gio/gunionvolumemonitor.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2007 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: Alexander Larsson <alexl@redhat.com>
  21  *         David Zeuthen <davidz@redhat.com>
  22  */
  23
  24 #include <config.h>
  25
  26 #include <string.h>
  27
  28 #include <glib.h>
  29 #include "gunionvolumemonitor.h"
  30 #include "gmountprivate.h"
  31 #include "giomodule-priv.h"
  32 #ifdef G_OS_UNIX
  33 #include "gunixvolumemonitor.h"
  34 #endif
  35 #include "gnativevolumemonitor.h"
  36
  37 #include "glibintl.h"
  38
  39 #include "gioalias.h"
  40
  41 struct _GUnionVolumeMonitor {
  42   GVolumeMonitor parent;
  43
  44   GList *monitors;
  45 };
  46
  47 static void g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,
  48                                                    GVolumeMonitor *child_monitor);
  49
  50
  51 #define g_union_volume_monitor_get_type _g_union_volume_monitor_get_type
  52 G_DEFINE_TYPE (GUnionVolumeMonitor, g_union_volume_monitor, G_TYPE_VOLUME_MONITOR);
  53
  54
  55 G_LOCK_DEFINE_STATIC(the_volume_monitor);
  56 static GUnionVolumeMonitor *the_volume_monitor = NULL;
  57
  58 static void
  59 g_union_volume_monitor_finalize (GObject *object)
  60 {
  61   GUnionVolumeMonitor *monitor;
  62   GVolumeMonitor *child_monitor;
  63
  64   monitor = G_UNION_VOLUME_MONITOR (object);
  65
  66   while (monitor->monitors != NULL) {
  67     child_monitor = monitor->monitors->data;
  68     g_union_volume_monitor_remove_monitor (monitor,
  69                                            child_monitor);
  70     g_object_unref (child_monitor);
  71   }
  72
  73
  74   if (G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->finalize)
  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
  83   monitor = G_UNION_VOLUME_MONITOR (object);
  84
  85   G_LOCK (the_volume_monitor);
  86   the_volume_monitor = NULL;
  87   G_UNLOCK (the_volume_monitor);
  88
  89   if (G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->dispose)
  90     (*G_OBJECT_CLASS (g_union_volume_monitor_parent_class)->dispose) (object);
  91 }
  92
  93 static GList *
  94 get_mounts (GVolumeMonitor *volume_monitor)
  95 {
  96   GUnionVolumeMonitor *monitor;
  97   GVolumeMonitor *child_monitor;
  98   GList *res;
  99   GList *l;
 100
 101   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 102
 103   res = NULL;
 104
 105   G_LOCK (the_volume_monitor);
 106
 107   for (l = monitor->monitors; l != NULL; l = l->next)
 108     {
 109       child_monitor = l->data;
 110
 111       res = g_list_concat (res, g_volume_monitor_get_mounts (child_monitor));
 112     }
 113
 114   G_UNLOCK (the_volume_monitor);
 115
 116   return res;
 117 }
 118
 119 static GList *
 120 get_volumes (GVolumeMonitor *volume_monitor)
 121 {
 122   GUnionVolumeMonitor *monitor;
 123   GVolumeMonitor *child_monitor;
 124   GList *res;
 125   GList *l;
 126
 127   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 128
 129   res = NULL;
 130
 131   G_LOCK (the_volume_monitor);
 132
 133   for (l = monitor->monitors; l != NULL; l = l->next)
 134     {
 135       child_monitor = l->data;
 136
 137       res = g_list_concat (res, g_volume_monitor_get_volumes (child_monitor));
 138     }
 139
 140   G_UNLOCK (the_volume_monitor);
 141
 142   return res;
 143 }
 144
 145 static GList *
 146 get_connected_drives (GVolumeMonitor *volume_monitor)
 147 {
 148   GUnionVolumeMonitor *monitor;
 149   GVolumeMonitor *child_monitor;
 150   GList *res;
 151   GList *l;
 152
 153   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 154
 155   res = NULL;
 156
 157   G_LOCK (the_volume_monitor);
 158
 159   for (l = monitor->monitors; l != NULL; l = l->next)
 160     {
 161       child_monitor = l->data;
 162
 163       res = g_list_concat (res, g_volume_monitor_get_connected_drives (child_monitor));
 164     }
 165
 166   G_UNLOCK (the_volume_monitor);
 167
 168   return res;
 169 }
 170
 171 static GVolume *
 172 get_volume_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)
 173 {
 174   GUnionVolumeMonitor *monitor;
 175   GVolumeMonitor *child_monitor;
 176   GVolume *volume;
 177   GList *l;
 178
 179   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 180
 181   volume = NULL;
 182
 183   G_LOCK (the_volume_monitor);
 184
 185   for (l = monitor->monitors; l != NULL; l = l->next)
 186     {
 187       child_monitor = l->data;
 188
 189       volume = g_volume_monitor_get_volume_for_uuid (child_monitor, uuid);
 190       if (volume != NULL)
 191         break;
 192
 193     }
 194
 195   G_UNLOCK (the_volume_monitor);
 196
 197   return volume;
 198 }
 199
 200 static GMount *
 201 get_mount_for_uuid (GVolumeMonitor *volume_monitor, const char *uuid)
