A soundcloud playlist plugin.

Requires YAJL to build, and this doesn't include the necessary
automake changes. Can be built using
./configure CFLAGS="-I/usr/include/yajl" LIBS="-lyajl" --enable-soundcloud

Add the following to your config:

playlist_plugin {
        name "soundcloud"
        enabled "true"
        apikey "c4c979fd6f241b5b30431d722af212e8"
}

Then you can stream from soundcloud using calls like:

mpc load soundcloud://track/<track-id>
mpc load soundcloud://playlist/<playlist-id>
mpc load soundcloud://url/http://soundcloud.com/some/track/or/playlist

For the last case, you can leave off the http:// or
http://soundcloud.com/ .

2 files changed, 447 insertions, 0 deletions

diff --git a/src/playlist/soundcloud_playlist_plugin.c b/src/playlist/soundcloud_playlist_plugin.c
new file mode 100644
index 00000000..b987de96
--- /dev/null
+++ b/src/playlist/soundcloud_playlist_plugin.c
@@ -0,0 +1,422 @@
+/*
+ * 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 "playlist/soundcloud_playlist_plugin.h"
+#include "conf.h"
+#include "input_stream.h"
+#include "playlist_plugin.h"
+#include "song.h"
+#include "tag.h"
+
+#include <glib.h>
+#include <yajl/yajl_parse.h>
+
+#include <string.h>
+
+struct soundcloud_playlist {
+	struct playlist_provider base;
+
+	GSList *songs;
+};
+
+static struct {
+	char *apikey;
+} soundcloud_config;
+
+static bool
+soundcloud_init(const struct config_param *param)
+{
+	const char *apikey = config_get_block_string(param, "apikey", NULL);
+
+	if (apikey == NULL) {
+		g_debug("disabling the soundcloud playlist plugin "
+			"because API key is not set");
+		return false;
+	}
+
+	soundcloud_config.apikey = g_strdup(apikey);
+
+	return true;
+}
+
+static void
+soundcloud_finish(void)
+{
+	g_free(soundcloud_config.apikey);
+}
+
+/**
+ * Construct a full soundcloud resolver URL from the given fragment.
+ * @param uri uri of a soundcloud page (or just the path)
+ * @return Constructed URL. Must be freed with g_free.
+ */
+static char *
+soundcloud_resolve(const char* uri) {
+	char *u, *ru;
+
+	if (g_str_has_prefix(uri, "http://")) {
+		u = g_strdup(uri);
+	} else if (g_str_has_prefix(uri, "soundcloud.com")) {
+		u = g_strconcat("http://", uri, NULL);
+	} else {
+		/* assume it's just a path on soundcloud.com */
+		u = g_strconcat("http://soundcloud.com/", uri, NULL);
+	}
+
+	ru = g_strconcat("http://api.soundcloud.com/resolve.json?url=",
+			u, "&client_id=", soundcloud_config.apikey, NULL);
+	g_free(u);
+
+	return ru;
+}
+
+/* YAJL parser for track data from both /tracks/ and /playlists/ JSON */
+
+enum key {
+	Duration,
+	Title,
+	Stream_URL,
+	Other,
+};
+
+const char* key_str[] = {
+	"duration",
+	"title",
+	"stream_url",
+	NULL,
+};
+
+struct parse_data {
+	int key;
+	char* stream_url;
+	long duration;
+	char* title;
+	int got_url; /* nesting level of last stream_url */
+	GSList* songs;
+};
+
+static int handle_integer(void *ctx, long intval)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+
+	switch (data->key) {
+	case Duration:
+		data->duration = intval;
+		break;
+	default:
+		break;
+	}
+
+	return 1;
+}
+
+static int handle_string(void *ctx, const unsigned char* stringval, unsigned int stringlen)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+	const char *s = (const char *) stringval;
+
+	switch (data->key) {
+	case Title:
