src/unit.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   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 #include "missing.h"
  45
  46 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  47         [UNIT_SERVICE] = &service_vtable,
  48         [UNIT_TIMER] = &timer_vtable,
  49         [UNIT_SOCKET] = &socket_vtable,
  50         [UNIT_TARGET] = &target_vtable,
  51         [UNIT_DEVICE] = &device_vtable,
  52         [UNIT_MOUNT] = &mount_vtable,
  53         [UNIT_AUTOMOUNT] = &automount_vtable,
  54         [UNIT_SNAPSHOT] = &snapshot_vtable,
  55         [UNIT_SWAP] = &swap_vtable,
  56         [UNIT_PATH] = &path_vtable
  57 };
  58
  59 Unit *unit_new(Manager *m) {
  60         Unit *u;
  61
  62         assert(m);
  63
  64         if (!(u = new0(Unit, 1)))
  65                 return NULL;
  66
  67         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  68                 free(u);
  69                 return NULL;
  70         }
  71
  72         u->meta.manager = m;
  73         u->meta.type = _UNIT_TYPE_INVALID;
  74         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  75         u->meta.default_dependencies = true;
  76
  77         return u;
  78 }
  79
  80 bool unit_has_name(Unit *u, const char *name) {
  81         assert(u);
  82         assert(name);
  83
  84         return !!set_get(u->meta.names, (char*) name);
  85 }
  86
  87 int unit_add_name(Unit *u, const char *text) {
  88         UnitType t;
  89         char *s, *i = NULL;
  90         int r;
  91
  92         assert(u);
  93         assert(text);
  94
  95         if (unit_name_is_template(text)) {
  96                 if (!u->meta.instance)
  97                         return -EINVAL;
  98
  99                 s = unit_name_replace_instance(text, u->meta.instance);
 100         } else
 101                 s = strdup(text);
 102
 103         if (!s)
 104                 return -ENOMEM;
 105
 106         if (!unit_name_is_valid(s, false)) {
 107                 r = -EINVAL;
 108                 goto fail;
 109         }
 110
 111         assert_se((t = unit_name_to_type(s)) >= 0);
 112
 113         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 114                 r = -EINVAL;
 115                 goto fail;
 116         }
 117
 118         if ((r = unit_name_to_instance(s, &i)) < 0)
 119                 goto fail;
 120
 121         if (i && unit_vtable[t]->no_instances)
 122                 goto fail;
 123
 124         /* Ensure that this unit is either instanced or not instanced,
 125          * but not both. */
 126         if (u->meta.type != _UNIT_TYPE_INVALID && !u->meta.instance != !i) {
 127                 r = -EINVAL;
 128                 goto fail;
 129         }
 130
 131         if (unit_vtable[t]->no_alias &&
 132             !set_isempty(u->meta.names) &&
 133             !set_get(u->meta.names, s)) {
 134                 r = -EEXIST;
 135                 goto fail;
 136         }
 137
 138         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 139                 r = -E2BIG;
 140                 goto fail;
 141         }
 142
 143         if ((r = set_put(u->meta.names, s)) < 0) {
 144                 if (r == -EEXIST)
 145                         r = 0;
 146                 goto fail;
 147         }
 148
 149         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 150                 set_remove(u->meta.names, s);
 151                 goto fail;
 152         }
 153
 154         if (u->meta.type == _UNIT_TYPE_INVALID) {
 155
 156                 u->meta.type = t;
 157                 u->meta.id = s;
 158                 u->meta.instance = i;
 159
 160                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 161
 162                 if (UNIT_VTABLE(u)->init)
 163                         UNIT_VTABLE(u)->init(u);
 164         } else
 165                 free(i);
 166
 167         unit_add_to_dbus_queue(u);
 168         return 0;
 169
 170 fail:
 171         free(s);
 172         free(i);
 173
 174         return r;
 175 }
 176
 177 int unit_choose_id(Unit *u, const char *name) {
 178         char *s, *t = NULL, *i;
 179         int r;
 180
 181         assert(u);
 182         assert(name);
 183
 184         if (unit_name_is_template(name)) {
 185
 186                 if (!u->meta.instance)
 187                         return -EINVAL;
 188
 189                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 190                         return -ENOMEM;
 191
 192                 name = t;
 193         }
 194
 195         /* Selects one of the names of this unit as the id */
 196         s = set_get(u->meta.names, (char*) name);
 197         free(t);
 198
 199         if (!s)
 200                 return -ENOENT;
 201
 202         if ((r = unit_name_to_instance(s, &i)) < 0)
 203                 return r;
 204
 205         u->meta.id = s;
 206
 207         free(u->meta.instance);
 208         u->meta.instance = i;
 209
 210         unit_add_to_dbus_queue(u);
 211
 212         return 0;
 213 }
 214
 215 int unit_set_description(Unit *u, const char *description) {
 216         char *s;
 217
 218         assert(u);
 219
 220         if (!(s = strdup(description)))
 221                 return -ENOMEM;
 222
 223         free(u->meta.description);
 224         u->meta.description = s;
 225
 226         unit_add_to_dbus_queue(u);
 227         return 0;
 228 }
 229
 230 bool unit_check_gc(Unit *u) {
 231         assert(u);
 232
 233         if (u->meta.load_state == UNIT_STUB)
 234                 return true;
 235
 236         if (UNIT_VTABLE(u)->no_gc)
 237                 return true;
 238
 239         if (u->meta.no_gc)
 240                 return true;
 241
 242         if (u->meta.job)
 243                 return true;
 244
 245         if (unit_active_state(u) != UNIT_INACTIVE)
 246                 return true;
 247
 248         if (UNIT_VTABLE(u)->check_gc)
 249                 if (UNIT_VTABLE(u)->check_gc(u))
 250                         return true;
 251
 252         return false;
 253 }
 254
 255 void unit_add_to_load_queue(Unit *u) {
 256         assert(u);
 257         assert(u->meta.type != _UNIT_TYPE_INVALID);
 258
 259         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 260                 return;
 261
 262         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 263         u->meta.in_load_queue = true;
 264 }
 265
 266 void unit_add_to_cleanup_queue(Unit *u) {
 267         assert(u);
 268
 269         if (u->meta.in_cleanup_queue)
 270                 return;
 271
 272         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 273         u->meta.in_cleanup_queue = true;
 274 }
 275
 276 void unit_add_to_gc_queue(Unit *u) {
 277         assert(u);
 278
 279         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 280                 return;
 281
 282         if (unit_check_gc(u))
 283                 return;
 284
 285         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 286         u->meta.in_gc_queue = true;
 287
 288         u->meta.manager->n_in_gc_queue ++;
 289
 290         if (u->meta.manager->gc_queue_timestamp <= 0)
 291                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 292 }
 293
 294 void unit_add_to_dbus_queue(Unit *u) {
 295         assert(u);
 296         assert(u->meta.type != _UNIT_TYPE_INVALID);
 297
 298         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 299                 return;
 300
 301         /* Shortcut things if nobody cares */
 302         if (!bus_has_subscriber(u->meta.manager)) {
 303                 u->meta.sent_dbus_new_signal = true;
 304                 return;
 305         }
 306
 307         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 308         u->meta.in_dbus_queue = true;
 309 }
 310
 311 static void bidi_set_free(Unit *u, Set *s) {
 312         Iterator i;
 313         Unit *other;
 314
 315         assert(u);
 316
 317         /* Frees the set and makes sure we are dropped from the
 318          * inverse pointers */
 319
 320         SET_FOREACH(other, s, i) {
 321                 UnitDependency d;
 322
 323                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 324                         set_remove(other->meta.dependencies[d], u);
 325
 326                 unit_add_to_gc_queue(other);
 327         }
 328
 329         set_free(s);
 330 }
 331
 332 void unit_free(Unit *u) {
 333         UnitDependency d;
 334         Iterator i;
 335         char *t;
 336
 337         assert(u);
 338
 339         bus_unit_send_removed_signal(u);
 340
 341         if (u->meta.load_state != UNIT_STUB)
 342                 if (UNIT_VTABLE(u)->done)
 343                         UNIT_VTABLE(u)->done(u);
 344
 345         SET_FOREACH(t, u->meta.names, i)
 346                 hashmap_remove_value(u->meta.manager->units, t, u);
 347
 348         if (u->meta.job)
 349                 job_free(u->meta.job);
 350
 351         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 352                 bidi_set_free(u, u->meta.dependencies[d]);
 353
 354         if (u->meta.type != _UNIT_TYPE_INVALID)
 355                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 356
 357         if (u->meta.in_load_queue)
 358                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 359
 360         if (u->meta.in_dbus_queue)
 361                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 362
