ * 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 (!try_hard && sl->num_snapshots <=
+ 1 << OPT_UINT32_VAL(DSS, NUM_INTERVALS))
+ goto nope;
+ victim = find_orphaned_snapshot(sl);
+ if (victim) {
+ *reason = make_message("orphaned");
+ return victim;
+ }
+ victim = find_outdated_snapshot(sl);
+ if (victim) {
+ *reason = make_message("outdated");
+ return victim;
+ }
+ if (!OPT_GIVEN(DSS, KEEP_REDUNDANT)) {
+ victim = find_redundant_snapshot(sl);
+ if (victim) {
+ *reason = make_message("redundant");
+ return victim;
+ }
+ }
+ if (!try_hard)
+ goto nope;
+ DSS_WARNING_LOG(("nothing obvious to remove\n"));
+ victim = find_oldest_removable_snapshot(sl);
+ if (victim) {
+ *reason = make_message("oldest");
+ return victim;
+ }
+nope:
+ *reason = NULL;
+ return NULL;
+}
+
static int rename_incomplete_snapshot(int64_t start)
{
char *old_name;
struct snapshot_list sl;
struct snapshot *victim;
struct timeval now;
- const char *why;
+ char *why;
int low_disk_space;
ret = disk_space_low(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.
- */
+ /* Idle or low disk space, look at existing snapshots. */
dss_get_snapshot_list(&sl);
- ret = 0;
- /*
- * 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;
- 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);
+ victim = find_removable_snapshot(&sl, low_disk_space, &why);
+ if (victim) {
+ pre_remove_hook(victim, why);
+ free(why);
+ }
+ free_snapshot_list(&sl);
if (victim)
- goto remove;
- /* try harder only if disk space is low */
+ return 1;
if (!low_disk_space)
- goto out;
- DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n"));
- why = "oldest";
- victim = find_oldest_removable_snapshot(&sl);
- if (victim)
- goto remove;
+ return 0;
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;
+ return -ERRNO_TO_DSS_ERROR(ENOSPC);
}
static void post_create_hook(void)
static int check_config(void)
{
- int ret;
uint32_t unit_interval = OPT_UINT32_VAL(DSS, UNIT_INTERVAL);
uint32_t num_intervals = OPT_UINT32_VAL(DSS, NUM_INTERVALS);
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(bool sighup, const struct lls_command *cmd)
{
int ret, fd = -1;
- char *config_file = get_config_file_name();
struct stat statbuf;
void *map;
size_t sz;
if (fd >= 0)
close(fd);
out:
- free(config_file);
- if (ret < 0)
- DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
return ret;
}
switch (sig) {
case SIGINT:
case SIGTERM:
- kill_children();
- ret = -E_SIGNAL;
- break;
+ return -E_SIGNAL;
case SIGHUP:
ret = handle_sighup();
break;
static void create_rsync_argv(char ***argv, int64_t *num)
{
char *logname;
- int i = 0, j, N = OPT_GIVEN(DSS, RSYNC_OPTION);
+ int i = 0, j, N;
struct snapshot_list sl;
static bool seeded;
name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
free_snapshot_list(&sl);
- *argv = dss_malloc((15 + N) * sizeof(char *));
+ /*
+ * We specify up to 6 arguments, one argument per given rsync option
+ * and one argument per given source dir. We also need space for the
+ * terminating NULL pointer.
+ */
+ N = OPT_GIVEN(DSS, RSYNC_OPTION) + OPT_GIVEN(DSS, SOURCE_DIR);
+ *argv = dss_malloc((7 + N) * sizeof(char *));
(*argv)[i++] = dss_strdup("rsync");
(*argv)[i++] = dss_strdup("-a");
(*argv)[i++] = dss_strdup("--delete");
DSS_NOTICE_LOG(("adding --checksum to rsync options\n"));
(*argv)[i++] = dss_strdup("--checksum");
}
- for (j = 0; j < N; j++)
+ for (j = 0; j < OPT_GIVEN(DSS, RSYNC_OPTION); j++)
(*argv)[i++] = dss_strdup(lls_string_val(j,
OPT_RESULT(DSS, RSYNC_OPTION)));
if (name_of_reference_snapshot) {
} else
DSS_INFO_LOG(("no suitable reference snapshot found\n"));
logname = dss_logname();
- if (use_rsync_locally(logname))
- (*argv)[i++] = dss_strdup(OPT_STRING_VAL(DSS, SOURCE_DIR));
- else
- (*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));
+ if (use_rsync_locally(logname)) {
+ for (j = 0; j < OPT_GIVEN(DSS, SOURCE_DIR); j++)
+ (*argv)[i++] = dss_strdup(lls_string_val(j,
+ OPT_RESULT(DSS, SOURCE_DIR)));
+ } else {
+ /*
+ * dss-1.0 and earlier did not support multiple source
+ * directories. These versions appended a slash to the end of
+ * the source directory to make sure that only the contents of
+ * the single source directory, but not the directory itself,
+ * are copied to the destination. For multiple source
+ * directories, however, this is not a good idea because the
+ * source directories may well contain identical file names,
+ * which would then be copied to the same location on the
+ * destination, overwriting each other. Moreover, we want the
+ * directory on the destination match the source. To preserve
+ * the old behaviour, we thus have to special-case N=1.
