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 #include <sys/stat.h>
  31
  32 #include "set.h"
  33 #include "unit.h"
  34 #include "macro.h"
  35 #include "strv.h"
  36 #include "load-fragment.h"
  37 #include "load-dropin.h"
  38 #include "log.h"
  39 #include "unit-name.h"
  40 #include "specifier.h"
  41 #include "dbus-unit.h"
  42 #include "special.h"
  43 #include "cgroup-util.h"
  44
  45 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  46         [UNIT_SERVICE] = &service_vtable,
  47         [UNIT_TIMER] = &timer_vtable,
  48         [UNIT_SOCKET] = &socket_vtable,
  49         [UNIT_TARGET] = &target_vtable,
  50         [UNIT_DEVICE] = &device_vtable,
  51         [UNIT_MOUNT] = &mount_vtable,
  52         [UNIT_AUTOMOUNT] = &automount_vtable,
  53         [UNIT_SNAPSHOT] = &snapshot_vtable,
  54         [UNIT_SWAP] = &swap_vtable,
  55         [UNIT_PATH] = &path_vtable
  56 };
  57
  58 Unit *unit_new(Manager *m) {
  59         Unit *u;
  60
  61         assert(m);
  62
  63         if (!(u = new0(Unit, 1)))
  64                 return NULL;
  65
  66         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  67                 free(u);
  68                 return NULL;
  69         }
  70
  71         u->meta.manager = m;
  72         u->meta.type = _UNIT_TYPE_INVALID;
  73         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  74         u->meta.default_dependencies = true;
  75
  76         return u;
  77 }
  78
  79 bool unit_has_name(Unit *u, const char *name) {
  80         assert(u);
  81         assert(name);
  82
  83         return !!set_get(u->meta.names, (char*) name);
  84 }
  85
  86 int unit_add_name(Unit *u, const char *text) {
  87         UnitType t;
  88         char *s, *i = NULL;
  89         int r;
  90
  91         assert(u);
  92         assert(text);
  93
  94         if (unit_name_is_template(text)) {
  95                 if (!u->meta.instance)
  96                         return -EINVAL;
  97
  98                 s = unit_name_replace_instance(text, u->meta.instance);
  99         } else
 100                 s = strdup(text);
 101
 102         if (!s)
 103                 return -ENOMEM;
 104
 105         if (!unit_name_is_valid(s)) {
 106                 r = -EINVAL;
 107                 goto fail;
 108         }
 109
 110         assert_se((t = unit_name_to_type(s)) >= 0);
 111
 112         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 113                 r = -EINVAL;
 114                 goto fail;
 115         }
 116
 117         if ((r = unit_name_to_instance(s, &i)) < 0)
 118                 goto fail;
 119
 120         if (i && unit_vtable[t]->no_instances)
 121                 goto fail;
 122
 123         /* Ensure that this unit is either instanced or not instanced,
 124          * but not both. */
 125         if (u->meta.type != _UNIT_TYPE_INVALID && !u->meta.instance != !i) {
 126                 r = -EINVAL;
 127                 goto fail;
 128         }
 129
 130         if (unit_vtable[t]->no_alias &&
 131             !set_isempty(u->meta.names) &&
 132             !set_get(u->meta.names, s)) {
 133                 r = -EEXIST;
 134                 goto fail;
 135         }
 136
 137         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 138                 r = -E2BIG;
 139                 goto fail;
 140         }
 141
 142         if ((r = set_put(u->meta.names, s)) < 0) {
 143                 if (r == -EEXIST)
 144                         r = 0;
 145                 goto fail;
 146         }
 147
 148         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 149                 set_remove(u->meta.names, s);
 150                 goto fail;
 151         }
 152
 153         if (u->meta.type == _UNIT_TYPE_INVALID) {
 154
 155                 u->meta.type = t;
 156                 u->meta.id = s;
 157                 u->meta.instance = i;
 158
 159                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 160
 161                 if (UNIT_VTABLE(u)->init)
 162                         UNIT_VTABLE(u)->init(u);
 163         } else
 164                 free(i);
 165
 166         unit_add_to_dbus_queue(u);
 167         return 0;
 168
 169 fail:
 170         free(s);
 171         free(i);
 172
 173         return r;
 174 }
 175
 176 int unit_choose_id(Unit *u, const char *name) {
 177         char *s, *t = NULL, *i;
 178         int r;
 179
 180         assert(u);
 181         assert(name);
 182
 183         if (unit_name_is_template(name)) {
 184
 185                 if (!u->meta.instance)
 186                         return -EINVAL;
 187
 188                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 189                         return -ENOMEM;
 190
 191                 name = t;
 192         }
 193
 194         /* Selects one of the names of this unit as the id */
 195         s = set_get(u->meta.names, (char*) name);
 196         free(t);
 197
 198         if (!s)
 199                 return -ENOENT;
 200
 201         if ((r = unit_name_to_instance(s, &i)) < 0)
 202                 return r;
 203
 204         u->meta.id = s;
 205
 206         free(u->meta.instance);
 207         u->meta.instance = i;
 208
 209         unit_add_to_dbus_queue(u);
 210
 211         return 0;
 212 }
 213
 214 int unit_set_description(Unit *u, const char *description) {
 215         char *s;
 216
 217         assert(u);
 218
 219         if (!(s = strdup(description)))
 220                 return -ENOMEM;
 221
 222         free(u->meta.description);
 223         u->meta.description = s;
 224
 225         unit_add_to_dbus_queue(u);
 226         return 0;
 227 }
 228
 229 bool unit_check_gc(Unit *u) {
 230         assert(u);
 231
 232         if (u->meta.load_state == UNIT_STUB)
 233                 return true;
 234
 235         if (UNIT_VTABLE(u)->no_gc)
 236                 return true;
 237
 238         if (u->meta.job)
 239                 return true;
 240
 241         if (unit_active_state(u) != UNIT_INACTIVE)
 242                 return true;
 243
 244         if (UNIT_VTABLE(u)->check_gc)
 245                 if (UNIT_VTABLE(u)->check_gc(u))
 246                         return true;
 247
 248         return false;
 249 }
 250
 251 void unit_add_to_load_queue(Unit *u) {
 252         assert(u);
 253         assert(u->meta.type != _UNIT_TYPE_INVALID);
 254
 255         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 256                 return;
 257
 258         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 259         u->meta.in_load_queue = true;
 260 }
 261
 262 void unit_add_to_cleanup_queue(Unit *u) {
 263         assert(u);
 264
 265         if (u->meta.in_cleanup_queue)
 266                 return;
 267
 268         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 269         u->meta.in_cleanup_queue = true;
 270 }
 271
 272 void unit_add_to_gc_queue(Unit *u) {
 273         assert(u);
 274
 275         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 276                 return;
 277
 278         if (unit_check_gc(u))
 279                 return;
 280
 281         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 282         u->meta.in_gc_queue = true;
 283
 284         u->meta.manager->n_in_gc_queue ++;
 285
 286         if (u->meta.manager->gc_queue_timestamp <= 0)
 287                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 288 }
 289
 290 void unit_add_to_dbus_queue(Unit *u) {
 291         assert(u);
 292         assert(u->meta.type != _UNIT_TYPE_INVALID);
 293
 294         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 295                 return;
 296
 297         /* Shortcut things if nobody cares */
