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 #include "special.h"
  42
  43 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  44         [UNIT_SERVICE] = &service_vtable,
  45         [UNIT_TIMER] = &timer_vtable,
  46         [UNIT_SOCKET] = &socket_vtable,
  47         [UNIT_TARGET] = &target_vtable,
  48         [UNIT_DEVICE] = &device_vtable,
  49         [UNIT_MOUNT] = &mount_vtable,
  50         [UNIT_AUTOMOUNT] = &automount_vtable,
  51         [UNIT_SNAPSHOT] = &snapshot_vtable,
  52         [UNIT_SWAP] = &swap_vtable,
  53         [UNIT_PATH] = &path_vtable
  54 };
  55
  56 Unit *unit_new(Manager *m) {
  57         Unit *u;
  58
  59         assert(m);
  60
  61         if (!(u = new0(Unit, 1)))
  62                 return NULL;
  63
  64         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  65                 free(u);
  66                 return NULL;
  67         }
  68
  69         u->meta.manager = m;
  70         u->meta.type = _UNIT_TYPE_INVALID;
  71         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  72         u->meta.default_dependencies = true;
  73
  74         return u;
  75 }
  76
  77 bool unit_has_name(Unit *u, const char *name) {
  78         assert(u);
  79         assert(name);
  80
  81         return !!set_get(u->meta.names, (char*) name);
  82 }
  83
  84 int unit_add_name(Unit *u, const char *text) {
  85         UnitType t;
  86         char *s = NULL, *i = NULL;
  87         int r;
  88
  89         assert(u);
  90         assert(text);
  91
  92         if (unit_name_is_template(text)) {
  93                 if (!u->meta.instance)
  94                         return -EINVAL;
  95
  96                 s = unit_name_replace_instance(text, u->meta.instance);
  97         } else
  98                 s = strdup(text);
  99
 100         if (!s)
 101                 return -ENOMEM;
 102
 103         if (!unit_name_is_valid(s)) {
 104                 r = -EINVAL;
 105                 goto fail;
 106         }
 107
 108         assert_se((t = unit_name_to_type(s)) >= 0);
 109
 110         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 111                 r = -EINVAL;
 112                 goto fail;
 113         }
 114
 115         if ((r = unit_name_to_instance(s, &i)) < 0)
 116                 goto fail;
 117
 118         if (i && unit_vtable[t]->no_instances)
 119                 goto fail;
 120
 121         if (u->meta.type != _UNIT_TYPE_INVALID && !streq_ptr(u->meta.instance, i)) {
 122                 r = -EINVAL;
 123                 goto fail;
 124         }
 125
 126         if (unit_vtable[t]->no_alias &&
 127             !set_isempty(u->meta.names) &&
 128             !set_get(u->meta.names, s)) {
 129                 r = -EEXIST;
 130                 goto fail;
 131         }
 132
 133         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 134                 r = -E2BIG;
 135                 goto fail;
 136         }
 137
 138         if ((r = set_put(u->meta.names, s)) < 0) {
 139                 if (r == -EEXIST)
 140                         r = 0;
 141                 goto fail;
 142         }
 143
 144         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 145                 set_remove(u->meta.names, s);
 146                 goto fail;
 147         }
 148
 149         if (u->meta.type == _UNIT_TYPE_INVALID) {
 150
 151                 u->meta.type = t;
 152                 u->meta.id = s;
 153                 u->meta.instance = i;
 154
 155                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 156
 157                 if (UNIT_VTABLE(u)->init)
 158                         UNIT_VTABLE(u)->init(u);
 159         } else
 160                 free(i);
 161
 162         unit_add_to_dbus_queue(u);
 163         return 0;
 164
 165 fail:
 166         free(s);
 167         free(i);
 168
 169         return r;
 170 }
 171
 172 int unit_choose_id(Unit *u, const char *name) {
 173         char *s, *t = NULL;
 174
 175         assert(u);
 176         assert(name);
 177
 178         if (unit_name_is_template(name)) {
 179
 180                 if (!u->meta.instance)
 181                         return -EINVAL;
 182
 183                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 184                         return -ENOMEM;
 185
 186                 name = t;
 187         }
 188
 189         /* Selects one of the names of this unit as the id */
 190         s = set_get(u->meta.names, (char*) name);
 191         free(t);
 192
 193         if (!s)
 194                 return -ENOENT;
 195
 196         u->meta.id = s;
 197         unit_add_to_dbus_queue(u);
 198
 199         return 0;
 200 }
 201
 202 int unit_set_description(Unit *u, const char *description) {
 203         char *s;
 204
 205         assert(u);
 206
 207         if (!(s = strdup(description)))
 208                 return -ENOMEM;
 209
 210         free(u->meta.description);
 211         u->meta.description = s;
 212
 213         unit_add_to_dbus_queue(u);
 214         return 0;
 215 }
 216
 217 bool unit_check_gc(Unit *u) {
 218         assert(u);
 219
 220         if (u->meta.load_state == UNIT_STUB)
 221                 return true;
 222
 223         if (UNIT_VTABLE(u)->no_gc)
 224                 return true;
 225
 226         if (u->meta.job)
 227                 return true;
 228
 229         if (unit_active_state(u) != UNIT_INACTIVE)
 230                 return true;
 231
 232         if (UNIT_VTABLE(u)->check_gc)
 233                 if (UNIT_VTABLE(u)->check_gc(u))
 234                         return true;
 235
 236         return false;
 237 }
 238
 239 void unit_add_to_load_queue(Unit *u) {
 240         assert(u);
 241         assert(u->meta.type != _UNIT_TYPE_INVALID);
 242
 243         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 244                 return;
 245
 246         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 247         u->meta.in_load_queue = true;
 248 }
 249
 250 void unit_add_to_cleanup_queue(Unit *u) {
 251         assert(u);
 252
 253         if (u->meta.in_cleanup_queue)
 254                 return;
 255
 256         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 257         u->meta.in_cleanup_queue = true;
 258 }
 259
 260 void unit_add_to_gc_queue(Unit *u) {
 261         assert(u);
 262
 263         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 264                 return;
 265
 266         if (unit_check_gc(u))
 267                 return;
 268
 269         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 270         u->meta.in_gc_queue = true;
 271
 272         u->meta.manager->n_in_gc_queue ++;
 273
 274         if (u->meta.manager->gc_queue_timestamp <= 0)
 275                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 276 }
 277
 278 void unit_add_to_dbus_queue(Unit *u) {
 279         assert(u);
 280         assert(u->meta.type != _UNIT_TYPE_INVALID);
 281
 282         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 283                 return;
 284
 285         if (set_isempty(u->meta.manager->subscribed)) {
 286                 u->meta.sent_dbus_new_signal = true;
 287                 return;
 288         }
 289
 290         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 291         u->meta.in_dbus_queue = true;
 292 }
 293
 294 static void bidi_set_free(Unit *u, Set *s) {
 295         Iterator i;
