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 };
  53
  54 Unit *unit_new(Manager *m) {
  55         Unit *u;
  56
  57         assert(m);
  58
  59         if (!(u = new0(Unit, 1)))
  60                 return NULL;
  61
  62         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  63                 free(u);
  64                 return NULL;
  65         }
  66
  67         u->meta.manager = m;
  68         u->meta.type = _UNIT_TYPE_INVALID;
  69
  70         return u;
  71 }
  72
  73 bool unit_has_name(Unit *u, const char *name) {
  74         assert(u);
  75         assert(name);
  76
  77         return !!set_get(u->meta.names, (char*) name);
  78 }
  79
  80 int unit_add_name(Unit *u, const char *text) {
  81         UnitType t;
  82         char *s = NULL, *i = NULL;
  83         int r;
  84
  85         assert(u);
  86         assert(text);
  87
  88         if (unit_name_is_template(text)) {
  89                 if (!u->meta.instance)
  90                         return -EINVAL;
  91
  92                 s = unit_name_replace_instance(text, u->meta.instance);
  93         } else
  94                 s = strdup(text);
  95
  96         if (!s)
  97                 return -ENOMEM;
  98
  99         if (!unit_name_is_valid(s)) {
 100                 r = -EINVAL;
 101                 goto fail;
 102         }
 103
 104         assert_se((t = unit_name_to_type(s)) >= 0);
 105
 106         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 107                 r = -EINVAL;
 108                 goto fail;
 109         }
 110
 111         if ((r = unit_name_to_instance(s, &i)) < 0)
 112                 goto fail;
 113
 114         if (i && unit_vtable[t]->no_instances)
 115                 goto fail;
 116
 117         if (u->meta.type != _UNIT_TYPE_INVALID && !streq_ptr(u->meta.instance, i)) {
 118                 r = -EINVAL;
 119                 goto fail;
 120         }
 121
 122         if (unit_vtable[t]->no_alias &&
 123             !set_isempty(u->meta.names) &&
 124             !set_get(u->meta.names, s)) {
 125                 r = -EEXIST;
 126                 goto fail;
 127         }
 128
 129         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 130                 r = -E2BIG;
 131                 goto fail;
 132         }
 133
 134         if ((r = set_put(u->meta.names, s)) < 0) {
 135                 if (r == -EEXIST)
 136                         r = 0;
 137                 goto fail;
 138         }
 139
 140         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 141                 set_remove(u->meta.names, s);
 142                 goto fail;
 143         }
 144
 145         if (u->meta.type == _UNIT_TYPE_INVALID) {
 146
 147                 u->meta.type = t;
 148                 u->meta.id = s;
 149                 u->meta.instance = i;
 150
 151                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 152
 153                 if (UNIT_VTABLE(u)->init)
 154                         UNIT_VTABLE(u)->init(u);
 155         } else
 156                 free(i);
 157
 158         unit_add_to_dbus_queue(u);
 159         return 0;
 160
 161 fail:
 162         free(s);
 163         free(i);
 164
 165         return r;
 166 }
 167
 168 int unit_choose_id(Unit *u, const char *name) {
 169         char *s, *t = NULL;
 170
 171         assert(u);
 172         assert(name);
 173
 174         if (unit_name_is_template(name)) {
 175
 176                 if (!u->meta.instance)
 177                         return -EINVAL;
 178
 179                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 180                         return -ENOMEM;
 181
 182                 name = t;
 183         }
 184
 185         /* Selects one of the names of this unit as the id */
 186         s = set_get(u->meta.names, (char*) name);
 187         free(t);
 188
 189         if (!s)
 190                 return -ENOENT;
 191
 192         u->meta.id = s;
 193         unit_add_to_dbus_queue(u);
 194
 195         return 0;
 196 }
 197
 198 int unit_set_description(Unit *u, const char *description) {
 199         char *s;
 200
 201         assert(u);
 202
 203         if (!(s = strdup(description)))
 204                 return -ENOMEM;
 205
 206         free(u->meta.description);
 207         u->meta.description = s;
 208
 209         unit_add_to_dbus_queue(u);
 210         return 0;
 211 }
 212
 213 bool unit_check_gc(Unit *u) {
 214         assert(u);
 215
 216         if (u->meta.load_state == UNIT_STUB)
 217                 return true;
 218
 219         if (UNIT_VTABLE(u)->no_gc)
 220                 return true;
 221
 222         if (u->meta.job)
 223                 return true;
 224
 225         if (unit_active_state(u) != UNIT_INACTIVE)
 226                 return true;
 227
 228         if (UNIT_VTABLE(u)->check_gc)
 229                 if (UNIT_VTABLE(u)->check_gc(u))
 230                         return true;
 231
 232         return false;
 233 }
 234
 235 void unit_add_to_load_queue(Unit *u) {
 236         assert(u);
 237         assert(u->meta.type != _UNIT_TYPE_INVALID);
 238
 239         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 240                 return;
 241
 242         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 243         u->meta.in_load_queue = true;
 244 }
 245
 246 void unit_add_to_cleanup_queue(Unit *u) {
 247         assert(u);
 248
 249         if (u->meta.in_cleanup_queue)
 250                 return;
 251
 252         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 253         u->meta.in_cleanup_queue = true;
 254 }
 255
 256 void unit_add_to_gc_queue(Unit *u) {
 257         assert(u);
 258
 259         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 260                 return;
 261
 262         if (unit_check_gc(u))
 263                 return;
 264
 265         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 266         u->meta.in_gc_queue = true;
 267
 268         u->meta.manager->n_in_gc_queue ++;
