Implement DesktopCapturerWrapper and CaptureResultDesktopCapturerWrapper
Wrapper pattern is widely used in DesktopCapturer implementations. So this
change adds DesktopCapturerWrapper and CaptureResultDesktopCapturerWrapper as
the base classes of other wrappers. Implementing a new wrapper should become
easy, the implementation does not need to care about the uninteresting
overrides.
Bug: chromium:764258
Change-Id: If91c1b5e778805906f7f77854ea5600aa61bf64a
Reviewed-on: https://webrtc-review.googlesource.com/1420
Commit-Queue: Zijie He <zijiehe@google.com>
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#19868}diff --git a/modules/desktop_capture/BUILD.gn b/modules/desktop_capture/BUILD.gn
index 75311bd..d08e69d 100644
--- a/modules/desktop_capture/BUILD.gn
+++ b/modules/desktop_capture/BUILD.gn
@@ -207,6 +207,8 @@
sources = [
"blank_detector_desktop_capturer_wrapper.cc",
"blank_detector_desktop_capturer_wrapper.h",
+ "capture_result_desktop_capturer_wrapper.cc",
+ "capture_result_desktop_capturer_wrapper.h",
"cropped_desktop_frame.cc",
"cropped_desktop_frame.h",
"cropping_window_capturer.cc",
@@ -220,6 +222,8 @@
"desktop_capturer.h",
"desktop_capturer_differ_wrapper.cc",
"desktop_capturer_differ_wrapper.h",
+ "desktop_capturer_wrapper.cc",
+ "desktop_capturer_wrapper.h",
"desktop_frame_rotation.cc",
"desktop_frame_rotation.h",
"desktop_frame_win.cc",
diff --git a/modules/desktop_capture/capture_result_desktop_capturer_wrapper.cc b/modules/desktop_capture/capture_result_desktop_capturer_wrapper.cc
new file mode 100644
index 0000000..b15ce2b
--- /dev/null
+++ b/modules/desktop_capture/capture_result_desktop_capturer_wrapper.cc
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2017 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.
+ */
+
+#include "modules/desktop_capture/capture_result_desktop_capturer_wrapper.h"
+
+#include <memory>
+#include <utility>
+
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+CaptureResultDesktopCapturerWrapper::CaptureResultDesktopCapturerWrapper(
+ std::unique_ptr<DesktopCapturer> base_capturer,
+ ResultObserver* observer)
+ : DesktopCapturerWrapper(std::move(base_capturer)),
+ observer_(observer) {
+ RTC_DCHECK(observer_);
+}
+
+CaptureResultDesktopCapturerWrapper::
+~CaptureResultDesktopCapturerWrapper() = default;
+
+void CaptureResultDesktopCapturerWrapper::Start(Callback* callback) {
+ if ((callback_ == nullptr) != (callback == nullptr)) {
+ if (callback) {
+ base_capturer_->Start(this);
+ } else {
+ base_capturer_->Start(nullptr);
+ }
+ }
+ callback_ = callback;
+}
+
+void CaptureResultDesktopCapturerWrapper::OnCaptureResult(
+ Result result,
+ std::unique_ptr<DesktopFrame> frame) {
+ observer_->Observe(&result, &frame);
+ callback_->OnCaptureResult(result, std::move(frame));
+}
+
+} // namespace webrtc
diff --git a/modules/desktop_capture/capture_result_desktop_capturer_wrapper.h b/modules/desktop_capture/capture_result_desktop_capturer_wrapper.h
new file mode 100644
index 0000000..3f97bc5
--- /dev/null
+++ b/modules/desktop_capture/capture_result_desktop_capturer_wrapper.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2017 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 MODULES_DESKTOP_CAPTURE_CAPTURE_RESULT_DESKTOP_CAPTURER_WRAPPER_H_
+#define MODULES_DESKTOP_CAPTURE_CAPTURE_RESULT_DESKTOP_CAPTURER_WRAPPER_H_
+
+#include <memory>
+
+#include "modules/desktop_capture/desktop_capturer.h"
+#include "modules/desktop_capture/desktop_capturer_wrapper.h"
+
+namespace webrtc {
+
+// A DesktopCapturerWrapper implementation to capture the result of
+// |base_capturer|. Derived classes are expected to provide a ResultObserver
+// implementation to observe the DesktopFrame returned by |base_capturer_|.
+class CaptureResultDesktopCapturerWrapper
+ : public DesktopCapturerWrapper,
+ public DesktopCapturer::Callback {
+ public:
+ using Callback = DesktopCapturer::Callback;
+
+ // Provides a way to let derived classes or clients to modify the result
+ // returned by |base_capturer_|.
