dss.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdarg.h>
   4 #include <assert.h>
   5 #include <errno.h>
   6 #include <sys/types.h>
   7 #include <signal.h>
   8 #include <ctype.h>
   9 #include <sys/stat.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include <sys/time.h>
  13 #include <time.h>
  14 #include <sys/wait.h>
  15 #include <fnmatch.h>
  16 #include <limits.h>
  17
  18
  19 #include "gcc-compat.h"
  20 #include "cmdline.h"
  21 #include "log.h"
  22 #include "string.h"
  23 #include "error.h"
  24 #include "fd.h"
  25 #include "exec.h"
  26 #include "daemon.h"
  27 #include "signal.h"
  28 #include "df.h"
  29 #include "time.h"
  30 #include "snap.h"
  31
  32
  33 static struct gengetopt_args_info conf;
  34 static FILE *logfile;
  35 static int signal_pipe;
  36
  37 /** Process id of current rsync process. */
  38 static pid_t rsync_pid;
  39 /** Whether the rsync process is currently stopped */
  40 static int rsync_stopped;
  41 /** Process id of current rm process. */
  42 static pid_t rm_pid;
  43 /** When the next snapshot is due. */
  44 static struct timeval next_snapshot_time;
  45 /** The pid of the pre-create hook. */
  46 static pid_t pre_create_hook_pid;
  47 /** The pid of the post-create hook. */
  48 static pid_t post_create_hook_pid;
  49 /* Creation time of the snapshot currently being created. */
  50 static int64_t current_snapshot_creation_time;
  51
  52 static char *path_to_last_complete_snapshot;
  53
  54 static unsigned snapshot_creation_status;
  55
  56
  57 DEFINE_DSS_ERRLIST;
  58
  59
  60 /* a litte cpp magic helps to DRY */
  61 #define COMMANDS \
  62         COMMAND(ls) \
  63         COMMAND(create) \
  64         COMMAND(prune) \
  65         COMMAND(run)
  66 #define COMMAND(x) static int com_ ##x(void);
  67 COMMANDS
  68 #undef COMMAND
  69 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
  70 static int call_command_handler(void)
  71 {
  72         COMMANDS
  73         DSS_EMERG_LOG("BUG: did not find command handler\n");
  74         exit(EXIT_FAILURE);
  75 }
  76 #undef COMMAND
  77 #undef COMMANDS
  78
  79 __printf_2_3 void dss_log(int ll, const char* fmt,...)
  80 {
  81         va_list argp;
  82         FILE *outfd;
  83         struct tm *tm;
  84         time_t t1;
  85         char str[255] = "";
  86
  87         if (ll < conf.loglevel_arg)
  88                 return;
  89         outfd = logfile? logfile : stderr;
  90         time(&t1);
  91         tm = localtime(&t1);
  92         strftime(str, sizeof(str), "%b %d %H:%M:%S", tm);
  93         fprintf(outfd, "%s ", str);
  94         if (conf.loglevel_arg <= INFO)
  95                 fprintf(outfd, "%i: ", ll);
  96         va_start(argp, fmt);
  97         vfprintf(outfd, fmt, argp);
  98         va_end(argp);
  99 }
 100
 101 /**
 102  * Print a message either to stdout or to the log file.
 103  */
 104 static __printf_1_2 void dss_msg(const char* fmt,...)