 269
 270         if (u->meta.manager->gc_queue_timestamp <= 0)
 271                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 272 }
 273
 274 void unit_add_to_dbus_queue(Unit *u) {
 275         assert(u);
 276         assert(u->meta.type != _UNIT_TYPE_INVALID);
 277
 278         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 279                 return;
 280
 281         if (set_isempty(u->meta.manager->subscribed)) {
 282                 u->meta.sent_dbus_new_signal = true;
 283                 return;
 284         }
 285
 286         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 287         u->meta.in_dbus_queue = true;
 288 }
 289
 290 static void bidi_set_free(Unit *u, Set *s) {
 291         Iterator i;
 292         Unit *other;
 293
 294         assert(u);
 295
 296         /* Frees the set and makes sure we are dropped from the
 297          * inverse pointers */
 298
 299         SET_FOREACH(other, s, i) {
 300                 UnitDependency d;
 301
 302                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 303                         set_remove(other->meta.dependencies[d], u);
 304
 305                 unit_add_to_gc_queue(other);
 306         }
 307
 308         set_free(s);
 309 }
 310
 311 void unit_free(Unit *u) {
 312         UnitDependency d;
 313         Iterator i;
 314         char *t;
 315
 316         assert(u);
 317
 318         bus_unit_send_removed_signal(u);
 319
 320         /* Detach from next 'bigger' objects */
 321         SET_FOREACH(t, u->meta.names, i)
 322                 hashmap_remove_value(u->meta.manager->units, t, u);
 323
 324         if (u->meta.type != _UNIT_TYPE_INVALID)
 325                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 326
 327         if (u->meta.in_load_queue)
 328                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 329
 330         if (u->meta.in_dbus_queue)
 331                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 332
 333         if (u->meta.in_cleanup_queue)
 334                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 335
 336         if (u->meta.in_gc_queue) {
 337                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 338                 u->meta.manager->n_in_gc_queue--;
 339         }
 340
 341         /* Free data and next 'smaller' objects */
 342         if (u->meta.job)
 343                 job_free(u->meta.job);
 344
 345         if (u->meta.load_state != UNIT_STUB)
 346                 if (UNIT_VTABLE(u)->done)
 347                         UNIT_VTABLE(u)->done(u);
 348
 349         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 350
 351         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 352                 bidi_set_free(u, u->meta.dependencies[d]);
 353
 354         free(u->meta.description);
 355         free(u->meta.fragment_path);
 356
 357         while ((t = set_steal_first(u->meta.names)))
 358                 free(t);
 359         set_free(u->meta.names);
 360
 361         free(u->meta.instance);
 362
 363         free(u);
 364 }
 365
 366 UnitActiveState unit_active_state(Unit *u) {
 367         assert(u);
 368
 369         if (u->meta.load_state != UNIT_LOADED)
 370                 return UNIT_INACTIVE;
 371
 372         return UNIT_VTABLE(u)->active_state(u);
 373 }
 374
 375 const char* unit_sub_state_to_string(Unit *u) {
 376         assert(u);
 377
 378         return UNIT_VTABLE(u)->sub_state_to_string(u);
 379 }
 380
 381 static void complete_move(Set **s, Set **other) {
 382         assert(s);
 383         assert(other);
 384
 385         if (!*other)
 386                 return;
 387
 388         if (*s)
 389                 set_move(*s, *other);
 390         else {
 391                 *s = *other;
 392                 *other = NULL;
 393         }
 394 }
 395
 396 static void merge_names(Unit *u, Unit *other) {
 397         char *t;
 398         Iterator i;
 399
 400         assert(u);
 401         assert(other);
 402
 403         complete_move(&u->meta.names, &other->meta.names);
 404
 405         while ((t = set_steal_first(other->meta.names)))
 406                 free(t);
 407
 408         set_free(other->meta.names);
 409         other->meta.names = NULL;
 410         other->meta.id = NULL;
 411
 412         SET_FOREACH(t, u->meta.names, i)
 413                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 414 }
 415
 416 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 417         Iterator i;
 418         Unit *back;
 419         int r;
 420
 421         assert(u);
 422         assert(other);
 423         assert(d < _UNIT_DEPENDENCY_MAX);
 424
 425         SET_FOREACH(back, other->meta.dependencies[d], i) {
 426                 UnitDependency k;
 427
 428                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 429                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 430
 431                                 if (r == -EEXIST)
 432                                         set_remove(back->meta.dependencies[k], other);
 433                                 else
 434                                         assert(r == -ENOENT);
 435                         }
 436         }
 437
 438         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 439
 440         set_free(other->meta.dependencies[d]);
 441         other->meta.dependencies[d] = NULL;
 442 }
 443
 444 int unit_merge(Unit *u, Unit *other) {
 445         UnitDependency d;
 446
 447         assert(u);
 448         assert(other);
 449         assert(u->meta.manager == other->meta.manager);
 450         assert(u->meta.type != _UNIT_TYPE_INVALID);
 451
 452         other = unit_follow_merge(other);
 453
 454         if (other == u)
 455                 return 0;
 456
 457         if (u->meta.type != other->meta.type)
 458                 return -EINVAL;
 459
 460         if (!streq_ptr(u->meta.instance, other->meta.instance))