 363         if (u->meta.in_cleanup_queue)
 364                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 365
 366         if (u->meta.in_gc_queue) {
 367                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 368                 u->meta.manager->n_in_gc_queue--;
 369         }
 370
 371         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 372
 373         free(u->meta.description);
 374         free(u->meta.fragment_path);
 375
 376         set_free_free(u->meta.names);
 377
 378         condition_free_list(u->meta.conditions);
 379
 380         free(u->meta.instance);
 381         free(u);
 382 }
 383
 384 UnitActiveState unit_active_state(Unit *u) {
 385         assert(u);
 386
 387         if (u->meta.load_state == UNIT_MERGED)
 388                 return unit_active_state(unit_follow_merge(u));
 389
 390         /* After a reload it might happen that a unit is not correctly
 391          * loaded but still has a process around. That's why we won't
 392          * shortcut failed loading to UNIT_INACTIVE_FAILED. */
 393
 394         return UNIT_VTABLE(u)->active_state(u);
 395 }
 396
 397 const char* unit_sub_state_to_string(Unit *u) {
 398         assert(u);
 399
 400         return UNIT_VTABLE(u)->sub_state_to_string(u);
 401 }
 402
 403 static void complete_move(Set **s, Set **other) {
 404         assert(s);
 405         assert(other);
 406
 407         if (!*other)
 408                 return;
 409
 410         if (*s)
 411                 set_move(*s, *other);
 412         else {
 413                 *s = *other;
 414                 *other = NULL;
 415         }
 416 }
 417
 418 static void merge_names(Unit *u, Unit *other) {
 419         char *t;
 420         Iterator i;
 421
 422         assert(u);
 423         assert(other);
 424
 425         complete_move(&u->meta.names, &other->meta.names);
 426
 427         set_free_free(other->meta.names);
 428         other->meta.names = NULL;
 429         other->meta.id = NULL;
 430
 431         SET_FOREACH(t, u->meta.names, i)
 432                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 433 }
 434
 435 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 436         Iterator i;
 437         Unit *back;
 438         int r;
 439
 440         assert(u);
 441         assert(other);
 442         assert(d < _UNIT_DEPENDENCY_MAX);
 443
 444         /* Fix backwards pointers */
 445         SET_FOREACH(back, other->meta.dependencies[d], i) {
 446                 UnitDependency k;
 447
 448                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 449                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 450
 451                                 if (r == -EEXIST)
 452                                         set_remove(back->meta.dependencies[k], other);
 453                                 else
 454                                         assert(r == -ENOENT);
 455                         }
 456         }
 457
 458         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 459
 460         set_free(other->meta.dependencies[d]);
 461         other->meta.dependencies[d] = NULL;
 462 }
 463
 464 int unit_merge(Unit *u, Unit *other) {
 465         UnitDependency d;
 466
 467         assert(u);
 468         assert(other);
 469         assert(u->meta.manager == other->meta.manager);
 470         assert(u->meta.type != _UNIT_TYPE_INVALID);
 471
 472         other = unit_follow_merge(other);
 473
 474         if (other == u)
 475                 return 0;
 476
 477         if (u->meta.type != other->meta.type)
 478                 return -EINVAL;
 479
 480         if (!u->meta.instance != !other->meta.instance)
 481                 return -EINVAL;
 482
 483         if (other->meta.load_state != UNIT_STUB &&
 484             other->meta.load_state != UNIT_ERROR)
 485                 return -EEXIST;
 486
 487         if (other->meta.job)
 488                 return -EEXIST;
 489
 490         if (!UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(other)))
 491                 return -EEXIST;
 492
 493         /* Merge names */
 494         merge_names(u, other);
 495
 496         /* Merge dependencies */
 497         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 498                 merge_dependencies(u, other, d);
 499
 500         other->meta.load_state = UNIT_MERGED;
 501         other->meta.merged_into = u;
 502
 503         /* If there is still some data attached to the other node, we
 504          * don't need it anymore, and can free it. */
 505         if (other->meta.load_state != UNIT_STUB)
 506                 if (UNIT_VTABLE(other)->done)
 507                         UNIT_VTABLE(other)->done(other);
 508
 509         unit_add_to_dbus_queue(u);
 510         unit_add_to_cleanup_queue(other);
 511
 512         return 0;
 513 }
 514
 515 int unit_merge_by_name(Unit *u, const char *name) {
 516         Unit *other;
 517         int r;
 518         char *s = NULL;
 519
 520         assert(u);
 521         assert(name);
 522
 523         if (unit_name_is_template(name)) {
 524                 if (!u->meta.instance)
 525                         return -EINVAL;
 526
 527                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 528                         return -ENOMEM;
 529
 530                 name = s;
 531         }
 532
 533         if (!(other = manager_get_unit(u->meta.manager, name)))
 534                 r = unit_add_name(u, name);
 535         else
 536                 r = unit_merge(u, other);
 537
 538         free(s);
 539         return r;
 540 }
 541
 542 Unit* unit_follow_merge(Unit *u) {
 543         assert(u);
 544
 545         while (u->meta.load_state == UNIT_MERGED)
 546                 assert_se(u = u->meta.merged_into);
 547
 548         return u;
 549 }
 550
 551 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 552         int r;
 553
 554         assert(u);
 555         assert(c);
 556
 557         if (c->std_output != EXEC_OUTPUT_KMSG &&
 558             c->std_output != EXEC_OUTPUT_SYSLOG &&
 559             c->std_output != EXEC_OUTPUT_KMSG_AND_CONSOLE &&
 560             c->std_output != EXEC_OUTPUT_SYSLOG_AND_CONSOLE &&
 561             c->std_error != EXEC_OUTPUT_KMSG &&
 562             c->std_error != EXEC_OUTPUT_SYSLOG_AND_CONSOLE &&
 563             c->std_error != EXEC_OUTPUT_KMSG &&
 564             c->std_error != EXEC_OUTPUT_SYSLOG_AND_CONSOLE)
 565                 return 0;
 566
 567         /* If syslog or kernel logging is requested, make sure our own
 568          * logging daemon is run first. */
 569
 570         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 571                 return r;
 572
 573         if (u->meta.manager->running_as == MANAGER_SYSTEM)
 574                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 575                         return r;
 576
 577         return 0;
 578 }
 579
 580 const char *unit_description(Unit *u) {
 581         assert(u);
 582
 583         if (u->meta.description)
 584                 return u->meta.description;
 585
 586         return strna(u->meta.id);
 587 }
 588
 589 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 590         char *t;
 591         UnitDependency d;
 592         Iterator i;
 593         char *p2;
 594         const char *prefix2;
 595         CGroupBonding *b;
 596         char
 597                 timestamp1[FORMAT_TIMESTAMP_MAX],
 598                 timestamp2[FORMAT_TIMESTAMP_MAX],
 599                 timestamp3[FORMAT_TIMESTAMP_MAX],
 600                 timestamp4[FORMAT_TIMESTAMP_MAX],
 601                 timespan[FORMAT_TIMESPAN_MAX];
 602         Unit *following;
 603
 604         assert(u);
 605         assert(u->meta.type >= 0);
 606
 607         if (!prefix)
 608                 prefix = "";
 609         p2 = strappend(prefix, "\t");
 610         prefix2 = p2 ? p2 : prefix;
 611
 612         fprintf(f,
 613                 "%s-> Unit %s:\n"
 614                 "%s\tDescription: %s\n"
 615                 "%s\tInstance: %s\n"
 616                 "%s\tUnit Load State: %s\n"
 617                 "%s\tUnit Active State: %s\n"
 618                 "%s\tInactive Exit Timestamp: %s\n"
 619                 "%s\tActive Enter Timestamp: %s\n"
 620                 "%s\tActive Exit Timestamp: %s\n"
 621                 "%s\tInactive Enter Timestamp: %s\n"
 622                 "%s\tGC Check Good: %s\n"
 623                 "%s\tNeed Daemon Reload: %s\n",
 624                 prefix, u->meta.id,
 625                 prefix, unit_description(u),
 626                 prefix, strna(u->meta.instance),
 627                 prefix, unit_load_state_to_string(u->meta.load_state),
 628                 prefix, unit_active_state_to_string(unit_active_state(u)),
 629                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 630                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 631                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 632                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 633                 prefix, yes_no(unit_check_gc(u)),
 634                 prefix, yes_no(unit_need_daemon_reload(u)));
 635
 636         SET_FOREACH(t, u->meta.names, i)
 637                 fprintf(f, "%s\tName: %s\n", prefix, t);
 638
 639         if ((following = unit_following(u)))
