1 files changed, 112 insertions, 0 deletions
diff --git a/dom/media/eme/CDMCaps.cpp b/dom/media/eme/CDMCaps.cpp
new file mode 100644
index 0000000000..2752ada476
--- /dev/null
+++ b/dom/media/eme/CDMCaps.cpp
@@ -0,0 +1,112 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "mozilla/CDMCaps.h"
+#include "mozilla/EMEUtils.h"
+#include "nsThreadUtils.h"
+#include "SamplesWaitingForKey.h"
+
+namespace mozilla {
+
+CDMCaps::CDMCaps() = default;
+
+CDMCaps::~CDMCaps() = default;
+
+// Keys with MediaKeyStatus::Usable, MediaKeyStatus::Output_downscaled,
+// or MediaKeyStatus::Output_restricted status can be used by the CDM
+// to decrypt or decrypt-and-decode samples.
+static bool IsUsableStatus(dom::MediaKeyStatus aStatus) {
+  return aStatus == dom::MediaKeyStatus::Usable ||
+         aStatus == dom::MediaKeyStatus::Output_restricted ||
+         aStatus == dom::MediaKeyStatus::Output_downscaled;
+}
+
+bool CDMCaps::IsKeyUsable(const CencKeyId& aKeyId) {
+  for (const KeyStatus& keyStatus : mKeyStatuses) {
+    if (keyStatus.mId == aKeyId) {
+      return IsUsableStatus(keyStatus.mStatus);
+    }
+  }
+  return false;
+}
+
+bool CDMCaps::SetKeyStatus(const CencKeyId& aKeyId, const nsString& aSessionId,
+                           const dom::Optional<dom::MediaKeyStatus>& aStatus) {
+  if (!aStatus.WasPassed()) {
+    // Called from ForgetKeyStatus.
+    // Return true if the element is found to notify key changes.
+    return mKeyStatuses.RemoveElement(
+        KeyStatus(aKeyId, aSessionId, dom::MediaKeyStatus::Internal_error));
+  }
+
+  KeyStatus key(aKeyId, aSessionId, aStatus.Value());
+  auto index = mKeyStatuses.IndexOf(key);
+  if (index != mKeyStatuses.NoIndex) {
+    if (mKeyStatuses[index].mStatus == aStatus.Value()) {
+      // No change.
+      return false;
+    }
+    auto oldStatus = mKeyStatuses[index].mStatus;
+    mKeyStatuses[index].mStatus = aStatus.Value();
+    // The old key status was one for which we can decrypt media. We don't
+    // need to do the "notify usable" step below, as it should be impossible
+    // for us to have anything waiting on this key to become usable, since it
+    // was already usable.
+    if (IsUsableStatus(oldStatus)) {
+      return true;
+    }
+  } else {
+    mKeyStatuses.AppendElement(key);
+  }
+
+  // Only call NotifyUsable() for a key when we are going from non-usable
+  // to usable state.
+  if (!IsUsableStatus(aStatus.Value())) {
+    return true;
+  }
+
+  auto& waiters = mWaitForKeys;
+  size_t i = 0;
+  while (i < waiters.Length()) {
+    auto& w = waiters[i];
+    if (w.mKeyId == aKeyId) {
+      w.mListener->NotifyUsable(aKeyId);
+      waiters.RemoveElementAt(i);
+    } else {
+      i++;
+    }
+  }
+  return true;
+}
+
+void CDMCaps::NotifyWhenKeyIdUsable(const CencKeyId& aKey,
+                                    SamplesWaitingForKey* aListener) {
+  MOZ_ASSERT(!IsKeyUsable(aKey));
+  MOZ_ASSERT(aListener);
+  mWaitForKeys.AppendElement(WaitForKeys(aKey, aListener));
+}
+
+void CDMCaps::GetKeyStatusesForSession(const nsAString& aSessionId,
+                                       nsTArray<KeyStatus>& aOutKeyStatuses) {
+  for (const KeyStatus& keyStatus : mKeyStatuses) {
+    if (keyStatus.mSessionId.Equals(aSessionId)) {
+      aOutKeyStatuses.AppendElement(keyStatus);
+    }
+  }
+}
+
+bool CDMCaps::RemoveKeysForSession(const nsString& aSessionId) {
+  bool changed = false;
+  nsTArray<KeyStatus> statuses;
+  GetKeyStatusesForSession(aSessionId, statuses);
+  for (const KeyStatus& status : statuses) {
+    changed |= SetKeyStatus(status.mId, aSessionId,
+                            dom::Optional<dom::MediaKeyStatus>());
+  }
+  return changed;
+}
+
+}  // namespace mozilla