 105 {
 106         FILE *outfd = conf.daemon_given? logfile : stdout;
 107         va_list argp;
 108         va_start(argp, fmt);
 109         vfprintf(outfd, fmt, argp);
 110         va_end(argp);
 111 }
 112
 113 /* TODO: Also consider number of inodes. */
 114 static int disk_space_low(void)
 115 {
 116         struct disk_space ds;
 117         int ret = get_disk_space(".", &ds);
 118
 119         if (ret < 0)
 120                 return ret;
 121         if (conf.min_free_mb_arg)
 122                 if (ds.free_mb < conf.min_free_mb_arg)
 123                         return 1;
 124         if (conf.min_free_percent_arg)
 125                 if (ds.percent_free < conf.min_free_percent_arg)
 126                         return 1;
 127         return 0;
 128 }
 129
 130 static void dss_get_snapshot_list(struct snapshot_list *sl)
 131 {
 132         get_snapshot_list(sl, conf.unit_interval_arg, conf.num_intervals_arg);
 133 }
 134
 135 static void compute_next_snapshot_time(void)
 136 {
 137         struct timeval now, unit_interval = {.tv_sec = 24 * 3600 * conf.unit_interval_arg},
 138                 tmp, diff;
 139         int64_t x = 0;
 140         unsigned wanted = desired_number_of_snapshots(0, conf.num_intervals_arg),
 141                 num_complete_snapshots = 0;
 142         int i, ret;
 143         struct snapshot *s = NULL;
 144         struct snapshot_list sl;
 145
 146         assert(snapshot_creation_status == SCS_READY);
 147         current_snapshot_creation_time = 0;
 148         dss_get_snapshot_list(&sl);
 149         FOR_EACH_SNAPSHOT(s, i, &sl) {
 150                 if (!(s->flags & SS_COMPLETE))
 151                         continue;
 152                 num_complete_snapshots++;
 153                 x += s->completion_time - s->creation_time;
 154         }
 155         assert(x >= 0);
 156         if (num_complete_snapshots)
 157                 x /= num_complete_snapshots; /* avg time to create one snapshot */
 158         x *= wanted; /* time to create all snapshots in interval 0 */
 159         tmp.tv_sec = x;
 160         tmp.tv_usec = 0;
 161         ret = tv_diff(&unit_interval, &tmp, &diff); /* total sleep time per unit interval */
 162         gettimeofday(&now, NULL);
 163         if (ret < 0 || !s)
 164                 goto min_sleep;
 165         tv_divide(wanted, &diff, &tmp); /* sleep time betweeen two snapshots */
 166         diff.tv_sec = s->completion_time;
 167         diff.tv_usec = 0;
 168         tv_add(&diff, &tmp, &next_snapshot_time);
 169         if (tv_diff(&now, &next_snapshot_time, NULL) < 0)
 170                 goto out;
 171 min_sleep:
 172         next_snapshot_time = now;
 173         next_snapshot_time.tv_sec += 60;
 174 out:
 175         free_snapshot_list(&sl);
 176 }
 177
 178
 179 static int remove_snapshot(struct snapshot *s)
 180 {
 181         int fds[3] = {0, 0, 0};
 182         assert(!rm_pid);
 183         char *new_name = being_deleted_name(s);
 184         int ret = dss_rename(s->name, new_name);
 185         char *argv[] = {"rm", "-rf", new_name, NULL};
 186
 187         if (ret < 0)
 188                 goto out;
 189         DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval);
 190         ret = dss_exec(&rm_pid, argv[0], argv, fds);
 191 out:
 192         free(new_name);
 193         return ret;
 194 }
 195
 196 /*
 197  * return: 0: no redundant snapshots, 1: rm process started, negative: error
 198  */
 199 static int remove_redundant_snapshot(struct snapshot_list *sl)
 200 {
 201         int ret, i, interval;
 202         struct snapshot *s;
 203         unsigned missing = 0;
 204
 205         DSS_INFO_LOG("looking for intervals containing too many snapshots\n");
 206         for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
 207                 unsigned keep = desired_number_of_snapshots(interval, conf.num_intervals_arg);
 208                 unsigned num = sl->interval_count[interval];
 209                 struct snapshot *victim = NULL, *prev = NULL;
 210                 int64_t score = LONG_MAX;
 211
 212                 if (keep >= num)
 213                         missing += keep - num;
 214 //              DSS_DEBUG_LOG("interval %i: keep: %u, have: %u, missing: %u\n",
 215 //                      interval, keep, num, missing);
 216                 if (keep + missing >= num)
 217                         continue;
 218                 /* redundant snapshot in this interval, pick snapshot with lowest score */