 640                 fprintf(f, "%s\tFollowing: %s\n", prefix, following->meta.id);
 641
 642         if (u->meta.fragment_path)
 643                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 644
 645         if (u->meta.job_timeout > 0)
 646                 fprintf(f, "%s\tJob Timeout: %s\n", prefix, format_timespan(timespan, sizeof(timespan), u->meta.job_timeout));
 647
 648         condition_dump_list(u->meta.conditions, f, prefix);
 649
 650         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 651                 Unit *other;
 652
 653                 SET_FOREACH(other, u->meta.dependencies[d], i)
 654                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 655         }
 656
 657         if (u->meta.load_state == UNIT_LOADED) {
 658                 fprintf(f,
 659                         "%s\tStopWhenUnneeded: %s\n"
 660                         "%s\tRefuseManualStart: %s\n"
 661                         "%s\tRefuseManualStop: %s\n"
 662                         "%s\tDefaultDependencies: %s\n",
 663                         prefix, yes_no(u->meta.stop_when_unneeded),
 664                         prefix, yes_no(u->meta.refuse_manual_start),
 665                         prefix, yes_no(u->meta.refuse_manual_stop),
 666                         prefix, yes_no(u->meta.default_dependencies));
 667
 668                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 669                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 670                                 prefix, b->controller, b->path);
 671
 672                 if (UNIT_VTABLE(u)->dump)
 673                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 674
 675         } else if (u->meta.load_state == UNIT_MERGED)
 676                 fprintf(f,
 677                         "%s\tMerged into: %s\n",
 678                         prefix, u->meta.merged_into->meta.id);
 679         else if (u->meta.load_state == UNIT_ERROR)
 680                 fprintf(f, "%s\tLoad Error Code: %s\n", prefix, strerror(-u->meta.load_error));
 681
 682
 683         if (u->meta.job)
 684                 job_dump(u->meta.job, f, prefix2);
 685
 686         free(p2);
 687 }
 688
 689 /* Common implementation for multiple backends */
 690 int unit_load_fragment_and_dropin(Unit *u) {
 691         int r;
 692
 693         assert(u);
 694
 695         /* Load a .service file */
 696         if ((r = unit_load_fragment(u)) < 0)
 697                 return r;
 698
 699         if (u->meta.load_state == UNIT_STUB)
 700                 return -ENOENT;
 701
 702         /* Load drop-in directory data */
 703         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 704                 return r;
 705
 706         return 0;
 707 }
 708
 709 /* Common implementation for multiple backends */
 710 int unit_load_fragment_and_dropin_optional(Unit *u) {
 711         int r;
 712
 713         assert(u);
 714
 715         /* Same as unit_load_fragment_and_dropin(), but whether
 716          * something can be loaded or not doesn't matter. */
 717
 718         /* Load a .service file */
 719         if ((r = unit_load_fragment(u)) < 0)
 720                 return r;
 721
 722         if (u->meta.load_state == UNIT_STUB)
 723                 u->meta.load_state = UNIT_LOADED;
 724
 725         /* Load drop-in directory data */
 726         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 727                 return r;
 728
 729         return 0;
 730 }
 731
 732 int unit_add_default_target_dependency(Unit *u, Unit *target) {
 733         assert(u);
 734         assert(target);
 735
 736         if (target->meta.type != UNIT_TARGET)
 737                 return 0;
 738
 739         /* Only add the dependency if both units are loaded, so that
 740          * that loop check below is reliable */
 741         if (u->meta.load_state != UNIT_LOADED ||
 742             target->meta.load_state != UNIT_LOADED)
 743                 return 0;
 744
 745         /* If either side wants no automatic dependencies, then let's
 746          * skip this */
 747         if (!u->meta.default_dependencies ||
 748             target->meta.default_dependencies)
 749                 return 0;
 750
 751         /* Don't create loops */
 752         if (set_get(target->meta.dependencies[UNIT_BEFORE], u))
 753                 return 0;
 754
 755         return unit_add_dependency(target, UNIT_AFTER, u, true);
 756 }
 757
 758 static int unit_add_default_dependencies(Unit *u) {
 759         static const UnitDependency deps[] = {
 760                 UNIT_REQUIRED_BY,
 761                 UNIT_REQUIRED_BY_OVERRIDABLE,
 762                 UNIT_WANTED_BY,
 763                 UNIT_BOUND_BY
 764         };
 765
 766         Unit *target;
 767         Iterator i;
 768         int r;
 769         unsigned k;
 770
 771         assert(u);
 772
 773         for (k = 0; k < ELEMENTSOF(deps); k++)
 774                 SET_FOREACH(target, u->meta.dependencies[deps[k]], i)
 775                         if ((r = unit_add_default_target_dependency(u, target)) < 0)
 776                                 return r;
 777
 778         return 0;
 779 }
 780
 781 int unit_load(Unit *u) {
 782         int r;
 783
 784         assert(u);
 785
 786         if (u->meta.in_load_queue) {
 787                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 788                 u->meta.in_load_queue = false;
 789         }
 790
 791         if (u->meta.type == _UNIT_TYPE_INVALID)
 792                 return -EINVAL;
 793
 794         if (u->meta.load_state != UNIT_STUB)
 795                 return 0;
 796
 797         if (UNIT_VTABLE(u)->load)
 798                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 799                         goto fail;
 800
 801         if (u->meta.load_state == UNIT_STUB) {
 802                 r = -ENOENT;
 803                 goto fail;
 804         }
 805
 806         if (u->meta.load_state == UNIT_LOADED &&
 807             u->meta.default_dependencies)
 808                 if ((r = unit_add_default_dependencies(u)) < 0)
 809                         goto fail;
 810
 811         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 812
 813         unit_add_to_dbus_queue(unit_follow_merge(u));
 814         unit_add_to_gc_queue(u);
 815
 816         return 0;
 817
 818 fail:
 819         u->meta.load_state = UNIT_ERROR;
 820         u->meta.load_error = r;
 821         unit_add_to_dbus_queue(u);
 822
 823         log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 824
 825         return r;
 826 }
 827
 828 bool unit_condition_test(Unit *u) {
 829         assert(u);
 830
 831         dual_timestamp_get(&u->meta.condition_timestamp);
 832         u->meta.condition_result = condition_test_list(u->meta.conditions);
 833
 834         return u->meta.condition_result;
 835 }
 836
 837 /* Errors:
 838  *         -EBADR:     This unit type does not support starting.
 839  *         -EALREADY:  Unit is already started.
 840  *         -EAGAIN:    An operation is already in progress. Retry later.
 841  *         -ECANCELED: Too many requests for now.
 842  */
 843 int unit_start(Unit *u) {
 844         UnitActiveState state;
 845         Unit *following;
 846
 847         assert(u);
 848
 849         if (u->meta.load_state != UNIT_LOADED)
 850                 return -EINVAL;
 851
 852         /* If this is already (being) started, then this will
 853          * succeed. Note that this will even succeed if this unit is
 854          * not startable by the user. This is relied on to detect when
 855          * we need to wait for units and when waiting is finished. */
 856         state = unit_active_state(u);
 857         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 858                 return -EALREADY;
 859
 860         /* If the conditions failed, don't do anything at all */
 861         if (!unit_condition_test(u)) {
 862                 log_debug("Starting of %s requested but condition failed. Ignoring.", u->meta.id);
 863                 return -EALREADY;
 864         }
 865
 866         /* Forward to the main object, if we aren't it. */
 867         if ((following = unit_following(u))) {
 868                 log_debug("Redirecting start request from %s to %s.", u->meta.id, following->meta.id);
 869                 return unit_start(following);
 870         }
 871
 872         /* If it is stopped, but we cannot start it, then fail */
 873         if (!UNIT_VTABLE(u)->start)
 874                 return -EBADR;
 875
 876         /* We don't suppress calls to ->start() here when we are
 877          * already starting, to allow this request to be used as a
 878          * "hurry up" call, for example when the unit is in some "auto
 879          * restart" state where it waits for a holdoff timer to elapse
 880          * before it will start again. */
 881
 882         unit_add_to_dbus_queue(u);
 883
 884         unit_status_printf(u, "Starting %s...\n", unit_description(u));
 885         return UNIT_VTABLE(u)->start(u);
 886 }
 887
 888 bool unit_can_start(Unit *u) {
 889         assert(u);
 890
 891         return !!UNIT_VTABLE(u)->start;
 892 }
 893
 894 bool unit_can_isolate(Unit *u) {
 895         assert(u);
 896
 897         return unit_can_start(u) &&
 898                 u->meta.allow_isolate;
 899 }
 900
 901 /* Errors:
 902  *         -EBADR:    This unit type does not support stopping.
