src/dbus-unit.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   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 <errno.h>
  23
  24 #include "dbus.h"
  25 #include "log.h"
  26 #include "dbus-unit.h"
  27 #include "bus-errors.h"
  28 #include "dbus-common.h"
  29
  30 const char bus_unit_interface[] _introspect_("Unit") = BUS_UNIT_INTERFACE;
  31
  32 #define INVALIDATING_PROPERTIES                 \
  33         "LoadState\0"                           \
  34         "ActiveState\0"                         \
  35         "SubState\0"                            \
  36         "InactiveExitTimestamp\0"               \
  37         "ActiveEnterTimestamp\0"                \
  38         "ActiveExitTimestamp\0"                 \
  39         "InactiveEnterTimestamp\0"              \
  40         "Job\0"                                 \
  41         "NeedDaemonReload\0"
  42
  43 int bus_unit_append_names(DBusMessageIter *i, const char *property, void *data) {
  44         char *t;
  45         Iterator j;
  46         DBusMessageIter sub;
  47         Unit *u = data;
  48
  49         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
  50                 return -ENOMEM;
  51
  52         SET_FOREACH(t, u->meta.names, j)
  53                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &t))
  54                         return -ENOMEM;
  55
  56         if (!dbus_message_iter_close_container(i, &sub))
  57                 return -ENOMEM;
  58
  59         return 0;
  60 }
  61
  62 int bus_unit_append_following(DBusMessageIter *i, const char *property, void *data) {
  63         Unit *u = data, *f;
  64         const char *d;
  65
  66         assert(i);
  67         assert(property);
  68         assert(u);
  69
  70         f = unit_following(u);
  71         d = f ? f->meta.id : "";
  72
  73         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &d))
  74                 return -ENOMEM;
  75
  76         return 0;
  77 }
  78
  79 int bus_unit_append_dependencies(DBusMessageIter *i, const char *property, void *data) {
  80         Unit *u;
  81         Iterator j;
  82         DBusMessageIter sub;
  83         Set *s = data;
  84
  85         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
  86                 return -ENOMEM;
  87
  88         SET_FOREACH(u, s, j)
  89                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &u->meta.id))
  90                         return -ENOMEM;
  91
  92         if (!dbus_message_iter_close_container(i, &sub))
  93                 return -ENOMEM;
  94
  95         return 0;
  96 }
  97
  98 int bus_unit_append_description(DBusMessageIter *i, const char *property, void *data) {
  99         Unit *u = data;
 100         const char *d;
 101
 102         assert(i);
 103         assert(property);
 104         assert(u);
 105
 106         d = unit_description(u);
 107
 108         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &d))
 109                 return -ENOMEM;
 110
 111         return 0;
 112 }
 113
 114 DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_unit_append_load_state, unit_load_state, UnitLoadState);
 115
 116 int bus_unit_append_active_state(DBusMessageIter *i, const char *property, void *data) {
 117         Unit *u = data;
 118         const char *state;
 119
 120         assert(i);
 121         assert(property);
 122         assert(u);
 123
 124         state = unit_active_state_to_string(unit_active_state(u));
 125
 126         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &state))
 127                 return -ENOMEM;
 128
 129         return 0;
 130 }
 131
 132 int bus_unit_append_sub_state(DBusMessageIter *i, const char *property, void *data) {
 133         Unit *u = data;
 134         const char *state;
 135
 136         assert(i);
 137         assert(property);
 138         assert(u);
 139
 140         state = unit_sub_state_to_string(u);
 141
 142         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &state))
 143                 return -ENOMEM;
 144
 145         return 0;
 146 }
 147
 148 int bus_unit_append_can_start(DBusMessageIter *i, const char *property, void *data) {
 149         Unit *u = data;
 150         dbus_bool_t b;
 151
 152         assert(i);
 153         assert(property);
 154         assert(u);
 155
 156         b = unit_can_start(u) &&
 157                 !u->meta.refuse_manual_start;
 158
 159         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 160                 return -ENOMEM;
 161
 162         return 0;
 163 }
 164
 165 int bus_unit_append_can_stop(DBusMessageIter *i, const char *property, void *data) {
 166         Unit *u = data;
 167         dbus_bool_t b;
 168
 169         assert(i);
 170         assert(property);
 171         assert(u);
 172
 173         /* On the lower levels we assume that every unit we can start
 174          * we can also stop */
 175
 176         b = unit_can_start(u) &&
 177                 !u->meta.refuse_manual_stop;
 178
 179         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 180                 return -ENOMEM;
 181
 182         return 0;
 183 }
 184
 185 int bus_unit_append_can_reload(DBusMessageIter *i, const char *property, void *data) {
