input/tidal: new input plugin to receive Tidal streams

Makefile.am

@@ -1366,6 +1366,16 @@ libinput_a_SOURCES += \
 	src/IcyMetaDataParser.cxx src/IcyMetaDataParser.hxx
 endif
 
+if ENABLE_TIDAL
+libinput_a_SOURCES += \
+	$(YAJL_SOURCES) \
+	src/input/plugins/TidalLoginRequest.cxx src/input/plugins/TidalLoginRequest.hxx \
+	src/input/plugins/TidalSessionManager.cxx src/input/plugins/TidalSessionManager.hxx \
+	src/input/plugins/TidalTrackRequest.cxx src/input/plugins/TidalTrackRequest.hxx \
+	src/input/plugins/TidalInputPlugin.cxx src/input/plugins/TidalInputPlugin.hxx
+INPUT_LIBS += $(YAJL_LIBS)
+endif
+
 if ENABLE_SMBCLIENT
 libinput_a_SOURCES += \
 	$(SMBCLIENT_SOURCES) \

NEWS

@@ -5,6 +5,8 @@ ver 0.21 (not yet released)
   - "outputs" prints the plugin name
   - "outputset" sets runtime attributes
   - close connection when client sends HTTP request
+* input
+  - tidal: new plugin to play Tidal streams
 * tags
   - new tags "OriginalDate", "MUSICBRAINZ_WORKID"
 * decoder

configure.ac

@@ -367,6 +367,11 @@ AC_ARG_ENABLE(soundcloud,
 		[enable support for soundcloud.com]),,
 	[enable_soundcloud=auto])
 
+AC_ARG_ENABLE(tidal,
+	AS_HELP_STRING([--enable-tidal],
+		[enable support for Tidal streaming]),,
+	[enable_tidal=auto])
+
 AC_ARG_ENABLE([libwrap],
 	AS_HELP_STRING([--enable-libwrap], [use libwrap]),,
 	[enable_libwrap=auto])
@@ -562,7 +567,7 @@ MPD_ENABLE_AUTO_PKG(expat, EXPAT, [expat],
 
 dnl -------------------------------- yajl -------------------------------------
 
-if test x$enable_soundcloud != xno; then
+if test x$enable_soundcloud != xno || test x$enable_tidal != xno; then
 	PKG_CHECK_MODULES([YAJL], [yajl >= 2.0],
 		[found_yajl=yes],
 		[found_yajl=no])
@@ -700,6 +705,7 @@ dnl Input Plugins
 dnl ---------------------------------------------------------------------------
 
 dnl ----------------------------------- CURL ----------------------------------
+
 MPD_ENABLE_AUTO_PKG(curl, CURL, [libcurl >= 7.18],
 	[libcurl HTTP streaming], [libcurl not found])
 
@@ -718,6 +724,12 @@ MPD_DEPENDS([enable_soundcloud], [found_yajl],
 MPD_DEFINE_CONDITIONAL(enable_soundcloud, ENABLE_SOUNDCLOUD,
 	[soundcloud.com support])
 
+dnl --------------------------------- Tidal -----------------------------------
+MPD_DEPENDS([enable_tidal], [found_yajl], [Tidal streaming], [libyajl not found])
+MPD_DEPENDS([enable_tidal], [enable_curl], [Tidal streaming], [libcurl not found])
+MPD_AUTO(tidal, [Tidal streaming], [Tidal not available], [found_tidal=yes])
+MPD_DEFINE_CONDITIONAL(enable_tidal, ENABLE_TIDAL, [Tidal streaming])
+
 dnl ---------------------------------- cdio ---------------------------------
 MPD_ENABLE_AUTO_PKG(cdio_paranoia, CDIO_PARANOIA, [libcdio_paranoia],
 	[libcdio_paranoia input plugin], [libcdio_paranoia not found])
@@ -1515,6 +1527,7 @@ results(cdio_paranoia, [CDIO_PARANOIA])
 results(curl,[CURL])
 results(smbclient,[SMBCLIENT])
 results(soundcloud,[Soundcloud])
+results(tidal,[Tidal])
 printf '\n\t'
 results(mms,[MMS])
 

