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         /* Don't create loops */
 746         if (set_get(target->meta.dependencies[UNIT_BEFORE], u))
 747                 return 0;
 748
 749         return unit_add_dependency(target, UNIT_AFTER, u, true);
 750 }
 751
 752 static int unit_add_default_dependencies(Unit *u) {
 753         Unit *target;
 754         Iterator i;
 755         int r;
 756
 757         assert(u);
 758
 759         SET_FOREACH(target, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 760                 if ((r = unit_add_default_target_dependency(u, target)) < 0)
 761                         return r;
 762
 763         SET_FOREACH(target, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 764                 if ((r = unit_add_default_target_dependency(u, target)) < 0)
 765                         return r;
 766
 767         SET_FOREACH(target, u->meta.dependencies[UNIT_WANTED_BY], i)
 768                 if ((r = unit_add_default_target_dependency(u, target)) < 0)
 769                         return r;
 770
 771         SET_FOREACH(target, u->meta.dependencies[UNIT_BOUND_BY], i)
 772                 if ((r = unit_add_default_target_dependency(u, target)) < 0)
 773                         return r;
 774
 775         return 0;
 776 }
 777
 778 int unit_load(Unit *u) {
 779         int r;
 780
 781         assert(u);
 782
 783         if (u->meta.in_load_queue) {
 784                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 785                 u->meta.in_load_queue = false;
 786         }
 787
 788         if (u->meta.type == _UNIT_TYPE_INVALID)
 789                 return -EINVAL;
 790
 791         if (u->meta.load_state != UNIT_STUB)
 792                 return 0;
 793
 794         if (UNIT_VTABLE(u)->load)
 795                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 796                         goto fail;
 797
 798         if (u->meta.load_state == UNIT_STUB) {
 799                 r = -ENOENT;
 800                 goto fail;
 801         }
 802
 803         if (u->meta.load_state == UNIT_LOADED &&
 804             u->meta.default_dependencies)
 805                 if ((r = unit_add_default_dependencies(u)) < 0)
 806                         goto fail;
 807
 808         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 809
 810         unit_add_to_dbus_queue(unit_follow_merge(u));
 811         unit_add_to_gc_queue(u);
 812
 813         return 0;
 814
 815 fail:
 816         u->meta.load_state = UNIT_ERROR;
 817         u->meta.load_error = r;
 818         unit_add_to_dbus_queue(u);
 819
 820         log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 821
 822         return r;
 823 }
 824
 825 /* Errors:
 826  *         -EBADR:     This unit type does not support starting.
 827  *         -EALREADY:  Unit is already started.
 828  *         -EAGAIN:    An operation is already in progress. Retry later.
 829  *         -ECANCELED: Too many requests for now.
 830  */
 831 int unit_start(Unit *u) {
 832         UnitActiveState state;
 833         Unit *following;
 834
 835         assert(u);
 836
 837         if (u->meta.load_state != UNIT_LOADED)
 838                 return -EINVAL;
 839
 840         /* If this is already (being) started, then this will
 841          * succeed. Note that this will even succeed if this unit is
 842          * not startable by the user. This is relied on to detect when
 843          * we need to wait for units and when waiting is finished. */
 844         state = unit_active_state(u);
 845         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 846                 return -EALREADY;
 847
 848         /* If the conditions failed, don't do anything at all */
 849         if (!condition_test_list(u->meta.conditions)) {
 850                 log_debug("Starting of %s requested but condition failed. Ignoring.", u->meta.id);
 851                 return -EALREADY;
 852         }
 853
 854         /* Forward to the main object, if we aren't it. */
 855         if ((following = unit_following(u))) {
 856                 log_debug("Redirecting start request from %s to %s.", u->meta.id, following->meta.id);
 857                 return unit_start(following);
 858         }
 859
 860         /* If it is stopped, but we cannot start it, then fail */
 861         if (!UNIT_VTABLE(u)->start)
 862                 return -EBADR;
 863
 864         /* We don't suppress calls to ->start() here when we are
 865          * already starting, to allow this request to be used as a
 866          * "hurry up" call, for example when the unit is in some "auto
 867          * restart" state where it waits for a holdoff timer to elapse
 868          * before it will start again. */
 869
 870         unit_add_to_dbus_queue(u);
 871
 872         unit_status_printf(u, "Starting %s...\n", unit_description(u));
 873         return UNIT_VTABLE(u)->start(u);
 874 }
 875
 876 bool unit_can_start(Unit *u) {
 877         assert(u);
 878
 879         return !!UNIT_VTABLE(u)->start;
 880 }
 881
 882 bool unit_can_isolate(Unit *u) {
 883         assert(u);
 884
 885         return unit_can_start(u) &&
 886                 u->meta.allow_isolate;
 887 }
 888
 889 /* Errors:
 890  *         -EBADR:    This unit type does not support stopping.
 891  *         -EALREADY: Unit is already stopped.
 892  *         -EAGAIN:   An operation is already in progress. Retry later.
 893  */
 894 int unit_stop(Unit *u) {
 895         UnitActiveState state;
 896         Unit *following;
 897
 898         assert(u);
 899
 900         state = unit_active_state(u);
 901         if (UNIT_IS_INACTIVE_OR_FAILED(state))
 902                 return -EALREADY;
 903
 904         if ((following = unit_following(u))) {
 905                 log_debug("Redirecting stop request from %s to %s.", u->meta.id, following->meta.id);
 906                 return unit_stop(following);
 907         }
 908
 909         if (!UNIT_VTABLE(u)->stop)
 910                 return -EBADR;
 911
 912         unit_add_to_dbus_queue(u);
 913
 914         unit_status_printf(u, "Stopping %s...\n", unit_description(u));
 915         return UNIT_VTABLE(u)->stop(u);
 916 }
 917
 918 /* Errors:
 919  *         -EBADR:    This unit type does not support reloading.
