command: "load" supports remote playlists (m3u, xspf, lastfm://)

This patch integrates the playlist plugin API to the MPD core.  We'll
be able to do much more in the future with that API, that's just the
beginning.

3 files changed, 147 insertions, 0 deletions

diff --git a/src/command.c b/src/command.c
index 1829f360a..9a34093b6 100644
--- a/src/command.c
+++ b/src/command.c
@@ -22,6 +22,7 @@
 #include "playlist.h"
 #include "playlist_print.h"
 #include "playlist_save.h"
+#include "playlist_queue.h"
 #include "queue_print.h"
 #include "ls.h"
 #include "uri.h"
@@ -707,6 +708,10 @@ handle_load(struct client *client, G_GNUC_UNUSED int argc, char *argv[])
 {
 	enum playlist_result result;
 
+	result = playlist_open_into_queue(argv[1], &g_playlist);
+	if (result != PLAYLIST_RESULT_NO_SUCH_LIST)
+		return result;
+
 	result = playlist_load_spl(&g_playlist, argv[1]);
 	return print_playlist_result(client, result);
 }
diff --git a/src/playlist_queue.c b/src/playlist_queue.c
new file mode 100644
index 000000000..f31eb9f42
--- /dev/null
+++ b/src/playlist_queue.c
@@ -0,0 +1,94 @@
+/*
+ * 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 "playlist_queue.h"
+#include "playlist_list.h"
+#include "playlist_plugin.h"
+#include "song.h"
+#include "uri.h"
+#include "ls.h"
+#include "input_stream.h"
+
+/**
+ * Determins if it's allowed to add this song to the playlist.  For
+ * safety reasons, we disallow local files.
+ */
+static inline bool
+accept_song(const struct song *song)
+{
+	return !song_is_file(song) && uri_has_scheme(song->uri) &&
+		uri_supported_scheme(song->uri);
+}
+
+enum playlist_result
+playlist_load_into_queue(struct playlist_provider *source,
+			 struct playlist *dest)
+{
+	enum playlist_result result;
+	struct song *song;
+
+	while ((song = playlist_plugin_read(source)) != NULL) {
+		if (!accept_song(song)) {
+			song_free(song);
+			continue;
+		}
+
+		result = playlist_append_song(dest, song, NULL);
+		if (result != PLAYLIST_RESULT_SUCCESS) {
+			song_free(song);
+			return result;
+		}
+	}
+
+	return PLAYLIST_RESULT_SUCCESS;
+}
+
+enum playlist_result
+playlist_open_into_queue(const char *uri, struct playlist *dest)
+{
+	struct playlist_provider *playlist;
+	bool stream = false;
+	struct input_stream is;
+	enum playlist_result result;
+
+	if (!uri_has_scheme(uri))
+		/* don't allow local playlist files for now */
+		return PLAYLIST_RESULT_NO_SUCH_LIST;
+
+	playlist = playlist_list_open_uri(uri);
+	if (playlist == NULL) {
+		stream = input_stream_open(&is, uri);
+		if (!stream)
+			return PLAYLIST_RESULT_NO_SUCH_LIST;
+
+		playlist = playlist_list_open_stream(&is, uri);
+		if (playlist == NULL) {
+			input_stream_close(&is);
+			return PLAYLIST_RESULT_NO_SUCH_LIST;
+		}
+	}
+
+	result = playlist_load_into_queue(playlist, dest);
+	playlist_plugin_close(playlist);
+
+	if (stream)
+		input_stream_close(&is);
+
+	return result;
+}
diff --git a/src/playlist_queue.h b/src/playlist_queue.h
new file mode 100644
index 000000000..b571cd63a
--- /dev/null
+++ b/src/playlist_queue.h
@@ -0,0 +1,48 @@
+/*
+ * 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.
+ */
+
+/*! \file
+ * \brief Glue between playlist plugin and the play queue
+ */
+
+#ifndef MPD_PLAYLIST_QUEUE_H
+#define MPD_PLAYLIST_QUEUE_H
+
+#include "playlist.h"
+
+struct playlist_provider;
+struct playlist;
+
+/**
+ * Loads the contents of a playlist and append it to the specified
+ * play queue.
+ */
+enum playlist_result
+playlist_load_into_queue(struct playlist_provider *source,
+			 struct playlist *dest);
+
+/**
+ * Opens a playlist with a playlist plugin and append to the specified
+ * play queue.
+ */
+enum playlist_result
+playlist_open_into_queue(const char *uri, struct playlist *dest);
+
+#endif
+