src/unit.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <sys/epoll.h>
  26 #include <sys/timerfd.h>
  27 #include <sys/poll.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30
  31 #include "set.h"
  32 #include "unit.h"
  33 #include "macro.h"
  34 #include "strv.h"
  35 #include "load-fragment.h"
  36 #include "load-dropin.h"
  37 #include "log.h"
  38 #include "unit-name.h"
  39 #include "specifier.h"
  40 #include "dbus-unit.h"
  41
  42 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  43         [UNIT_SERVICE] = &service_vtable,
  44         [UNIT_TIMER] = &timer_vtable,
  45         [UNIT_SOCKET] = &socket_vtable,
  46         [UNIT_TARGET] = &target_vtable,
  47         [UNIT_DEVICE] = &device_vtable,
  48         [UNIT_MOUNT] = &mount_vtable,
  49         [UNIT_AUTOMOUNT] = &automount_vtable,
  50         [UNIT_SNAPSHOT] = &snapshot_vtable,
  51         [UNIT_SWAP] = &swap_vtable,
  52         [UNIT_PATH] = &path_vtable
  53 };
  54
  55 Unit *unit_new(Manager *m) {
  56         Unit *u;
  57
  58         assert(m);
  59
  60         if (!(u = new0(Unit, 1)))
  61                 return NULL;
  62
  63         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  64                 free(u);
  65                 return NULL;
  66         }
  67
  68         u->meta.manager = m;
  69         u->meta.type = _UNIT_TYPE_INVALID;
  70         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  71
  72         return u;
  73 }
  74
  75 bool unit_has_name(Unit *u, const char *name) {
  76         assert(u);
  77         assert(name);
  78
  79         return !!set_get(u->meta.names, (char*) name);
  80 }
  81
  82 int unit_add_name(Unit *u, const char *text) {
  83         UnitType t;
  84         char *s = NULL, *i = NULL;
  85         int r;
  86
  87         assert(u);
  88         assert(text);
  89
  90         if (unit_name_is_template(text)) {
  91                 if (!u->meta.instance)
  92                         return -EINVAL;
  93
  94                 s = unit_name_replace_instance(text, u->meta.instance);
  95         } else
  96                 s = strdup(text);
  97
  98         if (!s)
  99                 return -ENOMEM;
 100
 101         if (!unit_name_is_valid(s)) {
 102                 r = -EINVAL;
 103                 goto fail;
 104         }
 105
 106         assert_se((t = unit_name_to_type(s)) >= 0);
 107
 108         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 109                 r = -EINVAL;
 110                 goto fail;
 111         }
 112
 113         if ((r = unit_name_to_instance(s, &i)) < 0)
 114                 goto fail;
 115
 116         if (i && unit_vtable[t]->no_instances)
 117                 goto fail;
 118
 119         if (u->meta.type != _UNIT_TYPE_INVALID && !streq_ptr(u->meta.instance, i)) {
 120                 r = -EINVAL;
 121                 goto fail;
 122         }
 123
 124         if (unit_vtable[t]->no_alias &&
 125             !set_isempty(u->meta.names) &&
 126             !set_get(u->meta.names, s)) {
 127                 r = -EEXIST;
 128                 goto fail;
 129         }
 130
 131         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 132                 r = -E2BIG;
 133                 goto fail;
 134         }
 135
 136         if ((r = set_put(u->meta.names, s)) < 0) {
 137                 if (r == -EEXIST)
 138                         r = 0;
 139                 goto fail;
 140         }
 141
 142         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 143                 set_remove(u->meta.names, s);
 144                 goto fail;
 145         }
 146
 147         if (u->meta.type == _UNIT_TYPE_INVALID) {
 148
 149                 u->meta.type = t;
 150                 u->meta.id = s;
 151                 u->meta.instance = i;
 152
 153                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 154
 155                 if (UNIT_VTABLE(u)->init)
 156                         UNIT_VTABLE(u)->init(u);
 157         } else
 158                 free(i);
 159
 160         unit_add_to_dbus_queue(u);
 161         return 0;
 162
 163 fail:
 164         free(s);
 165         free(i);
 166
 167         return r;
 168 }
 169
 170 int unit_choose_id(Unit *u, const char *name) {
 171         char *s, *t = NULL;
 172
 173         assert(u);
 174         assert(name);
 175
 176         if (unit_name_is_template(name)) {
 177
 178                 if (!u->meta.instance)
 179                         return -EINVAL;
 180
 181                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 182                         return -ENOMEM;
 183
 184                 name = t;
 185         }
 186
 187         /* Selects one of the names of this unit as the id */
 188         s = set_get(u->meta.names, (char*) name);
 189         free(t);
 190
 191         if (!s)
 192                 return -ENOENT;
 193
 194         u->meta.id = s;
 195         unit_add_to_dbus_queue(u);
 196
 197         return 0;
 198 }
 199
 200 int unit_set_description(Unit *u, const char *description) {
 201         char *s;
 202
 203         assert(u);
 204
 205         if (!(s = strdup(description)))
 206                 return -ENOMEM;
 207
 208         free(u->meta.description);
 209         u->meta.description = s;
 210
 211         unit_add_to_dbus_queue(u);
 212         return 0;
 213 }
 214
 215 bool unit_check_gc(Unit *u) {
 216         assert(u);
 217
 218         if (u->meta.load_state == UNIT_STUB)
 219                 return true;
 220
 221         if (UNIT_VTABLE(u)->no_gc)
 222                 return true;
 223
 224         if (u->meta.job)
 225                 return true;
 226
 227         if (unit_active_state(u) != UNIT_INACTIVE)
 228                 return true;
 229
 230         if (UNIT_VTABLE(u)->check_gc)
 231                 if (UNIT_VTABLE(u)->check_gc(u))
 232                         return true;
 233
 234         return false;
 235 }
 236
 237 void unit_add_to_load_queue(Unit *u) {
 238         assert(u);
 239         assert(u->meta.type != _UNIT_TYPE_INVALID);
 240
 241         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 242                 return;
 243
 244         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 245         u->meta.in_load_queue = true;
 246 }
 247
 248 void unit_add_to_cleanup_queue(Unit *u) {
 249         assert(u);
 250
 251         if (u->meta.in_cleanup_queue)
 252                 return;
 253
 254         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 255         u->meta.in_cleanup_queue = true;
 256 }
 257
 258 void unit_add_to_gc_queue(Unit *u) {
 259         assert(u);
 260
 261         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 262                 return;
 263
 264         if (unit_check_gc(u))
 265                 return;
 266
 267         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 268         u->meta.in_gc_queue = true;
 269
 270         u->meta.manager->n_in_gc_queue ++;
 271
 272         if (u->meta.manager->gc_queue_timestamp <= 0)
 273                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 274 }
 275
 276 void unit_add_to_dbus_queue(Unit *u) {
 277         assert(u);
 278         assert(u->meta.type != _UNIT_TYPE_INVALID);
 279
 280         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 281                 return;
 282
