Move Lua reference handling into a generic base class.

stepmania/src/LuaReference.cpp

@@ -0,0 +1,124 @@
+#include "global.h"
+#include "LuaReference.h"
+#include "LuaManager.h"
+#include "LuaBinding.h"
+#include "Foreach.h"
+#include "SubscriptionManager.h"
+
+template<>
+set<LuaReference*>* SubscriptionManager<LuaReference>::s_pSubscribers = NULL;
+
+LuaReference::LuaReference()
+{
+	m_iReference = LUA_NOREF;
+	SubscriptionManager<LuaReference>::Subscribe( this );
+}
+
+LuaReference::~LuaReference()
+{
+	Unregister();
+	SubscriptionManager<LuaReference>::Unsubscribe( this );
+}
+
+LuaReference::LuaReference( const LuaReference &cpy )
+{
+	SubscriptionManager<LuaReference>::Subscribe( this );
+
+	/* Make a new reference. */
+	lua_rawgeti( LUA->L, LUA_REGISTRYINDEX, cpy.m_iReference );
+	m_iReference = luaL_ref( LUA->L, LUA_REGISTRYINDEX );
+}
+
+LuaReference &LuaReference::operator=( const LuaReference &cpy )
+{
+	if( this == &cpy )
+		return *this;
+
+	Unregister();
+
+	/* Make a new reference. */
+	lua_rawgeti( LUA->L, LUA_REGISTRYINDEX, cpy.m_iReference );
+	m_iReference = luaL_ref( LUA->L, LUA_REGISTRYINDEX );
+
+	return *this;
+}
+
+void LuaReference::SetFromStack()
+{
+	Unregister();
+
+	m_iReference = luaL_ref( LUA->L, LUA_REGISTRYINDEX );
+}
+
+void LuaReference::SetFromNil()
+{
+	Unregister();
+	m_iReference = LUA_REFNIL;
+}
+
+void LuaReference::PushSelf( lua_State *L ) const
+{
+	lua_rawgeti( LUA->L, LUA_REGISTRYINDEX, m_iReference );
+}
+
+bool LuaReference::IsSet() const
+{
+	return m_iReference != LUA_NOREF;
+}
+
+void LuaReference::Register()
+{
+}
+
+void LuaReference::Unregister()
+{
+	if( LUA == NULL )
+		return; // nothing to do
+
+	luaL_unref( LUA->L, LUA_REGISTRYINDEX, m_iReference );
+	m_iReference = LUA_NOREF;
+}
+
+void LuaReference::ReRegisterAll()
+{
+	if( SubscriptionManager<LuaReference>::s_pSubscribers == NULL )
+		return;
+	FOREACHS( LuaReference*, *SubscriptionManager<LuaReference>::s_pSubscribers, p )
+		(*p)->ReRegister();
+}
+
+void LuaReference::ReRegister()
+{
+	/* When this is called, the Lua state has been wiped.  Don't try to unregister our
+	 * old function reference, since it's already gone (and the number may point
+	 * somewhere else). */
+	m_iReference = LUA_NOREF;
+
+	Register();
+}
+
+
+/*
+ * (c) 2005 Glenn Maynard, Chris Danford
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, and/or sell copies of the Software, and to permit persons to
+ * whom the Software is furnished to do so, provided that the above
+ * copyright notice(s) and this permission notice appear in all copies of
+ * the Software and that both the above copyright notice(s) and this
+ * permission notice appear in supporting documentation.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
+ * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
+ * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
+ * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */

stepmania/src/LuaReference.h

@@ -0,0 +1,68 @@
+/* LuaReference - a self-cleaning Lua reference. */
+
+#ifndef LUA_REFERENCE_H
+#define LUA_REFERENCE_H
+
+struct lua_State;
+
+class LuaReference
+{
+public:
+	LuaReference();
+	virtual ~LuaReference();
+
+	/* Copying a reference makes a new reference pointing to the same object. */
+	LuaReference( const LuaReference &cpy );
+	LuaReference &operator=( const LuaReference &cpy );
+
+	/* Create a reference pointing to the item at the top of the stack, and pop
+	 * the stack. */
+	void SetFromStack();
+	void SetFromNil();
+
+	/* Push the referenced object onto the stack.  If not set (or set to nil), push nil. */
+	virtual void PushSelf( lua_State *L ) const;
+
+	/* Return true if set.  (SetFromNil() counts as being set.) */
+	bool IsSet() const;
+
+	static void ReRegisterAll();	// call this after resetting Lua
+
+protected:
+	/* If this object is able to recreate itself, overload this, and ReRegisterAll
+	 * will work; the reference will still exist after a theme change.  If not
+	 * implemented, the reference will be unset after ReRegister. */
+	virtual void Register();
+
+private:
+	void Unregister();
+	void ReRegister();
+	int m_iReference;
+};
+
+#endif
+
+/*
+ * (c) 2005 Glenn Maynard, Chris Danford
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, and/or sell copies of the Software, and to permit persons to
+ * whom the Software is furnished to do so, provided that the above
+ * copyright notice(s) and this permission notice appear in all copies of
+ * the Software and that both the above copyright notice(s) and this
+ * permission notice appear in supporting documentation.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
+ * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
+ * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
+ * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */