/*
* Copyright (C) 2003-2009 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 "database.h"
#include "directory.h"
#include "directory_save.h"
#include "song.h"
#include "path.h"
#include "stats.h"
#include "config.h"
#include <glib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "database"
#define DIRECTORY_INFO_BEGIN "info_begin"
#define DIRECTORY_INFO_END "info_end"
#define DIRECTORY_MPD_VERSION "mpd_version: "
#define DIRECTORY_FS_CHARSET "fs_charset: "
static char *database_path;
static struct directory *music_root;
static time_t database_mtime;
/**
* The quark used for GError.domain.
*/
static inline GQuark
db_quark(void)
{
return g_quark_from_static_string("database");
}
void
db_init(const char *path)
{
database_path = g_strdup(path);
if (path != NULL)
music_root = directory_new("", NULL);
}
void
db_finish(void)
{
assert((database_path == NULL) == (music_root == NULL));
if (music_root != NULL)
directory_free(music_root);
g_free(database_path);
}
void
db_clear(void)
{
assert(music_root != NULL);
directory_free(music_root);
music_root = directory_new("", NULL);
}
struct directory *
db_get_root(void)
{
assert(music_root != NULL);
return music_root;
}
struct directory *
db_get_directory(const char *name)
{
if (music_root == NULL)
return NULL;
if (name == NULL)
return music_root;
return directory_lookup_directory(music_root, name);
}
struct song *
db_get_song(const char *file)
{
struct song *song;
struct directory *directory;
char *duplicated, *shortname, *dir;
assert(file != NULL);
g_debug("get song: %s", file);
if (music_root == NULL)
return NULL;
duplicated = g_strdup(file);
shortname = strrchr(duplicated, '/');
if (!shortname) {
shortname = duplicated;
dir = NULL;
} else {
*shortname = '\0';
++shortname;
dir = duplicated;
}
directory = db_get_directory(dir);
if (directory != NULL)
song = songvec_find(&directory->songs, shortname);
else
song = NULL;
assert(song == NULL || song->parent == directory);
g_free(duplicated);
return song;
}
int
db_walk(const char *name,
int (*forEachSong)(struct song *, void *),
int (*forEachDir)(struct directory *, void *), void *data)
{
struct directory *directory;
if (music_root == NULL)
return -1;
if ((directory = db_get_directory(name)) == NULL) {
struct song *song;
if ((song = db_get_song(name)) && forEachSong) {
return forEachSong(song, data);
}
return -1;
}
return directory_walk(directory, forEachSong, forEachDir, data);
}
bool
db_check(void)
{
struct stat st;
assert(database_path != NULL);
/* Check if the file exists */
if (access(database_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 */
char *dirPath = g_path_get_dirname(database_path);
/* Check that the parent part of the path is a directory */
if (stat(dirPath, &st) < 0) {
g_free(dirPath);
g_warning("Couldn't stat parent directory of db file "
"\"%s\": %s", database_path, strerror(errno));
return false;
}
if (!S_ISDIR(st.st_mode)) {
g_free(dirPath);
g_warning("Couldn't create db file \"%s\" because the "
"parent path is not a directory", database_path);
return false;
}
/* Check if we can write to the directory */
if (access(dirPath, R_OK | W_OK)) {
g_warning("Can't create db file in \"%s\": %s",
dirPath, strerror(errno));
g_free(dirPath);
return false;
}
g_free(dirPath);
return true;
}
/* Path exists, now check if it's a regular file */
if (stat(database_path, &st) < 0) {
g_warning("Couldn't stat db file \"%s\": %s",
database_path, strerror(errno));
return false;
}
if (!S_ISREG(st.st_mode)) {
g_warning("db file \"%s\" is not a regular file", database_path);
return false;
}
/* And check that we can write to it */
if (access(database_path, R_OK | W_OK)) {
g_warning("Can't open db file \"%s\" for reading/writing: %s",
database_path, strerror(errno));
return false;
}
return true;
}
bool
db_save(void)
{
FILE *fp;
struct stat st;
assert(database_path != NULL);
assert(music_root != NULL);
g_debug("removing empty directories from DB");
directory_prune_empty(music_root);
g_debug("sorting DB");
directory_sort(music_root);
g_debug("writing DB");
fp = fopen(database_path, "w");
if (!fp) {
g_warning("unable to write to db file \"%s\": %s",
database_path, strerror(errno));
return false;
}
/* block signals when writing the db so we don't get a corrupted db */
fprintf(fp, "%s\n", DIRECTORY_INFO_BEGIN);
fprintf(fp, "%s%s\n", DIRECTORY_MPD_VERSION, VERSION);
fprintf(fp, "%s%s\n", DIRECTORY_FS_CHARSET, path_get_fs_charset());
fprintf(fp, "%s\n", DIRECTORY_INFO_END);
if (directory_save(fp, music_root) < 0) {
g_warning("Failed to write to database file: %s",
strerror(errno));
while (fclose(fp) && errno == EINTR);
return false;
}
while (fclose(fp) && errno == EINTR);
if (stat(database_path, &st) == 0)
database_mtime = st.st_mtime;
return true;
}
bool
db_load(GError **error)
{
FILE *fp = NULL;
struct stat st;
char buffer[100];
bool found_charset = false, found_version = false;
bool success;
assert(database_path != NULL);
assert(music_root != NULL);
if (!music_root)
music_root = directory_new("", NULL);
while (!(fp = fopen(database_path, "r")) && errno == EINTR) ;
if (fp == NULL) {
g_set_error(error, db_quark(), errno,
"Failed to open database file \"%s\": %s",
database_path, strerror(errno));
return false;
}
/* get initial info */
if (!fgets(buffer, sizeof(buffer), fp)) {
fclose(fp);
g_set_error(error, db_quark(), 0, "Unexpected end of file");
return false;
}
g_strchomp(buffer);
if (0 != strcmp(DIRECTORY_INFO_BEGIN, buffer)) {
fclose(fp);
g_set_error(error, db_quark(), 0, "Database corrupted");
return false;
}
while (fgets(buffer, sizeof(buffer), fp) &&
!g_str_has_prefix(buffer, DIRECTORY_INFO_END)) {
g_strchomp(buffer);
if (g_str_has_prefix(buffer, DIRECTORY_MPD_VERSION)) {
if (found_version) {
fclose(fp);
g_set_error(error, db_quark(), 0,
"Duplicate version line");
return false;
}
found_version = true;
} else if (g_str_has_prefix(buffer, DIRECTORY_FS_CHARSET)) {
const char *new_charset, *old_charset;
if (found_charset) {
fclose(fp);
g_set_error(error, db_quark(), 0,
"Duplicate charset line");
return false;
}
found_charset = true;
new_charset = &(buffer[strlen(DIRECTORY_FS_CHARSET)]);
old_charset = path_get_fs_charset();
if (old_charset != NULL
&& strcmp(new_charset, old_charset)) {
fclose(fp);
g_message("Existing database has charset \"%s\" "
"instead of \"%s\"; "
"discarding database file",
new_charset, old_charset);
return false;
}
} else {
fclose(fp);
g_set_error(error, db_quark(), 0,
"Malformed line: %s", buffer);
return false;
}
}
g_debug("reading DB");
success = directory_load(fp, music_root, error);
while (fclose(fp) && errno == EINTR) ;
if (!success)
return false;
stats_update();
if (stat(database_path, &st) == 0)
database_mtime = st.st_mtime;
return true;
}
time_t
db_get_mtime(void)
{
return database_mtime;
}