dss.c

   1 /*
   2  * Copyright (C) 2008-2011 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6 #include <string.h>
   7 #include <stdlib.h>
   8 #include <stdarg.h>
   9 #include <assert.h>
  10 #include <errno.h>
  11 #include <sys/types.h>
  12 #include <signal.h>
  13 #include <ctype.h>
  14 #include <sys/stat.h>
  15 #include <unistd.h>
  16 #include <inttypes.h>
  17 #include <sys/time.h>
  18 #include <time.h>
  19 #include <sys/wait.h>
  20 #include <fnmatch.h>
  21 #include <limits.h>
  22
  23
  24 #include "gcc-compat.h"
  25 #include "cmdline.h"
  26 #include "log.h"
  27 #include "string.h"
  28 #include "error.h"
  29 #include "fd.h"
  30 #include "exec.h"
  31 #include "daemon.h"
  32 #include "signal.h"
  33 #include "df.h"
  34 #include "time.h"
  35 #include "snap.h"
  36
  37 /** Command line and config file options. */
  38 static struct gengetopt_args_info conf;
  39 /** Non-NULL if we log to a file. */
  40 static FILE *logfile;
  41 /** The read end of the signal pipe */
  42 static int signal_pipe;
  43 /** Process id of current pre-create-hook/rsync/post-create-hook process. */
  44 static pid_t create_pid;
  45 /** Whether the pre-create-hook/rsync/post-create-hook is currently stopped. */
  46 static int create_process_stopped;
  47 /** Process id of current pre-remove/rm/post-remove process. */
  48 static pid_t remove_pid;
  49 /** When the next snapshot is due. */
  50 static int64_t next_snapshot_time;
  51 /** When to try to remove something. */
  52 static struct timeval next_removal_check;
  53 /** Creation time of the snapshot currently being created. */
  54 static int64_t current_snapshot_creation_time;
  55 /** The snapshot currently being removed. */
  56 struct snapshot *snapshot_currently_being_removed;
  57 /** Needed by the post-create hook. */
  58 static char *path_to_last_complete_snapshot;
  59 static char *name_of_reference_snapshot;
  60 /** \sa \ref snap.h for details. */
  61 enum hook_status snapshot_creation_status;
  62 /** \sa \ref snap.h for details. */
  63 enum hook_status snapshot_removal_status;
  64
  65
  66 DEFINE_DSS_ERRLIST;
  67 static const char *hook_status_description[] = {HOOK_STATUS_ARRAY};
  68
  69 /* may be called with ds == NULL. */
  70 static int disk_space_low(struct disk_space *ds)
  71 {
  72         struct disk_space ds_struct;
  73
  74         if (!ds) {
  75                 int ret = get_disk_space(".", &ds_struct);
  76                 if (ret < 0)
  77                         return ret;
  78                 ds = &ds_struct;
  79         }
  80         if (conf.min_free_mb_arg)
  81                 if (ds->free_mb < conf.min_free_mb_arg)
  82                         return 1;
  83         if (conf.min_free_percent_arg)
  84                 if (ds->percent_free < conf.min_free_percent_arg)
  85                         return 1;
  86         if (conf.min_free_percent_inodes_arg)
  87                 if (ds->percent_free_inodes < conf.min_free_percent_inodes_arg)
  88                         return 1;
  89         return 0;
  90 }
  91
  92 static void dump_dss_config(const char *msg)
  93 {
  94         const char dash[] = "-----------------------------";
  95         int ret;
  96         FILE *log = logfile? logfile : stderr;
  97         struct disk_space ds;
  98         int64_t now = get_current_time();
  99
 100         if (conf.loglevel_arg > INFO)
 101                 return;
 102
 103         fprintf(log, "%s <%s config> %s\n", dash, msg, dash);
 104         fprintf(log, "\n*** disk space ***\n\n");
 105         ret = get_disk_space(".", &ds);
 106         if (ret >= 0) {
 107                 DSS_INFO_LOG("disk space low: %s\n", disk_space_low(&ds)?
 108                         "yes" : "no");
 109                 log_disk_space(&ds);
 110         } else
 111                 DSS_ERROR_LOG("can not get free disk space: %s\n",
 112                         dss_strerror(-ret));
 113
 114         /* we continue on errors from get_disk_space */
 115
 116         fprintf(log, "\n*** command line and config file options ***\n\n");
 117         cmdline_parser_dump(log, &conf);
 118         fprintf(log, "\n*** internal state ***\n\n");
 119         fprintf(log,
 120                 "pid: %d\n"
 121                 "logile: %s\n"
 122                 "snapshot_currently_being_removed: %s\n"
 123                 "path_to_last_complete_snapshot: %s\n"
 124                 "reference_snapshot: %s\n"
 125                 "snapshot_creation_status: %s\n"
 126                 "snapshot_removal_status: %s\n"
 127                 ,
 128                 (int) getpid(),
 129                 logfile? conf.logfile_arg : "stderr",
 130                 snapshot_currently_being_removed?
 131                         snapshot_currently_being_removed->name : "(none)",
 132                 path_to_last_complete_snapshot?
 133                         path_to_last_complete_snapshot : "(none)",
 134                 name_of_reference_snapshot?
 135                         name_of_reference_snapshot : "(none)",
 136                 hook_status_description[snapshot_creation_status],
 137                 hook_status_description[snapshot_removal_status]
 138         );
 139         if (create_pid != 0)
 140                 fprintf(log,
 141                         "create_pid: %" PRId32 "\n"
 142                         "create process is %sstopped\n"
 143                         ,
 144                         create_pid,
 145                         create_process_stopped? "" : "not "
 146                 );
 147         if (remove_pid != 0)
 148                 fprintf(log, "remove_pid: %" PRId32 "\n", remove_pid);
 149         if (next_snapshot_time != 0)
 150                 fprintf(log, "next snapshot due in %" PRId64 " seconds\n",
 151                         next_snapshot_time - now);
 152         if (current_snapshot_creation_time != 0)
 153                 fprintf(log, "current_snapshot_creation_time: %"
 154                         PRId64 " (%" PRId64 " seconds ago)\n",
 155                         current_snapshot_creation_time,
 156                         now - current_snapshot_creation_time
 157                 );
 158         if (next_removal_check.tv_sec != 0) {
 159                 fprintf(log, "next removal check: %llu (%llu seconds ago)\n",
 160                         (long long unsigned)next_removal_check.tv_sec,
 161                         now - (long long unsigned)next_removal_check.tv_sec
 162                 );
 163
 164         }
 165         fprintf(log, "%s </%s config> %s\n", dash, msg, dash);
 166 }
 167
 168 /* a litte cpp magic helps to DRY */
 169 #define COMMANDS \
 170         COMMAND(ls) \
 171         COMMAND(create) \
 172         COMMAND(prune) \
 173         COMMAND(run)
 174 #define COMMAND(x) static int com_ ##x(void);
 175 COMMANDS
 176 #undef COMMAND
 177 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
 178 static int call_command_handler(void)
 179 {
 180         COMMANDS
 181         DSS_EMERG_LOG("BUG: did not find command handler\n");
 182         return -E_BUG;
 183 }
 184 #undef COMMAND
 185 #undef COMMANDS
 186
 187 /**
 188  * The log function of dss.
