i wish i couldve done it right the first time

desmume/src/commandline.cpp

@@ -0,0 +1,91 @@
+/*  commandline.cpp
+
+    Copyright (C) 2009 DeSmuME team
+
+    This file is part of DeSmuME
+
+    DeSmuME 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.
+
+    DeSmuME 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 DeSmuME; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
+*/
+
+#include <glib.h>
+
+#include <stdio.h>
+#include "commandline.h"
+
+CommandLine::CommandLine()
+: error(NULL)
+, ctx(g_option_context_new (""))
+{
+	load_slot = 0;
+}
+
+CommandLine::~CommandLine()
+{
+	if(error) g_error_free (error);
+	g_option_context_free (ctx);
+}
+
+void CommandLine::loadCommonOptions()
+{
+	//these options should be available in every port.
+	//my advice is, do not be afraid of using #ifdef here if it makes sense.
+	//but also see the gtk port for an example of how to combine this with other options
+	//(you may need to use ifdefs to cause options to be entered in the desired order)
+	static const GOptionEntry options[] = {
+		{ "load-slot", 0, 0, G_OPTION_ARG_INT, &load_slot, "Loads savegame from slot NUM", "NUM"},
+		{ NULL }
+	};
+
+	g_option_context_add_main_entries (ctx, options, "options");
+}
+
+bool CommandLine::parse(int argc,char **argv)
+{
+	g_option_context_parse (ctx, &argc, &argv, &error);
+	if (error)
+	{
+		g_printerr("Error parsing command line arguments: %s\n", error->message);
+		return false;
+	}
+
+	if (argc == 2)
+		nds_file = argv[1];
+	if (argc > 2)
+		return false;
+
+	return true;
+}
+
+bool CommandLine::validate()
+{
+	if (load_slot < 0 || load_slot > 10) {
+		g_printerr("I only know how to load from slots 1-10, 0 means 'do not load savegame' and is default\n");
+		return false;
+	}
+
+	return true;
+}
+
+void CommandLine::errorHelp(const char* binName)
+{
+	//TODO - strip this down to just the filename
+	g_printerr("USAGE: %s [options] [nds-file]\n", binName);
+	g_printerr("USAGE: %s --help    - for help\n", binName);
+}
+
+void foo()
+{
+	g_option_context_free(NULL);
+}

desmume/src/commandline.h

@@ -0,0 +1,60 @@
+/*  commandline.h
+
+    Copyright (C) 2009 DeSmuME team
+
+    This file is part of DeSmuME
+
+    DeSmuME 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.
+
+    DeSmuME 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 DeSmuME; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
+*/
+
+#ifndef _COMMANDLINE_H_
+#define _COMMANDLINE_H_
+
+#include <string>
+
+//I hate C. we have to forward declare these with more detail than I like
+typedef struct _GOptionContext GOptionContext;
+typedef struct _GError GError;
+
+//this class will also eventually try to take over the responsibility of using the args that it handles
+//for example: preparing the emulator run by loading the rom, savestate, and/or movie in the correct pattern.
+//it should also populate CommonSettings with its initial values
+
+class CommandLine
+{
+public:
+	//actual options: these may move to another sturct
+	int load_slot;
+	std::string nds_file;
+
+	//load up the common commandline options
+	void loadCommonOptions();
+	
+	bool parse(int argc,char **argv);
+
+	//validate the common commandline options
+	bool validate();
+	
+	//print a little help message for cases when erroneous commandlines are entered
+	void errorHelp(const char* binName);
+
+	CommandLine();
+	~CommandLine();
+
+	GOptionContext *ctx;
+	GError *error;
+};
+
+#endif