src/unit.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <sys/epoll.h>
  26 #include <sys/timerfd.h>
  27 #include <sys/poll.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30
  31 #include "set.h"
  32 #include "unit.h"
  33 #include "macro.h"
  34 #include "strv.h"
  35 #include "load-fragment.h"
  36 #include "load-dropin.h"
  37 #include "log.h"
  38 #include "unit-name.h"
  39 #include "specifier.h"
  40 #include "dbus-unit.h"
  41
  42 const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
  43         [UNIT_SERVICE] = &service_vtable,
  44         [UNIT_TIMER] = &timer_vtable,
  45         [UNIT_SOCKET] = &socket_vtable,
  46         [UNIT_TARGET] = &target_vtable,
  47         [UNIT_DEVICE] = &device_vtable,
  48         [UNIT_MOUNT] = &mount_vtable,
  49         [UNIT_AUTOMOUNT] = &automount_vtable,
  50         [UNIT_SNAPSHOT] = &snapshot_vtable,
  51         [UNIT_SWAP] = &swap_vtable,
  52         [UNIT_PATH] = &path_vtable
  53 };
  54
  55 Unit *unit_new(Manager *m) {
  56         Unit *u;
  57
  58         assert(m);
  59
  60         if (!(u = new0(Unit, 1)))
  61                 return NULL;
  62
  63         if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
  64                 free(u);
  65                 return NULL;
  66         }
  67
  68         u->meta.manager = m;
  69         u->meta.type = _UNIT_TYPE_INVALID;
  70         u->meta.deserialized_job = _JOB_TYPE_INVALID;
  71
  72         return u;
  73 }
  74
  75 bool unit_has_name(Unit *u, const char *name) {
  76         assert(u);
  77         assert(name);
  78
  79         return !!set_get(u->meta.names, (char*) name);
  80 }
  81
  82 int unit_add_name(Unit *u, const char *text) {
  83         UnitType t;
  84         char *s = NULL, *i = NULL;
  85         int r;
  86
  87         assert(u);
  88         assert(text);
  89
  90         if (unit_name_is_template(text)) {
  91                 if (!u->meta.instance)
  92                         return -EINVAL;
  93
  94                 s = unit_name_replace_instance(text, u->meta.instance);
  95         } else
  96                 s = strdup(text);
  97
  98         if (!s)
  99                 return -ENOMEM;
 100
 101         if (!unit_name_is_valid(s)) {
 102                 r = -EINVAL;
 103                 goto fail;
 104         }
 105
 106         assert_se((t = unit_name_to_type(s)) >= 0);
 107
 108         if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
 109                 r = -EINVAL;
 110                 goto fail;
 111         }
 112
 113         if ((r = unit_name_to_instance(s, &i)) < 0)
 114                 goto fail;
 115
 116         if (i && unit_vtable[t]->no_instances)
 117                 goto fail;
 118
 119         if (u->meta.type != _UNIT_TYPE_INVALID && !streq_ptr(u->meta.instance, i)) {
 120                 r = -EINVAL;
 121                 goto fail;
 122         }
 123
 124         if (unit_vtable[t]->no_alias &&
 125             !set_isempty(u->meta.names) &&
 126             !set_get(u->meta.names, s)) {
 127                 r = -EEXIST;
 128                 goto fail;
 129         }
 130
 131         if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
 132                 r = -E2BIG;
 133                 goto fail;
 134         }
 135
 136         if ((r = set_put(u->meta.names, s)) < 0) {
 137                 if (r == -EEXIST)
 138                         r = 0;
 139                 goto fail;
 140         }
 141
 142         if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
 143                 set_remove(u->meta.names, s);
 144                 goto fail;
 145         }
 146
 147         if (u->meta.type == _UNIT_TYPE_INVALID) {
 148
 149                 u->meta.type = t;
 150                 u->meta.id = s;
 151                 u->meta.instance = i;
 152
 153                 LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
 154
 155                 if (UNIT_VTABLE(u)->init)
 156                         UNIT_VTABLE(u)->init(u);
 157         } else
 158                 free(i);
 159
 160         unit_add_to_dbus_queue(u);
 161         return 0;
 162
 163 fail:
 164         free(s);
 165         free(i);
 166
 167         return r;
 168 }
 169
 170 int unit_choose_id(Unit *u, const char *name) {
 171         char *s, *t = NULL;
 172
 173         assert(u);
 174         assert(name);
 175
 176         if (unit_name_is_template(name)) {
 177
 178                 if (!u->meta.instance)
 179                         return -EINVAL;
 180
 181                 if (!(t = unit_name_replace_instance(name, u->meta.instance)))
 182                         return -ENOMEM;
 183
 184                 name = t;
 185         }
 186
 187         /* Selects one of the names of this unit as the id */
 188         s = set_get(u->meta.names, (char*) name);
 189         free(t);
 190
 191         if (!s)
 192                 return -ENOENT;
 193
 194         u->meta.id = s;
 195         unit_add_to_dbus_queue(u);
 196
 197         return 0;
 198 }
 199
 200 int unit_set_description(Unit *u, const char *description) {
 201         char *s;
 202
 203         assert(u);
 204
 205         if (!(s = strdup(description)))
 206                 return -ENOMEM;
 207
 208         free(u->meta.description);
 209         u->meta.description = s;
 210
 211         unit_add_to_dbus_queue(u);
 212         return 0;
 213 }
 214
 215 bool unit_check_gc(Unit *u) {
 216         assert(u);
 217
 218         if (u->meta.load_state == UNIT_STUB)
 219                 return true;
 220
 221         if (UNIT_VTABLE(u)->no_gc)
 222                 return true;
 223
 224         if (u->meta.job)
 225                 return true;
 226
 227         if (unit_active_state(u) != UNIT_INACTIVE)
 228                 return true;
 229
 230         if (UNIT_VTABLE(u)->check_gc)
 231                 if (UNIT_VTABLE(u)->check_gc(u))
 232                         return true;
 233
 234         return false;
 235 }
 236
 237 void unit_add_to_load_queue(Unit *u) {
 238         assert(u);
 239         assert(u->meta.type != _UNIT_TYPE_INVALID);
 240
 241         if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
 242                 return;
 243
 244         LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 245         u->meta.in_load_queue = true;
 246 }
 247
 248 void unit_add_to_cleanup_queue(Unit *u) {
 249         assert(u);
 250
 251         if (u->meta.in_cleanup_queue)
 252                 return;
 253
 254         LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 255         u->meta.in_cleanup_queue = true;
 256 }
 257
 258 void unit_add_to_gc_queue(Unit *u) {
 259         assert(u);
 260
 261         if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
 262                 return;
 263
 264         if (unit_check_gc(u))
 265                 return;
 266
 267         LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 268         u->meta.in_gc_queue = true;
 269
 270         u->meta.manager->n_in_gc_queue ++;
 271
 272         if (u->meta.manager->gc_queue_timestamp <= 0)
 273                 u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
 274 }
 275
 276 void unit_add_to_dbus_queue(Unit *u) {
 277         assert(u);
 278         assert(u->meta.type != _UNIT_TYPE_INVALID);
 279
 280         if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
 281                 return;
 282
 283         if (set_isempty(u->meta.manager->subscribed)) {
 284                 u->meta.sent_dbus_new_signal = true;
