/*
* Copyright (C) 2003-2015 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_DIRECTORY_HXX
#define MPD_DIRECTORY_HXX
#include "check.h"
#include "Compiler.h"
#include "db/Visitor.hxx"
#include "db/PlaylistVector.hxx"
#include "Song.hxx"
#include <boost/intrusive/list.hpp>
#include <string>
/**
* Virtual directory that is really an archive file or a folder inside
* the archive (special value for Directory::device).
*/
static constexpr unsigned DEVICE_INARCHIVE = -1;
/**
* Virtual directory that is really a song file with one or more "sub"
* songs as specified by DecoderPlugin::container_scan() (special
* value for Directory::device).
*/
static constexpr unsigned DEVICE_CONTAINER = -2;
struct db_visitor;
class SongFilter;
class Error;
class Database;
struct Directory {
static constexpr auto link_mode = boost::intrusive::normal_link;
typedef boost::intrusive::link_mode<link_mode> LinkMode;
typedef boost::intrusive::list_member_hook<LinkMode> Hook;
/**
* Pointers to the siblings of this directory within the
* parent directory. It is unused (undefined) in the root
* directory.
*
* This attribute is protected with the global #db_mutex.
* Read access in the update thread does not need protection.
*/
Hook siblings;
typedef boost::intrusive::member_hook<Directory, Hook,
&Directory::siblings> SiblingsHook;
typedef boost::intrusive::list<Directory, SiblingsHook,
boost::intrusive::constant_time_size<false>> List;
/**
* A doubly linked list of child directories.
*
* This attribute is protected with the global #db_mutex.
* Read access in the update thread does not need protection.
*/
List children;
/**
* A doubly linked list of songs within this directory.
*
* This attribute is protected with the global #db_mutex.
* Read access in the update thread does not need protection.
*/
SongList songs;
PlaylistVector playlists;
Directory *parent;
time_t mtime;
unsigned inode, device;
std::string path;
/**
* If this is not nullptr, then this directory does not really
* exist, but is a mount point for another #Database.
*/
Database *mounted_database;
public:
Directory(std::string &&_path_utf8, Directory *_parent);
~Directory();
/**
* Create a new root #Directory object.
*/
gcc_malloc
static Directory *NewRoot() {
return new Directory(std::string(), nullptr);
}
bool IsMount() const {
return mounted_database != nullptr;
}
/**
* Remove this #Directory object from its parent and free it. This
* must not be called with the root Directory.
*
* Caller must lock the #db_mutex.
*/
void Delete();
/**
* Create a new #Directory object as a child of the given one.
*
* Caller must lock the #db_mutex.
*
* @param name_utf8 the UTF-8 encoded name of the new sub directory
*/
gcc_malloc
Directory *CreateChild(const char *name_utf8);
/**
* Caller must lock the #db_mutex.
*/
gcc_pure
const Directory *FindChild(const char *name) const;
gcc_pure
Directory *FindChild(const char *name) {
const Directory *cthis = this;
return const_cast<Directory *>(cthis->FindChild(name));
}
/**
* Look up a sub directory, and create the object if it does not
* exist.
*
* Caller must lock the #db_mutex.
*/
Directory *MakeChild(const char *name_utf8) {
Directory *child = FindChild(name_utf8);
if (child == nullptr)
child = CreateChild(name_utf8);
return child;
}
struct LookupResult {
/**
* The last directory that was found. If the given
* URI could not be resolved at all, then this is the
* root directory.
*/
Directory *directory;
/**
* The remaining URI part (without leading slash) or
* nullptr if the given URI was consumed completely.
*/
const char *uri;
};
/**
* Looks up a directory by its relative URI.
*
* @param uri the relative URI
* @return the Directory, or nullptr if none was found
*/
gcc_pure
LookupResult LookupDirectory(const char *uri);
gcc_pure
bool IsEmpty() const {
return children.empty() &&
songs.empty() &&
playlists.empty();
}
gcc_pure
const char *GetPath() const {
return path.c_str();
}
/**
* Returns the base name of the directory.
*/
gcc_pure
const char *GetName() const;
/**
* Is this the root directory of the music database?
*/
gcc_pure
bool IsRoot() const {
return parent == nullptr;
}
template<typename T>
void ForEachChildSafe(T &&t) {
const auto end = children.end();
for (auto i = children.begin(), next = i; i != end; i = next) {
next = std::next(i);
t(*i);
}
}
template<typename T>
void ForEachSongSafe(T &&t) {
const auto end = songs.end();
for (auto i = songs.begin(), next = i; i != end; i = next) {
next = std::next(i);
t(*i);
}
}
/**
* Look up a song in this directory by its name.
*
* Caller must lock the #db_mutex.
*/
gcc_pure
const Song *FindSong(const char *name_utf8) const;
gcc_pure
Song *FindSong(const char *name_utf8) {
const Directory *cthis = this;
return const_cast<Song *>(cthis->FindSong(name_utf8));
}
/**
* Add a song object to this directory. Its "parent" attribute must
* be set already.
*/
void AddSong(Song *song);
/**
* Remove a song object from this directory (which effectively
* invalidates the song object, because the "parent" attribute becomes
* stale), but does not free it.
*/
void RemoveSong(Song *song);
/**
* Caller must lock the #db_mutex.
*/
void PruneEmpty();
/**
* Sort all directory entries recursively.
*
* Caller must lock the #db_mutex.
*/
void Sort();
/**
* Caller must lock #db_mutex.
*/
bool Walk(bool recursive, const SongFilter *match,
VisitDirectory visit_directory, VisitSong visit_song,
VisitPlaylist visit_playlist,
Error &error) const;
gcc_pure
LightDirectory Export() const;
};
#endif