 219                 FOR_EACH_SNAPSHOT(s, i, sl) {
 220                         int64_t this_score;
 221
 222                         //DSS_DEBUG_LOG("checking %s\n", s->name);
 223                         if (s->interval > interval) {
 224                                 prev = s;
 225                                 continue;
 226                         }
 227                         if (s->interval < interval)
 228                                 break;
 229                         if (!victim) {
 230                                 victim = s;
 231                                 prev = s;
 232                                 continue;
 233                         }
 234                         assert(prev);
 235                         /* check if s is a better victim */
 236                         this_score = s->creation_time - prev->creation_time;
 237                         assert(this_score >= 0);
 238                         //DSS_DEBUG_LOG("%s: score %lli\n", s->name, (long long)score);
 239                         if (this_score < score) {
 240                                 score = this_score;
 241                                 victim = s;
 242                         }
 243                         prev = s;
 244                 }
 245                 assert(victim);
 246                 if (conf.dry_run_given) {
 247                         dss_msg("%s would be removed (interval = %i)\n",
 248                                 victim->name, victim->interval);
 249                         continue;
 250                 }
 251                 ret = remove_snapshot(victim);
 252                 return ret < 0? ret : 1;
 253         }
 254         return 0;
 255 }
 256
 257 static int remove_outdated_snapshot(struct snapshot_list *sl)
 258 {
 259         int i, ret;
 260         struct snapshot *s;
 261
 262         DSS_INFO_LOG("looking for snapshots belonging to intervals greater than %d\n",
 263                 conf.num_intervals_arg);
 264         FOR_EACH_SNAPSHOT(s, i, sl) {
 265                 if (s->interval <= conf.num_intervals_arg)
 266                         continue;
 267                 if (conf.dry_run_given) {
 268                         dss_msg("%s would be removed (interval = %i)\n",
 269                                 s->name, s->interval);
 270                         continue;
 271                 }
 272                 ret = remove_snapshot(s);
 273                 if (ret < 0)
 274                         return ret;
 275                 return 1;
 276         }
 277         return 0;
 278 }
 279
 280 static int remove_oldest_snapshot(struct snapshot_list *sl)
 281 {
 282         struct snapshot *s = get_oldest_snapshot(sl);
 283
 284         if (!s) /* no snapshot found */
 285                 return 0;
 286         DSS_INFO_LOG("oldest snapshot: %s\n", s->name);
 287         if (s->creation_time == current_snapshot_creation_time)
 288                 return 0; /* do not remove the snapshot currently being created */
 289         return remove_snapshot(s);
 290 }
 291
 292 static int rename_incomplete_snapshot(int64_t start)
 293 {
 294         char *old_name;
 295         int ret;
 296
 297         free(path_to_last_complete_snapshot);
 298         ret = complete_name(start, get_current_time(),
 299                 &path_to_last_complete_snapshot);
 300         if (ret < 0)
 301                 return ret;
 302         old_name = incomplete_name(start);
 303         ret = dss_rename(old_name, path_to_last_complete_snapshot);
 304         if (ret >= 0)
 305                 DSS_NOTICE_LOG("%s -> %s\n", old_name,
 306                         path_to_last_complete_snapshot);
 307         free(old_name);
 308         return ret;
 309 }
 310
 311 static int try_to_free_disk_space(int low_disk_space)
 312 {
 313         int ret;
 314         struct snapshot_list sl;
 315
 316         dss_get_snapshot_list(&sl);
 317         ret = remove_outdated_snapshot(&sl);
 318         if (ret) /* error, or we are removing something */
 319                 goto out;
 320         /* no outdated snapshot */
 321         ret = remove_redundant_snapshot(&sl);
 322         if (ret)
 323                 goto out;
 324         ret = 0;
 325         if (!low_disk_space)
 326                 goto out;
 327         DSS_WARNING_LOG("disk space low and nothing obvious to remove\n");
 328         ret = remove_oldest_snapshot(&sl);
 329         if (ret)
 330                 goto out;
