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