Call Swift connection close callback from global executor

.gitignore

@@ -111,13 +111,6 @@ csharp/AppX
 cpp/AppX
 cpp/test/Slice/errorDetection/tmp
 
-Carthage
-
-# iOS builds
-
-**/objs-*/
-**/build-*/
-
 .classpath
 .project
 .settings

swift/src/Ice/Connection.swift

@@ -141,13 +141,13 @@ public protocol ConnectionInfo: AnyObject {
     var connectionId: String { get set }
 }
 
-/// An application can implement this interface to receive notifications when a connection closes.
+/// An application can register a callback to be notified when a connection is closed.
 ///
 /// This method is called by the connection when the connection is closed. If the callback needs more information
 /// about the closure, it can call Connection.throwException.
 ///
 /// - parameter _: `Connection?` The connection that closed.
-public typealias CloseCallback = (Connection?) -> Void
+public typealias CloseCallback = (Connection?) async -> Void
 
 /// The user-level interface to a connection.
 public protocol Connection: AnyObject, CustomStringConvertible {
@@ -195,9 +195,8 @@ public protocol Connection: AnyObject, CustomStringConvertible {
         _ compress: CompressBatch
     ) async throws
 
-    /// Set a close callback on the connection. The callback is called by the connection when it's closed. The callback
-    /// is called from the Ice thread pool associated with the connection. If the callback needs more information about
-    /// the closure, it can call Connection.throwException.
+    /// Set a close callback on the connection. The callback is called (on the global executor) by the connection when
+    /// it's closed. If the callback needs more information about the closure, it can call Connection.throwException.
     ///
     /// - parameter _: `CloseCallback?` The close callback object.
     func setCloseCallback(_ callback: CloseCallback?) throws

swift/src/Ice/ConnectionI.swift

@@ -66,7 +66,9 @@ class ConnectionI: LocalObject<ICEConnection>, Connection {
 
             try handle.setCloseCallback { c in
                 precondition(c.getCachedSwiftObject(ConnectionI.self) === self)
-                cb(self)
+                Task {
+                    await cb(self)
+                }
             }
         }
     }

swift/src/IceImpl/Connection.mm

@@ -89,11 +89,7 @@ - (BOOL)setCloseCallback:(void (^)(ICEConnection*))callback error:(NSError**)err
 {
     try
     {
-        if (!callback)
-        {
-            self.connection->setCloseCallback(nullptr);
-        }
-        else
+        if (callback)
         {
             self.connection->setCloseCallback(
                 [callback](auto connection)
@@ -106,6 +102,10 @@ - (BOOL)setCloseCallback:(void (^)(ICEConnection*))callback error:(NSError**)err
                     }
                 });
         }
+        else
+        {
+            self.connection->setCloseCallback(nullptr);
+        }
         return YES;
     }
     catch (...)