bindings: initial support for running external commands

doc/bindings

@@ -95,6 +95,9 @@
 ##      selected_items_adder, server_info, song_info,
 ##      sort_playlist_dialog, tiny_tag_editor.
 ##
+##    - run_external_command "command" - runs given command using
+##      system() function.
+##
 ## 5) In addition to binding to a key, you can also bind actions
 ##    or chains of actions to a command. If it comes to commands,
 ##    syntax is very similar to defining keys. Here goes example

src/bindings.cpp

@@ -147,6 +147,14 @@ Action *parseActionLine(const std::string &line, F error)
 			else
 				error() << "unknown action passed to require_runnable: '" << arg << "'\n";
 		}
+		else if (action_name == "run_external_command")
+		{
+			std::string command = getEnclosedString(line, '"', '"', 0);
+			if (!command.empty())
+				result = new RunExternalCommand(std::move(command));
+			else
+				error() << "empty command passed to run_external_command\n";
+		}
 	}
 	return result;
 }

src/macro_utilities.cpp

@@ -36,3 +36,9 @@ bool RequireScreen::canBeRun() const
 {
 	return Global::myScreen->type() == m_screen_type;
 }
+
+void RunExternalCommand::Run()
+{
+	GNUC_UNUSED int res;
+	res = std::system(m_command.c_str());
+}

src/macro_utilities.h

@@ -64,4 +64,16 @@ private:
 	ScreenType m_screen_type;
 };
 
+struct RunExternalCommand : public Action
+{
+	RunExternalCommand(std::string command)
+	: Action(aMacroUtility, ""), m_command(command) { }
+	
+protected:
+	virtual void Run();
+	
+private:
+	std::string m_command;
+};
+
 #endif // NCMPCPP_MACRO_UTILITIES_H