 283         if (set_isempty(u->meta.manager->subscribed)) {
 284                 u->meta.sent_dbus_new_signal = true;
 285                 return;
 286         }
 287
 288         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 289         u->meta.in_dbus_queue = true;
 290 }
 291
 292 static void bidi_set_free(Unit *u, Set *s) {
 293         Iterator i;
 294         Unit *other;
 295
 296         assert(u);
 297
 298         /* Frees the set and makes sure we are dropped from the
 299          * inverse pointers */
 300
 301         SET_FOREACH(other, s, i) {
 302                 UnitDependency d;
 303
 304                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 305                         set_remove(other->meta.dependencies[d], u);
 306
 307                 unit_add_to_gc_queue(other);
 308         }
 309
 310         set_free(s);
 311 }
 312
 313 void unit_free(Unit *u) {
 314         UnitDependency d;
 315         Iterator i;
 316         char *t;
 317
 318         assert(u);
 319
 320         bus_unit_send_removed_signal(u);
 321
 322         if (u->meta.load_state != UNIT_STUB)
 323                 if (UNIT_VTABLE(u)->done)
 324                         UNIT_VTABLE(u)->done(u);
 325
 326         SET_FOREACH(t, u->meta.names, i)
 327                 hashmap_remove_value(u->meta.manager->units, t, u);
 328
 329         if (u->meta.job)
 330                 job_free(u->meta.job);
 331
 332         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 333                 bidi_set_free(u, u->meta.dependencies[d]);
 334
 335         if (u->meta.type != _UNIT_TYPE_INVALID)
 336                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 337
 338         if (u->meta.in_load_queue)
 339                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 340
 341         if (u->meta.in_dbus_queue)
 342                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 343
 344         if (u->meta.in_cleanup_queue)
 345                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 346
 347         if (u->meta.in_gc_queue) {
 348                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 349                 u->meta.manager->n_in_gc_queue--;
 350         }
 351
 352         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 353
 354         free(u->meta.description);
 355         free(u->meta.fragment_path);
 356
 357         set_free_free(u->meta.names);
 358
 359         free(u->meta.instance);
 360
 361         free(u);
 362 }
 363
 364 UnitActiveState unit_active_state(Unit *u) {
 365         assert(u);
 366
 367         if (u->meta.load_state != UNIT_LOADED)
 368                 return UNIT_INACTIVE;
 369
 370         return UNIT_VTABLE(u)->active_state(u);
 371 }
 372
 373 const char* unit_sub_state_to_string(Unit *u) {
 374         assert(u);
 375
 376         return UNIT_VTABLE(u)->sub_state_to_string(u);
 377 }
 378
 379 static void complete_move(Set **s, Set **other) {
 380         assert(s);
 381         assert(other);
 382
 383         if (!*other)
 384                 return;
 385
 386         if (*s)
 387                 set_move(*s, *other);
 388         else {
 389                 *s = *other;
 390                 *other = NULL;
 391         }
 392 }
 393
 394 static void merge_names(Unit *u, Unit *other) {
 395         char *t;
 396         Iterator i;
 397
 398         assert(u);
 399         assert(other);
 400
 401         complete_move(&u->meta.names, &other->meta.names);
 402
 403         set_free_free(other->meta.names);
 404         other->meta.names = NULL;
 405         other->meta.id = NULL;
 406
 407         SET_FOREACH(t, u->meta.names, i)
 408                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 409 }
 410
 411 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 412         Iterator i;
 413         Unit *back;
 414         int r;
 415
 416         assert(u);
 417         assert(other);
 418         assert(d < _UNIT_DEPENDENCY_MAX);
 419
 420         SET_FOREACH(back, other->meta.dependencies[d], i) {
 421                 UnitDependency k;
 422
 423                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 424                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 425
 426                                 if (r == -EEXIST)
 427                                         set_remove(back->meta.dependencies[k], other);
 428                                 else
 429                                         assert(r == -ENOENT);
 430                         }
 431         }
 432
 433         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 434
 435         set_free(other->meta.dependencies[d]);
 436         other->meta.dependencies[d] = NULL;
 437 }
 438
 439 int unit_merge(Unit *u, Unit *other) {
 440         UnitDependency d;
 441
 442         assert(u);
 443         assert(other);
 444         assert(u->meta.manager == other->meta.manager);
 445         assert(u->meta.type != _UNIT_TYPE_INVALID);
 446
 447         other = unit_follow_merge(other);
 448
 449         if (other == u)
 450                 return 0;
 451
 452         if (u->meta.type != other->meta.type)
 453                 return -EINVAL;
 454
 455         if (!streq_ptr(u->meta.instance, other->meta.instance))
 456                 return -EINVAL;
 457
 458         if (other->meta.load_state != UNIT_STUB &&
 459             other->meta.load_state != UNIT_FAILED)
 460                 return -EEXIST;
 461
 462         if (other->meta.job)
 463                 return -EEXIST;
 464
 465         if (unit_active_state(other) != UNIT_INACTIVE)
 466                 return -EEXIST;
 467
 468         /* Merge names */
 469         merge_names(u, other);
 470
 471         /* Merge dependencies */
 472         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 473                 merge_dependencies(u, other, d);
 474
 475         other->meta.load_state = UNIT_MERGED;
 476         other->meta.merged_into = u;
 477
 478         /* If there is still some data attached to the other node, we
 479          * don't need it anymore, and can free it. */
 480         if (other->meta.load_state != UNIT_STUB)
 481                 if (UNIT_VTABLE(other)->done)
 482                         UNIT_VTABLE(other)->done(other);
 483
 484         unit_add_to_dbus_queue(u);
 485         unit_add_to_cleanup_queue(other);
 486
 487         return 0;
 488 }
 489
 490 int unit_merge_by_name(Unit *u, const char *name) {
 491         Unit *other;
 492         int r;
 493         char *s = NULL;
 494
 495         assert(u);
 496         assert(name);
 497
 498         if (unit_name_is_template(name)) {
 499                 if (!u->meta.instance)
 500                         return -EINVAL;
 501
 502                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 503                         return -ENOMEM;
 504
 505                 name = s;
 506         }
 507
 508         if (!(other = manager_get_unit(u->meta.manager, name)))
 509                 r = unit_add_name(u, name);
 510         else
 511                 r = unit_merge(u, other);
 512
 513         free(s);
 514         return r;
 515 }
 516
 517 Unit* unit_follow_merge(Unit *u) {
 518         assert(u);
 519
 520         while (u->meta.load_state == UNIT_MERGED)
 521                 assert_se(u = u->meta.merged_into);
 522
 523         return u;