 296         Unit *other;
 297
 298         assert(u);
 299
 300         /* Frees the set and makes sure we are dropped from the
 301          * inverse pointers */
 302
 303         SET_FOREACH(other, s, i) {
 304                 UnitDependency d;
 305
 306                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 307                         set_remove(other->meta.dependencies[d], u);
 308
 309                 unit_add_to_gc_queue(other);
 310         }
 311
 312         set_free(s);
 313 }
 314
 315 void unit_free(Unit *u) {
 316         UnitDependency d;
 317         Iterator i;
 318         char *t;
 319
 320         assert(u);
 321
 322         bus_unit_send_removed_signal(u);
 323
 324         if (u->meta.load_state != UNIT_STUB)
 325                 if (UNIT_VTABLE(u)->done)
 326                         UNIT_VTABLE(u)->done(u);
 327
 328         SET_FOREACH(t, u->meta.names, i)
 329                 hashmap_remove_value(u->meta.manager->units, t, u);
 330
 331         if (u->meta.job)
 332                 job_free(u->meta.job);
 333
 334         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 335                 bidi_set_free(u, u->meta.dependencies[d]);
 336
 337         if (u->meta.type != _UNIT_TYPE_INVALID)
 338                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 339
 340         if (u->meta.in_load_queue)
 341                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 342
 343         if (u->meta.in_dbus_queue)
 344                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 345
 346         if (u->meta.in_cleanup_queue)
 347                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 348
 349         if (u->meta.in_gc_queue) {
 350                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 351                 u->meta.manager->n_in_gc_queue--;
 352         }
 353
 354         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 355
 356         free(u->meta.description);
 357         free(u->meta.fragment_path);
 358
 359         set_free_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_MERGED)
 370                 return unit_active_state(unit_follow_merge(u));
 371
 372         /* After a reload it might happen that a unit is not correctly
 373          * loaded but still has a process around. That's why we won't
 374          * shortcut failed loading to UNIT_INACTIVE_MAINTENANCE. */
 375
 376         return UNIT_VTABLE(u)->active_state(u);
 377 }
 378
 379 const char* unit_sub_state_to_string(Unit *u) {
 380         assert(u);
 381
 382         return UNIT_VTABLE(u)->sub_state_to_string(u);
 383 }
 384
 385 static void complete_move(Set **s, Set **other) {
 386         assert(s);
 387         assert(other);
 388
 389         if (!*other)
 390                 return;
 391
 392         if (*s)
 393                 set_move(*s, *other);
 394         else {
 395                 *s = *other;
 396                 *other = NULL;
 397         }
 398 }
 399
 400 static void merge_names(Unit *u, Unit *other) {
 401         char *t;
 402         Iterator i;
 403
 404         assert(u);
 405         assert(other);
 406
 407         complete_move(&u->meta.names, &other->meta.names);
 408
 409         set_free_free(other->meta.names);
 410         other->meta.names = NULL;
 411         other->meta.id = NULL;
 412
 413         SET_FOREACH(t, u->meta.names, i)
 414                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 415 }
 416
 417 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 418         Iterator i;
 419         Unit *back;
 420         int r;
 421
 422         assert(u);
 423         assert(other);
 424         assert(d < _UNIT_DEPENDENCY_MAX);
 425
 426         SET_FOREACH(back, other->meta.dependencies[d], i) {
 427                 UnitDependency k;
 428
 429                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 430                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 431
 432                                 if (r == -EEXIST)
 433                                         set_remove(back->meta.dependencies[k], other);
 434                                 else
 435                                         assert(r == -ENOENT);
 436                         }
 437         }
 438
 439         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 440
 441         set_free(other->meta.dependencies[d]);
 442         other->meta.dependencies[d] = NULL;
 443 }
 444
 445 int unit_merge(Unit *u, Unit *other) {
 446         UnitDependency d;
 447
 448         assert(u);
 449         assert(other);
 450         assert(u->meta.manager == other->meta.manager);
 451         assert(u->meta.type != _UNIT_TYPE_INVALID);
 452
 453         other = unit_follow_merge(other);
 454
 455         if (other == u)
 456                 return 0;
 457
 458         if (u->meta.type != other->meta.type)
 459                 return -EINVAL;
 460
 461         if (!streq_ptr(u->meta.instance, other->meta.instance))
 462                 return -EINVAL;
 463
 464         if (other->meta.load_state != UNIT_STUB &&
 465             other->meta.load_state != UNIT_FAILED)
 466                 return -EEXIST;
 467
 468         if (other->meta.job)
 469                 return -EEXIST;
 470
 471         if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(other)))
 472                 return -EEXIST;
 473
 474         /* Merge names */
 475         merge_names(u, other);
 476
 477         /* Merge dependencies */
 478         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 479                 merge_dependencies(u, other, d);
 480
 481         other->meta.load_state = UNIT_MERGED;
 482         other->meta.merged_into = u;
 483
 484         /* If there is still some data attached to the other node, we
 485          * don't need it anymore, and can free it. */
 486         if (other->meta.load_state != UNIT_STUB)
 487                 if (UNIT_VTABLE(other)->done)
 488                         UNIT_VTABLE(other)->done(other);
 489
 490         unit_add_to_dbus_queue(u);
 491         unit_add_to_cleanup_queue(other);
 492
 493         return 0;
 494 }
 495
 496 int unit_merge_by_name(Unit *u, const char *name) {
 497         Unit *other;
 498         int r;
 499         char *s = NULL;
 500
 501         assert(u);
 502         assert(name);
 503
 504         if (unit_name_is_template(name)) {
 505                 if (!u->meta.instance)
 506                         return -EINVAL;
 507
 508                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 509                         return -ENOMEM;
 510
 511                 name = s;
 512         }
 513
 514         if (!(other = manager_get_unit(u->meta.manager, name)))
 515                 r = unit_add_name(u, name);
 516         else
 517                 r = unit_merge(u, other);
 518
 519         free(s);
 520         return r;
 521 }
 522
 523 Unit* unit_follow_merge(Unit *u) {
 524         assert(u);
 525
 526         while (u->meta.load_state == UNIT_MERGED)
 527                 assert_se(u = u->meta.merged_into);
 528
 529         return u;
 530 }
 531
 532 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 533         int r;
 534
 535         assert(u);
 536         assert(c);
 537
 538         if (c->std_output != EXEC_OUTPUT_KMSG &&
 539             c->std_output != EXEC_OUTPUT_SYSLOG &&