 461                 return -EINVAL;
 462
 463         if (other->meta.load_state != UNIT_STUB &&
 464             other->meta.load_state != UNIT_FAILED)
 465                 return -EEXIST;
 466
 467         if (other->meta.job)
 468                 return -EEXIST;
 469
 470         if (unit_active_state(other) != UNIT_INACTIVE)
 471                 return -EEXIST;
 472
 473         /* Merge names */
 474         merge_names(u, other);
 475
 476         /* Merge dependencies */
 477         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 478                 merge_dependencies(u, other, d);
 479
 480         other->meta.load_state = UNIT_MERGED;
 481         other->meta.merged_into = u;
 482
 483         /* If there is still some data attached to the other node, we
 484          * don't need it anymore, and can free it. */
 485         if (other->meta.load_state != UNIT_STUB)
 486                 if (UNIT_VTABLE(other)->done)
 487                         UNIT_VTABLE(other)->done(other);
 488
 489         unit_add_to_dbus_queue(u);
 490         unit_add_to_cleanup_queue(other);
 491
 492         return 0;
 493 }
 494
 495 int unit_merge_by_name(Unit *u, const char *name) {
 496         Unit *other;
 497         int r;
 498         char *s = NULL;
 499
 500         assert(u);
 501         assert(name);
 502
 503         if (unit_name_is_template(name)) {
 504                 if (!u->meta.instance)
 505                         return -EINVAL;
 506
 507                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 508                         return -ENOMEM;
 509
 510                 name = s;
 511         }
 512
 513         if (!(other = manager_get_unit(u->meta.manager, name)))
 514                 r = unit_add_name(u, name);
 515         else
 516                 r = unit_merge(u, other);
 517
 518         free(s);
 519         return r;
 520 }
 521
 522 Unit* unit_follow_merge(Unit *u) {
 523         assert(u);
 524
 525         while (u->meta.load_state == UNIT_MERGED)
 526                 assert_se(u = u->meta.merged_into);
 527
 528         return u;
 529 }
 530
 531 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 532         int r;
 533
 534         assert(u);
 535         assert(c);
 536
 537         if (c->std_output != EXEC_OUTPUT_KMSG && c->std_output != EXEC_OUTPUT_SYSLOG)
 538                 return 0;
 539
 540         /* If syslog or kernel logging is requested, make sure our own
 541          * logging daemon is run first. */
 542
 543         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 544                 return r;
 545
 546         if (u->meta.manager->running_as != MANAGER_SESSION)
 547                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 548                         return r;
 549
 550         return 0;
 551 }
 552
 553 const char *unit_description(Unit *u) {
 554         assert(u);
 555
 556         if (u->meta.description)
 557                 return u->meta.description;
 558
 559         return u->meta.id;
 560 }
 561
 562 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 563         char *t;
 564         UnitDependency d;
 565         Iterator i;
 566         char *p2;
 567         const char *prefix2;
 568         CGroupBonding *b;
 569         char
 570                 timestamp1[FORMAT_TIMESTAMP_MAX],
 571                 timestamp2[FORMAT_TIMESTAMP_MAX],
 572                 timestamp3[FORMAT_TIMESTAMP_MAX],
 573                 timestamp4[FORMAT_TIMESTAMP_MAX];
 574
 575         assert(u);
 576         assert(u->meta.type >= 0);
 577
 578         if (!prefix)
 579                 prefix = "";
 580         p2 = strappend(prefix, "\t");
 581         prefix2 = p2 ? p2 : prefix;
 582
 583         fprintf(f,
 584                 "%s-> Unit %s:\n"
 585                 "%s\tDescription: %s\n"
 586                 "%s\tInstance: %s\n"
 587                 "%s\tUnit Load State: %s\n"
 588                 "%s\tUnit Active State: %s\n"
 589                 "%s\tInactive Exit Timestamp: %s\n"
 590                 "%s\tActive Enter Timestamp: %s\n"
 591                 "%s\tActive Exit Timestamp: %s\n"
 592                 "%s\tInactive Enter Timestamp: %s\n"
 593                 "%s\tGC Check Good: %s\n",
 594                 prefix, u->meta.id,
 595                 prefix, unit_description(u),
 596                 prefix, strna(u->meta.instance),
 597                 prefix, unit_load_state_to_string(u->meta.load_state),
 598                 prefix, unit_active_state_to_string(unit_active_state(u)),
 599                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp)),
 600                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp)),
 601                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp)),
 602                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp)),
 603                 prefix, yes_no(unit_check_gc(u)));
 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         usec_t 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         ts = now(CLOCK_REALTIME);
 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         if (u->meta.job) {
 954
 955                 if (u->meta.job->state == JOB_WAITING)
 956
 957                         /* So we reached a different state for this
 958                          * job. Let's see if we can run it now if it
 959                          * failed previously due to EAGAIN. */
 960                         job_add_to_run_queue(u->meta.job);
 961
 962                 else {
 963                         assert(u->meta.job->state == JOB_RUNNING);
 964
 965                         /* Let's check whether this state change
 966                          * constitutes a finished job, or maybe
 967                          * cotradicts a running job and hence needs to
 968                          * 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 (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 (ns == UNIT_ACTIVE)