 903  *         -EALREADY: Unit is already stopped.
 904  *         -EAGAIN:   An operation is already in progress. Retry later.
 905  */
 906 int unit_stop(Unit *u) {
 907         UnitActiveState state;
 908         Unit *following;
 909
 910         assert(u);
 911
 912         state = unit_active_state(u);
 913         if (UNIT_IS_INACTIVE_OR_FAILED(state))
 914                 return -EALREADY;
 915
 916         if ((following = unit_following(u))) {
 917                 log_debug("Redirecting stop request from %s to %s.", u->meta.id, following->meta.id);
 918                 return unit_stop(following);
 919         }
 920
 921         if (!UNIT_VTABLE(u)->stop)
 922                 return -EBADR;
 923
 924         unit_add_to_dbus_queue(u);
 925
 926         unit_status_printf(u, "Stopping %s...\n", unit_description(u));
 927         return UNIT_VTABLE(u)->stop(u);
 928 }
 929
 930 /* Errors:
 931  *         -EBADR:    This unit type does not support reloading.
 932  *         -ENOEXEC:  Unit is not started.
 933  *         -EAGAIN:   An operation is already in progress. Retry later.
 934  */
 935 int unit_reload(Unit *u) {
 936         UnitActiveState state;
 937         Unit *following;
 938
 939         assert(u);
 940
 941         if (u->meta.load_state != UNIT_LOADED)
 942                 return -EINVAL;
 943
 944         if (!unit_can_reload(u))
 945                 return -EBADR;
 946
 947         state = unit_active_state(u);
 948         if (state == UNIT_RELOADING)
 949                 return -EALREADY;
 950
 951         if (state != UNIT_ACTIVE)
 952                 return -ENOEXEC;
 953
 954         if ((following = unit_following(u))) {
 955                 log_debug("Redirecting reload request from %s to %s.", u->meta.id, following->meta.id);
 956                 return unit_reload(following);
 957         }
 958
 959         unit_add_to_dbus_queue(u);
 960         return UNIT_VTABLE(u)->reload(u);
 961 }
 962
 963 bool unit_can_reload(Unit *u) {
 964         assert(u);
 965
 966         if (!UNIT_VTABLE(u)->reload)
 967                 return false;
 968
 969         if (!UNIT_VTABLE(u)->can_reload)
 970                 return true;
 971
 972         return UNIT_VTABLE(u)->can_reload(u);
 973 }
 974
 975 static void unit_check_unneeded(Unit *u) {
 976         Iterator i;
 977         Unit *other;
 978
 979         assert(u);
 980
 981         /* If this service shall be shut down when unneeded then do
 982          * so. */
 983
 984         if (!u->meta.stop_when_unneeded)
 985                 return;
 986
 987         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 988                 return;
 989
 990         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 991                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 992                         return;
 993
 994         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 995                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 996                         return;
 997
 998         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 999                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1000                         return;
1001
1002         SET_FOREACH(other, u->meta.dependencies[UNIT_BOUND_BY], i)
1003                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1004                         return;
1005
1006         log_info("Service %s is not needed anymore. Stopping.", u->meta.id);
1007
1008         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
1009         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL, NULL);
1010 }
1011
1012 static void retroactively_start_dependencies(Unit *u) {
1013         Iterator i;
1014         Unit *other;
1015
1016         assert(u);
1017         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
1018
1019         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
1020                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1021                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1022                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1023
1024         SET_FOREACH(other, u->meta.dependencies[UNIT_BIND_TO], i)
1025                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1026                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1027                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1028
1029         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1030                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1031                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1032                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
1033
1034         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
1035                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1036                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1037                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1038
1039         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
1040                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1041                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1042                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
1043
1044         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
1045                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1046                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1047
1048         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTED_BY], i)
1049                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1050                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1051 }
1052
1053 static void retroactively_stop_dependencies(Unit *u) {
1054         Iterator i;
1055         Unit *other;
1056
1057         assert(u);
1058         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
1059
1060         /* Pull down units which are bound to us recursively if enabled */
1061         SET_FOREACH(other, u->meta.dependencies[UNIT_BOUND_BY], i)
1062                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1063                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1064
1065         /* Garbage collect services that might not be needed anymore, if enabled */
1066         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
1067                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1068                         unit_check_unneeded(other);
1069         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1070                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1071                         unit_check_unneeded(other);
1072         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
1073                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1074                         unit_check_unneeded(other);
1075         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
1076                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1077                         unit_check_unneeded(other);
1078         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1079                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1080                         unit_check_unneeded(other);
1081         SET_FOREACH(other, u->meta.dependencies[UNIT_BIND_TO], i)
1082                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1083                         unit_check_unneeded(other);
1084 }
1085
1086 void unit_trigger_on_failure(Unit *u) {
1087         Unit *other;
1088         Iterator i;
1089
1090         assert(u);
1091
1092         SET_FOREACH(other, u->meta.dependencies[UNIT_ON_FAILURE], i)
1093                 manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1094 }
1095
1096 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_success) {
1097         dual_timestamp ts;
1098         bool unexpected;
1099
1100         assert(u);
1101         assert(os < _UNIT_ACTIVE_STATE_MAX);
1102         assert(ns < _UNIT_ACTIVE_STATE_MAX);
1103
1104         /* Note that this is called for all low-level state changes,
1105          * even if they might map to the same high-level
1106          * UnitActiveState! That means that ns == os is OK an expected
1107          * behaviour here. For example: if a mount point is remounted
1108          * this function will be called too! */
1109
1110         dual_timestamp_get(&ts);
1111
1112         if (UNIT_IS_INACTIVE_OR_FAILED(os) && !UNIT_IS_INACTIVE_OR_FAILED(ns))
1113                 u->meta.inactive_exit_timestamp = ts;
1114         else if (!UNIT_IS_INACTIVE_OR_FAILED(os) && UNIT_IS_INACTIVE_OR_FAILED(ns))
1115                 u->meta.inactive_enter_timestamp = ts;
1116
1117         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
1118                 u->meta.active_enter_timestamp = ts;
1119         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
1120                 u->meta.active_exit_timestamp = ts;
1121
1122         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1123                 cgroup_bonding_trim_list(u->meta.cgroup_bondings, true);
1124
1125         timer_unit_notify(u, ns);
1126         path_unit_notify(u, ns);
1127
1128         if (u->meta.job) {
1129                 unexpected = false;
1130
1131                 if (u->meta.job->state == JOB_WAITING)
1132
1133                         /* So we reached a different state for this
1134                          * job. Let's see if we can run it now if it
1135                          * failed previously due to EAGAIN. */
1136                         job_add_to_run_queue(u->meta.job);
1137
1138                 /* Let's check whether this state change constitutes a
1139                  * finished job, or maybe contradicts a running job and
1140                  * hence needs to invalidate jobs. */
1141
1142                 switch (u->meta.job->type) {
1143
1144                 case JOB_START:
1145                 case JOB_VERIFY_ACTIVE:
1146
1147                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