 920  *         -ENOEXEC:  Unit is not started.
 921  *         -EAGAIN:   An operation is already in progress. Retry later.
 922  */
 923 int unit_reload(Unit *u) {
 924         UnitActiveState state;
 925         Unit *following;
 926
 927         assert(u);
 928
 929         if (u->meta.load_state != UNIT_LOADED)
 930                 return -EINVAL;
 931
 932         if (!unit_can_reload(u))
 933                 return -EBADR;
 934
 935         state = unit_active_state(u);
 936         if (state == UNIT_RELOADING)
 937                 return -EALREADY;
 938
 939         if (state != UNIT_ACTIVE)
 940                 return -ENOEXEC;
 941
 942         if ((following = unit_following(u))) {
 943                 log_debug("Redirecting reload request from %s to %s.", u->meta.id, following->meta.id);
 944                 return unit_reload(following);
 945         }
 946
 947         unit_add_to_dbus_queue(u);
 948         return UNIT_VTABLE(u)->reload(u);
 949 }
 950
 951 bool unit_can_reload(Unit *u) {
 952         assert(u);
 953
 954         if (!UNIT_VTABLE(u)->reload)
 955                 return false;
 956
 957         if (!UNIT_VTABLE(u)->can_reload)
 958                 return true;
 959
 960         return UNIT_VTABLE(u)->can_reload(u);
 961 }
 962
 963 static void unit_check_unneeded(Unit *u) {
 964         Iterator i;
 965         Unit *other;
 966
 967         assert(u);
 968
 969         /* If this service shall be shut down when unneeded then do
 970          * so. */
 971
 972         if (!u->meta.stop_when_unneeded)
 973                 return;
 974
 975         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 976                 return;
 977
 978         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 979                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 980                         return;
 981
 982         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 983                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 984                         return;
 985
 986         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 987                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 988                         return;
 989
 990         SET_FOREACH(other, u->meta.dependencies[UNIT_BOUND_BY], i)
 991                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 992                         return;
 993
 994         log_info("Service %s is not needed anymore. Stopping.", u->meta.id);
 995
 996         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 997         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL, NULL);
 998 }
 999
1000 static void retroactively_start_dependencies(Unit *u) {
1001         Iterator i;
1002         Unit *other;
1003
1004         assert(u);
1005         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
1006
1007         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
1008                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1009                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1010                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1011
1012         SET_FOREACH(other, u->meta.dependencies[UNIT_BIND_TO], i)
1013                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1014                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1015                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1016
1017         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1018                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1019                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1020                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
1021
1022         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
1023                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1024                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1025                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1026
1027         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
1028                 if (!set_get(u->meta.dependencies[UNIT_AFTER], other) &&
1029                     !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
1030                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL, NULL);
1031
1032         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
1033                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1034                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1035
1036         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTED_BY], i)
1037                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1038                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1039 }
1040
1041 static void retroactively_stop_dependencies(Unit *u) {
1042         Iterator i;
1043         Unit *other;
1044
1045         assert(u);
1046         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
1047
1048         /* Pull down units which are bound to us recursively if enabled */
1049         SET_FOREACH(other, u->meta.dependencies[UNIT_BOUND_BY], i)
1050                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1051                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL, NULL);
1052
1053         /* Garbage collect services that might not be needed anymore, if enabled */
1054         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
1055                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1056                         unit_check_unneeded(other);
1057         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1058                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1059                         unit_check_unneeded(other);
1060         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
1061                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1062                         unit_check_unneeded(other);
1063         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
1064                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1065                         unit_check_unneeded(other);
1066         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], 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_BIND_TO], i)
1070                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
1071                         unit_check_unneeded(other);
1072 }
1073
1074 void unit_trigger_on_failure(Unit *u) {
1075         Unit *other;
1076         Iterator i;
1077
1078         assert(u);
1079
1080         SET_FOREACH(other, u->meta.dependencies[UNIT_ON_FAILURE], i)
1081                 manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
1082 }
1083
1084 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_success) {
1085         dual_timestamp ts;
1086         bool unexpected;
1087
1088         assert(u);
1089         assert(os < _UNIT_ACTIVE_STATE_MAX);
1090         assert(ns < _UNIT_ACTIVE_STATE_MAX);
1091
1092         /* Note that this is called for all low-level state changes,