+ class ResultObserver {
+ public:
+ ResultObserver();
+ virtual ~ResultObserver();
+
+ virtual void Observe(Result* result,
+ std::unique_ptr<DesktopFrame>* frame) = 0;
+ };
+
+ // |observer| must outlive this instance and can be |this|. |observer| is
+ // guaranteed to be executed only after the constructor and before the
+ // destructor.
+ CaptureResultDesktopCapturerWrapper(
+ std::unique_ptr<DesktopCapturer> base_capturer,
+ ResultObserver* observer);
+
+ ~CaptureResultDesktopCapturerWrapper() override;
+
+ // DesktopCapturer implementations.
+ void Start(Callback* callback) final;
+
+ private:
+ // DesktopCapturer::Callback implementation.
+ void OnCaptureResult(Result result,
+ std::unique_ptr<DesktopFrame> frame) final;
+
+ ResultObserver* const observer_;
+ Callback* callback_ = nullptr;
+};
+
+} // namespace webrtc
+
+#endif // MODULES_DESKTOP_CAPTURE_CAPTURE_RESULT_DESKTOP_CAPTURER_WRAPPER_H_
diff --git a/modules/desktop_capture/desktop_capturer_wrapper.cc b/modules/desktop_capture/desktop_capturer_wrapper.cc
new file mode 100644
index 0000000..4bbdd6c
--- /dev/null
+++ b/modules/desktop_capture/desktop_capturer_wrapper.cc
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2017 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.
+ */
+
+#include "modules/desktop_capture/desktop_capturer_wrapper.h"
+
+#include <utility>
+
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+DesktopCapturerWrapper::DesktopCapturerWrapper(
+ std::unique_ptr<DesktopCapturer> base_capturer)
+ : base_capturer_(std::move(base_capturer)) {
+ RTC_DCHECK(base_capturer_);
+}
+
+DesktopCapturerWrapper::~DesktopCapturerWrapper() = default;
+
+void DesktopCapturerWrapper::Start(Callback* callback) {
+ base_capturer_->Start(callback);
+}
+
+void DesktopCapturerWrapper::SetSharedMemoryFactory(
+ std::unique_ptr<SharedMemoryFactory> shared_memory_factory) {
+ base_capturer_->SetSharedMemoryFactory(std::move(shared_memory_factory));
+}
+
+void DesktopCapturerWrapper::CaptureFrame() {
+ base_capturer_->CaptureFrame();
+}
+
+void DesktopCapturerWrapper::SetExcludedWindow(WindowId window) {
+ base_capturer_->SetExcludedWindow(window);
+}
+
+bool DesktopCapturerWrapper::GetSourceList(SourceList* sources) {
+ return base_capturer_->GetSourceList(sources);
+}
+
+bool DesktopCapturerWrapper::SelectSource(SourceId id) {
+ return base_capturer_->SelectSource(id);
+}
+
+bool DesktopCapturerWrapper::FocusOnSelectedSource() {
+ return base_capturer_->FocusOnSelectedSource();
+}
+
+bool DesktopCapturerWrapper::IsOccluded(const DesktopVector& pos) {
+ return base_capturer_->IsOccluded(pos);
+}
+
+} // namespace webrtc
diff --git a/modules/desktop_capture/desktop_capturer_wrapper.h b/modules/desktop_capture/desktop_capturer_wrapper.h
new file mode 100644
index 0000000..a4b7b86
--- /dev/null
+++ b/modules/desktop_capture/desktop_capturer_wrapper.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2017 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 MODULES_DESKTOP_CAPTURE_DESKTOP_CAPTURER_WRAPPER_H_
+#define MODULES_DESKTOP_CAPTURE_DESKTOP_CAPTURER_WRAPPER_H_
+
+#include <memory>
+
+#include "modules/desktop_capture/desktop_capturer.h"
+
+namespace webrtc {
+
+// Wraps a DesktopCapturer and forwards all the function calls to it.
+class DesktopCapturerWrapper : public DesktopCapturer {
+ public:
+ explicit DesktopCapturerWrapper(
+ std::unique_ptr<DesktopCapturer> base_capturer);
+ ~DesktopCapturerWrapper() override;
+
+ // DesktopCapturer implementations.
+ void Start(Callback* callback) override;
+ void SetSharedMemoryFactory(
+ std::unique_ptr<SharedMemoryFactory> shared_memory_factory) override;
+ void CaptureFrame() override;
+ void SetExcludedWindow(WindowId window) override;
+ bool GetSourceList(SourceList* sources) override;
+ bool SelectSource(SourceId id) override;
+ bool FocusOnSelectedSource() override;
+ bool IsOccluded(const DesktopVector& pos) override;
+
+ protected:
+ // Guaranteed to be valid.
+ const std::unique_ptr<DesktopCapturer> base_capturer_;
+};
+
+} // namespace webrtc
+
+#endif // MODULES_DESKTOP_CAPTURE_DESKTOP_CAPTURER_WRAPPER_H_
