Add vmservice_dartium.dart script

runtime/bin/vmservice/vmservice_dartium.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.
+
+library vmservice_dartium;
+
+import 'dart:isolate';
+import 'vmservice.dart';
+
+// The receive port that isolate startup / shutdown messages are delivered on.
+RawReceivePort _receivePort;
+// The receive port that service request messages are delivered on.
+RawReceivePort _requestPort;
+
+// The native method that is called to post the response back to DevTools.
+void postResponse(String response, int cookie) native "PostResponse";

[siva, 2013/12/06 00:04:18]

Can the name PostResponse be qualified as
"vmservice_PostResponse" or something like that, that would be in line with
native methods in other files:

e.g:
  Node get firstChild native "Node_firstChild_Getter";
in class Node {
   ....
}

[Cutch, 2013/12/06 01:36:08]

Agreed. I'm doing this in a cleanup CL that I will CC you on.

+
+void handleRequest(service, String uri, cookie) {
+  var serviceRequest = new ServiceRequest();
+  var r = serviceRequest.parse(Uri.parse(uri));
+  if (!r) {
+    // Did not understand the request uri.
+    serviceRequest.setErrorResponse('Invalid request uri: ${uri}');
+  } else {
+    var f = service.runningIsolates.route(serviceRequest);
+    if (f != null) {
+      f.then((_) {
+        postResponse(serviceRequest.response, cookie);
+      }).catchError((e) { });

[siva, 2013/12/06 00:04:18]

should the catchError case also post an error response?

[Cutch, 2013/12/06 01:36:08]

The only way for catchError to trigger would be if the call to the native method
resulted in an error. At that point we can't send an error response.

+      return;
+    } else {
+      // Nothing responds to this type of request.
+      serviceRequest.setErrorResponse('No route for: $uri');
+    }
+  }
+  postResponse(serviceRequest.response, cookie);
+}
+
+main() {
+  // Create VmService.
+  var service = new VMService();
+  _receivePort = service.receivePort;
+  _requestPort = new RawReceivePort((message) {
+    if (message == null) {
+      return;
+    }
+    if (message is! List) {
+      return;
+    }
+    if (message.length != 2) {
+      return;
+    }
+    var uri = message[0];
+    if (uri is! String) {
+      return;
+    }

[siva, 2013/12/06 00:04:18]

In the above code we seem to ignore invalid messages but in handleRequest we
post an Error response when we get an invalid request, why this divergence?

[Cutch, 2013/12/06 01:36:08]

This code is verifying that the data from the embedder is valid. We error check
on the embedder side as well. We could probably get rid of these checks.

+    var cookie = message[1];
+    handleRequest(service, uri, cookie);
+  });
+}