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         if (u->meta.load_state != UNIT_STUB)
 323                 if (UNIT_VTABLE(u)->done)
 324                         UNIT_VTABLE(u)->done(u);
 325
 326         /* Detach from next 'bigger' objects */
 327         SET_FOREACH(t, u->meta.names, i)
 328                 hashmap_remove_value(u->meta.manager->units, t, u);
 329
 330         if (u->meta.type != _UNIT_TYPE_INVALID)
 331                 LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
 332
 333         if (u->meta.in_load_queue)
 334                 LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
 335
 336         if (u->meta.in_dbus_queue)
 337                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 338
 339         if (u->meta.in_cleanup_queue)
 340                 LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
 341
 342         if (u->meta.in_gc_queue) {
 343                 LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
 344                 u->meta.manager->n_in_gc_queue--;
 345         }
 346
 347         /* Free data and next 'smaller' objects */
 348         if (u->meta.job)
 349                 job_free(u->meta.job);
 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
 973                 /* Let's check whether this state change constitutes a
 974                  * finished job, or maybe cotradicts a running job and
 975                  * hence needs to invalidate jobs. */
 976
 977                 switch (u->meta.job->type) {
 978
 979                 case JOB_START:
 980                 case JOB_VERIFY_ACTIVE:
 981
 982                         if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
 983                                 job_finish_and_invalidate(u->meta.job, true);
 984                         else if (u->meta.job->state == JOB_RUNNING && ns != UNIT_ACTIVATING) {
 985                                 unexpected = true;
 986                                 job_finish_and_invalidate(u->meta.job, false);
 987                         }
 988
 989                         break;
 990
 991                 case JOB_RELOAD:
 992                 case JOB_RELOAD_OR_START:
 993
 994                         if (u->meta.job->state == JOB_RUNNING) {
 995                                 if (ns == UNIT_ACTIVE)
 996                                         job_finish_and_invalidate(u->meta.job, true);
 997                                 else if (ns != UNIT_ACTIVATING && ns != UNIT_ACTIVE_RELOADING) {
 998                                         unexpected = true;
 999                                         job_finish_and_invalidate(u->meta.job, false);
1000                                 }
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 (u->meta.job->state == JOB_RUNNING && 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         /* If this state change happened without being requested by a
1024          * job, then let's retroactively start or stop dependencies */
1025
1026         if (unexpected) {
1027                 if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
1028                         retroactively_start_dependencies(u);
1029                 else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
1030                         retroactively_stop_dependencies(u);
1031         }
1032
1033         /* Some names are special */
1034         if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1035                 if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1036                         /* The bus just might have become available,
1037                          * hence try to connect to it, if we aren't
1038                          * yet connected. */
1039                         bus_init_system(u->meta.manager);
1040                         bus_init_api(u->meta.manager);
1041                 }
1042
1043                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1044                         /* The syslog daemon just might have become
1045                          * available, hence try to connect to it, if
1046                          * we aren't yet connected. */
1047                         log_open();
1048
1049                 if (u->meta.type == UNIT_MOUNT)
1050                         /* Another directory became available, let's
1051                          * check if that is enough to write our utmp
1052                          * entry. */
1053                         manager_write_utmp_reboot(u->meta.manager);
1054
1055                 if (u->meta.type == UNIT_TARGET)
1056                         /* A target got activated, maybe this is a runlevel? */
1057                         manager_write_utmp_runlevel(u->meta.manager, u);