 540             c->std_error != EXEC_OUTPUT_KMSG &&
 541             c->std_error != EXEC_OUTPUT_SYSLOG)
 542                 return 0;
 543
 544         /* If syslog or kernel logging is requested, make sure our own
 545          * logging daemon is run first. */
 546
 547         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 548                 return r;
 549
 550         if (u->meta.manager->running_as == MANAGER_SYSTEM)
 551                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 552                         return r;
 553
 554         return 0;
 555 }
 556
 557 const char *unit_description(Unit *u) {
 558         assert(u);
 559
 560         if (u->meta.description)
 561                 return u->meta.description;
 562
 563         return u->meta.id;
 564 }
 565
 566 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 567         char *t;
 568         UnitDependency d;
 569         Iterator i;
 570         char *p2;
 571         const char *prefix2;
 572         CGroupBonding *b;
 573         char
 574                 timestamp1[FORMAT_TIMESTAMP_MAX],
 575                 timestamp2[FORMAT_TIMESTAMP_MAX],
 576                 timestamp3[FORMAT_TIMESTAMP_MAX],
 577                 timestamp4[FORMAT_TIMESTAMP_MAX];
 578
 579         assert(u);
 580         assert(u->meta.type >= 0);
 581
 582         if (!prefix)
 583                 prefix = "";
 584         p2 = strappend(prefix, "\t");
 585         prefix2 = p2 ? p2 : prefix;
 586
 587         fprintf(f,
 588                 "%s-> Unit %s:\n"
 589                 "%s\tDescription: %s\n"
 590                 "%s\tInstance: %s\n"
 591                 "%s\tUnit Load State: %s\n"
 592                 "%s\tUnit Active State: %s\n"
 593                 "%s\tInactive Exit Timestamp: %s\n"
 594                 "%s\tActive Enter Timestamp: %s\n"
 595                 "%s\tActive Exit Timestamp: %s\n"
 596                 "%s\tInactive Enter Timestamp: %s\n"
 597                 "%s\tGC Check Good: %s\n",
 598                 prefix, u->meta.id,
 599                 prefix, unit_description(u),
 600                 prefix, strna(u->meta.instance),
 601                 prefix, unit_load_state_to_string(u->meta.load_state),
 602                 prefix, unit_active_state_to_string(unit_active_state(u)),
 603                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 604                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 605                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 606                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 607                 prefix, yes_no(unit_check_gc(u)));
 608
 609         SET_FOREACH(t, u->meta.names, i)
 610                 fprintf(f, "%s\tName: %s\n", prefix, t);
 611
 612         if (u->meta.fragment_path)
 613                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 614
 615         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 616                 Unit *other;
 617
 618                 SET_FOREACH(other, u->meta.dependencies[d], i)
 619                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 620         }
 621
 622         if (u->meta.load_state == UNIT_LOADED) {
 623                 fprintf(f,
 624                         "%s\tRecursive Stop: %s\n"
 625                         "%s\tStopWhenUnneeded: %s\n"
 626                         "%s\tOnlyByDependency: %s\n"
 627                         "%s\tDefaultDependencies: %s\n",
 628                         prefix, yes_no(u->meta.recursive_stop),
 629                         prefix, yes_no(u->meta.stop_when_unneeded),
 630                         prefix, yes_no(u->meta.only_by_dependency),
 631                         prefix, yes_no(u->meta.default_dependencies));
 632
 633                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 634                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 635                                 prefix, b->controller, b->path);
 636
 637                 if (UNIT_VTABLE(u)->dump)
 638                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 639
 640         } else if (u->meta.load_state == UNIT_MERGED)
 641                 fprintf(f,
 642                         "%s\tMerged into: %s\n",
 643                         prefix, u->meta.merged_into->meta.id);
 644
 645         if (u->meta.job)
 646                 job_dump(u->meta.job, f, prefix2);
 647
 648         free(p2);
 649 }
 650
 651 /* Common implementation for multiple backends */
 652 int unit_load_fragment_and_dropin(Unit *u) {
 653         int r;
 654
 655         assert(u);
 656
 657         /* Load a .service file */
 658         if ((r = unit_load_fragment(u)) < 0)
 659                 return r;
 660
 661         if (u->meta.load_state == UNIT_STUB)
 662                 return -ENOENT;
 663
 664         /* Load drop-in directory data */
 665         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 666                 return r;
 667
 668         return 0;
 669 }
 670
 671 /* Common implementation for multiple backends */
 672 int unit_load_fragment_and_dropin_optional(Unit *u) {
 673         int r;
 674
 675         assert(u);
 676
 677         /* Same as unit_load_fragment_and_dropin(), but whether
 678          * something can be loaded or not doesn't matter. */
 679
 680         /* Load a .service file */
 681         if ((r = unit_load_fragment(u)) < 0)
 682                 return r;
 683
 684         if (u->meta.load_state == UNIT_STUB)
 685                 u->meta.load_state = UNIT_LOADED;
 686
 687         /* Load drop-in directory data */
 688         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 689                 return r;
 690
 691         return 0;
 692 }
 693
 694 /* Common implementation for multiple backends */
 695 int unit_load_nop(Unit *u) {
 696         assert(u);
 697
 698         if (u->meta.load_state == UNIT_STUB)
 699                 u->meta.load_state = UNIT_LOADED;
 700
 701         return 0;
 702 }
 703
 704 int unit_load(Unit *u) {
 705         int r;
 706
 707         assert(u);
 708
 709         if (u->meta.in_load_queue) {
 710                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 711                 u->meta.in_load_queue = false;
 712         }
 713
 714         if (u->meta.type == _UNIT_TYPE_INVALID)
 715                 return -EINVAL;
 716
 717         if (u->meta.load_state != UNIT_STUB)
 718                 return 0;
 719
 720         if (UNIT_VTABLE(u)->load)
 721                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 722                         goto fail;
 723
 724         if (u->meta.load_state == UNIT_STUB) {
 725                 r = -ENOENT;
 726                 goto fail;
 727         }
 728
 729         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 730
 731         unit_add_to_dbus_queue(unit_follow_merge(u));
 732         unit_add_to_gc_queue(u);
 733
 734         return 0;
 735
 736 fail:
 737         u->meta.load_state = UNIT_FAILED;
 738         unit_add_to_dbus_queue(u);
 739
 740         log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 741
 742         return r;
 743 }
 744
 745 /* Errors:
 746  *         -EBADR:     This unit type does not support starting.
 747  *         -EALREADY:  Unit is already started.
 748  *         -EAGAIN:    An operation is already in progress. Retry later.
