blob: 2010492f71921a4125f7c3beb27b12a7304cf436 [file] [log] [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BASE_MESSAGE_LOOP_MESSAGE_PUMP_ANDROID_H_
#define BASE_MESSAGE_LOOP_MESSAGE_PUMP_ANDROID_H_
#include <jni.h>
#include <optional>
#include "base/base_export.h"
#include "base/functional/callback.h"
#include "base/memory/raw_ptr.h"
#include "base/message_loop/message_pump.h"
#include "base/time/time.h"
struct ALooper;
namespace base {
class RunLoop;
// This class implements a MessagePump needed for MessagePumpType::UI and
// MessagePumpType::JAVA MessageLoops on OS_ANDROID platform.
//
// It works by registering two file descriptors for the Looper to additionally
// poll: one for delayed work and one for non-delayed work. For queueing
// immediate work within the Looper it writes to the eventfd(2). For delayed
// work it performs timerfd_settime(2).
//
// See: https://developer.android.com/ndk/reference/group/looper.
class BASE_EXPORT MessagePumpAndroid : public MessagePump {
public:
MessagePumpAndroid();
MessagePumpAndroid(const MessagePumpAndroid&) = delete;
MessagePumpAndroid& operator=(const MessagePumpAndroid&) = delete;
~MessagePumpAndroid() override;
void Run(Delegate* delegate) override;
void Quit() override;
void ScheduleWork() override;
void ScheduleDelayedWork(
const Delegate::NextWorkInfo& next_work_info) override;
static void InitializeFeatures();
// Attaches |delegate| to this native MessagePump. |delegate| will from then
// on be invoked by the native loop to process application tasks.
virtual void Attach(Delegate* delegate);
// We call Abort when there is a pending JNI exception, meaning that the
// current thread will crash when we return to Java.
// We can't call any JNI-methods before returning to Java as we would then
// cause a native crash (instead of the original Java crash).
void Abort() { should_abort_ = true; }
bool IsAborted() { return should_abort_; }
bool ShouldQuit() const { return should_abort_ || quit_; }
// Tells the RunLoop to quit when idle, calling the callback when it's safe
// for the Thread to stop.
void QuitWhenIdle(base::OnceClosure callback);
// These functions are only public so that the looper callbacks can call them,
// and should not be called from outside this class.
void OnDelayedLooperCallback();
virtual void OnNonDelayedLooperCallback(); // Overridden for testing.
void set_is_type_ui(bool is_type_ui) { is_type_ui_ = is_type_ui; }
protected:
Delegate* SetDelegate(Delegate* delegate);
bool SetQuit(bool quit);
virtual void DoDelayedLooperWork();
virtual void DoNonDelayedLooperWork(bool do_idle_work);
private:
void ScheduleWorkInternal(bool do_idle_work);
void DoIdleWork();
// Unlike other platforms, we don't control the message loop as it's
// controlled by the Android Looper, so we can't run a RunLoop to keep the
// Thread this pump belongs to alive. However, threads are expected to have an
// active run loop, so we manage a RunLoop internally here, starting/stopping
// it as necessary.
std::unique_ptr<RunLoop> run_loop_;
// See Abort().
bool should_abort_ = false;
// Whether this message pump is quitting, or has quit.
bool quit_ = false;
// The MessageLoop::Delegate for this pump.
raw_ptr<Delegate> delegate_ = nullptr;
// The time at which we are currently scheduled to wake up and perform a
// delayed task. This avoids redundantly scheduling |delayed_fd_| with the
// same timeout when subsequent work phases all go idle on the same pending
// delayed task; nullopt if no wakeup is currently scheduled.
std::optional<TimeTicks> delayed_scheduled_time_;
// If set, a callback to fire when the message pump is quit.
base::OnceClosure on_quit_callback_;
// The file descriptor used to signal that non-delayed work is available.
int non_delayed_fd_;
// The file descriptor used to signal that delayed work is available.
int delayed_fd_;
// The Android Looper for this thread.
raw_ptr<ALooper> looper_ = nullptr;
// The JNIEnv* for this thread, used to check for pending exceptions.
raw_ptr<JNIEnv> env_;
// Whether this message serves a MessagePumpType::UI, and therefore can
// consult with the input hint living on the UI thread.
bool is_type_ui_ = false;
};
} // namespace base
#endif // BASE_MESSAGE_LOOP_MESSAGE_PUMP_ANDROID_H_