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 struct timeval next_snapshot_time;
  45 /** The pid of the pre-create hook. */
  46 pid_t pre_create_hook_pid;
  47 /** The pid of the post-create hook. */
  48 pid_t post_create_hook_pid;
  49 /* Creation time of the snapshot currently being created. */
  50 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) int com_ ##x(void);
  67 COMMANDS
  68 #undef COMMAND
  69 #define COMMAND(x) if (conf.x ##_given) return com_ ##x();
  70 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 __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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 int handle_rm_exit(int status)
 452 {
 453         rm_pid = 0;
 454         if (!WIFEXITED(status))
 455                 return -E_INVOLUNTARY_EXIT;
 456         if (WEXITSTATUS(status))
 457                 return -E_BAD_EXIT_CODE;
 458         return 1;
 459 }
 460
 461 int wait_for_rm_process(void)
 462 {
 463         int status, ret = wait_for_process(rm_pid, &status);
 464
 465         if (ret < 0)
 466                 return ret;
 467         return handle_rm_exit(status);
 468 }
 469
 470 int handle_rsync_exit(int status)
 471 {
 472         int es, ret;
 473
 474         if (!WIFEXITED(status)) {
 475                 DSS_ERROR_LOG("rsync process %d died involuntary\n", (int)rsync_pid);
 476                 ret = -E_INVOLUNTARY_EXIT;
 477                 snapshot_creation_status = SCS_READY;
 478                 compute_next_snapshot_time();
 479                 goto out;
 480         }
 481         es = WEXITSTATUS(status);
 482         if (es != 0 && es != 23 && es != 24) {
 483                 DSS_ERROR_LOG("rsync process %d returned %d\n", (int)rsync_pid, es);
 484                 ret = -E_BAD_EXIT_CODE;
 485                 snapshot_creation_status = SCS_READY;
 486                 compute_next_snapshot_time();
 487                 goto out;
 488         }
 489         ret = rename_incomplete_snapshot(current_snapshot_creation_time);
 490         if (ret < 0)
 491                 goto out;
 492         snapshot_creation_status = SCS_RSYNC_SUCCESS;
 493 out:
 494         rsync_pid = 0;
 495         rsync_stopped = 0;
 496         return ret;
 497 }
 498
 499 int handle_pre_create_hook_exit(int status)
 500 {
 501         int es, ret;
 502
 503         if (!WIFEXITED(status)) {
 504                 snapshot_creation_status = SCS_READY;
 505                 compute_next_snapshot_time();
 506                 ret = -E_INVOLUNTARY_EXIT;
 507                 goto out;
 508         }
 509         es = WEXITSTATUS(status);
 510         if (es) {
 511                 snapshot_creation_status = SCS_READY;
 512                 compute_next_snapshot_time();
 513                 ret = -E_BAD_EXIT_CODE;
 514                 goto out;
 515         }
 516         snapshot_creation_status = SCS_PRE_HOOK_SUCCESS;
 517         ret = 1;
 518 out:
 519         pre_create_hook_pid = 0;
 520         return ret;
 521 }
 522
 523 int handle_sigchld(void)
 524 {
 525         pid_t pid;
 526         int status, ret = reap_child(&pid, &status);
 527
 528         if (ret <= 0)
 529                 return ret;
 530         if (pid == rsync_pid)
 531                 return handle_rsync_exit(status);
 532         if (pid == rm_pid)
 533                 return handle_rm_exit(status);
 534         if (pid == pre_create_hook_pid)
 535                 return handle_pre_create_hook_exit(status);
 536         if (pid == post_create_hook_pid) {
 537                 snapshot_creation_status = SCS_READY;
 538                 compute_next_snapshot_time();
 539                 return 1;
 540         }
 541         DSS_EMERG_LOG("BUG: unknown process %d died\n", (int)pid);
 542         exit(EXIT_FAILURE);
 543 }
 544
 545
 546 int check_config(void)
 547 {
 548         if (conf.unit_interval_arg <= 0) {
 549                 DSS_ERROR_LOG("bad unit interval: %i\n", conf.unit_interval_arg);
 550                 return -E_INVALID_NUMBER;
 551         }
 552         DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg);
 553         if (conf.num_intervals_arg <= 0) {
 554                 DSS_ERROR_LOG("bad number of intervals  %i\n", conf.num_intervals_arg);
 555                 return -E_INVALID_NUMBER;
 556         }
 557         DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg);
 558         return 1;
 559 }
 560
 561 /* exits on errors */
 562 void parse_config_file(int override)
 563 {
 564         int ret;
 565         char *config_file;
 566         struct stat statbuf;
 567         char *old_logfile_arg = NULL;
 568         int old_daemon_given = 0;
 569
 570         if (conf.config_file_given)