 749  *         -ECANCELED: Too many requests for now.
 750  */
 751 int unit_start(Unit *u) {
 752         UnitActiveState state;
 753
 754         assert(u);
 755
 756         if (u->meta.load_state != UNIT_LOADED)
 757                 return -EINVAL;
 758
 759         /* If this is already (being) started, then this will
 760          * succeed. Note that this will even succeed if this unit is
 761          * not startable by the user. This is relied on to detect when
 762          * we need to wait for units and when waiting is finished. */
 763         state = unit_active_state(u);
 764         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 765                 return -EALREADY;
 766
 767         /* If it is stopped, but we cannot start it, then fail */
 768         if (!UNIT_VTABLE(u)->start)
 769                 return -EBADR;
 770
 771         /* We don't suppress calls to ->start() here when we are
 772          * already starting, to allow this request to be used as a
 773          * "hurry up" call, for example when the unit is in some "auto
 774          * restart" state where it waits for a holdoff timer to elapse
 775          * before it will start again. */
 776
 777         unit_add_to_dbus_queue(u);
 778         return UNIT_VTABLE(u)->start(u);
 779 }
 780
 781 bool unit_can_start(Unit *u) {
 782         assert(u);
 783
 784         return !!UNIT_VTABLE(u)->start;
 785 }
 786
 787 /* Errors:
 788  *         -EBADR:    This unit type does not support stopping.
 789  *         -EALREADY: Unit is already stopped.
 790  *         -EAGAIN:   An operation is already in progress. Retry later.
 791  */
 792 int unit_stop(Unit *u) {
 793         UnitActiveState state;
 794
 795         assert(u);
 796
 797         state = unit_active_state(u);
 798         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(state))
 799                 return -EALREADY;
 800
 801         if (!UNIT_VTABLE(u)->stop)
 802                 return -EBADR;
 803
 804         unit_add_to_dbus_queue(u);
 805         return UNIT_VTABLE(u)->stop(u);
 806 }
 807
 808 /* Errors:
 809  *         -EBADR:    This unit type does not support reloading.
 810  *         -ENOEXEC:  Unit is not started.
 811  *         -EAGAIN:   An operation is already in progress. Retry later.
 812  */
 813 int unit_reload(Unit *u) {
 814         UnitActiveState state;
 815
 816         assert(u);
 817
 818         if (u->meta.load_state != UNIT_LOADED)
 819                 return -EINVAL;
 820
 821         if (!unit_can_reload(u))
 822                 return -EBADR;
 823
 824         state = unit_active_state(u);
 825         if (unit_active_state(u) == UNIT_RELOADING)
 826                 return -EALREADY;
 827
 828         if (unit_active_state(u) != UNIT_ACTIVE)
 829                 return -ENOEXEC;
 830
 831         unit_add_to_dbus_queue(u);
 832         return UNIT_VTABLE(u)->reload(u);
 833 }
 834
 835 bool unit_can_reload(Unit *u) {
 836         assert(u);
 837
 838         if (!UNIT_VTABLE(u)->reload)
 839                 return false;
 840
 841         if (!UNIT_VTABLE(u)->can_reload)
 842                 return true;
 843
 844         return UNIT_VTABLE(u)->can_reload(u);
 845 }
 846
 847 static void unit_check_uneeded(Unit *u) {
 848         Iterator i;
 849         Unit *other;
 850
 851         assert(u);
 852
 853         /* If this service shall be shut down when unneeded then do
 854          * so. */
 855
 856         if (!u->meta.stop_when_unneeded)
 857                 return;
 858
 859         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 860                 return;
 861
 862         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 863                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 864                         return;
 865
 866         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 867                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 868                         return;
 869
 870         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 871                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 872                         return;
 873
 874         log_debug("Service %s is not needed anymore. Stopping.", u->meta.id);
 875
 876         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 877         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL);
 878 }
 879
 880 static void retroactively_start_dependencies(Unit *u) {
 881         Iterator i;
 882         Unit *other;
 883
 884         assert(u);
 885         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
 886
 887         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 888                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 889                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 890
 891         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 892                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 893                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 894
 895         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 896                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 897                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 898
 899         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 900                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 901                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 902
 903         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
 904                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 905                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 906 }
 907
 908 static void retroactively_stop_dependencies(Unit *u) {
 909         Iterator i;
 910         Unit *other;
 911
 912         assert(u);
 913         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
 914
 915         if (u->meta.recursive_stop) {
 916                 /* Pull down units need us recursively if enabled */
 917                 SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 918                         if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 919                                 manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 920         }
 921
 922         /* Garbage collect services that might not be needed anymore, if enabled */
 923         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 924                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 925                         unit_check_uneeded(other);
 926         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 927                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 928                         unit_check_uneeded(other);
 929         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 930                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 931                         unit_check_uneeded(other);
 932         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 933                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 934                         unit_check_uneeded(other);
 935         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
 936                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 937                         unit_check_uneeded(other);
 938 }
 939
 940 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
 941         bool unexpected = false;
 942         dual_timestamp ts;
 943
 944         assert(u);
 945         assert(os < _UNIT_ACTIVE_STATE_MAX);
 946         assert(ns < _UNIT_ACTIVE_STATE_MAX);
 947
 948         /* Note that this is called for all low-level state changes,
 949          * even if they might map to the same high-level
 950          * UnitActiveState! That means that ns == os is OK an expected
 951          * behaviour here. For example: if a mount point is remounted
 952          * this function will be called too and the utmp code below
 953          * relies on that! */
 954
 955         dual_timestamp_get(&ts);
 956
 957         if (UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && !UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 958                 u->meta.inactive_exit_timestamp = ts;
 959         else if (!UNIT_IS_INACTIVE_OR_MAINTENANCE(os) && UNIT_IS_INACTIVE_OR_MAINTENANCE(ns))
 960                 u->meta.inactive_enter_timestamp = ts;
 961
 962         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