 285                 return;
 286         }
 287
 288         LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 289         u->meta.in_dbus_queue = true;
 290 }
 291
 292 static void bidi_set_free(Unit *u, Set *s) {
 293         Iterator i;
 294         Unit *other;
 295
 296         assert(u);
 297
 298         /* Frees the set and makes sure we are dropped from the
 299          * inverse pointers */
 300
 301         SET_FOREACH(other, s, i) {
 302                 UnitDependency d;
 303
 304                 for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 305                         set_remove(other->meta.dependencies[d], u);
 306
 307                 unit_add_to_gc_queue(other);
 308         }
 309
 310         set_free(s);
 311 }
 312
 313 void unit_free(Unit *u) {
 314         UnitDependency d;
 315         Iterator i;
 316         char *t;
 317
 318         assert(u);
 319
 320         bus_unit_send_removed_signal(u);
 321
 322         /* Detach from next 'bigger' objects */
 323         SET_FOREACH(t, u->meta.names, i)
 324                 hashmap_remove_value(u->meta.manager->units, t, u);
 325
 326         if (u->meta.type != _UNIT_TYPE_INVALID)
 327                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 328
 329         if (u->meta.in_load_queue)
 330                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 331
 332         if (u->meta.in_dbus_queue)
 333                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 334
 335         if (u->meta.in_cleanup_queue)
 336                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 337
 338         if (u->meta.in_gc_queue) {
 339                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 340                 u->meta.manager->n_in_gc_queue--;
 341         }
 342
 343         /* Free data and next 'smaller' objects */
 344         if (u->meta.job)
 345                 job_free(u->meta.job);
 346
 347         if (u->meta.load_state != UNIT_STUB)
 348                 if (UNIT_VTABLE(u)->done)
 349                         UNIT_VTABLE(u)->done(u);
 350
 351         cgroup_bonding_free_list(u->meta.cgroup_bondings);
 352
 353         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 354                 bidi_set_free(u, u->meta.dependencies[d]);
 355
 356         free(u->meta.description);
 357         free(u->meta.fragment_path);
 358
 359         while ((t = set_steal_first(u->meta.names)))
 360                 free(t);
 361         set_free(u->meta.names);
 362
 363         free(u->meta.instance);
 364
 365         free(u);
 366 }
 367
 368 UnitActiveState unit_active_state(Unit *u) {
 369         assert(u);
 370
 371         if (u->meta.load_state != UNIT_LOADED)
 372                 return UNIT_INACTIVE;
 373
 374         return UNIT_VTABLE(u)->active_state(u);
 375 }
 376
 377 const char* unit_sub_state_to_string(Unit *u) {
 378         assert(u);
 379
 380         return UNIT_VTABLE(u)->sub_state_to_string(u);
 381 }
 382
 383 static void complete_move(Set **s, Set **other) {
 384         assert(s);
 385         assert(other);
 386
 387         if (!*other)
 388                 return;
 389
 390         if (*s)
 391                 set_move(*s, *other);
 392         else {
 393                 *s = *other;
 394                 *other = NULL;
 395         }
 396 }
 397
 398 static void merge_names(Unit *u, Unit *other) {
 399         char *t;
 400         Iterator i;
 401
 402         assert(u);
 403         assert(other);
 404
 405         complete_move(&u->meta.names, &other->meta.names);
 406
 407         while ((t = set_steal_first(other->meta.names)))
 408                 free(t);
 409
 410         set_free(other->meta.names);
 411         other->meta.names = NULL;
 412         other->meta.id = NULL;
 413
 414         SET_FOREACH(t, u->meta.names, i)
 415                 assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
 416 }
 417
 418 static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
 419         Iterator i;
 420         Unit *back;
 421         int r;
 422
 423         assert(u);
 424         assert(other);
 425         assert(d < _UNIT_DEPENDENCY_MAX);
 426
 427         SET_FOREACH(back, other->meta.dependencies[d], i) {
 428                 UnitDependency k;
 429
 430                 for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
 431                         if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
 432
 433                                 if (r == -EEXIST)
 434                                         set_remove(back->meta.dependencies[k], other);
 435                                 else
 436                                         assert(r == -ENOENT);
 437                         }
 438         }
 439
 440         complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
 441
 442         set_free(other->meta.dependencies[d]);
 443         other->meta.dependencies[d] = NULL;
 444 }
 445
 446 int unit_merge(Unit *u, Unit *other) {
 447         UnitDependency d;
 448
 449         assert(u);
 450         assert(other);
 451         assert(u->meta.manager == other->meta.manager);
 452         assert(u->meta.type != _UNIT_TYPE_INVALID);
 453
 454         other = unit_follow_merge(other);
 455
 456         if (other == u)
 457                 return 0;
 458
 459         if (u->meta.type != other->meta.type)
 460                 return -EINVAL;
 461
 462         if (!streq_ptr(u->meta.instance, other->meta.instance))
 463                 return -EINVAL;
 464
 465         if (other->meta.load_state != UNIT_STUB &&
 466             other->meta.load_state != UNIT_FAILED)
 467                 return -EEXIST;
 468
 469         if (other->meta.job)
 470                 return -EEXIST;
 471
 472         if (unit_active_state(other) != UNIT_INACTIVE)
 473                 return -EEXIST;
 474
 475         /* Merge names */
 476         merge_names(u, other);
 477
 478         /* Merge dependencies */
 479         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
 480                 merge_dependencies(u, other, d);
 481
 482         other->meta.load_state = UNIT_MERGED;
 483         other->meta.merged_into = u;
 484
 485         /* If there is still some data attached to the other node, we
 486          * don't need it anymore, and can free it. */
 487         if (other->meta.load_state != UNIT_STUB)
 488                 if (UNIT_VTABLE(other)->done)
 489                         UNIT_VTABLE(other)->done(other);
 490
 491         unit_add_to_dbus_queue(u);
 492         unit_add_to_cleanup_queue(other);
 493
 494         return 0;
 495 }
 496
 497 int unit_merge_by_name(Unit *u, const char *name) {
 498         Unit *other;
 499         int r;
 500         char *s = NULL;
 501
 502         assert(u);
 503         assert(name);
 504
 505         if (unit_name_is_template(name)) {
 506                 if (!u->meta.instance)
 507                         return -EINVAL;
 508
 509                 if (!(s = unit_name_replace_instance(name, u->meta.instance)))
 510                         return -ENOMEM;
 511
 512                 name = s;
 513         }
 514
 515         if (!(other = manager_get_unit(u->meta.manager, name)))
 516                 r = unit_add_name(u, name);
 517         else
 518                 r = unit_merge(u, other);
 519
 520         free(s);
 521         return r;
 522 }
 523
 524 Unit* unit_follow_merge(Unit *u) {
 525         assert(u);
 526
 527         while (u->meta.load_state == UNIT_MERGED)
