mapper: convert to C++

src/Mapper.cxx

@@ -0,0 +1,297 @@
+/*
+ * Copyright (C) 2003-2013 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.
+ */
+
+/*
+ * Maps directory and song objects to file system paths.
+ */
+
+#include "config.h"
+#include "Mapper.hxx"
+#include "directory.h"
+#include "song.h"
+
+extern "C" {
+#include "path.h"
+}
+
+#include <glib.h>
+
+#include <assert.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+#include <dirent.h>
+
+/**
+ * The absolute path of the music directory encoded in UTF-8.
+ */
+static char *music_dir_utf8;
+static size_t music_dir_utf8_length;
+
+/**
+ * The absolute path of the music directory encoded in the filesystem
+ * character set.
+ */
+static char *music_dir_fs;
+static size_t music_dir_fs_length;
+
+/**
+ * The absolute path of the playlist directory encoded in the
+ * filesystem character set.
+ */
+static char *playlist_dir_fs;
+
+/**
+ * Duplicate a string, chop all trailing slashes.
+ */
+static char *
+strdup_chop_slash(const char *path_fs)
+{
+	size_t length = strlen(path_fs);
+
+	while (length > 0 && path_fs[length - 1] == G_DIR_SEPARATOR)
+		--length;
+
+	return g_strndup(path_fs, length);
+}
+
+static void
+check_directory(const char *path)
+{
+	struct stat st;
+	if (stat(path, &st) < 0) {
+		g_warning("Failed to stat directory \"%s\": %s",
+			  path, g_strerror(errno));
+		return;
+	}
+
+	if (!S_ISDIR(st.st_mode)) {
+		g_warning("Not a directory: %s", path);
+		return;
+	}
+
+#ifndef WIN32
+	char *x = g_build_filename(path, ".", NULL);
+	if (stat(x, &st) < 0 && errno == EACCES)
+		g_warning("No permission to traverse (\"execute\") directory: %s",
+			  path);
+	g_free(x);
+#endif
+
+	DIR *dir = opendir(path);
+	if (dir != NULL)
+		closedir(dir);
+	else if (errno == EACCES)
+		g_warning("No permission to read directory: %s", path);
+}
+
+static void
+mapper_set_music_dir(const char *path_utf8)
+{
+	music_dir_utf8 = strdup_chop_slash(path_utf8);
+	music_dir_utf8_length = strlen(music_dir_utf8);
+
+	music_dir_fs = utf8_to_fs_charset(music_dir_utf8);
+	check_directory(music_dir_fs);
+	music_dir_fs_length = strlen(music_dir_fs);
+}
+
+static void
+mapper_set_playlist_dir(const char *path_utf8)
+{
+	playlist_dir_fs = utf8_to_fs_charset(path_utf8);
+	check_directory(playlist_dir_fs);
+}
+
+void mapper_init(const char *_music_dir, const char *_playlist_dir)
+{
+	if (_music_dir != NULL)
+		mapper_set_music_dir(_music_dir);
+
+	if (_playlist_dir != NULL)
+		mapper_set_playlist_dir(_playlist_dir);
+}
+
+void mapper_finish(void)
+{
+	g_free(music_dir_utf8);
+	g_free(music_dir_fs);
+	g_free(playlist_dir_fs);
+}
+
+const char *
+mapper_get_music_directory_utf8(void)
+{
+	return music_dir_utf8;
+}
+
+const char *
+mapper_get_music_directory_fs(void)
+{
+	return music_dir_fs;
+}
+
+const char *
+map_to_relative_path(const char *path_utf8)
+{
+	return music_dir_utf8 != NULL &&
+		memcmp(path_utf8, music_dir_utf8,
+		       music_dir_utf8_length) == 0 &&
+		G_IS_DIR_SEPARATOR(path_utf8[music_dir_utf8_length])