1093          * even if they might map to the same high-level
1094          * UnitActiveState! That means that ns == os is OK an expected
1095          * behaviour here. For example: if a mount point is remounted
1096          * this function will be called too! */
1097
1098         dual_timestamp_get(&ts);
1099
1100         if (UNIT_IS_INACTIVE_OR_FAILED(os) && !UNIT_IS_INACTIVE_OR_FAILED(ns))
1101                 u->meta.inactive_exit_timestamp = ts;
1102         else if (!UNIT_IS_INACTIVE_OR_FAILED(os) && UNIT_IS_INACTIVE_OR_FAILED(ns))
1103                 u->meta.inactive_enter_timestamp = ts;
1104
1105         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
1106                 u->meta.active_enter_timestamp = ts;
1107         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
1108                 u->meta.active_exit_timestamp = ts;
1109
1110         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1111                 cgroup_bonding_trim_list(u->meta.cgroup_bondings, true);
1112
1113         timer_unit_notify(u, ns);
1114         path_unit_notify(u, ns);
1115
1116         if (u->meta.job) {
1117                 unexpected = false;
1118
1119                 if (u->meta.job->state == JOB_WAITING)
1120
1121                         /* So we reached a different state for this
1122                          * job. Let's see if we can run it now if it
1123                          * failed previously due to EAGAIN. */
1124                         job_add_to_run_queue(u->meta.job);
1125
1126                 /* Let's check whether this state change constitutes a
1127                  * finished job, or maybe contradicts a running job and
1128                  * hence needs to invalidate jobs. */
1129
1130                 switch (u->meta.job->type) {
1131
1132                 case JOB_START:
1133                 case JOB_VERIFY_ACTIVE:
1134
1135                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
1136                                 job_finish_and_invalidate(u->meta.job, JOB_DONE);
1137                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
1138                                 unexpected = true;
1139
1140                                 if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1141                                         job_finish_and_invalidate(u->meta.job, ns == UNIT_FAILED ? JOB_FAILED : JOB_DONE);
1142                         }
1143
1144                         break;
1145
1146                 case JOB_RELOAD:
1147                 case JOB_RELOAD_OR_START:
1148
1149                         if (u->meta.job->state == JOB_RUNNING) {
1150                                 if (ns == UNIT_ACTIVE)
1151                                         job_finish_and_invalidate(u->meta.job, reload_success ? JOB_DONE : JOB_FAILED);
1152                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
1153                                         unexpected = true;
1154
1155                                         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1156                                                 job_finish_and_invalidate(u->meta.job, ns == UNIT_FAILED ? JOB_FAILED : JOB_DONE);
1157                                 }
1158                         }
1159
1160                         break;
1161
1162                 case JOB_STOP:
1163                 case JOB_RESTART:
1164                 case JOB_TRY_RESTART:
1165
1166                         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
1167                                 job_finish_and_invalidate(u->meta.job, JOB_DONE);
1168                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1169                                 unexpected = true;
1170                                 job_finish_and_invalidate(u->meta.job, JOB_FAILED);
1171                         }
1172
1173                         break;
1174
1175                 default:
1176                         assert_not_reached("Job type unknown");
1177                 }
1178
1179         } else
1180                 unexpected = true;
1181
1182         /* If this state change happened without being requested by a
1183          * job, then let's retroactively start or stop
1184          * dependencies. We skip that step when deserializing, since
1185          * we don't want to create any additional jobs just because
1186          * something is already activated. */
1187
1188         if (unexpected && u->meta.manager->n_deserializing <= 0) {
1189                 if (UNIT_IS_INACTIVE_OR_FAILED(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1190                         retroactively_start_dependencies(u);
1191                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1192                         retroactively_stop_dependencies(u);
1193         }
1194
1195         if (ns != os && ns == UNIT_FAILED) {
1196                 log_notice("Unit %s entered failed state.", u->meta.id);
1197                 unit_trigger_on_failure(u);
1198         }
1199
1200         /* Some names are special */
1201         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1202                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE))
1203                         /* The bus just might have become available,
1204                          * hence try to connect to it, if we aren't
1205                          * yet connected. */
1206                         bus_init(u->meta.manager, true);
1207
1208                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1209                         /* The syslog daemon just might have become
1210                          * available, hence try to connect to it, if
1211                          * we aren't yet connected. */
1212                         log_open();
1213
1214                 if (u->meta.type == UNIT_SERVICE &&
1215                     !UNIT_IS_ACTIVE_OR_RELOADING(os)) {
1216                         /* Write audit record if we have just finished starting up */
1217                         manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_START, true);
1218                         u->meta.in_audit = true;
1219                 }
1220
1221                 if (!UNIT_IS_ACTIVE_OR_RELOADING(os))
1222                         manager_send_unit_plymouth(u->meta.manager, u);
1223
1224         } else {
1225
1226                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1227                         /* The syslog daemon might just have
1228                          * terminated, hence try to disconnect from
1229                          * it. */
1230                         log_close_syslog();
1231
1232                 /* We don't care about D-Bus here, since we'll get an
1233                  * asynchronous notification for it anyway. */
1234
1235                 if (u->meta.type == UNIT_SERVICE &&
1236                     UNIT_IS_INACTIVE_OR_FAILED(ns) &&
1237                     !UNIT_IS_INACTIVE_OR_FAILED(os)) {
1238
1239                         /* Hmm, if there was no start record written