 571                 config_file = dss_strdup(conf.config_file_arg);
 572         else {
 573                 char *home = get_homedir();
 574                 config_file = make_message("%s/.dssrc", home);
 575                 free(home);
 576         }
 577         if (override) { /* SIGHUP */
 578                 if (conf.logfile_given)
 579                         old_logfile_arg = dss_strdup(conf.logfile_arg);
 580                 old_daemon_given = conf.daemon_given;
 581         }
 582
 583         ret = stat(config_file, &statbuf);
 584         if (ret && conf.config_file_given) {
 585                 ret = -ERRNO_TO_DSS_ERROR(errno);
 586                 DSS_ERROR_LOG("failed to stat config file %s\n", config_file);
 587                 goto out;
 588         }
 589         if (!ret) {
 590                 struct cmdline_parser_params params = {
 591                         .override = override,
 592                         .initialize = 0,
 593                         .check_required = 1,
 594                         .check_ambiguity = 0
 595                 };
 596                 cmdline_parser_config_file(config_file, &conf, &params);
 597         }
 598         ret = check_config();
 599         if (ret < 0)
 600                 goto out;
 601         if (override) {
 602                 /* don't change daemon mode on SIGHUP */
 603                 conf.daemon_given = old_daemon_given;
 604                 close_log(logfile);
 605                 logfile = NULL;
 606                 if (conf.logfile_given)
 607                         free(old_logfile_arg);
 608                 else if (conf.daemon_given) { /* re-use old logfile */
 609                         conf.logfile_arg = old_logfile_arg;
 610                         conf.logfile_given = 1;
 611                 }
 612         }
 613         if (conf.logfile_given) {
 614                 logfile = open_log(conf.logfile_arg);
 615                 log_welcome(conf.loglevel_arg);
 616         }
 617         DSS_EMERG_LOG("loglevel: %d\n", conf.loglevel_arg);
 618 //      cmdline_parser_dump(logfile? logfile : stdout, &conf);
 619         ret = dss_chdir(conf.dest_dir_arg);
 620 out:
 621         free(config_file);
 622         if (ret >= 0)
 623                 return;
 624         DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
 625         exit(EXIT_FAILURE);
 626 }
 627
 628 void handle_sighup(void)
 629 {
 630         DSS_NOTICE_LOG("SIGHUP\n");
 631         parse_config_file(1);
 632 }
 633
 634 void handle_signal(void)
 635 {
 636         int sig, ret = next_signal();
 637
 638         if (ret <= 0)
 639                 goto out;
 640         sig = ret;
 641         switch (sig) {
 642         case SIGINT:
 643         case SIGTERM:
 644                 restart_rsync_process();
 645                 kill_process(rsync_pid);
 646                 kill_process(rm_pid);
 647                 exit(EXIT_FAILURE);
 648         case SIGHUP:
 649                 handle_sighup();
 650                 ret = 1;
 651                 break;
 652         case SIGCHLD:
 653                 ret = handle_sigchld();
 654                 break;
 655         }
 656 out:
 657         if (ret < 0)
 658                 DSS_ERROR_LOG("%s\n", dss_strerror(-ret));
 659 }
 660
 661 void create_rsync_argv(char ***argv, int64_t *num)
 662 {
 663         char *logname, *newest;
 664         int i = 0, j;
 665         struct snapshot_list sl;
 666
 667         dss_get_snapshot_list(&sl);
 668         newest = name_of_newest_complete_snapshot(&sl);
 669         free_snapshot_list(&sl);
 670
 671         *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
 672         (*argv)[i++] = dss_strdup("rsync");
 673         (*argv)[i++] = dss_strdup("-aq");
 674         (*argv)[i++] = dss_strdup("--delete");
 675         for (j = 0; j < conf.rsync_option_given; j++)
 676                 (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
 677         if (newest) {
 678                 DSS_INFO_LOG("using %s as reference snapshot\n", newest);
 679                 (*argv)[i++] = make_message("--link-dest=../%s", newest);
 680                 free(newest);
 681         } else
 682                 DSS_INFO_LOG("no previous snapshot found\n");
 683         if (conf.exclude_patterns_given) {
 684                 (*argv)[i++] = dss_strdup("--exclude-from");
 685                 (*argv)[i++] = dss_strdup(conf.exclude_patterns_arg);
 686
 687         }
 688         logname = dss_logname();
 689         if (conf.remote_user_given && !strcmp(conf.remote_user_arg, logname))
 690                 (*argv)[i++] = dss_strdup(conf.source_dir_arg);
 691         else
