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 /* Note: This compares in reverse order.
 394    Higher prio -> sort first
 395  */
 396 static gint
 397 compare_monitor_type (gconstpointer  a,
 398                       gconstpointer  b,
 399                       gpointer       user_data)
 400 {
 401   GNativeVolumeMonitorClass *class_a, *class_b;
 402   gint res;
 403   const char *use_this_monitor;
 404
 405   /* We ref:ed all the classes, so the peek is safe */
 406   class_a = g_type_class_peek (*(GType *)a);
 407   class_b = g_type_class_peek (*(GType *)b);
 408   use_this_monitor = user_data;
 409
 410   if (class_a == class_b)
 411     res = 0;
 412   else if (use_this_monitor != NULL &&
 413            strcmp (class_a->name, use_this_monitor) == 0)
 414     res = -1;
 415   else if (use_this_monitor != NULL &&
 416            strcmp (class_b->name, use_this_monitor) == 0)
 417     res = 1;
 418   else
 419     res = class_b->priority - class_a->priority;
 420
 421   return res;
 422 }
 423
 424 static GTypeClass *
 425 get_default_native_class (gpointer data)
 426 {
 427   GNativeVolumeMonitorClass *klass;
 428   GType *monitors;
 429   guint n_monitors;
 430   GTypeClass *native_class;
 431   const char *use_this;
 432   int i;
 433
 434   use_this = g_getenv ("GIO_USE_VOLUME_MONITOR");
 435
 436 #ifdef G_OS_UNIX
 437   /* Ensure GUnixVolumeMonitor type is available */
 438   {
 439     volatile GType unix_type;
 440     /* volatile is required to avoid any G_GNUC_CONST optimizations */
 441     unix_type = _g_unix_volume_monitor_get_type ();
 442   }
 443 #endif
 444
 445   /* Ensure vfs in modules loaded */
 446   _g_io_modules_ensure_loaded ();
 447
 448   monitors = g_type_children (G_TYPE_NATIVE_VOLUME_MONITOR, &n_monitors);
 449
 450   /* Ref all classes once so we don't load/unload them a lot */
 451   for (i = 0; i < n_monitors; i++)
 452     g_type_class_ref (monitors[i]);
 453
 454   g_qsort_with_data (monitors, n_monitors, sizeof (GType),
 455                      compare_monitor_type, (gpointer)use_this);
 456
 457   native_class = NULL;
 458   for (i = 0; i < n_monitors; i++)
 459     {
 460       klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_type_class_ref (monitors[i]));
 461
 462       if (klass->is_supported ())
 463         {
 464           native_class = (GTypeClass *)klass;
 465           break;
 466         }
 467       g_type_class_unref (klass);
 468     }
 469
 470   for (i = 0; i < n_monitors; i++)
 471     g_type_class_unref (g_type_class_peek (monitors[i]));
 472
 473   g_free (monitors);
 474
 475   return native_class;
 476 }
 477
 478
 479 static GType
 480 get_native_type ()
 481 {
 482   static GOnce _once_init = G_ONCE_INIT;
 483
 484   g_once (&_once_init, (GThreadFunc)get_default_native_class, NULL);
 485
 486   return G_TYPE_FROM_CLASS (_once_init.retval);
 487 }
 488
 489 static void
 490 g_union_volume_monitor_init (GUnionVolumeMonitor *union_monitor)
 491 {
 492   GVolumeMonitor *monitor;
 493   GType *monitors;
 494   guint n_monitors;
 495   GType native_type;
 496   int i;
 497
 498   native_type = get_native_type ();
 499
 500   if (native_type != G_TYPE_INVALID)
 501     {
 502       monitor = g_object_new (native_type, NULL);
 503       g_union_volume_monitor_add_monitor (union_monitor, monitor);
 504       g_object_unref (monitor);
 505     }
 506
 507   monitors = g_type_children (G_TYPE_VOLUME_MONITOR, &n_monitors);
 508
 509   for (i = 0; i < n_monitors; i++)
 510     {
 511       if (monitors[i] == G_TYPE_UNION_VOLUME_MONITOR ||
 512           g_type_is_a (monitors[i], G_TYPE_NATIVE_VOLUME_MONITOR))
 513         continue;
 514
 515       monitor = g_object_new (monitors[i], NULL);
 516       g_union_volume_monitor_add_monitor (union_monitor, monitor);
 517       g_object_unref (monitor);
 518     }
 519
 520   g_free (monitors);
 521 }
 522
 523 static GUnionVolumeMonitor *
 524 g_union_volume_monitor_new (void)
 525 {
 526   GUnionVolumeMonitor *monitor;
 527
 528   monitor = g_object_new (G_TYPE_UNION_VOLUME_MONITOR, NULL);
 529
 530   return monitor;
 531 }
 532
 533 /**
 534  * g_volume_monitor_get:
 535  *
 536  * Gets the volume monitor used by gio.
 537  *
 538  * Returns: a reference to the #GVolumeMonitor used by gio. Call
 539  *    g_object_unref() when done with it.