 331         DSS_CRIT_LOG("uhuhu: not enough disk space for a single snapshot\n");
 332         ret= -ENOSPC;
 333 out:
 334         free_snapshot_list(&sl);
 335         return ret;
 336 }
 337
 338 static int pre_create_hook(void)
 339 {
 340         int ret, fds[3] = {0, 0, 0};
 341
 342         if (!conf.pre_create_hook_given) {
 343                 snapshot_creation_status = SCS_PRE_HOOK_SUCCESS;
 344                 return 0;
 345         }
 346         DSS_NOTICE_LOG("executing %s\n", conf.pre_create_hook_arg);
 347         ret = dss_exec_cmdline_pid(&pre_create_hook_pid,
 348                 conf.pre_create_hook_arg, fds);
 349         if (ret < 0)
 350                 return ret;
 351         snapshot_creation_status = SCS_PRE_HOOK_RUNNING;
 352         return ret;
 353 }
 354
 355 static int post_create_hook(void)
 356 {
 357         int ret, fds[3] = {0, 0, 0};
 358         char *cmd;
 359
 360         if (!conf.post_create_hook_given) {
 361                 snapshot_creation_status = SCS_READY;
 362                 compute_next_snapshot_time();
 363                 return 0;
 364         }
 365         cmd = make_message("%s %s", conf.post_create_hook_arg,
 366                 path_to_last_complete_snapshot);
 367         DSS_NOTICE_LOG("executing %s\n", cmd);
 368         ret = dss_exec_cmdline_pid(&post_create_hook_pid, cmd, fds);
 369         free(cmd);
 370         if (ret < 0)
 371                 return ret;
 372         snapshot_creation_status = SCS_POST_HOOK_RUNNING;
 373         return ret;
 374 }
 375
 376 static void kill_process(pid_t pid)
 377 {
 378         if (!pid)
 379                 return;
 380         DSS_WARNING_LOG("sending SIGTERM to pid %d\n", (int)pid);
 381         kill(pid, SIGTERM);
 382 }
 383
 384 static void stop_rsync_process(void)
 385 {
 386         if (!rsync_pid || rsync_stopped)
 387                 return;
 388         kill(SIGSTOP, rsync_pid);
 389         rsync_stopped = 1;
 390 }
 391
 392 static void restart_rsync_process(void)
 393 {
 394         if (!rsync_pid || !rsync_stopped)
 395                 return;
 396         kill (SIGCONT, rsync_pid);
 397         rsync_stopped = 0;
 398 }
 399
 400
 401 /**
 402  * Print a log message about the exit status of a child.
 403  */
 404 static void log_termination_msg(pid_t pid, int status)
 405 {
 406         if (WIFEXITED(status))
 407                 DSS_INFO_LOG("child %i exited. Exit status: %i\n", (int)pid,
 408                         WEXITSTATUS(status));
 409         else if (WIFSIGNALED(status))
 410                 DSS_NOTICE_LOG("child %i was killed by signal %i\n", (int)pid,
 411                         WTERMSIG(status));
 412         else
 413                 DSS_WARNING_LOG("child %i terminated abormally\n", (int)pid);
 414 }
 415
 416 static int wait_for_process(pid_t pid, int *status)
 417 {
 418         int ret;
 419
 420         DSS_DEBUG_LOG("Waiting for process %d to terminate\n", (int)pid);
 421         for (;;) {
 422                 fd_set rfds;
 423
 424                 FD_ZERO(&rfds);
 425                 FD_SET(signal_pipe, &rfds);
 426                 ret = dss_select(signal_pipe + 1, &rfds, NULL, NULL);
 427                 if (ret < 0)
 428                         break;
 429                 ret = next_signal();
 430                 if (!ret)
 431                         continue;
 432                 if (ret == SIGCHLD) {
 433                         ret = waitpid(pid, status, 0);
 434                         if (ret >= 0)
 435                                 break;
 436                         if (errno != EINTR) { /* error */
 437                                 ret = -ERRNO_TO_DSS_ERROR(errno);
 438                                 break;
 439                         }
 440                 }
 441                 /* SIGINT or SIGTERM */
 442                 DSS_WARNING_LOG("sending SIGTERM to pid %d\n", (int)pid);
 443                 kill(pid, SIGTERM);
 444         }
 445         if (ret < 0)
 446                 DSS_ERROR_LOG("failed to wait for process %d\n", (int)pid);
 447         else
 448                 log_termination_msg(pid, *status);
 449         return ret;
 450 }
 451
 452 static int handle_rm_exit(int status)
 453 {
 454         rm_pid = 0;
 455         if (!WIFEXITED(status))
 456                 return -E_INVOLUNTARY_EXIT;
 457         if (WEXITSTATUS(status))
 458                 return -E_BAD_EXIT_CODE;
 459         return 1;
 460 }
 461
