1 files changed, 222 insertions, 0 deletions
diff --git a/dom/media/systemservices/MediaSystemResourceService.cpp b/dom/media/systemservices/MediaSystemResourceService.cpp
new file mode 100644
index 0000000000..88c4566e76
--- /dev/null
+++ b/dom/media/systemservices/MediaSystemResourceService.cpp
@@ -0,0 +1,222 @@
+/* -*- 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 "MediaSystemResourceManagerParent.h"
+#include "mozilla/layers/CompositorThread.h"
+#include "mozilla/Unused.h"
+
+#include "MediaSystemResourceService.h"
+
+using namespace mozilla::layers;
+
+namespace mozilla {
+
+/* static */
+StaticRefPtr<MediaSystemResourceService> MediaSystemResourceService::sSingleton;
+
+/* static */
+MediaSystemResourceService* MediaSystemResourceService::Get() {
+  if (sSingleton) {
+    return sSingleton;
+  }
+  Init();
+  return sSingleton;
+}
+
+/* static */
+void MediaSystemResourceService::Init() {
+  if (!sSingleton) {
+    sSingleton = new MediaSystemResourceService();
+  }
+}
+
+/* static */
+void MediaSystemResourceService::Shutdown() {
+  if (sSingleton) {
+    sSingleton->Destroy();
+    sSingleton = nullptr;
+  }
+}
+
+MediaSystemResourceService::MediaSystemResourceService() : mDestroyed(false) {
+  MOZ_ASSERT(CompositorThreadHolder::IsInCompositorThread());
+}
+
+MediaSystemResourceService::~MediaSystemResourceService() = default;
+
+void MediaSystemResourceService::Destroy() { mDestroyed = true; }
+
+void MediaSystemResourceService::Acquire(
+    media::MediaSystemResourceManagerParent* aParent, uint32_t aId,
+    MediaSystemResourceType aResourceType, bool aWillWait) {
+  MOZ_ASSERT(CompositorThreadHolder::IsInCompositorThread());
+  MOZ_ASSERT(aParent);
+
+  if (mDestroyed) {
+    return;
+  }
+
+  MediaSystemResource* resource =
+      mResources.Get(static_cast<uint32_t>(aResourceType));
+
+  if (!resource || resource->mResourceCount == 0) {
+    // Resource does not exit
+    // Send fail response
+    mozilla::Unused << aParent->SendResponse(aId, false /* fail */);
+    return;
+  }
+
+  // Try to acquire a resource
+  if (resource->mAcquiredRequests.size() < resource->mResourceCount) {
+    // Resource is available
+    resource->mAcquiredRequests.push_back(
+        MediaSystemResourceRequest(aParent, aId));
+    // Send success response
+    mozilla::Unused << aParent->SendResponse(aId, true /* success */);
+    return;
+  }
+
+  if (!aWillWait) {
+    // Resource is not available and do not wait.
+    // Send fail response
+    mozilla::Unused << aParent->SendResponse(aId, false /* fail */);
+    return;
+  }
+  // Wait until acquire.