+ */
+ for (j = 0; j < OPT_GIVEN(DSS, SOURCE_DIR); j++) {
+ (*argv)[i++] = make_message("%s@%s:%s%s",
+ OPT_GIVEN(DSS, REMOTE_USER)?
+ OPT_STRING_VAL(DSS, REMOTE_USER) : logname,
+ OPT_STRING_VAL(DSS, REMOTE_HOST),
+ lls_string_val(j, OPT_RESULT(DSS, SOURCE_DIR)),
+ OPT_GIVEN(DSS, SOURCE_DIR) == 1? "/" : ""
+ );
+ }
+ }
free(logname);
*num = get_current_time();
(*argv)[i++] = incomplete_name(*num);
{
int ret;
+ assert(argv);
ret = rename_resume_snap(current_snapshot_creation_time);
if (ret < 0)
return ret;
{
pid_t pid;
char **argv, *tmp = dss_strdup(OPT_STRING_VAL(DSS, EXIT_HOOK));
- unsigned n = split_args(tmp, &argv, " \t");
+ unsigned n = split_args(tmp, &argv);
n++;
argv = dss_realloc(argv, (n + 1) * sizeof(char *));
static void lock_dss_or_die(void)
{
- char *config_file = get_config_file_name();
- int ret = lock_dss(config_file);
+ int ret = lock_dss(ipc_key);
- 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, fd = -1;
- char *config_file;
pid_t pid;
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);
+ ret = get_dss_pid(ipc_key, &pid);
if (ret >= 0) {
DSS_ERROR_LOG(("pid %d\n", (int)pid));
return -E_ALREADY_RUNNING;
}
+ /*
+ * Order is important here: Since daemon_init() forks, it would drop
+ * the lock if it had been acquired already. Changing the cwd before
+ * grabbing the lock causes stat(2) to fail in case a relative config
+ * file path was given, which results in a different key ID for
+ * locking. Therefore we must first daemonize, then lock, then change
+ * the cwd.
+ */
if (OPT_GIVEN(RUN, DAEMON)) {
fd = daemon_init();
daemonized = true;
logfile = open_log(OPT_STRING_VAL(RUN, LOGFILE));
}
lock_dss_or_die();
+ ret = change_to_dest_dir();
+ if (ret < 0)
+ return ret;
dump_dss_config("startup");
ret = install_sighandler(SIGHUP);
if (ret < 0)
struct snapshot_list sl;
struct snapshot *victim;
struct disk_space ds;
- const char *why;
+ char *why;
+ bool try_hard;
lock_dss_or_die();
- ret = get_disk_space(".", &ds);
+ ret = change_to_dest_dir();
if (ret < 0)
return ret;
- log_disk_space(&ds);
+ switch (OPT_UINT32_VAL(PRUNE, DISK_SPACE)) {
+ case FDS_LOW: try_hard = true; break;
+ case FDS_HIGH: try_hard = false; break;
+ default:
+ ret = get_disk_space(".", &ds);
+ if (ret < 0)
+ return ret;
+ log_disk_space(&ds);
+ try_hard = disk_space_low(&ds);
+ }
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:
+ victim = find_removable_snapshot(&sl, try_hard, &why);
+ if (!victim) {
+ dss_msg("nothing to prune\n");
+ ret = 0;
+ goto free_sl;
+ }
if (OPT_GIVEN(DSS, DRY_RUN)) {
- dss_msg("%s snapshot %s (interval = %i)\n",
+ dss_msg("picking %s snapshot %s (interval = %i)\n",
why, victim->name, victim->interval);
ret = 0;
- goto out;
+ goto free_why;
}
pre_remove_hook(victim, why);
if (snapshot_removal_status == HS_PRE_RUNNING) {
ret = wait_for_remove_process();
if (ret < 0)
- goto out;
+ goto free_why;
+ ret = -E_HOOK_FAILED;
if (snapshot_removal_status != HS_PRE_SUCCESS)