 988                                         job_finish_and_invalidate(u->meta.job, true);
 989                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_ACTIVE_RELOADING) {
 990                                         unexpected = true;
 991                                         job_finish_and_invalidate(u->meta.job, false);
 992                                 }
 993
 994                                 break;
 995
 996                         case JOB_STOP:
 997                         case JOB_RESTART:
 998                         case JOB_TRY_RESTART:
 999
1000                                 if (ns == UNIT_INACTIVE)
1001                                         job_finish_and_invalidate(u->meta.job, true);
1002                                 else if (ns != UNIT_DEACTIVATING) {
1003                                         unexpected = true;
1004                                         job_finish_and_invalidate(u->meta.job, false);
1005                                 }
1006
1007                                 break;
1008
1009                         default:
1010                                 assert_not_reached("Job type unknown");
1011                         }
1012                 }
1013         }
1014
1015         /* If this state change happened without being requested by a
1016          * job, then let's retroactively start or stop dependencies */
1017
1018         if (unexpected) {
1019                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1020                         retroactively_start_dependencies(u);
1021                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1022                         retroactively_stop_dependencies(u);
1023         }
1024
1025         /* Some names are special */
1026         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1027                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1028                         /* The bus just might have become available,
1029                          * hence try to connect to it, if we aren't
1030                          * yet connected. */
1031                         bus_init_system(u->meta.manager);
1032                         bus_init_api(u->meta.manager);
1033                 }
1034
1035                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1036                         /* The syslog daemon just might have become
1037                          * available, hence try to connect to it, if
1038                          * we aren't yet connected. */
1039                         log_open();
1040
1041                 if (u->meta.type == UNIT_MOUNT)
1042                         /* Another directory became available, let's
1043                          * check if that is enough to write our utmp
1044                          * entry. */
1045                         manager_write_utmp_reboot(u->meta.manager);
1046
1047                 if (u->meta.type == UNIT_TARGET)
1048                         /* A target got activated, maybe this is a runlevel? */
1049                         manager_write_utmp_runlevel(u->meta.manager, u);
1050
1051         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1052
1053                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1054                         /* The syslog daemon might just have
1055                          * terminated, hence try to disconnect from
1056                          * it. */
1057                         log_close_syslog();
1058
1059                 /* We don't care about D-Bus here, since we'll get an
1060                  * asynchronous notification for it anyway. */
1061         }
1062
1063         /* Maybe we finished startup and are now ready for being
1064          * stopped because unneeded? */
1065         unit_check_uneeded(u);
1066
1067         unit_add_to_dbus_queue(u);
1068         unit_add_to_gc_queue(u);
1069 }
1070
1071 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1072         struct epoll_event ev;
1073
1074         assert(u);
1075         assert(fd >= 0);
1076         assert(w);
1077         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1078
1079         zero(ev);
1080         ev.data.ptr = w;
1081         ev.events = events;
1082
1083         if (epoll_ctl(u->meta.manager->epoll_fd,
1084                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1085                       fd,
1086                       &ev) < 0)
1087                 return -errno;
1088
1089         w->fd = fd;
1090         w->type = WATCH_FD;
1091         w->data.unit = u;
1092
1093         return 0;
1094 }
1095
1096 void unit_unwatch_fd(Unit *u, Watch *w) {
1097         assert(u);
1098         assert(w);
1099
1100         if (w->type == WATCH_INVALID)
1101                 return;
1102
1103         assert(w->type == WATCH_FD);
1104         assert(w->data.unit == u);
1105         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1106
1107         w->fd = -1;
1108         w->type = WATCH_INVALID;
1109         w->data.unit = NULL;
1110 }
1111
1112 int unit_watch_pid(Unit *u, pid_t pid) {
1113         assert(u);
1114         assert(pid >= 1);
1115
1116         /* Watch a specific PID. We only support one unit watching
1117          * each PID for now. */
1118
1119         return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1120 }
1121
1122 void unit_unwatch_pid(Unit *u, pid_t pid) {
1123         assert(u);
1124         assert(pid >= 1);
1125
1126         hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1127 }
1128
1129 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1130         struct itimerspec its;
1131         int flags, fd;
1132         bool ours;
1133
1134         assert(u);
1135         assert(w);
1136         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1137
1138         /* This will try to reuse the old timer if there is one */
1139
1140         if (w->type == WATCH_TIMER) {
1141                 ours = false;
1142                 fd = w->fd;