1058
1059         } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
1060
1061                 if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
1062                         /* The syslog daemon might just have
1063                          * terminated, hence try to disconnect from
1064                          * it. */
1065                         log_close_syslog();
1066
1067                 /* We don't care about D-Bus here, since we'll get an
1068                  * asynchronous notification for it anyway. */
1069         }
1070
1071         /* Maybe we finished startup and are now ready for being
1072          * stopped because unneeded? */
1073         unit_check_uneeded(u);
1074
1075         unit_add_to_dbus_queue(u);
1076         unit_add_to_gc_queue(u);
1077 }
1078
1079 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
1080         struct epoll_event ev;
1081
1082         assert(u);
1083         assert(fd >= 0);
1084         assert(w);
1085         assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
1086
1087         zero(ev);
1088         ev.data.ptr = w;
1089         ev.events = events;
1090
1091         if (epoll_ctl(u->meta.manager->epoll_fd,
1092                       w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
1093                       fd,
1094                       &ev) < 0)
1095                 return -errno;
1096
1097         w->fd = fd;
1098         w->type = WATCH_FD;
1099         w->data.unit = u;
1100
1101         return 0;
1102 }
1103
1104 void unit_unwatch_fd(Unit *u, Watch *w) {
1105         assert(u);
1106         assert(w);
1107
1108         if (w->type == WATCH_INVALID)
1109                 return;
1110
1111         assert(w->type == WATCH_FD);
1112         assert(w->data.unit == u);
1113         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1114
1115         w->fd = -1;
1116         w->type = WATCH_INVALID;
1117         w->data.unit = NULL;
1118 }
1119
1120 int unit_watch_pid(Unit *u, pid_t pid) {
1121         assert(u);
1122         assert(pid >= 1);
1123
1124         /* Watch a specific PID. We only support one unit watching
1125          * each PID for now. */
1126
1127         return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1128 }
1129
1130 void unit_unwatch_pid(Unit *u, pid_t pid) {
1131         assert(u);
1132         assert(pid >= 1);
1133
1134         hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
1135 }
1136
1137 int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
1138         struct itimerspec its;
1139         int flags, fd;
1140         bool ours;
1141
1142         assert(u);
1143         assert(w);
1144         assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
1145
1146         /* This will try to reuse the old timer if there is one */
1147
1148         if (w->type == WATCH_TIMER) {
1149                 ours = false;
1150                 fd = w->fd;
1151         } else {
1152                 ours = true;
1153                 if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
1154                         return -errno;
1155         }
1156
1157         zero(its);
1158
1159         if (delay <= 0) {
1160                 /* Set absolute time in the past, but not 0, since we
1161                  * don't want to disarm the timer */
1162                 its.it_value.tv_sec = 0;
1163                 its.it_value.tv_nsec = 1;
1164
1165                 flags = TFD_TIMER_ABSTIME;
1166         } else {
1167                 timespec_store(&its.it_value, delay);
1168                 flags = 0;
1169         }
1170
1171         /* This will also flush the elapse counter */
1172         if (timerfd_settime(fd, flags, &its, NULL) < 0)
1173                 goto fail;
1174
1175         if (w->type == WATCH_INVALID) {
1176                 struct epoll_event ev;
1177
1178                 zero(ev);
1179                 ev.data.ptr = w;
1180                 ev.events = EPOLLIN;
1181
1182                 if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
1183                         goto fail;
1184         }
1185
1186         w->fd = fd;
1187         w->type = WATCH_TIMER;
1188         w->data.unit = u;
1189
1190         return 0;
1191
1192 fail:
1193         if (ours)
1194                 close_nointr_nofail(fd);
1195
1196         return -errno;
1197 }
1198
1199 void unit_unwatch_timer(Unit *u, Watch *w) {
1200         assert(u);
1201         assert(w);
1202
1203         if (w->type == WATCH_INVALID)
1204                 return;
1205
1206         assert(w->type == WATCH_TIMER && w->data.unit == u);
1207
1208         assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
