Add an API to pump the message loop to libplatform

src/libplatform/default-platform.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/libplatform/default-platform.h"
 
 #include <algorithm>
 #include <queue>
 
 #include "src/base/logging.h"
 #include "src/base/platform/platform.h"
 #include "src/libplatform/worker-thread.h"
 
 namespace v8 {
 namespace platform {
 
 
 v8::Platform* CreateDefaultPlatform(int thread_pool_size) {
   DefaultPlatform* platform = new DefaultPlatform();
   platform->SetThreadPoolSize(thread_pool_size);
   platform->EnsureInitialized();
   return platform;
 }
 
 
+bool PumpMessageLoop(v8::Platform* platform, v8::Isolate* isolate) {
+  return reinterpret_cast<DefaultPlatform*>(platform)->PumpMessageLoop(isolate);
+}
+
+
 const int DefaultPlatform::kMaxThreadPoolSize = 4;
 
 
 DefaultPlatform::DefaultPlatform()
     : initialized_(false), thread_pool_size_(0) {}
 
 
 DefaultPlatform::~DefaultPlatform() {
   base::LockGuard<base::Mutex> guard(&lock_);
   queue_.Terminate();
   if (initialized_) {
     for (std::vector<WorkerThread*>::iterator i = thread_pool_.begin();
          i != thread_pool_.end(); ++i) {
       delete *i;
     }
   }
+  for (std::map<v8::Isolate*, std::queue<Task*> >::iterator i =
+           main_thread_queue_.begin();
+       i != main_thread_queue_.end(); ++i) {
+    while (!i->second.empty()) {
+      delete i->second.front();
+      i->second.pop();
+    }
+  }
 }
 
 
 void DefaultPlatform::SetThreadPoolSize(int thread_pool_size) {
   base::LockGuard<base::Mutex> guard(&lock_);
   ASSERT(thread_pool_size >= 0);
   if (thread_pool_size < 1)
     thread_pool_size = base::OS::NumberOfProcessorsOnline();
   thread_pool_size_ =
       std::max(std::min(thread_pool_size, kMaxThreadPoolSize), 1);
 }
 
 
 void DefaultPlatform::EnsureInitialized() {
   base::LockGuard<base::Mutex> guard(&lock_);
   if (initialized_) return;
   initialized_ = true;
 
   for (int i = 0; i < thread_pool_size_; ++i)
     thread_pool_.push_back(new WorkerThread(&queue_));
 }
 
+
+bool DefaultPlatform::PumpMessageLoop(v8::Isolate* isolate) {
+  Task* task = NULL;
+  {
+    base::LockGuard<base::Mutex> guard(&lock_);
+    std::map<v8::Isolate*, std::queue<Task*> >::iterator it =
+        main_thread_queue_.find(isolate);
+    if (it == main_thread_queue_.end() || it->second.empty()) {
+      return false;
+    }
+    task = it->second.front();
+    it->second.pop();
+  }
+  task->Run();
+  delete task;
+  return true;
+}
+
 void DefaultPlatform::CallOnBackgroundThread(Task *task,
                                              ExpectedRuntime expected_runtime) {
   EnsureInitialized();
   queue_.Append(task);
 }
 
 
 void DefaultPlatform::CallOnForegroundThread(v8::Isolate* isolate, Task* task) {
-  // TODO(jochen): implement.
-  task->Run();
-  delete task;
+  base::LockGuard<base::Mutex> guard(&lock_);
+  main_thread_queue_[isolate].push(task);
 }
 
 } }  // namespace v8::platform