 298         if (!bus_has_subscriber(u->meta.manager)) {
 299                 u->meta.sent_dbus_new_signal = true;
 300                 return;
 301         }
 302
 303         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 304         u->meta.in_dbus_queue = true;
 305 }
 306
 307 static void bidi_set_free(Unit *u, Set *s) {
 308         Iterator i;
 309         Unit *other;
 310
 311         assert(u);
 312
 313         /* Frees the set and makes sure we are dropped from the
 314          * inverse pointers */
 315
 316         SET_FOREACH(other, s, i) {
 317                 UnitDependency d;
 318
 319                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 320                         set_remove(other->meta.dependencies[d], u);
 321
 322                 unit_add_to_gc_queue(other);
 323         }
 324
 325         set_free(s);
 326 }
 327
 328 void unit_free(Unit *u) {
 329         UnitDependency d;
 330         Iterator i;
 331         char *t;
 332
 333         assert(u);
 334
 335         bus_unit_send_removed_signal(u);
 336
 337         if (u->meta.load_state != UNIT_STUB)
 338                 if (UNIT_VTABLE(u)->done)
 339                         UNIT_VTABLE(u)->done(u);
 340
 341         SET_FOREACH(t, u->meta.names, i)
 342                 hashmap_remove_value(u->meta.manager->units, t, u);
 343
 344         if (u->meta.job)
 345                 job_free(u->meta.job);
 346
 347         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 348                 bidi_set_free(u, u->meta.dependencies[d]);
 349
 350         if (u->meta.type != _UNIT_TYPE_INVALID)
 351                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 352
 353         if (u->meta.in_load_queue)
 354                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 355
 356         if (u->meta.in_dbus_queue)
 357                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 358
 359         if (u->meta.in_cleanup_queue)
 360                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 361
 362         if (u->meta.in_gc_queue) {
 363                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 364                 u->meta.manager->n_in_gc_queue--;
 365         }
 366
 367         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 368
 369         free(u->meta.description);
 370         free(u->meta.fragment_path);
 371
 372         set_free_free(u->meta.names);
 373
 374         free(u->meta.instance);
 375
 376         free(u);
 377 }
 378
 379 UnitActiveState unit_active_state(Unit *u) {
 380         assert(u);
 381
 382         if (u->meta.load_state == UNIT_MERGED)
 383                 return unit_active_state(unit_follow_merge(u));
 384
 385         /* After a reload it might happen that a unit is not correctly
 386          * loaded but still has a process around. That's why we won't
 387          * shortcut failed loading to UNIT_INACTIVE_MAINTENANCE. */
 388
 389         return UNIT_VTABLE(u)->active_state(u);
 390 }
 391
 392 const char* unit_sub_state_to_string(Unit *u) {
 393         assert(u);
 394
 395         return UNIT_VTABLE(u)->sub_state_to_string(u);
 396 }
 397
 398 static void complete_move(Set **s, Set **other) {
 399         assert(s);
 400         assert(other);
 401
 402         if (!*other)
 403                 return;
 404
 405         if (*s)
 406                 set_move(*s, *other);
 407         else {
 408                 *s = *other;
 409                 *other = NULL;
 410         }
 411 }
 412
 413 static void merge_names(Unit *u, Unit *other) {
 414         char *t;
 415         Iterator i;
 416
 417         assert(u);
 418         assert(other);
 419
 420         complete_move(&u->meta.names, &other->meta.names);
 421
 422         set_free_free(other->meta.names);
 423         other->meta.names = NULL;
 424         other->meta.id = NULL;
 425
 426         SET_FOREACH(t, u->meta.names, i)
 427                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 428 }
 429
 430 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 431         Iterator i;
 432         Unit *back;
 433         int r;
 434
 435         assert(u);
 436         assert(other);
 437         assert(d < _UNIT_DEPENDENCY_MAX);
 438
 439         SET_FOREACH(back, other->meta.dependencies[d], i) {
 440                 UnitDependency k;
 441
 442                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 443                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 444
 445                                 if (r == -EEXIST)
 446                                         set_remove(back->meta.dependencies[k], other);
 447                                 else
 448                                         assert(r == -ENOENT);
 449                         }
 450         }
 451
 452         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 453
 454         set_free(other->meta.dependencies[d]);
 455         other->meta.dependencies[d] = NULL;
 456 }
 457
 458 int unit_merge(Unit *u, Unit *other) {
 459         UnitDependency d;
 460
 461         assert(u);
 462         assert(other);
 463         assert(u->meta.manager == other->meta.manager);
 464         assert(u->meta.type != _UNIT_TYPE_INVALID);
 465
 466         other = unit_follow_merge(other);
 467
 468         if (other == u)
 469                 return 0;
 470
 471         if (u->meta.type != other->meta.type)
 472                 return -EINVAL;
 473
 474         if (!u->meta.instance != !other->meta.instance)
 475                 return -EINVAL;
 476
 477         if (other->meta.load_state != UNIT_STUB &&
 478             other->meta.load_state != UNIT_FAILED)
 479                 return -EEXIST;
 480
 481         if (other->meta.job)
 482                 return -EEXIST;
 483
 484         if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(other)))
 485                 return -EEXIST;
 486
 487         /* Merge names */
 488         merge_names(u, other);
 489
 490         /* Merge dependencies */
 491         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 492                 merge_dependencies(u, other, d);
 493
 494         other->meta.load_state = UNIT_MERGED;
 495         other->meta.merged_into = u;
 496
 497         /* If there is still some data attached to the other node, we
 498          * don't need it anymore, and can free it. */
 499         if (other->meta.load_state != UNIT_STUB)
 500                 if (UNIT_VTABLE(other)->done)
 501                         UNIT_VTABLE(other)->done(other);
 502
 503         unit_add_to_dbus_queue(u);
 504         unit_add_to_cleanup_queue(other);
 505
 506         return 0;
 507 }
 508
 509 int unit_merge_by_name(Unit *u, const char *name) {
 510         Unit *other;
 511         int r;
 512         char *s = NULL;
 513
 514         assert(u);
 515         assert(name);
 516
 517         if (unit_name_is_template(name)) {
 518                 if (!u->meta.instance)
 519                         return -EINVAL;
 520
 521                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 522                         return -ENOMEM;
 523
 524                 name = s;
 525         }
 526
 527         if (!(other = manager_get_unit(u->meta.manager, name)))
 528                 r = unit_add_name(u, name);
 529         else
 530                 r = unit_merge(u, other);
 531
 532         free(s);
 533         return r;
 534 }
 535
 536 Unit* unit_follow_merge(Unit *u) {
 537         assert(u);
 538
 539         while (u->meta.load_state == UNIT_MERGED)
 540                 assert_se(u = u->meta.merged_into);
 541
 542         return u;
 543 }
 544
 545 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 546         int r;
