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diff --git a/gfx/thebes/PrintTargetRecording.cpp b/gfx/thebes/PrintTargetRecording.cpp
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+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "PrintTargetRecording.h"
+
+#include "cairo.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/Logging.h"
+
+namespace mozilla {
+namespace gfx {
+
+PrintTargetRecording::PrintTargetRecording(cairo_surface_t* aCairoSurface,
+ const IntSize& aSize)
+ : PrintTarget(aCairoSurface, aSize) {}
+
+/* static */
+already_AddRefed<PrintTargetRecording> PrintTargetRecording::CreateOrNull(
+ const IntSize& aSize) {
+ if (!Factory::CheckSurfaceSize(aSize)) {
+ return nullptr;
+ }
+
+ // Perhaps surprisingly, this surface is never actually drawn to. This class
+ // creates a DrawTargetRecording using CreateRecordingDrawTarget, and
+ // that needs another DrawTarget to be passed to it. You might expect the
+ // type of the DrawTarget that is passed to matter because it would seem
+ // logical to encoded its type in the recording, and on replaying the
+ // recording a DrawTarget of the same type would be created. However, the
+ // passed DrawTarget's type doesn't seem to be encoded any more accurately
+ // than just "BackendType::CAIRO". Even if it were, the code that replays the
+ // recording is PrintTranslator::TranslateRecording which (indirectly) calls
+ // MakePrintTarget on the type of nsIDeviceContextSpecProxy that is created
+ // for the platform that we're running on, and the type of DrawTarget that
+ // that returns is hardcoded.
+ //
+ // The only reason that we use cairo_recording_surface_create here is:
+ //
+ // * It's pretty much the only cairo_*_surface_create methods that's both
+ // available on all platforms and doesn't require allocating a
+ // potentially large surface.
+ //
+ // * Since we need a DrawTarget to pass to CreateRecordingDrawTarget we
+ // might as well leverage our base class's machinery to create a
+ // DrawTarget (it's as good a way as any other that will work), and to do
+ // that we need a cairo_surface_t.
+ //
+ // So the fact that this is a "recording" PrintTarget and the function that
+ // we call here is cairo_recording_surface_create is simply a coincidence. We
+ // could use any cairo_*_surface_create method and this class would still
+ // work.
+ //
+ cairo_surface_t* surface =
+ cairo_recording_surface_create(CAIRO_CONTENT_COLOR_ALPHA, nullptr);
+
+ if (cairo_surface_status(surface)) {
+ return nullptr;
+ }
+
+ // The new object takes ownership of our surface reference.
+ RefPtr<PrintTargetRecording> target =
+ new PrintTargetRecording(surface, aSize);
+
+ return target.forget();
+}
+
+already_AddRefed<DrawTarget> PrintTargetRecording::MakeDrawTarget(
+ const IntSize& aSize, DrawEventRecorder* aRecorder) {
+ MOZ_ASSERT(aRecorder, "A DrawEventRecorder is required");
+
+ if (!aRecorder) {
+ return nullptr;
+ }
+
+ RefPtr<DrawTarget> dt = PrintTarget::MakeDrawTarget(aSize, nullptr);
+ if (dt) {
+ dt = CreateRecordingDrawTarget(aRecorder, dt);
+ if (!dt || !dt->IsValid()) {
+ return nullptr;
+ }
+ }
+
+ return dt.forget();
+}
+
+already_AddRefed<DrawTarget> PrintTargetRecording::CreateRecordingDrawTarget(
+ DrawEventRecorder* aRecorder, DrawTarget* aDrawTarget) {
+ MOZ_ASSERT(aRecorder);
+ MOZ_ASSERT(aDrawTarget);
+
+ RefPtr<DrawTarget> dt;
+
+ if (aRecorder) {
+ // It doesn't really matter what we pass as the DrawTarget here.
+ dt = gfx::Factory::CreateRecordingDrawTarget(aRecorder, aDrawTarget,
+ aDrawTarget->GetRect());
+ }
+
+ if (!dt || !dt->IsValid()) {
+ gfxCriticalNote
+ << "Failed to create a recording DrawTarget for PrintTarget";
+ return nullptr;
+ }
+
+ return dt.forget();
+}
+
+} // namespace gfx
+} // namespace mozilla