1148                                 job_finish_and_invalidate(u->meta.job, JOB_DONE);
1149                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
1150                                 unexpected = true;
1151
1152                                 if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1153                                         job_finish_and_invalidate(u->meta.job, ns == UNIT_FAILED ? JOB_FAILED : JOB_DONE);
1154                         }
1155
1156                         break;
1157
1158                 case JOB_RELOAD:
1159                 case JOB_RELOAD_OR_START:
1160
1161                         if (u->meta.job->state == JOB_RUNNING) {
1162                                 if (ns == UNIT_ACTIVE)
1163                                         job_finish_and_invalidate(u->meta.job, reload_success ? JOB_DONE : JOB_FAILED);
1164                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
1165                                         unexpected = true;
1166
1167                                         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1168                                                 job_finish_and_invalidate(u->meta.job, ns == UNIT_FAILED ? JOB_FAILED : JOB_DONE);
1169                                 }
1170                         }
1171
1172                         break;
1173
1174                 case JOB_STOP:
1175                 case JOB_RESTART:
1176                 case JOB_TRY_RESTART:
1177
1178                         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1179                                 job_finish_and_invalidate(u->meta.job, JOB_DONE);
1180                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1181                                 unexpected = true;
1182                                 job_finish_and_invalidate(u->meta.job, JOB_FAILED);
1183                         }
1184
1185                         break;
1186
1187                 default:
1188                         assert_not_reached("Job type unknown");
1189                 }
1190
1191         } else
1192                 unexpected = true;
1193
1194         /* If this state change happened without being requested by a
1195          * job, then let's retroactively start or stop
1196          * dependencies. We skip that step when deserializing, since
1197          * we don't want to create any additional jobs just because
1198          * something is already activated. */
1199
1200         if (unexpected && u->meta.manager->n_deserializing <= 0) {
1201                 if (UNIT_IS_INACTIVE_OR_FAILED(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1202                         retroactively_start_dependencies(u);
1203                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1204                         retroactively_stop_dependencies(u);
1205         }
1206
1207         if (ns != os && ns == UNIT_FAILED) {
1208                 log_notice("Unit %s entered failed state.", u->meta.id);
1209                 unit_trigger_on_failure(u);
1210         }
1211
1212         /* Some names are special */
1213         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1214                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE))
1215                         /* The bus just might have become available,
1216                          * hence try to connect to it, if we aren't
1217                          * yet connected. */
1218                         bus_init(u->meta.manager, true);
1219
1220                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1221                         /* The syslog daemon just might have become
1222                          * available, hence try to connect to it, if
1223                          * we aren't yet connected. */
1224                         log_open();
1225
1226                 if (u->meta.type == UNIT_SERVICE &&
1227                     !UNIT_IS_ACTIVE_OR_RELOADING(os)) {
1228                         /* Write audit record if we have just finished starting up */
1229                         manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_START, true);
1230                         u->meta.in_audit = true;
1231                 }
1232
1233                 if (!UNIT_IS_ACTIVE_OR_RELOADING(os))
1234                         manager_send_unit_plymouth(u->meta.manager, u);
1235
1236         } else {
1237
1238                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1239                         /* The syslog daemon might just have
1240                          * terminated, hence try to disconnect from
1241                          * it. */
1242                         log_close_syslog();
1243
1244                 /* We don't care about D-Bus here, since we'll get an
1245                  * asynchronous notification for it anyway. */
1246
1247                 if (u->meta.type == UNIT_SERVICE &&
1248                     UNIT_IS_INACTIVE_OR_FAILED(ns) &&
1249                     !UNIT_IS_INACTIVE_OR_FAILED(os)) {
1250
1251                         /* Hmm, if there was no start record written
1252                          * write it now, so that we always have a nice
1253                          * pair */
1254                         if (!u->meta.in_audit) {
1255                                 manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_START, ns == UNIT_INACTIVE);
1256
1257                                 if (ns == UNIT_INACTIVE)
1258                                         manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_STOP, true);
1259                         } else
1260                                 /* Write audit record if we have just finished shutting down */
1261                                 manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_STOP, ns == UNIT_INACTIVE);
1262
1263                         u->meta.in_audit = false;
1264                 }
1265         }
1266
1267         /* Maybe we finished startup and are now ready for being
1268          * stopped because unneeded? */
1269         unit_check_unneeded(u);
1270
1271         unit_add_to_dbus_queue(u);
1272         unit_add_to_gc_queue(u);
1273 }
1274
1275 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1276         struct epoll_event ev;
1277
1278         assert(u);
1279         assert(fd >= 0);
1280         assert(w);
1281         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1282
1283         zero(ev);
1284         ev.data.ptr = w;
1285         ev.events = events;
1286
1287         if (epoll_ctl(u->meta.manager->epoll_fd,
1288                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1289                       fd,
1290                       &ev) < 0)
1291                 return -errno;
1292
1293         w->fd = fd;
1294         w->type = WATCH_FD;
1295         w->data.unit = u;
1296
1297         return 0;
1298 }
1299
1300 void unit_unwatch_fd(Unit *u, Watch *w) {
1301         assert(u);
1302         assert(w);
1303
1304         if (w->type == WATCH_INVALID)
1305                 return;
1306
1307         assert(w->type == WATCH_FD);
1308         assert(w->data.unit == u);
1309         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1310
1311         w->fd = -1;
1312         w->type = WATCH_INVALID;
1313         w->data.unit = NULL;
1314 }
1315
1316 int unit_watch_pid(Unit *u, pid_t pid) {
1317         assert(u);
1318         assert(pid >= 1);
1319
1320         /* Watch a specific PID. We only support one unit watching
1321          * each PID for now. */
1322
1323         return hashmap_put(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1324 }
1325
1326 void unit_unwatch_pid(Unit *u, pid_t pid) {
1327         assert(u);
1328         assert(pid >= 1);
1329
1330         hashmap_remove_value(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1331 }
1332
1333 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1334         struct itimerspec its;
1335         int flags, fd;
1336         bool ours;
1337
1338         assert(u);
1339         assert(w);
1340         assert(w->type == WATCH_INVALID || (w->type == WATCH_UNIT_TIMER && w->data.unit == u));
1341
1342         /* This will try to reuse the old timer if there is one */
1343
1344         if (w->type == WATCH_UNIT_TIMER) {
1345                 assert(w->data.unit == u);
1346                 assert(w->fd >= 0);
1347
1348                 ours = false;
1349                 fd = w->fd;
1350         } else if (w->type == WATCH_INVALID) {
1351
1352                 ours = true;
1353                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1354                         return -errno;
1355         } else
1356                 assert_not_reached("Invalid watch type");
1357
1358         zero(its);
1359
1360         if (delay <= 0) {
1361                 /* Set absolute time in the past, but not 0, since we
1362                  * don't want to disarm the timer */
1363                 its.it_value.tv_sec = 0;
1364                 its.it_value.tv_nsec = 1;
1365
1366                 flags = TFD_TIMER_ABSTIME;
1367         } else {
1368                 timespec_store(&its.it_value, delay);
1369                 flags = 0;
1370         }
1371
1372         /* This will also flush the elapse counter */
1373         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1374                 goto fail;
1375
1376         if (w->type == WATCH_INVALID) {
1377                 struct epoll_event ev;
1378
1379                 zero(ev);
1380                 ev.data.ptr = w;
1381                 ev.events = EPOLLIN;
1382
1383                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1384                         goto fail;
1385         }
1386
1387         w->type = WATCH_UNIT_TIMER;
1388         w->fd = fd;
1389         w->data.unit = u;
1390
1391         return 0;
1392
1393 fail:
1394         if (ours)
1395                 close_nointr_nofail(fd);
1396
1397         return -errno;
1398 }
1399
1400 void unit_unwatch_timer(Unit *u, Watch *w) {
1401         assert(u);
1402         assert(w);
1403
1404         if (w->type == WATCH_INVALID)
1405                 return;
1406