 202 {
 203   GUnionVolumeMonitor *monitor;
 204   GVolumeMonitor *child_monitor;
 205   GMount *mount;
 206   GList *l;
 207
 208   monitor = G_UNION_VOLUME_MONITOR (volume_monitor);
 209
 210   mount = NULL;
 211
 212   G_LOCK (the_volume_monitor);
 213
 214   for (l = monitor->monitors; l != NULL; l = l->next)
 215     {
 216       child_monitor = l->data;
 217
 218       mount = g_volume_monitor_get_mount_for_uuid (child_monitor, uuid);
 219       if (mount != NULL)
 220         break;
 221
 222     }
 223
 224   G_UNLOCK (the_volume_monitor);
 225
 226   return mount;
 227 }
 228
 229 static void
 230 g_union_volume_monitor_class_init (GUnionVolumeMonitorClass *klass)
 231 {
 232   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 233   GVolumeMonitorClass *monitor_class = G_VOLUME_MONITOR_CLASS (klass);
 234
 235   gobject_class->finalize = g_union_volume_monitor_finalize;
 236   gobject_class->dispose = g_union_volume_monitor_dispose;
 237
 238   monitor_class->get_connected_drives = get_connected_drives;
 239   monitor_class->get_volumes = get_volumes;
 240   monitor_class->get_mounts = get_mounts;
 241   monitor_class->get_volume_for_uuid = get_volume_for_uuid;
 242   monitor_class->get_mount_for_uuid = get_mount_for_uuid;
 243 }
 244
 245 static void
 246 child_volume_added (GVolumeMonitor      *child_monitor,
 247                     GVolume    *child_volume,
 248                     GUnionVolumeMonitor *union_monitor)
 249 {
 250   g_signal_emit_by_name (union_monitor,
 251                          "volume_added",
 252                          child_volume);
 253 }
 254
 255 static void
 256 child_volume_removed (GVolumeMonitor      *child_monitor,
 257                       GVolume    *child_volume,
 258                       GUnionVolumeMonitor *union_monitor)
 259 {
 260   g_signal_emit_by_name (union_monitor,
 261                          "volume_removed",
 262                          child_volume);
 263 }
 264
 265 static void
 266 child_volume_changed (GVolumeMonitor      *child_monitor,
 267                       GVolume    *child_volume,
 268                       GUnionVolumeMonitor *union_monitor)
 269 {
 270   g_signal_emit_by_name (union_monitor,
 271                          "volume_changed",
 272                          child_volume);
 273 }
 274
 275 static void
 276 child_mount_added (GVolumeMonitor      *child_monitor,
 277                    GMount              *child_mount,
 278                    GUnionVolumeMonitor *union_monitor)
 279 {
 280   g_signal_emit_by_name (union_monitor,
 281                          "mount_added",
 282                          child_mount);
 283 }
 284
 285 static void
 286 child_mount_removed (GVolumeMonitor      *child_monitor,
 287                      GMount              *child_mount,
 288                      GUnionVolumeMonitor *union_monitor)
 289 {
 290   g_signal_emit_by_name (union_monitor,
 291                          "mount_removed",
 292                          child_mount);
 293 }
 294
 295 static void
 296 child_mount_pre_unmount (GVolumeMonitor       *child_monitor,
 297                           GMount              *child_mount,
 298                           GUnionVolumeMonitor *union_monitor)
 299 {
 300   g_signal_emit_by_name (union_monitor,
 301                          "mount_pre_unmount",
 302                          child_mount);
 303 }
 304
 305
 306 static void
 307 child_mount_changed (GVolumeMonitor       *child_monitor,
 308                       GMount              *child_mount,
 309                       GUnionVolumeMonitor *union_monitor)
 310 {
 311   g_signal_emit_by_name (union_monitor,
 312                          "mount_changed",
 313                          child_mount);
 314 }
 315
 316 static void
 317 child_drive_connected (GVolumeMonitor      *child_monitor,
 318                        GDrive              *child_drive,
 319                        GUnionVolumeMonitor *union_monitor)
 320 {
 321   g_signal_emit_by_name (union_monitor,
 322                          "drive_connected",
 323                          child_drive);
 324 }
 325
 326 static void
 327 child_drive_disconnected (GVolumeMonitor      *child_monitor,
 328                           GDrive              *child_drive,
 329                           GUnionVolumeMonitor *union_monitor)
 330 {
 331   g_signal_emit_by_name (union_monitor,
 332                          "drive_disconnected",
 333                          child_drive);
 334 }
 335
 336 static void
 337 child_drive_changed (GVolumeMonitor      *child_monitor,
 338                      GDrive             *child_drive,
 339                      GUnionVolumeMonitor *union_monitor)
