src/unit.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <sys/epoll.h>
  26 #include <sys/timerfd.h>
  27 #include <sys/poll.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30
  31 #include "set.h"
  32 #include "unit.h"
  33 #include "macro.h"
  34 #include "strv.h"
  35 #include "load-fragment.h"
  36 #include "load-dropin.h"
  37 #include "log.h"
  38 #include "unit-name.h"
  39 #include "specifier.h"
  40 #include "dbus-unit.h"
  41 #include "special.h"
  42 #include "cgroup-util.h"
  43
  44 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  45         [UNIT_SERVICE] = &service_vtable,
  46         [UNIT_TIMER] = &timer_vtable,
  47         [UNIT_SOCKET] = &socket_vtable,
  48         [UNIT_TARGET] = &target_vtable,
  49         [UNIT_DEVICE] = &device_vtable,
  50         [UNIT_MOUNT] = &mount_vtable,
  51         [UNIT_AUTOMOUNT] = &automount_vtable,
  52         [UNIT_SNAPSHOT] = &snapshot_vtable,
  53         [UNIT_SWAP] = &swap_vtable,
  54         [UNIT_PATH] = &path_vtable
  55 };
  56
  57 Unit *unit_new(Manager *m) {
  58         Unit *u;
  59
  60         assert(m);
  61
  62         if (!(u = new0(Unit, 1)))
  63                 return NULL;
  64
  65         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  66                 free(u);
  67                 return NULL;
  68         }
  69
  70         u->meta.manager = m;
  71         u->meta.type = _UNIT_TYPE_INVALID;
  72         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  73         u->meta.default_dependencies = true;
  74
  75         return u;
  76 }
  77
  78 bool unit_has_name(Unit *u, const char *name) {
  79         assert(u);
  80         assert(name);
  81
  82         return !!set_get(u->meta.names, (char*) name);
  83 }
  84
  85 int unit_add_name(Unit *u, const char *text) {
  86         UnitType t;
  87         char *s, *i = NULL;
  88         int r;
  89
  90         assert(u);
  91         assert(text);
  92
  93         if (unit_name_is_template(text)) {
  94                 if (!u->meta.instance)
  95                         return -EINVAL;
  96
  97                 s = unit_name_replace_instance(text, u->meta.instance);
  98         } else
  99                 s = strdup(text);
 100
 101         if (!s)
 102                 return -ENOMEM;
 103
 104         if (!unit_name_is_valid(s)) {
 105                 r = -EINVAL;
 106                 goto fail;
 107         }
 108
 109         assert_se((t = unit_name_to_type(s)) >= 0);
 110
 111         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 112                 r = -EINVAL;
 113                 goto fail;
 114         }
 115
 116         if ((r = unit_name_to_instance(s, &i)) < 0)
 117                 goto fail;
 118
 119         if (i && unit_vtable[t]->no_instances)
 120                 goto fail;
 121
 122         /* Ensure that this unit is either instanced or not instanced,
 123          * but not both. */
 124         if (u->meta.type != _UNIT_TYPE_INVALID && !u->meta.instance != !i) {
 125                 r = -EINVAL;
 126                 goto fail;
 127         }
 128
 129         if (unit_vtable[t]->no_alias &&
 130             !set_isempty(u->meta.names) &&
 131             !set_get(u->meta.names, s)) {
 132                 r = -EEXIST;
 133                 goto fail;
 134         }
 135
 136         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 137                 r = -E2BIG;
 138                 goto fail;
 139         }
 140
 141         if ((r = set_put(u->meta.names, s)) < 0) {
 142                 if (r == -EEXIST)
 143                         r = 0;
 144                 goto fail;
 145         }
 146
 147         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 148                 set_remove(u->meta.names, s);
 149                 goto fail;
 150         }
 151
 152         if (u->meta.type == _UNIT_TYPE_INVALID) {
 153
 154                 u->meta.type = t;
 155                 u->meta.id = s;
 156                 u->meta.instance = i;
 157
 158                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 159
 160                 if (UNIT_VTABLE(u)->init)
 161                         UNIT_VTABLE(u)->init(u);
 162         } else
 163                 free(i);
 164
 165         unit_add_to_dbus_queue(u);
 166         return 0;
 167
 168 fail:
 169         free(s);
 170         free(i);
 171
 172         return r;
 173 }
 174
 175 int unit_choose_id(Unit *u, const char *name) {
 176         char *s, *t = NULL, *i;
 177         int r;
 178
 179         assert(u);
 180         assert(name);
 181
 182         if (unit_name_is_template(name)) {
 183
 184                 if (!u->meta.instance)
 185                         return -EINVAL;
 186
 187                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 188                         return -ENOMEM;
 189
 190                 name = t;
 191         }
 192
 193         /* Selects one of the names of this unit as the id */
 194         s = set_get(u->meta.names, (char*) name);
 195         free(t);
 196
 197         if (!s)
 198                 return -ENOENT;
 199
 200         if ((r = unit_name_to_instance(s, &i)) < 0)
 201                 return r;
 202
 203         u->meta.id = s;
 204
 205         free(u->meta.instance);
 206         u->meta.instance = i;
 207
 208         unit_add_to_dbus_queue(u);
 209
 210         return 0;
 211 }
 212
 213 int unit_set_description(Unit *u, const char *description) {
 214         char *s;
 215
 216         assert(u);
 217
 218         if (!(s = strdup(description)))
 219                 return -ENOMEM;
 220
 221         free(u->meta.description);
 222         u->meta.description = s;
 223
 224         unit_add_to_dbus_queue(u);
 225         return 0;
 226 }
 227
 228 bool unit_check_gc(Unit *u) {
 229         assert(u);
 230
 231         if (u->meta.load_state == UNIT_STUB)
 232                 return true;
 233
 234         if (UNIT_VTABLE(u)->no_gc)
 235                 return true;
 236
 237         if (u->meta.job)
 238                 return true;
 239
 240         if (unit_active_state(u) != UNIT_INACTIVE)
 241                 return true;
 242
 243         if (UNIT_VTABLE(u)->check_gc)
 244                 if (UNIT_VTABLE(u)->check_gc(u))
 245                         return true;
 246
 247         return false;
 248 }
 249
 250 void unit_add_to_load_queue(Unit *u) {
 251         assert(u);
 252         assert(u->meta.type != _UNIT_TYPE_INVALID);
 253
 254         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 255                 return;
 256
 257         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 258         u->meta.in_load_queue = true;
 259 }
 260
 261 void unit_add_to_cleanup_queue(Unit *u) {
 262         assert(u);
 263
 264         if (u->meta.in_cleanup_queue)
 265                 return;
 266
 267         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 268         u->meta.in_cleanup_queue = true;
 269 }
 270
 271 void unit_add_to_gc_queue(Unit *u) {
 272         assert(u);
 273
 274         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 275                 return;
 276
 277         if (unit_check_gc(u))
 278                 return;
 279
 280         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 281         u->meta.in_gc_queue = true;
 282
 283         u->meta.manager->n_in_gc_queue ++;
 284
 285         if (u->meta.manager->gc_queue_timestamp <= 0)
 286                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 287 }
 288
 289 void unit_add_to_dbus_queue(Unit *u) {
 290         assert(u);
 291         assert(u->meta.type != _UNIT_TYPE_INVALID);
 292
 293         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 294                 return;