1240                          * write it now, so that we always have a nice
1241                          * pair */
1242                         if (!u->meta.in_audit) {
1243                                 manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_START, ns == UNIT_INACTIVE);
1244
1245                                 if (ns == UNIT_INACTIVE)
1246                                         manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_STOP, true);
1247                         } else
1248                                 /* Write audit record if we have just finished shutting down */
1249                                 manager_send_unit_audit(u->meta.manager, u, AUDIT_SERVICE_STOP, ns == UNIT_INACTIVE);
1250
1251                         u->meta.in_audit = false;
1252                 }
1253         }
1254
1255         /* Maybe we finished startup and are now ready for being
1256          * stopped because unneeded? */
1257         unit_check_unneeded(u);
1258
1259         unit_add_to_dbus_queue(u);
1260         unit_add_to_gc_queue(u);
1261 }
1262
1263 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1264         struct epoll_event ev;
1265
1266         assert(u);
1267         assert(fd >= 0);
1268         assert(w);
1269         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1270
1271         zero(ev);
1272         ev.data.ptr = w;
1273         ev.events = events;
1274
1275         if (epoll_ctl(u->meta.manager->epoll_fd,
1276                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1277                       fd,
1278                       &ev) < 0)
1279                 return -errno;
1280
1281         w->fd = fd;
1282         w->type = WATCH_FD;
1283         w->data.unit = u;
1284
1285         return 0;
1286 }
1287
1288 void unit_unwatch_fd(Unit *u, Watch *w) {
1289         assert(u);
1290         assert(w);
1291
1292         if (w->type == WATCH_INVALID)
1293                 return;
1294
1295         assert(w->type == WATCH_FD);
1296         assert(w->data.unit == u);
1297         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1298
1299         w->fd = -1;
1300         w->type = WATCH_INVALID;
1301         w->data.unit = NULL;
1302 }
1303
1304 int unit_watch_pid(Unit *u, pid_t pid) {
1305         assert(u);
1306         assert(pid >= 1);
1307
1308         /* Watch a specific PID. We only support one unit watching
1309          * each PID for now. */
1310
1311         return hashmap_put(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1312 }
1313
1314 void unit_unwatch_pid(Unit *u, pid_t pid) {
1315         assert(u);
1316         assert(pid >= 1);
1317
1318         hashmap_remove_value(u->meta.manager->watch_pids, LONG_TO_PTR(pid), u);
1319 }
1320
1321 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1322         struct itimerspec its;
1323         int flags, fd;
1324         bool ours;
1325
1326         assert(u);
1327         assert(w);
1328         assert(w->type == WATCH_INVALID || (w->type == WATCH_UNIT_TIMER && w->data.unit == u));
1329
1330         /* This will try to reuse the old timer if there is one */
1331
1332         if (w->type == WATCH_UNIT_TIMER) {
1333                 assert(w->data.unit == u);
1334                 assert(w->fd >= 0);
1335
1336                 ours = false;
1337                 fd = w->fd;
1338         } else if (w->type == WATCH_INVALID) {
1339
1340                 ours = true;
1341                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1342                         return -errno;
1343         } else
1344                 assert_not_reached("Invalid watch type");
1345
1346         zero(its);
1347
1348         if (delay <= 0) {
1349                 /* Set absolute time in the past, but not 0, since we
1350                  * don't want to disarm the timer */
1351                 its.it_value.tv_sec = 0;
1352                 its.it_value.tv_nsec = 1;
1353
1354                 flags = TFD_TIMER_ABSTIME;
1355         } else {
1356                 timespec_store(&its.it_value, delay);
1357                 flags = 0;
1358         }
1359
1360         /* This will also flush the elapse counter */
1361         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1362                 goto fail;
1363
1364         if (w->type == WATCH_INVALID) {
1365                 struct epoll_event ev;
1366
1367                 zero(ev);
1368                 ev.data.ptr = w;
1369                 ev.events = EPOLLIN;
1370
1371                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1372                         goto fail;
1373         }
1374
1375         w->type = WATCH_UNIT_TIMER;
1376         w->fd = fd;
1377         w->data.unit = u;
1378
1379         return 0;
1380
1381 fail:
1382         if (ours)
1383                 close_nointr_nofail(fd);
1384
1385         return -errno;
1386 }
1387
1388 void unit_unwatch_timer(Unit *u, Watch *w) {
1389         assert(u);
1390         assert(w);
1391
1392         if (w->type == WATCH_INVALID)
1393                 return;
1394
1395         assert(w->type == WATCH_UNIT_TIMER);
1396         assert(w->data.unit == u);
1397         assert(w->fd >= 0);
1398
1399         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1400         close_nointr_nofail(w->fd);
1401
1402         w->fd = -1;
1403         w->type = WATCH_INVALID;
1404         w->data.unit = NULL;
1405 }
1406
1407 bool unit_job_is_applicable(Unit *u, JobType j) {
1408         assert(u);
1409         assert(j >= 0 && j < _JOB_TYPE_MAX);
1410
1411         switch (j) {
1412
1413         case JOB_VERIFY_ACTIVE:
1414         case JOB_START:
1415         case JOB_STOP:
1416                 return true;
1417
1418         case JOB_RESTART:
1419         case JOB_TRY_RESTART:
1420                 return unit_can_start(u);
1421
1422         case JOB_RELOAD:
1423                 return unit_can_reload(u);
1424
1425         case JOB_RELOAD_OR_START:
1426                 return unit_can_reload(u) && unit_can_start(u);
1427
1428         default:
1429                 assert_not_reached("Invalid job type");
1430         }
1431 }
1432
1433 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1434
1435         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1436                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1437                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1438                 [UNIT_WANTS] = UNIT_WANTED_BY,
1439                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1440                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1441                 [UNIT_BIND_TO] = UNIT_BOUND_BY,
1442                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1443                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1444                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1445                 [UNIT_BOUND_BY] = UNIT_BIND_TO,
1446                 [UNIT_CONFLICTS] = UNIT_CONFLICTED_BY,
1447                 [UNIT_CONFLICTED_BY] = UNIT_CONFLICTS,
1448                 [UNIT_BEFORE] = UNIT_AFTER,
1449                 [UNIT_AFTER] = UNIT_BEFORE,