doc/user.xml

@@ -2369,6 +2369,60 @@ run</programlisting>
           <filename>mpc add smb://servername/sharename/filename.ogg</filename>
         </para>
       </section>
+
+      <section id="tidal_input">
+        <title><varname>tidal</varname></title>
+
+        <para>
+          Play songs from the commercial streaming service <ulink
+          url="http://tidal.com/">Tidal</ulink>.  It plays URLs in the
+          form <filename>tidal://track/ID</filename>, e.g.:
+        </para>
+
+        <programlisting>mpc add tidal://track/59727857</programlisting>
+
+        <informaltable>
+          <tgroup cols="2">
+            <thead>
+              <row>
+                <entry>Setting</entry>
+                <entry>Description</entry>
+              </row>
+            </thead>
+            <tbody>
+              <row>
+                <entry>
+                  <varname>token</varname>
+                  <parameter>TOKEN</parameter>
+                </entry>
+                <entry>
+                  The Tidal application token.
+                </entry>
+              </row>
+
+              <row>
+                <entry>
+                  <varname>username</varname>
+                  <parameter>USERNAME</parameter>
+                </entry>
+                <entry>
+                  The Tidal user name.
+                </entry>
+              </row>
+
+              <row>
+                <entry>
+                  <varname>password</varname>
+                  <parameter>PASSWORD</parameter>
+                </entry>
+                <entry>
+                  The Tidal password.
+                </entry>
+              </row>
+            </tbody>
+          </tgroup>
+        </informaltable>
+      </section>
     </section>
 
     <section id="decoder_plugins">

src/input/Registry.cxx

@@ -21,6 +21,7 @@
 #include "Registry.hxx"
 #include "util/Macros.hxx"
 #include "plugins/FileInputPlugin.hxx"
+#include "plugins/TidalInputPlugin.hxx"
 
 #ifdef ENABLE_ALSA
 #include "plugins/AlsaInputPlugin.hxx"
@@ -62,6 +63,9 @@ const InputPlugin *const input_plugins[] = {
 #ifdef ENABLE_ARCHIVE
 	&input_plugin_archive,
 #endif
+#ifdef ENABLE_TIDAL
+	&tidal_input_plugin,
+#endif
 #ifdef ENABLE_CURL
 	&input_plugin_curl,
 #endif