 547
 548         assert(u);
 549         assert(c);
 550
 551         if (c->std_output != EXEC_OUTPUT_KMSG &&
 552             c->std_output != EXEC_OUTPUT_SYSLOG &&
 553             c->std_error != EXEC_OUTPUT_KMSG &&
 554             c->std_error != EXEC_OUTPUT_SYSLOG)
 555                 return 0;
 556
 557         /* If syslog or kernel logging is requested, make sure our own
 558          * logging daemon is run first. */
 559
 560         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 561                 return r;
 562
 563         if (u->meta.manager->running_as == MANAGER_SYSTEM)
 564                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 565                         return r;
 566
 567         return 0;
 568 }
 569
 570 const char *unit_description(Unit *u) {
 571         assert(u);
 572
 573         if (u->meta.description)
 574                 return u->meta.description;
 575
 576         return u->meta.id;
 577 }
 578
 579 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 580         char *t;
 581         UnitDependency d;
 582         Iterator i;
 583         char *p2;
 584         const char *prefix2;
 585         CGroupBonding *b;
 586         char
 587                 timestamp1[FORMAT_TIMESTAMP_MAX],
 588                 timestamp2[FORMAT_TIMESTAMP_MAX],
 589                 timestamp3[FORMAT_TIMESTAMP_MAX],
 590                 timestamp4[FORMAT_TIMESTAMP_MAX];
 591
 592         assert(u);
 593         assert(u->meta.type >= 0);
 594
 595         if (!prefix)
 596                 prefix = "";
 597         p2 = strappend(prefix, "\t");
 598         prefix2 = p2 ? p2 : prefix;
 599
 600         fprintf(f,
 601                 "%s-> Unit %s:\n"
 602                 "%s\tDescription: %s\n"
 603                 "%s\tInstance: %s\n"
 604                 "%s\tUnit Load State: %s\n"
 605                 "%s\tUnit Active State: %s\n"
 606                 "%s\tInactive Exit Timestamp: %s\n"
 607                 "%s\tActive Enter Timestamp: %s\n"
 608                 "%s\tActive Exit Timestamp: %s\n"
 609                 "%s\tInactive Enter Timestamp: %s\n"
 610                 "%s\tGC Check Good: %s\n"
 611                 "%s\tNeed Daemon Reload: %s\n",
 612                 prefix, u->meta.id,
 613                 prefix, unit_description(u),
 614                 prefix, strna(u->meta.instance),
 615                 prefix, unit_load_state_to_string(u->meta.load_state),
 616                 prefix, unit_active_state_to_string(unit_active_state(u)),
 617                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 618                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 619                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 620                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 621                 prefix, yes_no(unit_check_gc(u)),
 622                 prefix, yes_no(unit_need_daemon_reload(u)));
 623
 624         SET_FOREACH(t, u->meta.names, i)
 625                 fprintf(f, "%s\tName: %s\n", prefix, t);
 626
 627         if (u->meta.fragment_path)
 628                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 629
 630         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 631                 Unit *other;
 632
 633                 SET_FOREACH(other, u->meta.dependencies[d], i)
 634                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 635         }
 636
 637         if (u->meta.load_state == UNIT_LOADED) {
 638                 fprintf(f,
 639                         "%s\tRecursive Stop: %s\n"
 640                         "%s\tStopWhenUnneeded: %s\n"
 641                         "%s\tOnlyByDependency: %s\n"
 642                         "%s\tDefaultDependencies: %s\n"
 643                         "%s\tIgnoreDependencyFailure: %s\n",
 644                         prefix, yes_no(u->meta.recursive_stop),
 645                         prefix, yes_no(u->meta.stop_when_unneeded),
 646                         prefix, yes_no(u->meta.only_by_dependency),
 647                         prefix, yes_no(u->meta.default_dependencies),
 648                         prefix, yes_no(u->meta.ignore_dependency_failure));
 649
 650                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 651                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 652                                 prefix, b->controller, b->path);
 653
 654                 if (UNIT_VTABLE(u)->dump)
 655                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 656
 657         } else if (u->meta.load_state == UNIT_MERGED)
 658                 fprintf(f,
 659                         "%s\tMerged into: %s\n",
 660                         prefix, u->meta.merged_into->meta.id);
 661
 662         if (u->meta.job)
 663                 job_dump(u->meta.job, f, prefix2);
 664
 665         free(p2);
 666 }
 667
 668 /* Common implementation for multiple backends */
 669 int unit_load_fragment_and_dropin(Unit *u) {
 670         int r;
 671
 672         assert(u);
 673
 674         /* Load a .service file */
 675         if ((r = unit_load_fragment(u)) < 0)
 676                 return r;
 677
 678         if (u->meta.load_state == UNIT_STUB)
 679                 return -ENOENT;
 680
 681         /* Load drop-in directory data */
 682         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 683                 return r;
 684
 685         return 0;
 686 }
 687
 688 /* Common implementation for multiple backends */
 689 int unit_load_fragment_and_dropin_optional(Unit *u) {
 690         int r;
 691
 692         assert(u);
 693
 694         /* Same as unit_load_fragment_and_dropin(), but whether
 695          * something can be loaded or not doesn't matter. */
 696
 697         /* Load a .service file */
 698         if ((r = unit_load_fragment(u)) < 0)
 699                 return r;
 700
 701         if (u->meta.load_state == UNIT_STUB)
 702                 u->meta.load_state = UNIT_LOADED;
 703
 704         /* Load drop-in directory data */
 705         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 706                 return r;
 707
 708         return 0;
 709 }
 710
 711 /* Common implementation for multiple backends */
 712 int unit_load_nop(Unit *u) {
 713         assert(u);
 714
 715         if (u->meta.load_state == UNIT_STUB)
 716                 u->meta.load_state = UNIT_LOADED;
 717
 718         return 0;
 719 }
 720
 721 int unit_load(Unit *u) {
 722         int r;
 723
 724         assert(u);
 725
 726         if (u->meta.in_load_queue) {
 727                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 728                 u->meta.in_load_queue = false;
 729         }
 730
 731         if (u->meta.type == _UNIT_TYPE_INVALID)
 732                 return -EINVAL;
 733
 734         if (u->meta.load_state != UNIT_STUB)
 735                 return 0;
 736
 737         if (UNIT_VTABLE(u)->load)
 738                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 739                         goto fail;
 740
 741         if (u->meta.load_state == UNIT_STUB) {
 742                 r = -ENOENT;
 743                 goto fail;
 744         }
 745
 746         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 747
 748         unit_add_to_dbus_queue(unit_follow_merge(u));
 749         unit_add_to_gc_queue(u);
 750
 751         return 0;
 752
 753 fail:
 754         u->meta.load_state = UNIT_FAILED;
 755         unit_add_to_dbus_queue(u);
 756
 757         log_notice("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 758
 759         return r;
 760 }
 761
 762 /* Errors:
 763  *         -EBADR:     This unit type does not support starting.