 189  *
 190  * \param ll Loglevel.
 191  * \param fml Usual format string.
 192  *
 193  * All DSS_XXX_LOG() macros use this function.
 194  */
 195 __printf_2_3 void dss_log(int ll, const char* fmt,...)
 196 {
 197         va_list argp;
 198         FILE *outfd;
 199         struct tm *tm;
 200         time_t t1;
 201         char str[255] = "";
 202
 203         if (ll < conf.loglevel_arg)
 204                 return;
 205         outfd = logfile? logfile : stderr;
 206         time(&t1);
 207         tm = localtime(&t1);
 208         strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
 209         fprintf(outfd, "%s ", str);
 210         if (conf.loglevel_arg <= INFO)
 211                 fprintf(outfd, "%i: ", ll);
 212         va_start(argp, fmt);
 213         vfprintf(outfd, fmt, argp);
 214         va_end(argp);
 215 }
 216
 217 /**
 218  * Print a message either to stdout or to the log file.
 219  */
 220 static __printf_1_2 void dss_msg(const char* fmt,...)
 221 {
 222         FILE *outfd = conf.daemon_given? logfile : stdout;
 223         va_list argp;
 224         va_start(argp, fmt);
 225         vfprintf(outfd, fmt, argp);
 226         va_end(argp);
 227 }
 228
 229 static void dss_get_snapshot_list(struct snapshot_list *sl)
 230 {
 231         get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
 232 }
 233
 234 static int64_t compute_next_snapshot_time(void)
 235 {
 236         int64_t x = 0, now = get_current_time(), unit_interval
 237                 = 24 * 3600 * conf.unit_interval_arg, ret;
 238         unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
 239                 num_complete_snapshots = 0;
 240         int i;
 241         struct snapshot *s = NULL;
 242         struct snapshot_list sl;
 243
 244         dss_get_snapshot_list(&sl);
 245         FOR_EACH_SNAPSHOT(s, i, &sl) {
 246                 if (!(s->flags & SS_COMPLETE))
 247                         continue;
 248                 num_complete_snapshots++;
 249                 x += s->completion_time - s->creation_time;
 250         }
 251         assert(x >= 0);
 252
 253         ret = now;
 254         if (num_complete_snapshots == 0)
 255                 goto out;
 256         x /= num_complete_snapshots; /* avg time to create one snapshot */
 257         if (unit_interval < x * wanted) /* oops, no sleep at all */
 258                 goto out;
 259         ret = s->completion_time + unit_interval / wanted - x;
 260 out:
 261         free_snapshot_list(&sl);
 262         return ret;
 263 }
 264
 265 static inline void invalidate_next_snapshot_time(void)
 266 {
 267         next_snapshot_time = 0;
 268 }
 269
 270 static inline int next_snapshot_time_is_valid(void)
 271 {
 272         return next_snapshot_time != 0;
 273 }
 274
 275 static int next_snapshot_is_due(void)
 276 {
 277         int64_t now = get_current_time();
 278
 279         if (!next_snapshot_time_is_valid())
 280                 next_snapshot_time = compute_next_snapshot_time();
 281         if (next_snapshot_time <= now) {
 282                 DSS_DEBUG_LOG("next snapshot: now\n");
 283                 return 1;
 284         }
 285         DSS_DEBUG_LOG("next snapshot due in %" PRId64 " seconds\n",
 286                 next_snapshot_time - now);
 287         return 0;
 288 }
 289
 290 static void pre_create_hook(void)
 291 {
 292         assert(snapshot_creation_status == HS_READY);
 293         /* make sure that the next snapshot time will be recomputed */
 294         invalidate_next_snapshot_time();
 295         DSS_DEBUG_LOG("executing %s\n", conf.pre_create_hook_arg);
 296         dss_exec_cmdline_pid(&create_pid, conf.pre_create_hook_arg);
 297         snapshot_creation_status = HS_PRE_RUNNING;
 298 }
 299
 300 static void pre_remove_hook(struct snapshot *s, const char *why)
 301 {
 302         char *cmd;
 303
 304         if (!s)
 305                 return;
 306         DSS_DEBUG_LOG("%s snapshot %s\n", why, s->name);
 307         assert(snapshot_removal_status == HS_READY);
 308         assert(remove_pid == 0);
 309         assert(!snapshot_currently_being_removed);
 310
 311         snapshot_currently_being_removed = dss_malloc(sizeof(struct snapshot));
 312         *snapshot_currently_being_removed = *s;
 313         snapshot_currently_being_removed->name = dss_strdup(s->name);
 314
 315         cmd = make_message("%s %s/%s", conf.pre_remove_hook_arg,
 316                 conf.dest_dir_arg, s->name);
 317         DSS_DEBUG_LOG("executing %s\n", cmd);
 318         dss_exec_cmdline_pid(&remove_pid, cmd);
 319         free(cmd);
 320         snapshot_removal_status = HS_PRE_RUNNING;
 321 }
 322
 323 static int exec_rm(void)
 324 {
 325         struct snapshot *s = snapshot_currently_being_removed;
 326         char *new_name = being_deleted_name(s);
 327         char *argv[4];
 328         int ret;
 329
 330         argv[0] = "rm";
 331         argv[1] = "-rf";
 332         argv[2] = new_name;
 333         argv[3] = NULL;
 334
 335         assert(snapshot_removal_status == HS_PRE_SUCCESS);
 336         assert(remove_pid == 0);
 337
 338         DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval);
 339         ret = dss_rename(s->name, new_name);
 340         if (ret < 0)
 341                 goto out;
 342         dss_exec(&remove_pid, argv[0], argv);
 343         snapshot_removal_status = HS_RUNNING;
 344 out:
 345         free(new_name);
 346         return ret;
 347 }
 348
 349 static int snapshot_is_being_created(struct snapshot *s)
 350 {
 351         return s->creation_time == current_snapshot_creation_time;
 352 }
 353
 354 static struct snapshot *find_orphaned_snapshot(struct snapshot_list *sl)
 355 {
 356         struct snapshot *s;
 357         int i;
 358
 359         DSS_DEBUG_LOG("looking for orphaned snapshots\n");
 360         FOR_EACH_SNAPSHOT(s, i, sl) {
 361                 if (snapshot_is_being_created(s))
 362                         continue;
 363                 /*
 364                  * We know that no rm is currently running, so if s is marked
 365                  * as being deleted, a previously started rm must have failed.