 963                 u->meta.active_enter_timestamp = ts;
 964         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
 965                 u->meta.active_exit_timestamp = ts;
 966
 967         timer_unit_notify(u, ns);
 968         path_unit_notify(u, ns);
 969
 970         if (u->meta.job) {
 971
 972                 if (u->meta.job->state == JOB_WAITING)
 973
 974                         /* So we reached a different state for this
 975                          * job. Let's see if we can run it now if it
 976                          * failed previously due to EAGAIN. */
 977                         job_add_to_run_queue(u->meta.job);
 978
 979
 980                 /* Let's check whether this state change constitutes a
 981                  * finished job, or maybe cotradicts a running job and
 982                  * hence needs to invalidate jobs. */
 983
 984                 switch (u->meta.job->type) {
 985
 986                 case JOB_START:
 987                 case JOB_VERIFY_ACTIVE:
 988
 989                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
 990                                 job_finish_and_invalidate(u->meta.job, true);
 991                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
 992                                 unexpected = true;
 993                                 job_finish_and_invalidate(u->meta.job, false);
 994                         }
 995
 996                         break;
 997
 998                 case JOB_RELOAD:
 999                 case JOB_RELOAD_OR_START:
1000
1001                         if (u->meta.job->state == JOB_RUNNING) {
1002                                 if (ns == UNIT_ACTIVE)
1003                                         job_finish_and_invalidate(u->meta.job, true);
1004                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
1005                                         unexpected = true;
1006                                         job_finish_and_invalidate(u->meta.job, false);
1007                                 }
1008                         }
1009
1010                         break;
1011
1012                 case JOB_STOP:
1013                 case JOB_RESTART:
1014                 case JOB_TRY_RESTART:
1015
1016                         if (ns == UNIT_INACTIVE)
1017                                 job_finish_and_invalidate(u->meta.job, true);
1018                         else if (ns == UNIT_MAINTENANCE)
1019                                 job_finish_and_invalidate(u->meta.job, false);
1020                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_DEACTIVATING) {
1021                                 unexpected = true;
1022                                 job_finish_and_invalidate(u->meta.job, false);
1023                         }
1024
1025                         break;
1026
1027                 default:
1028                         assert_not_reached("Job type unknown");
1029                 }
1030         }
1031
1032         /* If this state change happened without being requested by a
1033          * job, then let's retroactively start or stop dependencies */
1034
1035         if (unexpected) {
1036                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1037                         retroactively_start_dependencies(u);
1038                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1039                         retroactively_stop_dependencies(u);
1040         }
1041
1042         /* Some names are special */
1043         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1044                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1045                         /* The bus just might have become available,
1046                          * hence try to connect to it, if we aren't
1047                          * yet connected. */
1048                         bus_init(u->meta.manager);
1049                 }
1050
1051                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1052                         /* The syslog daemon just might have become
1053                          * available, hence try to connect to it, if
1054                          * we aren't yet connected. */
1055                         log_open();
1056
1057                 if (u->meta.type == UNIT_MOUNT)
1058                         /* Another directory became available, let's
1059                          * check if that is enough to write our utmp
1060                          * entry. */
1061                         manager_write_utmp_reboot(u->meta.manager);
1062
1063                 if (u->meta.type == UNIT_TARGET)
1064                         /* A target got activated, maybe this is a runlevel? */
1065                         manager_write_utmp_runlevel(u->meta.manager, u);
1066
1067         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1068
1069                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1070                         /* The syslog daemon might just have
1071                          * terminated, hence try to disconnect from
1072                          * it. */
1073                         log_close_syslog();
1074
1075                 /* We don't care about D-Bus here, since we'll get an
1076                  * asynchronous notification for it anyway. */
1077         }
1078
1079         /* Maybe we finished startup and are now ready for being
1080          * stopped because unneeded? */
1081         unit_check_uneeded(u);
1082
1083         unit_add_to_dbus_queue(u);
1084         unit_add_to_gc_queue(u);
1085 }
1086
1087 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1088         struct epoll_event ev;
1089
1090         assert(u);
1091         assert(fd >= 0);
1092         assert(w);
1093         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1094
1095         zero(ev);
1096         ev.data.ptr = w;
1097         ev.events = events;
1098
1099         if (epoll_ctl(u->meta.manager->epoll_fd,
1100                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1101                       fd,
1102                       &ev) < 0)
1103                 return -errno;
1104
1105         w->fd = fd;
1106         w->type = WATCH_FD;
1107         w->data.unit = u;
1108
1109         return 0;
1110 }
1111
1112 void unit_unwatch_fd(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_FD);
1120         assert(w->data.unit == u);
1121         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1122
1123         w->fd = -1;
1124         w->type = WATCH_INVALID;
1125         w->data.unit = NULL;
1126 }
1127
1128 int unit_watch_pid(Unit *u, pid_t pid) {
1129         assert(u);
1130         assert(pid >= 1);
1131
1132         /* Watch a specific PID. We only support one unit watching
1133          * each PID for now. */
1134
1135         return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1136 }
1137
1138 void unit_unwatch_pid(Unit *u, pid_t pid) {
1139         assert(u);
1140         assert(pid >= 1);
1141
1142         hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1143 }
1144
1145 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1146         struct itimerspec its;
1147         int flags, fd;
1148         bool ours;
1149
1150         assert(u);
1151         assert(w);
1152         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1153
1154         /* This will try to reuse the old timer if there is one */
1155
1156         if (w->type == WATCH_TIMER) {
1157                 ours = false;
1158                 fd = w->fd;
1159         } else {
1160                 ours = true;
1161                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1162                         return -errno;
1163         }
1164
1165         zero(its);
1166
1167         if (delay <= 0) {
1168                 /* Set absolute time in the past, but not 0, since we
1169                  * don't want to disarm the timer */
1170                 its.it_value.tv_sec = 0;
1171                 its.it_value.tv_nsec = 1;
1172
1173                 flags = TFD_TIMER_ABSTIME;
1174         } else {
1175                 timespec_store(&its.it_value, delay);
1176                 flags = 0;
1177         }
1178
1179         /* This will also flush the elapse counter */
1180         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1181                 goto fail;
1182
1183         if (w->type == WATCH_INVALID) {
1184                 struct epoll_event ev;
1185
1186                 zero(ev);
1187                 ev.data.ptr = w;