1407         assert(w->type == WATCH_UNIT_TIMER);
1408         assert(w->data.unit == u);
1409         assert(w->fd >= 0);
1410
1411         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1412         close_nointr_nofail(w->fd);
1413
1414         w->fd = -1;
1415         w->type = WATCH_INVALID;
1416         w->data.unit = NULL;
1417 }
1418
1419 bool unit_job_is_applicable(Unit *u, JobType j) {
1420         assert(u);
1421         assert(j >= 0 && j < _JOB_TYPE_MAX);
1422
1423         switch (j) {
1424
1425         case JOB_VERIFY_ACTIVE:
1426         case JOB_START:
1427         case JOB_STOP:
1428                 return true;
1429
1430         case JOB_RESTART:
1431         case JOB_TRY_RESTART:
1432                 return unit_can_start(u);
1433
1434         case JOB_RELOAD:
1435                 return unit_can_reload(u);
1436
1437         case JOB_RELOAD_OR_START:
1438                 return unit_can_reload(u) && unit_can_start(u);
1439
1440         default:
1441                 assert_not_reached("Invalid job type");
1442         }
1443 }
1444
1445 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1446
1447         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1448                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1449                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1450                 [UNIT_WANTS] = UNIT_WANTED_BY,
1451                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1452                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1453                 [UNIT_BIND_TO] = UNIT_BOUND_BY,
1454                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1455                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1456                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1457                 [UNIT_BOUND_BY] = UNIT_BIND_TO,
1458                 [UNIT_CONFLICTS] = UNIT_CONFLICTED_BY,
1459                 [UNIT_CONFLICTED_BY] = UNIT_CONFLICTS,
1460                 [UNIT_BEFORE] = UNIT_AFTER,
1461                 [UNIT_AFTER] = UNIT_BEFORE,
1462                 [UNIT_ON_FAILURE] = _UNIT_DEPENDENCY_INVALID,
1463                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1464                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1465         };
1466         int r, q = 0, v = 0, w = 0;
1467
1468         assert(u);
1469         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1470         assert(other);
1471
1472         u = unit_follow_merge(u);
1473         other = unit_follow_merge(other);
1474
1475         /* We won't allow dependencies on ourselves. We will not
1476          * consider them an error however. */
1477         if (u == other)
1478                 return 0;
1479
1480         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0)
1481                 return r;
1482
1483         if (inverse_table[d] != _UNIT_DEPENDENCY_INVALID)
1484                 if ((r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1485                         return r;
1486
1487         if (add_reference)
1488                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1489                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1490                         return r;
1491
1492         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1493                 return q;
1494
1495         if (inverse_table[d] != _UNIT_DEPENDENCY_INVALID)
1496                 if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1497                         r = v;
1498                         goto fail;
1499                 }
1500
1501         if (add_reference) {
1502                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1503                         r = w;
1504                         goto fail;
1505                 }
1506
1507                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1508                         goto fail;
1509         }
1510
1511         unit_add_to_dbus_queue(u);
1512         return 0;
1513
1514 fail:
1515         if (q > 0)
1516                 set_remove(u->meta.dependencies[d], other);
1517
1518         if (v > 0)
1519                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1520
1521         if (w > 0)
1522                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1523
1524         return r;
1525 }
1526
1527 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference) {
1528         int r;
1529
1530         assert(u);
1531
1532         if ((r = unit_add_dependency(u, d, other, add_reference)) < 0)
1533                 return r;
1534
1535         if ((r = unit_add_dependency(u, e, other, add_reference)) < 0)
1536                 return r;
1537
1538         return 0;
1539 }
1540
1541 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1542         char *s;
1543
1544         assert(u);
1545         assert(name || path);
1546
1547         if (!name)
1548                 name = file_name_from_path(path);
1549
1550         if (!unit_name_is_template(name)) {
1551                 *p = NULL;
1552                 return name;
1553         }
1554
1555         if (u->meta.instance)
1556                 s = unit_name_replace_instance(name, u->meta.instance);
1557         else {
1558                 char *i;
1559
1560                 if (!(i = unit_name_to_prefix(u->meta.id)))
1561                         return NULL;
1562
1563                 s = unit_name_replace_instance(name, i);
1564                 free(i);
1565         }
1566
1567         if (!s)
1568                 return NULL;
1569
1570         *p = s;
1571         return s;
1572 }
1573
1574 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1575         Unit *other;
1576         int r;
1577         char *s;
1578
1579         assert(u);
1580         assert(name || path);
1581
1582         if (!(name = resolve_template(u, name, path, &s)))
1583                 return -ENOMEM;
1584
1585         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1586                 goto finish;
1587
1588         r = unit_add_dependency(u, d, other, add_reference);
1589
1590 finish:
1591         free(s);
1592         return r;
1593 }
1594
1595 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1596         Unit *other;
1597         int r;
1598         char *s;
1599
1600         assert(u);
1601         assert(name || path);
1602
1603         if (!(name = resolve_template(u, name, path, &s)))
1604                 return -ENOMEM;
1605
1606         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1607                 goto finish;
1608
1609         r = unit_add_two_dependencies(u, d, e, other, add_reference);
1610
1611 finish:
1612         free(s);
1613         return r;
1614 }
1615
1616 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1617         Unit *other;
1618         int r;
1619         char *s;
1620
1621         assert(u);
1622         assert(name || path);
1623
1624         if (!(name = resolve_template(u, name, path, &s)))
1625                 return -ENOMEM;
1626
1627         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1628                 goto finish;
1629
1630         r = unit_add_dependency(other, d, u, add_reference);
1631
1632 finish:
1633         free(s);
1634         return r;
1635 }
1636
1637 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1638         Unit *other;
1639         int r;
1640         char *s;
1641
1642         assert(u);
1643         assert(name || path);
1644
1645         if (!(name = resolve_template(u, name, path, &s)))
1646                 return -ENOMEM;
1647
1648         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1649                 goto finish;
1650
1651         if ((r = unit_add_two_dependencies(other, d, e, u, add_reference)) < 0)
1652                 goto finish;
1653
1654 finish:
1655         free(s);
1656         return r;
1657 }
1658
1659 int set_unit_path(const char *p) {
1660         char *cwd, *c;
1661         int r;
1662
1663         /* This is mostly for debug purposes */
1664
1665         if (path_is_absolute(p)) {
1666                 if (!(c = strdup(p)))
1667                         return -ENOMEM;
1668         } else {
1669                 if (!(cwd = get_current_dir_name()))
1670                         return -errno;
1671
1672                 r = asprintf(&c, "%s/%s", cwd, p);
1673                 free(cwd);
1674
1675                 if (r < 0)
1676                         return -ENOMEM;
1677         }
1678
1679         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1680                 r = -errno;
1681                 free(c);
1682                 return r;
1683         }
1684
1685         return 0;
1686 }
1687
1688 char *unit_dbus_path(Unit *u) {
1689         char *p, *e;
1690
1691         assert(u);
1692
1693         if (!u->meta.id)
1694                 return NULL;
1695
1696         if (!(e = bus_path_escape(u->meta.id)))
1697                 return NULL;
1698
1699         p = strappend("/org/freedesktop/systemd1/unit/", e);
1700         free(e);
1701
1702         return p;
1703 }
1704
1705 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1706         int r;
1707
1708         assert(u);
1709         assert(b);
1710
1711         assert(b->path);
1712
1713         if (!b->controller)
1714                 if (!(b->controller = strdup(SYSTEMD_CGROUP_CONTROLLER)))
1715                         return -ENOMEM;
1716
1717         /* Ensure this hasn't been added yet */
1718         assert(!b->unit);
1719
1720         if (streq(b->controller, SYSTEMD_CGROUP_CONTROLLER)) {
1721                 CGroupBonding *l;
1722
1723                 l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1724                 LIST_PREPEND(CGroupBonding, by_path, l, b);
1725
1726                 if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1727                         LIST_REMOVE(CGroupBonding, by_path, l, b);
1728                         return r;
1729                 }
1730         }
1731
1732         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1733         b->unit = u;
1734
1735         return 0;
1736 }
1737
1738 static char *default_cgroup_path(Unit *u) {
1739         char *p;