1450                 [UNIT_ON_FAILURE] = _UNIT_DEPENDENCY_INVALID,
1451                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1452                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1453         };
1454         int r, q = 0, v = 0, w = 0;
1455
1456         assert(u);
1457         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1458         assert(other);
1459
1460         u = unit_follow_merge(u);
1461         other = unit_follow_merge(other);
1462
1463         /* We won't allow dependencies on ourselves. We will not
1464          * consider them an error however. */
1465         if (u == other)
1466                 return 0;
1467
1468         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0)
1469                 return r;
1470
1471         if (inverse_table[d] != _UNIT_DEPENDENCY_INVALID)
1472                 if ((r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1473                         return r;
1474
1475         if (add_reference)
1476                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1477                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1478                         return r;
1479
1480         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1481                 return q;
1482
1483         if (inverse_table[d] != _UNIT_DEPENDENCY_INVALID)
1484                 if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1485                         r = v;
1486                         goto fail;
1487                 }
1488
1489         if (add_reference) {
1490                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1491                         r = w;
1492                         goto fail;
1493                 }
1494
1495                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1496                         goto fail;
1497         }
1498
1499         unit_add_to_dbus_queue(u);
1500         return 0;
1501
1502 fail:
1503         if (q > 0)
1504                 set_remove(u->meta.dependencies[d], other);
1505
1506         if (v > 0)
1507                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1508
1509         if (w > 0)
1510                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1511
1512         return r;
1513 }
1514
1515 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference) {
1516         int r;
1517
1518         assert(u);
1519
1520         if ((r = unit_add_dependency(u, d, other, add_reference)) < 0)
1521                 return r;
1522
1523         if ((r = unit_add_dependency(u, e, other, add_reference)) < 0)
1524                 return r;
1525
1526         return 0;
1527 }
1528
1529 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1530         char *s;
1531
1532         assert(u);
1533         assert(name || path);
1534
1535         if (!name)
1536                 name = file_name_from_path(path);
1537
1538         if (!unit_name_is_template(name)) {
1539                 *p = NULL;
1540                 return name;
1541         }
1542
1543         if (u->meta.instance)
1544                 s = unit_name_replace_instance(name, u->meta.instance);
1545         else {
1546                 char *i;
1547
1548                 if (!(i = unit_name_to_prefix(u->meta.id)))
1549                         return NULL;
1550
1551                 s = unit_name_replace_instance(name, i);
1552                 free(i);
1553         }
1554
1555         if (!s)
1556                 return NULL;
1557
1558         *p = s;
1559         return s;
1560 }
1561
1562 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1563         Unit *other;
1564         int r;
1565         char *s;
1566
1567         assert(u);
1568         assert(name || path);
1569
1570         if (!(name = resolve_template(u, name, path, &s)))
1571                 return -ENOMEM;
1572
1573         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1574                 goto finish;
1575
1576         r = unit_add_dependency(u, d, other, add_reference);
1577
1578 finish:
1579         free(s);
1580         return r;
1581 }
1582
1583 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1584         Unit *other;
1585         int r;
1586         char *s;
1587
1588         assert(u);
1589         assert(name || path);
1590
1591         if (!(name = resolve_template(u, name, path, &s)))
1592                 return -ENOMEM;
1593
1594         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1595                 goto finish;
1596
1597         r = unit_add_two_dependencies(u, d, e, other, add_reference);
1598
1599 finish:
1600         free(s);
1601         return r;
1602 }
1603
1604 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1605         Unit *other;
1606         int r;
1607         char *s;
1608
1609         assert(u);
1610         assert(name || path);
1611
1612         if (!(name = resolve_template(u, name, path, &s)))
1613                 return -ENOMEM;
1614
1615         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1616                 goto finish;
1617
1618         r = unit_add_dependency(other, d, u, add_reference);
1619
1620 finish:
1621         free(s);
1622         return r;
1623 }
1624
1625 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1626         Unit *other;
1627         int r;
1628         char *s;
1629
1630         assert(u);
1631         assert(name || path);
1632
1633         if (!(name = resolve_template(u, name, path, &s)))
1634                 return -ENOMEM;
1635
1636         if ((r = manager_load_unit(u->meta.manager, name, path, NULL, &other)) < 0)
1637                 goto finish;
1638
1639         if ((r = unit_add_two_dependencies(other, d, e, u, add_reference)) < 0)
1640                 goto finish;
1641
1642 finish:
1643         free(s);
1644         return r;
1645 }
1646
1647 int set_unit_path(const char *p) {
1648         char *cwd, *c;
1649         int r;
1650
1651         /* This is mostly for debug purposes */
1652
1653         if (path_is_absolute(p)) {
1654                 if (!(c = strdup(p)))
1655                         return -ENOMEM;
1656         } else {
1657                 if (!(cwd = get_current_dir_name()))
1658                         return -errno;
1659
1660                 r = asprintf(&c, "%s/%s", cwd, p);
1661                 free(cwd);
1662
1663                 if (r < 0)
1664                         return -ENOMEM;
1665         }
1666
1667         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1668                 r = -errno;
1669                 free(c);
1670                 return r;
1671         }
1672
1673         return 0;
1674 }
1675
1676 char *unit_dbus_path(Unit *u) {
1677         char *p, *e;
1678
1679         assert(u);
1680
1681         if (!u->meta.id)
1682                 return NULL;
1683
1684         if (!(e = bus_path_escape(u->meta.id)))
1685                 return NULL;
1686
1687         p = strappend("/org/freedesktop/systemd1/unit/", e);
1688         free(e);
1689
1690         return p;
1691 }
1692
1693 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1694         int r;
1695
1696         assert(u);