+  resource->mWaitingRequests.push_back(
+      MediaSystemResourceRequest(aParent, aId));
+}
+
+void MediaSystemResourceService::ReleaseResource(
+    media::MediaSystemResourceManagerParent* aParent, uint32_t aId,
+    MediaSystemResourceType aResourceType) {
+  MOZ_ASSERT(CompositorThreadHolder::IsInCompositorThread());
+  MOZ_ASSERT(aParent);
+
+  if (mDestroyed) {
+    return;
+  }
+
+  MediaSystemResource* resource =
+      mResources.Get(static_cast<uint32_t>(aResourceType));
+
+  if (!resource || resource->mResourceCount == 0) {
+    // Resource does not exit
+    return;
+  }
+  RemoveRequest(aParent, aId, aResourceType);
+  UpdateRequests(aResourceType);
+}
+
+void MediaSystemResourceService::ReleaseResource(
+    media::MediaSystemResourceManagerParent* aParent) {
+  MOZ_ASSERT(aParent);
+
+  if (mDestroyed) {
+    return;
+  }
+
+  for (const uint32_t& key : mResources.Keys()) {
+    RemoveRequests(aParent, static_cast<MediaSystemResourceType>(key));
+    UpdateRequests(static_cast<MediaSystemResourceType>(key));
+  }
+}
+
+void MediaSystemResourceService::RemoveRequest(
+    media::MediaSystemResourceManagerParent* aParent, uint32_t aId,
+    MediaSystemResourceType aResourceType) {
+  MOZ_ASSERT(aParent);
+
+  MediaSystemResource* resource =
+      mResources.Get(static_cast<uint32_t>(aResourceType));
+  if (!resource) {
+    return;
+  }
+
+  std::deque<MediaSystemResourceRequest>::iterator it;
+  std::deque<MediaSystemResourceRequest>& acquiredRequests =
+      resource->mAcquiredRequests;
+  for (it = acquiredRequests.begin(); it != acquiredRequests.end(); it++) {
+    if (((*it).mParent == aParent) && ((*it).mId == aId)) {
+      acquiredRequests.erase(it);
+      return;
+    }
+  }
+
+  std::deque<MediaSystemResourceRequest>& waitingRequests =
+      resource->mWaitingRequests;
+  for (it = waitingRequests.begin(); it != waitingRequests.end(); it++) {
+    if (((*it).mParent == aParent) && ((*it).mId == aId)) {
+      waitingRequests.erase(it);
+      return;
+    }
+  }
+}
+
+void MediaSystemResourceService::RemoveRequests(
+    media::MediaSystemResourceManagerParent* aParent,
+    MediaSystemResourceType aResourceType) {
+  MOZ_ASSERT(aParent);
+
+  MediaSystemResource* resource =
+      mResources.Get(static_cast<uint32_t>(aResourceType));
+
+  if (!resource || resource->mResourceCount == 0) {
+    // Resource does not exit
+    return;
+  }
+
+  std::deque<MediaSystemResourceRequest>::iterator it;
+  std::deque<MediaSystemResourceRequest>& acquiredRequests =
+      resource->mAcquiredRequests;
+  for (it = acquiredRequests.begin(); it != acquiredRequests.end();) {
+    if ((*it).mParent == aParent) {
+      it = acquiredRequests.erase(it);
+    } else {
+      it++;
+    }
+  }
+
+  std::deque<MediaSystemResourceRequest>& waitingRequests =
+      resource->mWaitingRequests;
+  for (it = waitingRequests.begin(); it != waitingRequests.end();) {
+    if ((*it).mParent == aParent) {
+      it = waitingRequests.erase(it);
+    } else {
+      it++;
+    }
+  }
+}
+
+void MediaSystemResourceService::UpdateRequests(
+    MediaSystemResourceType aResourceType) {
+  MediaSystemResource* resource =
+      mResources.Get(static_cast<uint32_t>(aResourceType));
+
+  if (!resource || resource->mResourceCount == 0) {
+    // Resource does not exit
+    return;
+  }
+
+  std::deque<MediaSystemResourceRequest>& acquiredRequests =
+      resource->mAcquiredRequests;
+  std::deque<MediaSystemResourceRequest>& waitingRequests =
+      resource->mWaitingRequests;
+
+  while ((acquiredRequests.size() < resource->mResourceCount) &&
+         (!waitingRequests.empty())) {
+    MediaSystemResourceRequest& request = waitingRequests.front();
+    MOZ_ASSERT(request.mParent);
+    // Send response
+    mozilla::Unused << request.mParent->SendResponse(request.mId,
+                                                     true /* success */);
+    // Move request to mAcquiredRequests
+    acquiredRequests.push_back(waitingRequests.front());
+    waitingRequests.pop_front();
+  }
+}
+
+}  // namespace mozilla