1188                 ev.events = EPOLLIN;
1189
1190                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1191                         goto fail;
1192         }
1193
1194         w->fd = fd;
1195         w->type = WATCH_TIMER;
1196         w->data.unit = u;
1197
1198         return 0;
1199
1200 fail:
1201         if (ours)
1202                 close_nointr_nofail(fd);
1203
1204         return -errno;
1205 }
1206
1207 void unit_unwatch_timer(Unit *u, Watch *w) {
1208         assert(u);
1209         assert(w);
1210
1211         if (w->type == WATCH_INVALID)
1212                 return;
1213
1214         assert(w->type == WATCH_TIMER && w->data.unit == u);
1215
1216         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1217         close_nointr_nofail(w->fd);
1218
1219         w->fd = -1;
1220         w->type = WATCH_INVALID;
1221         w->data.unit = NULL;
1222 }
1223
1224 bool unit_job_is_applicable(Unit *u, JobType j) {
1225         assert(u);
1226         assert(j >= 0 && j < _JOB_TYPE_MAX);
1227
1228         switch (j) {
1229
1230         case JOB_VERIFY_ACTIVE:
1231         case JOB_START:
1232                 return true;
1233
1234         case JOB_STOP:
1235         case JOB_RESTART:
1236         case JOB_TRY_RESTART:
1237                 return unit_can_start(u);
1238
1239         case JOB_RELOAD:
1240                 return unit_can_reload(u);
1241
1242         case JOB_RELOAD_OR_START:
1243                 return unit_can_reload(u) && unit_can_start(u);
1244
1245         default:
1246                 assert_not_reached("Invalid job type");
1247         }
1248 }
1249
1250 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1251
1252         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1253                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1254                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1255                 [UNIT_WANTS] = UNIT_WANTED_BY,
1256                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1257                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1258                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1259                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1260                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1261                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1262                 [UNIT_BEFORE] = UNIT_AFTER,
1263                 [UNIT_AFTER] = UNIT_BEFORE,
1264                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1265                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1266         };
1267         int r, q = 0, v = 0, w = 0;
1268
1269         assert(u);
1270         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1271         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1272         assert(other);
1273
1274         /* We won't allow dependencies on ourselves. We will not
1275          * consider them an error however. */
1276         if (u == other)
1277                 return 0;
1278
1279         if (UNIT_VTABLE(u)->no_requires &&
1280             (d == UNIT_REQUIRES ||
1281              d == UNIT_REQUIRES_OVERRIDABLE ||
1282              d == UNIT_REQUISITE ||
1283              d == UNIT_REQUISITE_OVERRIDABLE)) {
1284                     return -EINVAL;
1285         }
1286
1287         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1288             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1289                 return r;
1290
1291         if (add_reference)
1292                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1293                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1294                         return r;
1295
1296         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1297                 return q;
1298
1299         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1300                 r = v;
1301                 goto fail;
1302         }
1303
1304         if (add_reference) {
1305                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1306                         r = w;
1307                         goto fail;
1308                 }
1309
1310                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1311                         goto fail;
1312         }
1313
1314         unit_add_to_dbus_queue(u);
1315         return 0;
1316
1317 fail:
1318         if (q > 0)
1319                 set_remove(u->meta.dependencies[d], other);
1320
1321         if (v > 0)
1322                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1323
1324         if (w > 0)
1325                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1326
1327         return r;
1328 }
1329
1330 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference) {
1331         int r;
1332
1333         assert(u);
1334
1335         if ((r = unit_add_dependency(u, d, other, add_reference)) < 0)
1336                 return r;
1337
1338         if ((r = unit_add_dependency(u, e, other, add_reference)) < 0)
1339                 return r;
1340
1341         return 0;
1342 }
1343
1344 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1345         char *s;
1346
1347         assert(u);
1348         assert(name || path);
1349
1350         if (!name)
1351                 name = file_name_from_path(path);
1352
1353         if (!unit_name_is_template(name)) {
1354                 *p = NULL;
1355                 return name;
1356         }
1357
1358         if (u->meta.instance)
1359                 s = unit_name_replace_instance(name, u->meta.instance);
1360         else {
1361                 char *i;
1362
1363                 if (!(i = unit_name_to_prefix(u->meta.id)))
1364                         return NULL;
1365
1366                 s = unit_name_replace_instance(name, i);
1367                 free(i);
1368         }
1369
1370         if (!s)
1371                 return NULL;
1372
1373         *p = s;
1374         return s;
1375 }
1376
1377 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1378         Unit *other;
1379         int r;
1380         char *s;
1381
1382         assert(u);
1383         assert(name || path);
1384
1385         if (!(name = resolve_template(u, name, path, &s)))
1386                 return -ENOMEM;
1387
1388         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1389                 goto finish;
1390
1391         r = unit_add_dependency(u, d, other, add_reference);
1392
1393 finish:
1394         free(s);
1395         return r;
1396 }
1397
1398 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1399         Unit *other;
1400         int r;
1401         char *s;
1402
1403         assert(u);
1404         assert(name || path);
1405
1406         if (!(name = resolve_template(u, name, path, &s)))
1407                 return -ENOMEM;
1408
1409         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1410                 goto finish;
1411
1412         r = unit_add_two_dependencies(u, d, e, other, add_reference);
1413
1414 finish:
1415         free(s);
1416         return r;
1417 }
1418
1419 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1420         Unit *other;
1421         int r;
1422         char *s;
1423
1424         assert(u);
1425         assert(name || path);
1426
1427         if (!(name = resolve_template(u, name, path, &s)))
1428                 return -ENOMEM;
1429
1430         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1431                 goto finish;
1432
1433         r = unit_add_dependency(other, d, u, add_reference);
1434
1435 finish:
1436         free(s);
1437         return r;
1438 }
1439
1440 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
1441         Unit *other;
1442         int r;
1443         char *s;
1444
1445         assert(u);
1446         assert(name || path);
1447
1448         if (!(name = resolve_template(u, name, path, &s)))
1449                 return -ENOMEM;
1450
1451         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1452                 goto finish;
1453
1454         if ((r = unit_add_two_dependencies(other, d, e, u, add_reference)) < 0)
1455                 goto finish;
1456
1457 finish:
1458         free(s);
1459         return r;
1460 }
1461
1462 int set_unit_path(const char *p) {
1463         char *cwd, *c;
1464         int r;
1465
1466         /* This is mostly for debug purposes */
1467
1468         if (path_is_absolute(p)) {
1469                 if (!(c = strdup(p)))
