1 files changed, 401 insertions, 0 deletions
diff --git a/src/playlist/plugins/SoundCloudPlaylistPlugin.cxx b/src/playlist/plugins/SoundCloudPlaylistPlugin.cxx
new file mode 100644
index 000000000..ec4d240a5
--- /dev/null
+++ b/src/playlist/plugins/SoundCloudPlaylistPlugin.cxx
@@ -0,0 +1,401 @@
+/*
+ * Copyright (C) 2003-2014 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 "SoundCloudPlaylistPlugin.hxx"
+#include "../PlaylistPlugin.hxx"
+#include "../MemorySongEnumerator.hxx"
+#include "config/ConfigData.hxx"
+#include "input/InputStream.hxx"
+#include "tag/TagBuilder.hxx"
+#include "util/StringUtil.hxx"
+#include "util/Error.hxx"
+#include "util/Domain.hxx"
+#include "Log.hxx"
+
+#include <glib.h>
+#include <yajl/yajl_parse.h>
+
+#include <string>
+
+#include <string.h>
+
+static struct {
+	std::string apikey;
+} soundcloud_config;
+
+static constexpr Domain soundcloud_domain("soundcloud");
+
+static bool
+soundcloud_init(const config_param &param)
+{
+	// APIKEY for MPD application, registered under DarkFox' account.
+	soundcloud_config.apikey = param.GetBlockValue("apikey", "a25e51780f7f86af0afa91f241d091f8");
+	if (soundcloud_config.apikey.empty()) {
+		LogDebug(soundcloud_domain,
+			 "disabling the soundcloud playlist plugin "
+			 "because API key is not set");
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * 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 (StringStartsWith(uri, "https://")) {
+		u = g_strdup(uri);
+	} else if (StringStartsWith(uri, "soundcloud.com")) {
+		u = g_strconcat("https://", uri, nullptr);
+	} else {
+		/* assume it's just a path on soundcloud.com */
+		u = g_strconcat("https://soundcloud.com/", uri, nullptr);
+	}
+
+	ru = g_strconcat("https://api.soundcloud.com/resolve.json?url=",
+			 u, "&client_id=",
+			 soundcloud_config.apikey.c_str(), nullptr);
+	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",
+	nullptr,
+};
+
+struct parse_data {
+	int key;
+	char* stream_url;
+	long duration;
+	char* title;
+	int got_url; /* nesting level of last stream_url */
+
+	std::forward_list<DetachedSong> songs;
+};
+
+static int
+handle_integer(void *ctx,
+	       long
+#ifndef HAVE_YAJL1
+	       long
+#endif
+	       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,
+#ifdef HAVE_YAJL1
+	      unsigned int
+#else
+	      size_t
+#endif
+	      stringlen)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+	const char *s = (const char *) stringval;
+
+	switch (data->key) {
+	case Title:
+		g_free(data->title);
+		data->title = g_strndup(s, stringlen);
+		break;
+	case Stream_URL:
+		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,
+#ifdef HAVE_YAJL1
+	      unsigned int
+#else
+	      size_t
+#endif
+	      stringlen)
+{
+	struct parse_data *data = (struct parse_data *) ctx;
+
+	int i;
+	data->key = Other;
+
+	for (i = 0; i < Other; ++i) {
+		if (memcmp((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;
+
+	char *u = g_strconcat(data->stream_url, "?client_id=",
+			      soundcloud_config.apikey.c_str(), nullptr);
+
+	TagBuilder tag;
+	tag.SetDuration(SignedSongTime::FromMS(data->duration));
+	if (data->title != nullptr)
+		tag.AddItem(TAG_NAME, data->title);
+
+	data->songs.emplace_front(u, tag.Commit());
+	g_free(u);
+
+	return 1;
+}
+
+static yajl_callbacks parse_callbacks = {
+	nullptr,
+	nullptr,
+	handle_integer,
+	nullptr,
+	nullptr,
+	handle_string,
+	handle_start_map,
+	handle_mapkey,
+	handle_end_map,
+	nullptr,
+	nullptr,
+};
+
+/**