 186         Unit *u = data;
 187         dbus_bool_t b;
 188
 189         assert(i);
 190         assert(property);
 191         assert(u);
 192
 193         b = unit_can_reload(u);
 194
 195         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 196                 return -ENOMEM;
 197
 198         return 0;
 199 }
 200
 201 int bus_unit_append_can_isolate(DBusMessageIter *i, const char *property, void *data) {
 202         Unit *u = data;
 203         dbus_bool_t b;
 204
 205         assert(i);
 206         assert(property);
 207         assert(u);
 208
 209         b = unit_can_isolate(u) &&
 210                 !u->meta.refuse_manual_start;
 211
 212         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 213                 return -ENOMEM;
 214
 215         return 0;
 216 }
 217
 218 int bus_unit_append_job(DBusMessageIter *i, const char *property, void *data) {
 219         Unit *u = data;
 220         DBusMessageIter sub;
 221         char *p;
 222
 223         assert(i);
 224         assert(property);
 225         assert(u);
 226
 227         if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub))
 228                 return -ENOMEM;
 229
 230         if (u->meta.job) {
 231
 232                 if (!(p = job_dbus_path(u->meta.job)))
 233                         return -ENOMEM;
 234
 235                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_UINT32, &u->meta.job->id) ||
 236                     !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &p)) {
 237                         free(p);
 238                         return -ENOMEM;
 239                 }
 240         } else {
 241                 uint32_t id = 0;
 242
 243                 /* No job, so let's fill in some placeholder
 244                  * data. Since we need to fill in a valid path we
 245                  * simple point to ourselves. */
 246
 247                 if (!(p = unit_dbus_path(u)))
 248                         return -ENOMEM;
 249
 250                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_UINT32, &id) ||
 251                     !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &p)) {
 252                         free(p);
 253                         return -ENOMEM;
 254                 }
 255         }
 256
 257         free(p);
 258
 259         if (!dbus_message_iter_close_container(i, &sub))
 260                 return -ENOMEM;
 261
 262         return 0;
 263 }
 264
 265 int bus_unit_append_default_cgroup(DBusMessageIter *i, const char *property, void *data) {
 266         Unit *u = data;
 267         char *t;
 268         CGroupBonding *cgb;
 269         bool success;
 270
 271         assert(i);
 272         assert(property);
 273         assert(u);
 274
 275         if ((cgb = unit_get_default_cgroup(u))) {
 276                 if (!(t = cgroup_bonding_to_string(cgb)))
 277                         return -ENOMEM;
 278         } else
 279                 t = (char*) "";
 280
 281         success = dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &t);
 282
 283         if (cgb)
 284                 free(t);
 285
 286         return success ? 0 : -ENOMEM;
 287 }
 288
 289 int bus_unit_append_cgroups(DBusMessageIter *i, const char *property, void *data) {
 290         Unit *u = data;
 291         CGroupBonding *cgb;
 292         DBusMessageIter sub;
 293
 294         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
 295                 return -ENOMEM;
 296
 297         LIST_FOREACH(by_unit, cgb, u->meta.cgroup_bondings) {
 298                 char *t;
 299                 bool success;
 300
 301                 if (!(t = cgroup_bonding_to_string(cgb)))
 302                         return -ENOMEM;
 303
 304                 success = dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &t);
 305                 free(t);
 306
 307                 if (!success)
 308                         return -ENOMEM;
 309         }
 310
 311         if (!dbus_message_iter_close_container(i, &sub))
 312                 return -ENOMEM;
 313
 314         return 0;
 315 }
 316
 317 int bus_unit_append_need_daemon_reload(DBusMessageIter *i, const char *property, void *data) {
 318         Unit *u = data;
 319         dbus_bool_t b;
 320
 321         assert(i);
 322         assert(property);
 323         assert(u);
 324
 325         b = unit_need_daemon_reload(u);
 326
 327         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 328                 return -ENOMEM;
 329
 330         return 0;
 331 }
 332
 333 int bus_unit_append_load_error(DBusMessageIter *i, const char *property, void *data) {
 334         Unit *u = data;
 335         const char *name, *message;
 336         DBusMessageIter sub;
 337
 338         assert(i);
 339         assert(property);
 340         assert(u);
 341
 342         if (u->meta.load_error != 0) {
 343                 name = bus_errno_to_dbus(u->meta.load_error);
 344                 message = strempty(strerror(-u->meta.load_error));
 345         } else
 346                 name = message = "";
 347
 348         if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub) ||
 349             !dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &name) ||