+		? path_utf8 + music_dir_utf8_length + 1
+		: path_utf8;
+}
+
+char *
+map_uri_fs(const char *uri)
+{
+	char *uri_fs, *path_fs;
+
+	assert(uri != NULL);
+	assert(*uri != '/');
+
+	if (music_dir_fs == NULL)
+		return NULL;
+
+	uri_fs = utf8_to_fs_charset(uri);
+	if (uri_fs == NULL)
+		return NULL;
+
+	path_fs = g_build_filename(music_dir_fs, uri_fs, NULL);
+	g_free(uri_fs);
+
+	return path_fs;
+}
+
+char *
+map_directory_fs(const struct directory *directory)
+{
+	assert(music_dir_utf8 != NULL);
+	assert(music_dir_fs != NULL);
+
+	if (directory_is_root(directory))
+		return g_strdup(music_dir_fs);
+
+	return map_uri_fs(directory_get_path(directory));
+}
+
+char *
+map_directory_child_fs(const struct directory *directory, const char *name)
+{
+	assert(music_dir_utf8 != NULL);
+	assert(music_dir_fs != NULL);
+
+	char *name_fs, *parent_fs, *path;
+
+	/* check for invalid or unauthorized base names */
+	if (*name == 0 || strchr(name, '/') != NULL ||
+	    strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
+		return NULL;
+
+	parent_fs = map_directory_fs(directory);
+	if (parent_fs == NULL)
+		return NULL;
+
+	name_fs = utf8_to_fs_charset(name);
+	if (name_fs == NULL) {
+		g_free(parent_fs);
+		return NULL;
+	}
+
+	path = g_build_filename(parent_fs, name_fs, NULL);
+	g_free(parent_fs);
+	g_free(name_fs);
+
+	return path;
+}
+
+/**
+ * Map a song object that was created by song_dup_detached().  It does
+ * not have a real parent directory, only the dummy object
+ * #detached_root.
+ */
+static char *
+map_detached_song_fs(const char *uri_utf8)
+{
+	char *uri_fs = utf8_to_fs_charset(uri_utf8);
+	if (uri_fs == NULL)
+		return NULL;
+
+	char *path = g_build_filename(music_dir_fs, uri_fs, NULL);
+	g_free(uri_fs);
+	return path;
+}
+
+char *
+map_song_fs(const struct song *song)
+{
+	assert(song_is_file(song));
+
+	if (song_in_database(song))
+		return song_is_detached(song)
+			? map_detached_song_fs(song->uri)
+			: map_directory_child_fs(song->parent, song->uri);
+	else
+		return utf8_to_fs_charset(song->uri);
+}
+
+char *
+map_fs_to_utf8(const char *path_fs)
+{
+	if (music_dir_fs != NULL &&
+	    strncmp(path_fs, music_dir_fs, music_dir_fs_length) == 0 &&
+	    G_IS_DIR_SEPARATOR(path_fs[music_dir_fs_length]))
+		/* remove musicDir prefix */
+		path_fs += music_dir_fs_length + 1;
+	else if (G_IS_DIR_SEPARATOR(path_fs[0]))
+		/* not within musicDir */
+		return NULL;
+
+	while (path_fs[0] == G_DIR_SEPARATOR)
+		++path_fs;
+
+	return fs_charset_to_utf8(path_fs);
+}
+
+const char *
+map_spl_path(void)
+{
+	return playlist_dir_fs;
+}
+
+char *
+map_spl_utf8_to_fs(const char *name)
+{
+	char *filename_utf8, *filename_fs, *path;
+
+	if (playlist_dir_fs == NULL)
+		return NULL;
+
+	filename_utf8 = g_strconcat(name, PLAYLIST_FILE_SUFFIX, NULL);
+	filename_fs = utf8_to_fs_charset(filename_utf8);
+	g_free(filename_utf8);
+	if (filename_fs == NULL)
+		return NULL;
+
+	path = g_build_filename(playlist_dir_fs, filename_fs, NULL);
+	g_free(filename_fs);
+
+	return path;
+}