 366                  */
 367                 if (s->flags & SS_BEING_DELETED)
 368                         return s;
 369
 370                 if (s->flags & SS_COMPLETE) /* good snapshot */
 371                         continue;
 372                 /*
 373                  * This snapshot is incomplete and it is not the snapshot
 374                  * currently being created. However, we must not remove it if
 375                  * rsync is about to be restarted. As only the newest snapshot
 376                  * can be restarted, this snapshot is orphaned if it is not the
 377                  * newest snapshot or if we are not about to restart rsync.
 378                  */
 379                 if (get_newest_snapshot(sl) != s)
 380                         return s;
 381                 if (snapshot_creation_status != HS_NEEDS_RESTART)
 382                         return s;
 383         }
 384         /* no orphaned snapshots */
 385         return NULL;
 386 }
 387
 388 static int is_reference_snapshot(struct snapshot *s)
 389 {
 390         if (!name_of_reference_snapshot)
 391                 return 0;
 392         return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
 393 }
 394
 395 /*
 396  * return: 0: no redundant snapshots, 1: rm process started, negative: error
 397  */
 398 static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
 399 {
 400         int i, interval;
 401         struct snapshot *s;
 402         unsigned missing = 0;
 403
 404         DSS_DEBUG_LOG("looking for intervals containing too many snapshots\n");
 405         for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
 406                 unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg);
 407                 unsigned num = sl->interval_count[interval];
 408                 struct snapshot *victim = NULL, *prev = NULL;
 409                 int64_t score = LONG_MAX;
 410
 411                 if (keep >= num)
 412                         missing += keep - num;
 413                 if (keep + missing >= num)
 414                         continue;
 415                 /* redundant snapshot in this interval, pick snapshot with lowest score */
 416                 FOR_EACH_SNAPSHOT(s, i, sl) {
 417                         int64_t this_score;
 418
 419                         if (snapshot_is_being_created(s))
 420                                 continue;
 421                         if (is_reference_snapshot(s))
 422                                 continue;
 423                         if (s->interval > interval) {
 424                                 prev = s;
 425                                 continue;
 426                         }
 427                         if (s->interval < interval)
 428                                 break;
 429                         if (!victim) {
 430                                 victim = s;
 431                                 prev = s;
 432                                 continue;
 433                         }
 434                         assert(prev);
 435                         /* check if s is a better victim */
 436                         this_score = s->creation_time - prev->creation_time;
 437                         assert(this_score >= 0);
 438                         if (this_score < score) {
 439                                 score = this_score;
 440                                 victim = s;
 441                         }
 442                         prev = s;
 443                 }
 444                 assert(victim);
 445                 return victim;
 446         }
 447         return NULL;
 448 }
 449
 450 static struct snapshot *find_outdated_snapshot(struct snapshot_list *sl)
 451 {
 452         int i;
 453         struct snapshot *s;
 454
 455         DSS_DEBUG_LOG("looking for snapshots belonging to intervals >= %d\n",
 456                 conf.num_intervals_arg);
 457         FOR_EACH_SNAPSHOT(s, i, sl) {
 458                 if (snapshot_is_being_created(s))
 459                         continue;
 460                 if (is_reference_snapshot(s))
 461                         continue;
 462                 if (s->interval < conf.num_intervals_arg)
 463                         continue;
 464                 return s;
 465         }
 466         return NULL;
 467 }
 468
 469 struct snapshot *find_oldest_removable_snapshot(struct snapshot_list *sl)
 470 {
 471         int i;
 472         struct snapshot *s;
 473         FOR_EACH_SNAPSHOT(s, i, sl) {
 474                 if (snapshot_is_being_created(s))
 475                         continue;
 476                 if (is_reference_snapshot(s))
 477                         continue;
 478                 DSS_INFO_LOG("oldest removable snapshot: %s\n", s->name);
 479                 return s;
 480         }
 481         return NULL;
 482 }
 483
 484 static int rename_incomplete_snapshot(int64_t start)
 485 {
 486         char *old_name;
 487         int ret;
 488
 489         free(path_to_last_complete_snapshot);
 490         ret = complete_name(start, get_current_time(),
 491                 &path_to_last_complete_snapshot);
 492         if (ret < 0)
 493                 return ret;
 494         old_name = incomplete_name(start);
 495         ret = dss_rename(old_name, path_to_last_complete_snapshot);
 496         if (ret >= 0)
 497                 DSS_NOTICE_LOG("%s -> %s\n", old_name,
 498                         path_to_last_complete_snapshot);
 499         free(old_name);
 500         return ret;
 501 }
 502
 503 static int try_to_free_disk_space(void)
 504 {
 505         int ret;
 506         struct snapshot_list sl;
 507         struct snapshot *victim;
 508         struct timeval now;
 509         const char *why;
 510         int low_disk_space;
 511
 512         ret = disk_space_low(NULL);
 513         if (ret < 0)
 514                 return ret;
 515         low_disk_space = ret;
 516         gettimeofday(&now, NULL);
 517         if (tv_diff(&next_removal_check, &now, NULL) > 0)
 518                 return 0;
 519         if (!low_disk_space) {
 520                 if (conf.keep_redundant_given)
 521                         return 0;
 522                 if (snapshot_creation_status != HS_READY)
 523                         return 0;
 524                 if (next_snapshot_is_due())
 525                         return 0;
 526         }
 527         dss_get_snapshot_list(&sl);
 528         ret = 0;