 295
 296         /* Shortcut things if nobody cares */
 297         if (!bus_has_subscriber(u->meta.manager)) {
 298                 u->meta.sent_dbus_new_signal = true;
 299                 return;
 300         }
 301
 302         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 303         u->meta.in_dbus_queue = true;
 304 }
 305
 306 static void bidi_set_free(Unit *u, Set *s) {
 307         Iterator i;
 308         Unit *other;
 309
 310         assert(u);
 311
 312         /* Frees the set and makes sure we are dropped from the
 313          * inverse pointers */
 314
 315         SET_FOREACH(other, s, i) {
 316                 UnitDependency d;
 317
 318                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 319                         set_remove(other->meta.dependencies[d], u);
 320
 321                 unit_add_to_gc_queue(other);
 322         }
 323
 324         set_free(s);
 325 }
 326
 327 void unit_free(Unit *u) {
 328         UnitDependency d;
 329         Iterator i;
 330         char *t;
 331
 332         assert(u);
 333
 334         bus_unit_send_removed_signal(u);
 335
 336         if (u->meta.load_state != UNIT_STUB)
 337                 if (UNIT_VTABLE(u)->done)
 338                         UNIT_VTABLE(u)->done(u);
 339
 340         SET_FOREACH(t, u->meta.names, i)
 341                 hashmap_remove_value(u->meta.manager->units, t, u);
 342
 343         if (u->meta.job)
 344                 job_free(u->meta.job);
 345
 346         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 347                 bidi_set_free(u, u->meta.dependencies[d]);
 348
 349         if (u->meta.type != _UNIT_TYPE_INVALID)
 350                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 351
 352         if (u->meta.in_load_queue)
 353                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 354
 355         if (u->meta.in_dbus_queue)
 356                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 357
 358         if (u->meta.in_cleanup_queue)
 359                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 360
 361         if (u->meta.in_gc_queue) {
 362                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 363                 u->meta.manager->n_in_gc_queue--;
 364         }
 365
 366         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 367
 368         free(u->meta.description);
 369         free(u->meta.fragment_path);
 370
 371         set_free_free(u->meta.names);
 372
 373         free(u->meta.instance);
 374
 375         free(u);
 376 }
 377
 378 UnitActiveState unit_active_state(Unit *u) {
 379         assert(u);
 380
 381         if (u->meta.load_state == UNIT_MERGED)
 382                 return unit_active_state(unit_follow_merge(u));
 383
 384         /* After a reload it might happen that a unit is not correctly
 385          * loaded but still has a process around. That's why we won't
 386          * shortcut failed loading to UNIT_INACTIVE_MAINTENANCE. */
 387
 388         return UNIT_VTABLE(u)->active_state(u);
 389 }
 390
 391 const char* unit_sub_state_to_string(Unit *u) {
 392         assert(u);
 393
 394         return UNIT_VTABLE(u)->sub_state_to_string(u);
 395 }
 396
 397 static void complete_move(Set **s, Set **other) {
 398         assert(s);
 399         assert(other);
 400
 401         if (!*other)
 402                 return;
 403
 404         if (*s)
 405                 set_move(*s, *other);
 406         else {
 407                 *s = *other;
 408                 *other = NULL;
 409         }
 410 }
 411
 412 static void merge_names(Unit *u, Unit *other) {
 413         char *t;
 414         Iterator i;
 415
 416         assert(u);
 417         assert(other);
 418
 419         complete_move(&u->meta.names, &other->meta.names);
 420
 421         set_free_free(other->meta.names);
 422         other->meta.names = NULL;
 423         other->meta.id = NULL;
 424
 425         SET_FOREACH(t, u->meta.names, i)
 426                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 427 }
 428
 429 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 430         Iterator i;
 431         Unit *back;
 432         int r;
 433
 434         assert(u);
 435         assert(other);
 436         assert(d < _UNIT_DEPENDENCY_MAX);
 437
 438         SET_FOREACH(back, other->meta.dependencies[d], i) {
 439                 UnitDependency k;
 440
 441                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 442                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 443
 444                                 if (r == -EEXIST)
 445                                         set_remove(back->meta.dependencies[k], other);
 446                                 else
 447                                         assert(r == -ENOENT);
 448                         }
 449         }
 450
 451         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 452
 453         set_free(other->meta.dependencies[d]);
 454         other->meta.dependencies[d] = NULL;
 455 }
 456
 457 int unit_merge(Unit *u, Unit *other) {
 458         UnitDependency d;
 459
 460         assert(u);
 461         assert(other);
 462         assert(u->meta.manager == other->meta.manager);
 463         assert(u->meta.type != _UNIT_TYPE_INVALID);
 464
 465         other = unit_follow_merge(other);
 466
 467         if (other == u)
 468                 return 0;
 469
 470         if (u->meta.type != other->meta.type)
 471                 return -EINVAL;
 472
 473         if (!u->meta.instance != !other->meta.instance)
 474                 return -EINVAL;
 475
 476         if (other->meta.load_state != UNIT_STUB &&
 477             other->meta.load_state != UNIT_FAILED)
 478                 return -EEXIST;
 479
 480         if (other->meta.job)
 481                 return -EEXIST;
 482
 483         if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(other)))
 484                 return -EEXIST;
 485
 486         /* Merge names */
 487         merge_names(u, other);
 488
 489         /* Merge dependencies */
 490         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 491                 merge_dependencies(u, other, d);
 492
 493         other->meta.load_state = UNIT_MERGED;
 494         other->meta.merged_into = u;
 495
 496         /* If there is still some data attached to the other node, we
 497          * don't need it anymore, and can free it. */
 498         if (other->meta.load_state != UNIT_STUB)
 499                 if (UNIT_VTABLE(other)->done)
 500                         UNIT_VTABLE(other)->done(other);
 501
 502         unit_add_to_dbus_queue(u);
 503         unit_add_to_cleanup_queue(other);
 504
 505         return 0;
 506 }
 507
 508 int unit_merge_by_name(Unit *u, const char *name) {
 509         Unit *other;
 510         int r;
 511         char *s = NULL;
 512
 513         assert(u);
 514         assert(name);
 515
 516         if (unit_name_is_template(name)) {
 517                 if (!u->meta.instance)
 518                         return -EINVAL;
 519
 520                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 521                         return -ENOMEM;
 522
 523                 name = s;
 524         }
 525
 526         if (!(other = manager_get_unit(u->meta.manager, name)))
 527                 r = unit_add_name(u, name);
 528         else
 529                 r = unit_merge(u, other);
 530
 531         free(s);
 532         return r;
 533 }
 534
 535 Unit* unit_follow_merge(Unit *u) {
 536         assert(u);
 537
 538         while (u->meta.load_state == UNIT_MERGED)
 539                 assert_se(u = u->meta.merged_into);