1209         close_nointr_nofail(w->fd);
1210
1211         w->fd = -1;
1212         w->type = WATCH_INVALID;
1213         w->data.unit = NULL;
1214 }
1215
1216 bool unit_job_is_applicable(Unit *u, JobType j) {
1217         assert(u);
1218         assert(j >= 0 && j < _JOB_TYPE_MAX);
1219
1220         switch (j) {
1221
1222         case JOB_VERIFY_ACTIVE:
1223         case JOB_START:
1224                 return true;
1225
1226         case JOB_STOP:
1227         case JOB_RESTART:
1228         case JOB_TRY_RESTART:
1229                 return unit_can_start(u);
1230
1231         case JOB_RELOAD:
1232                 return unit_can_reload(u);
1233
1234         case JOB_RELOAD_OR_START:
1235                 return unit_can_reload(u) && unit_can_start(u);
1236
1237         default:
1238                 assert_not_reached("Invalid job type");
1239         }
1240 }
1241
1242 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
1243
1244         static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
1245                 [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
1246                 [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1247                 [UNIT_WANTS] = UNIT_WANTED_BY,
1248                 [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
1249                 [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
1250                 [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
1251                 [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
1252                 [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
1253                 [UNIT_CONFLICTS] = UNIT_CONFLICTS,
1254                 [UNIT_BEFORE] = UNIT_AFTER,
1255                 [UNIT_AFTER] = UNIT_BEFORE,
1256                 [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
1257                 [UNIT_REFERENCED_BY] = UNIT_REFERENCES
1258         };
1259         int r, q = 0, v = 0, w = 0;
1260
1261         assert(u);
1262         assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
1263         assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
1264         assert(other);
1265
1266         /* We won't allow dependencies on ourselves. We will not
1267          * consider them an error however. */
1268         if (u == other)
1269                 return 0;
1270
1271         if (UNIT_VTABLE(u)->no_requires &&
1272             (d == UNIT_REQUIRES ||
1273              d == UNIT_REQUIRES_OVERRIDABLE ||
1274              d == UNIT_REQUISITE ||
1275              d == UNIT_REQUISITE_OVERRIDABLE)) {
1276                     return -EINVAL;
1277         }
1278
1279         if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
1280             (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
1281                 return r;
1282
1283         if (add_reference)
1284                 if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
1285                     (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
1286                         return r;
1287
1288         if ((q = set_put(u->meta.dependencies[d], other)) < 0)
1289                 return q;
1290
1291         if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
1292                 r = v;
1293                 goto fail;
1294         }
1295
1296         if (add_reference) {
1297                 if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
1298                         r = w;
1299                         goto fail;
1300                 }
1301
1302                 if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
1303                         goto fail;
1304         }
1305
1306         unit_add_to_dbus_queue(u);
1307         return 0;
1308
1309 fail:
1310         if (q > 0)
1311                 set_remove(u->meta.dependencies[d], other);
1312
1313         if (v > 0)
1314                 set_remove(other->meta.dependencies[inverse_table[d]], u);
1315
1316         if (w > 0)
1317                 set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
1318
1319         return r;
1320 }
1321
1322 static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
1323         char *s;
1324
1325         assert(u);
1326         assert(name || path);
1327
1328         if (!name)
1329                 name = file_name_from_path(path);
1330
1331         if (!unit_name_is_template(name)) {
1332                 *p = NULL;
1333                 return name;
1334         }
1335
1336         if (u->meta.instance)
1337                 s = unit_name_replace_instance(name, u->meta.instance);
1338         else {
1339                 char *i;
1340
1341                 if (!(i = unit_name_to_prefix(u->meta.id)))
1342                         return NULL;