1143         } else {
1144                 ours = true;
1145                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1146                         return -errno;
1147         }
1148
1149         zero(its);
1150
1151         if (delay <= 0) {
1152                 /* Set absolute time in the past, but not 0, since we
1153                  * don't want to disarm the timer */
1154                 its.it_value.tv_sec = 0;
1155                 its.it_value.tv_nsec = 1;
1156
1157                 flags = TFD_TIMER_ABSTIME;
1158         } else {
1159                 timespec_store(&its.it_value, delay);
1160                 flags = 0;
1161         }
1162
1163         /* This will also flush the elapse counter */
1164         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1165                 goto fail;
1166
1167         if (w->type == WATCH_INVALID) {
1168                 struct epoll_event ev;
1169
1170                 zero(ev);
1171                 ev.data.ptr = w;
1172                 ev.events = EPOLLIN;
1173
1174                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1175                         goto fail;
1176         }
1177
1178         w->fd = fd;
1179         w->type = WATCH_TIMER;
1180         w->data.unit = u;
1181
1182         return 0;
1183
1184 fail:
1185         if (ours)
1186                 close_nointr_nofail(fd);
1187
1188         return -errno;
1189 }
1190
1191 void unit_unwatch_timer(Unit *u, Watch *w) {
1192         assert(u);
1193         assert(w);
1194
1195         if (w->type == WATCH_INVALID)
1196                 return;
1197
1198         assert(w->type == WATCH_TIMER && w->data.unit == u);
1199
1200         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1201         close_nointr_nofail(w->fd);
1202
1203         w->fd = -1;
1204         w->type = WATCH_INVALID;
1205         w->data.unit = NULL;
1206 }
1207
1208 bool unit_job_is_applicable(Unit *u, JobType j) {
1209         assert(u);
1210         assert(j >= 0 && j < _JOB_TYPE_MAX);
1211
1212         switch (j) {
1213
1214         case JOB_VERIFY_ACTIVE:
1215         case JOB_START:
1216                 return true;
1217
1218         case JOB_STOP:
1219         case JOB_RESTART:
1220         case JOB_TRY_RESTART:
1221                 return unit_can_start(u);
1222
1223         case JOB_RELOAD:
1224                 return unit_can_reload(u);
1225
1226         case JOB_RELOAD_OR_START:
1227                 return unit_can_reload(u) && unit_can_start(u);
1228
1229         default:
1230                 assert_not_reached("Invalid job type");
1231         }
1232 }
1233
1234 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1235
1236         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1237                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1238                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1239                 [UNIT_WANTS] = UNIT_WANTED_BY,
1240                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1241                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1242                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1243                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1244                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1245                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1246                 [UNIT_BEFORE] = UNIT_AFTER,
1247                 [UNIT_AFTER] = UNIT_BEFORE,
1248                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1249                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1250         };
1251         int r, q = 0, v = 0, w = 0;
1252
1253         assert(u);
1254         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1255         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1256         assert(other);
1257
1258         /* We won't allow dependencies on ourselves. We will not
1259          * consider them an error however. */
1260         if (u == other)
1261                 return 0;
1262
1263         if (UNIT_VTABLE(u)->no_requires &&
1264             (d == UNIT_REQUIRES ||
1265              d == UNIT_REQUIRES_OVERRIDABLE ||
1266              d == UNIT_REQUISITE ||
1267              d == UNIT_REQUISITE_OVERRIDABLE)) {
1268                     return -EINVAL;
1269         }
1270
1271         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1272             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1273                 return r;
1274
1275         if (add_reference)
1276                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1277                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1278                         return r;
1279
1280         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1281                 return q;
1282
1283         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1284                 r = v;
1285                 goto fail;
1286         }
1287
1288         if (add_reference) {
1289                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1290                         r = w;
1291                         goto fail;
1292                 }
1293
1294                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1295                         goto fail;
1296         }
1297
1298         unit_add_to_dbus_queue(u);
1299         return 0;
1300
1301 fail:
1302         if (q > 0)
1303                 set_remove(u->meta.dependencies[d], other);
1304
1305         if (v > 0)
1306                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1307
1308         if (w > 0)
1309                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1310
1311         return r;
1312 }
1313
1314 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1315         char *s;
1316
1317         assert(u);
1318         assert(name || path);
1319
1320         if (!name)
1321                 name = file_name_from_path(path);