+ * 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,
+		      Mutex &mutex, Cond &cond)
+{
+	Error error;
+	InputStream *input_stream = InputStream::OpenReady(url, mutex, cond,
+							   error);
+	if (input_stream == nullptr) {
+		if (error.IsDefined())
+			LogError(error);
+		return -1;
+	}
+
+	mutex.lock();
+
+	yajl_status stat;
+	int done = 0;
+
+	while (!done) {
+		char buffer[4096];
+		unsigned char *ubuffer = (unsigned char *)buffer;
+		const size_t nbytes =
+			input_stream->Read(buffer, sizeof(buffer), error);
+		if (nbytes == 0) {
+			if (error.IsDefined())
+				LogError(error);
+
+			if (input_stream->IsEOF()) {
+				done = true;
+			} else {
+				mutex.unlock();
+				delete input_stream;
+				return -1;
+			}
+		}
+
+		if (done) {
+#ifdef HAVE_YAJL1
+			stat = yajl_parse_complete(hand);
+#else
+			stat = yajl_complete_parse(hand);
+#endif
+		} else
+			stat = yajl_parse(hand, ubuffer, nbytes);
+
+		if (stat != yajl_status_ok
+#ifdef HAVE_YAJL1
+		    && stat != yajl_status_insufficient_data
+#endif
+		    )
+		{
+			unsigned char *str = yajl_get_error(hand, 1, ubuffer, nbytes);
+			LogError(soundcloud_domain, (const char *)str);
+			yajl_free_error(hand, str);
+			break;
+		}
+	}
+
+	mutex.unlock();
+	delete 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 SongEnumerator *
+soundcloud_open_uri(const char *uri, Mutex &mutex, Cond &cond)
+{
+	assert(memcmp(uri, "soundcloud://", 13) == 0);
+	uri += 13;
+
+	char *u = nullptr;
+	if (memcmp(uri, "track/", 6) == 0) {
+		const char *rest = uri + 6;
+		u = g_strconcat("https://api.soundcloud.com/tracks/",
+				rest, ".json?client_id=",
+				soundcloud_config.apikey.c_str(), nullptr);
+	} else if (memcmp(uri, "playlist/", 9) == 0) {
+		const char *rest = uri + 9;
+		u = g_strconcat("https://api.soundcloud.com/playlists/",
+				rest, ".json?client_id=",
+				soundcloud_config.apikey.c_str(), nullptr);
+	} else if (memcmp(uri, "user/", 5) == 0) {
+		const char *rest = uri + 5;
+		u = g_strconcat("https://api.soundcloud.com/users/",
+				rest, "/tracks.json?client_id=",
+				soundcloud_config.apikey.c_str(), nullptr);
+	} else if (memcmp(uri, "search/", 7) == 0) {
+		const char *rest = uri + 7;
+		u = g_strconcat("https://api.soundcloud.com/tracks.json?q=",
+				rest, "&client_id=",
+				soundcloud_config.apikey.c_str(), nullptr);
+	} else if (memcmp(uri, "url/", 4) == 0) {
+		const char *rest = uri + 4;
+		/* Translate to soundcloud resolver call. libcurl will automatically
+		   follow the redirect to the right resource. */
+		u = soundcloud_resolve(rest);
+	}
+
+	if (u == nullptr) {
+		LogWarning(soundcloud_domain, "unknown soundcloud URI");
+		return nullptr;
+	}
+
+	struct parse_data data;
+	data.got_url = 0;
+	data.title = nullptr;
+	data.stream_url = nullptr;
+#ifdef HAVE_YAJL1
+	yajl_handle hand = yajl_alloc(&parse_callbacks, nullptr, nullptr,
+				      &data);
+#else
+	yajl_handle hand = yajl_alloc(&parse_callbacks, nullptr, &data);
+#endif
+
+	int ret = soundcloud_parse_json(u, hand, mutex, cond);
+
+	g_free(u);
+	yajl_free(hand);
+	g_free(data.title);
+	g_free(data.stream_url);
+
+	if (ret == -1)
+		return nullptr;
+
+	data.songs.reverse();
+	return new MemorySongEnumerator(std::move(data.songs));
+}
+
+static const char *const soundcloud_schemes[] = {
+	"soundcloud",
+	nullptr
+};
+
+const struct playlist_plugin soundcloud_playlist_plugin = {
+	"soundcloud",
+
+	soundcloud_init,
+	nullptr,
+	soundcloud_open_uri,
+	nullptr,
+
+	soundcloud_schemes,
+	nullptr,
+	nullptr,
+};
+
+