 540
 541         return u;
 542 }
 543
 544 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 545         int r;
 546
 547         assert(u);
 548         assert(c);
 549
 550         if (c->std_output != EXEC_OUTPUT_KMSG &&
 551             c->std_output != EXEC_OUTPUT_SYSLOG &&
 552             c->std_error != EXEC_OUTPUT_KMSG &&
 553             c->std_error != EXEC_OUTPUT_SYSLOG)
 554                 return 0;
 555
 556         /* If syslog or kernel logging is requested, make sure our own
 557          * logging daemon is run first. */
 558
 559         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 560                 return r;
 561
 562         if (u->meta.manager->running_as == MANAGER_SYSTEM)
 563                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 564                         return r;
 565
 566         return 0;
 567 }
 568
 569 const char *unit_description(Unit *u) {
 570         assert(u);
 571
 572         if (u->meta.description)
 573                 return u->meta.description;
 574
 575         return u->meta.id;
 576 }
 577
 578 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 579         char *t;
 580         UnitDependency d;
 581         Iterator i;
 582         char *p2;
 583         const char *prefix2;
 584         CGroupBonding *b;
 585         char
 586                 timestamp1[FORMAT_TIMESTAMP_MAX],
 587                 timestamp2[FORMAT_TIMESTAMP_MAX],
 588                 timestamp3[FORMAT_TIMESTAMP_MAX],
 589                 timestamp4[FORMAT_TIMESTAMP_MAX];
 590
 591         assert(u);
 592         assert(u->meta.type >= 0);
 593
 594         if (!prefix)
 595                 prefix = "";
 596         p2 = strappend(prefix, "\t");
 597         prefix2 = p2 ? p2 : prefix;
 598
 599         fprintf(f,
 600                 "%s-> Unit %s:\n"
 601                 "%s\tDescription: %s\n"
 602                 "%s\tInstance: %s\n"
 603                 "%s\tUnit Load State: %s\n"
 604                 "%s\tUnit Active State: %s\n"
 605                 "%s\tInactive Exit Timestamp: %s\n"
 606                 "%s\tActive Enter Timestamp: %s\n"
 607                 "%s\tActive Exit Timestamp: %s\n"
 608                 "%s\tInactive Enter Timestamp: %s\n"
 609                 "%s\tGC Check Good: %s\n",
 610                 prefix, u->meta.id,
 611                 prefix, unit_description(u),
 612                 prefix, strna(u->meta.instance),
 613                 prefix, unit_load_state_to_string(u->meta.load_state),
 614                 prefix, unit_active_state_to_string(unit_active_state(u)),
 615                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 616                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 617                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 618                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 619                 prefix, yes_no(unit_check_gc(u)));
 620
 621         SET_FOREACH(t, u->meta.names, i)
 622                 fprintf(f, "%s\tName: %s\n", prefix, t);
 623
 624         if (u->meta.fragment_path)
 625                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 626
 627         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 628                 Unit *other;
 629
 630                 SET_FOREACH(other, u->meta.dependencies[d], i)
 631                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 632         }
 633
 634         if (u->meta.load_state == UNIT_LOADED) {
 635                 fprintf(f,
 636                         "%s\tRecursive Stop: %s\n"
 637                         "%s\tStopWhenUnneeded: %s\n"
 638                         "%s\tOnlyByDependency: %s\n"
 639                         "%s\tDefaultDependencies: %s\n"
 640                         "%s\tIgnoreDependencyFailure: %s\n",
 641                         prefix, yes_no(u->meta.recursive_stop),
 642                         prefix, yes_no(u->meta.stop_when_unneeded),
 643                         prefix, yes_no(u->meta.only_by_dependency),
 644                         prefix, yes_no(u->meta.default_dependencies),
 645                         prefix, yes_no(u->meta.ignore_dependency_failure));
 646
 647                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 648                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 649                                 prefix, b->controller, b->path);
 650
 651                 if (UNIT_VTABLE(u)->dump)
 652                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 653
 654         } else if (u->meta.load_state == UNIT_MERGED)
 655                 fprintf(f,
 656                         "%s\tMerged into: %s\n",
 657                         prefix, u->meta.merged_into->meta.id);
 658
 659         if (u->meta.job)
 660                 job_dump(u->meta.job, f, prefix2);
 661
 662         free(p2);
 663 }
 664
 665 /* Common implementation for multiple backends */
 666 int unit_load_fragment_and_dropin(Unit *u) {
 667         int r;
 668
 669         assert(u);
 670
 671         /* Load a .service file */
 672         if ((r = unit_load_fragment(u)) < 0)
 673                 return r;
 674
 675         if (u->meta.load_state == UNIT_STUB)
 676                 return -ENOENT;
 677
 678         /* Load drop-in directory data */
 679         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 680                 return r;
 681
 682         return 0;
 683 }
 684
 685 /* Common implementation for multiple backends */
 686 int unit_load_fragment_and_dropin_optional(Unit *u) {
 687         int r;
 688
 689         assert(u);
 690
 691         /* Same as unit_load_fragment_and_dropin(), but whether
 692          * something can be loaded or not doesn't matter. */
 693
 694         /* Load a .service file */
 695         if ((r = unit_load_fragment(u)) < 0)
 696                 return r;
 697
 698         if (u->meta.load_state == UNIT_STUB)
 699                 u->meta.load_state = UNIT_LOADED;
 700
 701         /* Load drop-in directory data */
 702         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 703                 return r;
 704
 705         return 0;
 706 }
 707
 708 /* Common implementation for multiple backends */
 709 int unit_load_nop(Unit *u) {
 710         assert(u);
 711
 712         if (u->meta.load_state == UNIT_STUB)
 713                 u->meta.load_state = UNIT_LOADED;
 714
 715         return 0;
 716 }
 717
 718 int unit_load(Unit *u) {
 719         int r;
 720
 721         assert(u);
 722
 723         if (u->meta.in_load_queue) {
 724                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 725                 u->meta.in_load_queue = false;
 726         }
 727
 728         if (u->meta.type == _UNIT_TYPE_INVALID)
 729                 return -EINVAL;
 730
 731         if (u->meta.load_state != UNIT_STUB)
 732                 return 0;
 733
 734         if (UNIT_VTABLE(u)->load)
 735                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 736                         goto fail;
 737
 738         if (u->meta.load_state == UNIT_STUB) {
 739                 r = -ENOENT;
 740                 goto fail;
 741         }
 742
 743         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 744
 745         unit_add_to_dbus_queue(unit_follow_merge(u));
 746         unit_add_to_gc_queue(u);
 747
 748         return 0;
 749
 750 fail:
 751         u->meta.load_state = UNIT_FAILED;
 752         unit_add_to_dbus_queue(u);
 753
 754         log_notice("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 755
 756         return r;
 757 }
 758
 759 /* Errors:
 760  *         -EBADR:     This unit type does not support starting.