 528                 assert_se(u = u->meta.merged_into);
 529
 530         return u;
 531 }
 532
 533 int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
 534         int r;
 535
 536         assert(u);
 537         assert(c);
 538
 539         if (c->std_output != EXEC_OUTPUT_KMSG &&
 540             c->std_output != EXEC_OUTPUT_SYSLOG &&
 541             c->std_error != EXEC_OUTPUT_KMSG &&
 542             c->std_error != EXEC_OUTPUT_SYSLOG)
 543                 return 0;
 544
 545         /* If syslog or kernel logging is requested, make sure our own
 546          * logging daemon is run first. */
 547
 548         if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 549                 return r;
 550
 551         if (u->meta.manager->running_as != MANAGER_SESSION)
 552                 if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
 553                         return r;
 554
 555         return 0;
 556 }
 557
 558 const char *unit_description(Unit *u) {
 559         assert(u);
 560
 561         if (u->meta.description)
 562                 return u->meta.description;
 563
 564         return u->meta.id;
 565 }
 566
 567 void unit_dump(Unit *u, FILE *f, const char *prefix) {
 568         char *t;
 569         UnitDependency d;
 570         Iterator i;
 571         char *p2;
 572         const char *prefix2;
 573         CGroupBonding *b;
 574         char
 575                 timestamp1[FORMAT_TIMESTAMP_MAX],
 576                 timestamp2[FORMAT_TIMESTAMP_MAX],
 577                 timestamp3[FORMAT_TIMESTAMP_MAX],
 578                 timestamp4[FORMAT_TIMESTAMP_MAX];
 579
 580         assert(u);
 581         assert(u->meta.type >= 0);
 582
 583         if (!prefix)
 584                 prefix = "";
 585         p2 = strappend(prefix, "\t");
 586         prefix2 = p2 ? p2 : prefix;
 587
 588         fprintf(f,
 589                 "%s-> Unit %s:\n"
 590                 "%s\tDescription: %s\n"
 591                 "%s\tInstance: %s\n"
 592                 "%s\tUnit Load State: %s\n"
 593                 "%s\tUnit Active State: %s\n"
 594                 "%s\tInactive Exit Timestamp: %s\n"
 595                 "%s\tActive Enter Timestamp: %s\n"
 596                 "%s\tActive Exit Timestamp: %s\n"
 597                 "%s\tInactive Enter Timestamp: %s\n"
 598                 "%s\tGC Check Good: %s\n"
 599                 "%s\tOnly By Dependency: %s\n",
 600                 prefix, u->meta.id,
 601                 prefix, unit_description(u),
 602                 prefix, strna(u->meta.instance),
 603                 prefix, unit_load_state_to_string(u->meta.load_state),
 604                 prefix, unit_active_state_to_string(unit_active_state(u)),
 605                 prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp.realtime)),
 606                 prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp.realtime)),
 607                 prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp.realtime)),
 608                 prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp.realtime)),
 609                 prefix, yes_no(unit_check_gc(u)),
 610                 prefix, yes_no(u->meta.only_by_dependency));
 611
 612         SET_FOREACH(t, u->meta.names, i)
 613                 fprintf(f, "%s\tName: %s\n", prefix, t);
 614
 615         if (u->meta.fragment_path)
 616                 fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
 617
 618         for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
 619                 Unit *other;
 620
 621                 SET_FOREACH(other, u->meta.dependencies[d], i)
 622                         fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
 623         }
 624
 625         if (u->meta.load_state == UNIT_LOADED) {
 626                 fprintf(f,
 627                         "%s\tRecursive Stop: %s\n"
 628                         "%s\tStop When Unneeded: %s\n",
 629                         prefix, yes_no(u->meta.recursive_stop),
 630                         prefix, yes_no(u->meta.stop_when_unneeded));
 631
 632                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
 633                         fprintf(f, "%s\tControlGroup: %s:%s\n",
 634                                 prefix, b->controller, b->path);
 635
 636                 if (UNIT_VTABLE(u)->dump)
 637                         UNIT_VTABLE(u)->dump(u, f, prefix2);
 638
 639         } else if (u->meta.load_state == UNIT_MERGED)
 640                 fprintf(f,
 641                         "%s\tMerged into: %s\n",
 642                         prefix, u->meta.merged_into->meta.id);
 643
 644         if (u->meta.job)
 645                 job_dump(u->meta.job, f, prefix2);
 646
 647         free(p2);
 648 }
 649
 650 /* Common implementation for multiple backends */
 651 int unit_load_fragment_and_dropin(Unit *u) {
 652         int r;
 653
 654         assert(u);
 655
 656         /* Load a .service file */
 657         if ((r = unit_load_fragment(u)) < 0)
 658                 return r;
 659
 660         if (u->meta.load_state == UNIT_STUB)
 661                 return -ENOENT;
 662
 663         /* Load drop-in directory data */
 664         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 665                 return r;
 666
 667         return 0;
 668 }
 669
 670 /* Common implementation for multiple backends */
 671 int unit_load_fragment_and_dropin_optional(Unit *u) {
 672         int r;
 673
 674         assert(u);
 675
 676         /* Same as unit_load_fragment_and_dropin(), but whether
 677          * something can be loaded or not doesn't matter. */
 678
 679         /* Load a .service file */
 680         if ((r = unit_load_fragment(u)) < 0)
 681                 return r;
 682
 683         if (u->meta.load_state == UNIT_STUB)
 684                 u->meta.load_state = UNIT_LOADED;
 685
 686         /* Load drop-in directory data */
 687         if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
 688                 return r;
 689
 690         return 0;
 691 }
 692
 693 /* Common implementation for multiple backends */
 694 int unit_load_nop(Unit *u) {
 695         assert(u);
 696
 697         if (u->meta.load_state == UNIT_STUB)
 698                 u->meta.load_state = UNIT_LOADED;
 699
 700         return 0;
 701 }
 702
 703 int unit_load(Unit *u) {
 704         int r;
 705
 706         assert(u);
 707
 708         if (u->meta.in_load_queue) {
 709                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 710                 u->meta.in_load_queue = false;
 711         }
 712
 713         if (u->meta.type == _UNIT_TYPE_INVALID)
 714                 return -EINVAL;
 715
 716         if (u->meta.load_state != UNIT_STUB)
 717                 return 0;
 718
 719         if (UNIT_VTABLE(u)->load)
 720                 if ((r = UNIT_VTABLE(u)->load(u)) < 0)
 721                         goto fail;
 722
 723         if (u->meta.load_state == UNIT_STUB) {
 724                 r = -ENOENT;
 725                 goto fail;
 726         }
 727
 728         assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
 729
 730         unit_add_to_dbus_queue(unit_follow_merge(u));
 731         unit_add_to_gc_queue(u);
 732
 733         return 0;
 734
 735 fail:
 736         u->meta.load_state = UNIT_FAILED;
 737         unit_add_to_dbus_queue(u);
 738
 739         log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
 740
 741         return r;
 742 }
 743
 744 /* Errors:
 745  *         -EBADR:     This unit type does not support starting.
