macosx: fixed a thread-safety issue in the open panel code

VLC crashed when mounting multiple volumes at once
(cherry picked from commit 35e8ad40158caf05b597d258609cb2c0570eaf0d)

Conflicts:

	modules/gui/macosx/open.m
Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>

modules/gui/macosx/open.m

@@ -802,56 +802,53 @@ static VLCOpen *_o_sharedMainInstance = nil;
     return returnValue;
 }
 
-- (void)showOpticalAtIndex: (NSNumber *)n_index
+- (void)showOpticalAtPath: (NSString *)o_opticalDevicePath
 {
     NSAutoreleasePool * o_pool = [[NSAutoreleasePool alloc] init];
 
-    if (!o_opticalDevices)
-        return;
-
-    if ([o_opticalDevices count] == 0)
-        return;
-
-    unsigned int index = [n_index intValue];
-
-    id o_currentOpticalDevice = [o_opticalDevices objectAtIndex: index];
-    char *diskType = [self getVolumeTypeFromMountPath:o_currentOpticalDevice];
+    char *diskType = [self getVolumeTypeFromMountPath:o_opticalDevicePath];
 
     if (diskType == kVLCMediaDVD || diskType == kVLCMediaVideoTSFolder)
     {
-        [o_disc_dvd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath:o_currentOpticalDevice]];
+        [o_disc_dvd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath:o_opticalDevicePath]];
         [o_disc_dvdwomenus_lbl setStringValue: [o_disc_dvd_lbl stringValue]];
         NSString *pathToOpen;
         if (diskType == kVLCMediaVideoTSFolder)
-            pathToOpen = o_currentOpticalDevice;
+            pathToOpen = o_opticalDevicePath;
         else
-            pathToOpen = [self getBSDNodeFromMountPath: o_currentOpticalDevice];
+            pathToOpen = [self getBSDNodeFromMountPath: o_opticalDevicePath];
         if (!b_nodvdmenus) {
             [self setMRL: [NSString stringWithFormat: @"dvdnav://%@", pathToOpen]];
-            [self showOpticalMediaView: o_disc_dvd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_currentOpticalDevice]];
+            [self showOpticalMediaView: o_disc_dvd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
         } else {
             [self setMRL: [NSString stringWithFormat: @"dvdread://%@#%i:%i-", pathToOpen, [o_disc_dvdwomenus_title intValue], [o_disc_dvdwomenus_chapter intValue]]];
-            [self showOpticalMediaView: o_disc_dvdwomenus_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_currentOpticalDevice]];
+            [self showOpticalMediaView: o_disc_dvdwomenus_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
         }
     }
     else if (diskType == kVLCMediaAudioCD)
     {
-        [o_disc_audiocd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_currentOpticalDevice]];
-        [o_disc_audiocd_trackcount_lbl setStringValue: [NSString stringWithFormat:_NS("%i tracks"), [[[NSFileManager defaultManager] subpathsOfDirectoryAtPath: o_currentOpticalDevice error:NULL] count] - 1]]; // minus .TOC.plist
-        [self showOpticalMediaView: o_disc_audiocd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_currentOpticalDevice]];
-        [self setMRL: [NSString stringWithFormat: @"cdda://%@", [self getBSDNodeFromMountPath: o_currentOpticalDevice]]];
+        [o_disc_audiocd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_opticalDevicePath]];
+        [o_disc_audiocd_trackcount_lbl setStringValue: [NSString stringWithFormat:_NS("%i tracks"), [[[NSFileManager defaultManager] subpathsOfDirectoryAtPath: o_opticalDevicePath error:NULL] count] - 1]]; // minus .TOC.plist
+        [self showOpticalMediaView: o_disc_audiocd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
+        [self setMRL: [NSString stringWithFormat: @"cdda://%@", [self getBSDNodeFromMountPath: o_opticalDevicePath]]];
     }
-    else if (diskType == kVLCMediaVCD || diskType == kVLCMediaSVCD)
+    else if (diskType == kVLCMediaVCD)
     {
-        [o_disc_vcd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_currentOpticalDevice]];
-        [self showOpticalMediaView: o_disc_vcd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_currentOpticalDevice]];
-        [self setMRL: [NSString stringWithFormat: @"vcd://%@@%i:%i", [self getBSDNodeFromMountPath: o_currentOpticalDevice], [o_disc_vcd_title intValue], [o_disc_vcd_chapter intValue]]];
+        [o_disc_vcd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_opticalDevicePath]];
+        [self showOpticalMediaView: o_disc_vcd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
+        [self setMRL: [NSString stringWithFormat: @"vcd://%@#%i:%i", [self getBSDNodeFromMountPath: o_opticalDevicePath], [o_disc_vcd_title intValue], [o_disc_vcd_chapter intValue]]];
+    }
+    else if (diskType == kVLCMediaSVCD)
+    {
+        [o_disc_vcd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_opticalDevicePath]];
+        [self showOpticalMediaView: o_disc_vcd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
+        [self setMRL: [NSString stringWithFormat: @"vcd://%@@%i:%i", [self getBSDNodeFromMountPath: o_opticalDevicePath], [o_disc_vcd_title intValue], [o_disc_vcd_chapter intValue]]];
     }
     else if (diskType == kVLCMediaBD || diskType == kVLCMediaBDMVFolder)
     {
-        [o_disc_bd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_currentOpticalDevice]];
-        [self showOpticalMediaView: o_disc_bd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_currentOpticalDevice]];
-        [self setMRL: [NSString stringWithFormat: @"bluray://%@", o_currentOpticalDevice]];
+        [o_disc_bd_lbl setStringValue: [[NSFileManager defaultManager] displayNameAtPath: o_opticalDevicePath]];
+        [self showOpticalMediaView: o_disc_bd_view withIcon: [[NSWorkspace sharedWorkspace] iconForFile: o_opticalDevicePath]];
+        [self setMRL: [NSString stringWithFormat: @"bluray://%@", o_opticalDevicePath]];
     }
     else
     {
@@ -862,12 +859,17 @@ static VLCOpen *_o_sharedMainInstance = nil;
     [o_pool release];
 }
 
