Make event-handlers edge-triggered and move socket-state to Dart.

sdk/lib/io/secure_socket.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 /**
  * A high-level class for communicating securely over a TCP socket, using
  * TLS and SSL. The [SecureSocket] exposes both a [Stream] and an
  * [IOSink] interface, making it ideal for using together with
@@ skipping 955 matching lines @@
         _pauseCount == 0 &&
         _secureFilter != null &&
         !_secureFilter.buffers[READ_PLAINTEXT].isEmpty) {
       _pendingReadEvent = true;
       Timer.run(_sendReadEvent);
     }
   }
 
   _sendReadEvent() {
     _pendingReadEvent = false;
-    if (_readEventsEnabled &&
+    if (_status != CLOSED &&
+        _readEventsEnabled &&
         _pauseCount == 0 &&
         _secureFilter != null &&
         !_secureFilter.buffers[READ_PLAINTEXT].isEmpty) {
       _controller.add(RawSocketEvent.READ);
       _scheduleReadEvent();
     }
   }
 
   // If a write event should be sent, add it to the controller.
   _sendWriteEvent() {
@@ skipping 170 matching lines @@
       written += toWrite;
       toWrite = min(bytes - written, linearFree);
     }
     return written;
   }
 
   int writeFromSource(List<int> getData(int requested)) {
     int written = 0;
     int toWrite = linearFree;
     // Loop over zero, one, or two linear data ranges.
-    while (toWrite > 0) {
+    do {
       // Source returns at most toWrite bytes, and it returns null when empty.
       var inputData = getData(toWrite);
-      if (inputData == null) break;
+      if (inputData == null || inputData.length == 0) break;
       var len = inputData.length;
       data.setRange(end, end + len, inputData);
       advanceEnd(len);
       written += len;
       toWrite = linearFree;
-    }
+    } while (toWrite > 0);
     return written;
   }
 
   bool readToSocket(RawSocket socket) {
     // Loop over zero, one, or two linear data ranges.
     while (true) {
       var toWrite = linearLength;
       if (toWrite == 0) return false;
       int bytes = socket.write(data, start, toWrite);
       advanceStart(bytes);
@@ skipping 77 matching lines @@
 /**
  * An exception that happens in the handshake phase of establishing
  * a secure network connection, when looking up or verifying a
  * certificate.
  */
 class CertificateException extends TlsException {
   const CertificateException([String message = "",
                             OSError osError = null])
      : super._("CertificateException", message, osError);
 }