diff options
Diffstat (limited to 'src/db/SimpleDatabasePlugin.cxx')
| -rw-r--r-- | src/db/SimpleDatabasePlugin.cxx | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/src/db/SimpleDatabasePlugin.cxx b/src/db/SimpleDatabasePlugin.cxx new file mode 100644 index 000000000..84e4e7cee --- /dev/null +++ b/src/db/SimpleDatabasePlugin.cxx @@ -0,0 +1,347 @@ +/* + * 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 "db_error.h" +#include "TextFile.hxx" + +extern "C" { +#include "conf.h" +} + +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <errno.h> + +G_GNUC_CONST +static inline GQuark +simple_db_quark(void) +{ + return g_quark_from_static_string("simple_db"); +} + +Database * +SimpleDatabase::Create(const struct config_param *param, GError **error_r) +{ + SimpleDatabase *db = new SimpleDatabase(); + if (!db->Configure(param, error_r)) { + delete db; + db = NULL; + } + + return db; +} + +bool +SimpleDatabase::Configure(const struct config_param *param, GError **error_r) +{ + GError *error = NULL; + + char *_path = config_dup_block_path(param, "path", &error); + if (_path == NULL) { + if (error != NULL) + g_propagate_error(error_r, error); + else + g_set_error(error_r, simple_db_quark(), 0, + "No \"path\" parameter specified"); + return false; + } + + path = _path; + free(_path); + + return true; +} + +bool +SimpleDatabase::Check(GError **error_r) const +{ + assert(!path.empty()); + + /* Check if the file exists */ + if (access(path.c_str(), 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 */ + char *dirPath = g_path_get_dirname(path.c_str()); + + /* Check that the parent part of the path is a directory */ + struct stat st; + if (stat(dirPath, &st) < 0) { + g_free(dirPath); + g_set_error(error_r, simple_db_quark(), errno, + "Couldn't stat parent directory of db file " + "\"%s\": %s", + path.c_str(), g_strerror(errno)); + return false; + } + + if (!S_ISDIR(st.st_mode)) { + g_free(dirPath); + g_set_error(error_r, simple_db_quark(), 0, + "Couldn't create db file \"%s\" because the " + "parent path is not a directory", + path.c_str()); + return false; + } + + /* Check if we can write to the directory */ + if (access(dirPath, X_OK | W_OK)) { + g_set_error(error_r, simple_db_quark(), errno, + "Can't create db file in \"%s\": %s", + dirPath, g_strerror(errno)); + g_free(dirPath); + return false; + } + + g_free(dirPath); + + return true; + } + + /* Path exists, now check if it's a regular file */ + struct stat st; + if (stat(path.c_str(), &st) < 0) { + g_set_error(error_r, simple_db_quark(), errno, + "Couldn't stat db file \"%s\": %s", + path.c_str(), g_strerror(errno)); + return false; + } + + if (!S_ISREG(st.st_mode)) { + g_set_error(error_r, simple_db_quark(), 0, + "db file \"%s\" is not a regular file", + path.c_str()); + return false; + } + + /* And check that we can write to it */ + if (access(path.c_str(), R_OK | W_OK)) { + g_set_error(error_r, simple_db_quark(), errno, + "Can't open db file \"%s\" for reading/writing: %s", + path.c_str(), g_strerror(errno)); + return false; + } + + return true; +} + +bool +SimpleDatabase::Load(GError **error_r) +{ + assert(!path.empty()); + assert(root != NULL); + + TextFile file(path.c_str()); + if (file.HasFailed()) { + g_set_error(error_r, simple_db_quark(), errno, + "Failed to open database file \"%s\": %s", + path.c_str(), g_strerror(errno)); + return false; + } + + if (!db_load_internal(file, root, error_r)) + return false; + + struct stat st; + if (stat(path.c_str(), &st) == 0) + mtime = st.st_mtime; + + return true; +} + +bool +SimpleDatabase::Open(GError **error_r) +{ + root = Directory::NewRoot(); + mtime = 0; + +#ifndef NDEBUG + borrowed_song_count = 0; +#endif + + GError *error = NULL; + if (!Load(&error)) { + root->Free(); + + g_warning("Failed to load database: %s", error->message); + g_error_free(error); + + if (!Check(error_r)) + return false; + + root = Directory::NewRoot(); + } + + return true; +} + +void +SimpleDatabase::Close() +{ + assert(root != NULL); + assert(borrowed_song_count == 0); + + root->Free(); +} + +struct song * +SimpleDatabase::GetSong(const char *uri, GError **error_r) const +{ + assert(root != NULL); + + db_lock(); + song *song = root->LookupSong(uri); + db_unlock(); + if (song == NULL) + g_set_error(error_r, db_quark(), 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 struct song *song) const +{ + assert(song != nullptr); + +#ifndef NDEBUG + assert(borrowed_song_count > 0); + --const_cast<unsigned &>(borrowed_song_count); +#endif +} + +G_GNUC_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, + GError **error_r) 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_r); + } + + g_set_error(error_r, db_quark(), DB_NOT_FOUND, + "No such directory"); + return false; + } + + if (selection.recursive && visit_directory && + !visit_directory(*directory, error_r)) + return false; + + return directory->Walk(selection.recursive, selection.filter, + visit_directory, visit_song, visit_playlist, + error_r); +} + +bool +SimpleDatabase::VisitUniqueTags(const DatabaseSelection &selection, + enum tag_type tag_type, + VisitString visit_string, + GError **error_r) const +{ + return ::VisitUniqueTags(*this, selection, tag_type, visit_string, + error_r); +} + +bool +SimpleDatabase::GetStats(const DatabaseSelection &selection, + DatabaseStats &stats, GError **error_r) const +{ + return ::GetStats(*this, selection, stats, error_r); +} + +bool +SimpleDatabase::Save(GError **error_r) +{ + db_lock(); + + g_debug("removing empty directories from DB"); + root->PruneEmpty(); + + g_debug("sorting DB"); + root->Sort(); + + db_unlock(); + + g_debug("writing DB"); + + FILE *fp = fopen(path.c_str(), "w"); + if (!fp) { + g_set_error(error_r, simple_db_quark(), errno, + "unable to write to db file \"%s\": %s", + path.c_str(), g_strerror(errno)); + return false; + } + + db_save_internal(fp, root); + + if (ferror(fp)) { + g_set_error(error_r, simple_db_quark(), errno, + "Failed to write to database file: %s", + g_strerror(errno)); + fclose(fp); + return false; + } + + fclose(fp); + + struct stat st; + if (stat(path.c_str(), &st) == 0) + mtime = st.st_mtime; + + return true; +} + +const DatabasePlugin simple_db_plugin = { + "simple", + SimpleDatabase::Create, +}; |