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Diffstat (limited to 'libs/taglib/taglib/fileref.h')
| -rw-r--r-- | libs/taglib/taglib/fileref.h | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/libs/taglib/taglib/fileref.h b/libs/taglib/taglib/fileref.h new file mode 100644 index 0000000000..cb4c2b41cc --- /dev/null +++ b/libs/taglib/taglib/fileref.h @@ -0,0 +1,262 @@ +/*************************************************************************** + copyright : (C) 2002 - 2008 by Scott Wheeler + email : wheeler@kde.org + ***************************************************************************/ + +/*************************************************************************** + * This library is free software; you can redistribute it and/or modify * + * it under the terms of the GNU Lesser General Public License version * + * 2.1 as published by the Free Software Foundation. * + * * + * This library is distributed in the hope that it will be useful, but * + * WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this library; if not, write to the Free Software * + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * + * USA * + * * + * Alternatively, this file is available under the Mozilla Public * + * License Version 1.1. You may obtain a copy of the License at * + * http://www.mozilla.org/MPL/ * + ***************************************************************************/ + +#ifndef TAGLIB_FILEREF_H +#define TAGLIB_FILEREF_H + +#include <tfile.h> +#include <tstringlist.h> + +#include "taglib_export.h" +#include "audioproperties.h" + +namespace TagLib { + + class Tag; + + //! This class provides a simple abstraction for creating and handling files + + /*! + * FileRef exists to provide a minimal, generic and value-based wrapper around + * a File. It is lightweight and implicitly shared, and as such suitable for + * pass-by-value use. This hides some of the uglier details of TagLib::File + * and the non-generic portions of the concrete file implementations. + * + * This class is useful in a "simple usage" situation where it is desirable + * to be able to get and set some of the tag information that is similar + * across file types. + * + * Also note that it is probably a good idea to plug this into your mime + * type system rather than using the constructor that accepts a file name using + * the FileTypeResolver. + * + * \see FileTypeResolver + * \see addFileTypeResolver() + */ + + class TAGLIB_EXPORT FileRef + { + public: + + //! A class for pluggable file type resolution. + + /*! + * This class is used to add extend TagLib's very basic file name based file + * type resolution. + * + * This can be accomplished with: + * + * \code + * + * class MyFileTypeResolver : FileTypeResolver + * { + * TagLib::File *createFile(TagLib::FileName *fileName, bool, AudioProperties::ReadStyle) + * { + * if(someCheckForAnMP3File(fileName)) + * return new TagLib::MPEG::File(fileName); + * return 0; + * } + * } + * + * FileRef::addFileTypeResolver(new MyFileTypeResolver); + * + * \endcode + * + * Naturally a less contrived example would be slightly more complex. This + * can be used to plug in mime-type detection systems or to add new file types + * to TagLib. + */ + + class TAGLIB_EXPORT FileTypeResolver + { + public: + // do not fix compiler warning about missing virtual destructor + // since this would not be binary compatible + // let Scott fix it whenever he thinks BIC changes can next be applied + /*! + * This method must be overridden to provide an additional file type + * resolver. If the resolver is able to determine the file type it should + * return a valid File object; if not it should return 0. + * + * \note The created file is then owned by the FileRef and should not be + * deleted. Deletion will happen automatically when the FileRef passes + * out of scope. + */ + virtual File *createFile(FileName fileName, + bool readAudioProperties = true, + AudioProperties::ReadStyle + audioPropertiesStyle = AudioProperties::Average) const = 0; + }; + + /*! + * Creates a null FileRef. + */ + FileRef(); + + /*! + * Create a FileRef from \a fileName. If \a readAudioProperties is true then + * the audio properties will be read using \a audioPropertiesStyle. If + * \a readAudioProperties is false then \a audioPropertiesStyle will be + * ignored. + * + * Also see the note in the class documentation about why you may not want to + * use this method in your application. + */ + explicit FileRef(FileName fileName, + bool readAudioProperties = true, + AudioProperties::ReadStyle + audioPropertiesStyle = AudioProperties::Average); + + /*! + * Contruct a FileRef using \a file. The FileRef now takes ownership of the + * pointer and will delete the File when it passes out of scope. + */ + explicit FileRef(File *file); + + /*! + * Make a copy of \a ref. + */ + FileRef(const FileRef &ref); + + /*! + * Destroys this FileRef instance. + */ + virtual ~FileRef(); + + /*! + * Returns a pointer to represented file's tag. + * + * \warning This pointer will become invalid when this FileRef and all + * copies pass out of scope. + * + * \see File::tag() + */ + Tag *tag() const; + + /*! + * Returns the audio properties for this FileRef. If no audio properties + * were read then this will returns a null pointer. + */ + AudioProperties *audioProperties() const; + + /*! + * Returns a pointer to the file represented by this handler class. + * + * As a general rule this call should be avoided since if you need to work + * with file objects directly, you are probably better served instantiating + * the File subclasses (i.e. MPEG::File) manually and working with their APIs. + * + * This <i>handle</i> exists to provide a minimal, generic and value-based + * wrapper around a File. Accessing the file directly generally indicates + * a moving away from this simplicity (and into things beyond the scope of + * FileRef). + * + * \warning This pointer will become invalid when this FileRef and all + * copies pass out of scope. + */ + File *file() const; + + /*! + * Saves the file. Returns true on success. + */ + bool save(); + + /*! + * Adds a FileTypeResolver to the list of those used by TagLib. Each + * additional FileTypeResolver is added to the front of a list of resolvers + * that are tried. If the FileTypeResolver returns zero the next resolver + * is tried. + * + * Returns a pointer to the added resolver (the same one that's passed in -- + * this is mostly so that static inialializers have something to use for + * assignment). + * + * \see FileTypeResolver + */ + static const FileTypeResolver *addFileTypeResolver(const FileTypeResolver *resolver); + + /*! + * As is mentioned elsewhere in this class's documentation, the default file + * type resolution code provided by TagLib only works by comparing file + * extensions. + * + * This method returns the list of file extensions that are used by default. + * + * The extensions are all returned in lowercase, though the comparison used + * by TagLib for resolution is case-insensitive. + * + * \note This does not account for any additional file type resolvers that + * are plugged in. Also note that this is not intended to replace a propper + * mime-type resolution system, but is just here for reference. + * + * \see FileTypeResolver + */ + static StringList defaultFileExtensions(); + + /*! + * Returns true if the file (and as such other pointers) are null. + */ + bool isNull() const; + + /*! + * Assign the file pointed to by \a ref to this FileRef. + */ + FileRef &operator=(const FileRef &ref); + + /*! + * Returns true if this FileRef and \a ref point to the same File object. + */ + bool operator==(const FileRef &ref) const; + + /*! + * Returns true if this FileRef and \a ref do not point to the same File + * object. + */ + bool operator!=(const FileRef &ref) const; + + /*! + * A simple implementation of file type guessing. If \a readAudioProperties + * is true then the audio properties will be read using + * \a audioPropertiesStyle. If \a readAudioProperties is false then + * \a audioPropertiesStyle will be ignored. + * + * \note You generally shouldn't use this method, but instead the constructor + * directly. + * + * \deprecated + */ + static File *create(FileName fileName, + bool readAudioProperties = true, + AudioProperties::ReadStyle audioPropertiesStyle = AudioProperties::Average); + + + private: + class FileRefPrivate; + FileRefPrivate *d; + }; + +} // namespace TagLib + +#endif |