+		if (data->title != NULL)
+			g_free(data->title);
+		data->title = g_strndup(s, stringlen);
+		break;
+	case Stream_URL:
+		if (data->stream_url != NULL)
+			g_free(data->stream_url);
+		data->stream_url = g_strndup(s, stringlen);
+		data->got_url = 1;
+		break;
+	default:
+		break;
+	}
+
+	return 1;
+}
+
+static int handle_mapkey(void *ctx, const unsigned char* stringval, unsigned int stringlen)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+
+	int i;
+	data->key = Other;
+
+	for (i = 0; i < Other; ++i) {
+		if (strncmp((const char *)stringval, key_str[i], stringlen) == 0) {
+			data->key = i;
+			break;
+		}
+	}
+
+	return 1;
+}
+
+static int handle_start_map(void *ctx)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+
+	if (data->got_url > 0)
+		data->got_url++;
+
+	return 1;
+}
+
+static int handle_end_map(void *ctx)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+
+	if (data->got_url > 1) {
+		data->got_url--;
+		return 1;
+	}
+
+	if (data->got_url == 0)
+		return 1;
+
+	/* got_url == 1, track finished, make it into a song */
+	data->got_url = 0;
+
+	struct song *s;
+	struct tag *t;
+	char *u;
+
+	u = g_strconcat(data->stream_url, "?client_id=", soundcloud_config.apikey, NULL);
+	s = song_remote_new(u);
+	g_free(u);
+	t = tag_new();
+	t->time = data->duration / 1000;
+	if (data->title != NULL)
+		tag_add_item(t, TAG_NAME, data->title);
+	s->tag = t;
+
+	data->songs = g_slist_prepend(data->songs, s);
+
+	return 1;
+}
+
+static yajl_callbacks parse_callbacks = {
+	NULL,
+	NULL,
+	handle_integer,
+	NULL,
+	NULL,
+	handle_string,
+	handle_start_map,
+	handle_mapkey,
+	handle_end_map,
+	NULL,
+	NULL,
+};
+
+/**
+ * Read JSON data and parse it using the given YAJL parser.
+ * @param url URL of the JSON data.
+ * @param hand YAJL parser handle.
+ * @return -1 on error, 0 on success.
+ */
+static int
+soundcloud_parse_json(const char *url, yajl_handle hand, GMutex* mutex, GCond* cond)
+{
+	struct input_stream *input_stream;
+	GError *error = NULL;
+	char buffer[4096];
+	unsigned char *ubuffer = (unsigned char *)buffer;
+	size_t nbytes;
+
+	input_stream = input_stream_open(url, mutex, cond, &error);
+	if (input_stream == NULL) {
+		if (error != NULL) {
+			g_warning("%s", error->message);
+			g_error_free(error);
+		}
+		return -1;
+	}
+
+	g_mutex_lock(mutex);
+	input_stream_wait_ready(input_stream);
+
+	yajl_status stat;
+	int done = 0;
+
+	while (!done) {
+		nbytes = input_stream_read(input_stream, buffer, sizeof(buffer), &error);
+		if (nbytes == 0) {
+			if (error != NULL) {
+				g_warning("%s", error->message);
+				g_error_free(error);
+			}
+			if (input_stream_eof(input_stream)) {
+				done = true;
+			} else {
+				g_mutex_unlock(mutex);
+				input_stream_close(input_stream);
+				return -1;
+			}
+		}
+
+		if (done)
+			stat = yajl_parse_complete(hand);
+		else
+			stat = yajl_parse(hand, ubuffer, nbytes);
+
+		if (stat != yajl_status_ok &&
+			stat != yajl_status_insufficient_data)
+		{
+			unsigned char *str = yajl_get_error(hand, 1, ubuffer, nbytes);
+			g_warning("%s", str);
+			yajl_free_error(hand, str);
+			break;
+		}
+	}
+
+	g_mutex_unlock(mutex);
+	input_stream_close(input_stream);
+
+	return 0;
+}
+
+/**
+ * Parse a soundcloud:// URL and create a playlist.
+ * @param uri A soundcloud URL. Accepted forms:
+ *	soundcloud://track/<track-id>