 761  *         -EALREADY:  Unit is already started.
 762  *         -EAGAIN:    An operation is already in progress. Retry later.
 763  *         -ECANCELED: Too many requests for now.
 764  */
 765 int unit_start(Unit *u) {
 766         UnitActiveState state;
 767
 768         assert(u);
 769
 770         if (u->meta.load_state != UNIT_LOADED)
 771                 return -EINVAL;
 772
 773         /* If this is already (being) started, then this will
 774          * succeed. Note that this will even succeed if this unit is
 775          * not startable by the user. This is relied on to detect when
 776          * we need to wait for units and when waiting is finished. */
 777         state = unit_active_state(u);
 778         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 779                 return -EALREADY;
 780
 781         /* If it is stopped, but we cannot start it, then fail */
 782         if (!UNIT_VTABLE(u)->start)
 783                 return -EBADR;
 784
 785         /* We don't suppress calls to ->start() here when we are
 786          * already starting, to allow this request to be used as a
 787          * "hurry up" call, for example when the unit is in some "auto
 788          * restart" state where it waits for a holdoff timer to elapse
 789          * before it will start again. */
 790
 791         unit_add_to_dbus_queue(u);
 792
 793         unit_status_printf(u, "Starting %s...\n", unit_description(u));
 794
 795         return UNIT_VTABLE(u)->start(u);
 796 }
 797
 798 bool unit_can_start(Unit *u) {
 799         assert(u);
 800
 801         return !!UNIT_VTABLE(u)->start;
 802 }
 803
 804 /* Errors:
 805  *         -EBADR:    This unit type does not support stopping.
 806  *         -EALREADY: Unit is already stopped.
 807  *         -EAGAIN:   An operation is already in progress. Retry later.
 808  */
 809 int unit_stop(Unit *u) {
 810         UnitActiveState state;
 811
 812         assert(u);
 813
 814         state = unit_active_state(u);
 815         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(state))
 816                 return -EALREADY;
 817
 818         if (!UNIT_VTABLE(u)->stop)
 819                 return -EBADR;
 820
 821         unit_add_to_dbus_queue(u);
 822
 823         unit_status_printf(u, "Stopping %s...\n", unit_description(u));
 824
 825         return UNIT_VTABLE(u)->stop(u);
 826 }
 827
 828 /* Errors:
 829  *         -EBADR:    This unit type does not support reloading.
 830  *         -ENOEXEC:  Unit is not started.
 831  *         -EAGAIN:   An operation is already in progress. Retry later.
 832  */
 833 int unit_reload(Unit *u) {
 834         UnitActiveState state;
 835
 836         assert(u);
 837
 838         if (u->meta.load_state != UNIT_LOADED)
 839                 return -EINVAL;
 840
 841         if (!unit_can_reload(u))
 842                 return -EBADR;
 843
 844         state = unit_active_state(u);
 845         if (unit_active_state(u) == UNIT_RELOADING)
 846                 return -EALREADY;
 847
 848         if (unit_active_state(u) != UNIT_ACTIVE)
 849                 return -ENOEXEC;
 850
 851         unit_add_to_dbus_queue(u);
 852         return UNIT_VTABLE(u)->reload(u);
 853 }
 854
 855 bool unit_can_reload(Unit *u) {
 856         assert(u);
 857
 858         if (!UNIT_VTABLE(u)->reload)
 859                 return false;
 860
 861         if (!UNIT_VTABLE(u)->can_reload)
 862                 return true;
 863
 864         return UNIT_VTABLE(u)->can_reload(u);
 865 }
 866
 867 static void unit_check_uneeded(Unit *u) {
 868         Iterator i;
 869         Unit *other;
 870
 871         assert(u);
 872
 873         /* If this service shall be shut down when unneeded then do
 874          * so. */
 875
 876         if (!u->meta.stop_when_unneeded)
 877                 return;
 878
 879         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 880                 return;
 881
 882         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 883                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 884                         return;
 885
 886         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 887                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 888                         return;
 889
 890         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 891                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 892                         return;
 893
 894         log_info("Service %s is not needed anymore. Stopping.", u->meta.id);
 895
 896         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 897         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL, NULL);
 898 }
 899
 900 static void retroactively_start_dependencies(Unit *u) {
 901         Iterator i;
 902         Unit *other;
 903
 904         assert(u);
 905         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
 906
 907         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 908                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 909                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
 910
 911         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 912                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 913                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
 914
 915         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 916                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 917                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
 918
 919         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 920                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 921                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
 922
 923         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
 924                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 925                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
 926 }
 927
 928 static void retroactively_stop_dependencies(Unit *u) {
 929         Iterator i;
 930         Unit *other;
 931
 932         assert(u);
 933         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
 934
 935         if (u->meta.recursive_stop) {
 936                 /* Pull down units need us recursively if enabled */
 937                 SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 938                         if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 939                                 manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
 940         }
 941
 942         /* Garbage collect services that might not be needed anymore, if enabled */
 943         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 944                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 945                         unit_check_uneeded(other);
 946         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 947                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 948                         unit_check_uneeded(other);
 949         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 950                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 951                         unit_check_uneeded(other);
 952         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 953                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 954                         unit_check_uneeded(other);
 955         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
 956                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 957                         unit_check_uneeded(other);
 958 }
 959
 960 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
 961         dual_timestamp ts;
 962         bool unexpected;
 963
 964         assert(u);
 965         assert(os < _UNIT_ACTIVE_STATE_MAX);
 966         assert(ns < _UNIT_ACTIVE_STATE_MAX);
 967
 968         /* Note that this is called for all low-level state changes,
 969          * even if they might map to the same high-level
 970          * UnitActiveState! That means that ns == os is OK an expected
 971          * behaviour here. For example: if a mount point is remounted
 972          * this function will be called too and the utmp code below
 973          * relies on that! */
 974
 975         dual_timestamp_get(&ts);
 976
 977         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && !UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 978                 u->meta.inactive_exit_timestamp = ts;
 979         else if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 980                 u->meta.inactive_enter_timestamp = ts;