 746  *         -EALREADY:  Unit is already started.
 747  *         -EAGAIN:    An operation is already in progress. Retry later.
 748  *         -ECANCELED: Too many requests for now.
 749  */
 750 int unit_start(Unit *u) {
 751         UnitActiveState state;
 752
 753         assert(u);
 754
 755         /* If this is already (being) started, then this will
 756          * succeed. Note that this will even succeed if this unit is
 757          * not startable by the user. This is relied on to detect when
 758          * we need to wait for units and when waiting is finished. */
 759         state = unit_active_state(u);
 760         if (UNIT_IS_ACTIVE_OR_RELOADING(state))
 761                 return -EALREADY;
 762
 763         /* If it is stopped, but we cannot start it, then fail */
 764         if (!UNIT_VTABLE(u)->start)
 765                 return -EBADR;
 766
 767         /* We don't suppress calls to ->start() here when we are
 768          * already starting, to allow this request to be used as a
 769          * "hurry up" call, for example when the unit is in some "auto
 770          * restart" state where it waits for a holdoff timer to elapse
 771          * before it will start again. */
 772
 773         unit_add_to_dbus_queue(u);
 774         return UNIT_VTABLE(u)->start(u);
 775 }
 776
 777 bool unit_can_start(Unit *u) {
 778         assert(u);
 779
 780         return !!UNIT_VTABLE(u)->start;
 781 }
 782
 783 /* Errors:
 784  *         -EBADR:    This unit type does not support stopping.
 785  *         -EALREADY: Unit is already stopped.
 786  *         -EAGAIN:   An operation is already in progress. Retry later.
 787  */
 788 int unit_stop(Unit *u) {
 789         UnitActiveState state;
 790
 791         assert(u);
 792
 793         state = unit_active_state(u);
 794         if (state == UNIT_INACTIVE)
 795                 return -EALREADY;
 796
 797         if (!UNIT_VTABLE(u)->stop)
 798                 return -EBADR;
 799
 800         unit_add_to_dbus_queue(u);
 801         return UNIT_VTABLE(u)->stop(u);
 802 }
 803
 804 /* Errors:
 805  *         -EBADR:    This unit type does not support reloading.
 806  *         -ENOEXEC:  Unit is not started.
 807  *         -EAGAIN:   An operation is already in progress. Retry later.
 808  */
 809 int unit_reload(Unit *u) {
 810         UnitActiveState state;
 811
 812         assert(u);
 813
 814         if (!unit_can_reload(u))
 815                 return -EBADR;
 816
 817         state = unit_active_state(u);
 818         if (unit_active_state(u) == UNIT_ACTIVE_RELOADING)
 819                 return -EALREADY;
 820
 821         if (unit_active_state(u) != UNIT_ACTIVE)
 822                 return -ENOEXEC;
 823
 824         unit_add_to_dbus_queue(u);
 825         return UNIT_VTABLE(u)->reload(u);
 826 }
 827
 828 bool unit_can_reload(Unit *u) {
 829         assert(u);
 830
 831         if (!UNIT_VTABLE(u)->reload)
 832                 return false;
 833
 834         if (!UNIT_VTABLE(u)->can_reload)
 835                 return true;
 836
 837         return UNIT_VTABLE(u)->can_reload(u);
 838 }
 839
 840 static void unit_check_uneeded(Unit *u) {
 841         Iterator i;
 842         Unit *other;
 843
 844         assert(u);
 845
 846         /* If this service shall be shut down when unneeded then do
 847          * so. */
 848
 849         if (!u->meta.stop_when_unneeded)
 850                 return;
 851
 852         if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
 853                 return;
 854
 855         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 856                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 857                         return;
 858
 859         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
 860                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 861                         return;
 862
 863         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
 864                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 865                         return;
 866
 867         log_debug("Service %s is not needed anymore. Stopping.", u->meta.id);
 868
 869         /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
 870         manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL);
 871 }
 872
 873 static void retroactively_start_dependencies(Unit *u) {
 874         Iterator i;
 875         Unit *other;
 876
 877         assert(u);
 878         assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
 879
 880         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 881                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 882                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 883
 884         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 885                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 886                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 887
 888         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 889                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 890                         manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
 891
 892         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 893                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 894                         manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
 895
 896         SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
 897                 if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
 898                         manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 899 }
 900
 901 static void retroactively_stop_dependencies(Unit *u) {
 902         Iterator i;
 903         Unit *other;
 904
 905         assert(u);
 906         assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
 907
 908         if (u->meta.recursive_stop) {
 909                 /* Pull down units need us recursively if enabled */
 910                 SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
 911                         if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 912                                 manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
 913         }
 914
 915         /* Garbage collect services that might not be needed anymore, if enabled */
 916         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
 917                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 918                         unit_check_uneeded(other);
 919         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
 920                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 921                         unit_check_uneeded(other);
 922         SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
 923                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 924                         unit_check_uneeded(other);
 925         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
 926                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 927                         unit_check_uneeded(other);
 928         SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
 929                 if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
 930                         unit_check_uneeded(other);
 931 }
 932
 933 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
 934         bool unexpected = false;
 935         timestamp ts;
 936
 937         assert(u);
 938         assert(os < _UNIT_ACTIVE_STATE_MAX);
 939         assert(ns < _UNIT_ACTIVE_STATE_MAX);
 940
 941         /* Note that this is called for all low-level state changes,
 942          * even if they might map to the same high-level
 943          * UnitActiveState! That means that ns == os is OK an expected
 944          * behaviour here. For example: if a mount point is remounted
 945          * this function will be called too and the utmp code below
 946          * relies on that! */
 947
 948         timestamp_get(&ts);
 949
 950         if (os == UNIT_INACTIVE && ns != UNIT_INACTIVE)
 951                 u->meta.inactive_exit_timestamp = ts;
 952         else if (os != UNIT_INACTIVE && ns == UNIT_INACTIVE)