1697         assert(b);
1698
1699         assert(b->path);
1700
1701         if (!b->controller)
1702                 if (!(b->controller = strdup(SYSTEMD_CGROUP_CONTROLLER)))
1703                         return -ENOMEM;
1704
1705         /* Ensure this hasn't been added yet */
1706         assert(!b->unit);
1707
1708         if (streq(b->controller, SYSTEMD_CGROUP_CONTROLLER)) {
1709                 CGroupBonding *l;
1710
1711                 l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1712                 LIST_PREPEND(CGroupBonding, by_path, l, b);
1713
1714                 if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1715                         LIST_REMOVE(CGroupBonding, by_path, l, b);
1716                         return r;
1717                 }
1718         }
1719
1720         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1721         b->unit = u;
1722
1723         return 0;
1724 }
1725
1726 static char *default_cgroup_path(Unit *u) {
1727         char *p;
1728         int r;
1729
1730         assert(u);
1731
1732         if (u->meta.instance) {
1733                 char *t;
1734
1735                 if (!(t = unit_name_template(u->meta.id)))
1736                         return NULL;
1737
1738                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1739                 free(t);
1740         } else
1741                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1742
1743         return r < 0 ? NULL : p;
1744 }
1745
1746 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1747         char *controller = NULL, *path = NULL;
1748         CGroupBonding *b = NULL;
1749         int r;
1750
1751         assert(u);
1752         assert(name);
1753
1754         if ((r = cg_split_spec(name, &controller, &path)) < 0)
1755                 return r;
1756
1757         if (!path)
1758                 path = default_cgroup_path(u);
1759
1760         if (!controller)
1761                 controller = strdup(SYSTEMD_CGROUP_CONTROLLER);
1762
1763         if (!path || !controller) {
1764                 free(path);
1765                 free(controller);
1766
1767                 return -ENOMEM;
1768         }
1769
1770         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1771                 r = -EEXIST;
1772                 goto fail;
1773         }
1774
1775         if (!(b = new0(CGroupBonding, 1))) {
1776                 r = -ENOMEM;
1777                 goto fail;
1778         }
1779
1780         b->controller = controller;
1781         b->path = path;
1782         b->ours = false;
1783
1784         if ((r = unit_add_cgroup(u, b)) < 0)
1785                 goto fail;
1786
1787         return 0;
1788
1789 fail:
1790         free(path);
1791         free(controller);
1792         free(b);
1793
1794         return r;
1795 }
1796
1797 static int unit_add_one_default_cgroup(Unit *u, const char *controller) {
1798         CGroupBonding *b = NULL;
1799         int r = -ENOMEM;
1800
1801         assert(u);
1802
1803         if (!controller)
1804                 controller = SYSTEMD_CGROUP_CONTROLLER;
1805
1806         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller))
1807                 return 0;
1808
1809         if (!(b = new0(CGroupBonding, 1)))
1810                 return -ENOMEM;
1811
1812         if (!(b->controller = strdup(controller)))
1813                 goto fail;
1814
1815         if (!(b->path = default_cgroup_path(u)))
1816                 goto fail;
1817
1818         b->ours = true;
1819         b->essential = streq(controller, SYSTEMD_CGROUP_CONTROLLER);
1820
1821         if ((r = unit_add_cgroup(u, b)) < 0)
1822                 goto fail;
1823
1824         return 0;
1825
1826 fail:
1827         free(b->path);
1828         free(b->controller);
1829         free(b);
1830
1831         return r;
1832 }
1833
1834 int unit_add_default_cgroups(Unit *u) {
1835         char **c;
1836         int r;
1837         assert(u);
1838
1839         /* Adds in the default cgroups, if they weren't specified
1840          * otherwise. */
1841
1842         if ((r = unit_add_one_default_cgroup(u, NULL)) < 0)
1843                 return r;
1844
1845         STRV_FOREACH(c, u->meta.manager->default_controllers)
1846                 if ((r = unit_add_one_default_cgroup(u, *c)) < 0)
1847                         return r;
1848
1849         return 0;
1850 }
1851
1852 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1853         assert(u);
1854
1855         return cgroup_bonding_find_list(u->meta.cgroup_bondings, SYSTEMD_CGROUP_CONTROLLER);
1856 }
1857
1858 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1859         char *t;
1860         int r;
1861
1862         assert(u);
1863         assert(type);
1864         assert(_found);
1865
1866         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1867                 return -ENOMEM;
1868
1869         assert(!unit_has_name(u, t));
1870
1871         r = manager_load_unit(u->meta.manager, t, NULL, NULL, _found);
1872         free(t);
1873
1874         assert(r < 0 || *_found != u);
1875
1876         return r;
1877 }
1878
1879 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1880         Unit *found;
1881         char *t;
1882
1883         assert(u);
1884         assert(type);
1885         assert(_found);
1886
1887         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1888                 return -ENOMEM;
1889
1890         assert(!unit_has_name(u, t));
1891
1892         found = manager_get_unit(u->meta.manager, t);
1893         free(t);
1894
1895         if (!found)
1896                 return -ENOENT;
1897
1898         *_found = found;
1899         return 0;
1900 }
1901
1902 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1903         Unit *u = userdata;
1904         assert(u);
1905
1906         return unit_name_to_prefix_and_instance(u->meta.id);
1907 }
1908
1909 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1910         Unit *u = userdata;
1911         assert(u);
1912
1913         return unit_name_to_prefix(u->meta.id);
1914 }
1915
1916 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1917         Unit *u = userdata;
1918         char *p, *r;
1919
1920         assert(u);
1921
1922         if (!(p = unit_name_to_prefix(u->meta.id)))
1923                 return NULL;
1924
1925         r = unit_name_unescape(p);
1926         free(p);
1927
1928         return r;
1929 }
1930
1931 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1932         Unit *u = userdata;
1933         assert(u);
1934
1935         if (u->meta.instance)
1936                 return unit_name_unescape(u->meta.instance);
1937
1938         return strdup("");
1939 }
1940
1941 static char *specifier_filename(char specifier, void *data, void *userdata) {
1942         Unit *u = userdata;
1943         assert(u);
1944
1945         if (u->meta.instance)
1946                 return unit_name_path_unescape(u->meta.instance);
1947
1948         return unit_name_to_path(u->meta.instance);
1949 }
1950
1951 char *unit_name_printf(Unit *u, const char* format) {
1952
1953         /*
