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