input/tidal: add exception class TidalError

Allows catchers to inspect the HTTP status.

Makefile.am

@@ -1372,6 +1372,7 @@ endif
 if ENABLE_TIDAL
 libinput_a_SOURCES += \
 	$(YAJL_SOURCES) \
+	src/input/plugins/TidalError.hxx \
 	src/input/plugins/TidalErrorParser.cxx src/input/plugins/TidalErrorParser.hxx \
 	src/input/plugins/TidalLoginRequest.cxx src/input/plugins/TidalLoginRequest.hxx \
 	src/input/plugins/TidalSessionManager.cxx src/input/plugins/TidalSessionManager.hxx \

src/input/plugins/TidalError.hxx

@@ -0,0 +1,47 @@
+/*
+ * 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_ERROR_HXX
+#define TIDAL_ERROR_HXX
+
+#include "check.h"
+
+#include <stdexcept>
+
+/**
+ * An error condition reported by the server.
+ */
+class TidalError : public std::runtime_error {
+	/**
+	 * The HTTP status code.
+	 */
+	unsigned status;
+
+public:
+	template<typename W>
+	TidalError(unsigned _status, W &&_what) noexcept
+		:std::runtime_error(std::forward<W>(_what)),
+		 status(_status) {}
+
+	unsigned GetStatus() const noexcept {
+		return status;
+	}
+};
+
+#endif

src/input/plugins/TidalErrorParser.cxx

@@ -19,6 +19,7 @@
 
 #include "config.h"
 #include "TidalErrorParser.hxx"
+#include "TidalError.hxx"
 #include "lib/yajl/Callbacks.hxx"
 #include "util/ConstBuffer.hxx"
 #include "util/RuntimeError.hxx"
@@ -53,11 +54,15 @@ TidalErrorParser::OnEnd()
 {
 	YajlResponseParser::OnEnd();
 
+	char what[1024];
+
 	if (!message.empty())
-		throw FormatRuntimeError("Error from Tidal: %s",
+		snprintf(what, sizeof(what), "Error from Tidal: %s",
-					 message.c_str());
+			 message.c_str());
 	else
-		throw FormatRuntimeError("Status %u from Tidal", status);
+		snprintf(what, sizeof(what), "Status %u from Tidal", status);
+
+	throw TidalError(status, what);
 }
 
 inline bool

src/input/plugins/TidalErrorParser.hxx

@@ -30,7 +30,8 @@ template<typename T> struct ConstBuffer;
 struct StringView;
 
 /**
- * Parse an error JSON response.
+ * Parse an error JSON response and throw a #TidalError upon
+ * completion.
  */
 class TidalErrorParser final : public YajlResponseParser {
 	const unsigned status;