/*
* Copyright (C) 2003-2011 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.
*/
#include "config.h"
#include "SimpleDatabasePlugin.hxx"
#include "DatabaseSelection.hxx"
#include "DatabaseHelpers.hxx"
#include "Directory.hxx"
#include "SongFilter.hxx"
#include "DatabaseSave.hxx"
#include "DatabaseLock.hxx"
#include "DatabaseError.hxx"
#include "TextFile.hxx"
#include "ConfigData.hxx"
#include "fs/FileSystem.hxx"
#include "util/Error.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"
#include <sys/types.h>
#include <errno.h>
static constexpr Domain simple_db_domain("simple_db");
Database *
SimpleDatabase::Create(const config_param ¶m, Error &error)
{
SimpleDatabase *db = new SimpleDatabase();
if (!db->Configure(param, error)) {
delete db;
db = NULL;
}
return db;
}
bool
SimpleDatabase::Configure(const config_param ¶m, Error &error)
{
path = param.GetBlockPath("path", error);
if (path.IsNull()) {
if (!error.IsDefined())
error.Set(simple_db_domain,
"No \"path\" parameter specified");
return false;
}
path_utf8 = path.ToUTF8();
return true;
}
bool
SimpleDatabase::Check(Error &error) const
{
assert(!path.IsNull());
/* Check if the file exists */
if (!CheckAccess(path, F_OK)) {
/* If the file doesn't exist, we can't check if we can write
* it, so we are going to try to get the directory path, and
* see if we can write a file in that */
const auto dirPath = path.GetDirectoryName();
/* Check that the parent part of the path is a directory */
struct stat st;
if (!StatFile(dirPath, st)) {
error.FormatErrno("Couldn't stat parent directory of db file "
"\"%s\"",
path_utf8.c_str());
return false;
}
if (!S_ISDIR(st.st_mode)) {
error.Format(simple_db_domain,
"Couldn't create db file \"%s\" because the "
"parent path is not a directory",
path_utf8.c_str());
return false;
}
/* Check if we can write to the directory */
if (!CheckAccess(dirPath, X_OK | W_OK)) {
const int e = errno;
const std::string dirPath_utf8 = dirPath.ToUTF8();
error.FormatErrno(e, "Can't create db file in \"%s\"",
dirPath_utf8.c_str());
return false;
}
return true;
}
/* Path exists, now check if it's a regular file */
struct stat st;
if (!StatFile(path, st)) {
error.FormatErrno("Couldn't stat db file \"%s\"",
path_utf8.c_str());
return false;
}
if (!S_ISREG(st.st_mode)) {
error.Format(simple_db_domain,
"db file \"%s\" is not a regular file",
path_utf8.c_str());
return false;
}
/* And check that we can write to it */
if (!CheckAccess(path, R_OK | W_OK)) {
error.FormatErrno("Can't open db file \"%s\" for reading/writing",
path_utf8.c_str());
return false;
}
return true;
}
bool
SimpleDatabase::Load(Error &error)
{
assert(!path.IsNull());
assert(root != NULL);
TextFile file(path);
if (file.HasFailed()) {
error.FormatErrno("Failed to open database file \"%s\"",
path_utf8.c_str());
return false;
}
if (!db_load_internal(file, root, error))
return false;
struct stat st;
if (StatFile(path, st))
mtime = st.st_mtime;
return true;
}
bool
SimpleDatabase::Open(Error &error)
{
root = Directory::NewRoot();
mtime = 0;
#ifndef NDEBUG
borrowed_song_count = 0;
#endif
if (!Load(error)) {
root->Free();
LogError(error);
error.Clear();
if (!Check(error))
return false;
root = Directory::NewRoot();
}
return true;
}
void
SimpleDatabase::Close()
{
assert(root != NULL);
assert(borrowed_song_count == 0);
root->Free();
}
Song *
SimpleDatabase::GetSong(const char *uri, Error &error) const
{
assert(root != NULL);
db_lock();
Song *song = root->LookupSong(uri);
db_unlock();
if (song == NULL)
error.Format(db_domain, DB_NOT_FOUND,
"No such song: %s", uri);
#ifndef NDEBUG
else
++const_cast<unsigned &>(borrowed_song_count);
#endif
return song;
}
void
SimpleDatabase::ReturnSong(gcc_unused Song *song) const
{
assert(song != nullptr);
#ifndef NDEBUG
assert(borrowed_song_count > 0);
--const_cast<unsigned &>(borrowed_song_count);
#endif
}
gcc_pure
const Directory *
SimpleDatabase::LookupDirectory(const char *uri) const
{
assert(root != NULL);
assert(uri != NULL);
ScopeDatabaseLock protect;
return root->LookupDirectory(uri);
}
bool
SimpleDatabase::Visit(const DatabaseSelection &selection,
VisitDirectory visit_directory,
VisitSong visit_song,
VisitPlaylist visit_playlist,
Error &error) const
{
ScopeDatabaseLock protect;
const Directory *directory = root->LookupDirectory(selection.uri);
if (directory == NULL) {
if (visit_song) {
Song *song = root->LookupSong(selection.uri);
if (song != nullptr)
return !selection.Match(*song) ||
visit_song(*song, error);
}
error.Set(db_domain, DB_NOT_FOUND, "No such directory");
return false;
}
if (selection.recursive && visit_directory &&
!visit_directory(*directory, error))
return false;
return directory->Walk(selection.recursive, selection.filter,
visit_directory, visit_song, visit_playlist,
error);
}
bool
SimpleDatabase::VisitUniqueTags(const DatabaseSelection &selection,
enum tag_type tag_type,
VisitString visit_string,
Error &error) const
{
return ::VisitUniqueTags(*this, selection, tag_type, visit_string,
error);
}
bool
SimpleDatabase::GetStats(const DatabaseSelection &selection,
DatabaseStats &stats, Error &error) const
{
return ::GetStats(*this, selection, stats, error);
}
bool
SimpleDatabase::Save(Error &error)
{
db_lock();
LogDebug(simple_db_domain, "removing empty directories from DB");
root->PruneEmpty();
LogDebug(simple_db_domain, "sorting DB");
root->Sort();
db_unlock();
LogDebug(simple_db_domain, "writing DB");
FILE *fp = FOpen(path, FOpenMode::WriteText);
if (!fp) {
error.FormatErrno("unable to write to db file \"%s\"",
path_utf8.c_str());
return false;
}
db_save_internal(fp, root);
if (ferror(fp)) {
error.SetErrno("Failed to write to database file");
fclose(fp);
return false;
}
fclose(fp);
struct stat st;
if (StatFile(path, st))
mtime = st.st_mtime;
return true;
}
const DatabasePlugin simple_db_plugin = {
"simple",
SimpleDatabase::Create,
};