 981
 982         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
 983                 u->meta.active_enter_timestamp = ts;
 984         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
 985                 u->meta.active_exit_timestamp = ts;
 986
 987         if (ns != os && ns == UNIT_MAINTENANCE)
 988                 log_notice("Unit %s entered maintenance state.", u->meta.id);
 989
 990         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 991                 cgroup_bonding_trim_list(u->meta.cgroup_bondings, true);
 992
 993         timer_unit_notify(u, ns);
 994         path_unit_notify(u, ns);
 995
 996         if (u->meta.job) {
 997                 unexpected = false;
 998
 999                 if (u->meta.job->state == JOB_WAITING)
1000
1001                         /* So we reached a different state for this
1002                          * job. Let's see if we can run it now if it
1003                          * failed previously due to EAGAIN. */
1004                         job_add_to_run_queue(u->meta.job);
1005
1006
1007                 /* Let's check whether this state change constitutes a
1008                  * finished job, or maybe cotradicts a running job and
1009                  * hence needs to invalidate jobs. */
1010
1011                 switch (u->meta.job->type) {
1012
1013                 case JOB_START:
1014                 case JOB_VERIFY_ACTIVE:
1015
1016                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
1017                                 job_finish_and_invalidate(u->meta.job, true);
1018                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
1019                                 unexpected = true;
1020                                 job_finish_and_invalidate(u->meta.job, false);
1021                         }
1022
1023                         break;
1024
1025                 case JOB_RELOAD:
1026                 case JOB_RELOAD_OR_START:
1027
1028                         if (u->meta.job->state == JOB_RUNNING) {
1029                                 if (ns == UNIT_ACTIVE)
1030                                         job_finish_and_invalidate(u->meta.job, true);
1031                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
1032                                         unexpected = true;
1033                                         job_finish_and_invalidate(u->meta.job, false);
1034                                 }
1035                         }
1036
1037                         break;
1038
1039                 case JOB_STOP:
1040                 case JOB_RESTART:
1041                 case JOB_TRY_RESTART:
1042
1043                         if (ns == UNIT_INACTIVE || ns == UNIT_MAINTENANCE)
1044                                 job_finish_and_invalidate(u->meta.job, true);
1045                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1046                                 unexpected = true;
1047                                 job_finish_and_invalidate(u->meta.job, false);
1048                         }
1049
1050                         break;
1051
1052                 default:
1053                         assert_not_reached("Job type unknown");
1054                 }
1055
1056         } else
1057                 unexpected = true;
1058
1059         /* If this state change happened without being requested by a
1060          * job, then let's retroactively start or stop
1061          * dependencies. We skip that step when deserializing, since
1062          * we don't want to create any additional jobs just because
1063          * something is already activated. */
1064
1065         if (unexpected && u->meta.manager->n_deserializing <= 0) {
1066                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1067                         retroactively_start_dependencies(u);
1068                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1069                         retroactively_stop_dependencies(u);
1070         }
1071
1072         /* Some names are special */
1073         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1074                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1075                         /* The bus just might have become available,
1076                          * hence try to connect to it, if we aren't
1077                          * yet connected. */
1078                         bus_init(u->meta.manager);
1079                 }
1080
1081                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1082                         /* The syslog daemon just might have become
1083                          * available, hence try to connect to it, if
1084                          * we aren't yet connected. */
1085                         log_open();
1086
1087                 if (u->meta.type == UNIT_MOUNT)
1088                         /* Another directory became available, let's
1089                          * check if that is enough to write our utmp
1090                          * entry. */
1091                         manager_write_utmp_reboot(u->meta.manager);
1092
1093                 if (u->meta.type == UNIT_TARGET)
1094                         /* A target got activated, maybe this is a runlevel? */
1095                         manager_write_utmp_runlevel(u->meta.manager, u);
1096
1097         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1098
1099                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1100                         /* The syslog daemon might just have
1101                          * terminated, hence try to disconnect from
1102                          * it. */
1103                         log_close_syslog();
1104
1105                 /* We don't care about D-Bus here, since we'll get an
1106                  * asynchronous notification for it anyway. */
1107         }
1108
1109         /* Maybe we finished startup and are now ready for being
1110          * stopped because unneeded? */
1111         unit_check_uneeded(u);
1112
1113         unit_add_to_dbus_queue(u);
1114         unit_add_to_gc_queue(u);
1115 }
1116
1117 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1118         struct epoll_event ev;
1119
1120         assert(u);
1121         assert(fd >= 0);
1122         assert(w);
1123         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1124
1125         zero(ev);
1126         ev.data.ptr = w;
1127         ev.events = events;
1128
1129         if (epoll_ctl(u->meta.manager->epoll_fd,
1130                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1131                       fd,
1132                       &ev) < 0)
1133                 return -errno;
1134
1135         w->fd = fd;
1136         w->type = WATCH_FD;
1137         w->data.unit = u;
1138
1139         return 0;
1140 }
1141
1142 void unit_unwatch_fd(Unit *u, Watch *w) {
1143         assert(u);
1144         assert(w);
1145
1146         if (w->type == WATCH_INVALID)
1147                 return;
1148
1149         assert(w->type == WATCH_FD);
1150         assert(w->data.unit == u);
1151         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1152
1153         w->fd = -1;
1154         w->type = WATCH_INVALID;
1155         w->data.unit = NULL;
1156 }
1157
1158 int unit_watch_pid(Unit *u, pid_t pid) {
1159         assert(u);
1160         assert(pid >= 1);
1161
1162         /* Watch a specific PID. We only support one unit watching
1163          * each PID for now. */
1164
1165         return hashmap_put(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1166 }
1167
1168 void unit_unwatch_pid(Unit *u, pid_t pid) {
1169         assert(u);
1170         assert(pid >= 1);
1171
1172         hashmap_remove_value(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1173 }
1174
1175 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1176         struct itimerspec its;
1177         int flags, fd;
1178         bool ours;
1179
1180         assert(u);
1181         assert(w);
1182         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1183
1184         /* This will try to reuse the old timer if there is one */
1185
1186         if (w->type == WATCH_TIMER) {
1187                 ours = false;
1188                 fd = w->fd;
1189         } else {
1190                 ours = true;
1191                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1192                         return -errno;
1193         }
1194
1195         zero(its);
1196
1197         if (delay <= 0) {
1198                 /* Set absolute time in the past, but not 0, since we
1199                  * don't want to disarm the timer */
1200                 its.it_value.tv_sec = 0;
1201                 its.it_value.tv_nsec = 1;
