Add DRM session manager.

Bug: 19265536
Change-Id: Ia9f2c94c64ed6c1fe99d54de81d71c8973994865
diff --git a/media/libmediaplayerservice/DrmSessionManager.h b/media/libmediaplayerservice/DrmSessionManager.h
new file mode 100644
index 0000000..1d0ed43
--- /dev/null
+++ b/media/libmediaplayerservice/DrmSessionManager.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef DRM_SESSION_MANAGER_H_
+
+#define DRM_SESSION_MANAGER_H_
+
+#include <media/stagefright/foundation/ABase.h>
+#include <utils/RefBase.h>
+#include <utils/KeyedVector.h>
+#include <utils/threads.h>
+#include <utils/Vector.h>
+
+namespace android {
+
+class DrmSessionManagerTest;
+struct DrmSessionClientInterface;
+struct ProcessInfoInterface;
+
+bool isEqualSessionId(const Vector<uint8_t> &sessionId1, const Vector<uint8_t> &sessionId2);
+
+struct SessionInfo {
+    sp<DrmSessionClientInterface> drm;
+    Vector<uint8_t> sessionId;
+    int64_t timeStamp;
+};
+
+typedef Vector<SessionInfo > SessionInfos;
+typedef KeyedVector<int, SessionInfos > PidSessionInfosMap;
+
+struct DrmSessionManager : public RefBase {
+    DrmSessionManager();
+    DrmSessionManager(sp<ProcessInfoInterface> processInfo);
+
+    void addSession(int pid, sp<DrmSessionClientInterface> drm, const Vector<uint8_t>& sessionId);
+    void useSession(const Vector<uint8_t>& sessionId);
+    void removeSession(const Vector<uint8_t>& sessionId);
+    void removeDrm(sp<DrmSessionClientInterface> drm);
+    bool reclaimSession(int callingPid);
+
+protected:
+    virtual ~DrmSessionManager();
+
+private:
+    friend class DrmSessionManagerTest;
+
+    int64_t getTime_l();
+    bool getLowestPriority_l(int* lowestPriorityPid, int* lowestPriority);
+    bool getLeastUsedSession_l(
+            int pid, sp<DrmSessionClientInterface>* drm, Vector<uint8_t>* sessionId);
+
+    sp<ProcessInfoInterface> mProcessInfo;
+    mutable Mutex mLock;
+    PidSessionInfosMap mSessionMap;
+    int64_t mTime;
+
+    DISALLOW_EVIL_CONSTRUCTORS(DrmSessionManager);
+};
+
+}  // namespace android
+
+#endif  // DRM_SESSION_MANAGER_H_