 462 static int wait_for_rm_process(void)
 463 {
 464         int status, ret = wait_for_process(rm_pid, &status);
 465
 466         if (ret < 0)
 467                 return ret;
 468         return handle_rm_exit(status);
 469 }
 470
 471 static int handle_rsync_exit(int status)
 472 {
 473         int es, ret;
 474
 475         if (!WIFEXITED(status)) {
 476                 DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)rsync_pid);
 477                 ret = -E_INVOLUNTARY_EXIT;
 478                 snapshot_creation_status = SCS_READY;
 479                 compute_next_snapshot_time();
 480                 goto out;
 481         }
 482         es = WEXITSTATUS(status);
 483         if (es != 0 && es != 23 && es != 24) {
 484                 DSS_ERROR_LOG("rsync process %d returned %d\n", (int)rsync_pid, es);
 485                 ret = -E_BAD_EXIT_CODE;
 486                 snapshot_creation_status = SCS_READY;
 487                 compute_next_snapshot_time();
 488                 goto out;
 489         }
 490         ret = rename_incomplete_snapshot(current_snapshot_creation_time);
 491         if (ret < 0)
 492                 goto out;
 493         snapshot_creation_status = SCS_RSYNC_SUCCESS;
 494 out:
 495         rsync_pid = 0;
 496         rsync_stopped = 0;
 497         return ret;
 498 }
 499
 500 static int handle_pre_create_hook_exit(int status)
 501 {
 502         int es, ret;
 503
 504         if (!WIFEXITED(status)) {
 505                 snapshot_creation_status = SCS_READY;
 506                 compute_next_snapshot_time();
 507                 ret = -E_INVOLUNTARY_EXIT;
 508                 goto out;
 509         }
 510         es = WEXITSTATUS(status);
 511         if (es) {
 512                 snapshot_creation_status = SCS_READY;
 513                 compute_next_snapshot_time();
 514                 ret = -E_BAD_EXIT_CODE;
 515                 goto out;
 516         }
 517         snapshot_creation_status = SCS_PRE_HOOK_SUCCESS;
 518         ret = 1;
 519 out:
 520         pre_create_hook_pid = 0;
 521         return ret;
 522 }
 523
 524 static int handle_sigchld(void)
 525 {
 526         pid_t pid;
 527         int status, ret = reap_child(&pid, &status);
 528
 529         if (ret <= 0)
 530                 return ret;
 531         if (pid == rsync_pid)
 532                 return handle_rsync_exit(status);
 533         if (pid == rm_pid)
 534                 return handle_rm_exit(status);
 535         if (pid == pre_create_hook_pid)
 536                 return handle_pre_create_hook_exit(status);
 537         if (pid == post_create_hook_pid) {
 538                 snapshot_creation_status = SCS_READY;
 539                 compute_next_snapshot_time();
 540                 return 1;
 541         }
 542         DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid);
 543         exit(EXIT_FAILURE);
 544 }
 545
 546
 547 static int check_config(void)
 548 {
 549         if (conf.unit_interval_arg <= 0) {
 550                 DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg);
 551                 return -E_INVALID_NUMBER;
 552         }
 553         DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg);
 554         if (conf.num_intervals_arg <= 0) {
 555                 DSS_ERROR_LOG("bad number of intervals  %i\n", conf.num_intervals_arg);
 556                 return -E_INVALID_NUMBER;
 557         }
 558         DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg);
 559         return 1;
 560 }
 561
 562 /* exits on errors */
 563 static void parse_config_file(int override)
 564 {
 565         int ret;
 566         char *config_file;
 567         struct stat statbuf;
 568         char *old_logfile_arg = NULL;
 569         int old_daemon_given = 0;
 570
 571         if (conf.config_file_given)
 572                 config_file = dss_strdup(conf.config_file_arg);
 573         else {
 574                 char *home = get_homedir();
 575                 config_file = make_message("%s/.dssrc", home);
 576                 free(home);
 577         }
 578         if (override) { /* SIGHUP */
 579                 if (conf.logfile_given)
 580                         old_logfile_arg = dss_strdup(conf.logfile_arg);
 581                 old_daemon_given = conf.daemon_given;
 582         }
 583
 584         ret = stat(config_file, &statbuf);
 585         if (ret && conf.config_file_given) {
 586                 ret = -ERRNO_TO_DSS_ERROR(errno);
