Allow embedders to provide custom message delivery for an isolate.

runtime/vm/message_queue.h

 // Copyright (c) 2011, 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.
 
-#ifndef VM_PORT_H_
-#define VM_PORT_H_
+#ifndef VM_MESSAGE_QUEUE_H_
+#define VM_MESSAGE_QUEUE_H_
 
-#include "vm/allocation.h"
-#include "vm/globals.h"
-#include "vm/growable_array.h"
-#include "vm/isolate.h"
+#include "include/dart_api.h"
 #include "vm/thread.h"
 
 namespace dart {
 
 class PortMessage {
  public:
   // A new message to be sent between two isolates. The data handed to this
   // message will be disposed by calling free() once the message object is
   // being destructed (after delivery or when the receiving port is closed).
-  PortMessage(intptr_t dest_id, intptr_t reply_id, void* data)
+  PortMessage(Dart_Port dest_port, Dart_Port reply_port, Dart_Message data)
       : next_(NULL),
-        dest_id_(dest_id),
-        reply_id_(reply_id),
+        dest_port_(dest_port),
+        reply_port_(reply_port),
         data_(data) {}
   ~PortMessage() {
     free(data_);
   }
 
-  intptr_t dest_id() const { return dest_id_; }
-  intptr_t reply_id() const { return reply_id_; }
-  void* data() const { return data_; }
-
-  void Handle();
+  Dart_Port dest_port() const { return dest_port_; }
+  Dart_Port reply_port() const { return reply_port_; }
+  Dart_Message data() const { return data_; }
 
  private:
+  friend class MessageQueue;
+
   PortMessage* next_;
-  intptr_t dest_id_;
-  intptr_t reply_id_;
-  void* data_;
-
-  friend class MessageQueue;
+  Dart_Port dest_port_;
+  Dart_Port reply_port_;
+  Dart_Message data_;
 
   DISALLOW_COPY_AND_ASSIGN(PortMessage);
 };
 
 
-// There is a message queue per isolate. Access to the message queue should be
-// protected by the isolate monitor.
+// There is a message queue per isolate.
 class MessageQueue {
  public:
   MessageQueue() : head_(NULL), tail_(NULL) {}
   ~MessageQueue();
 
   void Enqueue(PortMessage* msg);
-  PortMessage* Dequeue();
 
-  void Flush(intptr_t id);
+  // May block if no message is available.
+  PortMessage* Dequeue(int64_t millis);
+
+  void Flush(Dart_Port port);
   void FlushAll();
 
  private:
+  friend class MessageQueueTestPeer;
+
+  Monitor monitor_;
   PortMessage* head_;
   PortMessage* tail_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageQueue);
 };
 
-
-class PortMap: public AllStatic {
- public:
-  // Allocate a port in the current isolate and return its VM-global id.
-  static intptr_t CreatePort();
-
-  // Close the port with id. All pending messages will be dropped.
-  static void ClosePort(intptr_t id);
-
-  // Close all the ports of the current isolate.
-  static void ClosePorts();
-
-  static bool IsActivePort(intptr_t id);
-
-  // Enqueues the message in the port with id. Returns false if the port is not
-  // active any longer.
-  static bool PostMessage(PortMessage* msg);
-
-  // Dequeue the next message pending for this isolate. Returns null if timeout
-  // was reached before a message was posted.
-  static PortMessage* ReceiveMessage(int64_t millis);
-
-  static void InitOnce();
-
- private:
-  // Mapping between port numbers and isolates.
-  // Free entries have id == 0 and isolate == NULL. Deleted entries have id == 0
-  // and isolate == deleted_entry_.
-  typedef struct {
-    intptr_t id;
-    Isolate* isolate;
-  } Entry;
-
-  // Allocate a new unique port id.
-  static intptr_t AllocateId();
-
-  static intptr_t FindId(intptr_t id);
-  static void Rehash(intptr_t new_capacity);
-
-  static void MaintainInvariants();
-
-  // Lock protecting access to the port map.
-  static Mutex* mutex_;
-
-  // Hashmap of ports.
-  static Entry* map_;
-  static Isolate* deleted_entry_;
-  static intptr_t capacity_;
-  static intptr_t used_;
-  static intptr_t deleted_;
-
-  static intptr_t next_id_;
-};
-
 }  // namespace dart
 
-#endif  // VM_PORT_H_
+#endif  // VM_MESSAGE_QUEUE_H_