gio/gunionvolumemonitor.c

   1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
   2
   3 /* GIO - GLib Input, Output and Streaming Library
   4  *
   5  * Copyright (C) 2006-2007 Red Hat, Inc.
   6  *
   7  * SPDX-License-Identifier: LGPL-2.1-or-later
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General
  20  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  21  *
  22  * Author: Alexander Larsson <alexl@redhat.com>
  23  *         David Zeuthen <davidz@redhat.com>
  24  */
  25
  26 #include "config.h"
  27
  28 #include <string.h>
  29
  30 #include <glib.h>
  31 #include "gunionvolumemonitor.h"
  32 #include "gmountprivate.h"
  33 #include "giomodule-priv.h"
  34 #ifdef G_OS_UNIX
  35 #include "gunixvolumemonitor.h"
  36 #endif
  37 #include "gnativevolumemonitor.h"
  38
  39 #include "glibintl.h"
  40
  41
  42 struct _GUnionVolumeMonitor {
  43   GVolumeMonitor parent;
  44
  45   GList *monitors;
  46 };
  47
  48 static void g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,
  49                                                    GVolumeMonitor *child_monitor);
  50
  51
  52 #define g_union_volume_monitor_get_type _g_union_volume_monitor_get_type
  53 G_DEFINE_TYPE (GUnionVolumeMonitor, g_union_volume_monitor, G_TYPE_VOLUME_MONITOR)
  54
  55 static GRecMutex the_volume_monitor_mutex;
  56
  57 static GUnionVolumeMonitor *the_volume_monitor = NULL;
  58
  59 static void
  60 g_union_volume_monitor_finalize (GObject *object)
  61 {
  62   GUnionVolumeMonitor *monitor;
  63   GVolumeMonitor *child_monitor;
  64
  65   monitor = G_UNION_VOLUME_MONITOR (object);
  66
  67   while (monitor->monitors != NULL)
  68     {
  69       child_monitor = monitor->monitors->data;
  70       g_union_volume_monitor_remove_monitor (monitor,
  71                                              child_monitor);
  72       g_object_unref (child_monitor);
  73     }
  74
  75   G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->finalize (object);
  76 }
  77
  78 static void
  79 g_union_volume_monitor_dispose (GObject *object)
  80 {
  81   GUnionVolumeMonitor *monitor;
  82   GVolumeMonitor *child_monitor;
  83   GList *l;
  84
  85   monitor = G_UNION_VOLUME_MONITOR (object);
  86
  87   g_rec_mutex_lock (&the_volume_monitor_mutex);
  88   the_volume_monitor = NULL;
  89
  90   for (l = monitor->monitors; l != NULL; l = l->next)
  91     {
  92       child_monitor = l->data;
  93       g_object_run_dispose (G_OBJECT (child_monitor));
  94     }
  95
  96   g_rec_mutex_unlock (&the_volume_monitor_mutex);
  97
  98   G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->dispose (object);
  99 }
 100
 101 static GList *
 102 get_mounts (GVolumeMonitor *volume_monitor)
 103 {
 104   GUnionVolumeMonitor *monitor;
 105   GVolumeMonitor *child_monitor;
 106   GList *res;
 107   GList *l;
 108
 109   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 110
 111   res = NULL;
 112
 113   g_rec_mutex_lock (&the_volume_monitor_mutex);
 114
 115   for (l = monitor->monitors; l != NULL; l = l->next)
 116     {
 117       child_monitor = l->data;
 118
 119       res = g_list_concat (res, g_volume_monitor_get_mounts (child_monitor));
 120     }
 121
 122   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 123
 124   return res;
 125 }
 126
 127 static GList *
 128 get_volumes (GVolumeMonitor *volume_monitor)
 129 {
 130   GUnionVolumeMonitor *monitor;
 131   GVolumeMonitor *child_monitor;
 132   GList *res;
 133   GList *l;
 134
 135   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 136
 137   res = NULL;
 138
 139   g_rec_mutex_lock (&the_volume_monitor_mutex);
 140
 141   for (l = monitor->monitors; l != NULL; l = l->next)
 142     {
 143       child_monitor = l->data;
 144
 145       res = g_list_concat (res, g_volume_monitor_get_volumes (child_monitor));
 146     }
 147
 148   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 149
 150   return res;
 151 }
 152
 153 static GList *
 154 get_connected_drives (GVolumeMonitor *volume_monitor)
 155 {
 156   GUnionVolumeMonitor *monitor;
 157   GVolumeMonitor *child_monitor;
 158   GList *res;
 159   GList *l;
 160
 161   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 162
 163   res = NULL;
 164
 165   g_rec_mutex_lock (&the_volume_monitor_mutex);
 166
 167   for (l = monitor->monitors; l != NULL; l = l->next)
 168     {
 169       child_monitor = l->data;
 170
 171       res = g_list_concat (res, g_volume_monitor_get_connected_drives (child_monitor));
 172     }
 173
 174   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 175
 176   return res;
 177 }
 178
 179 static GVolume *
 180 get_volume_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)
 181 {
 182   GUnionVolumeMonitor *monitor;
 183   GVolumeMonitor *child_monitor;
 184   GVolume *volume;
 185   GList *l;
 186
 187   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 188