src/input/plugins/TidalInputPlugin.cxx

@@ -0,0 +1,174 @@
+/*
+ * Copyright 2003-2018 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 "TidalInputPlugin.hxx"
+#include "TidalSessionManager.hxx"
+#include "TidalTrackRequest.hxx"
+#include "CurlInputPlugin.hxx"
+#include "PluginUnavailable.hxx"
+#include "input/ProxyInputStream.hxx"
+#include "input/FailingInputStream.hxx"
+#include "input/InputPlugin.hxx"
+#include "config/Block.hxx"
+#include "thread/Mutex.hxx"
+#include "util/StringCompare.hxx"
+
+#include <stdexcept>
+#include <memory>
+
+static TidalSessionManager *tidal_session;
+
+class TidalInputStream final
+	: public ProxyInputStream, TidalSessionHandler, TidalTrackHandler {
+
+	const std::string track_id;
+
+	std::unique_ptr<TidalTrackRequest> track_request;
+
+	std::exception_ptr error;
+
+public:
+	TidalInputStream(const char *_uri, const char *_track_id,
+			 Mutex &_mutex, Cond &_cond) noexcept
+		:ProxyInputStream(_uri, _mutex, _cond),
+		 track_id(_track_id)
+	{
+		tidal_session->AddLoginHandler(*this);
+	}
+
+	~TidalInputStream() {
+		tidal_session->RemoveLoginHandler(*this);
+	}
+
+	/* virtual methods from InputStream */
+
+	void Check() override {
+		if (error)
+			std::rethrow_exception(error);
+	}
+
+private:
+	void Failed(std::exception_ptr e) {
+		SetInput(std::make_unique<FailingInputStream>(GetURI(), e,
+							      mutex, cond));
+	}
+
+	/* virtual methods from TidalSessionHandler */
+	void OnTidalSession() noexcept override;
+
+	/* virtual methods from TidalTrackHandler */
+	void OnTidalTrackSuccess(std::string &&url) noexcept override;
+	void OnTidalTrackError(std::exception_ptr error) noexcept override;
+};
+
+void
+TidalInputStream::OnTidalSession() noexcept
+{
+	const std::lock_guard<Mutex> protect(mutex);
+
+	try {
+		TidalTrackHandler &handler = *this;
+		track_request = std::make_unique<TidalTrackRequest>(tidal_session->GetCurl(),
+								    tidal_session->GetBaseUrl(),
+								    tidal_session->GetToken(),
+								    tidal_session->GetSession().c_str(),
+								    track_id.c_str(),
+								    handler);
+	} catch (...) {
+		Failed(std::current_exception());
+	}
+}
+
+void
+TidalInputStream::OnTidalTrackSuccess(std::string &&url) noexcept
+{
+	const std::lock_guard<Mutex> protect(mutex);
+
+	try {
+		SetInput(OpenCurlInputStream(url.c_str(), {},
+					     mutex, cond));
+	} catch (...) {
+		Failed(std::current_exception());
+	}
+}
+
+void
+TidalInputStream::OnTidalTrackError(std::exception_ptr e) noexcept
+{
+	const std::lock_guard<Mutex> protect(mutex);
+
+	Failed(e);
+}
+
+static void
+InitTidalInput(EventLoop &event_loop, const ConfigBlock &block)
+{
+	const char *base_url = block.GetBlockValue("base_url",
+						   "https://api.tidal.com/v1");
+
+	const char *token = block.GetBlockValue("token");
+	if (token == nullptr)
+		throw PluginUnavailable("No Tidal application token configured");
+
+	const char *username = block.GetBlockValue("username");
+	if (username == nullptr)
+		throw PluginUnavailable("No Tidal username configured");
+
+	const char *password = block.GetBlockValue("password");
+	if (password == nullptr)
+		throw PluginUnavailable("No Tidal password configured");
+
+	// TODO: "audioquality" setting
+
+	tidal_session = new TidalSessionManager(event_loop, base_url, token,
+						username, password);
+}
+
+static void
+FinishTidalInput()
+{
+	delete tidal_session;
+}
+
+static InputStreamPtr
+OpenTidalInput(const char *uri, Mutex &mutex, Cond &cond)
+{
+	assert(tidal_session != nullptr);
+
+	const char *track_id;
+
+	track_id = StringAfterPrefix(uri, "tidal://track/");
+	if (track_id == nullptr)
+		track_id = StringAfterPrefix(uri, "https://listen.tidal.com/track/");
+
+	if (track_id == nullptr || *track_id == 0)
+		return nullptr;
+
+	// TODO: validate track_id
+
+	return std::make_unique<TidalInputStream>(uri, track_id, mutex, cond);
+}
+
+const InputPlugin tidal_input_plugin = {
+	"tidal",
+	InitTidalInput,
+	FinishTidalInput,
+	OpenTidalInput,
+};

src/input/plugins/TidalInputPlugin.hxx

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2003-2018 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 INPUT_TIDAL_HXX
+#define INPUT_TIDAL_HXX
+
+extern const struct InputPlugin tidal_input_plugin;
+
+#endif