 764  *         -EALREADY:  Unit is already started.
 765  *         -EAGAIN:    An operation is already in progress. Retry later.
 766  *         -ECANCELED: Too many requests for now.
 767  */
 768 int unit_start(Unit *u) {
 769         UnitActiveState state;
 770
 771         assert(u);
 772
 773         if (u->meta.load_state != UNIT_LOADED)
 774                 return -EINVAL;
 775
 776         /* If this is already (being) started, then this will
 777          * succeed. Note that this will even succeed if this unit is
 778          * not startable by the user. This is relied on to detect when
 779          * we need to wait for units and when waiting is finished. */
 780         state = unit_active_state(u);
 781         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 782                 return -EALREADY;
 783
 784         /* If it is stopped, but we cannot start it, then fail */
 785         if (!UNIT_VTABLE(u)->start)
 786                 return -EBADR;
 787
 788         /* We don't suppress calls to ->start() here when we are
 789          * already starting, to allow this request to be used as a
 790          * "hurry up" call, for example when the unit is in some "auto
 791          * restart" state where it waits for a holdoff timer to elapse
 792          * before it will start again. */
 793
 794         unit_add_to_dbus_queue(u);
 795
 796         unit_status_printf(u, "Starting %s...\n", unit_description(u));
 797
 798         return UNIT_VTABLE(u)->start(u);
 799 }
 800
 801 bool unit_can_start(Unit *u) {
 802         assert(u);
 803
 804         return !!UNIT_VTABLE(u)->start;
 805 }
 806
 807 /* Errors:
 808  *         -EBADR:    This unit type does not support stopping.
 809  *         -EALREADY: Unit is already stopped.
 810  *         -EAGAIN:   An operation is already in progress. Retry later.
 811  */
 812 int unit_stop(Unit *u) {
 813         UnitActiveState state;
 814
 815         assert(u);
 816
 817         state = unit_active_state(u);
 818         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(state))
 819                 return -EALREADY;
 820
 821         if (!UNIT_VTABLE(u)->stop)
 822                 return -EBADR;
 823
 824         unit_add_to_dbus_queue(u);
 825
 826         unit_status_printf(u, "Stopping %s...\n", unit_description(u));
 827
 828         return UNIT_VTABLE(u)->stop(u);
 829 }
 830
 831 /* Errors:
 832  *         -EBADR:    This unit type does not support reloading.
 833  *         -ENOEXEC:  Unit is not started.
 834  *         -EAGAIN:   An operation is already in progress. Retry later.
 835  */
 836 int unit_reload(Unit *u) {
 837         UnitActiveState state;
 838
 839         assert(u);
 840
 841         if (u->meta.load_state != UNIT_LOADED)
 842                 return -EINVAL;
 843
 844         if (!unit_can_reload(u))
 845                 return -EBADR;
 846
 847         state = unit_active_state(u);
 848         if (unit_active_state(u) == UNIT_RELOADING)
 849                 return -EALREADY;
 850
 851         if (unit_active_state(u) != UNIT_ACTIVE)
 852                 return -ENOEXEC;
 853
 854         unit_add_to_dbus_queue(u);
 855         return UNIT_VTABLE(u)->reload(u);
 856 }
 857
 858 bool unit_can_reload(Unit *u) {
 859         assert(u);
 860
 861         if (!UNIT_VTABLE(u)->reload)
 862                 return false;
 863
 864         if (!UNIT_VTABLE(u)->can_reload)
 865                 return true;
 866
 867         return UNIT_VTABLE(u)->can_reload(u);
 868 }
 869
 870 static void unit_check_uneeded(Unit *u) {
 871         Iterator i;
 872         Unit *other;
 873
 874         assert(u);
 875
 876         /* If this service shall be shut down when unneeded then do
 877          * so. */
 878
 879         if (!u->meta.stop_when_unneeded)
 880                 return;
 881
 882         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 883                 return;
 884
 885         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 886                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 887                         return;
 888
 889         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 890                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 891                         return;
 892
 893         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 894                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 895                         return;
 896
 897         log_info("Service %s is not needed anymore. Stopping.", u->meta.id);
 898
 899         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 900         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL, NULL);
 901 }
 902
 903 static void retroactively_start_dependencies(Unit *u) {
 904         Iterator i;
 905         Unit *other;
 906
 907         assert(u);
 908         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
 909
 910         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 911                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 912                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
 913
 914         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 915                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 916                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
 917
 918         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 919                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 920                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
 921
 922         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 923                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 924                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
 925
 926         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
 927                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 928                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
 929 }
 930
 931 static void retroactively_stop_dependencies(Unit *u) {
 932         Iterator i;
 933         Unit *other;
 934
 935         assert(u);
 936         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
 937
 938         if (u->meta.recursive_stop) {
 939                 /* Pull down units need us recursively if enabled */
 940                 SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 941                         if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 942                                 manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
 943         }
 944
 945         /* Garbage collect services that might not be needed anymore, if enabled */
 946         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], 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_REQUIRES_OVERRIDABLE], 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_WANTS], 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], i)
 956                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 957                         unit_check_uneeded(other);
 958         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
 959                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 960                         unit_check_uneeded(other);
 961 }
 962
 963 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
 964         dual_timestamp ts;
 965         bool unexpected;
 966
 967         assert(u);
 968         assert(os < _UNIT_ACTIVE_STATE_MAX);
 969         assert(ns < _UNIT_ACTIVE_STATE_MAX);
 970
 971         /* Note that this is called for all low-level state changes,
 972          * even if they might map to the same high-level
 973          * UnitActiveState! That means that ns == os is OK an expected
 974          * behaviour here. For example: if a mount point is remounted
 975          * this function will be called too and the utmp code below
 976          * relies on that! */
 977
 978         dual_timestamp_get(&ts);
 979
 980         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && !UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 981                 u->meta.inactive_exit_timestamp = ts;
 982         else if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 983                 u->meta.inactive_enter_timestamp = ts;
 984
 985         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
 986                 u->meta.active_enter_timestamp = ts;
 987         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
 988                 u->meta.active_exit_timestamp = ts;
 989
 990         if (ns != os && ns == UNIT_MAINTENANCE)
 991                 log_notice("Unit %s entered maintenance state.", u->meta.id);
 992