1343
1344                 s = unit_name_replace_instance(name, i);
1345                 free(i);
1346         }
1347
1348         if (!s)
1349                 return NULL;
1350
1351         *p = s;
1352         return s;
1353 }
1354
1355 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1356         Unit *other;
1357         int r;
1358         char *s;
1359
1360         assert(u);
1361         assert(name || path);
1362
1363         if (!(name = resolve_template(u, name, path, &s)))
1364                 return -ENOMEM;
1365
1366         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1367                 goto finish;
1368
1369         r = unit_add_dependency(u, d, other, add_reference);
1370
1371 finish:
1372         free(s);
1373         return r;
1374 }
1375
1376 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
1377         Unit *other;
1378         int r;
1379         char *s;
1380
1381         assert(u);
1382         assert(name || path);
1383
1384         if (!(name = resolve_template(u, name, path, &s)))
1385                 return -ENOMEM;
1386
1387         if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
1388                 goto finish;
1389
1390         r = unit_add_dependency(other, d, u, add_reference);
1391
1392 finish:
1393         free(s);
1394         return r;
1395 }
1396
1397 int set_unit_path(const char *p) {
1398         char *cwd, *c;
1399         int r;
1400
1401         /* This is mostly for debug purposes */
1402
1403         if (path_is_absolute(p)) {
1404                 if (!(c = strdup(p)))
1405                         return -ENOMEM;
1406         } else {
1407                 if (!(cwd = get_current_dir_name()))
1408                         return -errno;
1409
1410                 r = asprintf(&c, "%s/%s", cwd, p);
1411                 free(cwd);
1412
1413                 if (r < 0)
1414                         return -ENOMEM;
1415         }
1416
1417         if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
1418                 r = -errno;
1419                 free(c);
1420                 return r;
1421         }
1422
1423         return 0;
1424 }
1425
1426 char *unit_dbus_path(Unit *u) {
1427         char *p, *e;
1428
1429         assert(u);
1430
1431         if (!(e = bus_path_escape(u->meta.id)))
1432                 return NULL;
1433
1434         if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
1435                 free(e);
1436                 return NULL;
1437         }
1438
1439         free(e);
1440         return p;
1441 }
1442
1443 int unit_add_cgroup(Unit *u, CGroupBonding *b) {
1444         CGroupBonding *l;
1445         int r;
1446
1447         assert(u);
1448         assert(b);
1449         assert(b->path);
1450
1451         /* Ensure this hasn't been added yet */
1452         assert(!b->unit);
1453
1454         l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
1455         LIST_PREPEND(CGroupBonding, by_path, l, b);
1456
1457         if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
1458                 LIST_REMOVE(CGroupBonding, by_path, l, b);
1459                 return r;
1460         }
1461
1462         LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
1463         b->unit = u;
1464
1465         return 0;
1466 }
1467
1468 static char *default_cgroup_path(Unit *u) {
1469         char *p;
1470         int r;
1471
1472         assert(u);
1473
1474         if (u->meta.instance) {
1475                 char *t;
1476
1477                 if (!(t = unit_name_template(u->meta.id)))
1478                         return NULL;
1479
1480                 r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
1481                 free(t);
1482         } else
1483                 r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
1484
1485         return r < 0 ? NULL : p;
1486 }
1487
1488 int unit_add_cgroup_from_text(Unit *u, const char *name) {
1489         size_t n;
1490         char *controller = NULL, *path = NULL;
1491         CGroupBonding *b = NULL;
1492         int r;
1493
1494         assert(u);
1495         assert(name);
1496
1497         /* Detect controller name */
1498         n = strcspn(name, ":");
1499
1500         if (name[n] == 0 ||
1501             (name[n] == ':' && name[n+1] == 0)) {
1502
1503                 /* Only controller name, no path? */
1504
1505                 if (!(path = default_cgroup_path(u)))
1506                         return -ENOMEM;
1507
1508         } else {
1509                 const char *p;
1510
1511                 /* Controller name, and path. */
1512                 p = name+n+1;
1513
1514                 if (!path_is_absolute(p))
1515                         return -EINVAL;