 692                 (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
 693                         conf.remote_user_arg : logname,
 694                         conf.remote_host_arg, conf.source_dir_arg);
 695         free(logname);
 696         *num = get_current_time();
 697         (*argv)[i++] = incomplete_name(*num);
 698         (*argv)[i++] = NULL;
 699         for (j = 0; j < i; j++)
 700                 DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]);
 701 }
 702
 703 void free_rsync_argv(char **argv)
 704 {
 705         int i;
 706         for (i = 0; argv[i]; i++)
 707                 free(argv[i]);
 708         free(argv);
 709 }
 710
 711 int create_snapshot(char **argv)
 712 {
 713         int ret, fds[3] = {0, 0, 0};
 714         char *name;
 715
 716         name = incomplete_name(current_snapshot_creation_time);
 717         DSS_NOTICE_LOG("creating new snapshot %s\n", name);
 718         free(name);
 719         ret = dss_exec(&rsync_pid, argv[0], argv, fds);
 720         if (ret < 0)
 721                 return ret;
 722         snapshot_creation_status = SCS_RSYNC_RUNNING;
 723         return ret;
 724 }
 725
 726 int select_loop(void)
 727 {
 728         int ret;
 729         struct timeval tv = {.tv_sec = 0, .tv_usec = 0};
 730
 731         for (;;) {
 732                 fd_set rfds;
 733                 int low_disk_space;
 734                 char **rsync_argv;
 735                 struct timeval now, *tvp = &tv;
 736
 737                 if (rsync_pid)
 738                         tv.tv_sec = 60; /* check every 60 seconds for free disk space */
 739                 else if (rm_pid)
 740                         tvp = NULL; /* sleep until rm process dies */
 741                 FD_ZERO(&rfds);
 742                 FD_SET(signal_pipe, &rfds);
 743                 DSS_DEBUG_LOG("tvp: %p, tv_sec: %lu\n", tvp, (long unsigned) tv.tv_sec);
 744                 ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp);
 745                 if (ret < 0)
 746                         return ret;
 747                 if (FD_ISSET(signal_pipe, &rfds))
 748                         handle_signal();
 749                 if (rm_pid)
 750                         continue;
 751                 ret = disk_space_low();
 752                 if (ret < 0)
 753                         break;
 754                 low_disk_space = ret;
 755                 ret = try_to_free_disk_space(low_disk_space);
 756                 if (ret < 0)
 757                         break;
 758                 if (rm_pid) {
 759                         stop_rsync_process();
 760                         continue;
 761                 }
 762                 restart_rsync_process();
 763                 gettimeofday(&now, NULL);
 764                 if (tv_diff(&next_snapshot_time, &now, &tv) > 0)
 765                         continue;
 766                 switch (snapshot_creation_status) {
 767                 case SCS_READY:
 768                         ret = pre_create_hook();
 769                         if (ret < 0)
 770                                 goto out;
 771                         continue;
 772                 case SCS_PRE_HOOK_RUNNING:
 773                         continue;
 774                 case SCS_PRE_HOOK_SUCCESS:
 775                         create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 776                         ret = create_snapshot(rsync_argv);
 777                         free_rsync_argv(rsync_argv);
 778                         if (ret < 0)
 779                                 goto out;
 780                         continue;
 781                 case SCS_RSYNC_RUNNING:
 782                         continue;
 783                 case SCS_RSYNC_SUCCESS:
 784                         ret = post_create_hook();
 785                         if (ret < 0)
 786                                 goto out;
 787                         continue;
 788                 case SCS_POST_HOOK_RUNNING:
 789                         continue;
 790                 }
 791         }
 792 out:
 793         return ret;
 794 }
 795
 796 int com_run(void)
 797 {
 798         int ret;
 799
 800         if (conf.dry_run_given) {
 801                 DSS_ERROR_LOG("dry_run not supported by this command\n");
 802                 return -E_SYNTAX;
 803         }
 804         ret = install_sighandler(SIGHUP);
 805         if (ret < 0)
 806                 return ret;
 807         compute_next_snapshot_time();
 808         return select_loop();
 809 }
 810
 811 int com_prune(void)
 812 {
 813         int ret;
 814         struct snapshot_list sl;
 815         struct disk_space ds;
 816
 817         ret = get_disk_space(".", &ds);