 993         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 994                 cgroup_bonding_trim_list(u->meta.cgroup_bondings, true);
 995
 996         timer_unit_notify(u, ns);
 997         path_unit_notify(u, ns);
 998
 999         if (u->meta.job) {
1000                 unexpected = false;
1001
1002                 if (u->meta.job->state == JOB_WAITING)
1003
1004                         /* So we reached a different state for this
1005                          * job. Let's see if we can run it now if it
1006                          * failed previously due to EAGAIN. */
1007                         job_add_to_run_queue(u->meta.job);
1008
1009
1010                 /* Let's check whether this state change constitutes a
1011                  * finished job, or maybe cotradicts a running job and
1012                  * hence needs to invalidate jobs. */
1013
1014                 switch (u->meta.job->type) {
1015
1016                 case JOB_START:
1017                 case JOB_VERIFY_ACTIVE:
1018
1019                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
1020                                 job_finish_and_invalidate(u->meta.job, true);
1021                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
1022                                 unexpected = true;
1023                                 job_finish_and_invalidate(u->meta.job, false);
1024                         }
1025
1026                         break;
1027
1028                 case JOB_RELOAD:
1029                 case JOB_RELOAD_OR_START:
1030
1031                         if (u->meta.job->state == JOB_RUNNING) {
1032                                 if (ns == UNIT_ACTIVE)
1033                                         job_finish_and_invalidate(u->meta.job, true);
1034                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
1035                                         unexpected = true;
1036                                         job_finish_and_invalidate(u->meta.job, false);
1037                                 }
1038                         }
1039
1040                         break;
1041
1042                 case JOB_STOP:
1043                 case JOB_RESTART:
1044                 case JOB_TRY_RESTART:
1045
1046                         if (ns == UNIT_INACTIVE || ns == UNIT_MAINTENANCE)
1047                                 job_finish_and_invalidate(u->meta.job, true);
1048                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1049                                 unexpected = true;
1050                                 job_finish_and_invalidate(u->meta.job, false);
1051                         }
1052
1053                         break;
1054
1055                 default:
1056                         assert_not_reached("Job type unknown");
1057                 }
1058
1059         } else
1060                 unexpected = true;
1061
1062         /* If this state change happened without being requested by a
1063          * job, then let's retroactively start or stop
1064          * dependencies. We skip that step when deserializing, since
1065          * we don't want to create any additional jobs just because
1066          * something is already activated. */
1067
1068         if (unexpected && u->meta.manager->n_deserializing <= 0) {
1069                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1070                         retroactively_start_dependencies(u);
1071                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1072                         retroactively_stop_dependencies(u);
1073         }
1074
1075         /* Some names are special */
1076         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1077                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1078                         /* The bus just might have become available,
1079                          * hence try to connect to it, if we aren't
1080                          * yet connected. */
1081                         bus_init(u->meta.manager);
1082                 }
1083
1084                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1085                         /* The syslog daemon just might have become
1086                          * available, hence try to connect to it, if
1087                          * we aren't yet connected. */
1088                         log_open();
1089
1090                 if (u->meta.type == UNIT_MOUNT)
1091                         /* Another directory became available, let's
1092                          * check if that is enough to write our utmp
1093                          * entry. */
1094                         manager_write_utmp_reboot(u->meta.manager);
1095
1096                 if (u->meta.type == UNIT_TARGET)
1097                         /* A target got activated, maybe this is a runlevel? */
1098                         manager_write_utmp_runlevel(u->meta.manager, u);
1099
1100         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1101
1102                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1103                         /* The syslog daemon might just have
1104                          * terminated, hence try to disconnect from
1105                          * it. */
1106                         log_close_syslog();
1107
1108                 /* We don't care about D-Bus here, since we'll get an
1109                  * asynchronous notification for it anyway. */
1110         }
1111
1112         /* Maybe we finished startup and are now ready for being
1113          * stopped because unneeded? */
1114         unit_check_uneeded(u);
1115
1116         unit_add_to_dbus_queue(u);
1117         unit_add_to_gc_queue(u);
1118 }
1119
1120 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1121         struct epoll_event ev;
1122
1123         assert(u);
1124         assert(fd >= 0);
1125         assert(w);
1126         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1127
1128         zero(ev);
1129         ev.data.ptr = w;
1130         ev.events = events;
1131
1132         if (epoll_ctl(u->meta.manager->epoll_fd,
1133                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1134                       fd,
1135                       &ev) < 0)
1136                 return -errno;
1137
1138         w->fd = fd;
1139         w->type = WATCH_FD;
1140         w->data.unit = u;
1141
1142         return 0;
1143 }
1144
1145 void unit_unwatch_fd(Unit *u, Watch *w) {
1146         assert(u);
1147         assert(w);
1148
1149         if (w->type == WATCH_INVALID)
1150                 return;
1151
1152         assert(w->type == WATCH_FD);
1153         assert(w->data.unit == u);
1154         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1155
1156         w->fd = -1;
1157         w->type = WATCH_INVALID;
1158         w->data.unit = NULL;
1159 }
1160
1161 int unit_watch_pid(Unit *u, pid_t pid) {
1162         assert(u);
1163         assert(pid >= 1);
1164
1165         /* Watch a specific PID. We only support one unit watching
1166          * each PID for now. */
1167
1168         return hashmap_put(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1169 }
1170
1171 void unit_unwatch_pid(Unit *u, pid_t pid) {
1172         assert(u);
1173         assert(pid >= 1);
1174
1175         hashmap_remove_value(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1176 }
1177
1178 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1179         struct itimerspec its;
1180         int flags, fd;
1181         bool ours;
1182
1183         assert(u);
1184         assert(w);
1185         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1186
1187         /* This will try to reuse the old timer if there is one */
1188
1189         if (w->type == WATCH_TIMER) {
1190                 ours = false;
1191                 fd = w->fd;
1192         } else {
1193                 ours = true;
1194                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1195                         return -errno;
1196         }
1197
1198         zero(its);
1199
1200         if (delay <= 0) {
1201                 /* Set absolute time in the past, but not 0, since we
1202                  * don't want to disarm the timer */
1203                 its.it_value.tv_sec = 0;
1204                 its.it_value.tv_nsec = 1;
1205
1206                 flags = TFD_TIMER_ABSTIME;
1207         } else {
1208                 timespec_store(&its.it_value, delay);
1209                 flags = 0;
1210         }
1211
1212         /* This will also flush the elapse counter */
1213         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1214                 goto fail;
1215
1216         if (w->type == WATCH_INVALID) {
1217                 struct epoll_event ev;
1218
