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
  29 const char bus_unit_interface[] = BUS_UNIT_INTERFACE;
  30
  31 #define INVALIDATING_PROPERTIES                 \
  32         "LoadState\0"                           \
  33         "ActiveState\0"                         \
  34         "SubState\0"                            \
  35         "InactiveExitTimestamp\0"               \
  36         "ActiveEnterTimestamp\0"                \
  37         "ActiveExitTimestamp\0"                 \
  38         "InactiveEnterTimestamp\0"              \
  39         "Job\0"                                 \
  40         "NeedDaemonReload\0"                    \
  41         "\0"
  42
  43 int bus_unit_append_names(Manager *m, 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(Manager *m, DBusMessageIter *i, const char *property, void *data) {
  63         Unit *u = data, *f;
  64         const char *d;
  65
  66         assert(m);
  67         assert(i);
  68         assert(property);
  69         assert(u);
  70
  71         f = unit_following(u);
  72         d = f ? f->meta.id : "";
  73
  74         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &d))
  75                 return -ENOMEM;
  76
  77         return 0;
  78 }
  79
  80 int bus_unit_append_dependencies(Manager *m, DBusMessageIter *i, const char *property, void *data) {
  81         Unit *u;
  82         Iterator j;
  83         DBusMessageIter sub;
  84         Set *s = data;
  85
  86         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
  87                 return -ENOMEM;
  88
  89         SET_FOREACH(u, s, j)
  90                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &u->meta.id))
  91                         return -ENOMEM;
  92
  93         if (!dbus_message_iter_close_container(i, &sub))
  94                 return -ENOMEM;
  95
  96         return 0;
  97 }
  98
  99 int bus_unit_append_description(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 100         Unit *u = data;
 101         const char *d;
 102
 103         assert(m);
 104         assert(i);
 105         assert(property);
 106         assert(u);
 107
 108         d = unit_description(u);
 109
 110         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &d))
 111                 return -ENOMEM;
 112
 113         return 0;
 114 }
 115
 116 DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_unit_append_load_state, unit_load_state, UnitLoadState);
 117
 118 int bus_unit_append_active_state(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 119         Unit *u = data;
 120         const char *state;
 121
 122         assert(m);
 123         assert(i);
 124         assert(property);
 125         assert(u);
 126
 127         state = unit_active_state_to_string(unit_active_state(u));
 128
 129         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &state))
 130                 return -ENOMEM;
 131
 132         return 0;
 133 }
 134
 135 int bus_unit_append_sub_state(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 136         Unit *u = data;
 137         const char *state;
 138
 139         assert(m);
 140         assert(i);
 141         assert(property);
 142         assert(u);
 143
 144         state = unit_sub_state_to_string(u);
 145
 146         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &state))
 147                 return -ENOMEM;
 148
 149         return 0;
 150 }
 151
 152 int bus_unit_append_can_start(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 153         Unit *u = data;
 154         dbus_bool_t b;
 155
 156         assert(m);
 157         assert(i);
 158         assert(property);
 159         assert(u);
 160
 161         b = unit_can_start(u) &&
 162                 !u->meta.refuse_manual_start;
 163
 164         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 165                 return -ENOMEM;
 166
 167         return 0;
 168 }
 169
 170 int bus_unit_append_can_stop(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 171         Unit *u = data;
 172         dbus_bool_t b;
 173
 174         assert(m);
 175         assert(i);
 176         assert(property);
 177         assert(u);
 178
 179         /* On the lower levels we assume that every unit we can start
 180          * we can also stop */
 181
 182         b = unit_can_start(u) &&
 183                 !u->meta.refuse_manual_stop;
 184
 185         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 186                 return -ENOMEM;
 187
 188         return 0;
 189 }
 190
 191 int bus_unit_append_can_reload(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 192         Unit *u = data;
 193         dbus_bool_t b;