 524 }
 525
 526 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 527         int r;
 528
 529         assert(u);
 530         assert(c);
 531
 532         if (c->std_output != EXEC_OUTPUT_KMSG &&
 533             c->std_output != EXEC_OUTPUT_SYSLOG &&
 534             c->std_error != EXEC_OUTPUT_KMSG &&
 535             c->std_error != EXEC_OUTPUT_SYSLOG)
 536                 return 0;
 537
 538         /* If syslog or kernel logging is requested, make sure our own
 539          * logging daemon is run first. */
 540
 541         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 542                 return r;
 543
 544         if (u->meta.manager->running_as != MANAGER_SESSION)
 545                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 546                         return r;
 547
 548         return 0;
 549 }
 550
 551 const char *unit_description(Unit *u) {
 552         assert(u);
 553
 554         if (u->meta.description)
 555                 return u->meta.description;
 556
 557         return u->meta.id;
 558 }
 559
 560 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 561         char *t;
 562         UnitDependency d;
 563         Iterator i;
 564         char *p2;
 565         const char *prefix2;
 566         CGroupBonding *b;
 567         char
 568                 timestamp1[FORMAT_TIMESTAMP_MAX],
 569                 timestamp2[FORMAT_TIMESTAMP_MAX],
 570                 timestamp3[FORMAT_TIMESTAMP_MAX],
 571                 timestamp4[FORMAT_TIMESTAMP_MAX];
 572
 573         assert(u);
 574         assert(u->meta.type >= 0);
 575
 576         if (!prefix)
 577                 prefix = "";
 578         p2 = strappend(prefix, "\t");
 579         prefix2 = p2 ? p2 : prefix;
 580
 581         fprintf(f,
 582                 "%s-> Unit %s:\n"
 583                 "%s\tDescription: %s\n"
 584                 "%s\tInstance: %s\n"
 585                 "%s\tUnit Load State: %s\n"
 586                 "%s\tUnit Active State: %s\n"
 587                 "%s\tInactive Exit Timestamp: %s\n"
 588                 "%s\tActive Enter Timestamp: %s\n"
 589                 "%s\tActive Exit Timestamp: %s\n"
 590                 "%s\tInactive Enter Timestamp: %s\n"
 591                 "%s\tGC Check Good: %s\n"
 592                 "%s\tOnly By Dependency: %s\n",
 593                 prefix, u->meta.id,
 594                 prefix, unit_description(u),
 595                 prefix, strna(u->meta.instance),
 596                 prefix, unit_load_state_to_string(u->meta.load_state),
 597                 prefix, unit_active_state_to_string(unit_active_state(u)),
 598                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 599                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 600                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 601                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 602                 prefix, yes_no(unit_check_gc(u)),
 603                 prefix, yes_no(u->meta.only_by_dependency));
 604
 605         SET_FOREACH(t, u->meta.names, i)
 606                 fprintf(f, "%s\tName: %s\n", prefix, t);
 607
 608         if (u->meta.fragment_path)
 609                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 610
 611         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 612                 Unit *other;
 613
 614                 SET_FOREACH(other, u->meta.dependencies[d], i)
 615                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 616         }
 617
 618         if (u->meta.load_state == UNIT_LOADED) {
 619                 fprintf(f,
 620                         "%s\tRecursive Stop: %s\n"
 621                         "%s\tStop When Unneeded: %s\n",
 622                         prefix, yes_no(u->meta.recursive_stop),
 623                         prefix, yes_no(u->meta.stop_when_unneeded));
 624
 625                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 626                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 627                                 prefix, b->controller, b->path);
 628
 629                 if (UNIT_VTABLE(u)->dump)
 630                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 631
 632         } else if (u->meta.load_state == UNIT_MERGED)
 633                 fprintf(f,
 634                         "%s\tMerged into: %s\n",
 635                         prefix, u->meta.merged_into->meta.id);
 636
 637         if (u->meta.job)
 638                 job_dump(u->meta.job, f, prefix2);
 639
 640         free(p2);
 641 }
 642
 643 /* Common implementation for multiple backends */
 644 int unit_load_fragment_and_dropin(Unit *u) {
 645         int r;
 646
 647         assert(u);
 648
 649         /* Load a .service file */
 650         if ((r = unit_load_fragment(u)) < 0)
 651                 return r;
 652
 653         if (u->meta.load_state == UNIT_STUB)
 654                 return -ENOENT;
 655
 656         /* Load drop-in directory data */
 657         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 658                 return r;
 659
 660         return 0;
 661 }
 662
 663 /* Common implementation for multiple backends */
 664 int unit_load_fragment_and_dropin_optional(Unit *u) {
 665         int r;
 666
 667         assert(u);
 668
 669         /* Same as unit_load_fragment_and_dropin(), but whether
 670          * something can be loaded or not doesn't matter. */
 671
 672         /* Load a .service file */
 673         if ((r = unit_load_fragment(u)) < 0)
 674                 return r;
 675
 676         if (u->meta.load_state == UNIT_STUB)
 677                 u->meta.load_state = UNIT_LOADED;
 678
 679         /* Load drop-in directory data */
 680         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 681                 return r;
 682
 683         return 0;
 684 }
 685
 686 /* Common implementation for multiple backends */
 687 int unit_load_nop(Unit *u) {
 688         assert(u);
 689
 690         if (u->meta.load_state == UNIT_STUB)
 691                 u->meta.load_state = UNIT_LOADED;
 692
 693         return 0;
 694 }
 695
 696 int unit_load(Unit *u) {
 697         int r;
 698
 699         assert(u);
 700
 701         if (u->meta.in_load_queue) {
 702                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 703                 u->meta.in_load_queue = false;
 704         }
 705
 706         if (u->meta.type == _UNIT_TYPE_INVALID)
 707                 return -EINVAL;
 708
 709         if (u->meta.load_state != UNIT_STUB)
 710                 return 0;
 711
 712         if (UNIT_VTABLE(u)->load)
 713                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 714                         goto fail;
 715
 716         if (u->meta.load_state == UNIT_STUB) {
 717                 r = -ENOENT;
 718                 goto fail;
 719         }
 720
 721         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 722
 723         unit_add_to_dbus_queue(unit_follow_merge(u));
 724         unit_add_to_gc_queue(u);
 725
 726         return 0;
 727
 728 fail:
 729         u->meta.load_state = UNIT_FAILED;
 730         unit_add_to_dbus_queue(u);
 731
 732         log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 733
 734         return r;
 735 }
 736
 737 /* Errors:
 738  *         -EBADR:     This unit type does not support starting.