 953                 u->meta.inactive_enter_timestamp = ts;
 954
 955         if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
 956                 u->meta.active_enter_timestamp = ts;
 957         else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
 958                 u->meta.active_exit_timestamp = ts;
 959
 960         timer_unit_notify(u, ns);
 961         path_unit_notify(u, ns);
 962
 963         if (u->meta.job) {
 964
 965                 if (u->meta.job->state == JOB_WAITING)
 966
 967                         /* So we reached a different state for this
 968                          * job. Let's see if we can run it now if it
 969                          * failed previously due to EAGAIN. */
 970                         job_add_to_run_queue(u->meta.job);
 971
 972                 else {
 973                         assert(u->meta.job->state == JOB_RUNNING);
 974
 975                         /* Let's check whether this state change
 976                          * constitutes a finished job, or maybe
 977                          * cotradicts a running job and hence needs to
 978                          * invalidate jobs. */
 979
 980                         switch (u->meta.job->type) {
 981
 982                         case JOB_START:
 983                         case JOB_VERIFY_ACTIVE:
 984
 985                                 if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
 986                                         job_finish_and_invalidate(u->meta.job, true);
 987                                 else if (ns != UNIT_ACTIVATING) {
 988                                         unexpected = true;
 989                                         job_finish_and_invalidate(u->meta.job, false);
 990                                 }
 991
 992                                 break;
 993
 994                         case JOB_RELOAD:
 995                         case JOB_RELOAD_OR_START:
 996
 997                                 if (ns == UNIT_ACTIVE)
 998                                         job_finish_and_invalidate(u->meta.job, true);
 999                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_ACTIVE_RELOADING) {
1000                                         unexpected = true;
1001                                         job_finish_and_invalidate(u->meta.job, false);
1002                                 }
1003
1004                                 break;
1005
1006                         case JOB_STOP:
1007                         case JOB_RESTART:
1008                         case JOB_TRY_RESTART:
1009
1010                                 if (ns == UNIT_INACTIVE)
1011                                         job_finish_and_invalidate(u->meta.job, true);
1012                                 else if (ns != UNIT_DEACTIVATING) {
1013                                         unexpected = true;
1014                                         job_finish_and_invalidate(u->meta.job, false);
1015                                 }
1016
1017                                 break;
1018
1019                         default:
1020                                 assert_not_reached("Job type unknown");
1021                         }
1022                 }
1023         }
1024
1025         /* If this state change happened without being requested by a
1026          * job, then let's retroactively start or stop dependencies */
1027
1028         if (unexpected) {
1029                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1030                         retroactively_start_dependencies(u);
1031                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1032                         retroactively_stop_dependencies(u);
1033         }
1034
1035         /* Some names are special */
1036         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1037                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1038                         /* The bus just might have become available,
1039                          * hence try to connect to it, if we aren't
1040                          * yet connected. */
1041                         bus_init_system(u->meta.manager);
1042                         bus_init_api(u->meta.manager);
1043                 }
1044
1045                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1046                         /* The syslog daemon just might have become
1047                          * available, hence try to connect to it, if
1048                          * we aren't yet connected. */
1049                         log_open();
1050
1051                 if (u->meta.type == UNIT_MOUNT)
1052                         /* Another directory became available, let's
1053                          * check if that is enough to write our utmp
1054                          * entry. */
1055                         manager_write_utmp_reboot(u->meta.manager);
1056
1057                 if (u->meta.type == UNIT_TARGET)
1058                         /* A target got activated, maybe this is a runlevel? */
1059                         manager_write_utmp_runlevel(u->meta.manager, u);
1060
1061         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1062
1063                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1064                         /* The syslog daemon might just have
1065                          * terminated, hence try to disconnect from
1066                          * it. */
1067                         log_close_syslog();
1068
1069                 /* We don't care about D-Bus here, since we'll get an
1070                  * asynchronous notification for it anyway. */
1071         }
1072
1073         /* Maybe we finished startup and are now ready for being
1074          * stopped because unneeded? */
1075         unit_check_uneeded(u);
1076
1077         unit_add_to_dbus_queue(u);
1078         unit_add_to_gc_queue(u);
1079 }
1080
1081 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1082         struct epoll_event ev;
1083
1084         assert(u);
1085         assert(fd >= 0);
1086         assert(w);
1087         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1088
1089         zero(ev);
1090         ev.data.ptr = w;
1091         ev.events = events;
1092
1093         if (epoll_ctl(u->meta.manager->epoll_fd,
1094                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1095                       fd,
1096                       &ev) < 0)
1097                 return -errno;
1098
1099         w->fd = fd;
1100         w->type = WATCH_FD;
1101         w->data.unit = u;
1102
1103         return 0;
1104 }
1105
1106 void unit_unwatch_fd(Unit *u, Watch *w) {
1107         assert(u);
1108         assert(w);
1109
1110         if (w->type == WATCH_INVALID)
1111                 return;
1112
1113         assert(w->type == WATCH_FD);
1114         assert(w->data.unit == u);
1115         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1116
1117         w->fd = -1;
1118         w->type = WATCH_INVALID;
1119         w->data.unit = NULL;
1120 }
1121
1122 int unit_watch_pid(Unit *u, pid_t pid) {
1123         assert(u);
1124         assert(pid >= 1);
1125
1126         /* Watch a specific PID. We only support one unit watching
1127          * each PID for now. */
1128
1129         return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1130 }
1131
1132 void unit_unwatch_pid(Unit *u, pid_t pid) {
1133         assert(u);
1134         assert(pid >= 1);
1135
1136         hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1137 }
1138
1139 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1140         struct itimerspec its;
1141         int flags, fd;
1142         bool ours;
1143
1144         assert(u);
1145         assert(w);
1146         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1147
1148         /* This will try to reuse the old timer if there is one */
1149
1150         if (w->type == WATCH_TIMER) {
1151                 ours = false;
1152                 fd = w->fd;
1153         } else {
1154                 ours = true;
1155                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1156                         return -errno;
1157         }
1158
1159         zero(its);
1160
1161         if (delay <= 0) {