1516
1517                 if (!(path = strdup(p)))
1518                         return -ENOMEM;
1519         }
1520
1521         if (n > 0)
1522                 controller = strndup(name, n);
1523         else
1524                 controller = strdup(u->meta.manager->cgroup_controller);
1525
1526         if (!controller) {
1527                 r = -ENOMEM;
1528                 goto fail;
1529         }
1530
1531         if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
1532                 r = -EEXIST;
1533                 goto fail;
1534         }
1535
1536         if (!(b = new0(CGroupBonding, 1))) {
1537                 r = -ENOMEM;
1538                 goto fail;
1539         }
1540
1541         b->controller = controller;
1542         b->path = path;
1543         b->only_us = false;
1544         b->clean_up = false;
1545
1546         if ((r = unit_add_cgroup(u, b)) < 0)
1547                 goto fail;
1548
1549         return 0;
1550
1551 fail:
1552         free(path);
1553         free(controller);
1554         free(b);
1555
1556         return r;
1557 }
1558
1559 int unit_add_default_cgroup(Unit *u) {
1560         CGroupBonding *b;
1561         int r = -ENOMEM;
1562
1563         assert(u);
1564
1565         /* Adds in the default cgroup data, if it wasn't specified yet */
1566
1567         if (unit_get_default_cgroup(u))
1568                 return 0;
1569
1570         if (!(b = new0(CGroupBonding, 1)))
1571                 return -ENOMEM;
1572
1573         if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
1574                 goto fail;
1575
1576         if (!(b->path = default_cgroup_path(u)))
1577                 goto fail;
1578
1579         b->clean_up = true;
1580         b->only_us = true;
1581
1582         if ((r = unit_add_cgroup(u, b)) < 0)
1583                 goto fail;
1584
1585         return 0;
1586
1587 fail:
1588         free(b->path);
1589         free(b->controller);
1590         free(b);
1591
1592         return r;
1593 }
1594
1595 CGroupBonding* unit_get_default_cgroup(Unit *u) {
1596         assert(u);
1597
1598         return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
1599 }
1600
1601 int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
1602         char *t;
1603         int r;
1604
1605         assert(u);
1606         assert(type);
1607         assert(_found);
1608
1609         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1610                 return -ENOMEM;
1611
1612         assert(!unit_has_name(u, t));
1613
1614         r = manager_load_unit(u->meta.manager, t, NULL, _found);
1615         free(t);
1616
1617         assert(r < 0 || *_found != u);
1618
1619         return r;
1620 }
1621
1622 int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
1623         Unit *found;
1624         char *t;
1625
1626         assert(u);
1627         assert(type);
1628         assert(_found);
1629
1630         if (!(t = unit_name_change_suffix(u->meta.id, type)))
1631                 return -ENOMEM;
1632
1633         assert(!unit_has_name(u, t));
1634
1635         found = manager_get_unit(u->meta.manager, t);
1636         free(t);
1637
1638         if (!found)
1639                 return -ENOENT;
1640
1641         *_found = found;
1642         return 0;
1643 }
1644
1645 static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
1646         Unit *u = userdata;
1647         assert(u);
1648
1649         return unit_name_to_prefix_and_instance(u->meta.id);
1650 }
1651
1652 static char *specifier_prefix(char specifier, void *data, void *userdata) {
1653         Unit *u = userdata;
1654         assert(u);
1655
1656         return unit_name_to_prefix(u->meta.id);
1657 }
1658
1659 static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
1660         Unit *u = userdata;
1661         char *p, *r;
1662
1663         assert(u);
1664
1665         if (!(p = unit_name_to_prefix(u->meta.id)))
1666                 return NULL;
1667
1668         r = unit_name_unescape(p);
1669         free(p);
1670
1671         return r;
1672 }
1673
1674 static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
1675         Unit *u = userdata;
1676         assert(u);
1677
1678         if (u->meta.instance)
1679                 return unit_name_unescape(u->meta.instance);
1680
1681         return strdup("");
1682 }
1683
1684 char *unit_name_printf(Unit *u, const char* format) {
1685
1686         /*
1687          * This will use the passed string as format string and
1688          * replace the following specifiers:
1689          *
1690          * %n: the full id of the unit                 (foo@bar.waldo)
1691          * %N: the id of the unit without the suffix   (foo@bar)