 739  *         -EALREADY:  Unit is already started.
 740  *         -EAGAIN:    An operation is already in progress. Retry later.
 741  *         -ECANCELED: Too many requests for now.
 742  */
 743 int unit_start(Unit *u) {
 744         UnitActiveState state;
 745
 746         assert(u);
 747
 748         /* If this is already (being) started, then this will
 749          * succeed. Note that this will even succeed if this unit is
 750          * not startable by the user. This is relied on to detect when
 751          * we need to wait for units and when waiting is finished. */
 752         state = unit_active_state(u);
 753         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 754                 return -EALREADY;
 755
 756         /* If it is stopped, but we cannot start it, then fail */
 757         if (!UNIT_VTABLE(u)->start)
 758                 return -EBADR;
 759
 760         /* We don't suppress calls to ->start() here when we are
 761          * already starting, to allow this request to be used as a
 762          * "hurry up" call, for example when the unit is in some "auto
 763          * restart" state where it waits for a holdoff timer to elapse
 764          * before it will start again. */
 765
 766         unit_add_to_dbus_queue(u);
 767         return UNIT_VTABLE(u)->start(u);
 768 }
 769
 770 bool unit_can_start(Unit *u) {
 771         assert(u);
 772
 773         return !!UNIT_VTABLE(u)->start;
 774 }
 775
 776 /* Errors:
 777  *         -EBADR:    This unit type does not support stopping.
 778  *         -EALREADY: Unit is already stopped.
 779  *         -EAGAIN:   An operation is already in progress. Retry later.
 780  */
 781 int unit_stop(Unit *u) {
 782         UnitActiveState state;
 783
 784         assert(u);
 785
 786         state = unit_active_state(u);
 787         if (state == UNIT_INACTIVE)
 788                 return -EALREADY;
 789
 790         if (!UNIT_VTABLE(u)->stop)
 791                 return -EBADR;
 792
 793         unit_add_to_dbus_queue(u);
 794         return UNIT_VTABLE(u)->stop(u);
 795 }
 796
 797 /* Errors:
 798  *         -EBADR:    This unit type does not support reloading.
 799  *         -ENOEXEC:  Unit is not started.
 800  *         -EAGAIN:   An operation is already in progress. Retry later.
 801  */
 802 int unit_reload(Unit *u) {
 803         UnitActiveState state;
 804
 805         assert(u);
 806
 807         if (!unit_can_reload(u))
 808                 return -EBADR;
 809
 810         state = unit_active_state(u);
 811         if (unit_active_state(u) == UNIT_ACTIVE_RELOADING)
 812                 return -EALREADY;
 813
 814         if (unit_active_state(u) != UNIT_ACTIVE)
 815                 return -ENOEXEC;
 816
 817         unit_add_to_dbus_queue(u);
 818         return UNIT_VTABLE(u)->reload(u);
 819 }
 820
 821 bool unit_can_reload(Unit *u) {
 822         assert(u);
 823
 824         if (!UNIT_VTABLE(u)->reload)
 825                 return false;
 826
 827         if (!UNIT_VTABLE(u)->can_reload)
 828                 return true;
 829
 830         return UNIT_VTABLE(u)->can_reload(u);
 831 }
 832
 833 static void unit_check_uneeded(Unit *u) {
 834         Iterator i;
 835         Unit *other;
 836
 837         assert(u);
 838
 839         /* If this service shall be shut down when unneeded then do
 840          * so. */
 841
 842         if (!u->meta.stop_when_unneeded)
 843                 return;
 844
 845         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 846                 return;
 847
 848         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 849                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 850                         return;
 851
 852         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 853                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 854                         return;
 855
 856         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 857                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 858                         return;
 859
 860         log_debug("Service %s is not needed anymore. Stopping.", u->meta.id);
 861
 862         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 863         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL);
 864 }
 865
 866 static void retroactively_start_dependencies(Unit *u) {
 867         Iterator i;
 868         Unit *other;
 869
 870         assert(u);
 871         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
 872
 873         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 874                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 875                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 876
 877         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 878                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 879                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 880
 881         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 882                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 883                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 884
 885         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 886                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 887                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 888
 889         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
 890                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 891                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 892 }
 893
 894 static void retroactively_stop_dependencies(Unit *u) {
 895         Iterator i;
 896         Unit *other;
 897
 898         assert(u);
 899         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
 900
 901         if (u->meta.recursive_stop) {
 902                 /* Pull down units need us recursively if enabled */
 903                 SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 904                         if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 905                                 manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 906         }
 907
 908         /* Garbage collect services that might not be needed anymore, if enabled */
 909         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 910                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 911                         unit_check_uneeded(other);
 912         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 913                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 914                         unit_check_uneeded(other);
 915         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 916                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 917                         unit_check_uneeded(other);
 918         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 919                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 920                         unit_check_uneeded(other);
 921         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
 922                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 923                         unit_check_uneeded(other);
 924 }
 925
 926 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
 927         bool unexpected = false;
 928         timestamp ts;
 929
 930         assert(u);
 931         assert(os < _UNIT_ACTIVE_STATE_MAX);
 932         assert(ns < _UNIT_ACTIVE_STATE_MAX);
 933
 934         /* Note that this is called for all low-level state changes,
 935          * even if they might map to the same high-level
 936          * UnitActiveState! That means that ns == os is OK an expected
 937          * behaviour here. For example: if a mount point is remounted
 938          * this function will be called too and the utmp code below
 939          * relies on that! */
 940
 941         timestamp_get(&ts);
 942
 943         if (os == UNIT_INACTIVE && ns != UNIT_INACTIVE)
 944                 u->meta.inactive_exit_timestamp = ts;
 945         else if (os != UNIT_INACTIVE && ns == UNIT_INACTIVE)