1162                 /* Set absolute time in the past, but not 0, since we
1163                  * don't want to disarm the timer */
1164                 its.it_value.tv_sec = 0;
1165                 its.it_value.tv_nsec = 1;
1166
1167                 flags = TFD_TIMER_ABSTIME;
1168         } else {
1169                 timespec_store(&its.it_value, delay);
1170                 flags = 0;
1171         }
1172
1173         /* This will also flush the elapse counter */
1174         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1175                 goto fail;
1176
1177         if (w->type == WATCH_INVALID) {
1178                 struct epoll_event ev;
1179
1180                 zero(ev);
1181                 ev.data.ptr = w;
1182                 ev.events = EPOLLIN;
1183
1184                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1185                         goto fail;
1186         }
1187
1188         w->fd = fd;
1189         w->type = WATCH_TIMER;
1190         w->data.unit = u;
1191
1192         return 0;
1193
1194 fail:
1195         if (ours)
1196                 close_nointr_nofail(fd);
1197
1198         return -errno;
1199 }
1200
1201 void unit_unwatch_timer(Unit *u, Watch *w) {
1202         assert(u);
1203         assert(w);
1204
1205         if (w->type == WATCH_INVALID)
1206                 return;
1207
1208         assert(w->type == WATCH_TIMER && w->data.unit == u);
1209
1210         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1211         close_nointr_nofail(w->fd);
1212
1213         w->fd = -1;
1214         w->type = WATCH_INVALID;
1215         w->data.unit = NULL;
1216 }
1217
1218 bool unit_job_is_applicable(Unit *u, JobType j) {
1219         assert(u);
1220         assert(j >= 0 && j < _JOB_TYPE_MAX);
1221
1222         switch (j) {
1223
1224         case JOB_VERIFY_ACTIVE:
1225         case JOB_START:
1226                 return true;
1227
1228         case JOB_STOP:
1229         case JOB_RESTART:
1230         case JOB_TRY_RESTART:
1231                 return unit_can_start(u);
1232
1233         case JOB_RELOAD:
1234                 return unit_can_reload(u);
1235
1236         case JOB_RELOAD_OR_START:
1237                 return unit_can_reload(u) && unit_can_start(u);
1238
1239         default:
1240                 assert_not_reached("Invalid job type");
1241         }
1242 }
1243
1244 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1245
1246         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1247                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1248                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1249                 [UNIT_WANTS] = UNIT_WANTED_BY,
1250                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1251                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1252                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1253                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1254                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1255                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1256                 [UNIT_BEFORE] = UNIT_AFTER,
1257                 [UNIT_AFTER] = UNIT_BEFORE,
1258                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1259                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1260         };
1261         int r, q = 0, v = 0, w = 0;
1262
1263         assert(u);
1264         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1265         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1266         assert(other);
1267
1268         /* We won't allow dependencies on ourselves. We will not
1269          * consider them an error however. */
1270         if (u == other)
1271                 return 0;
1272
1273         if (UNIT_VTABLE(u)->no_requires &&
1274             (d == UNIT_REQUIRES ||
1275              d == UNIT_REQUIRES_OVERRIDABLE ||
1276              d == UNIT_REQUISITE ||
1277              d == UNIT_REQUISITE_OVERRIDABLE)) {
1278                     return -EINVAL;
1279         }
1280
1281         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1282             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1283                 return r;
1284
1285         if (add_reference)
1286                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1287                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1288                         return r;
1289
1290         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1291                 return q;
1292
1293         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1294                 r = v;
1295                 goto fail;
1296         }
1297
1298         if (add_reference) {
1299                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1300                         r = w;
1301                         goto fail;
1302                 }
1303
1304                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1305                         goto fail;
1306         }
1307
1308         unit_add_to_dbus_queue(u);
1309         return 0;
1310
1311 fail:
1312         if (q > 0)
1313                 set_remove(u->meta.dependencies[d], other);
1314
1315         if (v > 0)
1316                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1317
1318         if (w > 0)
1319                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1320
1321         return r;
1322 }
1323
1324 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1325         char *s;
1326
1327         assert(u);
1328         assert(name || path);
1329
1330         if (!name)
1331                 name = file_name_from_path(path);
1332
1333         if (!unit_name_is_template(name)) {
1334                 *p = NULL;
1335                 return name;
1336         }
1337
1338         if (u->meta.instance)
1339                 s = unit_name_replace_instance(name, u->meta.instance);
1340         else {
1341                 char *i;
1342
1343                 if (!(i = unit_name_to_prefix(u->meta.id)))
1344                         return NULL;
1345
1346                 s = unit_name_replace_instance(name, i);
1347                 free(i);
1348         }
1349
1350         if (!s)
1351                 return NULL;
1352
1353         *p = s;
1354         return s;
1355 }
1356
1357 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1358         Unit *other;
1359         int r;
1360         char *s;
1361
1362         assert(u);
1363         assert(name || path);
1364
1365         if (!(name = resolve_template(u, name, path, &s)))
1366                 return -ENOMEM;
1367
1368         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1369                 goto finish;
1370
1371         r = unit_add_dependency(u, d, other, add_reference);
1372
1373 finish:
1374         free(s);
1375         return r;
1376 }
1377
1378 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1379         Unit *other;
1380         int r;
1381         char *s;
1382
1383         assert(u);
1384         assert(name || path);
1385
1386         if (!(name = resolve_template(u, name, path, &s)))
1387                 return -ENOMEM;
1388
1389         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1390                 goto finish;
1391
1392         r = unit_add_dependency(other, d, u, add_reference);
1393
1394 finish:
1395         free(s);
1396         return r;
1397 }
1398
1399 int set_unit_path(const char *p) {
1400         char *cwd, *c;
1401         int r;
1402
1403         /* This is mostly for debug purposes */
1404
1405         if (path_is_absolute(p)) {
1406                 if (!(c = strdup(p)))
1407                         return -ENOMEM;
1408         } else {
1409                 if (!(cwd = get_current_dir_name()))
1410                         return -errno;
1411
1412                 r = asprintf(&c, "%s/%s", cwd, p);
1413                 free(cwd);
1414
1415                 if (r < 0)
1416                         return -ENOMEM;
1417         }
1418
1419         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1420                 r = -errno;
1421                 free(c);
1422                 return r;
1423         }
1424