 529         if (!low_disk_space && sl.num_snapshots <= 1)
 530                 goto out;
 531         why = "outdated";
 532         victim = find_outdated_snapshot(&sl);
 533         if (victim)
 534                 goto remove;
 535         why = "redundant";
 536         victim = find_redundant_snapshot(&sl);
 537         if (victim)
 538                 goto remove;
 539         /* try harder only if disk space is low */
 540         if (!low_disk_space)
 541                 goto out;
 542         why = "orphaned";
 543         victim = find_orphaned_snapshot(&sl);
 544         if (victim)
 545                 goto remove;
 546         DSS_WARNING_LOG("disk space low and nothing obvious to remove\n");
 547         victim = find_oldest_removable_snapshot(&sl);
 548         if (victim)
 549                 goto remove;
 550         DSS_CRIT_LOG("uhuhu: disk space low and nothing to remove\n");
 551         ret = -ERRNO_TO_DSS_ERROR(ENOSPC);
 552         goto out;
 553 remove:
 554         pre_remove_hook(victim, why);
 555 out:
 556         free_snapshot_list(&sl);
 557         return ret;
 558 }
 559
 560 static void post_create_hook(void)
 561 {
 562         char *cmd = make_message("%s %s/%s", conf.post_create_hook_arg,
 563                 conf.dest_dir_arg, path_to_last_complete_snapshot);
 564         DSS_NOTICE_LOG("executing %s\n", cmd);
 565         dss_exec_cmdline_pid(&create_pid, cmd);
 566         free(cmd);
 567         snapshot_creation_status = HS_POST_RUNNING;
 568 }
 569
 570 static void post_remove_hook(void)
 571 {
 572         char *cmd;
 573         struct snapshot *s = snapshot_currently_being_removed;
 574
 575         assert(s);
 576
 577         cmd = make_message("%s %s/%s", conf.post_remove_hook_arg,
 578                 conf.dest_dir_arg, s->name);
 579         DSS_NOTICE_LOG("executing %s\n", cmd);
 580         dss_exec_cmdline_pid(&remove_pid, cmd);
 581         free(cmd);
 582         snapshot_removal_status = HS_POST_RUNNING;
 583 }
 584
 585 static void dss_kill(pid_t pid, int sig, const char *msg)
 586 {
 587         const char *signame, *process_name;
 588
 589         if (pid == 0)
 590                 return;
 591         switch (sig) {
 592         case SIGTERM: signame = "TERM"; break;
 593         case SIGSTOP: signame = "STOP"; break;
 594         case SIGCONT: signame = "CONT"; break;
 595         default: signame = "????";
 596         }
 597
 598         if (pid == create_pid)
 599                 process_name = "create";
 600         else if (pid == remove_pid)
 601                 process_name = "remove";
 602         else process_name = "??????";
 603
 604         if (msg)
 605                 DSS_INFO_LOG("%s\n", msg);
 606         DSS_DEBUG_LOG("sending signal %d (%s) to pid %d (%s process)\n",
 607                 sig, signame, (int)pid, process_name);
 608         if (kill(pid, sig) >= 0)
 609                 return;
 610         DSS_INFO_LOG("failed to send signal %d (%s) to pid %d (%s process)\n",
 611                 sig, signame, (int)pid, process_name);
 612 }
 613
 614 static void stop_create_process(void)
 615 {
 616         if (create_process_stopped)
 617                 return;
 618         dss_kill(create_pid, SIGSTOP, "suspending create process");
 619         create_process_stopped = 1;
 620 }
 621
 622 static void restart_create_process(void)
 623 {
 624         if (!create_process_stopped)
 625                 return;
 626         dss_kill(create_pid, SIGCONT, "resuming create process");
 627         create_process_stopped = 0;
 628 }
 629
 630 /**
 631  * Print a log message about the exit status of a child.
 632  */
 633 static void log_termination_msg(pid_t pid, int status)
 634 {
 635         if (WIFEXITED(status))
 636                 DSS_INFO_LOG("child %i exited. Exit status: %i\n", (int)pid,
 637                         WEXITSTATUS(status));
 638         else if (WIFSIGNALED(status))
 639                 DSS_NOTICE_LOG("child %i was killed by signal %i\n", (int)pid,
 640                         WTERMSIG(status));
 641         else
 642                 DSS_WARNING_LOG("child %i terminated abormally\n", (int)pid);
 643 }
 644
 645 static int wait_for_process(pid_t pid, int *status)
 646 {
 647         int ret;
 648
 649         DSS_DEBUG_LOG("Waiting for process %d to terminate\n", (int)pid);
 650         for (;;) {
 651                 fd_set rfds;
 652
 653                 FD_ZERO(&rfds);
 654                 FD_SET(signal_pipe, &rfds);
 655                 ret = dss_select(signal_pipe + 1, &rfds, NULL, NULL);
 656                 if (ret < 0)
 657                         break;
 658                 ret = next_signal();
 659                 if (!ret)
 660                         continue;
 661                 if (ret == SIGCHLD) {
 662                         ret = waitpid(pid, status, 0);
 663                         if (ret >= 0)
 664                                 break;
 665                         if (errno != EINTR) { /* error */
 666                                 ret = -ERRNO_TO_DSS_ERROR(errno);
 667                                 break;
 668                         }
 669                 }
 670                 /* SIGINT or SIGTERM */
 671                 dss_kill(pid, SIGTERM, "killing child process");
 672         }
 673         if (ret < 0)
 674                 DSS_ERROR_LOG("failed to wait for process %d\n", (int)pid);
 675         else
 676                 log_termination_msg(pid, *status);
 677         return ret;
 678 }
 679
 680 static void handle_pre_remove_exit(int status)
 681 {
 682         if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 683                 snapshot_removal_status = HS_READY;
 684                 gettimeofday(&next_removal_check, NULL);
 685                 next_removal_check.tv_sec += 60;
 686                 return;
 687         }
 688         snapshot_removal_status = HS_PRE_SUCCESS;
 689 }
 690
 691 static int handle_rm_exit(int status)
 692 {
 693         if (!WIFEXITED(status)) {
 694                 snapshot_removal_status = HS_READY;
 695                 return -E_INVOLUNTARY_EXIT;
 696         }
 697         if (WEXITSTATUS(status)) {
 698                 snapshot_removal_status = HS_READY;
 699                 return -E_BAD_EXIT_CODE;
 700         }
 701         snapshot_removal_status = HS_SUCCESS;
 702         return 1;
 703 }
 704
 705 static void handle_post_remove_exit(void)
 706 {