 946                 u->meta.inactive_enter_timestamp = ts;
 947
 948         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
 949                 u->meta.active_enter_timestamp = ts;
 950         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
 951                 u->meta.active_exit_timestamp = ts;
 952
 953         timer_unit_notify(u, ns);
 954         path_unit_notify(u, ns);
 955
 956         if (u->meta.job) {
 957
 958                 if (u->meta.job->state == JOB_WAITING)
 959
 960                         /* So we reached a different state for this
 961                          * job. Let's see if we can run it now if it
 962                          * failed previously due to EAGAIN. */
 963                         job_add_to_run_queue(u->meta.job);
 964
 965
 966                 /* Let's check whether this state change constitutes a
 967                  * finished job, or maybe cotradicts a running job and
 968                  * hence needs to invalidate jobs. */
 969
 970                 switch (u->meta.job->type) {
 971
 972                 case JOB_START:
 973                 case JOB_VERIFY_ACTIVE:
 974
 975                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
 976                                 job_finish_and_invalidate(u->meta.job, true);
 977                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
 978                                 unexpected = true;
 979                                 job_finish_and_invalidate(u->meta.job, false);
 980                         }
 981
 982                         break;
 983
 984                 case JOB_RELOAD:
 985                 case JOB_RELOAD_OR_START:
 986
 987                         if (u->meta.job->state == JOB_RUNNING) {
 988                                 if (ns == UNIT_ACTIVE)
 989                                         job_finish_and_invalidate(u->meta.job, true);
 990                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_ACTIVE_RELOADING) {
 991                                         unexpected = true;
 992                                         job_finish_and_invalidate(u->meta.job, false);
 993                                 }
 994                         }
 995
 996                         break;
 997
 998                 case JOB_STOP:
 999                 case JOB_RESTART:
1000                 case JOB_TRY_RESTART:
1001
1002                         if (ns == UNIT_INACTIVE)
1003                                 job_finish_and_invalidate(u->meta.job, true);
1004                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1005                                 unexpected = true;
1006                                 job_finish_and_invalidate(u->meta.job, false);
1007                         }
1008
1009                         break;
1010
1011                 default:
1012                         assert_not_reached("Job type unknown");
1013                 }
1014         }
1015
1016         /* If this state change happened without being requested by a
1017          * job, then let's retroactively start or stop dependencies */
1018
1019         if (unexpected) {
1020                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1021                         retroactively_start_dependencies(u);
1022                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1023                         retroactively_stop_dependencies(u);
1024         }
1025
1026         /* Some names are special */
1027         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1028                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1029                         /* The bus just might have become available,
1030                          * hence try to connect to it, if we aren't
1031                          * yet connected. */
1032                         bus_init_system(u->meta.manager);
1033                         bus_init_api(u->meta.manager);
1034                 }
1035
1036                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1037                         /* The syslog daemon just might have become
1038                          * available, hence try to connect to it, if
1039                          * we aren't yet connected. */
1040                         log_open();
1041
1042                 if (u->meta.type == UNIT_MOUNT)
1043                         /* Another directory became available, let's
1044                          * check if that is enough to write our utmp
1045                          * entry. */
1046                         manager_write_utmp_reboot(u->meta.manager);
1047
1048                 if (u->meta.type == UNIT_TARGET)
1049                         /* A target got activated, maybe this is a runlevel? */
1050                         manager_write_utmp_runlevel(u->meta.manager, u);
1051
1052         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1053
1054                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1055                         /* The syslog daemon might just have
1056                          * terminated, hence try to disconnect from
1057                          * it. */
1058                         log_close_syslog();
1059
1060                 /* We don't care about D-Bus here, since we'll get an
1061                  * asynchronous notification for it anyway. */
1062         }
1063
1064         /* Maybe we finished startup and are now ready for being
1065          * stopped because unneeded? */
1066         unit_check_uneeded(u);
1067
1068         unit_add_to_dbus_queue(u);
1069         unit_add_to_gc_queue(u);
1070 }
1071
1072 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1073         struct epoll_event ev;
1074
1075         assert(u);
1076         assert(fd >= 0);
1077         assert(w);
1078         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1079
1080         zero(ev);
1081         ev.data.ptr = w;
1082         ev.events = events;
1083
1084         if (epoll_ctl(u->meta.manager->epoll_fd,
1085                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1086                       fd,
1087                       &ev) < 0)
1088                 return -errno;
1089
1090         w->fd = fd;
1091         w->type = WATCH_FD;
1092         w->data.unit = u;
1093
1094         return 0;
1095 }
1096
1097 void unit_unwatch_fd(Unit *u, Watch *w) {
1098         assert(u);
1099         assert(w);
1100
1101         if (w->type == WATCH_INVALID)
1102                 return;
1103
1104         assert(w->type == WATCH_FD);
1105         assert(w->data.unit == u);
1106         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1107
1108         w->fd = -1;
1109         w->type = WATCH_INVALID;
1110         w->data.unit = NULL;
1111 }
1112
1113 int unit_watch_pid(Unit *u, pid_t pid) {
1114         assert(u);
1115         assert(pid >= 1);
1116
1117         /* Watch a specific PID. We only support one unit watching
1118          * each PID for now. */
1119
1120         return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1121 }
1122
1123 void unit_unwatch_pid(Unit *u, pid_t pid) {
1124         assert(u);
1125         assert(pid >= 1);
1126
1127         hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1128 }
1129
1130 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1131         struct itimerspec its;
1132         int flags, fd;
1133         bool ours;
1134
1135         assert(u);
1136         assert(w);
1137         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1138
1139         /* This will try to reuse the old timer if there is one */
1140
1141         if (w->type == WATCH_TIMER) {
1142                 ours = false;
1143                 fd = w->fd;
1144         } else {
1145                 ours = true;
1146                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1147                         return -errno;
1148         }
1149
1150         zero(its);
1151
1152         if (delay <= 0) {
1153                 /* Set absolute time in the past, but not 0, since we
1154                  * don't want to disarm the timer */
1155                 its.it_value.tv_sec = 0;