 340 {
 341   g_signal_emit_by_name (union_monitor,
 342                          "drive_changed",
 343                          child_drive);
 344 }
 345
 346 static void
 347 g_union_volume_monitor_add_monitor (GUnionVolumeMonitor *union_monitor,
 348                                     GVolumeMonitor      *volume_monitor)
 349 {
 350   if (g_list_find (union_monitor->monitors, volume_monitor))
 351     return;
 352
 353   union_monitor->monitors =
 354     g_list_prepend (union_monitor->monitors,
 355                     g_object_ref (volume_monitor));
 356
 357   g_signal_connect (volume_monitor, "volume_added", (GCallback)child_volume_added, union_monitor);
 358   g_signal_connect (volume_monitor, "volume_removed", (GCallback)child_volume_removed, union_monitor);
 359   g_signal_connect (volume_monitor, "volume_changed", (GCallback)child_volume_changed, union_monitor);
 360   g_signal_connect (volume_monitor, "mount_added", (GCallback)child_mount_added, union_monitor);
 361   g_signal_connect (volume_monitor, "mount_removed", (GCallback)child_mount_removed, union_monitor);
 362   g_signal_connect (volume_monitor, "mount_pre_unmount", (GCallback)child_mount_pre_unmount, union_monitor);
 363   g_signal_connect (volume_monitor, "mount_changed", (GCallback)child_mount_changed, union_monitor);
 364   g_signal_connect (volume_monitor, "drive_connected", (GCallback)child_drive_connected, union_monitor);
 365   g_signal_connect (volume_monitor, "drive_disconnected", (GCallback)child_drive_disconnected, union_monitor);
 366   g_signal_connect (volume_monitor, "drive_changed", (GCallback)child_drive_changed, union_monitor);
 367 }
 368
 369 static void
 370 g_union_volume_monitor_remove_monitor (GUnionVolumeMonitor *union_monitor,
 371                                        GVolumeMonitor      *child_monitor)
 372 {
 373   GList *l;
 374
 375   l = g_list_find (union_monitor->monitors, child_monitor);
 376   if (l == NULL)
 377     return;
 378
 379   union_monitor->monitors = g_list_delete_link (union_monitor->monitors, l);
 380
 381   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_added, union_monitor);
 382   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_removed, union_monitor);
 383   g_signal_handlers_disconnect_by_func (child_monitor, child_volume_changed, union_monitor);
 384   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_added, union_monitor);
 385   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_removed, union_monitor);
 386   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_pre_unmount, union_monitor);
 387   g_signal_handlers_disconnect_by_func (child_monitor, child_mount_changed, union_monitor);
 388   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_connected, union_monitor);
 389   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_disconnected, union_monitor);
 390   g_signal_handlers_disconnect_by_func (child_monitor, child_drive_changed, union_monitor);
 391 }
 392
 393 static GType
 394 get_default_native_class (gpointer data)
 395 {
 396   GNativeVolumeMonitorClass *klass, *native_class, **native_class_out;
 397   const char *use_this;
 398   GIOExtensionPoint *ep;
 399   GIOExtension *extension;
 400   GList *l;
 401
 402   native_class_out = data;
 403
 404   use_this = g_getenv ("GIO_USE_VOLUME_MONITOR");
 405
 406   /* Ensure vfs in modules loaded */
 407   _g_io_modules_ensure_loaded ();
 408
 409   ep = g_io_extension_point_lookup (G_NATIVE_VOLUME_MONITOR_EXTENSION_POINT_NAME);
 410
 411   native_class = NULL;
 412   if (use_this)
 413     {
 414       extension = g_io_extension_point_get_extension_by_name (ep, use_this);
 415       if (extension)
 416         {
 417           klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));
 418           if (G_VOLUME_MONITOR_CLASS (klass)->is_supported())
 419             native_class = klass;
 420           else
 421             g_type_class_unref (klass);
 422         }
 423     }
 424
 425   if (native_class == NULL)
 426     {
 427       for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)
 428         {
 429           extension = l->data;
 430           klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));
 431           if (G_VOLUME_MONITOR_CLASS (klass)->is_supported())
 432             {
 433               native_class = klass;
 434               break;
 435             }
 436           else
 437             g_type_class_unref (klass);
 438         }
 439     }
 440
 441   if (native_class)
 442     {
 443       *native_class_out = native_class;
 444       return G_TYPE_FROM_CLASS (native_class);
 445     }
 446   else
 447     return G_TYPE_INVALID;
 448 }
 449
 450 /* We return the class, with a ref taken.