 587                 DSS_ERROR_LOG("failed to stat config file %s\n", config_file);
 588                 goto out;
 589         }
 590         if (!ret) {
 591                 struct cmdline_parser_params params = {
 592                         .override = override,
 593                         .initialize = 0,
 594                         .check_required = 1,
 595                         .check_ambiguity = 0
 596                 };
 597                 cmdline_parser_config_file(config_file, &conf, &params);
 598         }
 599         ret = check_config();
 600         if (ret < 0)
 601                 goto out;
 602         if (override) {
 603                 /* don't change daemon mode on SIGHUP */
 604                 conf.daemon_given = old_daemon_given;
 605                 close_log(logfile);
 606                 logfile = NULL;
 607                 if (conf.logfile_given)
 608                         free(old_logfile_arg);
 609                 else if (conf.daemon_given) { /* re-use old logfile */
 610                         conf.logfile_arg = old_logfile_arg;
 611                         conf.logfile_given = 1;
 612                 }
 613         }
 614         if (conf.logfile_given) {
 615                 logfile = open_log(conf.logfile_arg);
 616                 log_welcome(conf.loglevel_arg);
 617         }
 618         DSS_EMERG_LOG("loglevel: %d\n", conf.loglevel_arg);
 619 //      cmdline_parser_dump(logfile? logfile : stdout, &conf);
 620         ret = dss_chdir(conf.dest_dir_arg);
 621 out:
 622         free(config_file);
 623         if (ret >= 0)
 624                 return;
 625         DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
 626         exit(EXIT_FAILURE);
 627 }
 628
 629 static void handle_sighup(void)
 630 {
 631         DSS_NOTICE_LOG("SIGHUP\n");
 632         parse_config_file(1);
 633 }
 634
 635 static void handle_signal(void)
 636 {
 637         int sig, ret = next_signal();
 638
 639         if (ret <= 0)
 640                 goto out;
 641         sig = ret;
 642         switch (sig) {
 643         case SIGINT:
 644         case SIGTERM:
 645                 restart_rsync_process();
 646                 kill_process(rsync_pid);
 647                 kill_process(rm_pid);
 648                 exit(EXIT_FAILURE);
 649         case SIGHUP:
 650                 handle_sighup();
 651                 ret = 1;
 652                 break;
 653         case SIGCHLD:
 654                 ret = handle_sigchld();
 655                 break;
 656         }
 657 out:
 658         if (ret < 0)
 659                 DSS_ERROR_LOG("%s\n", dss_strerror(-ret));
 660 }
 661
 662 static void create_rsync_argv(char ***argv, int64_t *num)
 663 {
 664         char *logname, *newest;
 665         int i = 0, j;
 666         struct snapshot_list sl;
 667
 668         dss_get_snapshot_list(&sl);
 669         newest = name_of_newest_complete_snapshot(&sl);
 670         free_snapshot_list(&sl);
 671
 672         *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
 673         (*argv)[i++] = dss_strdup("rsync");
 674         (*argv)[i++] = dss_strdup("-aq");
 675         (*argv)[i++] = dss_strdup("--delete");
 676         for (j = 0; j < conf.rsync_option_given; j++)
 677                 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
 678         if (newest) {
 679                 DSS_INFO_LOG("using %s as reference snapshot\n", newest);
 680                 (*argv)[i++] = make_message("--link-dest=../%s", newest);
 681                 free(newest);
 682         } else
 683                 DSS_INFO_LOG("no previous snapshot found\n");
 684         if (conf.exclude_patterns_given) {
 685                 (*argv)[i++] = dss_strdup("--exclude-from");
 686                 (*argv)[i++] = dss_strdup(conf.exclude_patterns_arg);
 687
 688         }
 689         logname = dss_logname();
 690         if (conf.remote_user_given && !strcmp(conf.remote_user_arg, logname))
 691                 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
 692         else
 693                 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
 694                         conf.remote_user_arg : logname,
 695                         conf.remote_host_arg, conf.source_dir_arg);
 696         free(logname);
 697         *num = get_current_time();
 698         (*argv)[i++] = incomplete_name(*num);
 699         (*argv)[i++] = NULL;
 700         for (j = 0; j < i; j++)
 701                 DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]);