1156                 its.it_value.tv_nsec = 1;
1157
1158                 flags = TFD_TIMER_ABSTIME;
1159         } else {
1160                 timespec_store(&its.it_value, delay);
1161                 flags = 0;
1162         }
1163
1164         /* This will also flush the elapse counter */
1165         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1166                 goto fail;
1167
1168         if (w->type == WATCH_INVALID) {
1169                 struct epoll_event ev;
1170
1171                 zero(ev);
1172                 ev.data.ptr = w;
1173                 ev.events = EPOLLIN;
1174
1175                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1176                         goto fail;
1177         }
1178
1179         w->fd = fd;
1180         w->type = WATCH_TIMER;
1181         w->data.unit = u;
1182
1183         return 0;
1184
1185 fail:
1186         if (ours)
1187                 close_nointr_nofail(fd);
1188
1189         return -errno;
1190 }
1191
1192 void unit_unwatch_timer(Unit *u, Watch *w) {
1193         assert(u);
1194         assert(w);
1195
1196         if (w->type == WATCH_INVALID)
1197                 return;
1198
1199         assert(w->type == WATCH_TIMER && w->data.unit == u);
1200
1201         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1202         close_nointr_nofail(w->fd);
1203
1204         w->fd = -1;
1205         w->type = WATCH_INVALID;
1206         w->data.unit = NULL;
1207 }
1208
1209 bool unit_job_is_applicable(Unit *u, JobType j) {
1210         assert(u);
1211         assert(j >= 0 && j < _JOB_TYPE_MAX);
1212
1213         switch (j) {
1214
1215         case JOB_VERIFY_ACTIVE:
1216         case JOB_START:
1217                 return true;
1218
1219         case JOB_STOP:
1220         case JOB_RESTART:
1221         case JOB_TRY_RESTART:
1222                 return unit_can_start(u);
1223
1224         case JOB_RELOAD:
1225                 return unit_can_reload(u);
1226
1227         case JOB_RELOAD_OR_START:
1228                 return unit_can_reload(u) && unit_can_start(u);
1229
1230         default:
1231                 assert_not_reached("Invalid job type");
1232         }
1233 }
1234
1235 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1236
1237         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1238                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1239                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1240                 [UNIT_WANTS] = UNIT_WANTED_BY,
1241                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1242                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1243                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1244                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1245                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1246                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1247                 [UNIT_BEFORE] = UNIT_AFTER,
1248                 [UNIT_AFTER] = UNIT_BEFORE,
1249                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1250                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1251         };
1252         int r, q = 0, v = 0, w = 0;
1253
1254         assert(u);
1255         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1256         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1257         assert(other);
1258
1259         /* We won't allow dependencies on ourselves. We will not
1260          * consider them an error however. */
1261         if (u == other)
1262                 return 0;
1263
1264         if (UNIT_VTABLE(u)->no_requires &&
1265             (d == UNIT_REQUIRES ||
1266              d == UNIT_REQUIRES_OVERRIDABLE ||
1267              d == UNIT_REQUISITE ||
1268              d == UNIT_REQUISITE_OVERRIDABLE)) {
1269                     return -EINVAL;
1270         }
1271
1272         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1273             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1274                 return r;
1275
1276         if (add_reference)
1277                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1278                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1279                         return r;
1280
1281         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1282                 return q;
1283
1284         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1285                 r = v;
1286                 goto fail;
1287         }
1288
1289         if (add_reference) {
1290                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1291                         r = w;
1292                         goto fail;
1293                 }
1294
1295                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1296                         goto fail;
1297         }
1298
1299         unit_add_to_dbus_queue(u);
1300         return 0;
1301
1302 fail:
1303         if (q > 0)
1304                 set_remove(u->meta.dependencies[d], other);
1305
1306         if (v > 0)
1307                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1308
1309         if (w > 0)
1310                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1311
1312         return r;
1313 }
1314
1315 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1316         char *s;
1317
1318         assert(u);
1319         assert(name || path);
1320
1321         if (!name)
1322                 name = file_name_from_path(path);
1323
1324         if (!unit_name_is_template(name)) {
1325                 *p = NULL;
1326                 return name;
1327         }
1328
1329         if (u->meta.instance)
1330                 s = unit_name_replace_instance(name, u->meta.instance);
1331         else {
1332                 char *i;
1333
1334                 if (!(i = unit_name_to_prefix(u->meta.id)))
1335                         return NULL;
1336
1337                 s = unit_name_replace_instance(name, i);
1338                 free(i);
1339         }
1340
1341         if (!s)
1342                 return NULL;
1343
1344         *p = s;
1345         return s;
1346 }
1347
1348 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1349         Unit *other;
1350         int r;
1351         char *s;
1352
1353         assert(u);
1354         assert(name || path);
1355
1356         if (!(name = resolve_template(u, name, path, &s)))
1357                 return -ENOMEM;
1358
1359         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1360                 goto finish;
1361
1362         r = unit_add_dependency(u, d, other, add_reference);
1363
1364 finish:
1365         free(s);
1366         return r;
1367 }
1368
1369 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1370         Unit *other;
1371         int r;
1372         char *s;
1373
1374         assert(u);
1375         assert(name || path);
1376
1377         if (!(name = resolve_template(u, name, path, &s)))
1378                 return -ENOMEM;
1379
1380         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1381                 goto finish;
1382
1383         r = unit_add_dependency(other, d, u, add_reference);
1384
1385 finish:
1386         free(s);
1387         return r;
1388 }
1389
1390 int set_unit_path(const char *p) {
1391         char *cwd, *c;
1392         int r;
1393
1394         /* This is mostly for debug purposes */
1395
1396         if (path_is_absolute(p)) {
1397                 if (!(c = strdup(p)))
1398                         return -ENOMEM;
1399         } else {
1400                 if (!(cwd = get_current_dir_name()))
1401                         return -errno;
1402
1403                 r = asprintf(&c, "%s/%s", cwd, p);
1404                 free(cwd);
1405
1406                 if (r < 0)
1407                         return -ENOMEM;
1408         }
1409
1410         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1411                 r = -errno;
1412                 free(c);
1413                 return r;
1414         }
1415
1416         return 0;
1417 }
1418
1419 char *unit_dbus_path(Unit *u) {
1420         char *p, *e;
1421
1422         assert(u);
1423