src/input/plugins/TidalLoginRequest.cxx

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2003-2018 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 "TidalLoginRequest.hxx"
+#include "lib/curl/Form.hxx"
+#include "lib/yajl/Callbacks.hxx"
+#include "util/RuntimeError.hxx"
+
+using Wrapper = Yajl::CallbacksWrapper<TidalLoginRequest>;
+static constexpr yajl_callbacks parse_callbacks = {
+	nullptr,
+	nullptr,
+	nullptr,
+	nullptr,
+	nullptr,
+	Wrapper::String,
+	nullptr,
+	Wrapper::MapKey,
+	Wrapper::EndMap,
+	nullptr,
+	nullptr,
+};
+
+static std::string
+MakeLoginUrl(const char *base_url)
+{
+	return std::string(base_url) + "/login/username";
+}
+
+TidalLoginRequest::TidalLoginRequest(CurlGlobal &curl,
+				     const char *base_url, const char *token,
+				     const char *username, const char *password,
+				     TidalLoginHandler &_handler) noexcept
+	:request(curl, MakeLoginUrl(base_url).c_str(), *this),
+	 parser(&parse_callbacks, nullptr, this),
+	 handler(_handler)
+{
+	request_headers.Append((std::string("X-Tidal-Token:")
+				+ token).c_str());
+	request.SetOption(CURLOPT_HTTPHEADER, request_headers.Get());
+
+	request.SetOption(CURLOPT_COPYPOSTFIELDS,
+			  EncodeForm(request.Get(),
+				     {{"username", username}, {"password", password}}).c_str());
+
+	request.StartIndirect();
+}
+
+TidalLoginRequest::~TidalLoginRequest() noexcept
+{
+	request.StopIndirect();
+}
+
+void
+TidalLoginRequest::OnHeaders(unsigned status,
+			     std::multimap<std::string, std::string> &&headers)
+{
+	if (status != 200)
+		throw FormatRuntimeError("Status %u from Tidal", status);
+
+	auto i = headers.find("content-type");
+	if (i == headers.end() || i->second.find("/json") == i->second.npos)
+		throw std::runtime_error("Not a JSON response from Tidal");
+}
+
+void
+TidalLoginRequest::OnData(ConstBuffer<void> data)
+{
+	parser.Parse((const unsigned char *)data.data, data.size);
+}
+
+void
+TidalLoginRequest::OnEnd()
+{
+	parser.CompleteParse();
+
+	if (session.empty())
+		throw std::runtime_error("No sessionId in login response");
+
+	handler.OnTidalLoginSuccess(std::move(session));
+}
+
+void
+TidalLoginRequest::OnError(std::exception_ptr e) noexcept
+{
+	handler.OnTidalLoginError(e);
+}
+
+inline bool
+TidalLoginRequest::String(StringView value) noexcept
+{
+	switch (state) {
+	case State::NONE:
+		break;
+
+	case State::SESSION_ID:
+		session.assign(value.data, value.size);
+		break;
+	}
+
+	return true;
+}
+
+inline bool
+TidalLoginRequest::MapKey(StringView value) noexcept
+{
+	if (value.Equals("sessionId"))
+		state = State::SESSION_ID;
+	else
+		state = State::NONE;
+
+	return true;
+}
+
+inline bool
+TidalLoginRequest::EndMap() noexcept
+{
+	state = State::NONE;
+
+	return true;
+}

src/input/plugins/TidalLoginRequest.hxx

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2003-2018 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 TIDAL_LOGIN_REQUEST_HXX
+#define TIDAL_LOGIN_REQUEST_HXX
+
+#include "check.h"
+#include "lib/curl/Handler.hxx"
+#include "lib/curl/Slist.hxx"
+#include "lib/curl/Request.hxx"
+#include "lib/yajl/Handle.hxx"
+
+#include <exception>
+#include <string>
+
+class CurlRequest;
+
+class TidalLoginHandler {
+public:
+	virtual void OnTidalLoginSuccess(std::string &&session) noexcept = 0;
+	virtual void OnTidalLoginError(std::exception_ptr error) noexcept = 0;
+};
+
+class TidalLoginRequest final : CurlResponseHandler {
+	CurlSlist request_headers;
+
+	CurlRequest request;
+
+	Yajl::Handle parser;
+
+	enum class State {
+		NONE,
+		SESSION_ID,
+	} state = State::NONE;
+
+	std::string session;
+
+	std::exception_ptr error;
+
+	TidalLoginHandler &handler;
+
+public:
+	TidalLoginRequest(CurlGlobal &curl,
+			  const char *base_url, const char *token,
+			  const char *username, const char *password,
+			  TidalLoginHandler &_handler) noexcept;
+
+	~TidalLoginRequest() noexcept;
+
+private:
+	/* virtual methods from CurlResponseHandler */
+	void OnHeaders(unsigned status,
+		       std::multimap<std::string, std::string> &&headers) override;
+	void OnData(ConstBuffer<void> data) override;
+	void OnEnd() override;
+	void OnError(std::exception_ptr e) noexcept override;
+
+public:
+	/* yajl callbacks */
+	bool String(StringView value) noexcept;
+	bool MapKey(StringView value) noexcept;
+	bool EndMap() noexcept;
+};
+
+#endif