+ *	soundcloud://playlist/<playlist-id>
+ *	soundcloud://url/<url or path of soundcloud page>
+ */
+
+static struct playlist_provider *
+soundcloud_open_uri(const char *uri, GMutex *mutex, GCond *cond)
+{
+	struct soundcloud_playlist *playlist = NULL;
+
+	char *s, *p;
+	char *scheme, *arg, *rest;
+	s = g_strdup(uri);
+	scheme = s;
+	for (p = s; *p; p++) {
+		if (*p == ':' && *(p+1) == '/' && *(p+2) == '/') {
+			*p = 0;
+			p += 3;
+			break;
+		}
+	}
+	arg = p;
+	for (; *p; p++) {
+		if (*p == '/') {
+			*p = 0;
+			p++;
+			break;
+		}
+	}
+	rest = p;
+
+	if (strcmp(scheme, "soundcloud") != 0) {
+		g_warning("incompatible scheme for soundcloud plugin: %s", scheme);
+		g_free(s);
+		return NULL;
+	}
+
+	char *u = NULL;
+	if (strcmp(arg, "track") == 0) {
+		u = g_strconcat("http://api.soundcloud.com/tracks/",
+			rest, ".json?client_id=", soundcloud_config.apikey, NULL);
+	} else if (strcmp(arg, "playlist") == 0) {
+		u = g_strconcat("http://api.soundcloud.com/playlists/",
+			rest, ".json?client_id=", soundcloud_config.apikey, NULL);
+	} else if (strcmp(arg, "url") == 0) {
+		/* Translate to soundcloud resolver call. libcurl will automatically
+		   follow the redirect to the right resource. */
+		u = soundcloud_resolve(rest);
+	}
+	g_free(s);
+
+	if (u == NULL) {
+		g_warning("unknown soundcloud URI");
+		return NULL;
+	}
+
+	yajl_handle hand;
+	struct parse_data data;
+
+	data.got_url = 0;
+	data.songs = NULL;
+	data.title = NULL;
+	data.stream_url = NULL;
+	hand = yajl_alloc(&parse_callbacks, NULL, NULL, (void *) &data);
+
+	int ret = soundcloud_parse_json(u, hand, mutex, cond);
+
+	g_free(u);
+	yajl_free(hand);
+	if (data.title != NULL)
+		g_free(data.title);
+	if (data.stream_url != NULL)
+		g_free(data.stream_url);
+
+	if (ret == -1)
+		return NULL;
+
+	playlist = g_new(struct soundcloud_playlist, 1);
+	playlist_provider_init(&playlist->base, &soundcloud_playlist_plugin);
+	playlist->songs = g_slist_reverse(data.songs);
+
+	return &playlist->base;
+}
+
+static void
+soundcloud_close(struct playlist_provider *_playlist)
+{
+	struct soundcloud_playlist *playlist = (struct soundcloud_playlist *)_playlist;
+
+	g_free(playlist);
+}
+
+
+static struct song *
+soundcloud_read(struct playlist_provider *_playlist)
+{
+	struct soundcloud_playlist *playlist = (struct soundcloud_playlist *)_playlist;
+
+	if (playlist->songs == NULL)
+		return NULL;
+
+	struct song* s;
+	s = (struct song *)playlist->songs->data;
+	playlist->songs = g_slist_remove(playlist->songs, s);
+	return s;
+}
+
+static const char *const soundcloud_schemes[] = {
+	"soundcloud",
+	NULL
+};
+
+const struct playlist_plugin soundcloud_playlist_plugin = {
+	.name = "soundcloud",
+
+	.init = soundcloud_init,
+	.finish = soundcloud_finish,
+	.open_uri = soundcloud_open_uri,
+	.close = soundcloud_close,
+	.read = soundcloud_read,
+
+	.schemes = soundcloud_schemes,
+};
+
+
diff --git a/src/playlist/soundcloud_playlist_plugin.h b/src/playlist/soundcloud_playlist_plugin.h
new file mode 100644
index 00000000..e09e2dd4
--- /dev/null
+++ b/src/playlist/soundcloud_playlist_plugin.h
@@ -0,0 +1,25 @@
+/*
+ * 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.
+ */
+
+#ifndef MPD_PLAYLIST_SOUNDCLOUD_PLAYLIST_PLUGIN_H
+#define MPD_PLAYLIST_SOUNDCLOUD_PLAYLIST_PLUGIN_H
+
+extern const struct playlist_plugin soundcloud_playlist_plugin;
+
+#endif