1424         if (!(e = bus_path_escape(u->meta.id)))
1425                 return NULL;
1426
1427         if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
1428                 free(e);
1429                 return NULL;
1430         }
1431
1432         free(e);
1433         return p;
1434 }
1435
1436 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1437         CGroupBonding *l;
1438         int r;
1439
1440         assert(u);
1441         assert(b);
1442         assert(b->path);
1443
1444         /* Ensure this hasn't been added yet */
1445         assert(!b->unit);
1446
1447         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1448         LIST_PREPEND(CGroupBonding, by_path, l, b);
1449
1450         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1451                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1452                 return r;
1453         }
1454
1455         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1456         b->unit = u;
1457
1458         return 0;
1459 }
1460
1461 static char *default_cgroup_path(Unit *u) {
1462         char *p;
1463         int r;
1464
1465         assert(u);
1466
1467         if (u->meta.instance) {
1468                 char *t;
1469
1470                 if (!(t = unit_name_template(u->meta.id)))
1471                         return NULL;
1472
1473                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1474                 free(t);
1475         } else
1476                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1477
1478         return r < 0 ? NULL : p;
1479 }
1480
1481 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1482         size_t n;
1483         char *controller = NULL, *path = NULL;
1484         CGroupBonding *b = NULL;
1485         int r;
1486
1487         assert(u);
1488         assert(name);
1489
1490         /* Detect controller name */
1491         n = strcspn(name, ":");
1492
1493         if (name[n] == 0 ||
1494             (name[n] == ':' && name[n+1] == 0)) {
1495
1496                 /* Only controller name, no path? */
1497
1498                 if (!(path = default_cgroup_path(u)))
1499                         return -ENOMEM;
1500
1501         } else {
1502                 const char *p;
1503
1504                 /* Controller name, and path. */
1505                 p = name+n+1;
1506
1507                 if (!path_is_absolute(p))
1508                         return -EINVAL;
1509
1510                 if (!(path = strdup(p)))
1511                         return -ENOMEM;
1512         }
1513
1514         if (n > 0)
1515                 controller = strndup(name, n);
1516         else
1517                 controller = strdup(u->meta.manager->cgroup_controller);
1518
1519         if (!controller) {
1520                 r = -ENOMEM;
1521                 goto fail;
1522         }
1523
1524         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1525                 r = -EEXIST;
1526                 goto fail;
1527         }
1528
1529         if (!(b = new0(CGroupBonding, 1))) {
1530                 r = -ENOMEM;
1531                 goto fail;
1532         }
1533
1534         b->controller = controller;
1535         b->path = path;
1536         b->only_us = false;
1537         b->clean_up = false;
1538
1539         if ((r = unit_add_cgroup(u, b)) < 0)
1540                 goto fail;
1541
1542         return 0;
1543
1544 fail:
1545         free(path);
1546         free(controller);
1547         free(b);
1548
1549         return r;
1550 }
1551
1552 int unit_add_default_cgroup(Unit *u) {
1553         CGroupBonding *b;
1554         int r = -ENOMEM;
1555
1556         assert(u);
1557
1558         /* Adds in the default cgroup data, if it wasn't specified yet */
1559
1560         if (unit_get_default_cgroup(u))
1561                 return 0;
1562
1563         if (!(b = new0(CGroupBonding, 1)))
1564                 return -ENOMEM;
1565
1566         if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
1567                 goto fail;
1568
1569         if (!(b->path = default_cgroup_path(u)))
1570                 goto fail;
1571
1572         b->clean_up = true;
1573         b->only_us = true;
1574
1575         if ((r = unit_add_cgroup(u, b)) < 0)
1576                 goto fail;
1577
1578         return 0;
1579
1580 fail:
1581         free(b->path);
1582         free(b->controller);
1583         free(b);
1584
1585         return r;
1586 }
1587
1588 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1589         assert(u);
1590
1591         return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
1592 }
1593
1594 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1595         char *t;
1596         int r;
1597
1598         assert(u);
1599         assert(type);
1600         assert(_found);
1601
1602         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1603                 return -ENOMEM;
1604
1605         assert(!unit_has_name(u, t));
1606
1607         r = manager_load_unit(u->meta.manager, t, NULL, _found);
1608         free(t);
1609
1610         assert(r < 0 || *_found != u);
1611
1612         return r;
1613 }
1614
1615 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1616         Unit *found;
1617         char *t;
1618
1619         assert(u);
1620         assert(type);
1621         assert(_found);
1622
1623         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1624                 return -ENOMEM;
1625
1626         assert(!unit_has_name(u, t));
1627
1628         found = manager_get_unit(u->meta.manager, t);
1629         free(t);
1630
1631         if (!found)
1632                 return -ENOENT;
1633
1634         *_found = found;
1635         return 0;
1636 }
1637
1638 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1639         Unit *u = userdata;
1640         assert(u);
1641
1642         return unit_name_to_prefix_and_instance(u->meta.id);
1643 }
1644
1645 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1646         Unit *u = userdata;
1647         assert(u);
1648
1649         return unit_name_to_prefix(u->meta.id);
1650 }
1651
1652 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1653         Unit *u = userdata;
1654         char *p, *r;
1655
1656         assert(u);
1657
1658         if (!(p = unit_name_to_prefix(u->meta.id)))
1659                 return NULL;
1660
1661         r = unit_name_unescape(p);
1662         free(p);
1663
1664         return r;
1665 }
1666
1667 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1668         Unit *u = userdata;
1669         assert(u);
1670
1671         if (u->meta.instance)
1672                 return unit_name_unescape(u->meta.instance);
1673
1674         return strdup("");
1675 }
1676
1677 char *unit_name_printf(Unit *u, const char* format) {
1678
1679         /*
1680          * This will use the passed string as format string and
1681          * replace the following specifiers:
1682          *
1683          * %n: the full id of the unit                 (foo@bar.waldo)
1684          * %N: the id of the unit without the suffix   (foo@bar)
1685          * %p: the prefix                              (foo)
1686          * %i: the instance                            (bar)
1687          */
1688
1689         const Specifier table[] = {
1690                 { 'n', specifier_string,              u->meta.id },
1691                 { 'N', specifier_prefix_and_instance, NULL },
1692                 { 'p', specifier_prefix,              NULL },
1693                 { 'i', specifier_string,              u->meta.instance },
1694                 { 0, NULL, NULL }
1695         };
1696
1697         assert(u);
1698         assert(format);
1699
1700         return specifier_printf(format, table, u);
1701 }
1702
1703 char *unit_full_printf(Unit *u, const char *format) {
1704
1705         /* This is similar to unit_name_printf() but also supports
1706          * unescaping */
1707
1708         const Specifier table[] = {
1709                 { 'n', specifier_string,              u->meta.id },
1710                 { 'N', specifier_prefix_and_instance, NULL },
1711                 { 'p', specifier_prefix,              NULL },
