tor-browser

commit 4a916f94b05deff8b34f00bcbefb2cf02bb72b2d
parent 69e6e8511d0bc0aefbdfa1573b284502ac87b1b9
Author: Stephen A Pohl <spohl@mozilla.com>
Date:   Tue,  9 Dec 2025 00:52:19 +0000

Bug 1947539: Ensure that not more than one app modal dialog can be opened on macOS. r=mac-reviewers,bradwerth

macOS itself does not guarantee that only one app modal dialog is opened when the various NS*Panel's `runModal` methods are executed. This patch ensures that these panels are truly app modal to prevent various undesirable bugs, such as browser windows not responding to clicks anymore.

Differential Revision: https://phabricator.services.mozilla.com/D275526

Diffstat:
M
widget/cocoa/nsCocoaUtils.h
 | 
7
++++++-
M
widget/cocoa/nsCocoaUtils.mm
 | 
31
++++++++++++++++++++++++++-----
M
widget/cocoa/nsFilePicker.mm
 | 
12
+++++++++---
M
widget/cocoa/nsPrintDialogX.mm
 | 
4
+++-

4 files changed, 44 insertions(+), 10 deletions(-)
diff --git a/widget/cocoa/nsCocoaUtils.h b/widget/cocoa/nsCocoaUtils.h
@@ -250,7 +250,12 @@ class nsCocoaUtils {
    */
   static BOOL ShouldRestoreStateDueToLaunchAtLogin();
 
-  static void PrepareForNativeAppModalDialog();
+  /**
+   * Returns true if the application is ready to run an app modal dialog, false
+   * otherwise. This has to be balanced with a call to
+   * CleanUpAfterNativeAppModalDialog once the app modal dialog is closed.
+   */
+  static bool PrepareForNativeAppModalDialog();
   static void CleanUpAfterNativeAppModalDialog();
 
   // 3 utility functions to go from a frame of imgIContainer to CGImage and then
diff --git a/widget/cocoa/nsCocoaUtils.mm b/widget/cocoa/nsCocoaUtils.mm
@@ -324,21 +324,32 @@ BOOL nsCocoaUtils::ShouldRestoreStateDueToLaunchAtLogin() {
   return NO;
 }
 
-void nsCocoaUtils::PrepareForNativeAppModalDialog() {
-  NS_OBJC_BEGIN_TRY_IGNORE_BLOCK;
+static bool sIsActivelyShowingAppModalDialog = false;
+
+bool nsCocoaUtils::PrepareForNativeAppModalDialog() {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (sIsActivelyShowingAppModalDialog) {
+    return false;
+  }
+  sIsActivelyShowingAppModalDialog = true;
 
   if (!NSApp.active) {
     // Early exit if the app isn't active. This is because we can't safely
     // set the NSApp.mainMenu property in such a case. We early exit so we
     // also don't invoke any side effects.
-    return;
+    return true;
   }
 
   // Don't do anything if this is embedding. We'll assume that if there is no
   // hidden window we shouldn't do anything, and that should cover the embedding
   // case.
   nsMenuBarX* hiddenWindowMenuBar = nsMenuUtilsX::GetHiddenWindowMenuBar();
-  if (!hiddenWindowMenuBar) return;
+  if (!hiddenWindowMenuBar) {
+    return true;
+  }
 
   // First put up the hidden window menu bar so that app menu event handling is
   // correct.
@@ -366,12 +377,20 @@ void nsCocoaUtils::PrepareForNativeAppModalDialog() {
   [NSApp setMainMenu:newMenuBar];
   [newMenuBar release];
 
-  NS_OBJC_END_TRY_IGNORE_BLOCK;
+  return true;
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(sIsActivelyShowingAppModalDialog = false);
 }
 
 void nsCocoaUtils::CleanUpAfterNativeAppModalDialog() {
   NS_OBJC_BEGIN_TRY_IGNORE_BLOCK;
 
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!sIsActivelyShowingAppModalDialog) {
+    return;
+  }
+
   // Don't do anything if this is embedding. We'll assume that if there is no
   // hidden window we shouldn't do anything, and that should cover the embedding
   // case.
@@ -387,6 +406,8 @@ void nsCocoaUtils::CleanUpAfterNativeAppModalDialog() {
     [WindowDelegate paintMenubarForWindow:mainWindow];
   }
 
+  sIsActivelyShowingAppModalDialog = false;
+
   NS_OBJC_END_TRY_IGNORE_BLOCK;
 }
 
diff --git a/widget/cocoa/nsFilePicker.mm b/widget/cocoa/nsFilePicker.mm
@@ -375,7 +375,9 @@ nsIFilePicker::ResultCode nsFilePicker::GetLocalFiles(
   }
 
   int result;
-  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  if (!nsCocoaUtils::PrepareForNativeAppModalDialog()) {
+    return retVal;
+  }
   if (mFilters.Length() > 1) {
     // [NSURL initWithString:] (below) throws an exception if URLString is nil.
 
@@ -469,7 +471,9 @@ nsIFilePicker::ResultCode nsFilePicker::GetLocalFolder(nsIFile** outFile) {
   if (theDir) {
     [thePanel setDirectoryURL:[NSURL fileURLWithPath:theDir isDirectory:YES]];
   }
-  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  if (!nsCocoaUtils::PrepareForNativeAppModalDialog()) {
+    return retVal;
+  }
   int result = [thePanel runModal];
   nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
 
@@ -554,7 +558,9 @@ nsIFilePicker::ResultCode nsFilePicker::PutLocalFile(nsIFile** outFile) {
   }
 
   // load the panel
-  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  if (!nsCocoaUtils::PrepareForNativeAppModalDialog()) {
+    return retVal;
+  }
   [thePanel setNameFieldStringValue:defaultFilename];
   int result = [thePanel runModal];
   nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
diff --git a/widget/cocoa/nsPrintDialogX.mm b/widget/cocoa/nsPrintDialogX.mm
@@ -134,7 +134,9 @@ nsPrintDialogServiceX::ShowPrintDialog(mozIDOMWindowProxy* aParent,
   [viewController release];
 
   // Show the dialog.
-  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  if (!nsCocoaUtils::PrepareForNativeAppModalDialog()) {
+    return NS_ERROR_FAILURE;
+  }
   int button = [panel runModal];
   nsCocoaUtils::CleanUpAfterNativeAppModalDialog();