 707         snapshot_removal_status = HS_READY;
 708 }
 709
 710 static int handle_remove_exit(int status)
 711 {
 712         int ret;
 713         struct snapshot *s = snapshot_currently_being_removed;
 714
 715         assert(s);
 716         switch (snapshot_removal_status) {
 717         case HS_PRE_RUNNING:
 718                 handle_pre_remove_exit(status);
 719                 ret = 1;
 720                 break;
 721         case HS_RUNNING:
 722                 ret = handle_rm_exit(status);
 723                 break;
 724         case HS_POST_RUNNING:
 725                 handle_post_remove_exit();
 726                 ret = 1;
 727                 break;
 728         default:
 729                 ret = -E_BUG;
 730         }
 731         if (snapshot_removal_status == HS_READY) {
 732                 free(s->name);
 733                 free(s);
 734                 snapshot_currently_being_removed = NULL;
 735         }
 736         remove_pid = 0;
 737         return ret;
 738 }
 739
 740 static int wait_for_remove_process(void)
 741 {
 742         int status, ret;
 743
 744         assert(remove_pid);
 745         assert(
 746                 snapshot_removal_status == HS_PRE_RUNNING ||
 747                 snapshot_removal_status == HS_RUNNING ||
 748                 snapshot_removal_status == HS_POST_RUNNING
 749         );
 750         ret = wait_for_process(remove_pid, &status);
 751         if (ret < 0)
 752                 return ret;
 753         return handle_remove_exit(status);
 754 }
 755
 756 static int handle_rsync_exit(int status)
 757 {
 758         int es, ret;
 759
 760         if (!WIFEXITED(status)) {
 761                 DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)create_pid);
 762                 ret = -E_INVOLUNTARY_EXIT;
 763                 snapshot_creation_status = HS_READY;
 764                 goto out;
 765         }
 766         es = WEXITSTATUS(status);
 767         /*
 768          * Restart rsync on non-fatal errors:
 769          * 12: Error in rsync protocol data stream
 770          * 13: Errors with program diagnostics
 771          */
 772         if (es == 12 || es == 13) {
 773                 DSS_WARNING_LOG("rsync process %d returned %d -- restarting\n",
 774                         (int)create_pid, es);
 775                 snapshot_creation_status = HS_NEEDS_RESTART;
 776                 next_snapshot_time = get_current_time() + 60;
 777                 ret = 1;
 778                 goto out;
 779         }
 780         if (es != 0 && es != 23 && es != 24) {
 781                 DSS_ERROR_LOG("rsync process %d returned %d\n", (int)create_pid, es);
 782                 ret = -E_BAD_EXIT_CODE;
 783                 snapshot_creation_status = HS_READY;
 784                 goto out;
 785         }
 786         ret = rename_incomplete_snapshot(current_snapshot_creation_time);
 787         if (ret < 0)
 788                 goto out;
 789         snapshot_creation_status = HS_SUCCESS;
 790         free(name_of_reference_snapshot);
 791         name_of_reference_snapshot = NULL;
 792 out:
 793         create_process_stopped = 0;
 794         return ret;
 795 }
 796
 797 static int handle_pre_create_hook_exit(int status)
 798 {
 799         int es, ret;
 800         static int warn_count;
 801
 802         if (!WIFEXITED(status)) {
 803                 snapshot_creation_status = HS_READY;
 804                 ret = -E_INVOLUNTARY_EXIT;
 805                 goto out;
 806         }
 807         es = WEXITSTATUS(status);
 808         if (es) {
 809                 if (!warn_count--) {
 810                         DSS_NOTICE_LOG("pre_create_hook %s returned %d\n",
 811                                 conf.pre_create_hook_arg, es);
 812                         DSS_NOTICE_LOG("deferring snapshot creation...\n");
 813                         warn_count = 60; /* warn only once per hour */
 814                 }
 815                 next_snapshot_time = get_current_time() + 60;
 816                 snapshot_creation_status = HS_READY;
 817                 ret = 0;
 818                 goto out;
 819         }
 820         warn_count = 0;
 821         snapshot_creation_status = HS_PRE_SUCCESS;
 822         ret = 1;
 823 out:
 824         return ret;
 825 }
 826
 827 static int handle_sigchld(void)
 828 {
 829         pid_t pid;
 830         int status, ret = reap_child(&pid, &status);
 831
 832         if (ret <= 0)
 833                 return ret;
 834
 835         if (pid == create_pid) {
 836                 switch (snapshot_creation_status) {
 837                 case HS_PRE_RUNNING:
 838                         ret = handle_pre_create_hook_exit(status);
 839                         break;
 840                 case HS_RUNNING:
 841                         ret = handle_rsync_exit(status);
 842                         break;
 843                 case HS_POST_RUNNING:
 844                         snapshot_creation_status = HS_READY;
 845                         ret = 1;
 846                         break;
 847                 default:
 848                         DSS_EMERG_LOG("BUG: create can't die in status %d\n",
 849                                 snapshot_creation_status);
 850                         return -E_BUG;
 851                 }
 852                 create_pid = 0;
 853                 return ret;
 854         }
 855         if (pid == remove_pid) {
 856                 ret = handle_remove_exit(status);
 857                 if (ret < 0)
 858                         return ret;
 859                 return ret;
 860         }
 861         DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid);
 862         return -E_BUG;
 863 }
 864
 865 static int check_config(void)
 866 {
 867         if (conf.unit_interval_arg <= 0) {
 868                 DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg);
 869                 return -E_INVALID_NUMBER;
 870         }
 871         DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg);
 872         if (conf.num_intervals_arg <= 0) {
 873                 DSS_ERROR_LOG("bad number of intervals  %i\n", conf.num_intervals_arg);
 874                 return -E_INVALID_NUMBER;
 875         }
 876         DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg);
 877         return 1;
 878 }
 879
 880 /*
 881  * Returns < 0 on errors, 0 if no config file is given and > 0 if the config
 882  * file was read successfully.