- goto out;
+ goto free_why;
}
ret = exec_rm();
if (ret < 0)
- goto out;
+ goto free_why;
ret = wait_for_remove_process();
if (ret < 0)
- goto out;
- if (snapshot_removal_status != HS_SUCCESS)
- goto out;
+ goto free_why;
+ assert(snapshot_removal_status == HS_SUCCESS);
post_remove_hook();
- if (snapshot_removal_status != HS_POST_RUNNING)
- goto out;
+ assert(snapshot_removal_status == HS_POST_RUNNING);
ret = wait_for_remove_process();
- if (ret < 0)
- goto out;
- ret = 1;
-out:
+free_why:
+ free(why);
+free_sl:
free_snapshot_list(&sl);
return ret;
}
char **rsync_argv;
lock_dss_or_die();
+ ret = change_to_dest_dir();
+ if (ret < 0)
+ return ret;
if (OPT_GIVEN(DSS, DRY_RUN)) {
int i;
char *msg = NULL;
static int com_ls(void)
{
- int i;
+ int i, ret;
struct snapshot_list sl;
struct snapshot *s;
int64_t now = get_current_time();
+ ret = change_to_dest_dir();
+ if (ret < 0)
+ return ret;
dss_get_snapshot_list(&sl);
FOR_EACH_SNAPSHOT(s, i, &sl) {
int64_t d;
return install_sighandler(SIGCHLD);
}
+const char *dss_version(void);
static void handle_version_and_help(void)
{
char *txt;
+ if (OPT_GIVEN(DSS, VERSION)) {
+ printf("%s\n", dss_version());
+ exit(EXIT_SUCCESS);
+ }
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 = dss_strdup(VERSION_STRING);
else
return;
printf("%s", txt);
+ printf("\nRun dss help for help on subcommands.\n");
free(txt);
exit(EXIT_SUCCESS);
}
const char *purpose = lls_purpose(cmd);
printf("%-11s%s\n", name, purpose);
}
- exit(EXIT_SUCCESS);
+ printf("\nRun dss help <subcmd> for help on <subcmd>.\n");
}
+static int com_help(void)
+{
+ int ret;
+ char *errctx, *help;
+ const char *arg;
+ const struct lls_command *cmd;
+
+ ret = lls_check_arg_count(sublpr, 0, 1, &errctx);
+ if (ret < 0)
+ return lopsub_error(ret, &errctx);
+ if (lls_num_inputs(sublpr) == 0) {
+ show_subcommand_summary();
+ return 0;
+ }
+ arg = lls_input(0, sublpr);
+ ret = lls_lookup_subcmd(arg, dss_suite, &errctx);
+ if (ret < 0)
+ return lopsub_error(ret, &errctx);
+ cmd = lls_cmd(ret, dss_suite);
+ if (OPT_GIVEN(HELP, LONG))
+ help = lls_long_help(cmd);
+ else
+ help = lls_short_help(cmd);
+ printf("%s", help);
+ free(help);
+ if (!OPT_GIVEN(HELP, LONG))
+ printf("\nRun dss -- help -l %s for long help.\n", arg);
+ return 0;
+}
+EXPORT_CMD_HANDLER(help);
+
int main(int argc, char **argv)
{
int ret;
goto out;
}
lpr = cmdline_lpr;
+ set_config_file_name();
ret = parse_config_file(false /* no SIGHUP */, CMD_PTR(DSS));
if (ret < 0)
goto out;
handle_version_and_help();
num_inputs = lls_num_inputs(lpr);
- if (num_inputs == 0)
+ if (num_inputs == 0) {
show_subcommand_summary();
+ ret = 0;
+ goto out;
+ }
ret = lls_lookup_subcmd(argv[argc - num_inputs], dss_suite, &errctx);
if (ret < 0) {
ret = lopsub_error(ret, &errctx);
lls_free_parse_result(sublpr, subcmd);
if (sublpr != cmdline_sublpr)
lls_free_parse_result(cmdline_sublpr, subcmd);
+ free(config_file);
exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
}