Improve comment of snapshot_currently_being_removed.
[dss.git] / dss.c
diff --git a/dss.c b/dss.c
index 9417e26..c2aef36 100644 (file)
--- a/dss.c
+++ b/dss.c
@@ -1,8 +1,4 @@
-/*
- * 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>
 #include <sys/wait.h>
 #include <fnmatch.h>
 #include <limits.h>
-
+#include <fcntl.h>
+#include <lopsub.h>
+#include <sys/mman.h>
 
 #include "gcc-compat.h"
-#include "cmdline.h"
 #include "log.h"
 #include "str.h"
 #include "err.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 */
@@ -57,7 +81,7 @@ static int64_t next_snapshot_time;
 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;
@@ -75,6 +99,7 @@ static const char *hook_status_description[] = {HOOK_STATUS_ARRAY};
 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);
@@ -82,14 +107,17 @@ static int disk_space_low(struct disk_space *ds)
                        return ret;
                ds = &ds_struct;
        }
-       if (conf.min_free_mb_arg)
-               if (ds->free_mb < conf.min_free_mb_arg)
+       val = OPT_UINT32_VAL(DSS, MIN_FREE_MB);
+       if (val != 0)
+               if (ds->free_mb < val)
                        return 1;
-       if (conf.min_free_percent_arg)
-               if (ds->percent_free < conf.min_free_percent_arg)
+       val = OPT_UINT32_VAL(DSS, MIN_FREE_PERCENT);
+       if (val != 0)
+               if (ds->percent_free < val)
                        return 1;
-       if (conf.min_free_percent_inodes_arg)
-               if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg)
+       val = OPT_UINT32_VAL(DSS, MIN_FREE_PERCENT_INODES);
+       if (val != 0)
+               if (ds->percent_free_inodes < val)
                        return 1;
        return 0;
 }
@@ -97,12 +125,13 @@ static int disk_space_low(struct disk_space *ds)
 static void dump_dss_config(const char *msg)
 {
        const char dash[] = "-----------------------------";
+       char *lopsub_dump;
        int ret;
        FILE *log = logfile? logfile : stderr;
        struct disk_space ds;
        int64_t now = get_current_time();
 
-       if (conf.loglevel_arg > INFO)
+       if (OPT_UINT32_VAL(DSS, LOGLEVEL) > INFO)
                return;
 
        fprintf(log, "%s <%s config> %s\n", dash, msg, dash);
@@ -118,12 +147,18 @@ static void dump_dss_config(const char *msg)
 
        /* we continue on errors from get_disk_space */
 
-       fprintf(log, "\n*** command line and config file options ***\n\n");
-       cmdline_parser_dump(log, &conf);
+       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"
-               "logile: %s\n"
+               "logfile: %s\n"
                "snapshot_currently_being_removed: %s\n"
                "path_to_last_complete_snapshot: %s\n"
                "reference_snapshot: %s\n"
@@ -132,7 +167,7 @@ static void dump_dss_config(const char *msg)
                "num_consecutive_rsync_errors: %d\n"
                ,
                (int) getpid(),
-               logfile? conf.logfile_arg : "stderr",
+               logfile? OPT_STRING_VAL(RUN, LOGFILE) : "stderr",
                snapshot_currently_being_removed?
                        snapshot_currently_being_removed->name : "(none)",
                path_to_last_complete_snapshot?
@@ -172,28 +207,6 @@ static void dump_dss_config(const char *msg)
        fprintf(log, "%s </%s config> %s\n", dash, msg, dash);
 }
 
-/* a litte cpp magic helps to DRY */
-#define COMMANDS \
-       COMMAND(ls) \
-       COMMAND(create) \
-       COMMAND(prune) \
-       COMMAND(run) \
-       COMMAND(kill) \
-       COMMAND(reload) \
-
-#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)
-{
-       COMMANDS
-       DSS_EMERG_LOG(("BUG: did not find command handler\n"));
-       return -E_BUG;
-}
-#undef COMMAND
-#undef COMMANDS
-
 static int loglevel = -1;
 static const char *location_file = NULL;
 static int         location_line = -1;
@@ -222,20 +235,24 @@ __printf_1_2 void dss_log(const char* fmt,...)
        struct tm *tm;
        time_t t1;
        char str[255] = "";
+       int lpr_ll = lpr? OPT_UINT32_VAL(DSS, LOGLEVEL) : WARNING;
 