 350             !dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &message) ||
 351             !dbus_message_iter_close_container(i, &sub))
 352                 return -ENOMEM;
 353
 354         return 0;
 355 }
 356
 357 static DBusHandlerResult bus_unit_message_dispatch(Unit *u, DBusConnection *connection, DBusMessage *message) {
 358         DBusMessage *reply = NULL;
 359         Manager *m = u->meta.manager;
 360         DBusError error;
 361         JobType job_type = _JOB_TYPE_INVALID;
 362         char *path = NULL;
 363         bool reload_if_possible = false;
 364
 365         dbus_error_init(&error);
 366
 367         if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Start"))
 368                 job_type = JOB_START;
 369         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Stop"))
 370                 job_type = JOB_STOP;
 371         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Reload"))
 372                 job_type = JOB_RELOAD;
 373         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Restart"))
 374                 job_type = JOB_RESTART;
 375         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "TryRestart"))
 376                 job_type = JOB_TRY_RESTART;
 377         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ReloadOrRestart")) {
 378                 reload_if_possible = true;
 379                 job_type = JOB_RESTART;
 380         } else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ReloadOrTryRestart")) {
 381                 reload_if_possible = true;
 382                 job_type = JOB_TRY_RESTART;
 383         } else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Kill")) {
 384                 const char *swho, *smode;
 385                 int32_t signo;
 386                 KillMode mode;
 387                 KillWho who;
 388                 int r;
 389
 390                 if (!dbus_message_get_args(
 391                                     message,
 392                                     &error,
 393                                     DBUS_TYPE_STRING, &swho,
 394                                     DBUS_TYPE_STRING, &smode,
 395                                     DBUS_TYPE_INT32, &signo,
 396                                     DBUS_TYPE_INVALID))
 397                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 398
 399                 if (isempty(swho))
 400                         who = KILL_ALL;
 401                 else {
 402                         who = kill_who_from_string(swho);
 403                         if (who < 0)
 404                                 return bus_send_error_reply(connection, message, &error, -EINVAL);
 405                 }
 406
 407                 if (isempty(smode))
 408                         mode = KILL_CONTROL_GROUP;
 409                 else {
 410                         mode = kill_mode_from_string(smode);
 411                         if (mode < 0)
 412                                 return bus_send_error_reply(connection, message, &error, -EINVAL);
 413                 }
 414
 415                 if (signo <= 0 || signo >= _NSIG)
 416                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 417
 418                 if ((r = unit_kill(u, who, mode, signo, &error)) < 0)
 419                         return bus_send_error_reply(connection, message, &error, r);
 420
 421                 if (!(reply = dbus_message_new_method_return(message)))
 422                         goto oom;
 423
 424         } else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ResetFailed")) {
 425
 426                 unit_reset_failed(u);
 427
 428                 if (!(reply = dbus_message_new_method_return(message)))
 429                         goto oom;
 430
 431         } else if (UNIT_VTABLE(u)->bus_message_handler)
 432                 return UNIT_VTABLE(u)->bus_message_handler(u, connection, message);
 433         else
 434                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 435
 436         if (job_type != _JOB_TYPE_INVALID) {
 437                 const char *smode;
 438                 JobMode mode;
 439                 Job *j;
 440                 int r;
 441
 442                 if ((job_type == JOB_START && u->meta.refuse_manual_start) ||
 443                     (job_type == JOB_STOP && u->meta.refuse_manual_stop) ||
 444                     ((job_type == JOB_RESTART || job_type == JOB_TRY_RESTART) &&
 445                      (u->meta.refuse_manual_start || u->meta.refuse_manual_stop))) {
 446                         dbus_set_error(&error, BUS_ERROR_ONLY_BY_DEPENDENCY, "Operation refused, may be requested by dependency only.");
 447                         return bus_send_error_reply(connection, message, &error, -EPERM);
 448                 }
 449
 450                 if (!dbus_message_get_args(
 451                                     message,
 452                                     &error,
 453                                     DBUS_TYPE_STRING, &smode,
 454                                     DBUS_TYPE_INVALID))
 455                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 456
