Merge pull request #89 from vibe-d/fix_waitfordataasync_scoped_destruction

Fix waitForDataAsync compilation error for callbacks that have scoped…
merged-on-behalf-of: Leonid Kramer <l-kramer@users.noreply.github.com>

source/vibe/core/net.d

@@ -619,7 +619,7 @@ mixin(tracer);
 		if (is(typeof(() @safe { read_ready_callback(true); } ())))
 	{
 mixin(tracer);
-		import vibe.core.core : setTimer;
+		import vibe.core.core : Timer, setTimer;
 
 		if (!m_context)
 			return WaitForDataAsyncStatus.noMoreData;
@@ -632,17 +632,49 @@ mixin(tracer);
 			return rs ? WaitForDataAsyncStatus.dataAvailable : WaitForDataAsyncStatus.noMoreData;
 		}
 
-		auto tm = setTimer(timeout, {
-			eventDriver.sockets.cancelRead(m_socket);
-			read_ready_callback(false);
-		});
-		eventDriver.sockets.read(m_socket, m_context.readBuffer.peekDst(), IOMode.once,
-			(sock, st, nb) {
-				tm.stop();
-				assert(m_context.readBuffer.length == 0);
-				m_context.readBuffer.putN(nb);
-				read_ready_callback(m_context.readBuffer.length > 0);
-			});
+		static final class WaitContext {
+			import std.algorithm.mutation : move;
+
+			CALLABLE callback;
+			TCPConnection connection;
+			Timer timer;
+
+			this(CALLABLE callback, TCPConnection connection, Duration timeout)
+			{
+				this.callback = callback;
+				this.connection = connection;
+				if (timeout < Duration.max)
+					this.timer = setTimer(timeout, &onTimeout);
+			}
+
+			void onTimeout()
+			{
+				eventDriver.sockets.cancelRead(connection.m_socket);
+				invoke(false);
+			}
+
+			void onData(StreamSocketFD, IOStatus st, size_t nb)
+			{
+				if (timer) timer.stop();
+				assert(connection.m_context.readBuffer.length == 0);
+				connection.m_context.readBuffer.putN(nb);
+				invoke(connection.m_context.readBuffer.length > 0);
+			}
+
+			void invoke(bool status)
+			{
+				auto cb = move(callback);
+				connection = TCPConnection.init;
+				timer = Timer.init;
+				cb(status);
+			}
+		}
+
+		// FIXME: make this work without a heap allocation!
+		auto context = new WaitContext(read_ready_callback, this, timeout);
+
+		eventDriver.sockets.read(m_socket, m_context.readBuffer.peekDst(),
+			IOMode.once, &context.onData);
 
 		return WaitForDataAsyncStatus.waiting;
 	}
@@ -758,6 +790,20 @@ enum WaitForDataAsyncStatus {
 	waiting,
 }
 
+unittest { // test compilation of callback with scoped destruction
+	static struct CB {
+		~this() {}
+		this(this) {}
+		void opCall(bool) {}
+	}
+
+	void test() {
+		TCPConnection c;
+		CB cb;
+		c.waitForDataAsync(cb);
+	}
+}
+
 
 mixin validateConnectionStream!TCPConnection;
 
@@ -1066,4 +1112,4 @@ class ReadTimeoutException: Exception
 	{
 		super(message, file, line, next);
 	}
-}
+}