1954          * This will use the passed string as format string and
1955          * replace the following specifiers:
1956          *
1957          * %n: the full id of the unit                 (foo@bar.waldo)
1958          * %N: the id of the unit without the suffix   (foo@bar)
1959          * %p: the prefix                              (foo)
1960          * %i: the instance                            (bar)
1961          */
1962
1963         const Specifier table[] = {
1964                 { 'n', specifier_string,              u->meta.id },
1965                 { 'N', specifier_prefix_and_instance, NULL },
1966                 { 'p', specifier_prefix,              NULL },
1967                 { 'i', specifier_string,              u->meta.instance },
1968                 { 0, NULL, NULL }
1969         };
1970
1971         assert(u);
1972         assert(format);
1973
1974         return specifier_printf(format, table, u);
1975 }
1976
1977 char *unit_full_printf(Unit *u, const char *format) {
1978
1979         /* This is similar to unit_name_printf() but also supports
1980          * unescaping */
1981
1982         const Specifier table[] = {
1983                 { 'n', specifier_string,              u->meta.id },
1984                 { 'N', specifier_prefix_and_instance, NULL },
1985                 { 'p', specifier_prefix,              NULL },
1986                 { 'P', specifier_prefix_unescaped,    NULL },
1987                 { 'i', specifier_string,              u->meta.instance },
1988                 { 'I', specifier_instance_unescaped,  NULL },
1989                 { 'f', specifier_filename,            NULL },
1990                 { 0, NULL, NULL }
1991         };
1992
1993         assert(u);
1994         assert(format);
1995
1996         return specifier_printf(format, table, u);
1997 }
1998
1999 char **unit_full_printf_strv(Unit *u, char **l) {
2000         size_t n;
2001         char **r, **i, **j;
2002
2003         /* Applies unit_full_printf to every entry in l */
2004
2005         assert(u);
2006
2007         n = strv_length(l);
2008         if (!(r = new(char*, n+1)))
2009                 return NULL;
2010
2011         for (i = l, j = r; *i; i++, j++)
2012                 if (!(*j = unit_full_printf(u, *i)))
2013                         goto fail;
2014
2015         *j = NULL;
2016         return r;
2017
2018 fail:
2019         j--;
2020         while (j >= r)
2021                 free(*j);
2022
2023         free(r);
2024
2025         return NULL;
2026 }
2027
2028 int unit_watch_bus_name(Unit *u, const char *name) {
2029         assert(u);
2030         assert(name);
2031
2032         /* Watch a specific name on the bus. We only support one unit
2033          * watching each name for now. */
2034
2035         return hashmap_put(u->meta.manager->watch_bus, name, u);
2036 }
2037
2038 void unit_unwatch_bus_name(Unit *u, const char *name) {
2039         assert(u);
2040         assert(name);
2041
2042         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
2043 }
2044
2045 bool unit_can_serialize(Unit *u) {
2046         assert(u);
2047
2048         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
2049 }
2050
2051 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
2052         int r;
2053
2054         assert(u);
2055         assert(f);
2056         assert(fds);
2057
2058         if (!unit_can_serialize(u))
2059                 return 0;
2060
2061         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
2062                 return r;
2063
2064         if (u->meta.job)
2065                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
2066
2067         dual_timestamp_serialize(f, "inactive-exit-timestamp", &u->meta.inactive_exit_timestamp);
2068         dual_timestamp_serialize(f, "active-enter-timestamp", &u->meta.active_enter_timestamp);
2069         dual_timestamp_serialize(f, "active-exit-timestamp", &u->meta.active_exit_timestamp);
2070         dual_timestamp_serialize(f, "inactive-enter-timestamp", &u->meta.inactive_enter_timestamp);
2071
2072         /* End marker */
2073         fputc('\n', f);
2074         return 0;
2075 }
2076
2077 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
2078         va_list ap;
2079
2080         assert(u);
2081         assert(f);
2082         assert(key);
2083         assert(format);
2084
2085         fputs(key, f);
2086         fputc('=', f);
2087
2088         va_start(ap, format);
2089         vfprintf(f, format, ap);
2090         va_end(ap);
2091
2092         fputc('\n', f);
2093 }
2094
2095 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
2096         assert(u);
2097         assert(f);
2098         assert(key);
2099         assert(value);
2100
2101         fprintf(f, "%s=%s\n", key, value);
2102 }
2103
2104 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
2105         int r;
2106
2107         assert(u);
2108         assert(f);
2109         assert(fds);
2110
2111         if (!unit_can_serialize(u))
2112                 return 0;
2113
2114         for (;;) {
2115                 char line[1024], *l, *v;
2116                 size_t k;
2117
2118                 if (!fgets(line, sizeof(line), f)) {
2119                         if (feof(f))
2120                                 return 0;
2121                         return -errno;
2122                 }
2123
2124                 char_array_0(line);
2125                 l = strstrip(line);
2126
2127                 /* End marker */
2128                 if (l[0] == 0)
2129                         return 0;
2130
2131                 k = strcspn(l, "=");
2132
2133                 if (l[k] == '=') {
2134                         l[k] = 0;
2135                         v = l+k+1;
2136                 } else
2137                         v = l+k;
2138
2139                 if (streq(l, "job")) {
2140                         JobType type;
2141
2142                         if ((type = job_type_from_string(v)) < 0)
2143                                 log_debug("Failed to parse job type value %s", v);
2144                         else
2145                                 u->meta.deserialized_job = type;
2146
2147                         continue;
2148                 } else if (streq(l, "inactive-exit-timestamp")) {
2149                         dual_timestamp_deserialize(v, &u->meta.inactive_exit_timestamp);
2150                         continue;
2151                 } else if (streq(l, "active-enter-timestamp")) {
2152                         dual_timestamp_deserialize(v, &u->meta.active_enter_timestamp);
2153                         continue;
2154                 } else if (streq(l, "active-exit-timestamp")) {
2155                         dual_timestamp_deserialize(v, &u->meta.active_exit_timestamp);
2156                         continue;
2157                 } else if (streq(l, "inactive-enter-timestamp")) {
2158                         dual_timestamp_deserialize(v, &u->meta.inactive_enter_timestamp);
2159                         continue;
2160                 }
2161
2162                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
2163                         return r;