 883  */
 884 static int parse_config_file(int override)
 885 {
 886         int ret, config_file_exists;
 887         char *config_file;
 888         struct stat statbuf;
 889         char *old_logfile_arg = NULL;
 890         int old_daemon_given = 0;
 891
 892         if (conf.config_file_given)
 893                 config_file = dss_strdup(conf.config_file_arg);
 894         else {
 895                 char *home = get_homedir();
 896                 config_file = make_message("%s/.dssrc", home);
 897                 free(home);
 898         }
 899         if (override) { /* SIGHUP */
 900                 if (conf.logfile_given)
 901                         old_logfile_arg = dss_strdup(conf.logfile_arg);
 902                 old_daemon_given = conf.daemon_given;
 903         }
 904
 905         config_file_exists = !stat(config_file, &statbuf);
 906         if (!config_file_exists && conf.config_file_given) {
 907                 ret = -ERRNO_TO_DSS_ERROR(errno);
 908                 DSS_ERROR_LOG("failed to stat config file %s\n", config_file);
 909                 goto out;
 910         }
 911         if (config_file_exists) {
 912                 struct cmdline_parser_params params;
 913                 params.override = override;
 914                 params.initialize = 0;
 915                 params.check_required = 1;
 916                 params.check_ambiguity = 0;
 917                 params.print_errors = 1;
 918                 if (override) { /* invalidate all rsync options */
 919                         int i;
 920
 921                         for (i = 0; i < conf.rsync_option_given; i++) {
 922                                 free(conf.rsync_option_arg[i]);
 923                                 conf.rsync_option_arg[i] = NULL;
 924                         }
 925                         conf.rsync_option_given = 0;
 926                 }
 927                 cmdline_parser_config_file(config_file, &conf, &params);
 928         }
 929         ret = check_config();
 930         if (ret < 0)
 931                 goto out;
 932         if (override) {
 933                 /* don't change daemon mode on SIGHUP */
 934                 conf.daemon_given = old_daemon_given;
 935                 close_log(logfile);
 936                 logfile = NULL;
 937                 if (conf.logfile_given)
 938                         free(old_logfile_arg);
 939                 else if (conf.daemon_given) { /* re-use old logfile */
 940                         conf.logfile_arg = old_logfile_arg;
 941                         conf.logfile_given = 1;
 942                 }
 943         }
 944         if (conf.logfile_given && conf.run_given && conf.daemon_given) {
 945                 logfile = open_log(conf.logfile_arg);
 946                 log_welcome(conf.loglevel_arg);
 947         }
 948         DSS_DEBUG_LOG("loglevel: %d\n", conf.loglevel_arg);
 949         ret = config_file_exists;
 950 out:
 951         free(config_file);
 952         if (ret < 0)
 953                 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
 954         return ret;
 955 }
 956
 957 static int change_to_dest_dir(void)
 958 {
 959         DSS_INFO_LOG("changing cwd to %s\n", conf.dest_dir_arg);
 960         return dss_chdir(conf.dest_dir_arg);
 961 }
 962
 963 static int handle_sighup(void)
 964 {
 965         int ret;
 966
 967         DSS_NOTICE_LOG("SIGHUP, re-reading config\n");
 968         dump_dss_config("old");
 969         ret = parse_config_file(1);
 970         if (ret < 0)
 971                 return ret;
 972         dump_dss_config("reloaded");
 973         invalidate_next_snapshot_time();
 974         return change_to_dest_dir();
 975 }
 976
 977 static int handle_signal(void)
 978 {
 979         int sig, ret = next_signal();
 980
 981         if (ret <= 0)
 982                 goto out;
 983         sig = ret;
 984         switch (sig) {
 985         case SIGINT:
 986         case SIGTERM:
 987                 restart_create_process();
 988                 dss_kill(create_pid, SIGTERM, NULL);
 989                 dss_kill(remove_pid, SIGTERM, NULL);
 990                 ret = -E_SIGNAL;
 991                 break;
 992         case SIGHUP:
 993                 ret = handle_sighup();
 994                 break;
 995         case SIGCHLD:
 996                 ret = handle_sigchld();
 997                 break;
 998         }
 999 out:
1000         if (ret < 0)
1001                 DSS_ERROR_LOG("%s\n", dss_strerror(-ret));
1002         return ret;
1003 }
1004
1005 /*
1006  * We can not use rsync locally if the local user is different from the remote
1007  * user or if the src dir is not on the local host (or both).
1008  */
1009 static int use_rsync_locally(char *logname)
1010 {
1011         char *h = conf.remote_host_arg;
1012
1013         if (strcmp(h, "localhost") && strcmp(h, "127.0.0.1"))
1014                 return 0;
1015         if (conf.remote_user_given && strcmp(conf.remote_user_arg, logname))
1016                 return 0;
1017         return 1;
1018 }
1019
1020 static int rename_resume_snap(int64_t creation_time)
1021 {
1022         struct snapshot_list sl;
1023         struct snapshot *s = NULL;
1024         char *new_name = incomplete_name(creation_time);
1025         int ret;
1026         const char *why;
1027
1028         sl.num_snapshots = 0;
1029
1030         ret = 0;
1031         if (conf.no_resume_given)
1032                 goto out;
1033         dss_get_snapshot_list(&sl);
1034         /*
1035          * Snapshot recycling: We first look at the newest snapshot. If this
1036          * snapshot happens to be incomplete, the last rsync process was
1037          * aborted and we reuse this one. Otherwise we look at snapshots which
1038          * could be removed (outdated and redundant snapshots) as candidates
1039          * for recycling. If no outdated/redundant snapshot exists, we check if
1040          * there is an orphaned snapshot, which likely is useless anyway.
1041          *
1042          * Only if no existing snapshot is suitable for recycling, we bite the
1043          * bullet and create a new one.