src/input/plugins/TidalSessionManager.cxx

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2003-2018 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 "TidalSessionManager.hxx"
+#include "lib/curl/Global.hxx"
+
+TidalSessionManager::TidalSessionManager(EventLoop &event_loop,
+					 const char *_base_url, const char *_token,
+					 const char *_username,
+					 const char *_password) noexcept
+	:base_url(_base_url), token(_token),
+	 username(_username), password(_password),
+	 curl(event_loop),
+	 defer_invoke_handlers(event_loop,
+			       BIND_THIS_METHOD(InvokeHandlers))
+{
+}
+
+TidalSessionManager::~TidalSessionManager() noexcept
+{
+	assert(handlers.empty());
+}
+
+void
+TidalSessionManager::AddLoginHandler(TidalSessionHandler &h) noexcept
+{
+	const std::lock_guard<Mutex> protect(mutex);
+	assert(!h.is_linked());
+
+	const bool was_empty = handlers.empty();
+	handlers.push_front(h);
+
+	if (was_empty && session.empty() && !login_request) {
+		// TODO: throttle login attempts?
+
+		std::string login_uri(base_url);
+		login_uri += "/login/username";
+
+		try {
+			TidalLoginHandler &handler = *this;
+			login_request =
+				std::make_unique<TidalLoginRequest>(*curl, base_url,
+								    token,
+								    username, password,
+								    handler);
+		} catch (...) {
+			error = std::current_exception();
+			ScheduleInvokeHandlers();
+			return;
+		}
+	}
+}
+
+void
+TidalSessionManager::OnTidalLoginSuccess(std::string &&_session) noexcept
+{
+	{
+		const std::lock_guard<Mutex> protect(mutex);
+		session = std::move(_session);
+	}
+
+	ScheduleInvokeHandlers();
+}
+
+void
+TidalSessionManager::OnTidalLoginError(std::exception_ptr e) noexcept
+{
+	{
+		const std::lock_guard<Mutex> protect(mutex);
+		error = e;
+	}
+
+	ScheduleInvokeHandlers();
+}
+
+void
+TidalSessionManager::InvokeHandlers() noexcept
+{
+	const std::lock_guard<Mutex> protect(mutex);
+	while (!handlers.empty()) {
+		auto &h = handlers.front();
+		handlers.pop_front();
+
+		const ScopeUnlock unlock(mutex);
+		h.OnTidalSession();
+	}
+
+	login_request.reset();
+}