 189   volume = NULL;
 190
 191   g_rec_mutex_lock (&the_volume_monitor_mutex);
 192
 193   for (l = monitor->monitors; l != NULL; l = l->next)
 194     {
 195       child_monitor = l->data;
 196
 197       volume = g_volume_monitor_get_volume_for_uuid (child_monitor, uuid);
 198       if (volume != NULL)
 199         break;
 200
 201     }
 202
 203   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 204
 205   return volume;
 206 }
 207
 208 static GMount *
 209 get_mount_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)
 210 {
 211   GUnionVolumeMonitor *monitor;
 212   GVolumeMonitor *child_monitor;
 213   GMount *mount;
 214   GList *l;
 215
 216   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 217
 218   mount = NULL;
 219
 220   g_rec_mutex_lock (&the_volume_monitor_mutex);
 221
 222   for (l = monitor->monitors; l != NULL; l = l->next)
 223     {
 224       child_monitor = l->data;
 225
 226       mount = g_volume_monitor_get_mount_for_uuid (child_monitor, uuid);
 227       if (mount != NULL)
 228         break;
 229
 230     }
 231
 232   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 233
 234   return mount;
 235 }
 236
 237 static void
 238 g_union_volume_monitor_class_init (GUnionVolumeMonitorClass *klass)
 239 {
 240   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 241   GVolumeMonitorClass *monitor_class = G_VOLUME_MONITOR_CLASS (klass);
 242
 243   gobject_class->finalize = g_union_volume_monitor_finalize;
 244   gobject_class->dispose = g_union_volume_monitor_dispose;
 245
 246   monitor_class->get_connected_drives = get_connected_drives;
 247   monitor_class->get_volumes = get_volumes;
 248   monitor_class->get_mounts = get_mounts;
 249   monitor_class->get_volume_for_uuid = get_volume_for_uuid;
 250   monitor_class->get_mount_for_uuid = get_mount_for_uuid;
 251 }
 252
 253 static void
 254 child_volume_added (GVolumeMonitor      *child_monitor,
 255                     GVolume    *child_volume,
 256                     GUnionVolumeMonitor *union_monitor)
 257 {
 258   g_signal_emit_by_name (union_monitor,
 259                          "volume-added",
 260                          child_volume);
 261 }
 262
 263 static void
 264 child_volume_removed (GVolumeMonitor      *child_monitor,
 265                       GVolume    *child_volume,
 266                       GUnionVolumeMonitor *union_monitor)
 267 {
 268   g_signal_emit_by_name (union_monitor,
 269                          "volume-removed",
 270                          child_volume);
 271 }
 272
 273 static void
 274 child_volume_changed (GVolumeMonitor      *child_monitor,
 275                       GVolume    *child_volume,
 276                       GUnionVolumeMonitor *union_monitor)
 277 {
 278   g_signal_emit_by_name (union_monitor,
 279                          "volume-changed",
 280                          child_volume);
 281 }
 282
 283 static void
 284 child_mount_added (GVolumeMonitor      *child_monitor,
 285                    GMount              *child_mount,
 286                    GUnionVolumeMonitor *union_monitor)
 287 {
 288   g_signal_emit_by_name (union_monitor,
 289                          "mount-added",
 290                          child_mount);
 291 }
 292
 293 static void
 294 child_mount_removed (GVolumeMonitor      *child_monitor,
 295                      GMount              *child_mount,
 296                      GUnionVolumeMonitor *union_monitor)
 297 {
 298   g_signal_emit_by_name (union_monitor,
 299                          "mount-removed",
 300                          child_mount);
 301 }
 302
 303 static void
 304 child_mount_pre_unmount (GVolumeMonitor       *child_monitor,
 305                           GMount              *child_mount,
 306                           GUnionVolumeMonitor *union_monitor)
 307 {
 308   g_signal_emit_by_name (union_monitor,
 309                          "mount-pre-unmount",
 310                          child_mount);
 311 }
 312
 313
 314 static void
 315 child_mount_changed (GVolumeMonitor       *child_monitor,
 316                       GMount              *child_mount,
 317                       GUnionVolumeMonitor *union_monitor)
 318 {
 319   g_signal_emit_by_name (union_monitor,
 320                          "mount-changed",
 321                          child_mount);
 322 }
 323
 324 static void
 325 child_drive_connected (GVolumeMonitor      *child_monitor,
 326                        GDrive              *child_drive,
 327                        GUnionVolumeMonitor *union_monitor)
 328 {
 329   g_signal_emit_by_name (union_monitor,
 330                          "drive-connected",
 331                          child_drive);
 332 }
 333
 334 static void
 335 child_drive_disconnected (GVolumeMonitor      *child_monitor,
 336                           GDrive              *child_drive,