1044          */
1045         s = get_newest_snapshot(&sl);
1046         if (!s) /* no snapshots at all */
1047                 goto out;
1048         /* re-use last snapshot if it is incomplete */
1049         why = "aborted";
1050         if ((s->flags & SS_COMPLETE) == 0)
1051                 goto out;
1052         why = "outdated";
1053         s = find_outdated_snapshot(&sl);
1054         if (s)
1055                 goto out;
1056         why = "redundant";
1057         s = find_redundant_snapshot(&sl);
1058         if (s)
1059                 goto out;
1060         why = "orphaned";
1061         s = find_orphaned_snapshot(&sl);
1062 out:
1063         if (s) {
1064                 DSS_INFO_LOG("reusing %s snapshot %s\n", why, s->name);
1065                 ret = dss_rename(s->name, new_name);
1066         }
1067         if (ret >= 0)
1068                 DSS_NOTICE_LOG("creating new snapshot %s\n", new_name);
1069         free(new_name);
1070         free_snapshot_list(&sl);
1071         return ret;
1072 }
1073
1074 static void create_rsync_argv(char ***argv, int64_t *num)
1075 {
1076         char *logname;
1077         int i = 0, j;
1078         struct snapshot_list sl;
1079
1080         dss_get_snapshot_list(&sl);
1081         assert(!name_of_reference_snapshot);
1082         name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
1083         free_snapshot_list(&sl);
1084
1085         *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
1086         (*argv)[i++] = dss_strdup("rsync");
1087         (*argv)[i++] = dss_strdup("-aq");
1088         (*argv)[i++] = dss_strdup("--delete");
1089         for (j = 0; j < conf.rsync_option_given; j++)
1090                 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
1091         if (name_of_reference_snapshot) {
1092                 DSS_INFO_LOG("using %s as reference\n", name_of_reference_snapshot);
1093                 (*argv)[i++] = make_message("--link-dest=../%s",
1094                         name_of_reference_snapshot);
1095         } else
1096                 DSS_INFO_LOG("no suitable reference snapshot found\n");
1097         logname = dss_logname();
1098         if (use_rsync_locally(logname))
1099                 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
1100         else
1101                 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
1102                         conf.remote_user_arg : logname,
1103                         conf.remote_host_arg, conf.source_dir_arg);
1104         free(logname);
1105         *num = get_current_time();
1106         (*argv)[i++] = incomplete_name(*num);
1107         (*argv)[i++] = NULL;
1108         for (j = 0; j < i; j++)
1109                 DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]);
1110 }
1111
1112 static void free_rsync_argv(char **argv)
1113 {
1114         int i;
1115
1116         if (!argv)
1117                 return;
1118         for (i = 0; argv[i]; i++)
1119                 free(argv[i]);
1120         free(argv);
1121 }
1122
1123 static int create_snapshot(char **argv)
1124 {
1125         int ret;
1126
1127         ret = rename_resume_snap(current_snapshot_creation_time);
1128         if (ret < 0)
1129                 return ret;
1130         dss_exec(&create_pid, argv[0], argv);
1131         snapshot_creation_status = HS_RUNNING;
1132         return ret;
1133 }
1134
1135 static int select_loop(void)
1136 {
1137         int ret;
1138         /* check every 60 seconds for free disk space */
1139         struct timeval tv;
1140         char **rsync_argv = NULL;
1141
1142         for (;;) {
1143                 fd_set rfds;
1144                 struct timeval *tvp;
1145
1146                 if (remove_pid)
1147                         tvp = NULL; /* sleep until rm hook/process dies */
1148                 else { /* sleep one minute */
1149                         tv.tv_sec = 60;
1150                         tv.tv_usec = 0;
1151                         tvp = &tv;
1152                 }
1153                 FD_ZERO(&rfds);
1154                 FD_SET(signal_pipe, &rfds);
1155                 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
1156                 if (ret < 0)
1157                         goto out;
1158                 if (FD_ISSET(signal_pipe, &rfds)) {
1159                         ret = handle_signal();
1160                         if (ret < 0)
1161                                 goto out;
1162                 }
1163                 if (remove_pid)
1164                         continue;
1165                 if (snapshot_removal_status == HS_PRE_SUCCESS) {
1166                         ret = exec_rm();
1167                         if (ret < 0)
1168                                 goto out;
1169                         continue;
1170                 }
1171                 if (snapshot_removal_status == HS_SUCCESS) {
1172                         post_remove_hook();
1173                         continue;
1174                 }
1175                 ret = try_to_free_disk_space();
1176                 if (ret < 0)
1177                         goto out;
1178                 if (snapshot_removal_status != HS_READY) {
1179                         stop_create_process();
1180                         continue;
1181                 }
1182                 restart_create_process();
1183                 switch (snapshot_creation_status) {
1184                 case HS_READY:
1185                         if (!next_snapshot_is_due())
1186                                 continue;
1187                         pre_create_hook();
1188                         continue;
1189                 case HS_PRE_RUNNING:
1190                 case HS_RUNNING:
1191                 case HS_POST_RUNNING:
1192                         continue;
1193                 case HS_PRE_SUCCESS:
1194                         if (!name_of_reference_snapshot) {
1195                                 free_rsync_argv(rsync_argv);
1196                                 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1197                         }
1198                         ret = create_snapshot(rsync_argv);
1199                         if (ret < 0)
1200                                 goto out;
1201                         continue;
1202                 case HS_NEEDS_RESTART:
1203                         if (!next_snapshot_is_due())
1204                                 continue;
1205                         ret = create_snapshot(rsync_argv);
1206                         if (ret < 0)
1207                                 goto out;
1208                         continue;
1209                 case HS_SUCCESS:
1210                         post_create_hook();
1211                         continue;
1212                 }
1213         }
1214 out:
1215         return ret;
1216 }
1217
1218 static void exit_hook(int exit_code)
1219 {
1220         char *argv[3];
1221         pid_t pid;
1222
1223         argv[0] = conf.exit_hook_arg;
1224         argv[1] = dss_strerror(-exit_code);
1225         argv[2] = NULL;
1226
1227         DSS_NOTICE_LOG("executing %s %s\n", argv[0], argv[1]);