src/input/plugins/TidalSessionManager.hxx

@@ -0,0 +1,144 @@
+/*
+ * Copyright 2003-2018 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 TIDAL_SESSION_MANAGER_HXX
+#define TIDAL_SESSION_MANAGER_HXX
+
+#include "check.h"
+#include "TidalLoginRequest.hxx"
+#include "lib/curl/Init.hxx"
+#include "thread/Mutex.hxx"
+#include "event/DeferEvent.hxx"
+
+#include <boost/intrusive/list.hpp>
+
+#include <memory>
+#include <string>
+
+class CurlRequest;
+class TidalLoginRequest;
+
+class TidalSessionHandler
+	: public boost::intrusive::list_base_hook<boost::intrusive::link_mode<boost::intrusive::safe_link>>
+{
+public:
+	virtual void OnTidalSession() noexcept = 0;
+};
+
+class TidalSessionManager final : TidalLoginHandler {
+	/**
+	 * The Tidal API base URL.
+	 */
+	const char *const base_url;
+
+	/**
+	 * The configured Tidal application token.
+	 */
+	const char *const token;
+
+	/**
+	 * The configured Tidal user name.
+	 */
+	const char *const username;
+
+	/**
+	 * The configured Tidal password.
+	 */
+	const char *const password;
+
+	CurlInit curl;
+
+	DeferEvent defer_invoke_handlers;
+
+	/**
+	 * Protects #session, #error and #handlers.
+	 */
+	mutable Mutex mutex;
+
+	std::exception_ptr error;
+
+	/**
+	 * The current Tidal session id, empty if none.
+	 */
+	std::string session;
+
+	typedef boost::intrusive::list<TidalSessionHandler,
+				       boost::intrusive::constant_time_size<false>> LoginHandlerList;
+
+	LoginHandlerList handlers;
+
+	std::unique_ptr<TidalLoginRequest> login_request;
+
+public:
+	TidalSessionManager(EventLoop &event_loop,
+			    const char *_base_url, const char *_token,
+			    const char *_username,
+			    const char *_password) noexcept;
+
+	~TidalSessionManager() noexcept;
+
+	EventLoop &GetEventLoop() noexcept {
+		return defer_invoke_handlers.GetEventLoop();
+	}
+
+	CurlGlobal &GetCurl() noexcept {
+		return *curl;
+	}
+
+	const char *GetBaseUrl() const noexcept {
+		return base_url;
+	}
+
+	void AddLoginHandler(TidalSessionHandler &h) noexcept;
+
+	void RemoveLoginHandler(TidalSessionHandler &h) noexcept {
+		const std::lock_guard<Mutex> protect(mutex);
+		if (h.is_linked())
+			handlers.erase(handlers.iterator_to(h));
+	}
+
+	const char *GetToken() const noexcept {
+		return token;
+	}
+
+	std::string GetSession() const {
+		const std::lock_guard<Mutex> protect(mutex);
+
+		if (error)
+			std::rethrow_exception(error);
+
+		if (session.empty())
+			throw std::runtime_error("No session");
+
+		return session;
+	}
+
+private:
+	void InvokeHandlers() noexcept;
+
+	void ScheduleInvokeHandlers() noexcept {
+		defer_invoke_handlers.Schedule();
+	}
+
+	/* virtual methods from TidalLoginHandler */
+	void OnTidalLoginSuccess(std::string &&session) noexcept override;
+	void OnTidalLoginError(std::exception_ptr error) noexcept override;
+};
+
+#endif