2164         }
2165 }
2166
2167 int unit_add_node_link(Unit *u, const char *what, bool wants) {
2168         Unit *device;
2169         char *e;
2170         int r;
2171
2172         assert(u);
2173
2174         if (!what)
2175                 return 0;
2176
2177         /* Adds in links to the device node that this unit is based on */
2178
2179         if (!is_device_path(what))
2180                 return 0;
2181
2182         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
2183                 return -ENOMEM;
2184
2185         r = manager_load_unit(u->meta.manager, e, NULL, NULL, &device);
2186         free(e);
2187
2188         if (r < 0)
2189                 return r;
2190
2191         if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_BIND_TO, device, true)) < 0)
2192                 return r;
2193
2194         if (wants)
2195                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
2196                         return r;
2197
2198         return 0;
2199 }
2200
2201 int unit_coldplug(Unit *u) {
2202         int r;
2203
2204         assert(u);
2205
2206         if (UNIT_VTABLE(u)->coldplug)
2207                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
2208                         return r;
2209
2210         if (u->meta.deserialized_job >= 0) {
2211                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL, NULL)) < 0)
2212                         return r;
2213
2214                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
2215         }
2216
2217         return 0;
2218 }
2219
2220 void unit_status_printf(Unit *u, const char *format, ...) {
2221         va_list ap;
2222
2223         assert(u);
2224         assert(format);
2225
2226         if (!UNIT_VTABLE(u)->show_status)
2227                 return;
2228
2229         if (u->meta.manager->running_as != MANAGER_SYSTEM)
2230                 return;
2231
2232         if (!u->meta.manager->show_status)
2233                 return;
2234
2235         if (!manager_is_booting_or_shutting_down(u->meta.manager))
2236                 return;
2237
2238         va_start(ap, format);
2239         status_vprintf(format, ap);
2240         va_end(ap);
2241 }
2242
2243 bool unit_need_daemon_reload(Unit *u) {
2244         struct stat st;
2245
2246         assert(u);
2247
2248         if (!u->meta.fragment_path)
2249                 return false;
2250
2251         zero(st);
2252         if (stat(u->meta.fragment_path, &st) < 0)
2253                 /* What, cannot access this anymore? */
2254                 return true;
2255
2256         return
2257                 u->meta.fragment_mtime &&
2258                 timespec_load(&st.st_mtim) != u->meta.fragment_mtime;
2259 }
2260
2261 void unit_reset_failed(Unit *u) {
2262         assert(u);
2263
2264         if (UNIT_VTABLE(u)->reset_failed)
2265                 UNIT_VTABLE(u)->reset_failed(u);
2266 }
2267
2268 Unit *unit_following(Unit *u) {
2269         assert(u);
2270
2271         if (UNIT_VTABLE(u)->following)
2272                 return UNIT_VTABLE(u)->following(u);
2273
2274         return NULL;
2275 }
2276
2277 bool unit_pending_inactive(Unit *u) {
2278         assert(u);
2279
2280         /* Returns true if the unit is inactive or going down */
2281
2282         if (UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)))
2283                 return true;
2284
2285         if (u->meta.job && u->meta.job->type == JOB_STOP)
2286                 return true;
2287
2288         return false;
2289 }
2290
2291 bool unit_pending_active(Unit *u) {
2292         assert(u);
2293
2294         /* Returns true if the unit is inactive or going down */
2295
2296         if (UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
2297                 return true;
2298
2299         if (u->meta.job &&
2300             (u->meta.job->type == JOB_START ||
2301              u->meta.job->type == JOB_RELOAD_OR_START ||
2302              u->meta.job->type == JOB_RESTART))
2303                 return true;
2304
2305         return false;
2306 }
2307
2308 UnitType unit_name_to_type(const char *n) {
2309         UnitType t;
2310
2311         assert(n);
2312
2313         for (t = 0; t < _UNIT_TYPE_MAX; t++)
2314                 if (endswith(n, unit_vtable[t]->suffix))
2315                         return t;
2316
2317         return _UNIT_TYPE_INVALID;
2318 }
2319
2320 bool unit_name_is_valid(const char *n, bool template_ok) {
2321         UnitType t;
2322
2323         t = unit_name_to_type(n);
2324         if (t < 0 || t >= _UNIT_TYPE_MAX)
2325                 return false;
2326
2327         return unit_name_is_valid_no_type(n, template_ok);
2328 }
2329
2330 int unit_kill(Unit *u, KillWho w, KillMode m, int signo, DBusError *error) {
2331         assert(u);
2332         assert(w >= 0 && w < _KILL_WHO_MAX);
2333         assert(m >= 0 && m < _KILL_MODE_MAX);
2334         assert(signo > 0);
2335         assert(signo < _NSIG);
2336
2337         if (m == KILL_NONE)
2338                 return 0;
2339
2340         if (!UNIT_VTABLE(u)->kill)
2341                 return -ENOTSUP;
2342
2343         return UNIT_VTABLE(u)->kill(u, w, m, signo, error);
2344 }
2345
2346
2347 int unit_following_set(Unit *u, Set **s) {
2348         assert(u);
2349         assert(s);
2350
2351         if (UNIT_VTABLE(u)->following_set)
2352                 return UNIT_VTABLE(u)->following_set(u, s);
2353
2354         *s = NULL;
2355         return 0;
2356 }
2357
2358 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
2359         [UNIT_STUB] = "stub",
2360         [UNIT_LOADED] = "loaded",
2361         [UNIT_ERROR] = "error",
2362         [UNIT_MERGED] = "merged",
2363         [UNIT_MASKED] = "masked"
2364 };
2365
2366 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
2367
2368 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
2369         [UNIT_ACTIVE] = "active",
2370         [UNIT_RELOADING] = "reloading",
2371         [UNIT_INACTIVE] = "inactive",
2372         [UNIT_FAILED] = "failed",
2373         [UNIT_ACTIVATING] = "activating",
2374         [UNIT_DEACTIVATING] = "deactivating"
2375 };
2376
2377 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
2378
2379 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
2380         [UNIT_REQUIRES] = "Requires",
2381         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
2382         [UNIT_WANTS] = "Wants",
2383         [UNIT_REQUISITE] = "Requisite",
2384         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
2385         [UNIT_REQUIRED_BY] = "RequiredBy",
2386         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
2387         [UNIT_BIND_TO] = "BindTo",
2388         [UNIT_WANTED_BY] = "WantedBy",
2389         [UNIT_CONFLICTS] = "Conflicts",
2390         [UNIT_CONFLICTED_BY] = "ConflictedBy",
2391         [UNIT_BOUND_BY] = "BoundBy",
2392         [UNIT_BEFORE] = "Before",
2393         [UNIT_AFTER] = "After",
2394         [UNIT_REFERENCES] = "References",
2395         [UNIT_REFERENCED_BY] = "ReferencedBy",
2396         [UNIT_ON_FAILURE] = "OnFailure"
2397 };
2398
2399 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);