1425         return 0;
1426 }
1427
1428 char *unit_dbus_path(Unit *u) {
1429         char *p, *e;
1430
1431         assert(u);
1432
1433         if (!(e = bus_path_escape(u->meta.id)))
1434                 return NULL;
1435
1436         if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
1437                 free(e);
1438                 return NULL;
1439         }
1440
1441         free(e);
1442         return p;
1443 }
1444
1445 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1446         CGroupBonding *l;
1447         int r;
1448
1449         assert(u);
1450         assert(b);
1451         assert(b->path);
1452
1453         /* Ensure this hasn't been added yet */
1454         assert(!b->unit);
1455
1456         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1457         LIST_PREPEND(CGroupBonding, by_path, l, b);
1458
1459         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1460                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1461                 return r;
1462         }
1463
1464         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1465         b->unit = u;
1466
1467         return 0;
1468 }
1469
1470 static char *default_cgroup_path(Unit *u) {
1471         char *p;
1472         int r;
1473
1474         assert(u);
1475
1476         if (u->meta.instance) {
1477                 char *t;
1478
1479                 if (!(t = unit_name_template(u->meta.id)))
1480                         return NULL;
1481
1482                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1483                 free(t);
1484         } else
1485                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1486
1487         return r < 0 ? NULL : p;
1488 }
1489
1490 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1491         size_t n;
1492         char *controller = NULL, *path = NULL;
1493         CGroupBonding *b = NULL;
1494         int r;
1495
1496         assert(u);
1497         assert(name);
1498
1499         /* Detect controller name */
1500         n = strcspn(name, ":");
1501
1502         if (name[n] == 0 ||
1503             (name[n] == ':' && name[n+1] == 0)) {
1504
1505                 /* Only controller name, no path? */
1506
1507                 if (!(path = default_cgroup_path(u)))
1508                         return -ENOMEM;
1509
1510         } else {
1511                 const char *p;
1512
1513                 /* Controller name, and path. */
1514                 p = name+n+1;
1515
1516                 if (!path_is_absolute(p))
1517                         return -EINVAL;
1518
1519                 if (!(path = strdup(p)))
1520                         return -ENOMEM;
1521         }
1522
1523         if (n > 0)
1524                 controller = strndup(name, n);
1525         else
1526                 controller = strdup(u->meta.manager->cgroup_controller);
1527
1528         if (!controller) {
1529                 r = -ENOMEM;
1530                 goto fail;
1531         }
1532
1533         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1534                 r = -EEXIST;
1535                 goto fail;
1536         }
1537
1538         if (!(b = new0(CGroupBonding, 1))) {
1539                 r = -ENOMEM;
1540                 goto fail;
1541         }
1542
1543         b->controller = controller;
1544         b->path = path;
1545         b->only_us = false;
1546         b->clean_up = false;
1547
1548         if ((r = unit_add_cgroup(u, b)) < 0)
1549                 goto fail;
1550
1551         return 0;
1552
1553 fail:
1554         free(path);
1555         free(controller);
1556         free(b);
1557
1558         return r;
1559 }
1560
1561 int unit_add_default_cgroup(Unit *u) {
1562         CGroupBonding *b;
1563         int r = -ENOMEM;
1564
1565         assert(u);
1566
1567         /* Adds in the default cgroup data, if it wasn't specified yet */
1568
1569         if (unit_get_default_cgroup(u))
1570                 return 0;
1571
1572         if (!(b = new0(CGroupBonding, 1)))
1573                 return -ENOMEM;
1574
1575         if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
1576                 goto fail;
1577
1578         if (!(b->path = default_cgroup_path(u)))
1579                 goto fail;
1580
1581         b->clean_up = true;
1582         b->only_us = true;
1583
1584         if ((r = unit_add_cgroup(u, b)) < 0)
1585                 goto fail;
1586
1587         return 0;
1588
1589 fail:
1590         free(b->path);
1591         free(b->controller);
1592         free(b);
1593
1594         return r;
1595 }
1596
1597 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1598         assert(u);
1599
1600         return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
1601 }
1602
1603 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1604         char *t;
1605         int r;
1606
1607         assert(u);
1608         assert(type);
1609         assert(_found);
1610
1611         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1612                 return -ENOMEM;
1613
1614         assert(!unit_has_name(u, t));
1615
1616         r = manager_load_unit(u->meta.manager, t, NULL, _found);
1617         free(t);
1618
1619         assert(r < 0 || *_found != u);
1620
1621         return r;
1622 }
1623
1624 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1625         Unit *found;
1626         char *t;
1627
1628         assert(u);
1629         assert(type);
1630         assert(_found);
1631
1632         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1633                 return -ENOMEM;
1634
1635         assert(!unit_has_name(u, t));
1636
1637         found = manager_get_unit(u->meta.manager, t);
1638         free(t);
1639
1640         if (!found)
1641                 return -ENOENT;
1642
1643         *_found = found;
1644         return 0;
1645 }
1646
1647 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1648         Unit *u = userdata;
1649         assert(u);
1650
1651         return unit_name_to_prefix_and_instance(u->meta.id);
1652 }
1653
1654 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1655         Unit *u = userdata;
1656         assert(u);
1657
1658         return unit_name_to_prefix(u->meta.id);
1659 }
1660
1661 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1662         Unit *u = userdata;
1663         char *p, *r;
1664
1665         assert(u);
1666
1667         if (!(p = unit_name_to_prefix(u->meta.id)))
1668                 return NULL;
1669
1670         r = unit_name_unescape(p);
1671         free(p);
1672
1673         return r;
1674 }
1675
1676 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1677         Unit *u = userdata;
1678         assert(u);
1679
1680         if (u->meta.instance)
1681                 return unit_name_unescape(u->meta.instance);
1682
1683         return strdup("");
1684 }
1685
1686 char *unit_name_printf(Unit *u, const char* format) {
1687
1688         /*
1689          * This will use the passed string as format string and
1690          * replace the following specifiers:
1691          *
1692          * %n: the full id of the unit                 (foo@bar.waldo)
1693          * %N: the id of the unit without the suffix   (foo@bar)
1694          * %p: the prefix                              (foo)
1695          * %i: the instance                            (bar)
1696          */
1697
1698         const Specifier table[] = {
1699                 { 'n', specifier_string,              u->meta.id },
1700                 { 'N', specifier_prefix_and_instance, NULL },
1701                 { 'p', specifier_prefix,              NULL },
1702                 { 'i', specifier_string,              u->meta.instance },
1703                 { 0, NULL, NULL }
1704         };
1705
1706         assert(u);
1707         assert(format);
1708
1709         return specifier_printf(format, table, u);
1710 }
1711
1712 char *unit_full_printf(Unit *u, const char *format) {
1713
1714         /* This is similar to unit_name_printf() but also supports
1715          * unescaping */
1716
1717         const Specifier table[] = {
1718                 { 'n', specifier_string,              u->meta.id },
1719                 { 'N', specifier_prefix_and_instance, NULL },