 540  **/
 541 GVolumeMonitor *
 542 g_volume_monitor_get (void)
 543 {
 544   GVolumeMonitor *vm;
 545
 546   G_LOCK (the_volume_monitor);
 547
 548   if (the_volume_monitor)
 549     vm = G_VOLUME_MONITOR (g_object_ref (the_volume_monitor));
 550   else
 551     {
 552       the_volume_monitor = g_union_volume_monitor_new ();
 553       vm = G_VOLUME_MONITOR (the_volume_monitor);
 554     }
 555
 556   G_UNLOCK (the_volume_monitor);
 557
 558   return vm;
 559 }
 560
 561 /**
 562  * _g_mount_get_for_mount_path:
 563  * @mountpoint: a string.
 564  * @cancellable: a #GCancellable, or %NULL
 565  *
 566  * Returns: a #GMount for given @mount_path or %NULL.
 567  **/
 568 GMount *
 569 _g_mount_get_for_mount_path (const char *mount_path,
 570                              GCancellable *cancellable)
 571 {
 572   GType native_type;
 573   GNativeVolumeMonitorClass *klass;
 574   GMount *mount;
 575
 576   native_type = get_native_type ();
 577
 578   if (native_type == G_TYPE_INVALID)
 579     return NULL;
 580
 581   mount = NULL;
 582
 583   klass = G_NATIVE_VOLUME_MONITOR_CLASS (g_type_class_ref (native_type));
 584   if (klass->get_mount_for_mount_path)
 585     {
 586       G_LOCK (the_volume_monitor);
 587       mount = klass->get_mount_for_mount_path (mount_path, cancellable);
 588       G_UNLOCK (the_volume_monitor);
 589     }
 590
 591   /* TODO: How do we know this succeeded? Keep in mind that the native
 592    *       volume monitor may fail (e.g. not being able to connect to
 593    *       hald). Is the get_mount_for_mount_path() method allowed to
 594    *       return NULL? Seems like it is ... probably the method needs
 595    *       to take a boolean and write if it succeeds or not.. Messy.
 596    *       Very messy.
 597    */
 598
 599   g_type_class_unref (klass);
 600
 601   return mount;
 602 }
 603
 604 /**
 605  * g_volume_monitor_adopt_orphan_mount:
 606  * @mount: a #GMount object to find a parent for
 607  *
 608  * This function should be called by any #GVolumeMonitor
 609  * implementation when a new #GMount object is created that is not
 610  * associated with a #GVolume object. It must be called just before
 611  * emitting the @mount_added signal.
 612  *
 613  * If the return value is not %NULL, the caller must associate the
 614  * returned #GVolume object with the #GMount. This involves returning
 615  * it in it's g_mount_get_volume() implementation. The caller must
 616  * also listen for the "removed" signal on the returned object
 617  * and give up it's reference when handling that signal
 618  *
 619  * Similary, if implementing g_volume_monitor_adopt_orphan_mount(),
 620  * the implementor must take a reference to @mount and return it in
 621  * it's g_volume_get_mount() implemented. Also, the implementor must
 622  * listen for the "unmounted" signal on @mount and give up it's
 623  * reference upon handling that signal.
 624  *
 625  * There are two main use cases for this function.
 626  *
 627  * One is when implementing a user space file system driver that reads
 628  * blocks of a block device that is already represented by the native
 629  * volume monitor (for example a CD Audio file system driver). Such
 630  * a driver will generate it's own #GMount object that needs to be
 631  * assoicated with the #GVolume object that represents the volume.
 632  *
 633  * The other is for implementing a #GVolumeMonitor whose sole purpose
 634  * is to return #GVolume objects representing entries in the users
 635  * "favorite servers" list or similar.
 636  *
 637  * Returns: the #GVolume object that is the parent for @mount or %NULL
 638  * if no wants to adopt the #GMount.
 639  */
 640 GVolume *
 641 g_volume_monitor_adopt_orphan_mount (GMount *mount)
 642 {
 643   GVolumeMonitor *child_monitor;
 644   GVolumeMonitorClass *child_monitor_class;
 645   GVolume *volume;
 646   GList *l;
 647
 648   g_return_val_if_fail (mount != NULL, NULL);
 649
 650   if (the_volume_monitor == NULL)
 651     return NULL;
 652
 653   volume = NULL;
 654
 655   /* TODO: nasty locking issues because current VM's don't emit signals in idle */
 656
 657   //G_LOCK (the_volume_monitor);
 658
 659   for (l = the_volume_monitor->monitors; l != NULL; l = l->next)
 660     {
 661       child_monitor = l->data;
 662       child_monitor_class = G_VOLUME_MONITOR_GET_CLASS (child_monitor);
 663
 664       if (child_monitor_class->adopt_orphan_mount != NULL)
 665         {
 666           volume = child_monitor_class->adopt_orphan_mount (mount);
 667           if (volume != NULL)
 668             break;
 669         }
 670     }
 671
 672   //G_UNLOCK (the_volume_monitor);
 673
 674   return volume;
 675 }
 676
 677
 678 #define __G_UNION_VOLUME_MONITOR_C__
 679 #include "gioaliasdef.c"