 194
 195         assert(m);
 196         assert(i);
 197         assert(property);
 198         assert(u);
 199
 200         b = unit_can_reload(u);
 201
 202         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 203                 return -ENOMEM;
 204
 205         return 0;
 206 }
 207
 208 int bus_unit_append_job(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 209         Unit *u = data;
 210         DBusMessageIter sub;
 211         char *p;
 212
 213         assert(m);
 214         assert(i);
 215         assert(property);
 216         assert(u);
 217
 218         if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub))
 219                 return -ENOMEM;
 220
 221         if (u->meta.job) {
 222
 223                 if (!(p = job_dbus_path(u->meta.job)))
 224                         return -ENOMEM;
 225
 226                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_UINT32, &u->meta.job->id) ||
 227                     !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &p)) {
 228                         free(p);
 229                         return -ENOMEM;
 230                 }
 231         } else {
 232                 uint32_t id = 0;
 233
 234                 /* No job, so let's fill in some placeholder
 235                  * data. Since we need to fill in a valid path we
 236                  * simple point to ourselves. */
 237
 238                 if (!(p = unit_dbus_path(u)))
 239                         return -ENOMEM;
 240
 241                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_UINT32, &id) ||
 242                     !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &p)) {
 243                         free(p);
 244                         return -ENOMEM;
 245                 }
 246         }
 247
 248         free(p);
 249
 250         if (!dbus_message_iter_close_container(i, &sub))
 251                 return -ENOMEM;
 252
 253         return 0;
 254 }
 255
 256 int bus_unit_append_default_cgroup(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 257         Unit *u = data;
 258         char *t;
 259         CGroupBonding *cgb;
 260         bool success;
 261
 262         assert(m);
 263         assert(i);
 264         assert(property);
 265         assert(u);
 266
 267         if ((cgb = unit_get_default_cgroup(u))) {
 268                 if (!(t = cgroup_bonding_to_string(cgb)))
 269                         return -ENOMEM;
 270         } else
 271                 t = (char*) "";
 272
 273         success = dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &t);
 274
 275         if (cgb)
 276                 free(t);
 277
 278         return success ? 0 : -ENOMEM;
 279 }
 280
 281 int bus_unit_append_cgroups(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 282         Unit *u = data;
 283         CGroupBonding *cgb;
 284         DBusMessageIter sub;
 285
 286         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
 287                 return -ENOMEM;
 288
 289         LIST_FOREACH(by_unit, cgb, u->meta.cgroup_bondings) {
 290                 char *t;
 291                 bool success;
 292
 293                 if (!(t = cgroup_bonding_to_string(cgb)))
 294                         return -ENOMEM;
 295
 296                 success = dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &t);
 297                 free(t);
 298
 299                 if (!success)
 300                         return -ENOMEM;
 301         }
 302
 303         if (!dbus_message_iter_close_container(i, &sub))
 304                 return -ENOMEM;
 305
 306         return 0;
 307 }
 308
 309 int bus_unit_append_need_daemon_reload(Manager *m, DBusMessageIter *i, const char *property, void *data) {
 310         Unit *u = data;
 311         dbus_bool_t b;
 312
 313         assert(m);
 314         assert(i);
 315         assert(property);
 316         assert(u);
 317
 318         b = unit_need_daemon_reload(u);
 319
 320         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 321                 return -ENOMEM;
 322
 323         return 0;
 324 }
 325
 326 static DBusHandlerResult bus_unit_message_dispatch(Unit *u, DBusConnection *connection, DBusMessage *message) {
 327         DBusMessage *reply = NULL;
 328         Manager *m = u->meta.manager;
 329         DBusError error;
 330         JobType job_type = _JOB_TYPE_INVALID;
 331         char *path = NULL;
 332         bool reload_if_possible = false;
 333
 334         dbus_error_init(&error);
 335
 336         if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Start"))
 337                 job_type = JOB_START;
 338         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Stop"))