 457                 if (reload_if_possible && unit_can_reload(u)) {
 458                         if (job_type == JOB_RESTART)
 459                                 job_type = JOB_RELOAD_OR_START;
 460                         else if (job_type == JOB_TRY_RESTART)
 461                                 job_type = JOB_RELOAD;
 462                 }
 463
 464                 if ((mode = job_mode_from_string(smode)) == _JOB_MODE_INVALID) {
 465                         dbus_set_error(&error, BUS_ERROR_INVALID_JOB_MODE, "Job mode %s is invalid.", smode);
 466                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 467                 }
 468
 469                 if ((r = manager_add_job(m, job_type, u, mode, true, &error, &j)) < 0)
 470                         return bus_send_error_reply(connection, message, &error, r);
 471
 472                 if (!(reply = dbus_message_new_method_return(message)))
 473                         goto oom;
 474
 475                 if (!(path = job_dbus_path(j)))
 476                         goto oom;
 477
 478                 if (!dbus_message_append_args(
 479                                     reply,
 480                                     DBUS_TYPE_OBJECT_PATH, &path,
 481                                     DBUS_TYPE_INVALID))
 482                         goto oom;
 483         }
 484
 485         if (reply) {
 486                 if (!dbus_connection_send(connection, reply, NULL))
 487                         goto oom;
 488
 489                 dbus_message_unref(reply);
 490         }
 491
 492         free(path);
 493
 494         return DBUS_HANDLER_RESULT_HANDLED;
 495
 496 oom:
 497         free(path);
 498
 499         if (reply)
 500                 dbus_message_unref(reply);
 501
 502         dbus_error_free(&error);
 503
 504         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 505 }
 506
 507 static DBusHandlerResult bus_unit_message_handler(DBusConnection *connection, DBusMessage  *message, void *data) {
 508         Manager *m = data;
 509         Unit *u;
 510         int r;
 511         DBusMessage *reply;
 512
 513         assert(connection);
 514         assert(message);
 515         assert(m);
 516
 517         if (streq(dbus_message_get_path(message), "/org/freedesktop/systemd1/unit")) {
 518                 /* Be nice to gdbus and return introspection data for our mid-level paths */
 519
 520                 if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Introspectable", "Introspect")) {
 521                         char *introspection = NULL;
 522                         FILE *f;
 523                         Iterator i;
 524                         const char *k;
 525                         size_t size;
 526
 527                         if (!(reply = dbus_message_new_method_return(message)))
 528                                 goto oom;
 529
 530                         /* We roll our own introspection code here, instead of
 531                          * relying on bus_default_message_handler() because we
 532                          * need to generate our introspection string
 533                          * dynamically. */
 534
 535                         if (!(f = open_memstream(&introspection, &size)))
 536                                 goto oom;
 537
 538                         fputs(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE
 539                               "<node>\n", f);
 540
 541                         fputs(BUS_INTROSPECTABLE_INTERFACE, f);
 542                         fputs(BUS_PEER_INTERFACE, f);
 543
 544                         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
 545                                 char *p;
 546
 547                                 if (k != u->meta.id)
 548                                         continue;
 549
 550                                 if (!(p = bus_path_escape(k))) {
 551                                         fclose(f);
 552                                         free(introspection);
 553                                         goto oom;
 554                                 }
 555
 556                                 fprintf(f, "<node name=\"%s\"/>", p);
 557                                 free(p);
 558                         }
 559
 560                         fputs("</node>\n", f);
 561
 562                         if (ferror(f)) {
 563                                 fclose(f);
 564                                 free(introspection);
 565                                 goto oom;
 566                         }
 567
 568                         fclose(f);
 569
 570                         if (!introspection)
 571                                 goto oom;
 572
 573                         if (!dbus_message_append_args(reply, DBUS_TYPE_STRING, &introspection, DBUS_TYPE_INVALID)) {
 574                                 free(introspection);
 575                                 goto oom;
 576                         }
 577
 578                         free(introspection);
 579
 580                         if (!dbus_connection_send(connection, reply, NULL))
 581                                 goto oom;
 582
 583                         dbus_message_unref(reply);