 451  * This way we avoid unloading the class/module
 452  * between selecting the type and creating the
 453  * instance on the first call.
 454  */
 455 static GNativeVolumeMonitorClass *
 456 get_native_class ()
 457 {
 458   static GOnce once_init = G_ONCE_INIT;
 459   GTypeClass *type_class;
 460
 461   type_class = NULL;
 462   g_once (&once_init, (GThreadFunc)get_default_native_class, &type_class);
 463
 464   if (type_class == NULL && once_init.retval != G_TYPE_INVALID)
 465     type_class = g_type_class_ref ((GType)once_init.retval);
 466
 467   return (GNativeVolumeMonitorClass *)type_class;
 468 }
 469
 470 static void
 471 g_union_volume_monitor_init (GUnionVolumeMonitor *union_monitor)
 472 {
 473   GVolumeMonitor *monitor;
 474   GNativeVolumeMonitorClass *native_class;
 475   GVolumeMonitorClass *klass;
 476   GIOExtensionPoint *ep;
 477   GIOExtension *extension;
 478   GList *l;
 479
 480   native_class = get_native_class ();
 481
 482   if (native_class != NULL)
 483     {
 484       monitor = g_object_new (G_TYPE_FROM_CLASS (native_class), NULL);
 485       g_union_volume_monitor_add_monitor (union_monitor, monitor);
 486       g_object_unref (monitor);
 487       g_type_class_unref (native_class);
 488     }
 489
 490   ep = g_io_extension_point_lookup (G_VOLUME_MONITOR_EXTENSION_POINT_NAME);
 491   for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)
 492     {
 493       extension = l->data;
 494
 495       klass = G_VOLUME_MONITOR_CLASS (g_io_extension_ref_class (extension));
 496       if (klass->is_supported == NULL || klass->is_supported())
 497         {
 498           monitor = g_object_new (g_io_extension_get_type (extension), NULL);
 499           g_union_volume_monitor_add_monitor (union_monitor, monitor);
 500           g_object_unref (monitor);
 501         }
 502       g_type_class_unref (klass);
 503     }
 504 }
 505
 506 static GUnionVolumeMonitor *
 507 g_union_volume_monitor_new (void)
 508 {
 509   GUnionVolumeMonitor *monitor;
 510
 511   monitor = g_object_new (G_TYPE_UNION_VOLUME_MONITOR, NULL);
 512
 513   return monitor;
 514 }
 515
 516 /**
 517  * g_volume_monitor_get:
 518  *
 519  * Gets the volume monitor used by gio.
 520  *
 521  * Returns: a reference to the #GVolumeMonitor used by gio. Call
 522  *    g_object_unref() when done with it.
 523  **/
 524 GVolumeMonitor *
 525 g_volume_monitor_get (void)
 526 {
 527   GVolumeMonitor *vm;
 528
 529   G_LOCK (the_volume_monitor);
 530
 531   if (the_volume_monitor)
 532     vm = G_VOLUME_MONITOR (g_object_ref (the_volume_monitor));
 533   else
 534     {
 535       the_volume_monitor = g_union_volume_monitor_new ();
 536       vm = G_VOLUME_MONITOR (the_volume_monitor);
 537     }
 538
 539   G_UNLOCK (the_volume_monitor);
 540
 541   return vm;
 542 }
 543
 544 /**
 545  * _g_mount_get_for_mount_path:
 546  * @mountpoint: a string.
