Bug 1672072 - P1. Add async wrapper. r=mattwoodrow,bryce,mjf,padenot

This method will become the main entry point of a PDM and allow to create a decoder asynchronously for PDM not supporting that interface.

Differential Revision: https://phabricator.services.mozilla.com/D96357

dom/media/platforms/PlatformDecoderModule.cpp

@@ -0,0 +1,53 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "PlatformDecoderModule.h"
+
+#include "nsPrintfCString.h"
+
+namespace mozilla {
+
+RefPtr<PlatformDecoderModule::CreateDecoderPromise>
+PlatformDecoderModule::AsyncCreateDecoder(const CreateDecoderParams& aParams) {
+  RefPtr<MediaDataDecoder> decoder;
+  if (aParams.mError) {
+    *aParams.mError = NS_OK;
+  }
+  if (aParams.mConfig.IsAudio()) {
+    decoder = CreateAudioDecoder(aParams);
+  } else if (aParams.mConfig.IsVideo()) {
+    decoder = CreateAudioDecoder(aParams);
+  }
+  if (!decoder) {
+    if (aParams.mError && NS_FAILED(*aParams.mError)) {
+      return CreateDecoderPromise::CreateAndReject(*aParams.mError, __func__);
+    }
+    return CreateDecoderPromise::CreateAndReject(
+        MediaResult(NS_ERROR_DOM_MEDIA_FATAL_ERR,
+                    nsPrintfCString("Error creating decoder for %s",
+                                    aParams.mConfig.mMimeType.get())
+                        .get()),
+        __func__);
+  }
+  RefPtr<CreateDecoderPromise> p = decoder->Init()->Then(
+      GetCurrentSerialEventTarget(), __func__,
+      [decoder](MediaDataDecoder::InitPromise::ResolveOrRejectValue&& aValue) {
+        RefPtr<CreateDecoderPromise> p;
+        if (aValue.IsReject()) {
+          p = decoder->Shutdown()->Then(
+              GetCurrentSerialEventTarget(), __func__,
+              [reject = aValue.RejectValue()]() {
+                return CreateDecoderPromise::CreateAndReject(reject, __func__);
+              });
+        } else {
+          p = CreateDecoderPromise::CreateAndResolve(decoder, __func__);
+        }
+        return p;
+      });
+  return p;
+}
+
+}  // namespace mozilla

dom/media/platforms/PlatformDecoderModule.h

@@ -270,6 +270,10 @@ class PlatformDecoderModule {
            SupportsColorDepth(videoInfo->mColorDepth, aDiagnostics);
   }
 
+  typedef MozPromise<RefPtr<MediaDataDecoder>, MediaResult,
+                     /* IsExclusive = */ true>
+      CreateDecoderPromise;
+
  protected:
   PlatformDecoderModule() = default;
   virtual ~PlatformDecoderModule() = default;
@@ -318,6 +322,10 @@ class PlatformDecoderModule {
   // not to allow for fallback PDMs to be tried.
   virtual already_AddRefed<MediaDataDecoder> CreateAudioDecoder(
       const CreateDecoderParams& aParams) = 0;
+
+  // Asychronously create a decoder.
+  virtual RefPtr<CreateDecoderPromise> AsyncCreateDecoder(
+      const CreateDecoderParams& aParams);
 };
 
 DDLoggedTypeDeclName(MediaDataDecoder);

dom/media/platforms/moz.build

@@ -39,6 +39,7 @@ UNIFIED_SOURCES += [
     "AllocationPolicy.cpp",
     "PDMFactory.cpp",
     "PEMFactory.cpp",
+    "PlatformDecoderModule.cpp",
     "wrappers/AudioTrimmer.cpp",
     "wrappers/MediaChangeMonitor.cpp",
     "wrappers/MediaDataDecoderProxy.cpp",