1322
1323         if (!unit_name_is_template(name)) {
1324                 *p = NULL;
1325                 return name;
1326         }
1327
1328         if (u->meta.instance)
1329                 s = unit_name_replace_instance(name, u->meta.instance);
1330         else {
1331                 char *i;
1332
1333                 if (!(i = unit_name_to_prefix(u->meta.id)))
1334                         return NULL;
1335
1336                 s = unit_name_replace_instance(name, i);
1337                 free(i);
1338         }
1339
1340         if (!s)
1341                 return NULL;
1342
1343         *p = s;
1344         return s;
1345 }
1346
1347 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1348         Unit *other;
1349         int r;
1350         char *s;
1351
1352         assert(u);
1353         assert(name || path);
1354
1355         if (!(name = resolve_template(u, name, path, &s)))
1356                 return -ENOMEM;
1357
1358         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1359                 goto finish;
1360
1361         r = unit_add_dependency(u, d, other, add_reference);
1362
1363 finish:
1364         free(s);
1365         return r;
1366 }
1367
1368 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1369         Unit *other;
1370         int r;
1371         char *s;
1372
1373         assert(u);
1374         assert(name || path);
1375
1376         if (!(name = resolve_template(u, name, path, &s)))
1377                 return -ENOMEM;
1378
1379         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1380                 goto finish;
1381
1382         r = unit_add_dependency(other, d, u, add_reference);
1383
1384 finish:
1385         free(s);
1386         return r;
1387 }
1388
1389 int set_unit_path(const char *p) {
1390         char *cwd, *c;
1391         int r;
1392
1393         /* This is mostly for debug purposes */
1394
1395         if (path_is_absolute(p)) {
1396                 if (!(c = strdup(p)))
1397                         return -ENOMEM;
1398         } else {
1399                 if (!(cwd = get_current_dir_name()))
1400                         return -errno;
1401
1402                 r = asprintf(&c, "%s/%s", cwd, p);
1403                 free(cwd);
1404
1405                 if (r < 0)
1406                         return -ENOMEM;
1407         }
1408
1409         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1410                 r = -errno;
1411                 free(c);
1412                 return r;
1413         }
1414
1415         return 0;
1416 }
1417
1418 char *unit_dbus_path(Unit *u) {
1419         char *p, *e;
1420
1421         assert(u);
1422
1423         if (!(e = bus_path_escape(u->meta.id)))
1424                 return NULL;
1425
1426         if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
1427                 free(e);
1428                 return NULL;
1429         }
1430
1431         free(e);
1432         return p;
1433 }
1434
1435 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1436         CGroupBonding *l;
1437         int r;
1438
1439         assert(u);
1440         assert(b);
1441         assert(b->path);
1442
1443         /* Ensure this hasn't been added yet */
1444         assert(!b->unit);
1445
1446         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1447         LIST_PREPEND(CGroupBonding, by_path, l, b);
1448
1449         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1450                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1451                 return r;
1452         }
1453
1454         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1455         b->unit = u;
1456
1457         return 0;
1458 }
1459
1460 static char *default_cgroup_path(Unit *u) {
1461         char *p;
1462         int r;
1463
1464         assert(u);
1465
1466         if (u->meta.instance) {
1467                 char *t;
1468
1469                 if (!(t = unit_name_template(u->meta.id)))
1470                         return NULL;
1471
1472                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1473                 free(t);
1474         } else
1475                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1476
1477         return r < 0 ? NULL : p;
1478 }
1479
1480 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1481         size_t n;
1482         char *controller = NULL, *path = NULL;
1483         CGroupBonding *b = NULL;
1484         int r;
1485
1486         assert(u);
1487         assert(name);
1488
1489         /* Detect controller name */
1490         n = strcspn(name, ":");
1491
1492         if (name[n] == 0 ||
1493             (name[n] == ':' && name[n+1] == 0)) {
1494
1495                 /* Only controller name, no path? */
1496
1497                 if (!(path = default_cgroup_path(u)))
1498                         return -ENOMEM;
1499
1500         } else {
1501                 const char *p;
1502
1503                 /* Controller name, and path. */
1504                 p = name+n+1;
1505
1506                 if (!path_is_absolute(p))
1507                         return -EINVAL;
1508
1509                 if (!(path = strdup(p)))
1510                         return -ENOMEM;
1511         }
1512
1513         if (n > 0)
1514                 controller = strndup(name, n);
1515         else
1516                 controller = strdup(u->meta.manager->cgroup_controller);
1517
1518         if (!controller) {
1519                 r = -ENOMEM;
1520                 goto fail;
1521         }
1522
1523         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1524                 r = -EEXIST;
1525                 goto fail;
1526         }
1527
1528         if (!(b = new0(CGroupBonding, 1))) {
1529                 r = -ENOMEM;
1530                 goto fail;
1531         }
1532
1533         b->controller = controller;
1534         b->path = path;
1535         b->only_us = false;
1536         b->clean_up = false;
1537
1538         if ((r = unit_add_cgroup(u, b)) < 0)