 584
 585                         return DBUS_HANDLER_RESULT_HANDLED;
 586                 }
 587
 588                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 589         }
 590
 591         if ((r = manager_get_unit_from_dbus_path(m, dbus_message_get_path(message), &u)) < 0) {
 592
 593                 if (r == -ENOMEM)
 594                         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 595
 596                 if (r == -ENOENT) {
 597                         DBusError e;
 598
 599                         dbus_error_init(&e);
 600                         dbus_set_error_const(&e, DBUS_ERROR_UNKNOWN_OBJECT, "Unknown unit");
 601                         return bus_send_error_reply(connection, message, &e, r);
 602                 }
 603
 604                 return bus_send_error_reply(connection, message, NULL, r);
 605         }
 606
 607         return bus_unit_message_dispatch(u, connection, message);
 608
 609 oom:
 610         if (reply)
 611                 dbus_message_unref(reply);
 612
 613         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 614 }
 615
 616 const DBusObjectPathVTable bus_unit_vtable = {
 617         .message_function = bus_unit_message_handler
 618 };
 619
 620 void bus_unit_send_change_signal(Unit *u) {
 621         char *p = NULL;
 622         DBusMessage *m = NULL;
 623
 624         assert(u);
 625
 626         if (u->meta.in_dbus_queue) {
 627                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 628                 u->meta.in_dbus_queue = false;
 629         }
 630
 631         if (!u->meta.id)
 632                 return;
 633
 634         if (!bus_has_subscriber(u->meta.manager)) {
 635                 u->meta.sent_dbus_new_signal = true;
 636                 return;
 637         }
 638
 639         if (!(p = unit_dbus_path(u)))
 640                 goto oom;
 641
 642         if (u->meta.sent_dbus_new_signal) {
 643                 /* Send a properties changed signal. First for the
 644                  * specific type, then for the generic unit. The
 645                  * clients may rely on this order to get atomic
 646                  * behaviour if needed. */
 647
 648                 if (UNIT_VTABLE(u)->bus_invalidating_properties) {
 649
 650                         if (!(m = bus_properties_changed_new(p,
 651                                                              UNIT_VTABLE(u)->bus_interface,
 652                                                              UNIT_VTABLE(u)->bus_invalidating_properties)))
 653                                 goto oom;
 654
 655                         if (bus_broadcast(u->meta.manager, m) < 0)
 656                                 goto oom;
 657
 658                         dbus_message_unref(m);
 659                 }
 660
 661                 if (!(m = bus_properties_changed_new(p, "org.freedesktop.systemd1.Unit", INVALIDATING_PROPERTIES)))
 662                         goto oom;
 663
 664         } else {
 665                 /* Send a new signal */
 666
 667                 if (!(m = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "UnitNew")))
 668                         goto oom;
 669
 670                 if (!dbus_message_append_args(m,
 671                                               DBUS_TYPE_STRING, &u->meta.id,
 672                                               DBUS_TYPE_OBJECT_PATH, &p,
 673                                               DBUS_TYPE_INVALID))
 674                         goto oom;
 675         }
 676
 677         if (bus_broadcast(u->meta.manager, m) < 0)
 678                 goto oom;
 679
 680         free(p);
 681         dbus_message_unref(m);
 682
 683         u->meta.sent_dbus_new_signal = true;
 684
 685         return;
 686
 687 oom:
 688         free(p);
 689
 690         if (m)
 691                 dbus_message_unref(m);
 692
 693         log_error("Failed to allocate unit change/new signal.");
 694 }
 695
 696 void bus_unit_send_removed_signal(Unit *u) {
 697         char *p = NULL;
 698         DBusMessage *m = NULL;
 699
 700         assert(u);
 701
 702         if (!bus_has_subscriber(u->meta.manager))
 703                 return;
 704
 705         if (!u->meta.sent_dbus_new_signal)
 706                 bus_unit_send_change_signal(u);
 707
 708         if (!u->meta.id)
 709                 return;
 710
 711         if (!(p = unit_dbus_path(u)))
 712                 goto oom;
 713
 714         if (!(m = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "UnitRemoved")))
 715                 goto oom;
 716
 717         if (!dbus_message_append_args(m,
 718                                       DBUS_TYPE_STRING, &u->meta.id,
 719                                       DBUS_TYPE_OBJECT_PATH, &p,
 720                                       DBUS_TYPE_INVALID))
 721                 goto oom;
 722
 723         if (bus_broadcast(u->meta.manager, m) < 0)
 724                 goto oom;
 725
 726         free(p);
 727         dbus_message_unref(m);
 728
 729         return;
 730
 731 oom:
 732         free(p);
 733
 734         if (m)
 735                 dbus_message_unref(m);
 736
 737         log_error("Failed to allocate unit remove signal.");
 738 }