1219                 zero(ev);
1220                 ev.data.ptr = w;
1221                 ev.events = EPOLLIN;
1222
1223                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1224                         goto fail;
1225         }
1226
1227         w->fd = fd;
1228         w->type = WATCH_TIMER;
1229         w->data.unit = u;
1230
1231         return 0;
1232
1233 fail:
1234         if (ours)
1235                 close_nointr_nofail(fd);
1236
1237         return -errno;
1238 }
1239
1240 void unit_unwatch_timer(Unit *u, Watch *w) {
1241         assert(u);
1242         assert(w);
1243
1244         if (w->type == WATCH_INVALID)
1245                 return;
1246
1247         assert(w->type == WATCH_TIMER && w->data.unit == u);
1248
1249         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1250         close_nointr_nofail(w->fd);
1251
1252         w->fd = -1;
1253         w->type = WATCH_INVALID;
1254         w->data.unit = NULL;
1255 }
1256
1257 bool unit_job_is_applicable(Unit *u, JobType j) {
1258         assert(u);
1259         assert(j >= 0 && j < _JOB_TYPE_MAX);
1260
1261         switch (j) {
1262
1263         case JOB_VERIFY_ACTIVE:
1264         case JOB_START:
1265                 return true;
1266
1267         case JOB_STOP:
1268         case JOB_RESTART:
1269         case JOB_TRY_RESTART:
1270                 return unit_can_start(u);
1271
1272         case JOB_RELOAD:
1273                 return unit_can_reload(u);
1274
1275         case JOB_RELOAD_OR_START:
1276                 return unit_can_reload(u) && unit_can_start(u);
1277
1278         default:
1279                 assert_not_reached("Invalid job type");
1280         }
1281 }
1282
1283 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1284
1285         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1286                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1287                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1288                 [UNIT_WANTS] = UNIT_WANTED_BY,
1289                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1290                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1291                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1292                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1293                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1294                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1295                 [UNIT_BEFORE] = UNIT_AFTER,
1296                 [UNIT_AFTER] = UNIT_BEFORE,
1297                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1298                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1299         };
1300         int r, q = 0, v = 0, w = 0;
1301
1302         assert(u);
1303         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1304         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1305         assert(other);
1306
1307         /* We won't allow dependencies on ourselves. We will not
1308          * consider them an error however. */
1309         if (u == other)
1310                 return 0;
1311
1312         if (UNIT_VTABLE(u)->no_requires &&
1313             (d == UNIT_REQUIRES ||
1314              d == UNIT_REQUIRES_OVERRIDABLE ||
1315              d == UNIT_REQUISITE ||
1316              d == UNIT_REQUISITE_OVERRIDABLE)) {
1317                     return -EINVAL;
1318         }
1319
1320         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1321             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1322                 return r;
1323
1324         if (add_reference)
1325                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1326                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1327                         return r;
1328
1329         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1330                 return q;
1331
1332         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1333                 r = v;
1334                 goto fail;
1335         }
1336
1337         if (add_reference) {
1338                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1339                         r = w;
1340                         goto fail;
1341                 }
1342
1343                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1344                         goto fail;
1345         }
1346
1347         unit_add_to_dbus_queue(u);
1348         return 0;
1349
1350 fail:
1351         if (q > 0)
1352                 set_remove(u->meta.dependencies[d], other);
1353
1354         if (v > 0)
1355                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1356
1357         if (w > 0)
1358                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1359
1360         return r;
1361 }
1362
1363 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference) {
1364         int r;
1365
1366         assert(u);
1367
1368         if ((r = unit_add_dependency(u, d, other, add_reference)) < 0)
1369                 return r;
1370
1371         if ((r = unit_add_dependency(u, e, other, add_reference)) < 0)
1372                 return r;
1373
1374         return 0;
1375 }
1376
1377 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1378         char *s;
1379
1380         assert(u);
1381         assert(name || path);
1382
1383         if (!name)
1384                 name = file_name_from_path(path);
1385
1386         if (!unit_name_is_template(name)) {
1387                 *p = NULL;
1388                 return name;
1389         }
1390
1391         if (u->meta.instance)
1392                 s = unit_name_replace_instance(name, u->meta.instance);
1393         else {
1394                 char *i;
1395
1396                 if (!(i = unit_name_to_prefix(u->meta.id)))
1397                         return NULL;
1398
1399                 s = unit_name_replace_instance(name, i);
1400                 free(i);
1401         }
1402
1403         if (!s)
1404                 return NULL;
1405
1406         *p = s;
1407         return s;
1408 }
1409
1410 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1411         Unit *other;
1412         int r;
1413         char *s;
1414
1415         assert(u);
1416         assert(name || path);
1417
1418         if (!(name = resolve_template(u, name, path, &s)))
1419                 return -ENOMEM;
1420
1421         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1422                 goto finish;
1423
1424         r = unit_add_dependency(u, d, other, add_reference);
1425
1426 finish:
1427         free(s);
1428         return r;
1429 }
1430
1431 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1432         Unit *other;
1433         int r;
1434         char *s;
1435
1436         assert(u);
1437         assert(name || path);
1438
1439         if (!(name = resolve_template(u, name, path, &s)))
1440                 return -ENOMEM;
1441
1442         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1443                 goto finish;
1444
1445         r = unit_add_two_dependencies(u, d, e, other, add_reference);
1446
1447 finish:
1448         free(s);
1449         return r;
1450 }
1451
1452 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1453         Unit *other;
1454         int r;
1455         char *s;
1456
1457         assert(u);
1458         assert(name || path);
1459
1460         if (!(name = resolve_template(u, name, path, &s)))
1461                 return -ENOMEM;
1462
1463         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1464                 goto finish;
1465
1466         r = unit_add_dependency(other, d, u, add_reference);
1467
1468 finish:
1469         free(s);
1470         return r;
1471 }
1472
1473 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1474         Unit *other;
1475         int r;
1476         char *s;
1477
1478         assert(u);
1479         assert(name || path);
1480
1481         if (!(name = resolve_template(u, name, path, &s)))
1482                 return -ENOMEM;
1483
1484         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1485                 goto finish;
1486
1487         if ((r = unit_add_two_dependencies(other, d, e, u, add_reference)) < 0)
1488                 goto finish;
1489
1490 finish:
1491         free(s);
1492         return r;
1493 }
1494
1495 int set_unit_path(const char *p) {
1496         char *cwd, *c;
1497         int r;
1498
1499         /* This is mostly for debug purposes */
1500
1501         if (path_is_absolute(p)) {
1502                 if (!(c = strdup(p)))
1503                         return -ENOMEM;
1504         } else {
1505                 if (!(cwd = get_current_dir_name()))
1506                         return -errno;
1507