 547  * @cancellable: a #GCancellable, or %NULL
 548  *
 549  * Returns: a #GMount for given @mount_path or %NULL.
 550  **/
 551 GMount *
 552 _g_mount_get_for_mount_path (const char *mount_path,
 553                              GCancellable *cancellable)
 554 {
 555   GNativeVolumeMonitorClass *klass;
 556   GMount *mount;
 557
 558   klass = get_native_class ();
 559   if (klass == NULL)
 560     return NULL;
 561
 562   mount = NULL;
 563
 564   if (klass->get_mount_for_mount_path)
 565     {
 566       G_LOCK (the_volume_monitor);
 567       mount = klass->get_mount_for_mount_path (mount_path, cancellable);
 568       G_UNLOCK (the_volume_monitor);
 569     }
 570
 571   /* TODO: How do we know this succeeded? Keep in mind that the native
 572    *       volume monitor may fail (e.g. not being able to connect to
 573    *       hald). Is the get_mount_for_mount_path() method allowed to
 574    *       return NULL? Seems like it is ... probably the method needs
 575    *       to take a boolean and write if it succeeds or not.. Messy.
 576    *       Very messy.
 577    */
 578
 579   g_type_class_unref (klass);
 580
 581   return mount;
 582 }
 583
 584 /**
 585  * g_volume_monitor_adopt_orphan_mount:
 586  * @mount: a #GMount object to find a parent for
 587  *
 588  * This function should be called by any #GVolumeMonitor
 589  * implementation when a new #GMount object is created that is not
 590  * associated with a #GVolume object. It must be called just before
 591  * emitting the @mount_added signal.
 592  *
 593  * If the return value is not %NULL, the caller must associate the
 594  * returned #GVolume object with the #GMount. This involves returning
 595  * it in it's g_mount_get_volume() implementation. The caller must
 596  * also listen for the "removed" signal on the returned object
 597  * and give up it's reference when handling that signal
 598  *
 599  * Similary, if implementing g_volume_monitor_adopt_orphan_mount(),
 600  * the implementor must take a reference to @mount and return it in
 601  * it's g_volume_get_mount() implemented. Also, the implementor must
 602  * listen for the "unmounted" signal on @mount and give up it's
 603  * reference upon handling that signal.
 604  *
 605  * There are two main use cases for this function.
 606  *
 607  * One is when implementing a user space file system driver that reads
 608  * blocks of a block device that is already represented by the native
 609  * volume monitor (for example a CD Audio file system driver). Such
 610  * a driver will generate it's own #GMount object that needs to be
 611  * assoicated with the #GVolume object that represents the volume.
 612  *
 613  * The other is for implementing a #GVolumeMonitor whose sole purpose
 614  * is to return #GVolume objects representing entries in the users
 615  * "favorite servers" list or similar.
 616  *
 617  * Returns: the #GVolume object that is the parent for @mount or %NULL
 618  * if no wants to adopt the #GMount.
 619  */
 620 GVolume *
 621 g_volume_monitor_adopt_orphan_mount (GMount *mount)
 622 {
 623   GVolumeMonitor *child_monitor;
 624   GVolumeMonitorClass *child_monitor_class;
 625   GVolume *volume;
 626   GList *l;
 627
 628   g_return_val_if_fail (mount != NULL, NULL);
 629
 630   if (the_volume_monitor == NULL)
 631     return NULL;
 632
 633   volume = NULL;
 634
 635   /* TODO: nasty locking issues because current VM's don't emit signals in idle */
 636
 637   /*G_LOCK (the_volume_monitor);*/
 638
 639   for (l = the_volume_monitor->monitors; l != NULL; l = l->next)
 640     {
 641       child_monitor = l->data;
 642       child_monitor_class = G_VOLUME_MONITOR_GET_CLASS (child_monitor);
 643
 644       if (child_monitor_class->adopt_orphan_mount != NULL)
 645         {
 646           volume = child_monitor_class->adopt_orphan_mount (mount);
 647           if (volume != NULL)
 648             break;
 649         }
 650     }
 651
 652   /*G_UNLOCK (the_volume_monitor);*/
 653
 654   return volume;
 655 }
 656
 657
 658 #define __G_UNION_VOLUME_MONITOR_C__
 659 #include "gioaliasdef.c"