 702 }
 703
 704 static void free_rsync_argv(char **argv)
 705 {
 706         int i;
 707         for (i = 0; argv[i]; i++)
 708                 free(argv[i]);
 709         free(argv);
 710 }
 711
 712 static int create_snapshot(char **argv)
 713 {
 714         int ret, fds[3] = {0, 0, 0};
 715         char *name;
 716
 717         name = incomplete_name(current_snapshot_creation_time);
 718         DSS_NOTICE_LOG("creating new snapshot %s\n", name);
 719         free(name);
 720         ret = dss_exec(&rsync_pid, argv[0], argv, fds);
 721         if (ret < 0)
 722                 return ret;
 723         snapshot_creation_status = SCS_RSYNC_RUNNING;
 724         return ret;
 725 }
 726
 727 static int select_loop(void)
 728 {
 729         int ret;
 730         struct timeval tv = {.tv_sec = 0, .tv_usec = 0};
 731
 732         for (;;) {
 733                 fd_set rfds;
 734                 int low_disk_space;
 735                 char **rsync_argv;
 736                 struct timeval now, *tvp = &tv;
 737
 738                 if (rsync_pid)
 739                         tv.tv_sec = 60; /* check every 60 seconds for free disk space */
 740                 else if (rm_pid)
 741                         tvp = NULL; /* sleep until rm process dies */
 742                 FD_ZERO(&rfds);
 743                 FD_SET(signal_pipe, &rfds);
 744                 DSS_DEBUG_LOG("tvp: %p, tv_sec: %lu\n", tvp, (long unsigned) tv.tv_sec);
 745                 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
 746                 if (ret < 0)
 747                         return ret;
 748                 if (FD_ISSET(signal_pipe, &rfds))
 749                         handle_signal();
 750                 if (rm_pid)
 751                         continue;
 752                 ret = disk_space_low();
 753                 if (ret < 0)
 754                         break;
 755                 low_disk_space = ret;
 756                 ret = try_to_free_disk_space(low_disk_space);
 757                 if (ret < 0)
 758                         break;
 759                 if (rm_pid) {
 760                         stop_rsync_process();
 761                         continue;
 762                 }
 763                 restart_rsync_process();
 764                 gettimeofday(&now, NULL);
 765                 if (tv_diff(&next_snapshot_time, &now, &tv) > 0)
 766                         continue;
 767                 switch (snapshot_creation_status) {
 768                 case SCS_READY:
 769                         ret = pre_create_hook();
 770                         if (ret < 0)
 771                                 goto out;
 772                         continue;
 773                 case SCS_PRE_HOOK_RUNNING:
 774                         continue;
 775                 case SCS_PRE_HOOK_SUCCESS:
 776                         create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 777                         ret = create_snapshot(rsync_argv);
 778                         free_rsync_argv(rsync_argv);
 779                         if (ret < 0)
 780                                 goto out;
 781                         continue;
 782                 case SCS_RSYNC_RUNNING:
 783                         continue;
 784                 case SCS_RSYNC_SUCCESS:
 785                         ret = post_create_hook();
 786                         if (ret < 0)
 787                                 goto out;
 788                         continue;
 789                 case SCS_POST_HOOK_RUNNING:
 790                         continue;
 791                 }
 792         }
 793 out:
 794         return ret;
 795 }
 796
 797 static int com_run(void)
 798 {
 799         int ret;
 800
 801         if (conf.dry_run_given) {
 802                 DSS_ERROR_LOG("dry_run not supported by this command\n");
 803                 return -E_SYNTAX;
 804         }
 805         ret = install_sighandler(SIGHUP);
 806         if (ret < 0)
 807                 return ret;
 808         compute_next_snapshot_time();
 809         return select_loop();
 810 }
 811
 812 static int com_prune(void)
 813 {
 814         int ret;
 815         struct snapshot_list sl;
 816         struct disk_space ds;
 817
 818         ret = get_disk_space(".", &ds);
 819         if (ret < 0)
 820                 return ret;
 821         log_disk_space(&ds);
 822         for (;;) {
 823                 dss_get_snapshot_list(&sl);