1228         dss_exec(&pid, conf.exit_hook_arg, argv);
1229 }
1230
1231 static int com_run(void)
1232 {
1233         int ret;
1234
1235         if (conf.dry_run_given) {
1236                 DSS_ERROR_LOG("dry_run not supported by this command\n");
1237                 return -E_SYNTAX;
1238         }
1239         ret = install_sighandler(SIGHUP);
1240         if (ret < 0)
1241                 return ret;
1242         ret = select_loop();
1243         if (ret >= 0) /* impossible */
1244                 ret = -E_BUG;
1245         exit_hook(ret);
1246         return ret;
1247 }
1248
1249 static int com_prune(void)
1250 {
1251         int ret;
1252         struct snapshot_list sl;
1253         struct snapshot *victim;
1254         struct disk_space ds;
1255         const char *why;
1256
1257         ret = get_disk_space(".", &ds);
1258         if (ret < 0)
1259                 return ret;
1260         log_disk_space(&ds);
1261         dss_get_snapshot_list(&sl);
1262         why = "outdated";
1263         victim = find_outdated_snapshot(&sl);
1264         if (victim)
1265                 goto rm;
1266         why = "redundant";
1267         victim = find_redundant_snapshot(&sl);
1268         if (victim)
1269                 goto rm;
1270         ret = 0;
1271         goto out;
1272 rm:
1273         if (conf.dry_run_given) {
1274                 dss_msg("%s snapshot %s (interval = %i)\n",
1275                         why, victim->name, victim->interval);
1276                 ret = 0;
1277                 goto out;
1278         }
1279         pre_remove_hook(victim, why);
1280         if (snapshot_removal_status == HS_PRE_RUNNING) {
1281                 ret = wait_for_remove_process();
1282                 if (ret < 0)
1283                         goto out;
1284                 if (snapshot_removal_status != HS_PRE_SUCCESS)
1285                         goto out;
1286         }
1287         ret = exec_rm();
1288         if (ret < 0)
1289                 goto out;
1290         ret = wait_for_remove_process();
1291         if (ret < 0)
1292                 goto out;
1293         if (snapshot_removal_status != HS_SUCCESS)
1294                 goto out;
1295         post_remove_hook();
1296         if (snapshot_removal_status != HS_POST_RUNNING)
1297                 goto out;
1298         ret = wait_for_remove_process();
1299         if (ret < 0)
1300                 goto out;
1301         ret = 1;
1302 out:
1303         free_snapshot_list(&sl);
1304         return ret;
1305 }
1306
1307 static int com_create(void)
1308 {
1309         int ret, status;
1310         char **rsync_argv;
1311
1312         if (conf.dry_run_given) {
1313                 int i;
1314                 char *msg = NULL;
1315                 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1316                 for (i = 0; rsync_argv[i]; i++) {
1317                         char *tmp = msg;
1318                         msg = make_message("%s%s%s", tmp? tmp : "",
1319                                 tmp? " " : "", rsync_argv[i]);
1320                         free(tmp);
1321                 }
1322                 free_rsync_argv(rsync_argv);
1323                 dss_msg("%s\n", msg);
1324                 free(msg);
1325                 return 1;
1326         }
1327         pre_create_hook();
1328         if (create_pid) {
1329                 ret = wait_for_process(create_pid, &status);
1330                 if (ret < 0)
1331                         return ret;
1332                 ret = handle_pre_create_hook_exit(status);
1333                 if (ret <= 0) /* error, or pre-create failed */
1334                         return ret;
1335         }
1336         create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
1337         ret = create_snapshot(rsync_argv);
1338         if (ret < 0)
1339                 goto out;
1340         ret = wait_for_process(create_pid, &status);
1341         if (ret < 0)
1342                 goto out;
1343         ret = handle_rsync_exit(status);
1344         if (ret < 0)
1345                 goto out;
1346         post_create_hook();
1347         if (create_pid)
1348                 ret = wait_for_process(create_pid, &status);
1349 out:
1350         free_rsync_argv(rsync_argv);
1351         return ret;
1352 }
1353
1354 static int com_ls(void)
1355 {
1356         int i;
1357         struct snapshot_list sl;
1358         struct snapshot *s;
1359
1360         dss_get_snapshot_list(&sl);
1361         FOR_EACH_SNAPSHOT(s, i, &sl) {
1362                 int64_t d = 0;
1363                 if (s->flags & SS_COMPLETE)
1364                         d = (s->completion_time - s->creation_time) / 60;
1365                 dss_msg("%u\t%s\t%3" PRId64 ":%02" PRId64 "\n", s->interval, s->name, d/60, d%60);
1366         };
1367         free_snapshot_list(&sl);
1368         return 1;
1369 }
1370
1371 static int setup_signal_handling(void)
1372 {
1373         int ret;
1374
1375         DSS_INFO_LOG("setting up signal handlers\n");
1376         signal_pipe = signal_init(); /* always successful */
1377         ret = install_sighandler(SIGINT);
1378         if (ret < 0)
1379                 return ret;
1380         ret = install_sighandler(SIGTERM);
1381         if (ret < 0)
1382                 return ret;
1383         return install_sighandler(SIGCHLD);
1384 }
1385
1386 /**
1387  * The main function of dss.
1388  *
1389  * \param argc Usual argument count.
1390  * \param argv Usual argument vector.
1391  */
1392 int main(int argc, char **argv)
1393 {
1394         int ret;
1395         struct cmdline_parser_params params;
1396
1397         params.override = 0;
1398         params.initialize = 1;
1399         params.check_required = 0;
1400         params.check_ambiguity = 0;
1401         params.print_errors = 1;
1402
1403         cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
1404         ret = parse_config_file(0);
1405         if (ret < 0)
1406                 goto out;
1407         if (ret == 0) { /* no config file given */
1408                 /*
1409                  * Parse the command line options again, but this time check
1410                  * that all required options are given.
1411                  */
1412                 struct cmdline_parser_params params;
1413                 params.override = 1;
1414                 params.initialize = 1;
1415                 params.check_required = 1;
1416                 params.check_ambiguity = 1;
1417                 params.print_errors = 1;
1418                 cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
1419         }
1420         if (conf.daemon_given)
1421                 daemon_init();
1422         ret = change_to_dest_dir();
1423         if (ret < 0)
1424                 goto out;
1425         dump_dss_config("startup");
1426         ret = setup_signal_handling();
1427         if (ret < 0)
1428                 goto out;
1429         ret = call_command_handler();
1430 out:
1431         if (ret < 0)
1432                 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
1433         exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
1434 }