1508                 r = asprintf(&c, "%s/%s", cwd, p);
1509                 free(cwd);
1510
1511                 if (r < 0)
1512                         return -ENOMEM;
1513         }
1514
1515         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1516                 r = -errno;
1517                 free(c);
1518                 return r;
1519         }
1520
1521         return 0;
1522 }
1523
1524 char *unit_dbus_path(Unit *u) {
1525         char *p, *e;
1526
1527         assert(u);
1528
1529         if (!(e = bus_path_escape(u->meta.id)))
1530                 return NULL;
1531
1532         p = strappend("/org/freedesktop/systemd1/unit/", e);
1533         free(e);
1534
1535         return p;
1536 }
1537
1538 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1539         CGroupBonding *l;
1540         int r;
1541
1542         assert(u);
1543         assert(b);
1544
1545         assert(b->path);
1546
1547         if (!b->controller)
1548                 if (!(b->controller = strdup(SYSTEMD_CGROUP_CONTROLLER)))
1549                         return -ENOMEM;
1550
1551         /* Ensure this hasn't been added yet */
1552         assert(!b->unit);
1553
1554         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1555         LIST_PREPEND(CGroupBonding, by_path, l, b);
1556
1557         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1558                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1559                 return r;
1560         }
1561
1562         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1563         b->unit = u;
1564
1565         return 0;
1566 }
1567
1568 static char *default_cgroup_path(Unit *u) {
1569         char *p;
1570         int r;
1571
1572         assert(u);
1573
1574         if (u->meta.instance) {
1575                 char *t;
1576
1577                 if (!(t = unit_name_template(u->meta.id)))
1578                         return NULL;
1579
1580                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1581                 free(t);
1582         } else
1583                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1584
1585         return r < 0 ? NULL : p;
1586 }
1587
1588 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1589         char *controller = NULL, *path = NULL;
1590         CGroupBonding *b = NULL;
1591         int r;
1592
1593         assert(u);
1594         assert(name);
1595
1596         if ((r = cg_split_spec(name, &controller, &path)) < 0)
1597                 return r;
1598
1599         if (!path)
1600                 path = default_cgroup_path(u);
1601
1602         if (!controller)
1603                 controller = strdup(SYSTEMD_CGROUP_CONTROLLER);
1604
1605         if (!path || !controller) {
1606                 free(path);
1607                 free(controller);
1608
1609                 return -ENOMEM;
1610         }
1611
1612         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1613                 r = -EEXIST;
1614                 goto fail;
1615         }
1616
1617         if (!(b = new0(CGroupBonding, 1))) {
1618                 r = -ENOMEM;
1619                 goto fail;
1620         }
1621
1622         b->controller = controller;
1623         b->path = path;
1624         b->only_us = false;
1625         b->clean_up = false;
1626
1627         if ((r = unit_add_cgroup(u, b)) < 0)
1628                 goto fail;
1629
1630         return 0;
1631
1632 fail:
1633         free(path);
1634         free(controller);
1635         free(b);
1636
1637         return r;
1638 }
1639
1640 int unit_add_default_cgroup(Unit *u) {
1641         CGroupBonding *b;
1642         int r = -ENOMEM;
1643
1644         assert(u);
1645
1646         /* Adds in the default cgroup data, if it wasn't specified yet */
1647
1648         if (unit_get_default_cgroup(u))
1649                 return 0;
1650
1651         if (!(b = new0(CGroupBonding, 1)))
1652                 return -ENOMEM;
1653
1654         if (!(b->path = default_cgroup_path(u)))
1655                 goto fail;
1656
1657         b->clean_up = true;
1658         b->only_us = true;
1659
1660         if ((r = unit_add_cgroup(u, b)) < 0)
1661                 goto fail;
1662
1663         return 0;
1664
1665 fail:
1666         free(b->path);
1667         free(b->controller);
1668         free(b);
1669
1670         return r;
1671 }
1672
1673 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1674         assert(u);
1675
1676         return cgroup_bonding_find_list(u->meta.cgroup_bondings, SYSTEMD_CGROUP_CONTROLLER);
1677 }
1678
1679 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1680         char *t;
1681         int r;
1682
1683         assert(u);
1684         assert(type);
1685         assert(_found);
1686
1687         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1688                 return -ENOMEM;
1689
1690         assert(!unit_has_name(u, t));
1691
1692         r = manager_load_unit(u->meta.manager, t, NULL, NULL, _found);
1693         free(t);
1694
1695         assert(r < 0 || *_found != u);
1696
1697         return r;
1698 }
1699
1700 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1701         Unit *found;
1702         char *t;
1703
1704         assert(u);
1705         assert(type);
1706         assert(_found);
1707
1708         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1709                 return -ENOMEM;
1710
1711         assert(!unit_has_name(u, t));
1712
1713         found = manager_get_unit(u->meta.manager, t);
1714         free(t);
1715
1716         if (!found)
1717                 return -ENOENT;
1718
1719         *_found = found;
1720         return 0;
1721 }
1722
1723 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1724         Unit *u = userdata;
1725         assert(u);
1726
1727         return unit_name_to_prefix_and_instance(u->meta.id);
1728 }
1729
1730 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1731         Unit *u = userdata;
1732         assert(u);
1733
1734         return unit_name_to_prefix(u->meta.id);
1735 }
1736
1737 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1738         Unit *u = userdata;
1739         char *p, *r;
1740
1741         assert(u);
1742
1743         if (!(p = unit_name_to_prefix(u->meta.id)))
1744                 return NULL;
1745
1746         r = unit_name_unescape(p);
1747         free(p);
1748
1749         return r;
1750 }
1751
1752 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1753         Unit *u = userdata;
1754         assert(u);
1755
1756         if (u->meta.instance)
1757                 return unit_name_unescape(u->meta.instance);
1758
1759         return strdup("");
1760 }
1761
1762 char *unit_name_printf(Unit *u, const char* format) {
1763
1764         /*
1765          * This will use the passed string as format string and
1766          * replace the following specifiers:
1767          *
1768          * %n: the full id of the unit                 (foo@bar.waldo)
1769          * %N: the id of the unit without the suffix   (foo@bar)
1770          * %p: the prefix                              (foo)
1771          * %i: the instance                            (bar)
1772          */
1773
1774         const Specifier table[] = {
1775                 { 'n', specifier_string,              u->meta.id },
1776                 { 'N', specifier_prefix_and_instance, NULL },
1777                 { 'p', specifier_prefix,              NULL },
1778                 { 'i', specifier_string,              u->meta.instance },
1779                 { 0, NULL, NULL }
1780         };
1781
1782         assert(u);
1783         assert(format);
1784
1785         return specifier_printf(format, table, u);
1786 }
1787
1788 char *unit_full_printf(Unit *u, const char *format) {
1789
1790         /* This is similar to unit_name_printf() but also supports
1791          * unescaping */
1792
1793         const Specifier table[] = {
1794                 { 'n', specifier_string,              u->meta.id },
1795                 { 'N', specifier_prefix_and_instance, NULL },
1796                 { 'p', specifier_prefix,              NULL },
1797                 { 'P', specifier_prefix_unescaped,    NULL },
1798                 { 'i', specifier_string,              u->meta.instance },
1799                 { 'I', specifier_instance_unescaped,  NULL },
1800                 { 0, NULL, NULL }
1801         };
1802
1803         assert(u);
1804         assert(format);
1805
1806         return specifier_printf(format, table, u);
1807 }
1808
1809 char **unit_full_printf_strv(Unit *u, char **l) {
1810         size_t n;
1811         char **r, **i, **j;
1812
1813         /* Applies unit_full_printf to every entry in l */
1814
1815         assert(u);
1816
1817         n = strv_length(l);
