media/libstagefright/include/ID3.h

/*
 * 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 ID3_H_

#define ID3_H_

#include <utils/RefBase.h>

namespace android {

class DataSourceBase;
class String8;
class DataSourceHelper;

struct ID3 {
    enum Version {
        ID3_UNKNOWN,
        ID3_V1,
        ID3_V1_1,
        ID3_V2_2,
        ID3_V2_3,
        ID3_V2_4,
    };

    explicit ID3(DataSourceHelper *source, bool ignoreV1 = false, off64_t offset = 0);
    explicit ID3(DataSourceBase *source, bool ignoreV1 = false, off64_t offset = 0);
    ID3(const uint8_t *data, size_t size, bool ignoreV1 = false);
    ~ID3();

    bool isValid() const;

    Version version() const;

    const void *getAlbumArt(size_t *length, String8 *mime) const;

    struct Iterator {
        Iterator(const ID3 &parent, const char *id);
        ~Iterator();

        bool done() const;
        void getID(String8 *id) const;
        void getString(String8 *s, String8 *ss = NULL) const;
        const uint8_t *getData(size_t *length) const;
        void next();

    private:
        const ID3 &mParent;
        char *mID;
        size_t mOffset;

        const uint8_t *mFrameData;
        size_t mFrameSize;

        void findFrame();

        size_t getHeaderLength() const;
        void getstring(String8 *s, bool secondhalf) const;

        Iterator(const Iterator &);
        Iterator &operator=(const Iterator &);
    };

    size_t rawSize() const { return mRawSize; }

private:
    bool mIsValid;
    uint8_t *mData;
    size_t mSize;
    size_t mFirstFrameOffset;
    Version mVersion;

    // size of the ID3 tag including header before any unsynchronization.
    // only valid for IDV2+
    size_t mRawSize;

    bool parseV1(DataSourceBase *source);
    bool parseV2(DataSourceBase *source, off64_t offset);
    void removeUnsynchronization();
    bool removeUnsynchronizationV2_4(bool iTunesHack);

    static bool ParseSyncsafeInteger(const uint8_t encoded[4], size_t *x);

    ID3(const ID3 &);
    ID3 &operator=(const ID3 &);
};

}  // namespace android

#endif  // ID3_H_