src/input/plugins/TidalTrackRequest.cxx

@@ -0,0 +1,141 @@
+/*
+ * Copyright 2003-2018 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 "TidalTrackRequest.hxx"
+#include "lib/yajl/Callbacks.hxx"
+#include "util/RuntimeError.hxx"
+
+using Wrapper = Yajl::CallbacksWrapper<TidalTrackRequest>;
+static constexpr yajl_callbacks parse_callbacks = {
+	nullptr,
+	nullptr,
+	nullptr,
+	nullptr,
+	nullptr,
+	Wrapper::String,
+	nullptr,
+	Wrapper::MapKey,
+	Wrapper::EndMap,
+	nullptr,
+	nullptr,
+};
+
+static std::string
+MakeTrackUrl(const char *base_url, const char *track_id)
+{
+	// TODO: add "audioquality" parameter to this function
+	return std::string(base_url)
+		+ "/tracks/"
+		+ track_id
+		+ "/urlpostpaywall?assetpresentation=FULL&audioquality=LOW&urlusagemode=STREAM";
+}
+
+TidalTrackRequest::TidalTrackRequest(CurlGlobal &curl,
+				     const char *base_url, const char *token,
+				     const char *session,
+				     const char *track_id,
+				     TidalTrackHandler &_handler) noexcept
+	:request(curl, MakeTrackUrl(base_url, track_id).c_str(), *this),
+	 parser(&parse_callbacks, nullptr, this),
+	 handler(_handler)
+{
+	request_headers.Append((std::string("X-Tidal-Token:")
+				+ token).c_str());
+	request_headers.Append((std::string("X-Tidal-SessionId:")
+				+ session).c_str());
+	request.SetOption(CURLOPT_HTTPHEADER, request_headers.Get());
+
+	request.StartIndirect();
+}
+
+TidalTrackRequest::~TidalTrackRequest() noexcept
+{
+	request.StopIndirect();
+}
+
+void
+TidalTrackRequest::OnHeaders(unsigned status,
+			     std::multimap<std::string, std::string> &&headers)
+{
+	if (status != 200)
+		throw FormatRuntimeError("Status %u from Tidal", status);
+
+	auto i = headers.find("content-type");
+	if (i == headers.end() || i->second.find("/json") == i->second.npos)
+		throw std::runtime_error("Not a JSON response from Tidal");
+}
+
+void
+TidalTrackRequest::OnData(ConstBuffer<void> data)
+{
+	parser.Parse((const unsigned char *)data.data, data.size);
+}
+
+void
+TidalTrackRequest::OnEnd()
+{
+	parser.CompleteParse();
+
+	if (url.empty())
+		throw std::runtime_error("No url in track response");
+
+	handler.OnTidalTrackSuccess(std::move(url));
+}
+
+void
+TidalTrackRequest::OnError(std::exception_ptr e) noexcept
+{
+	handler.OnTidalTrackError(e);
+}
+
+inline bool
+TidalTrackRequest::String(StringView value) noexcept
+{
+	switch (state) {
+	case State::NONE:
+		break;
+
+	case State::URLS:
+		if (url.empty())
+			url.assign(value.data, value.size);
+		break;
+	}
+
+	return true;
+}
+
+inline bool
+TidalTrackRequest::MapKey(StringView value) noexcept
+{
+	if (value.Equals("urls"))
+		state = State::URLS;
+	else
+		state = State::NONE;
+
+	return true;
+}
+
+inline bool
+TidalTrackRequest::EndMap() noexcept
+{
+	state = State::NONE;
+
+	return true;
+}

src/input/plugins/TidalTrackRequest.hxx

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2003-2018 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 TIDAL_TRACK_REQUEST_HXX
+#define TIDAL_TRACK_REQUEST_HXX
+
+#include "check.h"
+#include "lib/curl/Handler.hxx"
+#include "lib/curl/Slist.hxx"
+#include "lib/curl/Request.hxx"
+#include "lib/yajl/Handle.hxx"
+
+#include <exception>
+#include <string>
+
+class CurlRequest;
+
+class TidalTrackHandler
+	: public boost::intrusive::list_base_hook<boost::intrusive::link_mode<boost::intrusive::safe_link>>
+{
+public:
+	virtual void OnTidalTrackSuccess(std::string &&url) noexcept = 0;
+	virtual void OnTidalTrackError(std::exception_ptr error) noexcept = 0;
+};
+
+class TidalTrackRequest final : CurlResponseHandler {
+	CurlSlist request_headers;
+
+	CurlRequest request;
+
+	Yajl::Handle parser;
+
+	enum class State {
+		NONE,
+		URLS,
+	} state = State::NONE;
+
+	std::string url;
+
+	std::exception_ptr error;
+
+	TidalTrackHandler &handler;
+
+public:
+	TidalTrackRequest(CurlGlobal &curl,
+			  const char *base_url, const char *token,
+			  const char *session,
+			  const char *track_id,
+			  TidalTrackHandler &_handler) noexcept;
+
+	~TidalTrackRequest() noexcept;
+
+private:
+	/* virtual methods from CurlResponseHandler */
+	void OnHeaders(unsigned status,
+		       std::multimap<std::string, std::string> &&headers) override;
+	void OnData(ConstBuffer<void> data) override;
+	void OnEnd() override;
+	void OnError(std::exception_ptr e) noexcept override;
+
+public:
+	/* yajl callbacks */
+	bool String(StringView value) noexcept;
+	bool MapKey(StringView value) noexcept;
+	bool EndMap() noexcept;
+};
+
+#endif

src/ls.cxx

@@ -60,6 +60,9 @@ static const char *const remoteUrlPrefixes[] = {
 #endif
 #ifdef ENABLE_ALSA
 	"alsa://",
+#endif
+#ifdef ENABLE_TIDAL
+	"tidal://",
 #endif
 	NULL
 };