1740         int r;
1741
1742         assert(u);
1743
1744         if (u->meta.instance) {
1745                 char *t;
1746
1747                 if (!(t = unit_name_template(u->meta.id)))
1748                         return NULL;
1749
1750                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1751                 free(t);
1752         } else
1753                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1754
1755         return r < 0 ? NULL : p;
1756 }
1757
1758 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1759         char *controller = NULL, *path = NULL;
1760         CGroupBonding *b = NULL;
1761         int r;
1762
1763         assert(u);
1764         assert(name);
1765
1766         if ((r = cg_split_spec(name, &controller, &path)) < 0)
1767                 return r;
1768
1769         if (!path)
1770                 path = default_cgroup_path(u);
1771
1772         if (!controller)
1773                 controller = strdup(SYSTEMD_CGROUP_CONTROLLER);
1774
1775         if (!path || !controller) {
1776                 free(path);
1777                 free(controller);
1778
1779                 return -ENOMEM;
1780         }
1781
1782         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1783                 r = -EEXIST;
1784                 goto fail;
1785         }
1786
1787         if (!(b = new0(CGroupBonding, 1))) {
1788                 r = -ENOMEM;
1789                 goto fail;
1790         }
1791
1792         b->controller = controller;
1793         b->path = path;
1794         b->ours = false;
1795
1796         if ((r = unit_add_cgroup(u, b)) < 0)
1797                 goto fail;
1798
1799         return 0;
1800
1801 fail:
1802         free(path);
1803         free(controller);
1804         free(b);
1805
1806         return r;
1807 }
1808
1809 static int unit_add_one_default_cgroup(Unit *u, const char *controller) {
1810         CGroupBonding *b = NULL;
1811         int r = -ENOMEM;
1812
1813         assert(u);
1814
1815         if (!controller)
1816                 controller = SYSTEMD_CGROUP_CONTROLLER;
1817
1818         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller))
1819                 return 0;
1820
1821         if (!(b = new0(CGroupBonding, 1)))
1822                 return -ENOMEM;
1823
1824         if (!(b->controller = strdup(controller)))
1825                 goto fail;
1826
1827         if (!(b->path = default_cgroup_path(u)))
1828                 goto fail;
1829
1830         b->ours = true;
1831         b->essential = streq(controller, SYSTEMD_CGROUP_CONTROLLER);
1832
1833         if ((r = unit_add_cgroup(u, b)) < 0)
1834                 goto fail;
1835
1836         return 0;
1837
1838 fail:
1839         free(b->path);
1840         free(b->controller);
1841         free(b);
1842
1843         return r;
1844 }
1845
1846 int unit_add_default_cgroups(Unit *u) {
1847         char **c;
1848         int r;
1849         assert(u);
1850
1851         /* Adds in the default cgroups, if they weren't specified
1852          * otherwise. */
1853
1854         if ((r = unit_add_one_default_cgroup(u, NULL)) < 0)
1855                 return r;
1856
1857         STRV_FOREACH(c, u->meta.manager->default_controllers)
1858                 if ((r = unit_add_one_default_cgroup(u, *c)) < 0)
1859                         return r;
1860
1861         return 0;
1862 }
1863
1864 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1865         assert(u);
1866
1867         return cgroup_bonding_find_list(u->meta.cgroup_bondings, SYSTEMD_CGROUP_CONTROLLER);
1868 }
1869
1870 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1871         char *t;
1872         int r;
1873
1874         assert(u);
1875         assert(type);
1876         assert(_found);
1877
1878         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1879                 return -ENOMEM;
1880
1881         assert(!unit_has_name(u, t));
1882
1883         r = manager_load_unit(u->meta.manager, t, NULL, NULL, _found);
1884         free(t);
1885
1886         assert(r < 0 || *_found != u);
1887
1888         return r;
1889 }
1890
1891 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1892         Unit *found;
1893         char *t;
1894
1895         assert(u);
1896         assert(type);
1897         assert(_found);
1898
1899         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1900                 return -ENOMEM;
1901
1902         assert(!unit_has_name(u, t));
1903
1904         found = manager_get_unit(u->meta.manager, t);
1905         free(t);
1906
1907         if (!found)
1908                 return -ENOENT;
1909
1910         *_found = found;
1911         return 0;
1912 }
1913
1914 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1915         Unit *u = userdata;
1916         assert(u);
1917
1918         return unit_name_to_prefix_and_instance(u->meta.id);
1919 }
1920
1921 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1922         Unit *u = userdata;
1923         assert(u);
1924
1925         return unit_name_to_prefix(u->meta.id);
1926 }
1927
1928 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1929         Unit *u = userdata;
1930         char *p, *r;
1931
1932         assert(u);
1933
1934         if (!(p = unit_name_to_prefix(u->meta.id)))
1935                 return NULL;
1936
1937         r = unit_name_unescape(p);
1938         free(p);
1939
1940         return r;
1941 }
1942
1943 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1944         Unit *u = userdata;
1945         assert(u);
1946
1947         if (u->meta.instance)
1948                 return unit_name_unescape(u->meta.instance);
1949
1950         return strdup("");
1951 }
1952
1953 static char *specifier_filename(char specifier, void *data, void *userdata) {
1954         Unit *u = userdata;
1955         assert(u);
1956
1957         if (u->meta.instance)
1958                 return unit_name_path_unescape(u->meta.instance);
1959
1960         return unit_name_to_path(u->meta.instance);
1961 }
1962
1963 char *unit_name_printf(Unit *u, const char* format) {
1964
1965         /*
1966          * This will use the passed string as format string and
1967          * replace the following specifiers:
1968          *
1969          * %n: the full id of the unit                 (foo@bar.waldo)
1970          * %N: the id of the unit without the suffix   (foo@bar)
1971          * %p: the prefix                              (foo)
1972          * %i: the instance                            (bar)
1973          */
1974
1975         const Specifier table[] = {
1976                 { 'n', specifier_string,              u->meta.id },
1977                 { 'N', specifier_prefix_and_instance, NULL },
1978                 { 'p', specifier_prefix,              NULL },
1979                 { 'i', specifier_string,              u->meta.instance },
1980                 { 0, NULL, NULL }
1981         };
1982
1983         assert(u);
1984         assert(format);
1985
1986         return specifier_printf(format, table, u);
1987 }
1988
1989 char *unit_full_printf(Unit *u, const char *format) {
1990
1991         /* This is similar to unit_name_printf() but also supports
1992          * unescaping */
1993
1994         const Specifier table[] = {
1995                 { 'n', specifier_string,              u->meta.id },
1996                 { 'N', specifier_prefix_and_instance, NULL },
1997                 { 'p', specifier_prefix,              NULL },
1998                 { 'P', specifier_prefix_unescaped,    NULL },
1999                 { 'i', specifier_string,              u->meta.instance },
2000                 { 'I', specifier_instance_unescaped,  NULL },
2001                 { 'f', specifier_filename,            NULL },
2002                 { 0, NULL, NULL }
2003         };
2004
2005         assert(u);
2006         assert(format);
2007
2008         return specifier_printf(format, table, u);
2009 }
2010
2011 char **unit_full_printf_strv(Unit *u, char **l) {
2012         size_t n;
2013         char **r, **i, **j;
2014
2015         /* Applies unit_full_printf to every entry in l */
2016
2017         assert(u);
2018
2019         n = strv_length(l);
2020         if (!(r = new(char*, n+1)))
2021                 return NULL;
2022
2023         for (i = l, j = r; *i; i++, j++)
2024                 if (!(*j = unit_full_printf(u, *i)))
2025                         goto fail;
2026
2027         *j = NULL;
2028         return r;
2029
2030 fail:
2031         j--;
2032         while (j >= r)
2033                 free(*j);
2034
2035         free(r);
2036
2037         return NULL;
2038 }
2039
2040 int unit_watch_bus_name(Unit *u, const char *name) {
2041         assert(u);
2042         assert(name);
2043
2044         /* Watch a specific name on the bus. We only support one unit
2045          * watching each name for now. */
2046
2047         return hashmap_put(u->meta.manager->watch_bus, name, u);
2048 }
2049
2050 void unit_unwatch_bus_name(Unit *u, const char *name) {
2051         assert(u);
2052         assert(name);
2053
2054         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
2055 }
2056
2057 bool unit_can_serialize(Unit *u) {
2058         assert(u);
2059
2060         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
2061 }
2062
2063 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
2064         int r;
2065
2066         assert(u);
2067         assert(f);
2068         assert(fds);
2069
2070         if (!unit_can_serialize(u))
2071                 return 0;
2072
2073         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
2074                 return r;
2075
2076         if (u->meta.job)
2077                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
2078
2079         dual_timestamp_serialize(f, "inactive-exit-timestamp", &u->meta.inactive_exit_timestamp);
2080         dual_timestamp_serialize(f, "active-enter-timestamp", &u->meta.active_enter_timestamp);
2081         dual_timestamp_serialize(f, "active-exit-timestamp", &u->meta.active_exit_timestamp);
2082         dual_timestamp_serialize(f, "inactive-enter-timestamp", &u->meta.inactive_enter_timestamp);
2083
2084         /* End marker */