 824                 ret = remove_outdated_snapshot(&sl);
 825                 free_snapshot_list(&sl);
 826                 if (ret < 0)
 827                         return ret;
 828                 if (!ret)
 829                         break;
 830                 ret = wait_for_rm_process();
 831                 if (ret < 0)
 832                         goto out;
 833         }
 834         for (;;) {
 835                 dss_get_snapshot_list(&sl);
 836                 ret = remove_redundant_snapshot(&sl);
 837                 free_snapshot_list(&sl);
 838                 if (ret < 0)
 839                         return ret;
 840                 if (!ret)
 841                         break;
 842                 ret = wait_for_rm_process();
 843                 if (ret < 0)
 844                         goto out;
 845         }
 846         return 1;
 847 out:
 848         return ret;
 849 }
 850
 851 static int com_create(void)
 852 {
 853         int ret, status;
 854         char **rsync_argv;
 855
 856         if (conf.dry_run_given) {
 857                 int i;
 858                 char *msg = NULL;
 859                 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 860                 for (i = 0; rsync_argv[i]; i++) {
 861                         char *tmp = msg;
 862                         msg = make_message("%s%s%s", tmp? tmp : "",
 863                                 tmp? " " : "", rsync_argv[i]);
 864                         free(tmp);
 865                 }
 866                 free_rsync_argv(rsync_argv);
 867                 dss_msg("%s\n", msg);
 868                 free(msg);
 869                 return 1;
 870         }
 871         ret = pre_create_hook();
 872         if (ret < 0)
 873                 return ret;
 874         if (pre_create_hook_pid) {
 875                 ret = wait_for_process(pre_create_hook_pid, &status);
 876                 if (ret < 0)
 877                         return ret;
 878                 ret = handle_pre_create_hook_exit(status);
 879                 if (ret < 0)
 880                         return ret;
 881         }
 882         create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 883         ret = create_snapshot(rsync_argv);
 884         if (ret < 0)
 885                 goto out;
 886         ret = wait_for_process(rsync_pid, &status);
 887         if (ret < 0)
 888                 goto out;
 889         ret = handle_rsync_exit(status);
 890         if (ret < 0)
 891                 goto out;
 892         post_create_hook();
 893         if (post_create_hook_pid)
 894                 ret = wait_for_process(post_create_hook_pid, &status);
 895 out:
 896         free_rsync_argv(rsync_argv);
 897         return ret;
 898 }
 899
 900 static int com_ls(void)
 901 {
 902         int i;
 903         struct snapshot_list sl;
 904         struct snapshot *s;
 905
 906         dss_get_snapshot_list(&sl);
 907         FOR_EACH_SNAPSHOT(s, i, &sl)
 908                 dss_msg("%u\t%s\n", s->interval, s->name);
 909         free_snapshot_list(&sl);
 910         return 1;
 911 }
 912
 913 static void setup_signal_handling(void)
 914 {
 915         int ret;
 916
 917         DSS_INFO_LOG("setting up signal handlers\n");
 918         signal_pipe = signal_init(); /* always successful */
 919         ret = install_sighandler(SIGINT);
 920         if (ret < 0)
 921                 goto err;
 922         ret = install_sighandler(SIGTERM);
 923         if (ret < 0)
 924                 goto err;
 925         ret = install_sighandler(SIGCHLD);
 926         if (ret < 0)
 927                 goto err;
 928         return;
 929 err:
 930         DSS_EMERG_LOG("could not install signal handlers\n");
 931         exit(EXIT_FAILURE);
 932 }
 933
 934
 935 int main(int argc, char **argv)
 936 {
 937         int ret;
 938         struct cmdline_parser_params params = {
 939                 .override = 0,
 940                 .initialize = 1,
 941                 .check_required = 0,
 942                 .check_ambiguity = 0
 943         };
 944
 945         cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
 946         parse_config_file(0);
 947
 948         if (conf.daemon_given)
 949                 daemon_init();
 950         setup_signal_handling();
 951         ret = call_command_handler();
 952         if (ret < 0)
 953                 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
 954         exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
 955 }