 818         if (ret < 0)
 819                 return ret;
 820         log_disk_space(&ds);
 821         for (;;) {
 822                 dss_get_snapshot_list(&sl);
 823                 ret = remove_outdated_snapshot(&sl);
 824                 free_snapshot_list(&sl);
 825                 if (ret < 0)
 826                         return ret;
 827                 if (!ret)
 828                         break;
 829                 ret = wait_for_rm_process();
 830                 if (ret < 0)
 831                         goto out;
 832         }
 833         for (;;) {
 834                 dss_get_snapshot_list(&sl);
 835                 ret = remove_redundant_snapshot(&sl);
 836                 free_snapshot_list(&sl);
 837                 if (ret < 0)
 838                         return ret;
 839                 if (!ret)
 840                         break;
 841                 ret = wait_for_rm_process();
 842                 if (ret < 0)
 843                         goto out;
 844         }
 845         return 1;
 846 out:
 847         return ret;
 848 }
 849
 850 int com_create(void)
 851 {
 852         int ret, status;
 853         char **rsync_argv;
 854
 855         if (conf.dry_run_given) {
 856                 int i;
 857                 char *msg = NULL;
 858                 create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 859                 for (i = 0; rsync_argv[i]; i++) {
 860                         char *tmp = msg;
 861                         msg = make_message("%s%s%s", tmp? tmp : "",
 862                                 tmp? " " : "", rsync_argv[i]);
 863                         free(tmp);
 864                 }
 865                 free_rsync_argv(rsync_argv);
 866                 dss_msg("%s\n", msg);
 867                 free(msg);
 868                 return 1;
 869         }
 870         ret = pre_create_hook();
 871         if (ret < 0)
 872                 return ret;
 873         if (pre_create_hook_pid) {
 874                 ret = wait_for_process(pre_create_hook_pid, &status);
 875                 if (ret < 0)
 876                         return ret;
 877                 ret = handle_pre_create_hook_exit(status);
 878                 if (ret < 0)
 879                         return ret;
 880         }
 881         create_rsync_argv(&rsync_argv, &current_snapshot_creation_time);
 882         ret = create_snapshot(rsync_argv);
 883         if (ret < 0)
 884                 goto out;
 885         ret = wait_for_process(rsync_pid, &status);
 886         if (ret < 0)
 887                 goto out;
 888         ret = handle_rsync_exit(status);
 889         if (ret < 0)
 890                 goto out;
 891         post_create_hook();
 892         if (post_create_hook_pid)
 893                 ret = wait_for_process(post_create_hook_pid, &status);
 894 out:
 895         free_rsync_argv(rsync_argv);
 896         return ret;
 897 }
 898
 899 int com_ls(void)
 900 {
 901         int i;
 902         struct snapshot_list sl;
 903         struct snapshot *s;
 904
 905         dss_get_snapshot_list(&sl);
 906         FOR_EACH_SNAPSHOT(s, i, &sl)
 907                 dss_msg("%u\t%s\n", s->interval, s->name);
 908         free_snapshot_list(&sl);
 909         return 1;
 910 }
 911
 912 static void setup_signal_handling(void)
 913 {
 914         int ret;
 915
 916         DSS_INFO_LOG("setting up signal handlers\n");
 917         signal_pipe = signal_init(); /* always successful */
 918         ret = install_sighandler(SIGINT);
 919         if (ret < 0)
 920                 goto err;
 921         ret = install_sighandler(SIGTERM);
 922         if (ret < 0)
 923                 goto err;
 924         ret = install_sighandler(SIGCHLD);
 925         if (ret < 0)
 926                 goto err;
 927         return;
 928 err:
 929         DSS_EMERG_LOG("could not install signal handlers\n");
 930         exit(EXIT_FAILURE);
 931 }
 932
 933
 934 int main(int argc, char **argv)
 935 {
 936         int ret;
 937         struct cmdline_parser_params params = {
 938                 .override = 0,
 939                 .initialize = 1,
 940                 .check_required = 0,
 941                 .check_ambiguity = 0
 942         };
 943
 944         cmdline_parser_ext(argc, argv, &conf, &params); /* aborts on errors */
 945         parse_config_file(0);
 946
 947         if (conf.daemon_given)
 948                 daemon_init();
 949         setup_signal_handling();
 950         ret = call_command_handler();
 951         if (ret < 0)
 952                 DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
 953         exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
 954 }