Index: base/threading/simple_thread.h |
=================================================================== |
--- base/threading/simple_thread.h (revision 0) |
+++ base/threading/simple_thread.h (revision 0) |
@@ -0,0 +1,182 @@ |
+// Copyright (c) 2010 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+// WARNING: You should probably be using Thread (thread.h) instead. Thread is |
+// Chrome's message-loop based Thread abstraction, and if you are a |
+// thread running in the browser, there will likely be assumptions |
+// that your thread will have an associated message loop. |
+// |
+// This is a simple thread interface that backs to a native operating system |
+// thread. You should use this only when you want a thread that does not have |
+// an associated MessageLoop. Unittesting is the best example of this. |
+// |
+// The simplest interface to use is DelegateSimpleThread, which will create |
+// a new thread, and execute the Delegate's virtual Run() in this new thread |
+// until it has completed, exiting the thread. |
+// |
+// NOTE: You *MUST* call Join on the thread to clean up the underlying thread |
+// resources. You are also responsible for destructing the SimpleThread object. |
+// It is invalid to destroy a SimpleThread while it is running, or without |
+// Start() having been called (and a thread never created). The Delegate |
+// object should live as long as a DelegateSimpleThread. |
+// |
+// Thread Safety: A SimpleThread is not completely thread safe. It is safe to |
+// access it from the creating thread or from the newly created thread. This |
+// implies that the creator thread should be the thread that calls Join. |
+// |
+// Example: |
+// class MyThreadRunner : public DelegateSimpleThread::Delegate { ... }; |
+// MyThreadRunner runner; |
+// DelegateSimpleThread thread(&runner, "good_name_here"); |
+// thread.Start(); |
+// // Start will return after the Thread has been successfully started and |
+// // initialized. The newly created thread will invoke runner->Run(), and |
+// // run until it returns. |
+// thread.Join(); // Wait until the thread has exited. You *MUST* Join! |
+// // The SimpleThread object is still valid, however you may not call Join |
+// // or Start again. |
+ |
+#ifndef BASE_THREADING_SIMPLE_THREAD_H_ |
+#define BASE_THREADING_SIMPLE_THREAD_H_ |
+#pragma once |
+ |
+#include <string> |
+#include <queue> |
+#include <vector> |
+ |
+#include "base/basictypes.h" |
+#include "base/lock.h" |
+#include "base/waitable_event.h" |
+#include "base/platform_thread.h" |
+ |
+namespace base { |
+ |
+// This is the base SimpleThread. You can derive from it and implement the |
+// virtual Run method, or you can use the DelegateSimpleThread interface. |
+class SimpleThread : public PlatformThread::Delegate { |
+ public: |
+ class Options { |
+ public: |
+ Options() : stack_size_(0) { } |
+ ~Options() { } |
+ |
+ // We use the standard compiler-supplied copy constructor. |
+ |
+ // A custom stack size, or 0 for the system default. |
+ void set_stack_size(size_t size) { stack_size_ = size; } |
+ size_t stack_size() const { return stack_size_; } |
+ private: |
+ size_t stack_size_; |
+ }; |
+ |
+ // Create a SimpleThread. |options| should be used to manage any specific |
+ // configuration involving the thread creation and management. |
+ // Every thread has a name, in the form of |name_prefix|/TID, for example |
+ // "my_thread/321". The thread will not be created until Start() is called. |
+ explicit SimpleThread(const std::string& name_prefix); |
+ SimpleThread(const std::string& name_prefix, const Options& options); |
+ |
+ virtual ~SimpleThread(); |
+ |
+ virtual void Start(); |
+ virtual void Join(); |
+ |
+ // We follow the PlatformThread Delegate interface. |
+ virtual void ThreadMain(); |
+ |
+ // Subclasses should override the Run method. |
+ virtual void Run() = 0; |
+ |
+ // Return the thread name prefix, or "unnamed" if none was supplied. |
+ std::string name_prefix() { return name_prefix_; } |
+ |
+ // Return the completed name including TID, only valid after Start(). |
+ std::string name() { return name_; } |
+ |
+ // Return the thread id, only valid after Start(). |
+ PlatformThreadId tid() { return tid_; } |
+ |
+ // Return True if Start() has ever been called. |
+ bool HasBeenStarted() { return event_.IsSignaled(); } |
+ |
+ // Return True if Join() has evern been called. |
+ bool HasBeenJoined() { return joined_; } |
+ |
+ private: |
+ const std::string name_prefix_; |
+ std::string name_; |
+ const Options options_; |
+ PlatformThreadHandle thread_; // PlatformThread handle, invalid after Join! |
+ WaitableEvent event_; // Signaled if Start() was ever called. |
+ PlatformThreadId tid_; // The backing thread's id. |
+ bool joined_; // True if Join has been called. |
+}; |
+ |
+class DelegateSimpleThread : public SimpleThread { |
+ public: |
+ class Delegate { |
+ public: |
+ Delegate() { } |
+ virtual ~Delegate() { } |
+ virtual void Run() = 0; |
+ }; |
+ |
+ DelegateSimpleThread(Delegate* delegate, |
+ const std::string& name_prefix); |
+ DelegateSimpleThread(Delegate* delegate, |
+ const std::string& name_prefix, |
+ const Options& options); |
+ |
+ virtual ~DelegateSimpleThread(); |
+ virtual void Run(); |
+ private: |
+ Delegate* delegate_; |
+}; |
+ |
+// DelegateSimpleThreadPool allows you to start up a fixed number of threads, |
+// and then add jobs which will be dispatched to the threads. This is |
+// convenient when you have a lot of small work that you want done |
+// multi-threaded, but don't want to spawn a thread for each small bit of work. |
+// |
+// You just call AddWork() to add a delegate to the list of work to be done. |
+// JoinAll() will make sure that all outstanding work is processed, and wait |
+// for everything to finish. You can reuse a pool, so you can call Start() |
+// again after you've called JoinAll(). |
+class DelegateSimpleThreadPool : public DelegateSimpleThread::Delegate { |
+ public: |
+ typedef DelegateSimpleThread::Delegate Delegate; |
+ |
+ DelegateSimpleThreadPool(const std::string& name_prefix, int num_threads); |
+ virtual ~DelegateSimpleThreadPool(); |
+ |
+ // Start up all of the underlying threads, and start processing work if we |
+ // have any. |
+ void Start(); |
+ |
+ // Make sure all outstanding work is finished, and wait for and destroy all |
+ // of the underlying threads in the pool. |
+ void JoinAll(); |
+ |
+ // It is safe to AddWork() any time, before or after Start(). |
+ // Delegate* should always be a valid pointer, NULL is reserved internally. |
+ void AddWork(Delegate* work, int repeat_count); |
+ void AddWork(Delegate* work) { |
+ AddWork(work, 1); |
+ } |
+ |
+ // We implement the Delegate interface, for running our internal threads. |
+ virtual void Run(); |
+ |
+ private: |
+ const std::string name_prefix_; |
+ int num_threads_; |
+ std::vector<DelegateSimpleThread*> threads_; |
+ std::queue<Delegate*> delegates_; |
+ Lock lock_; // Locks delegates_ |
+ WaitableEvent dry_; // Not signaled when there is no work to do. |
+}; |
+ |
+} // namespace base |
+ |
+#endif // BASE_THREADING_SIMPLE_THREAD_H_ |
Property changes on: base/threading/simple_thread.h |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |