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