1712                 { 'P', specifier_prefix_unescaped,    NULL },
1713                 { 'i', specifier_string,              u->meta.instance },
1714                 { 'I', specifier_instance_unescaped,  NULL },
1715                 { 0, NULL, NULL }
1716         };
1717
1718         assert(u);
1719         assert(format);
1720
1721         return specifier_printf(format, table, u);
1722 }
1723
1724 char **unit_full_printf_strv(Unit *u, char **l) {
1725         size_t n;
1726         char **r, **i, **j;
1727
1728         /* Applies unit_full_printf to every entry in l */
1729
1730         assert(u);
1731
1732         n = strv_length(l);
1733         if (!(r = new(char*, n+1)))
1734                 return NULL;
1735
1736         for (i = l, j = r; *i; i++, j++)
1737                 if (!(*j = unit_full_printf(u, *i)))
1738                         goto fail;
1739
1740         *j = NULL;
1741         return r;
1742
1743 fail:
1744         j--;
1745         while (j >= r)
1746                 free(*j);
1747
1748         free(r);
1749
1750         return NULL;
1751 }
1752
1753 int unit_watch_bus_name(Unit *u, const char *name) {
1754         assert(u);
1755         assert(name);
1756
1757         /* Watch a specific name on the bus. We only support one unit
1758          * watching each name for now. */
1759
1760         return hashmap_put(u->meta.manager->watch_bus, name, u);
1761 }
1762
1763 void unit_unwatch_bus_name(Unit *u, const char *name) {
1764         assert(u);
1765         assert(name);
1766
1767         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1768 }
1769
1770 bool unit_can_serialize(Unit *u) {
1771         assert(u);
1772
1773         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1774 }
1775
1776 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1777         int r;
1778
1779         assert(u);
1780         assert(f);
1781         assert(fds);
1782
1783         if (!unit_can_serialize(u))
1784                 return 0;
1785
1786         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1787                 return r;
1788
1789         if (u->meta.job)
1790                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1791
1792         /* End marker */
1793         fputc('\n', f);
1794         return 0;
1795 }
1796
1797 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1798         va_list ap;
1799
1800         assert(u);
1801         assert(f);
1802         assert(key);
1803         assert(format);
1804
1805         fputs(key, f);
1806         fputc('=', f);
1807
1808         va_start(ap, format);
1809         vfprintf(f, format, ap);
1810         va_end(ap);
1811
1812         fputc('\n', f);
1813 }
1814
1815 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1816         assert(u);
1817         assert(f);
1818         assert(key);
1819         assert(value);
1820
1821         fprintf(f, "%s=%s\n", key, value);
1822 }
1823
1824 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1825         int r;
1826
1827         assert(u);
1828         assert(f);
1829         assert(fds);
1830
1831         if (!unit_can_serialize(u))
1832                 return 0;
1833
1834         for (;;) {
1835                 char line[1024], *l, *v;
1836                 size_t k;
1837
1838                 if (!fgets(line, sizeof(line), f)) {
1839                         if (feof(f))
1840                                 return 0;
1841                         return -errno;
1842                 }
1843
1844                 l = strstrip(line);
1845
1846                 /* End marker */
1847                 if (l[0] == 0)
1848                         return 0;
1849
1850                 k = strcspn(l, "=");
1851
1852                 if (l[k] == '=') {
1853                         l[k] = 0;
1854                         v = l+k+1;
1855                 } else
1856                         v = l+k;
1857
1858                 if (streq(l, "job")) {
1859                         JobType type;
1860
1861                         if ((type = job_type_from_string(v)) < 0)
1862                                 log_debug("Failed to parse job type value %s", v);
1863                         else
1864                                 u->meta.deserialized_job = type;
1865
1866                         continue;
1867                 }
1868
1869                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1870                         return r;
1871         }
1872 }
1873
1874 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1875         Unit *device;
1876         char *e;
1877         int r;
1878
1879         assert(u);
1880
1881         if (!what)
1882                 return 0;
1883
1884         /* Adds in links to the device node that this unit is based on */
1885
1886         if (!is_device_path(what))
1887                 return 0;
1888
1889         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1890                 return -ENOMEM;
1891
1892         r = manager_load_unit(u->meta.manager, e, NULL, &device);
1893         free(e);
1894
1895         if (r < 0)
1896                 return r;
1897
1898         if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
1899                 return r;
1900
1901         if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
1902                 return r;
1903
1904         if (wants)
1905                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1906                         return r;
1907
1908         return 0;
1909 }
1910
1911 int unit_coldplug(Unit *u) {
1912         int r;
1913
1914         assert(u);
1915
1916         if (UNIT_VTABLE(u)->coldplug)
1917                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
1918                         return r;
1919
1920         if (u->meta.deserialized_job >= 0) {
1921                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL)) < 0)
1922                         return r;
1923
1924                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
1925         }
1926
1927         return 0;
1928 }
1929
1930 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
1931         [UNIT_SERVICE] = "service",
1932         [UNIT_TIMER] = "timer",
1933         [UNIT_SOCKET] = "socket",
1934         [UNIT_TARGET] = "target",
1935         [UNIT_DEVICE] = "device",
1936         [UNIT_MOUNT] = "mount",
1937         [UNIT_AUTOMOUNT] = "automount",
1938         [UNIT_SNAPSHOT] = "snapshot",
1939         [UNIT_SWAP] = "swap"
1940 };
1941
1942 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
1943
1944 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
1945         [UNIT_STUB] = "stub",
1946         [UNIT_LOADED] = "loaded",
1947         [UNIT_FAILED] = "failed",
1948         [UNIT_MERGED] = "merged"
1949 };
1950
1951 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
1952
1953 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
1954         [UNIT_ACTIVE] = "active",
1955         [UNIT_INACTIVE] = "inactive",
1956         [UNIT_ACTIVATING] = "activating",
1957         [UNIT_DEACTIVATING] = "deactivating"
1958 };
1959
1960 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
1961
1962 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
1963         [UNIT_REQUIRES] = "Requires",
1964         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
1965         [UNIT_WANTS] = "Wants",
1966         [UNIT_REQUISITE] = "Requisite",
1967         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
1968         [UNIT_REQUIRED_BY] = "RequiredBy",
1969         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
1970         [UNIT_WANTED_BY] = "WantedBy",
1971         [UNIT_CONFLICTS] = "Conflicts",
1972         [UNIT_BEFORE] = "Before",
1973         [UNIT_AFTER] = "After",
1974         [UNIT_REFERENCES] = "References",
1975         [UNIT_REFERENCED_BY] = "ReferencedBy"
1976 };
1977
1978 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
1979
1980 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
1981         [KILL_CONTROL_GROUP] = "control-group",
1982         [KILL_PROCESS_GROUP] = "process-group",
1983         [KILL_PROCESS] = "process",
1984         [KILL_NONE] = "none"
1985 };
1986
1987 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);