1818         if (!(r = new(char*, n+1)))
1819                 return NULL;
1820
1821         for (i = l, j = r; *i; i++, j++)
1822                 if (!(*j = unit_full_printf(u, *i)))
1823                         goto fail;
1824
1825         *j = NULL;
1826         return r;
1827
1828 fail:
1829         j--;
1830         while (j >= r)
1831                 free(*j);
1832
1833         free(r);
1834
1835         return NULL;
1836 }
1837
1838 int unit_watch_bus_name(Unit *u, const char *name) {
1839         assert(u);
1840         assert(name);
1841
1842         /* Watch a specific name on the bus. We only support one unit
1843          * watching each name for now. */
1844
1845         return hashmap_put(u->meta.manager->watch_bus, name, u);
1846 }
1847
1848 void unit_unwatch_bus_name(Unit *u, const char *name) {
1849         assert(u);
1850         assert(name);
1851
1852         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1853 }
1854
1855 bool unit_can_serialize(Unit *u) {
1856         assert(u);
1857
1858         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1859 }
1860
1861 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1862         int r;
1863
1864         assert(u);
1865         assert(f);
1866         assert(fds);
1867
1868         if (!unit_can_serialize(u))
1869                 return 0;
1870
1871         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1872                 return r;
1873
1874         if (u->meta.job)
1875                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1876
1877         /* End marker */
1878         fputc('\n', f);
1879         return 0;
1880 }
1881
1882 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1883         va_list ap;
1884
1885         assert(u);
1886         assert(f);
1887         assert(key);
1888         assert(format);
1889
1890         fputs(key, f);
1891         fputc('=', f);
1892
1893         va_start(ap, format);
1894         vfprintf(f, format, ap);
1895         va_end(ap);
1896
1897         fputc('\n', f);
1898 }
1899
1900 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1901         assert(u);
1902         assert(f);
1903         assert(key);
1904         assert(value);
1905
1906         fprintf(f, "%s=%s\n", key, value);
1907 }
1908
1909 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1910         int r;
1911
1912         assert(u);
1913         assert(f);
1914         assert(fds);
1915
1916         if (!unit_can_serialize(u))
1917                 return 0;
1918
1919         for (;;) {
1920                 char line[1024], *l, *v;
1921                 size_t k;
1922
1923                 if (!fgets(line, sizeof(line), f)) {
1924                         if (feof(f))
1925                                 return 0;
1926                         return -errno;
1927                 }
1928
1929                 l = strstrip(line);
1930
1931                 /* End marker */
1932                 if (l[0] == 0)
1933                         return 0;
1934
1935                 k = strcspn(l, "=");
1936
1937                 if (l[k] == '=') {
1938                         l[k] = 0;
1939                         v = l+k+1;
1940                 } else
1941                         v = l+k;
1942
1943                 if (streq(l, "job")) {
1944                         JobType type;
1945
1946                         if ((type = job_type_from_string(v)) < 0)
1947                                 log_debug("Failed to parse job type value %s", v);
1948                         else
1949                                 u->meta.deserialized_job = type;
1950
1951                         continue;
1952                 }
1953
1954                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1955                         return r;
1956         }
1957 }
1958
1959 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1960         Unit *device;
1961         char *e;
1962         int r;
1963
1964         assert(u);
1965
1966         if (!what)
1967                 return 0;
1968
1969         /* Adds in links to the device node that this unit is based on */
1970
1971         if (!is_device_path(what))
1972                 return 0;
1973
1974         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1975                 return -ENOMEM;
1976
1977         r = manager_load_unit(u->meta.manager, e, NULL, NULL, &device);
1978         free(e);
1979
1980         if (r < 0)
1981                 return r;
1982
1983         if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_REQUIRES, device, true)) < 0)
1984                 return r;
1985
1986         if (wants)
1987                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1988                         return r;
1989
1990         return 0;
1991 }
1992
1993 int unit_coldplug(Unit *u) {
1994         int r;
1995
1996         assert(u);
1997
1998         if (UNIT_VTABLE(u)->coldplug)
1999                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
2000                         return r;
2001
2002         if (u->meta.deserialized_job >= 0) {
2003                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL, NULL)) < 0)
2004                         return r;
2005
2006                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
2007         }
2008
2009         return 0;
2010 }
2011
2012 void unit_status_printf(Unit *u, const char *format, ...) {
2013         va_list ap;
2014
2015         assert(u);
2016         assert(format);
2017
2018         if (!UNIT_VTABLE(u)->show_status)
2019                 return;
2020
2021         if (u->meta.manager->running_as != MANAGER_SYSTEM)
2022                 return;
2023
2024         if (!u->meta.manager->show_status)
2025                 return;
2026
2027         if (!manager_is_booting_or_shutting_down(u->meta.manager))
2028                 return;
2029
2030         va_start(ap, format);
2031         status_vprintf(format, ap);
2032         va_end(ap);
2033 }
2034
2035 bool unit_need_daemon_reload(Unit *u) {
2036         struct stat st;
2037
2038         assert(u);
2039
2040         if (!u->meta.fragment_path)
2041                 return false;
2042
2043         zero(st);
2044         if (stat(u->meta.fragment_path, &st) < 0)
2045                 /* What, cannot access this anymore? */
2046                 return true;
2047
2048         return
2049                 u->meta.fragment_mtime &&
2050                 timespec_load(&st.st_mtim) != u->meta.fragment_mtime;
2051 }
2052
2053 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
2054         [UNIT_SERVICE] = "service",
2055         [UNIT_TIMER] = "timer",
2056         [UNIT_SOCKET] = "socket",
2057         [UNIT_TARGET] = "target",
2058         [UNIT_DEVICE] = "device",
2059         [UNIT_MOUNT] = "mount",
2060         [UNIT_AUTOMOUNT] = "automount",
2061         [UNIT_SNAPSHOT] = "snapshot",
2062         [UNIT_SWAP] = "swap"
2063 };
2064
2065 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
2066
2067 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
2068         [UNIT_STUB] = "stub",
2069         [UNIT_LOADED] = "loaded",
2070         [UNIT_FAILED] = "failed",
2071         [UNIT_MERGED] = "merged"
2072 };
2073
2074 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
2075
2076 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
2077         [UNIT_ACTIVE] = "active",
2078         [UNIT_RELOADING] = "reloading",
2079         [UNIT_INACTIVE] = "inactive",
2080         [UNIT_MAINTENANCE] = "maintenance",
2081         [UNIT_ACTIVATING] = "activating",
2082         [UNIT_DEACTIVATING] = "deactivating"
2083 };
2084
2085 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
2086
2087 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
2088         [UNIT_REQUIRES] = "Requires",
2089         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
2090         [UNIT_WANTS] = "Wants",
2091         [UNIT_REQUISITE] = "Requisite",
2092         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
2093         [UNIT_REQUIRED_BY] = "RequiredBy",
2094         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
2095         [UNIT_WANTED_BY] = "WantedBy",
2096         [UNIT_CONFLICTS] = "Conflicts",
2097         [UNIT_BEFORE] = "Before",
2098         [UNIT_AFTER] = "After",
2099         [UNIT_REFERENCES] = "References",
2100         [UNIT_REFERENCED_BY] = "ReferencedBy"
2101 };
2102
2103 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
2104
2105 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2106         [KILL_CONTROL_GROUP] = "control-group",
2107         [KILL_PROCESS_GROUP] = "process-group",
2108         [KILL_PROCESS] = "process",
2109         [KILL_NONE] = "none"
2110 };
2111
2112 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);