1202
1203                 flags = TFD_TIMER_ABSTIME;
1204         } else {
1205                 timespec_store(&its.it_value, delay);
1206                 flags = 0;
1207         }
1208
1209         /* This will also flush the elapse counter */
1210         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1211                 goto fail;
1212
1213         if (w->type == WATCH_INVALID) {
1214                 struct epoll_event ev;
1215
1216                 zero(ev);
1217                 ev.data.ptr = w;
1218                 ev.events = EPOLLIN;
1219
1220                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1221                         goto fail;
1222         }
1223
1224         w->fd = fd;
1225         w->type = WATCH_TIMER;
1226         w->data.unit = u;
1227
1228         return 0;
1229
1230 fail:
1231         if (ours)
1232                 close_nointr_nofail(fd);
1233
1234         return -errno;
1235 }
1236
1237 void unit_unwatch_timer(Unit *u, Watch *w) {
1238         assert(u);
1239         assert(w);
1240
1241         if (w->type == WATCH_INVALID)
1242                 return;
1243
1244         assert(w->type == WATCH_TIMER && w->data.unit == u);
1245
1246         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1247         close_nointr_nofail(w->fd);
1248
1249         w->fd = -1;
1250         w->type = WATCH_INVALID;
1251         w->data.unit = NULL;
1252 }
1253
1254 bool unit_job_is_applicable(Unit *u, JobType j) {
1255         assert(u);
1256         assert(j >= 0 && j < _JOB_TYPE_MAX);
1257
1258         switch (j) {
1259
1260         case JOB_VERIFY_ACTIVE:
1261         case JOB_START:
1262                 return true;
1263
1264         case JOB_STOP:
1265         case JOB_RESTART:
1266         case JOB_TRY_RESTART:
1267                 return unit_can_start(u);
1268
1269         case JOB_RELOAD:
1270                 return unit_can_reload(u);
1271
1272         case JOB_RELOAD_OR_START:
1273                 return unit_can_reload(u) && unit_can_start(u);
1274
1275         default:
1276                 assert_not_reached("Invalid job type");
1277         }
1278 }
1279
1280 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1281
1282         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1283                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1284                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1285                 [UNIT_WANTS] = UNIT_WANTED_BY,
1286                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1287                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1288                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1289                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1290                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1291                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1292                 [UNIT_BEFORE] = UNIT_AFTER,
1293                 [UNIT_AFTER] = UNIT_BEFORE,
1294                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1295                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1296         };
1297         int r, q = 0, v = 0, w = 0;
1298
1299         assert(u);
1300         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1301         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1302         assert(other);
1303
1304         /* We won't allow dependencies on ourselves. We will not
1305          * consider them an error however. */
1306         if (u == other)
1307                 return 0;
1308
1309         if (UNIT_VTABLE(u)->no_requires &&
1310             (d == UNIT_REQUIRES ||
1311              d == UNIT_REQUIRES_OVERRIDABLE ||
1312              d == UNIT_REQUISITE ||
1313              d == UNIT_REQUISITE_OVERRIDABLE)) {
1314                     return -EINVAL;
1315         }
1316
1317         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1318             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1319                 return r;
1320
1321         if (add_reference)
1322                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1323                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1324                         return r;
1325
1326         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1327                 return q;
1328
1329         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1330                 r = v;
1331                 goto fail;
1332         }
1333
1334         if (add_reference) {
1335                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1336                         r = w;
1337                         goto fail;
1338                 }
1339
1340                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1341                         goto fail;
1342         }
1343
1344         unit_add_to_dbus_queue(u);
1345         return 0;
1346
1347 fail:
1348         if (q > 0)
1349                 set_remove(u->meta.dependencies[d], other);
1350
1351         if (v > 0)
1352                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1353
1354         if (w > 0)
1355                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1356
1357         return r;
1358 }
1359
1360 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference) {
1361         int r;
1362
1363         assert(u);
1364
1365         if ((r = unit_add_dependency(u, d, other, add_reference)) < 0)
1366                 return r;
1367
1368         if ((r = unit_add_dependency(u, e, other, add_reference)) < 0)
1369                 return r;
1370
1371         return 0;
1372 }
1373
1374 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1375         char *s;
1376
1377         assert(u);
1378         assert(name || path);
1379
1380         if (!name)
1381                 name = file_name_from_path(path);
1382
1383         if (!unit_name_is_template(name)) {
1384                 *p = NULL;
1385                 return name;
1386         }
1387
1388         if (u->meta.instance)
1389                 s = unit_name_replace_instance(name, u->meta.instance);
1390         else {
1391                 char *i;
1392
1393                 if (!(i = unit_name_to_prefix(u->meta.id)))
1394                         return NULL;
1395
1396                 s = unit_name_replace_instance(name, i);
1397                 free(i);
1398         }
1399
1400         if (!s)
1401                 return NULL;
1402
1403         *p = s;
1404         return s;
1405 }
1406
1407 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1408         Unit *other;
1409         int r;
1410         char *s;
1411
1412         assert(u);
1413         assert(name || path);
1414
1415         if (!(name = resolve_template(u, name, path, &s)))
1416                 return -ENOMEM;
1417
1418         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1419                 goto finish;
1420
1421         r = unit_add_dependency(u, d, other, add_reference);
1422
1423 finish:
1424         free(s);
1425         return r;
1426 }
1427
1428 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1429         Unit *other;
1430         int r;
1431         char *s;
1432
1433         assert(u);
1434         assert(name || path);
1435
1436         if (!(name = resolve_template(u, name, path, &s)))
1437                 return -ENOMEM;
1438
1439         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1440                 goto finish;
1441
1442         r = unit_add_two_dependencies(u, d, e, other, add_reference);
1443
1444 finish:
1445         free(s);
1446         return r;
1447 }
1448
1449 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1450         Unit *other;
1451         int r;
1452         char *s;
1453
1454         assert(u);
1455         assert(name || path);
1456
1457         if (!(name = resolve_template(u, name, path, &s)))
1458                 return -ENOMEM;
1459
1460         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1461                 goto finish;
1462
1463         r = unit_add_dependency(other, d, u, add_reference);
1464
1465 finish:
1466         free(s);
1467         return r;
1468 }
1469
1470 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1471         Unit *other;
1472         int r;
1473         char *s;
1474
1475         assert(u);
1476         assert(name || path);
1477
1478         if (!(name = resolve_template(u, name, path, &s)))
1479                 return -ENOMEM;
1480
1481         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1482                 goto finish;
1483
1484         if ((r = unit_add_two_dependencies(other, d, e, u, add_reference)) < 0)
1485                 goto finish;
1486
1487 finish:
