webrtc_m130/webrtc/modules/desktop_capture/screen_capture_frame_queue.h
sergeyu b4c7b8365d Revert of Use std::unique_ptr<> to pass frame ownership in DesktopCapturer impls. (patchset #7 id:140001 of https://codereview.webrtc.org/1988783003/ )
Reason for revert:
Broke chromium builder

Original issue's description:
> Use std::unique_ptr<> to pass frame ownership in DesktopCapturer impls.
>
> Previously raw pointers were used for owned DesktopFrame instances.
> Updated all screen and window capturer implementations to use
> std::unique_ptr<>.
>
> Also includes some other cleanups in the capturers:
>  - s/NULL/nullptr
>  - moved default initializers to class definition.
>
> BUG=webrtc:5950
>
> Committed: https://crrev.com/4a627a8c13554d12412cabb8f751caee6e61ee32
> Cr-Commit-Position: refs/heads/master@{#13032}

TBR=wez@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:5950

Review-Url: https://codereview.webrtc.org/2030333003
Cr-Commit-Position: refs/heads/master@{#13033}
2016-06-03 12:56:47 +00:00

86 lines
3.0 KiB
C++

/*
* Copyright (c) 2013 The WebRTC 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 in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURE_FRAME_QUEUE_H_
#define WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURE_FRAME_QUEUE_H_
#include <memory>
#include "webrtc/base/constructormagic.h"
// TODO(zijiehe): These headers are not used in this file, but to avoid build
// break in remoting/host. We should add headers in each individual files.
#include "webrtc/modules/desktop_capture/desktop_frame.h" // Remove
#include "webrtc/modules/desktop_capture/shared_desktop_frame.h" // Remove
namespace webrtc {
// Represents a queue of reusable video frames. Provides access to the 'current'
// frame - the frame that the caller is working with at the moment, and to the
// 'previous' frame - the predecessor of the current frame swapped by
// MoveToNextFrame() call, if any.
//
// The caller is expected to (re)allocate frames if current_frame() returns
// NULL. The caller can mark all frames in the queue for reallocation (when,
// say, frame dimensions change). The queue records which frames need updating
// which the caller can query.
//
// Frame consumer is expected to never hold more than kQueueLength frames
// created by this function and it should release the earliest one before trying
// to capture a new frame (i.e. before MoveToNextFrame() is called).
template <typename FrameType>
class ScreenCaptureFrameQueue {
public:
ScreenCaptureFrameQueue() : current_(0) {}
~ScreenCaptureFrameQueue() = default;
// Moves to the next frame in the queue, moving the 'current' frame to become
// the 'previous' one.
void MoveToNextFrame() {
current_ = (current_ + 1) % kQueueLength;
}
// Replaces the current frame with a new one allocated by the caller. The
// existing frame (if any) is destroyed. Takes ownership of |frame|.
void ReplaceCurrentFrame(FrameType* frame) {
frames_[current_].reset(frame);
}
// Marks all frames obsolete and resets the previous frame pointer. No
// frames are freed though as the caller can still access them.
void Reset() {
for (int i = 0; i < kQueueLength; i++) {
frames_[i].reset();
}
current_ = 0;
}
FrameType* current_frame() const {
return frames_[current_].get();
}
FrameType* previous_frame() const {
return frames_[(current_ + kQueueLength - 1) % kQueueLength].get();
}
private:
// Index of the current frame.
int current_;
static const int kQueueLength = 2;
std::unique_ptr<FrameType> frames_[kQueueLength];
RTC_DISALLOW_COPY_AND_ASSIGN(ScreenCaptureFrameQueue);
};
} // namespace webrtc
#endif // WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURE_FRAME_QUEUE_H_