src/unit.c

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