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