1692          * %p: the prefix                              (foo)
1693          * %i: the instance                            (bar)
1694          */
1695
1696         const Specifier table[] = {
1697                 { 'n', specifier_string,              u->meta.id },
1698                 { 'N', specifier_prefix_and_instance, NULL },
1699                 { 'p', specifier_prefix,              NULL },
1700                 { 'i', specifier_string,              u->meta.instance },
1701                 { 0, NULL, NULL }
1702         };
1703
1704         assert(u);
1705         assert(format);
1706
1707         return specifier_printf(format, table, u);
1708 }
1709
1710 char *unit_full_printf(Unit *u, const char *format) {
1711
1712         /* This is similar to unit_name_printf() but also supports
1713          * unescaping */
1714
1715         const Specifier table[] = {
1716                 { 'n', specifier_string,              u->meta.id },
1717                 { 'N', specifier_prefix_and_instance, NULL },
1718                 { 'p', specifier_prefix,              NULL },
1719                 { 'P', specifier_prefix_unescaped,    NULL },
1720                 { 'i', specifier_string,              u->meta.instance },
1721                 { 'I', specifier_instance_unescaped,  NULL },
1722                 { 0, NULL, NULL }
1723         };
1724
1725         assert(u);
1726         assert(format);
1727
1728         return specifier_printf(format, table, u);
1729 }
1730
1731 char **unit_full_printf_strv(Unit *u, char **l) {
1732         size_t n;
1733         char **r, **i, **j;
1734
1735         /* Applies unit_full_printf to every entry in l */
1736
1737         assert(u);
1738
1739         n = strv_length(l);
1740         if (!(r = new(char*, n+1)))
1741                 return NULL;
1742
1743         for (i = l, j = r; *i; i++, j++)
1744                 if (!(*j = unit_full_printf(u, *i)))
1745                         goto fail;
1746
1747         *j = NULL;
1748         return r;
1749
1750 fail:
1751         j--;
1752         while (j >= r)
1753                 free(*j);
1754
1755         free(r);
1756
1757         return NULL;
1758 }
1759
1760 int unit_watch_bus_name(Unit *u, const char *name) {
1761         assert(u);
1762         assert(name);
1763
1764         /* Watch a specific name on the bus. We only support one unit
1765          * watching each name for now. */
1766
1767         return hashmap_put(u->meta.manager->watch_bus, name, u);
1768 }
1769
1770 void unit_unwatch_bus_name(Unit *u, const char *name) {
1771         assert(u);
1772         assert(name);
1773
1774         hashmap_remove_value(u->meta.manager->watch_bus, name, u);
1775 }
1776
1777 bool unit_can_serialize(Unit *u) {
1778         assert(u);
1779
1780         return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
1781 }
1782
1783 int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
1784         int r;
1785
1786         assert(u);
1787         assert(f);
1788         assert(fds);
1789
1790         if (!unit_can_serialize(u))
1791                 return 0;
1792
1793         if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
1794                 return r;
1795
1796         if (u->meta.job)
1797                 unit_serialize_item(u, f, "job", job_type_to_string(u->meta.job->type));
1798
1799         /* End marker */
1800         fputc('\n', f);
1801         return 0;
1802 }
1803
1804 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
1805         va_list ap;
1806
1807         assert(u);
1808         assert(f);
1809         assert(key);
1810         assert(format);
1811
1812         fputs(key, f);
1813         fputc('=', f);
1814
1815         va_start(ap, format);
1816         vfprintf(f, format, ap);
1817         va_end(ap);
1818
1819         fputc('\n', f);
1820 }
1821
1822 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
1823         assert(u);
1824         assert(f);
1825         assert(key);
1826         assert(value);
1827
1828         fprintf(f, "%s=%s\n", key, value);
1829 }
1830
1831 int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
1832         int r;
1833
1834         assert(u);
1835         assert(f);
1836         assert(fds);
1837
1838         if (!unit_can_serialize(u))
1839                 return 0;
1840
1841         for (;;) {
1842                 char line[1024], *l, *v;
1843                 size_t k;
1844
1845                 if (!fgets(line, sizeof(line), f)) {
1846                         if (feof(f))
1847                                 return 0;
1848                         return -errno;
1849                 }
1850
1851                 l = strstrip(line);
1852
1853                 /* End marker */
1854                 if (l[0] == 0)