-       if (loglevel < 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: ", loglevel);
+       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);
+               fprintf(outfd, "%s:%d: ", location_file, location_line);
 #else
-       fprintf(outfd, "%s: ", location_func);
+               fprintf(outfd, "%s: ", location_func);
 #endif
        va_start(argp, fmt);
        vfprintf(outfd, fmt, argp);
@@ -247,7 +264,7 @@ __printf_1_2 void dss_log(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);
@@ -258,53 +275,148 @@ static char *get_config_file_name(void)
 {
        char *home, *config_file;
 
-       if (conf.config_file_given)
-               return dss_strdup(conf.config_file_arg);
+       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)
+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.dry_run_given) {
+       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);
-       return 1;
+       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;
+               }
+               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)
 {
-       return send_signal(SIGTERM);
-}
+       bool w_given = OPT_GIVEN(KILL, WAIT);
+       const char *arg = OPT_STRING_VAL(KILL, SIGNAL);
+       int ret, i;
 
-static int com_reload(void)
-{
-       return send_signal(SIGHUP);
+       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 int64_t compute_next_snapshot_time(void)
 {
        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),
+               = 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;
@@ -316,6 +428,7 @@ static int64_t compute_next_snapshot_time(void)
                        continue;
                num_complete++;
                x += s->completion_time - s->creation_time;
+               last_completion_time = s->completion_time;
        }
        assert(x >= 0);
 
@@ -325,7 +438,7 @@ static int64_t compute_next_snapshot_time(void)
        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;
@@ -361,8 +474,8 @@ 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", conf.pre_create_hook_arg));
-       dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg);
+       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;
 }
 
@@ -381,8 +494,8 @@ static void pre_remove_hook(struct snapshot *s, const char *why)
        *snapshot_currently_being_removed = *s;
        snapshot_currently_being_removed->name = dss_strdup(s->name);
 
-       cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
-               conf.dest_dir_arg, 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);
@@ -425,7 +538,7 @@ static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl)
        struct snapshot *s;
        int i;
 
-       DSS_DEBUG_LOG(("looking for orphaned snapshots\n"));
+       DSS_DEBUG_LOG(("looking for old incomplete snapshots\n"));
        FOR_EACH_SNAPSHOT(s, i, sl) {
                if (snapshot_is_being_created(s))
                        continue;
@@ -469,10 +582,11 @@ static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
        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);
+       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;
@@ -522,13 +636,13 @@ static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl)
        struct snapshot *s;
 
        DSS_DEBUG_LOG(("looking for snapshots belonging to intervals >= %d\n",
-               conf.num_intervals_arg));
+               OPT_UINT32_VAL(DSS, NUM_INTERVALS)));
        FOR_EACH_SNAPSHOT(s, i, sl) {
                if (snapshot_is_being_created(s))
                        continue;
                if (is_reference_snapshot(s))
                        continue;
-               if (s->interval < conf.num_intervals_arg)
+               if (s->interval < OPT_UINT32_VAL(DSS, NUM_INTERVALS))
                        continue;
                return s;
        }
@@ -541,7 +655,7 @@ static struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
        struct snapshot *s, *ref = NULL;
 
        num_complete = num_complete_snapshots(sl);
-       if (num_complete <= conf.min_complete_arg)
+       if (num_complete <= OPT_UINT32_VAL(DSS, MIN_COMPLETE))
                return NULL;
        FOR_EACH_SNAPSHOT(s, i, sl) {
                if (snapshot_is_being_created(s))
@@ -601,7 +715,7 @@ static int try_to_free_disk_space(void)
        if (tv_diff(&next_removal_check, &now, NULL) > 0)
                return 0;
        if (!low_disk_space) {
-               if (conf.keep_redundant_given)
+               if (OPT_GIVEN(DSS, KEEP_REDUNDANT))
                        return 0;
                if (snapshot_creation_status != HS_READY)
                        return 0;
@@ -619,7 +733,8 @@ static int try_to_free_disk_space(void)
         * snapshots than configured, plus one. This way there is always one
         * snapshot that can be recycled.
         */
-       if (!low_disk_space && sl.num_snapshots <= 1 << conf.num_intervals_arg)
+       if (!low_disk_space && sl.num_snapshots <=
+                       1 << OPT_UINT32_VAL(DSS, NUM_INTERVALS))
                goto out;
        why = "outdated";
        victim = find_outdated_snapshot(&sl);
@@ -637,6 +752,7 @@ static int try_to_free_disk_space(void)
        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;
@@ -652,8 +768,9 @@ out:
 
 static void post_create_hook(void)
 {
-       char *cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
-               conf.dest_dir_arg, path_to_last_complete_snapshot);
+       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);
@@ -667,8 +784,8 @@ static void post_remove_hook(void)
 
        assert(s);
 
