output/pipewire: check pw_stream_connect() errors

src/lib/pipewire/Error.cxx

+/*
+ * Copyright 2003-2021 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 "Error.hxx"
+
+#include <spa/utils/result.h>
+
+namespace PipeWire {
+
+ErrorCategory error_category;
+
+std::string
+ErrorCategory::message(int condition) const
+{
+	return spa_strerror(condition);
+}
+
+} // namespace Avahi

src/lib/pipewire/Error.hxx

+/*
+ * Copyright 2003-2021 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.
+ */
+
+#pragma once
+
+#include <system_error>
+
+struct AvahiClient;
+
+namespace PipeWire {
+
+class ErrorCategory final : public std::error_category {
+public:
+	const char *name() const noexcept override {
+		return "pipewire";
+	}
+
+	std::string message(int condition) const override;
+};
+
+extern ErrorCategory error_category;
+
+inline std::system_error
+MakeError(int error, const char *msg) noexcept
+{
+	return std::system_error(error, error_category, msg);
+}
+
+} // namespace PipeWire

src/lib/pipewire/meson.build

@@ -12,3 +12,17 @@ pipewire_dep = declare_dependency(
   # disable it at the command line
   compile_args: ['-Wno-pedantic'],
 )
+
+pipewire = static_library(
+  'pipewire',
+  'Error.cxx',
+  include_directories: inc,
+  dependencies: [
+    pipewire_dep,
+  ],
+)
+
+pipewire_dep = declare_dependency(
+  link_with: pipewire,
+  dependencies: pipewire_dep,
+)

src/output/plugins/PipeWireOutputPlugin.cxx

@@ -18,6 +18,7 @@
  */
 
 #include "PipeWireOutputPlugin.hxx"
+#include "lib/pipewire/Error.hxx"
 #include "lib/pipewire/ThreadLoop.hxx"
 #include "../OutputAPI.hxx"
 #include "../Error.hxx"
@@ -488,14 +489,17 @@ PipeWireOutput::Open(AudioFormat &audio_format)
 	params[0] = spa_format_audio_raw_build(&pod_builder,
 					       SPA_PARAM_EnumFormat, &raw);
 
-	pw_stream_connect(stream,
-			  PW_DIRECTION_OUTPUT,
-			  target_id,
-			  (enum pw_stream_flags)(PW_STREAM_FLAG_AUTOCONNECT |
-						 PW_STREAM_FLAG_INACTIVE |
-						 PW_STREAM_FLAG_MAP_BUFFERS |
-						 PW_STREAM_FLAG_RT_PROCESS),
-			  params, 1);
+	int error =
+		pw_stream_connect(stream,
+				  PW_DIRECTION_OUTPUT,
+				  target_id,
+				  (enum pw_stream_flags)(PW_STREAM_FLAG_AUTOCONNECT |
+							 PW_STREAM_FLAG_INACTIVE |
+							 PW_STREAM_FLAG_MAP_BUFFERS |
+							 PW_STREAM_FLAG_RT_PROCESS),
+				  params, 1);
+	if (error < 0)
+		throw PipeWire::MakeError(error, "Failed to connect stream");
 }
 
 void