Create a unified base class to access the database.

Moved the default database class to QListDB and disallow leaking CMAObjects outside this class.
Rewrote QListDB and CMAEvent to use the new internal API.
Moved the file format constants to the base database class.
Moved the metadata loading methods to the base database class.

src/database.h

@@ -0,0 +1,63 @@
+#ifndef DATABASE_H
+#define DATABASE_H
+
+#include <QObject>
+#include <vitamtp.h>
+
+typedef struct {
+    const char *file_ext;
+    int file_format;
+    int file_codec;
+} file_type;
+
+#define FILE_FORMAT_MP4 1
+#define FILE_FORMAT_WAV 2
+#define FILE_FORMAT_MP3 3
+#define FILE_FORMAT_JPG 4
+#define FILE_FORMAT_PNG 5
+#define FILE_FORMAT_GIF 6
+#define FILE_FORMAT_BMP 7
+#define FILE_FORMAT_TIF 8
+
+#define CODEC_TYPE_MPEG4 2
+#define CODEC_TYPE_AVC 3
+#define CODEC_TYPE_MP3 12
+#define CODEC_TYPE_AAC 13
+#define CODEC_TYPE_PCM 15
+#define CODEC_TYPE_JPG 17
+#define CODEC_TYPE_PNG 18
+#define CODEC_TYPE_TIF 19
+#define CODEC_TYPE_BMP 20
+#define CODEC_TYPE_GIF 21
+
+extern const file_type audio_list[3];
+extern const file_type photo_list[7];
+extern const file_type video_list[1];
+
+class Database : public QObject
+{
+    Q_OBJECT
+public:
+    explicit Database(QObject *parent = 0);
+
+    virtual int childObjectCount(int parent_ohfi) = 0;
+    virtual bool deleteEntry(int ohfi, int root_ohfi = 0) = 0;
+    virtual QString getAbsolutePath(int ohfi) = 0;
+    virtual QString getRelativePath(int ohfi) = 0;
+    virtual bool getObjectMetadata(int ohfi, metadata_t &metadata) = 0;
+    virtual int getObjectMetadatas(int parent_ohfi, metadata_t *&metadata, int index = 0, int max_number = 0) = 0;
+    virtual qint64 getObjectSize(int ohfi) = 0;
+    virtual int getPathId(const char *name, int ohfi) = 0;
+    virtual int insertObjectEntry(const QString &path, int parent_ohfi) = 0;
+    virtual bool renameObject(int ohfi, const QString &name) = 0;
+    virtual void setObjectSize(int ohfi, qint64 size) = 0;
+    virtual int getRootId(int ohfi) = 0;
+
+    static int checkFileType(const QString path, int ohfi_root);
+    static void loadMusicMetadata(const QString &path, metadata_t &metadata);
+    static void loadPhotoMetadata(const QString &path, metadata_t &metadata);
+    static void loadVideoMetadata(const QString &path, metadata_t &metadata);
+
+};
+
+#endif // DATABASE_H