1855                         return 0;
1856
1857                 k = strcspn(l, "=");
1858
1859                 if (l[k] == '=') {
1860                         l[k] = 0;
1861                         v = l+k+1;
1862                 } else
1863                         v = l+k;
1864
1865                 if (streq(l, "job")) {
1866                         JobType type;
1867
1868                         if ((type = job_type_from_string(v)) < 0)
1869                                 log_debug("Failed to parse job type value %s", v);
1870                         else
1871                                 u->meta.deserialized_job = type;
1872
1873                         continue;
1874                 }
1875
1876                 if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
1877                         return r;
1878         }
1879 }
1880
1881 int unit_add_node_link(Unit *u, const char *what, bool wants) {
1882         Unit *device;
1883         char *e;
1884         int r;
1885
1886         assert(u);
1887
1888         if (!what)
1889                 return 0;
1890
1891         /* Adds in links to the device node that this unit is based on */
1892
1893         if (!is_device_path(what))
1894                 return 0;
1895
1896         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
1897                 return -ENOMEM;
1898
1899         r = manager_load_unit(u->meta.manager, e, NULL, &device);
1900         free(e);
1901
1902         if (r < 0)
1903                 return r;
1904
1905         if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
1906                 return r;
1907
1908         if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
1909                 return r;
1910
1911         if (wants)
1912                 if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
1913                         return r;
1914
1915         return 0;
1916 }
1917
1918 int unit_coldplug(Unit *u) {
1919         int r;
1920
1921         assert(u);
1922
1923         if (UNIT_VTABLE(u)->coldplug)
1924                 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
1925                         return r;
1926
1927         if (u->meta.deserialized_job >= 0) {
1928                 if ((r = manager_add_job(u->meta.manager, u->meta.deserialized_job, u, JOB_FAIL, false, NULL)) < 0)
1929                         return r;
1930
1931                 u->meta.deserialized_job = _JOB_TYPE_INVALID;
1932         }
1933
1934         return 0;
1935 }
1936
1937 static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
1938         [UNIT_SERVICE] = "service",
1939         [UNIT_TIMER] = "timer",
1940         [UNIT_SOCKET] = "socket",
1941         [UNIT_TARGET] = "target",
1942         [UNIT_DEVICE] = "device",
1943         [UNIT_MOUNT] = "mount",
1944         [UNIT_AUTOMOUNT] = "automount",
1945         [UNIT_SNAPSHOT] = "snapshot",
1946         [UNIT_SWAP] = "swap"
1947 };
1948
1949 DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
1950
1951 static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
1952         [UNIT_STUB] = "stub",
1953         [UNIT_LOADED] = "loaded",
1954         [UNIT_FAILED] = "failed",
1955         [UNIT_MERGED] = "merged"
1956 };
1957
1958 DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
1959
1960 static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
1961         [UNIT_ACTIVE] = "active",
1962         [UNIT_INACTIVE] = "inactive",
1963         [UNIT_ACTIVATING] = "activating",
1964         [UNIT_DEACTIVATING] = "deactivating"
1965 };
1966
1967 DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
1968
1969 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
1970         [UNIT_REQUIRES] = "Requires",
1971         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
1972         [UNIT_WANTS] = "Wants",
1973         [UNIT_REQUISITE] = "Requisite",
1974         [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
1975         [UNIT_REQUIRED_BY] = "RequiredBy",
1976         [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
1977         [UNIT_WANTED_BY] = "WantedBy",
1978         [UNIT_CONFLICTS] = "Conflicts",
1979         [UNIT_BEFORE] = "Before",
1980         [UNIT_AFTER] = "After",
1981         [UNIT_REFERENCES] = "References",
1982         [UNIT_REFERENCED_BY] = "ReferencedBy"
1983 };
1984
1985 DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
1986
1987 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
1988         [KILL_CONTROL_GROUP] = "control-group",
1989         [KILL_PROCESS_GROUP] = "process-group",
1990         [KILL_PROCESS] = "process",
1991         [KILL_NONE] = "none"
1992 };
1993
1994 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);