 337                           GUnionVolumeMonitor *union_monitor)
 338 {
 339   g_signal_emit_by_name (union_monitor,
 340                          "drive-disconnected",
 341                          child_drive);
 342 }
 343
 344 static void
 345 child_drive_changed (GVolumeMonitor      *child_monitor,
 346                      GDrive             *child_drive,
 347                      GUnionVolumeMonitor *union_monitor)
 348 {
 349   g_signal_emit_by_name (union_monitor,
 350                          "drive-changed",
 351                          child_drive);
 352 }
 353
 354 static void
 355 child_drive_eject_button (GVolumeMonitor      *child_monitor,
 356                           GDrive             *child_drive,
 357                           GUnionVolumeMonitor *union_monitor)
 358 {
 359   g_signal_emit_by_name (union_monitor,
 360                          "drive-eject-button",
 361                          child_drive);
 362 }
 363
 364 static void
 365 child_drive_stop_button (GVolumeMonitor      *child_monitor,
 366                          GDrive             *child_drive,
 367                          GUnionVolumeMonitor *union_monitor)
 368 {
 369   g_signal_emit_by_name (union_monitor,
 370                          "drive-stop-button",
 371                          child_drive);
 372 }
 373
 374 static void
 375 g_union_volume_monitor_add_monitor (GUnionVolumeMonitor *union_monitor,
 376                                     GVolumeMonitor      *volume_monitor)
 377 {
 378   if (g_list_find (union_monitor->monitors, volume_monitor))
 379     return;
 380
 381   union_monitor->monitors =
 382     g_list_prepend (union_monitor->monitors,
 383                     g_object_ref (volume_monitor));
 384
 385   g_signal_connect (volume_monitor, "volume-added", (GCallback)child_volume_added, union_monitor);
 386   g_signal_connect (volume_monitor, "volume-removed", (GCallback)child_volume_removed, union_monitor);
 387   g_signal_connect (volume_monitor, "volume-changed", (GCallback)child_volume_changed, union_monitor);
 388   g_signal_connect (volume_monitor, "mount-added", (GCallback)child_mount_added, union_monitor);
 389   g_signal_connect (volume_monitor, "mount-removed", (GCallback)child_mount_removed, union_monitor);
 390   g_signal_connect (volume_monitor, "mount-pre-unmount", (GCallback)child_mount_pre_unmount, union_monitor);
 391   g_signal_connect (volume_monitor, "mount-changed", (GCallback)child_mount_changed, union_monitor);
 392   g_signal_connect (volume_monitor, "drive-connected", (GCallback)child_drive_connected, union_monitor);
 393   g_signal_connect (volume_monitor, "drive-disconnected", (GCallback)child_drive_disconnected, union_monitor);
 394   g_signal_connect (volume_monitor, "drive-changed", (GCallback)child_drive_changed, union_monitor);
 395   g_signal_connect (volume_monitor, "drive-eject-button", (GCallback)child_drive_eject_button, union_monitor);
 396   g_signal_connect (volume_monitor, "drive-stop-button", (GCallback)child_drive_stop_button, union_monitor);
 397 }
 398
 399 static void
 400 g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,
 401                                        GVolumeMonitor      *child_monitor)
 402 {
 403   GList *l;
 404
 405   l = g_list_find (union_monitor->monitors, child_monitor);
 406   if (l == NULL)
 407     return;
 408
 409   union_monitor->monitors = g_list_delete_link (union_monitor->monitors, l);
 410
 411   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_added, union_monitor);
 412   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_removed, union_monitor);
 413   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_changed, union_monitor);
 414   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_added, union_monitor);
 415   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_removed, union_monitor);
 416   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_pre_unmount, union_monitor);
 417   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_changed, union_monitor);
 418   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_connected, union_monitor);
 419   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_disconnected, union_monitor);
 420   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_changed, union_monitor);
 421   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_eject_button, union_monitor);
 422   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_stop_button, union_monitor);
 423 }
 424
 425 static GType
 426 get_default_native_class (gpointer data)
 427 {
 428   return _g_io_module_get_default_type (G_NATIVE_VOLUME_MONITOR_EXTENSION_POINT_NAME,
 429                                         "GIO_USE_VOLUME_MONITOR",
 430                                         G_STRUCT_OFFSET (GVolumeMonitorClass, is_supported));
 431 }
 432
 433 /* We return the class, with a ref taken.