-       cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
-               conf.dest_dir_arg, s->name);
+       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);
@@ -864,11 +981,12 @@ static int handle_rsync_exit(int status)
        if (es != 0 && es != 24) {
                DSS_WARNING_LOG(("rsync exit code %d, error count %d\n",
                        es, ++num_consecutive_rsync_errors));
-               if (conf.create_given) {
+               if (!logfile) { /* called by com_run() */
                        ret = -E_BAD_EXIT_CODE;
                        goto out;
                }
-               if (num_consecutive_rsync_errors > conf.max_rsync_errors_arg) {
+               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;
@@ -905,7 +1023,7 @@ static int handle_pre_create_hook_exit(int status)
        if (es) {
                if (!warn_count--) {
                        DSS_NOTICE_LOG(("pre_create_hook %s returned %d\n",
-                               conf.pre_create_hook_arg, es));
+                               OPT_STRING_VAL(DSS, PRE_CREATE_HOOK), es));
                        DSS_NOTICE_LOG(("deferring snapshot creation...\n"));
                        warn_count = 60; /* warn only once per hour */
                }
@@ -959,85 +1077,179 @@ static int handle_sigchld(void)
        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 || conf.num_intervals_arg > 30) {
-               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;
 }
 
-/*
- * 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(bool sighup)
+static int lopsub_error(int lopsub_ret, char **errctx)
+{
+       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, config_file_exists;
+       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 (sighup) {
-               if (conf.logfile_given)
-                       old_logfile_arg = dss_strdup(conf.logfile_arg);
-               old_daemon_given = conf.daemon_given;
+       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;
        }
-
-       config_file_exists = !stat(config_file, &statbuf);
-       if (!config_file_exists && conf.config_file_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 out;
+               goto close_fd;
        }
-       if (config_file_exists) {
-               struct cmdline_parser_params params;
-               params.override = sighup;
-               params.initialize = 0;
-               params.check_required = 1;
-               params.check_ambiguity = 0;
-               params.print_errors = 1;
-               if (sighup) { /* invalidate all rsync options */
-                       int i;
-
-                       for (i = 0; i < conf.rsync_option_given; i++) {
-                               free(conf.rsync_option_arg[i]);
-                               conf.rsync_option_arg[i] = NULL;
-                       }
-                       conf.rsync_option_given = 0;
-               }
-               cmdline_parser_config_file(config_file, &conf, &params);
+       sz = statbuf.st_size;
+       if (sz == 0) { /* config file is empty -- nothing to do */
+               ret = 0;
+               goto success;
        }
-       ret = check_config();
-       if (ret < 0)
-               goto out;
-       if (sighup) {
-               /* 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;
-               }
+       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 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 (conf.logfile_given && conf.run_given && conf.daemon_given) {
-               logfile = open_log(conf.logfile_arg);
-               log_welcome(conf.loglevel_arg);
+       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;
        }
-       DSS_DEBUG_LOG(("loglevel: %d\n", conf.loglevel_arg));
-       ret = config_file_exists;
+       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;
+       }
+       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;
+       }
+close_fd:
+       if (fd >= 0)
+               close(fd);
 out:
        free(config_file);
        if (ret < 0)
@@ -1045,24 +1257,31 @@ out:
        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, re-reading config\n"));
        dump_dss_config("old");
-       ret = parse_config_file(true /* SIGHUP */);
+       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;
+       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 change_to_dest_dir();
+       return 1;
 }
 
 static void kill_children(void)
@@ -1082,9 +1301,7 @@ static int handle_signal(void)
        switch (sig) {
        case SIGINT:
        case SIGTERM:
-               kill_children();
-               ret = -E_SIGNAL;
-               break;
+               return -E_SIGNAL;
        case SIGHUP:
                ret = handle_sighup();
                break;
@@ -1104,11 +1321,12 @@ out:
  */
 static int use_rsync_locally(char *logname)
 {
-       char *h = conf.remote_host_arg;
+       const char *h = OPT_STRING_VAL(DSS, REMOTE_HOST);
 