1488         free(s);
1489         return r;
1490 }
1491
1492 int set_unit_path(const char *p) {
1493         char *cwd, *c;
1494         int r;
1495
1496         /* This is mostly for debug purposes */
1497
1498         if (path_is_absolute(p)) {
1499                 if (!(c = strdup(p)))
1500                         return -ENOMEM;
1501         } else {
1502                 if (!(cwd = get_current_dir_name()))
1503                         return -errno;
1504
1505                 r = asprintf(&c, "%s/%s", cwd, p);
1506                 free(cwd);
1507
1508                 if (r < 0)
1509                         return -ENOMEM;
1510         }
1511
1512         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1513                 r = -errno;
1514                 free(c);
1515                 return r;
1516         }
1517
1518         return 0;
1519 }
1520
1521 char *unit_dbus_path(Unit *u) {
1522         char *p, *e;
1523
1524         assert(u);
1525
1526         if (!(e = bus_path_escape(u->meta.id)))
1527                 return NULL;
1528
1529         p = strappend("/org/freedesktop/systemd1/unit/", e);
1530         free(e);
1531
1532         return p;
1533 }
1534
1535 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1536         CGroupBonding *l;
1537         int r;
1538
1539         assert(u);
1540         assert(b);
1541
1542         assert(b->path);
1543
1544         if (!b->controller)
1545                 if (!(b->controller = strdup(SYSTEMD_CGROUP_CONTROLLER)))
1546                         return -ENOMEM;
1547
1548         /* Ensure this hasn't been added yet */
1549         assert(!b->unit);
1550
1551         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1552         LIST_PREPEND(CGroupBonding, by_path, l, b);
1553
1554         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1555                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1556                 return r;
1557         }
1558
1559         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1560         b->unit = u;
1561
1562         return 0;
1563 }
1564
1565 static char *default_cgroup_path(Unit *u) {
1566         char *p;
1567         int r;
1568
1569         assert(u);
1570
1571         if (u->meta.instance) {
1572                 char *t;
1573
1574                 if (!(t = unit_name_template(u->meta.id)))
1575                         return NULL;
1576
1577                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1578                 free(t);
1579         } else
1580                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1581
1582         return r < 0 ? NULL : p;
1583 }
1584
1585 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1586         char *controller = NULL, *path = NULL;
1587         CGroupBonding *b = NULL;
1588         int r;
1589
1590         assert(u);
1591         assert(name);
1592
1593         if ((r = cg_split_spec(name, &controller, &path)) < 0)
1594                 return r;
1595
1596         if (!path)
1597                 path = default_cgroup_path(u);
1598
1599         if (!controller)
1600                 controller = strdup(SYSTEMD_CGROUP_CONTROLLER);
1601
1602         if (!path || !controller) {
1603                 free(path);
1604                 free(controller);
1605
1606                 return -ENOMEM;
1607         }
1608
1609         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1610                 r = -EEXIST;
1611                 goto fail;
1612         }
1613
1614         if (!(b = new0(CGroupBonding, 1))) {
1615                 r = -ENOMEM;
1616                 goto fail;
1617         }
1618
1619         b->controller = controller;
1620         b->path = path;
1621         b->only_us = false;
1622         b->clean_up = false;
1623
1624         if ((r = unit_add_cgroup(u, b)) < 0)
1625                 goto fail;
1626
1627         return 0;
1628
1629 fail:
1630         free(path);
1631         free(controller);
1632         free(b);
1633
1634         return r;
1635 }
1636
1637 int unit_add_default_cgroup(Unit *u) {
1638         CGroupBonding *b;
1639         int r = -ENOMEM;
1640
1641         assert(u);
1642
1643         /* Adds in the default cgroup data, if it wasn't specified yet */
1644
1645         if (unit_get_default_cgroup(u))
1646                 return 0;
1647
1648         if (!(b = new0(CGroupBonding, 1)))
1649                 return -ENOMEM;
1650
1651         if (!(b->path = default_cgroup_path(u)))
1652                 goto fail;
1653
1654         b->clean_up = true;
1655         b->only_us = true;
1656
1657         if ((r = unit_add_cgroup(u, b)) < 0)
1658                 goto fail;
1659
1660         return 0;
1661
1662 fail:
1663         free(b->path);
1664         free(b->controller);
1665         free(b);
1666
1667         return r;
1668 }
1669
1670 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1671         assert(u);
1672
1673         return cgroup_bonding_find_list(u->meta.cgroup_bondings, SYSTEMD_CGROUP_CONTROLLER);
1674 }
1675
1676 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1677         char *t;
1678         int r;
1679
1680         assert(u);
1681         assert(type);
1682         assert(_found);
1683
1684         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1685                 return -ENOMEM;
1686
1687         assert(!unit_has_name(u, t));
1688
1689         r = manager_load_unit(u->meta.manager, t, NULL, NULL, _found);
1690         free(t);
1691
1692         assert(r < 0 || *_found != u);
1693
1694         return r;
1695 }
1696
1697 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1698         Unit *found;
1699         char *t;
1700
1701         assert(u);
1702         assert(type);
1703         assert(_found);
1704
1705         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1706                 return -ENOMEM;
1707
1708         assert(!unit_has_name(u, t));
1709
1710         found = manager_get_unit(u->meta.manager, t);
1711         free(t);
1712
1713         if (!found)
1714                 return -ENOENT;
1715
1716         *_found = found;
1717         return 0;
1718 }
1719
1720 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1721         Unit *u = userdata;
1722         assert(u);
1723
1724         return unit_name_to_prefix_and_instance(u->meta.id);
1725 }
1726
1727 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1728         Unit *u = userdata;
1729         assert(u);
1730
1731         return unit_name_to_prefix(u->meta.id);
1732 }
1733
1734 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1735         Unit *u = userdata;
1736         char *p, *r;
1737
1738         assert(u);
1739
1740         if (!(p = unit_name_to_prefix(u->meta.id)))
1741                 return NULL;
1742
1743         r = unit_name_unescape(p);
1744         free(p);
1745
1746         return r;
1747 }
1748
1749 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1750         Unit *u = userdata;
1751         assert(u);
1752
1753         if (u->meta.instance)
1754                 return unit_name_unescape(u->meta.instance);
1755
1756         return strdup("");
1757 }
1758
1759 char *unit_name_printf(Unit *u, const char* format) {
1760
1761         /*
1762          * This will use the passed string as format string and
1763          * replace the following specifiers:
1764          *
1765          * %n: the full id of the unit                 (foo@bar.waldo)
1766          * %N: the id of the unit without the suffix   (foo@bar)
1767          * %p: the prefix                              (foo)
1768          * %i: the instance                            (bar)
1769          */
1770
1771         const Specifier table[] = {
1772                 { 'n', specifier_string,              u->meta.id },
1773                 { 'N', specifier_prefix_and_instance, NULL },
1774                 { 'p', specifier_prefix,              NULL },
1775                 { 'i', specifier_string,              u->meta.instance },
1776                 { 0, NULL, NULL }
1777         };
1778
1779         assert(u);
1780         assert(format);
1781
1782         return specifier_printf(format, table, u);
1783 }
1784
1785 char *unit_full_printf(Unit *u, const char *format) {
1786
1787         /* This is similar to unit_name_printf() but also supports
1788          * unescaping */
1789
1790         const Specifier table[] = {
1791                 { 'n', specifier_string,              u->meta.id },
1792                 { 'N', specifier_prefix_and_instance, NULL },
1793                 { 'p', specifier_prefix,              NULL },
1794                 { 'P', specifier_prefix_unescaped,    NULL },
1795                 { 'i', specifier_string,              u->meta.instance },
