[platform] Implement a worker pool

test/cctest/test-libplatform.h

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef TEST_LIBPLATFORM_H_
+#define TEST_LIBPLATFORM_H_
+
+#include "v8.h"
+
+#include "cctest.h"
+
+using namespace v8::internal;
+
+class TaskCounter {
+ public:
+  TaskCounter() : counter_(0) {}
+  ~TaskCounter() { CHECK_EQ(0, counter_); }
+
+  int GetCount() const {
+    LockGuard<Mutex> guard(&lock_);
+    return counter_;
+  }
+
+  void Inc() {
+    LockGuard<Mutex> guard(&lock_);
+    ++counter_;
+  }
+
+  void Dec() {
+    LockGuard<Mutex> guard(&lock_);
+    --counter_;
+  }
+
+ private:
+  mutable Mutex lock_;
+  int counter_;
+
+  DISALLOW_COPY_AND_ASSIGN(TaskCounter);
+};
+
+
+class TestTask : public v8::Task {
+ public:
+  TestTask(TaskCounter* task_counter, bool expected_to_run)
+      : task_counter_(task_counter),
+        expected_to_run_(expected_to_run),
+        executed_(false) {
+    task_counter_->Inc();
+  }
+
+  explicit TestTask(TaskCounter* task_counter)
+      : task_counter_(task_counter), expected_to_run_(false), executed_(false) {
+    task_counter_->Inc();
+  }
+
+  virtual ~TestTask() {
+    CHECK_EQ(expected_to_run_, executed_);
+    task_counter_->Dec();
+  }
+
+  // v8::Task implementation.
+  virtual void Run() V8_OVERRIDE { executed_ = true; }
+
+ private:
+  TaskCounter* task_counter_;
+  bool expected_to_run_;
+  bool executed_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestTask);
+};
+
+
+class TestWorkerThread : public Thread {
+ public:
+  explicit TestWorkerThread(v8::Task* task)
+      : Thread("libplatform TestWorkerThread"), semaphore_(0), task_(task) {}
+  virtual ~TestWorkerThread() {}
+
+  void Signal() { semaphore_.Signal(); }
+
+  // Thread implementation.
+  virtual void Run() V8_OVERRIDE {
+    semaphore_.Wait();
+    if (task_) {
+      task_->Run();
+      delete task_;
+    }
+  }
+
+ private:
+  Semaphore semaphore_;
+  v8::Task* task_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestWorkerThread);
+};
+
+#endif  // TEST_LIBPLATFORM_H_