blob: e65acca2a5eb6101db58724e1df879fa56790eb9 [file] [log] [blame]
// Copyright (c) 2013 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.
#include "base/bind.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "ppapi/shared_impl/ppapi_shared_export.h"
#include "ppapi/shared_impl/proxy_lock.h"
namespace ppapi {
class MessageLoopShared;
namespace internal {
class PPAPI_SHARED_EXPORT ThreadAwareCallbackBase {
static bool HasTargetLoop();
void InternalRunOnTargetThread(const base::Closure& closure);
class Core;
scoped_refptr<MessageLoopShared> target_loop_;
scoped_refptr<Core> core_;
} // namespace internal
// Some PPB interfaces have methods that set a custom callback. Usually, the
// callback has to be called on the same thread as the one it was set on.
// ThreadAwareCallback keeps track of the target thread, and posts a task to run
// on it if requested from a different thread.
// Please note that:
// - Unlike TrackedCallback, there is no restriction on how many times the
// callback will be called.
// - When a ThreadAwareCallback object is destroyed, all pending tasks to run
// the callback will be ignored. It is designed this way so that when the
// resource is destroyed or the callback is cancelled by the plugin, we can
// simply delete the ThreadAwareCallback object to prevent touching the
// callback later.
// - When RunOnTargetThread() is called on the target thread, the callback runs
// immediately.
template <class FuncType>
class ThreadAwareCallback : public internal::ThreadAwareCallbackBase {
// The caller takes ownership of the returned object.
// NULL is returned if the current thread doesn't have an associated Pepper
// message loop, or |func| is NULL.
static ThreadAwareCallback* Create(FuncType func) {
if (!func || !HasTargetLoop())
return NULL;
return new ThreadAwareCallback(func);
~ThreadAwareCallback() {}
void RunOnTargetThread() { InternalRunOnTargetThread(base::Bind(func_)); }
template <class P1>
void RunOnTargetThread(const P1& p1) {
InternalRunOnTargetThread(base::Bind(func_, p1));
template <class P1, class P2>
void RunOnTargetThread(const P1& p1, const P2& p2) {
InternalRunOnTargetThread(base::Bind(func_, p1, p2));
template <class P1, class P2, class P3>
void RunOnTargetThread(const P1& p1, const P2& p2, const P3& p3) {
InternalRunOnTargetThread(base::Bind(func_, p1, p2, p3));
template <class P1, class P2, class P3, class P4>
void RunOnTargetThread(const P1& p1,
const P2& p2,
const P3& p3,
const P4& p4) {
InternalRunOnTargetThread(base::Bind(func_, p1, p2, p3, p4));
template <class P1, class P2, class P3, class P4, class P5>
void RunOnTargetThread(const P1& p1,
const P2& p2,
const P3& p3,
const P4& p4,
const P5& p5) {
InternalRunOnTargetThread(base::Bind(func_, p1, p2, p3, p4, p5));
explicit ThreadAwareCallback(FuncType func) : func_(func) {}
FuncType func_;
} // namespace ppapi