 339                 job_type = JOB_STOP;
 340         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Reload"))
 341                 job_type = JOB_RELOAD;
 342         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "Restart"))
 343                 job_type = JOB_RESTART;
 344         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "TryRestart"))
 345                 job_type = JOB_TRY_RESTART;
 346         else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ReloadOrRestart")) {
 347                 reload_if_possible = true;
 348                 job_type = JOB_RESTART;
 349         } else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ReloadOrTryRestart")) {
 350                 reload_if_possible = true;
 351                 job_type = JOB_TRY_RESTART;
 352         } else if (dbus_message_is_method_call(message, "org.freedesktop.systemd1.Unit", "ResetMaintenance")) {
 353
 354                 unit_reset_maintenance(u);
 355
 356                 if (!(reply = dbus_message_new_method_return(message)))
 357                         goto oom;
 358
 359         } else if (UNIT_VTABLE(u)->bus_message_handler)
 360                 return UNIT_VTABLE(u)->bus_message_handler(u, connection, message);
 361         else
 362                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 363
 364         if (job_type != _JOB_TYPE_INVALID) {
 365                 const char *smode;
 366                 JobMode mode;
 367                 Job *j;
 368                 int r;
 369
 370                 if ((job_type == JOB_START && u->meta.refuse_manual_start) ||
 371                     (job_type == JOB_STOP && u->meta.refuse_manual_stop) ||
 372                     ((job_type == JOB_RESTART || job_type == JOB_TRY_RESTART) &&
 373                      (u->meta.refuse_manual_start || u->meta.refuse_manual_stop))) {
 374                         dbus_set_error(&error, BUS_ERROR_ONLY_BY_DEPENDENCY, "Operation refused, may be requested by dependency only.");
 375                         return bus_send_error_reply(m, connection, message, &error, -EPERM);
 376                 }
 377
 378                 if (!dbus_message_get_args(
 379                                     message,
 380                                     &error,
 381                                     DBUS_TYPE_STRING, &smode,
 382                                     DBUS_TYPE_INVALID))
 383                         return bus_send_error_reply(m, connection, message, &error, -EINVAL);
 384
 385                 if (reload_if_possible && unit_can_reload(u)) {
 386                         if (job_type == JOB_RESTART)
 387                                 job_type = JOB_RELOAD_OR_START;
 388                         else if (job_type == JOB_TRY_RESTART)
 389                                 job_type = JOB_RELOAD;
 390                 }
 391
 392                 if ((mode = job_mode_from_string(smode)) == _JOB_MODE_INVALID) {
 393                         dbus_set_error(&error, BUS_ERROR_INVALID_JOB_MODE, "Job mode %s is invalid.", smode);
 394                         return bus_send_error_reply(m, connection, message, &error, -EINVAL);
 395                 }
 396
 397                 if ((r = manager_add_job(m, job_type, u, mode, true, &error, &j)) < 0)
 398                         return bus_send_error_reply(m, connection, message, &error, r);
 399
 400                 if (!(reply = dbus_message_new_method_return(message)))
 401                         goto oom;
 402
 403                 if (!(path = job_dbus_path(j)))
 404                         goto oom;
 405
 406                 if (!dbus_message_append_args(
 407                                     reply,
 408                                     DBUS_TYPE_OBJECT_PATH, &path,
 409                                     DBUS_TYPE_INVALID))
 410                         goto oom;
 411         }
 412
 413         free(path);
 414
 415         if (reply) {
 416                 if (!dbus_connection_send(connection, reply, NULL))
 417                         goto oom;
 418
 419                 dbus_message_unref(reply);
 420         }
 421
 422         return DBUS_HANDLER_RESULT_HANDLED;
 423
 424 oom:
 425         free(path);
 426
 427         if (reply)
 428                 dbus_message_unref(reply);
 429
 430         dbus_error_free(&error);
 431
 432         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 433 }
 434
 435 static DBusHandlerResult bus_unit_message_handler(DBusConnection *connection, DBusMessage  *message, void *data) {
 436         Manager *m = data;
 437         Unit *u;
 438         int r;
 439
 440         assert(connection);
 441         assert(message);