1470                         return -ENOMEM;
1471         } else {
1472                 if (!(cwd = get_current_dir_name()))
1473                         return -errno;
1474
1475                 r = asprintf(&c, "%s/%s", cwd, p);
1476                 free(cwd);
1477
1478                 if (r < 0)
1479                         return -ENOMEM;
1480         }
1481
1482         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1483                 r = -errno;
1484                 free(c);
1485                 return r;
1486         }
1487
1488         return 0;
1489 }
1490
1491 char *unit_dbus_path(Unit *u) {
1492         char *p, *e;
1493
1494         assert(u);
1495
1496         if (!(e = bus_path_escape(u->meta.id)))
1497                 return NULL;
1498
1499         if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
1500                 free(e);
1501                 return NULL;
1502         }
1503
1504         free(e);
1505         return p;
1506 }
1507
1508 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1509         CGroupBonding *l;
1510         int r;
1511
1512         assert(u);
1513         assert(b);
1514         assert(b->path);
1515
1516         /* Ensure this hasn't been added yet */
1517         assert(!b->unit);
1518
1519         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1520         LIST_PREPEND(CGroupBonding, by_path, l, b);
1521
1522         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1523                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1524                 return r;
1525         }
1526
1527         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1528         b->unit = u;
1529
1530         return 0;
1531 }
1532
1533 static char *default_cgroup_path(Unit *u) {
1534         char *p;
1535         int r;
1536
1537         assert(u);
1538
1539         if (u->meta.instance) {
1540                 char *t;
1541
1542                 if (!(t = unit_name_template(u->meta.id)))
1543                         return NULL;
1544
1545                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1546                 free(t);
1547         } else
1548                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1549
1550         return r < 0 ? NULL : p;
1551 }
1552
1553 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1554         size_t n;
1555         char *controller = NULL, *path = NULL;
1556         CGroupBonding *b = NULL;
1557         int r;
1558
1559         assert(u);
1560         assert(name);
1561
1562         /* Detect controller name */
1563         n = strcspn(name, ":");
1564
1565         if (name[n] == 0 ||
1566             (name[n] == ':' && name[n+1] == 0)) {
1567
1568                 /* Only controller name, no path? */
1569
1570                 if (!(path = default_cgroup_path(u)))
1571                         return -ENOMEM;
1572
1573         } else {
1574                 const char *p;
1575
1576                 /* Controller name, and path. */
1577                 p = name+n+1;
1578
1579                 if (!path_is_absolute(p))
1580                         return -EINVAL;
1581
1582                 if (!(path = strdup(p)))
1583                         return -ENOMEM;
1584         }
1585
1586         if (n > 0)
1587                 controller = strndup(name, n);
1588         else
1589                 controller = strdup(u->meta.manager->cgroup_controller);
1590
1591         if (!controller) {
1592                 r = -ENOMEM;
1593                 goto fail;
1594         }
1595
1596         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1597                 r = -EEXIST;
1598                 goto fail;
1599         }
1600
1601         if (!(b = new0(CGroupBonding, 1))) {
1602                 r = -ENOMEM;
1603                 goto fail;
1604         }
1605
1606         b->controller = controller;
1607         b->path = path;
1608         b->only_us = false;
1609         b->clean_up = false;
1610
1611         if ((r = unit_add_cgroup(u, b)) < 0)
1612                 goto fail;
1613
1614         return 0;
1615
1616 fail:
1617         free(path);
1618         free(controller);
1619         free(b);
1620
1621         return r;
1622 }
1623
1624 int unit_add_default_cgroup(Unit *u) {
1625         CGroupBonding *b;
1626         int r = -ENOMEM;
1627
1628         assert(u);
1629
1630         /* Adds in the default cgroup data, if it wasn't specified yet */
1631
1632         if (unit_get_default_cgroup(u))
1633                 return 0;
1634
1635         if (!(b = new0(CGroupBonding, 1)))
1636                 return -ENOMEM;
1637
1638         if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
1639                 goto fail;
1640
1641         if (!(b->path = default_cgroup_path(u)))
1642                 goto fail;
1643
1644         b->clean_up = true;
1645         b->only_us = true;
1646
1647         if ((r = unit_add_cgroup(u, b)) < 0)
1648                 goto fail;
1649
1650         return 0;
1651
1652 fail:
1653         free(b->path);
1654         free(b->controller);
1655         free(b);
1656
1657         return r;
1658 }
1659
1660 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1661         assert(u);
1662
1663         return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
1664 }
1665
1666 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1667         char *t;
1668         int r;
1669
1670         assert(u);
1671         assert(type);
1672         assert(_found);
1673
1674         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1675                 return -ENOMEM;
1676
1677         assert(!unit_has_name(u, t));
1678
1679         r = manager_load_unit(u->meta.manager, t, NULL, _found);
1680         free(t);
1681
1682         assert(r < 0 || *_found != u);
1683
1684         return r;
1685 }
1686
1687 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1688         Unit *found;
1689         char *t;
1690
1691         assert(u);
1692         assert(type);
1693         assert(_found);
1694
1695         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1696                 return -ENOMEM;
1697
1698         assert(!unit_has_name(u, t));
1699
1700         found = manager_get_unit(u->meta.manager, t);
1701         free(t);
1702
1703         if (!found)
1704                 return -ENOENT;
1705
1706         *_found = found;
1707         return 0;
1708 }
1709
1710 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1711         Unit *u = userdata;
1712         assert(u);
1713
1714         return unit_name_to_prefix_and_instance(u->meta.id);
1715 }
1716
1717 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1718         Unit *u = userdata;
1719         assert(u);
1720
1721         return unit_name_to_prefix(u->meta.id);
1722 }
1723
1724 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1725         Unit *u = userdata;
1726         char *p, *r;
1727
1728         assert(u);
1729
1730         if (!(p = unit_name_to_prefix(u->meta.id)))
1731                 return NULL;
1732
1733         r = unit_name_unescape(p);
1734         free(p);
1735
1736         return r;
1737 }
1738
1739 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1740         Unit *u = userdata;
1741         assert(u);
1742
1743         if (u->meta.instance)
1744                 return unit_name_unescape(u->meta.instance);
1745
1746         return strdup("");
1747 }
1748
1749 char *unit_name_printf(Unit *u, const char* format) {
1750
1751         /*
1752          * This will use the passed string as format string and
1753          * replace the following specifiers:
1754          *
1755          * %n: the full id of the unit                 (foo@bar.waldo)
1756          * %N: the id of the unit without the suffix   (foo@bar)
1757          * %p: the prefix                              (foo)
1758          * %i: the instance                            (bar)
1759          */
1760
1761         const Specifier table[] = {
1762                 { 'n', specifier_string,              u->meta.id },
1763                 { 'N', specifier_prefix_and_instance, NULL },
1764                 { 'p', specifier_prefix,              NULL },
1765                 { 'i', specifier_string,              u->meta.instance },
1766                 { 0, NULL, NULL }
1767         };
1768
1769         assert(u);
1770         assert(format);
1771
1772         return specifier_printf(format, table, u);
1773 }
1774
1775 char *unit_full_printf(Unit *u, const char *format) {
1776
1777         /* This is similar to unit_name_printf() but also supports