 434  * This way we avoid unloading the class/module
 435  * between selecting the type and creating the
 436  * instance on the first call.
 437  */
 438 static GNativeVolumeMonitorClass *
 439 get_native_class (void)
 440 {
 441   static GOnce once_init = G_ONCE_INIT;
 442   GTypeClass *type_class;
 443
 444   type_class = NULL;
 445   g_once (&once_init, (GThreadFunc)get_default_native_class, &type_class);
 446
 447   if (type_class == NULL && once_init.retval != GUINT_TO_POINTER(G_TYPE_INVALID))
 448     type_class = g_type_class_ref ((GType)once_init.retval);
 449
 450   return (GNativeVolumeMonitorClass *)type_class;
 451 }
 452
 453 static void
 454 g_union_volume_monitor_init (GUnionVolumeMonitor *union_monitor)
 455 {
 456 }
 457
 458 static void
 459 populate_union_monitor (GUnionVolumeMonitor *union_monitor)
 460 {
 461   GVolumeMonitor *monitor;
 462   GNativeVolumeMonitorClass *native_class;
 463   GVolumeMonitorClass *klass;
 464   GIOExtensionPoint *ep;
 465   GIOExtension *extension;
 466   GList *l;
 467
 468   native_class = get_native_class ();
 469
 470   if (native_class != NULL)
 471     {
 472       monitor = g_object_new (G_TYPE_FROM_CLASS (native_class), NULL);
 473       g_union_volume_monitor_add_monitor (union_monitor, monitor);
 474       g_object_unref (monitor);
 475       g_type_class_unref (native_class);
 476     }
 477
 478   ep = g_io_extension_point_lookup (G_VOLUME_MONITOR_EXTENSION_POINT_NAME);
 479   for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)
 480     {
 481       extension = l->data;
 482
 483       klass = G_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));
 484       if (klass->is_supported == NULL || klass->is_supported())
 485         {
 486           monitor = g_object_new (g_io_extension_get_type (extension), NULL);
 487           g_union_volume_monitor_add_monitor (union_monitor, monitor);
 488           g_object_unref (monitor);
 489         }
 490       g_type_class_unref (klass);
 491     }
 492 }
 493
 494 static GUnionVolumeMonitor *
 495 g_union_volume_monitor_new (void)
 496 {
 497   GUnionVolumeMonitor *monitor;
 498
 499   monitor = g_object_new (G_TYPE_UNION_VOLUME_MONITOR, NULL);
 500
 501   return monitor;
 502 }
 503
 504 /**
 505  * g_volume_monitor_get:
 506  *
 507  * Gets the volume monitor used by gio.
 508  *
 509  * Returns: (transfer full): a reference to the #GVolumeMonitor used by gio. Call
 510  *    g_object_unref() when done with it.
