Merge "Initial check-in of new caching/prefetching data source implementation." into kraken

1 files changed, 93 insertions, 0 deletions

diff --git a/media/libstagefright/include/NuCachedSource2.h b/media/libstagefright/include/NuCachedSource2.h
new file mode 100644
index 0000000..c30f029
--- /dev/null
+++ b/media/libstagefright/include/NuCachedSource2.h
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2010 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 NU_CACHED_SOURCE_2_H_
+
+#define NU_CACHED_SOURCE_2_H_
+
+#include <media/stagefright/foundation/ABase.h>
+#include <media/stagefright/foundation/AHandlerReflector.h>
+#include <media/stagefright/DataSource.h>
+
+namespace android {
+
+struct ALooper;
+struct PageCache;
+
+struct NuCachedSource2 : public DataSource {
+    NuCachedSource2(const sp<DataSource> &source);
+
+    virtual status_t initCheck() const;
+
+    virtual ssize_t readAt(off_t offset, void *data, size_t size);
+
+    virtual status_t getSize(off_t *size);
+    virtual uint32_t flags();
+
+    ////////////////////////////////////////////////////////////////////////////
+
+    size_t cachedSize();
+    size_t approxDataRemaining(bool *eos);
+
+protected:
+    virtual ~NuCachedSource2();
+
+private:
+    friend struct AHandlerReflector<NuCachedSource2>;
+
+    enum {
+        kPageSize           = 16384,
+        kHighWaterThreshold = 3 * 1024 * 1024,
+        kLowWaterThreshold  = 512 * 1024,
+    };
+
+    enum {
+        kWhatFetchMore  = 'fetc',
+        kWhatRead       = 'read',
+    };
+
+    sp<DataSource> mSource;
+    sp<AHandlerReflector<NuCachedSource2> > mReflector;
+    sp<ALooper> mLooper;
+
+    Mutex mSerializer;
+    Mutex mLock;
+    Condition mCondition;
+
+    PageCache *mCache;
+    off_t mCacheOffset;
+    status_t mFinalStatus;
+    off_t mLastAccessPos;
+    sp<AMessage> mAsyncResult;
+    bool mFetching;
+
+    void onMessageReceived(const sp<AMessage> &msg);
+    void onFetch();
+    void onRead(const sp<AMessage> &msg);
+
+    void fetchInternal();
+    ssize_t readInternal(off_t offset, void *data, size_t size);
+    status_t seekInternal_l(off_t offset);
+
+    size_t approxDataRemaining_l(bool *eos);
+    void restartPrefetcherIfNecessary_l();
+
+    DISALLOW_EVIL_CONSTRUCTORS(NuCachedSource2);
+};
+
+}  // namespace android
+
+#endif  // NU_CACHED_SOURCE_2_H_