1796                 { 'I', specifier_instance_unescaped,  NULL },
1797                 { 0, NULL, NULL }
1798         };
1799
1800         assert(u);
1801         assert(format);
1802
1803         return specifier_printf(format, table, u);
1804 }
1805
1806 char **unit_full_printf_strv(Unit *u, char **l) {
1807         size_t n;
1808         char **r, **i, **j;
1809
1810         /* Applies unit_full_printf to every entry in l */
1811
1812         assert(u);
1813
1814         n = strv_length(l);
1815         if (!(r = new(char*, n+1)))
1816                 return NULL;
1817
1818         for (i = l, j = r; *i; i++, j++)
1819                 if (!(*j = unit_full_printf(u, *i)))
1820                         goto fail;
1821
1822         *j = NULL;
1823         return r;
1824
1825 fail:
1826         j--;
1827         while (j >= r)
1828                 free(*j);
1829
1830         free(r);
1831
1832         return NULL;
1833 }
1834
1835 int unit_watch_bus_name(Unit *u, const char *name) {
1836         assert(u);
1837         assert(name);
1838
1839         /* Watch a specific name on the bus. We only support one unit
1840          * watching each name for now. */
1841
1842         return hashmap_put(u->meta.manager->watch_bus, name, u);
1843 }
1844
1845 void unit_unwatch_bus_name(Unit *u, const char *name) {
1846         assert(u);
1847         assert(name);
1848
1849         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1850 }
1851
1852 bool unit_can_serialize(Unit *u) {
1853         assert(u);
1854
1855         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1856 }
1857
1858 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1859         int r;
1860
1861         assert(u);
1862         assert(f);
1863         assert(fds);
1864
1865         if (!unit_can_serialize(u))
1866                 return 0;
1867
1868         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1869                 return r;
1870
1871         if (u->meta.job)
1872                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1873
1874         /* End marker */
1875         fputc('\n', f);
1876         return 0;
1877 }
1878
1879 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1880         va_list ap;
1881
1882         assert(u);
1883         assert(f);
1884         assert(key);
1885         assert(format);
1886
1887         fputs(key, f);
1888         fputc('=', f);
1889
1890         va_start(ap, format);
1891         vfprintf(f, format, ap);
1892         va_end(ap);
1893
1894         fputc('\n', f);
1895 }
1896
1897 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1898         assert(u);
1899         assert(f);
1900         assert(key);
1901         assert(value);
1902
1903         fprintf(f, "%s=%s\n", key, value);
1904 }
1905
1906 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1907         int r;
1908
1909         assert(u);
1910         assert(f);
1911         assert(fds);
1912
1913         if (!unit_can_serialize(u))
1914                 return 0;
1915
1916         for (;;) {
1917                 char line[1024], *l, *v;
1918                 size_t k;
1919
1920                 if (!fgets(line, sizeof(line), f)) {
1921                         if (feof(f))
1922                                 return 0;
1923                         return -errno;
1924                 }
1925
1926                 l = strstrip(line);
1927
1928                 /* End marker */
1929                 if (l[0] == 0)
1930                         return 0;
1931
1932                 k = strcspn(l, "=");
1933
1934                 if (l[k] == '=') {
1935                         l[k] = 0;
1936                         v = l+k+1;
1937                 } else
1938                         v = l+k;
1939
1940                 if (streq(l, "job")) {
1941                         JobType type;
1942
1943                         if ((type = job_type_from_string(v)) < 0)
1944                                 log_debug("Failed to parse job type value %s", v);
1945                         else
1946                                 u->meta.deserialized_job = type;
1947
1948                         continue;
1949                 }
1950
1951                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1952                         return r;
1953         }
1954 }
1955
1956 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1957         Unit *device;
1958         char *e;
1959         int r;
1960
1961         assert(u);
1962
1963         if (!what)
1964                 return 0;
1965
1966         /* Adds in links to the device node that this unit is based on */
1967
1968         if (!is_device_path(what))
1969                 return 0;
1970
1971         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1972                 return -ENOMEM;
1973
1974         r = manager_load_unit(u->meta.manager, e, NULL, NULL, &device);
1975         free(e);
1976
1977         if (r < 0)
1978                 return r;
1979
1980         if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_REQUIRES, device, true)) < 0)
1981                 return r;
1982
1983         if (wants)
1984                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1985                         return r;
1986
1987         return 0;
1988 }
1989
1990 int unit_coldplug(Unit *u) {
1991         int r;
1992
1993         assert(u);
1994
1995         if (UNIT_VTABLE(u)->coldplug)
1996                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
1997                         return r;
1998
1999         if (u->meta.deserialized_job >= 0) {
2000                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL, NULL)) < 0)
2001                         return r;
2002
2003                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
2004         }
2005
2006         return 0;
2007 }
2008
2009 void unit_status_printf(Unit *u, const char *format, ...) {
2010         va_list ap;
2011
2012         assert(u);
2013         assert(format);
2014
2015         if (!UNIT_VTABLE(u)->show_status)
2016                 return;
2017
2018         if (u->meta.manager->running_as != MANAGER_SYSTEM)
2019                 return;
2020
2021         if (!u->meta.manager->show_status)
2022                 return;
2023
2024         if (!manager_is_booting_or_shutting_down(u->meta.manager))
2025                 return;
2026
2027         va_start(ap, format);
2028         status_vprintf(format, ap);
2029         va_end(ap);
2030 }
2031
2032 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
2033         [UNIT_SERVICE] = "service",
2034         [UNIT_TIMER] = "timer",
2035         [UNIT_SOCKET] = "socket",
2036         [UNIT_TARGET] = "target",
2037         [UNIT_DEVICE] = "device",
2038         [UNIT_MOUNT] = "mount",
2039         [UNIT_AUTOMOUNT] = "automount",
2040         [UNIT_SNAPSHOT] = "snapshot",
2041         [UNIT_SWAP] = "swap"
2042 };
2043
2044 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
2045
2046 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
2047         [UNIT_STUB] = "stub",
2048         [UNIT_LOADED] = "loaded",
2049         [UNIT_FAILED] = "failed",
2050         [UNIT_MERGED] = "merged"
2051 };
2052
2053 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
2054
2055 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
2056         [UNIT_ACTIVE] = "active",
2057         [UNIT_RELOADING] = "reloading",
2058         [UNIT_INACTIVE] = "inactive",
2059         [UNIT_MAINTENANCE] = "maintenance",
2060         [UNIT_ACTIVATING] = "activating",
2061         [UNIT_DEACTIVATING] = "deactivating"
2062 };
2063
2064 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
2065
2066 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
2067         [UNIT_REQUIRES] = "Requires",
2068         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
2069         [UNIT_WANTS] = "Wants",
2070         [UNIT_REQUISITE] = "Requisite",
2071         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
2072         [UNIT_REQUIRED_BY] = "RequiredBy",
2073         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
2074         [UNIT_WANTED_BY] = "WantedBy",
2075         [UNIT_CONFLICTS] = "Conflicts",
2076         [UNIT_BEFORE] = "Before",
2077         [UNIT_AFTER] = "After",
2078         [UNIT_REFERENCES] = "References",
2079         [UNIT_REFERENCED_BY] = "ReferencedBy"
2080 };
2081
2082 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
2083
2084 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2085         [KILL_CONTROL_GROUP] = "control-group",
2086         [KILL_PROCESS_GROUP] = "process-group",
2087         [KILL_PROCESS] = "process",
2088         [KILL_NONE] = "none"
2089 };
2090
2091 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);