 442         assert(m);
 443
 444         if ((r = manager_get_unit_from_dbus_path(m, dbus_message_get_path(message), &u)) < 0) {
 445
 446                 if (r == -ENOMEM)
 447                         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 448
 449                 if (r == -ENOENT)
 450                         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 451
 452                 return bus_send_error_reply(m, connection, message, NULL, r);
 453         }
 454
 455         return bus_unit_message_dispatch(u, connection, message);
 456 }
 457
 458 const DBusObjectPathVTable bus_unit_vtable = {
 459         .message_function = bus_unit_message_handler
 460 };
 461
 462 void bus_unit_send_change_signal(Unit *u) {
 463         char *p = NULL;
 464         DBusMessage *m = NULL;
 465
 466         assert(u);
 467
 468         if (u->meta.in_dbus_queue) {
 469                 LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
 470                 u->meta.in_dbus_queue = false;
 471         }
 472
 473         if (!u->meta.id)
 474                 return;
 475
 476         if (!bus_has_subscriber(u->meta.manager)) {
 477                 u->meta.sent_dbus_new_signal = true;
 478                 return;
 479         }
 480
 481         if (!(p = unit_dbus_path(u)))
 482                 goto oom;
 483
 484         if (u->meta.sent_dbus_new_signal) {
 485                 /* Send a properties changed signal. First for the
 486                  * specific type, then for the generic unit. The
 487                  * clients may rely on this order to get atomic
 488                  * behaviour if needed. */
 489
 490                 if (UNIT_VTABLE(u)->bus_invalidating_properties) {
 491
 492                         if (!(m = bus_properties_changed_new(p,
 493                                                              UNIT_VTABLE(u)->bus_interface,
 494                                                              UNIT_VTABLE(u)->bus_invalidating_properties)))
 495                                 goto oom;
 496
 497                         if (bus_broadcast(u->meta.manager, m) < 0)
 498                                 goto oom;
 499
 500                         dbus_message_unref(m);
 501                 }
 502
 503                 if (!(m = bus_properties_changed_new(p, "org.freedesktop.systemd1.Unit", INVALIDATING_PROPERTIES)))
 504                         goto oom;
 505
 506         } else {
 507                 /* Send a new signal */
 508
 509                 if (!(m = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "UnitNew")))
 510                         goto oom;
 511
 512                 if (!dbus_message_append_args(m,
 513                                               DBUS_TYPE_STRING, &u->meta.id,
 514                                               DBUS_TYPE_OBJECT_PATH, &p,
 515                                               DBUS_TYPE_INVALID))
 516                         goto oom;
 517         }
 518
 519         if (bus_broadcast(u->meta.manager, m) < 0)
 520                 goto oom;
 521
 522         free(p);
 523         dbus_message_unref(m);
 524
 525         u->meta.sent_dbus_new_signal = true;
 526
 527         return;
 528
 529 oom:
 530         free(p);
 531
 532         if (m)
 533                 dbus_message_unref(m);
 534
 535         log_error("Failed to allocate unit change/new signal.");
 536 }
 537
 538 void bus_unit_send_removed_signal(Unit *u) {
 539         char *p = NULL;
 540         DBusMessage *m = NULL;
 541
 542         assert(u);
 543
 544         if (!bus_has_subscriber(u->meta.manager))
 545                 return;
 546
 547         if (!u->meta.sent_dbus_new_signal)
 548                 bus_unit_send_change_signal(u);
 549
 550         if (!u->meta.id)
 551                 return;
 552
 553         if (!(p = unit_dbus_path(u)))
 554                 goto oom;
 555
 556         if (!(m = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "UnitRemoved")))
 557                 goto oom;
 558
 559         if (!dbus_message_append_args(m,
 560                                       DBUS_TYPE_STRING, &u->meta.id,
 561                                       DBUS_TYPE_OBJECT_PATH, &p,
 562                                       DBUS_TYPE_INVALID))
 563                 goto oom;
 564
 565         if (bus_broadcast(u->meta.manager, m) < 0)
 566                 goto oom;
 567
 568         free(p);
 569         dbus_message_unref(m);
 570
 571         return;
 572
 573 oom:
 574         free(p);
 575
 576         if (m)
 577                 dbus_message_unref(m);
 578
 579         log_error("Failed to allocate unit remove signal.");
 580 }