 511  **/
 512 GVolumeMonitor *
 513 g_volume_monitor_get (void)
 514 {
 515   GVolumeMonitor *vm;
 516
 517   g_rec_mutex_lock (&the_volume_monitor_mutex);
 518
 519   if (the_volume_monitor)
 520     vm = G_VOLUME_MONITOR (g_object_ref (the_volume_monitor));
 521   else
 522     {
 523       the_volume_monitor = g_union_volume_monitor_new ();
 524       populate_union_monitor (the_volume_monitor);
 525       vm = G_VOLUME_MONITOR (the_volume_monitor);
 526     }
 527
 528   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 529
 530   return vm;
 531 }
 532
 533 GMount *
 534 _g_mount_get_for_mount_path (const gchar  *mount_path,
 535                              GCancellable *cancellable)
 536 {
 537   GNativeVolumeMonitorClass *klass;
 538   GMount *mount;
 539
 540   klass = get_native_class ();
 541   if (klass == NULL)
 542     return NULL;
 543
 544   mount = NULL;
 545
 546   if (klass->get_mount_for_mount_path)
 547     mount = klass->get_mount_for_mount_path (mount_path, cancellable);
 548
 549   /* TODO: How do we know this succeeded? Keep in mind that the native
 550    *       volume monitor may fail (e.g. not being able to connect to
 551    *       udisks). Is the get_mount_for_mount_path() method allowed to
 552    *       return NULL? Seems like it is ... probably the method needs
 553    *       to take a boolean and write if it succeeds or not.. Messy.
 554    *       Very messy.
 555    */
 556
 557   g_type_class_unref (klass);
 558
 559   return mount;
 560 }
 561
 562 /**
 563  * g_volume_monitor_adopt_orphan_mount:
 564  * @mount: a #GMount object to find a parent for
 565  *
 566  * This function should be called by any #GVolumeMonitor
 567  * implementation when a new #GMount object is created that is not
 568  * associated with a #GVolume object. It must be called just before
 569  * emitting the @mount_added signal.
 570  *
 571  * If the return value is not %NULL, the caller must associate the
 572  * returned #GVolume object with the #GMount. This involves returning
 573  * it in its g_mount_get_volume() implementation. The caller must
 574  * also listen for the "removed" signal on the returned object
 575  * and give up its reference when handling that signal
 576  *
 577  * Similarly, if implementing g_volume_monitor_adopt_orphan_mount(),
 578  * the implementor must take a reference to @mount and return it in
 579  * its g_volume_get_mount() implemented. Also, the implementor must
 580  * listen for the "unmounted" signal on @mount and give up its
 581  * reference upon handling that signal.
 582  *
 583  * There are two main use cases for this function.
 584  *
 585  * One is when implementing a user space file system driver that reads
 586  * blocks of a block device that is already represented by the native
 587  * volume monitor (for example a CD Audio file system driver). Such
 588  * a driver will generate its own #GMount object that needs to be
 589  * associated with the #GVolume object that represents the volume.
 590  *
 591  * The other is for implementing a #GVolumeMonitor whose sole purpose
 592  * is to return #GVolume objects representing entries in the users
 593  * "favorite servers" list or similar.
 594  *
 595  * Returns: (transfer full): the #GVolume object that is the parent for @mount or %NULL
 596  * if no wants to adopt the #GMount.
 597  *
 598  * Deprecated: 2.20: Instead of using this function, #GVolumeMonitor
 599  * implementations should instead create shadow mounts with the URI of
 600  * the mount they intend to adopt. See the proxy volume monitor in
 601  * gvfs for an example of this. Also see g_mount_is_shadowed(),
 602  * g_mount_shadow() and g_mount_unshadow() functions.
 603  */
 604 GVolume *
 605 g_volume_monitor_adopt_orphan_mount (GMount *mount)
 606 {
 607   GVolumeMonitor *child_monitor;
 608   GVolumeMonitorClass *child_monitor_class;
 609   GVolume *volume;
 610   GList *l;
 611
 612   g_return_val_if_fail (mount != NULL, NULL);
 613
 614   if (the_volume_monitor == NULL)
 615     return NULL;
 616
 617   volume = NULL;
 618
 619   g_rec_mutex_lock (&the_volume_monitor_mutex);
 620
 621   for (l = the_volume_monitor->monitors; l != NULL; l = l->next)
 622     {
 623       child_monitor = l->data;
 624       child_monitor_class = G_VOLUME_MONITOR_GET_CLASS (child_monitor);
 625
 626       if (child_monitor_class->adopt_orphan_mount != NULL)
 627         {
 628           volume = child_monitor_class->adopt_orphan_mount (mount, child_monitor);
 629           if (volume != NULL)
 630             break;
 631         }
 632     }
 633
 634   g_rec_mutex_unlock (&the_volume_monitor_mutex);
 635
 636   return volume;
 637 }