        if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1"))
                return 0;
-       if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname))
+       if (OPT_GIVEN(DSS, REMOTE_USER) &&
+                       strcmp(OPT_STRING_VAL(DSS, REMOTE_USER), logname))
                return 0;
        return 1;
 }
@@ -1168,20 +1386,30 @@ out:
 static void create_rsync_argv(char ***argv, int64_t *num)
 {
        char *logname;
-       int i = 0, j;
+       int i = 0, j, N = OPT_GIVEN(DSS, RSYNC_OPTION);
        struct snapshot_list sl;
+       static bool seeded;
 
        dss_get_snapshot_list(&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("-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 (!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",
@@ -1190,11 +1418,13 @@ static void create_rsync_argv(char ***argv, int64_t *num)
                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);
+               (*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);
@@ -1218,6 +1448,7 @@ static int create_snapshot(char **argv)
 {
        int ret;
 
+       assert(argv);
        ret = rename_resume_snap(current_snapshot_creation_time);
        if (ret < 0)
                return ret;
@@ -1311,15 +1542,18 @@ out:
 
 static void exit_hook(int exit_code)
 {
-       char *argv[3];
        pid_t pid;
-
-       argv[0] = conf.exit_hook_arg;
-       argv[1] = dss_strerror(-exit_code);
-       argv[2] = NULL;
-
-       DSS_NOTICE_LOG(("executing %s %s\n", argv[0], argv[1]));
-       dss_exec(&pid, conf.exit_hook_arg, argv);
+       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);
 }
 
 static void lock_dss_or_die(void)
@@ -1336,23 +1570,51 @@ static void lock_dss_or_die(void)
 
 static int com_run(void)
 {
-       int ret;
+       int ret, fd = -1;
+       char *config_file;
+       pid_t pid;
 
-       lock_dss_or_die();
-       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;
+       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)
 {
@@ -1379,7 +1641,7 @@ static int com_prune(void)
        ret = 0;
        goto out;
 rm:
-       if (conf.dry_run_given) {
+       if (OPT_GIVEN(DSS, DRY_RUN)) {
                dss_msg("%s snapshot %s (interval = %i)\n",
                        why, victim->name, victim->interval);
                ret = 0;
@@ -1412,6 +1674,7 @@ out:
        free_snapshot_list(&sl);
        return ret;
 }
+EXPORT_CMD_HANDLER(prune);
 
 static int com_create(void)
 {
@@ -1419,7 +1682,7 @@ static int com_create(void)
        char **rsync_argv;
 
        lock_dss_or_die();
-       if (conf.dry_run_given) {
+       if (OPT_GIVEN(DSS, DRY_RUN)) {
                int i;
                char *msg = NULL;
                create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
@@ -1460,23 +1723,36 @@ 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)
 {
@@ -1493,47 +1769,94 @@ static int setup_signal_handling(void)
        return install_sighandler(SIGCHLD);
 }
 
+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;
+       char *errctx = NULL;
+       unsigned num_inputs;
+       const struct dss_user_data *ud;
 
-       params.override = 0;
-       params.initialize = 1;
-       params.check_required = 0;
-       params.check_ambiguity = 0;
-       params.print_errors = 1;
-
-       cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
-       ret = parse_config_file(0);
-       ret = parse_config_file(false /* no SIGHUP */);
+       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 (ret == 0) { /* no config file given */
-               /*
-                * Parse the command line options again, but this time check
-                * that all required options are given.
-                */
-               params.override = 1;
-               params.initialize = 1;
-               params.check_required = 1;
-               params.check_ambiguity = 1;
-               params.print_errors = 1;
-               cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
+       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;
        }
-       if (conf.daemon_given)
-               daemon_init();
-       ret = change_to_dest_dir();
+       sublpr = cmdline_sublpr;
+       ret = parse_config_file(false /* no SIGHUP */, subcmd);
+       if (ret < 0)
+               goto out;
+       ret = check_config();
        if (ret < 0)
                goto out;
-       dump_dss_config("startup");
        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)
+       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);
 }