1720                 { 'p', specifier_prefix,              NULL },
1721                 { 'P', specifier_prefix_unescaped,    NULL },
1722                 { 'i', specifier_string,              u->meta.instance },
1723                 { 'I', specifier_instance_unescaped,  NULL },
1724                 { 0, NULL, NULL }
1725         };
1726
1727         assert(u);
1728         assert(format);
1729
1730         return specifier_printf(format, table, u);
1731 }
1732
1733 char **unit_full_printf_strv(Unit *u, char **l) {
1734         size_t n;
1735         char **r, **i, **j;
1736
1737         /* Applies unit_full_printf to every entry in l */
1738
1739         assert(u);
1740
1741         n = strv_length(l);
1742         if (!(r = new(char*, n+1)))
1743                 return NULL;
1744
1745         for (i = l, j = r; *i; i++, j++)
1746                 if (!(*j = unit_full_printf(u, *i)))
1747                         goto fail;
1748
1749         *j = NULL;
1750         return r;
1751
1752 fail:
1753         j--;
1754         while (j >= r)
1755                 free(*j);
1756
1757         free(r);
1758
1759         return NULL;
1760 }
1761
1762 int unit_watch_bus_name(Unit *u, const char *name) {
1763         assert(u);
1764         assert(name);
1765
1766         /* Watch a specific name on the bus. We only support one unit
1767          * watching each name for now. */
1768
1769         return hashmap_put(u->meta.manager->watch_bus, name, u);
1770 }
1771
1772 void unit_unwatch_bus_name(Unit *u, const char *name) {
1773         assert(u);
1774         assert(name);
1775
1776         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1777 }
1778
1779 bool unit_can_serialize(Unit *u) {
1780         assert(u);
1781
1782         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1783 }
1784
1785 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1786         int r;
1787
1788         assert(u);
1789         assert(f);
1790         assert(fds);
1791
1792         if (!unit_can_serialize(u))
1793                 return 0;
1794
1795         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1796                 return r;
1797
1798         if (u->meta.job)
1799                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1800
1801         /* End marker */
1802         fputc('\n', f);
1803         return 0;
1804 }
1805
1806 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1807         va_list ap;
1808
1809         assert(u);
1810         assert(f);
1811         assert(key);
1812         assert(format);
1813
1814         fputs(key, f);
1815         fputc('=', f);
1816
1817         va_start(ap, format);
1818         vfprintf(f, format, ap);
1819         va_end(ap);
1820
1821         fputc('\n', f);
1822 }
1823
1824 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1825         assert(u);
1826         assert(f);
1827         assert(key);
1828         assert(value);
1829
1830         fprintf(f, "%s=%s\n", key, value);
1831 }
1832
1833 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1834         int r;
1835
1836         assert(u);
1837         assert(f);
1838         assert(fds);
1839
1840         if (!unit_can_serialize(u))
1841                 return 0;
1842
1843         for (;;) {
1844                 char line[1024], *l, *v;
1845                 size_t k;
1846
1847                 if (!fgets(line, sizeof(line), f)) {
1848                         if (feof(f))
1849                                 return 0;
1850                         return -errno;
1851                 }
1852
1853                 l = strstrip(line);
1854
1855                 /* End marker */
1856                 if (l[0] == 0)
1857                         return 0;
1858
1859                 k = strcspn(l, "=");
1860
1861                 if (l[k] == '=') {
1862                         l[k] = 0;
1863                         v = l+k+1;
1864                 } else
1865                         v = l+k;
1866
1867                 if (streq(l, "job")) {
1868                         JobType type;
1869
1870                         if ((type = job_type_from_string(v)) < 0)
1871                                 log_debug("Failed to parse job type value %s", v);
1872                         else
1873                                 u->meta.deserialized_job = type;
1874
1875                         continue;
1876                 }
1877
1878                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1879                         return r;
1880         }
1881 }
1882
1883 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1884         Unit *device;
1885         char *e;
1886         int r;
1887
1888         assert(u);
1889
1890         if (!what)
1891                 return 0;
1892
1893         /* Adds in links to the device node that this unit is based on */
1894
1895         if (!is_device_path(what))
1896                 return 0;
1897
1898         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1899                 return -ENOMEM;
1900
1901         r = manager_load_unit(u->meta.manager, e, NULL, &device);
1902         free(e);
1903
1904         if (r < 0)
1905                 return r;
1906
1907         if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
1908                 return r;
1909
1910         if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
1911                 return r;
1912
1913         if (wants)
1914                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1915                         return r;
1916
1917         return 0;
1918 }
1919
1920 int unit_coldplug(Unit *u) {
1921         int r;
1922
1923         assert(u);
1924
1925         if (UNIT_VTABLE(u)->coldplug)
1926                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
1927                         return r;
1928
1929         if (u->meta.deserialized_job >= 0) {
1930                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL)) < 0)
1931                         return r;
1932
1933                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
1934         }
1935
1936         return 0;
1937 }
1938
1939 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
1940         [UNIT_SERVICE] = "service",
1941         [UNIT_TIMER] = "timer",
1942         [UNIT_SOCKET] = "socket",
1943         [UNIT_TARGET] = "target",
1944         [UNIT_DEVICE] = "device",
1945         [UNIT_MOUNT] = "mount",
1946         [UNIT_AUTOMOUNT] = "automount",
1947         [UNIT_SNAPSHOT] = "snapshot",
1948         [UNIT_SWAP] = "swap"
1949 };
1950
1951 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
1952
1953 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
1954         [UNIT_STUB] = "stub",
1955         [UNIT_LOADED] = "loaded",
1956         [UNIT_FAILED] = "failed",
1957         [UNIT_MERGED] = "merged"
1958 };
1959
1960 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
1961
1962 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
1963         [UNIT_ACTIVE] = "active",
1964         [UNIT_INACTIVE] = "inactive",
1965         [UNIT_ACTIVATING] = "activating",
1966         [UNIT_DEACTIVATING] = "deactivating"
1967 };
1968
1969 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
1970
1971 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
1972         [UNIT_REQUIRES] = "Requires",
1973         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
1974         [UNIT_WANTS] = "Wants",
1975         [UNIT_REQUISITE] = "Requisite",
1976         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
1977         [UNIT_REQUIRED_BY] = "RequiredBy",
1978         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
1979         [UNIT_WANTED_BY] = "WantedBy",
1980         [UNIT_CONFLICTS] = "Conflicts",
1981         [UNIT_BEFORE] = "Before",
1982         [UNIT_AFTER] = "After",
1983         [UNIT_REFERENCES] = "References",
1984         [UNIT_REFERENCED_BY] = "ReferencedBy"
1985 };
1986
1987 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
1988
1989 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
1990         [KILL_CONTROL_GROUP] = "control-group",
1991         [KILL_PROCESS_GROUP] = "process-group",
1992         [KILL_PROCESS] = "process",
1993         [KILL_NONE] = "none"
1994 };
1995
1996 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);