1778          * unescaping */
1779
1780         const Specifier table[] = {
1781                 { 'n', specifier_string,              u->meta.id },
1782                 { 'N', specifier_prefix_and_instance, NULL },
1783                 { 'p', specifier_prefix,              NULL },
1784                 { 'P', specifier_prefix_unescaped,    NULL },
1785                 { 'i', specifier_string,              u->meta.instance },
1786                 { 'I', specifier_instance_unescaped,  NULL },
1787                 { 0, NULL, NULL }
1788         };
1789
1790         assert(u);
1791         assert(format);
1792
1793         return specifier_printf(format, table, u);
1794 }
1795
1796 char **unit_full_printf_strv(Unit *u, char **l) {
1797         size_t n;
1798         char **r, **i, **j;
1799
1800         /* Applies unit_full_printf to every entry in l */
1801
1802         assert(u);
1803
1804         n = strv_length(l);
1805         if (!(r = new(char*, n+1)))
1806                 return NULL;
1807
1808         for (i = l, j = r; *i; i++, j++)
1809                 if (!(*j = unit_full_printf(u, *i)))
1810                         goto fail;
1811
1812         *j = NULL;
1813         return r;
1814
1815 fail:
1816         j--;
1817         while (j >= r)
1818                 free(*j);
1819
1820         free(r);
1821
1822         return NULL;
1823 }
1824
1825 int unit_watch_bus_name(Unit *u, const char *name) {
1826         assert(u);
1827         assert(name);
1828
1829         /* Watch a specific name on the bus. We only support one unit
1830          * watching each name for now. */
1831
1832         return hashmap_put(u->meta.manager->watch_bus, name, u);
1833 }
1834
1835 void unit_unwatch_bus_name(Unit *u, const char *name) {
1836         assert(u);
1837         assert(name);
1838
1839         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1840 }
1841
1842 bool unit_can_serialize(Unit *u) {
1843         assert(u);
1844
1845         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1846 }
1847
1848 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1849         int r;
1850
1851         assert(u);
1852         assert(f);
1853         assert(fds);
1854
1855         if (!unit_can_serialize(u))
1856                 return 0;
1857
1858         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1859                 return r;
1860
1861         if (u->meta.job)
1862                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1863
1864         /* End marker */
1865         fputc('\n', f);
1866         return 0;
1867 }
1868
1869 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1870         va_list ap;
1871
1872         assert(u);
1873         assert(f);
1874         assert(key);
1875         assert(format);
1876
1877         fputs(key, f);
1878         fputc('=', f);
1879
1880         va_start(ap, format);
1881         vfprintf(f, format, ap);
1882         va_end(ap);
1883
1884         fputc('\n', f);
1885 }
1886
1887 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1888         assert(u);
1889         assert(f);
1890         assert(key);
1891         assert(value);
1892
1893         fprintf(f, "%s=%s\n", key, value);
1894 }
1895
1896 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1897         int r;
1898
1899         assert(u);
1900         assert(f);
1901         assert(fds);
1902
1903         if (!unit_can_serialize(u))
1904                 return 0;
1905
1906         for (;;) {
1907                 char line[1024], *l, *v;
1908                 size_t k;
1909
1910                 if (!fgets(line, sizeof(line), f)) {
1911                         if (feof(f))
1912                                 return 0;
1913                         return -errno;
1914                 }
1915
1916                 l = strstrip(line);
1917
1918                 /* End marker */
1919                 if (l[0] == 0)
1920                         return 0;
1921
1922                 k = strcspn(l, "=");
1923
1924                 if (l[k] == '=') {
1925                         l[k] = 0;
1926                         v = l+k+1;
1927                 } else
1928                         v = l+k;
1929
1930                 if (streq(l, "job")) {
1931                         JobType type;
1932
1933                         if ((type = job_type_from_string(v)) < 0)
1934                                 log_debug("Failed to parse job type value %s", v);
1935                         else
1936                                 u->meta.deserialized_job = type;
1937
1938                         continue;
1939                 }
1940
1941                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1942                         return r;
1943         }
1944 }
1945
1946 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1947         Unit *device;
1948         char *e;
1949         int r;
1950
1951         assert(u);
1952
1953         if (!what)
1954                 return 0;
1955
1956         /* Adds in links to the device node that this unit is based on */
1957
1958         if (!is_device_path(what))
1959                 return 0;
1960
1961         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1962                 return -ENOMEM;
1963
1964         r = manager_load_unit(u->meta.manager, e, NULL, &device);
1965         free(e);
1966
1967         if (r < 0)
1968                 return r;
1969
1970         if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_REQUIRES, device, true)) < 0)
1971                 return r;
1972
1973         if (wants)
1974                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1975                         return r;
1976
1977         return 0;
1978 }
1979
1980 int unit_coldplug(Unit *u) {
1981         int r;
1982
1983         assert(u);
1984
1985         if (UNIT_VTABLE(u)->coldplug)
1986                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
1987                         return r;
1988
1989         if (u->meta.deserialized_job >= 0) {
1990                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL)) < 0)
1991                         return r;
1992
1993                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
1994         }
1995
1996         return 0;
1997 }
1998
1999 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
2000         [UNIT_SERVICE] = "service",
2001         [UNIT_TIMER] = "timer",
2002         [UNIT_SOCKET] = "socket",
2003         [UNIT_TARGET] = "target",
2004         [UNIT_DEVICE] = "device",
2005         [UNIT_MOUNT] = "mount",
2006         [UNIT_AUTOMOUNT] = "automount",
2007         [UNIT_SNAPSHOT] = "snapshot",
2008         [UNIT_SWAP] = "swap"
2009 };
2010
2011 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
2012
2013 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
2014         [UNIT_STUB] = "stub",
2015         [UNIT_LOADED] = "loaded",
2016         [UNIT_FAILED] = "failed",
2017         [UNIT_MERGED] = "merged"
2018 };
2019
2020 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
2021
2022 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
2023         [UNIT_ACTIVE] = "active",
2024         [UNIT_RELOADING] = "reloading",
2025         [UNIT_INACTIVE] = "inactive",
2026         [UNIT_MAINTENANCE] = "maintenance",
2027         [UNIT_ACTIVATING] = "activating",
2028         [UNIT_DEACTIVATING] = "deactivating"
2029 };
2030
2031 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
2032
2033 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
2034         [UNIT_REQUIRES] = "Requires",
2035         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
2036         [UNIT_WANTS] = "Wants",
2037         [UNIT_REQUISITE] = "Requisite",
2038         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
2039         [UNIT_REQUIRED_BY] = "RequiredBy",
2040         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
2041         [UNIT_WANTED_BY] = "WantedBy",
2042         [UNIT_CONFLICTS] = "Conflicts",
2043         [UNIT_BEFORE] = "Before",
2044         [UNIT_AFTER] = "After",
2045         [UNIT_REFERENCES] = "References",
2046         [UNIT_REFERENCED_BY] = "ReferencedBy"
2047 };
2048
2049 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
2050
2051 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2052         [KILL_CONTROL_GROUP] = "control-group",
2053         [KILL_PROCESS_GROUP] = "process-group",
2054         [KILL_PROCESS] = "process",
2055         [KILL_NONE] = "none"
2056 };
2057
2058 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);