1539                 goto fail;
1540
1541         return 0;
1542
1543 fail:
1544         free(path);
1545         free(controller);
1546         free(b);
1547
1548         return r;
1549 }
1550
1551 int unit_add_default_cgroup(Unit *u) {
1552         CGroupBonding *b;
1553         int r = -ENOMEM;
1554
1555         assert(u);
1556
1557         /* Adds in the default cgroup data, if it wasn't specified yet */
1558
1559         if (unit_get_default_cgroup(u))
1560                 return 0;
1561
1562         if (!(b = new0(CGroupBonding, 1)))
1563                 return -ENOMEM;
1564
1565         if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
1566                 goto fail;
1567
1568         if (!(b->path = default_cgroup_path(u)))
1569                 goto fail;
1570
1571         b->clean_up = true;
1572         b->only_us = true;
1573
1574         if ((r = unit_add_cgroup(u, b)) < 0)
1575                 goto fail;
1576
1577         return 0;
1578
1579 fail:
1580         free(b->path);
1581         free(b->controller);
1582         free(b);
1583
1584         return r;
1585 }
1586
1587 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1588         assert(u);
1589
1590         return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
1591 }
1592
1593 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1594         char *t;
1595         int r;
1596
1597         assert(u);
1598         assert(type);
1599         assert(_found);
1600
1601         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1602                 return -ENOMEM;
1603
1604         assert(!unit_has_name(u, t));
1605
1606         r = manager_load_unit(u->meta.manager, t, NULL, _found);
1607         free(t);
1608
1609         assert(r < 0 || *_found != u);
1610
1611         return r;
1612 }
1613
1614 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1615         Unit *found;
1616         char *t;
1617
1618         assert(u);
1619         assert(type);
1620         assert(_found);
1621
1622         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1623                 return -ENOMEM;
1624
1625         assert(!unit_has_name(u, t));
1626
1627         found = manager_get_unit(u->meta.manager, t);
1628         free(t);
1629
1630         if (!found)
1631                 return -ENOENT;
1632
1633         *_found = found;
1634         return 0;
1635 }
1636
1637 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1638         Unit *u = userdata;
1639         assert(u);
1640
1641         return unit_name_to_prefix_and_instance(u->meta.id);
1642 }
1643
1644 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1645         Unit *u = userdata;
1646         assert(u);
1647
1648         return unit_name_to_prefix(u->meta.id);
1649 }
1650
1651 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1652         Unit *u = userdata;
1653         char *p, *r;
1654
1655         assert(u);
1656
1657         if (!(p = unit_name_to_prefix(u->meta.id)))
1658                 return NULL;
1659
1660         r = unit_name_unescape(p);
1661         free(p);
1662
1663         return r;
1664 }
1665
1666 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1667         Unit *u = userdata;
1668         assert(u);
1669
1670         if (u->meta.instance)
1671                 return unit_name_unescape(u->meta.instance);
1672
1673         return strdup("");
1674 }
1675
1676 char *unit_name_printf(Unit *u, const char* format) {
1677
1678         /*
1679          * This will use the passed string as format string and
1680          * replace the following specifiers:
1681          *
1682          * %n: the full id of the unit                 (foo@bar.waldo)
1683          * %N: the id of the unit without the suffix   (foo@bar)
1684          * %p: the prefix                              (foo)
1685          * %i: the instance                            (bar)
1686          */
1687
1688         const Specifier table[] = {
1689                 { 'n', specifier_string,              u->meta.id },
1690                 { 'N', specifier_prefix_and_instance, NULL },
1691                 { 'p', specifier_prefix,              NULL },
1692                 { 'i', specifier_string,              u->meta.instance },
1693                 { 0, NULL, NULL }
1694         };
1695
1696         assert(u);
1697         assert(format);
1698
1699         return specifier_printf(format, table, u);
1700 }
1701
1702 char *unit_full_printf(Unit *u, const char *format) {
1703
1704         /* This is similar to unit_name_printf() but also supports
1705          * unescaping */
1706
1707         const Specifier table[] = {
1708                 { 'n', specifier_string,              u->meta.id },
1709                 { 'N', specifier_prefix_and_instance, NULL },
1710                 { 'p', specifier_prefix,              NULL },
1711                 { 'P', specifier_prefix_unescaped,    NULL },
1712                 { 'i', specifier_string,              u->meta.instance },
1713                 { 'I', specifier_instance_unescaped,  NULL },
1714                 { 0, NULL, NULL }
1715         };
1716
1717         assert(u);
1718         assert(format);
1719
1720         return specifier_printf(format, table, u);
1721 }
1722
1723 char **unit_full_printf_strv(Unit *u, char **l) {
1724         size_t n;
1725         char **r, **i, **j;
1726
1727         /* Applies unit_full_printf to every entry in l */
1728
1729         assert(u);
1730
1731         n = strv_length(l);
1732         if (!(r = new(char*, n+1)))
1733                 return NULL;
1734
1735         for (i = l, j = r; *i; i++, j++)
1736                 if (!(*j = unit_full_printf(u, *i)))
1737                         goto fail;
1738
1739         *j = NULL;
1740         return r;
1741
1742 fail:
1743         j--;
1744         while (j >= r)
1745                 free(*j);
1746
1747         free(r);
1748
1749         return NULL;
1750 }
1751
1752 int unit_watch_bus_name(Unit *u, const char *name) {