+- (void)showSelectedOpticalDisc
+{
+    NSString *o_opticalDevicePath = [o_opticalDevices objectAtIndex:[o_disc_selector_pop indexOfSelectedItem]];
+    [NSThread detachNewThreadSelector:@selector(showOpticalAtPath:) toTarget:self withObject:o_opticalDevicePath];
+}
+
 - (void)scanOpticalMedia:(NSNotification *)o_notification
 {
     [o_opticalDevices removeAllObjects];
     [o_disc_selector_pop removeAllItems];
     [o_opticalDevices addObjectsFromArray: [[NSWorkspace sharedWorkspace] mountedRemovableMedia]];
-    if ([o_specialMediaFolders count] > 0)
     [o_opticalDevices addObjectsFromArray: o_specialMediaFolders];
     if ([o_opticalDevices count] > 0) {
         NSUInteger deviceCount = [o_opticalDevices count];
@@ -879,7 +881,7 @@ static VLCOpen *_o_sharedMainInstance = nil;
         else
             [o_disc_selector_pop setHidden: NO];
 
-        [NSThread detachNewThreadSelector:@selector(showOpticalAtIndex:) toTarget:self withObject:[NSNumber numberWithInt:[o_disc_selector_pop indexOfSelectedItem]]];
+        [self showSelectedOpticalDisc];
     }
     else
     {
@@ -891,7 +893,7 @@ static VLCOpen *_o_sharedMainInstance = nil;
 
 - (IBAction)discSelectorChanged:(id)sender
 {
-    [NSThread detachNewThreadSelector:@selector(showOpticalAtIndex:) toTarget:self withObject:[NSNumber numberWithInt:[o_disc_selector_pop indexOfSelectedItem]]];
+    [self showSelectedOpticalDisc];
 }
 
 - (IBAction)openSpecialMediaFolder:(id)sender