2085         fputc('\n', f);
2086         return 0;
2087 }
2088
2089 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
2090         va_list ap;
2091
2092         assert(u);
2093         assert(f);
2094         assert(key);
2095         assert(format);
2096
2097         fputs(key, f);
2098         fputc('=', f);
2099
2100         va_start(ap, format);
2101         vfprintf(f, format, ap);
2102         va_end(ap);
2103
2104         fputc('\n', f);
2105 }
2106
2107 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
2108         assert(u);
2109         assert(f);
2110         assert(key);
2111         assert(value);
2112
2113         fprintf(f, "%s=%s\n", key, value);
2114 }
2115
2116 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
2117         int r;
2118
2119         assert(u);
2120         assert(f);
2121         assert(fds);
2122
2123         if (!unit_can_serialize(u))
2124                 return 0;
2125
2126         for (;;) {
2127                 char line[1024], *l, *v;
2128                 size_t k;
2129
2130                 if (!fgets(line, sizeof(line), f)) {
2131                         if (feof(f))
2132                                 return 0;
2133                         return -errno;
2134                 }
2135
2136                 char_array_0(line);
2137                 l = strstrip(line);
2138
2139                 /* End marker */
2140                 if (l[0] == 0)
2141                         return 0;
2142
2143                 k = strcspn(l, "=");
2144
2145                 if (l[k] == '=') {
2146                         l[k] = 0;
2147                         v = l+k+1;
2148                 } else
2149                         v = l+k;
2150
2151                 if (streq(l, "job")) {
2152                         JobType type;
2153
2154                         if ((type = job_type_from_string(v)) < 0)
2155                                 log_debug("Failed to parse job type value %s", v);
2156                         else
2157                                 u->meta.deserialized_job = type;
2158
2159                         continue;
2160                 } else if (streq(l, "inactive-exit-timestamp")) {
2161                         dual_timestamp_deserialize(v, &u->meta.inactive_exit_timestamp);
2162                         continue;
2163                 } else if (streq(l, "active-enter-timestamp")) {
2164                         dual_timestamp_deserialize(v, &u->meta.active_enter_timestamp);
2165                         continue;
2166                 } else if (streq(l, "active-exit-timestamp")) {
2167                         dual_timestamp_deserialize(v, &u->meta.active_exit_timestamp);
2168                         continue;
2169                 } else if (streq(l, "inactive-enter-timestamp")) {
2170                         dual_timestamp_deserialize(v, &u->meta.inactive_enter_timestamp);
2171                         continue;
2172                 }
2173
2174                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
2175                         return r;
2176         }
2177 }
2178
2179 int unit_add_node_link(Unit *u, const char *what, bool wants) {
2180         Unit *device;
2181         char *e;
2182         int r;
2183
2184         assert(u);
2185
2186         if (!what)
2187                 return 0;
2188
2189         /* Adds in links to the device node that this unit is based on */
2190
2191         if (!is_device_path(what))
2192                 return 0;
2193
2194         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
2195                 return -ENOMEM;
2196
2197         r = manager_load_unit(u->meta.manager, e, NULL, NULL, &device);
2198         free(e);
2199
2200         if (r < 0)
2201                 return r;
2202
2203         if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_BIND_TO, device, true)) < 0)
2204                 return r;
2205
2206         if (wants)
2207                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
2208                         return r;
2209
2210         return 0;
2211 }
2212
2213 int unit_coldplug(Unit *u) {
2214         int r;
2215
2216         assert(u);
2217
2218         if (UNIT_VTABLE(u)->coldplug)
2219                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
2220                         return r;
2221
2222         if (u->meta.deserialized_job >= 0) {
2223                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL, NULL)) < 0)
2224                         return r;
2225
2226                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
2227         }
2228
2229         return 0;
2230 }
2231
2232 void unit_status_printf(Unit *u, const char *format, ...) {
2233         va_list ap;
2234
2235         assert(u);
2236         assert(format);
2237
2238         if (!UNIT_VTABLE(u)->show_status)
2239                 return;
2240
2241         if (u->meta.manager->running_as != MANAGER_SYSTEM)
2242                 return;
2243
2244         if (!u->meta.manager->show_status)
2245                 return;
2246
2247         if (!manager_is_booting_or_shutting_down(u->meta.manager))
2248                 return;
2249
2250         va_start(ap, format);
2251         status_vprintf(format, ap);
2252         va_end(ap);
2253 }
2254
2255 bool unit_need_daemon_reload(Unit *u) {
2256         struct stat st;
2257
2258         assert(u);
2259
2260         if (!u->meta.fragment_path)
2261                 return false;
2262
2263         zero(st);
2264         if (stat(u->meta.fragment_path, &st) < 0)
2265                 /* What, cannot access this anymore? */
2266                 return true;
2267
2268         return
2269                 u->meta.fragment_mtime &&
2270                 timespec_load(&st.st_mtim) != u->meta.fragment_mtime;
2271 }
2272
2273 void unit_reset_failed(Unit *u) {
2274         assert(u);
2275
2276         if (UNIT_VTABLE(u)->reset_failed)
2277                 UNIT_VTABLE(u)->reset_failed(u);
2278 }
2279
2280 Unit *unit_following(Unit *u) {
2281         assert(u);
2282
2283         if (UNIT_VTABLE(u)->following)
2284                 return UNIT_VTABLE(u)->following(u);
2285
2286         return NULL;
2287 }
2288
2289 bool unit_pending_inactive(Unit *u) {
2290         assert(u);
2291
2292         /* Returns true if the unit is inactive or going down */
2293
2294         if (UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)))
2295                 return true;
2296
2297         if (u->meta.job && u->meta.job->type == JOB_STOP)
2298                 return true;
2299
2300         return false;
2301 }
2302
2303 bool unit_pending_active(Unit *u) {
2304         assert(u);
2305
2306         /* Returns true if the unit is inactive or going down */
2307
2308         if (UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
2309                 return true;
2310
2311         if (u->meta.job &&
2312             (u->meta.job->type == JOB_START ||
2313              u->meta.job->type == JOB_RELOAD_OR_START ||
2314              u->meta.job->type == JOB_RESTART))
2315                 return true;
2316
2317         return false;
2318 }
2319
2320 UnitType unit_name_to_type(const char *n) {
2321         UnitType t;
2322
2323         assert(n);
2324
2325         for (t = 0; t < _UNIT_TYPE_MAX; t++)
2326                 if (endswith(n, unit_vtable[t]->suffix))
2327                         return t;
2328
2329         return _UNIT_TYPE_INVALID;
2330 }
2331
2332 bool unit_name_is_valid(const char *n, bool template_ok) {
2333         UnitType t;
2334
2335         t = unit_name_to_type(n);
2336         if (t < 0 || t >= _UNIT_TYPE_MAX)
2337                 return false;
2338
2339         return unit_name_is_valid_no_type(n, template_ok);
2340 }
2341
2342 int unit_kill(Unit *u, KillWho w, KillMode m, int signo, DBusError *error) {
2343         assert(u);
2344         assert(w >= 0 && w < _KILL_WHO_MAX);
2345         assert(m >= 0 && m < _KILL_MODE_MAX);
2346         assert(signo > 0);
2347         assert(signo < _NSIG);
2348
2349         if (m == KILL_NONE)
2350                 return 0;
2351
2352         if (!UNIT_VTABLE(u)->kill)
2353                 return -ENOTSUP;
2354
2355         return UNIT_VTABLE(u)->kill(u, w, m, signo, error);
2356 }
2357
2358
2359 int unit_following_set(Unit *u, Set **s) {
2360         assert(u);
2361         assert(s);
2362
2363         if (UNIT_VTABLE(u)->following_set)
2364                 return UNIT_VTABLE(u)->following_set(u, s);
2365
2366         *s = NULL;
2367         return 0;
2368 }
2369
2370 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
2371         [UNIT_STUB] = "stub",
2372         [UNIT_LOADED] = "loaded",
2373         [UNIT_ERROR] = "error",
2374         [UNIT_MERGED] = "merged",
2375         [UNIT_MASKED] = "masked"
2376 };
2377
2378 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
2379
2380 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
2381         [UNIT_ACTIVE] = "active",
2382         [UNIT_RELOADING] = "reloading",
2383         [UNIT_INACTIVE] = "inactive",
2384         [UNIT_FAILED] = "failed",
2385         [UNIT_ACTIVATING] = "activating",
2386         [UNIT_DEACTIVATING] = "deactivating"
2387 };
2388
2389 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
2390
2391 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
2392         [UNIT_REQUIRES] = "Requires",
2393         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
2394         [UNIT_WANTS] = "Wants",
2395         [UNIT_REQUISITE] = "Requisite",
2396         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
2397         [UNIT_REQUIRED_BY] = "RequiredBy",
2398         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
2399         [UNIT_BIND_TO] = "BindTo",
2400         [UNIT_WANTED_BY] = "WantedBy",
2401         [UNIT_CONFLICTS] = "Conflicts",
2402         [UNIT_CONFLICTED_BY] = "ConflictedBy",
2403         [UNIT_BOUND_BY] = "BoundBy",
2404         [UNIT_BEFORE] = "Before",
2405         [UNIT_AFTER] = "After",
2406         [UNIT_REFERENCES] = "References",
2407         [UNIT_REFERENCED_BY] = "ReferencedBy",
2408         [UNIT_ON_FAILURE] = "OnFailure"
2409 };
2410
2411 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);