1753         assert(u);
1754         assert(name);
1755
1756         /* Watch a specific name on the bus. We only support one unit
1757          * watching each name for now. */
1758
1759         return hashmap_put(u->meta.manager->watch_bus, name, u);
1760 }
1761
1762 void unit_unwatch_bus_name(Unit *u, const char *name) {
1763         assert(u);
1764         assert(name);
1765
1766         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1767 }
1768
1769 bool unit_can_serialize(Unit *u) {
1770         assert(u);
1771
1772         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1773 }
1774
1775 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1776         int r;
1777
1778         assert(u);
1779         assert(f);
1780         assert(fds);
1781
1782         if (!unit_can_serialize(u))
1783                 return 0;
1784
1785         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1786                 return r;
1787
1788         /* End marker */
1789         fputc('\n', f);
1790         return 0;
1791 }
1792
1793 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1794         va_list ap;
1795
1796         assert(u);
1797         assert(f);
1798         assert(key);
1799         assert(format);
1800
1801         fputs(key, f);
1802         fputc('=', f);
1803
1804         va_start(ap, format);
1805         vfprintf(f, format, ap);
1806         va_end(ap);
1807
1808         fputc('\n', f);
1809 }
1810
1811 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1812         assert(u);
1813         assert(f);
1814         assert(key);
1815         assert(value);
1816
1817         fprintf(f, "%s=%s\n", key, value);
1818 }
1819
1820 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1821         int r;
1822
1823         assert(u);
1824         assert(f);
1825         assert(fds);
1826
1827         if (!unit_can_serialize(u))
1828                 return 0;
1829
1830         for (;;) {
1831                 char line[1024], *l, *v;
1832                 size_t k;
1833
1834                 if (!fgets(line, sizeof(line), f)) {
1835                         if (feof(f))
1836                                 return 0;
1837                         return -errno;
1838                 }
1839
1840                 l = strstrip(line);
1841
1842                 /* End marker */
1843                 if (l[0] == 0)
1844                         return 0;
1845
1846                 k = strcspn(l, "=");
1847
1848                 if (l[k] == '=') {
1849                         l[k] = 0;
1850                         v = l+k+1;
1851                 } else
1852                         v = l+k;
1853
1854                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1855                         return r;
1856         }
1857 }
1858
1859 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1860         Unit *device;
1861         char *e;
1862         int r;
1863
1864         assert(u);
1865
1866         if (!what)
1867                 return 0;
1868
1869         /* Adds in links to the device node that this unit is based on */
1870
1871         if (!is_device_path(what))
1872                 return 0;
1873
1874         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1875                 return -ENOMEM;
1876
1877         r = manager_load_unit(u->meta.manager, e, NULL, &device);
1878         free(e);
1879
1880         if (r < 0)
1881                 return r;
1882
1883         if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
1884                 return r;
1885
1886         if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
1887                 return r;
1888
1889         if (wants)
1890                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1891                         return r;
1892
1893         return 0;
1894 }
1895
1896 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
1897         [UNIT_SERVICE] = "service",
1898         [UNIT_TIMER] = "timer",
1899         [UNIT_SOCKET] = "socket",
1900         [UNIT_TARGET] = "target",
1901         [UNIT_DEVICE] = "device",
1902         [UNIT_MOUNT] = "mount",
1903         [UNIT_AUTOMOUNT] = "automount",
1904         [UNIT_SNAPSHOT] = "snapshot",
1905         [UNIT_SWAP] = "swap"
1906 };
1907
1908 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
1909
1910 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
1911         [UNIT_STUB] = "stub",
1912         [UNIT_LOADED] = "loaded",
1913         [UNIT_FAILED] = "failed",
1914         [UNIT_MERGED] = "merged"
1915 };
1916
1917 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
1918
1919 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
1920         [UNIT_ACTIVE] = "active",
1921         [UNIT_INACTIVE] = "inactive",
1922         [UNIT_ACTIVATING] = "activating",
1923         [UNIT_DEACTIVATING] = "deactivating"
1924 };
1925
1926 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
1927
1928 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
1929         [UNIT_REQUIRES] = "Requires",
1930         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
1931         [UNIT_WANTS] = "Wants",
1932         [UNIT_REQUISITE] = "Requisite",
1933         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
1934         [UNIT_REQUIRED_BY] = "RequiredBy",
1935         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
1936         [UNIT_WANTED_BY] = "WantedBy",
1937         [UNIT_CONFLICTS] = "Conflicts",
1938         [UNIT_BEFORE] = "Before",
1939         [UNIT_AFTER] = "After",
1940         [UNIT_REFERENCES] = "References",
1941         [UNIT_REFERENCED_BY] = "ReferencedBy"
1942 };
1943
1944 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
1945
1946 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
1947         [KILL_CONTROL_GROUP] = "control-group",
1948         [KILL_PROCESS_GROUP] = "process-group",
1949         [KILL_PROCESS] = "process",
1950         [KILL_NONE] = "none"
1951 };
1952
1953 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);