private void pushObject(Object o)
{
GCHandle gch = GCHandle.Alloc(o);
// Store the GCHandle so that it won't get garbage collected.
mLuaReferences.Add(gch);
// Push a userdata onto the stack (we don't care about the returned address)
// This is needed because we cannot create a metatable for a lightuserdata.
// So we make the light userdata a member of it's metatable.
IntPtr p = LuaDll.lua_newuserdata(L, 8);
// Write the IntPtr of the object handle to the userdata.
Marshal.WriteIntPtr(p, GCHandle.ToIntPtr(gch));
// Pushes the metatable of the given class onto the stack
pushMetatable(o.GetType());
// We should have a metatable of this object's class on the top of the stack.
// Now register the object, which is below that (-2)
// o.__metatable = mt
LuaDll.lua_setmetatable(L, -2);
// The exported object should now be on the top of the stack.
}
/// <summary>
/// Returns the value at stack index i as a C# object.
/// </summary>
/// <param name="i">Index of object</param>
/// <returns>Returns object at index i</returns>
private object getValue(int i)
{
object result = null;
int t = LuaDll.lua_type(L, i);
switch (t)
{
case LuaDll.LUA_TSTRING: /* strings */
result = LuaDll.lua_tostring(L, i);
break;
case LuaDll.LUA_TBOOLEAN: /* booleans */
result = LuaDll.lua_toboolean(L, i);
break;
case LuaDll.LUA_TNUMBER: /* numbers */
result = LuaDll.lua_tonumber(L, i);
break;
case LuaDll.LUA_TUSERDATA: /* user data */
IntPtr p = LuaDll.lua_touserdata(L, i);
result = GCHandle.FromIntPtr(Marshal.ReadIntPtr(p)).Target;
break;
default: /* other values */
Console.WriteLine("getValue({0}) : Unsupported type [{1}]", i, LuaDll.lua_typename(L, t));
break;
}
return(result);
}
private int pushFunctionLut(System.Reflection.MethodInfo mi, string bindName)
{
int top = LuaDll.lua_gettop(L);
// Push global lut to the stack
string globalLutName = "__Lua.cs__LUT__";
LuaDll.lua_getfield(L, LuaDll.LUA_REGISTRYINDEX, globalLutName);
if (LuaDll.lua_isnil(L, -1))
{
// If the global lut does not exist then create it and push it onto the stack.
// Pop the nil value
LuaDll.lua_pop(L, 1);
// Push a new table and set it as the global globalLutName
LuaDll.lua_newtable(L);
LuaDll.lua_pushvalue(L, -1); // Dupe for setglobal call.
LuaDll.lua_setfield(L, LuaDll.LUA_REGISTRYINDEX, globalLutName);
}
int lut = LuaDll.lua_gettop(L);
Debug.Assert(lut == (top + 1));
// Push function lut to the stack.
string fullName = mi.ReflectedType.FullName + "." + bindName;
LuaDll.lua_getfield(L, lut, fullName);
if (LuaDll.lua_isnil(L, -1))
{
// If the function lut does not exist then create it.
// Pop off the nil result.
LuaDll.lua_pop(L, 1);
// Push in a new table
LuaDll.lua_newtable(L);
// Add the name to the table as kFunctionNameKey
LuaDll.lua_pushstring(L, bindName);
LuaDll.lua_setfield(L, -2, kFunctionNameKey);
// Add this to the global lut, keyed on FullName
LuaDll.lua_pushvalue(L, -1);
LuaDll.lua_setfield(L, lut, fullName);
}
// Remove the global lut
LuaDll.lua_remove(L, lut);
// Now we have the function lut at the top of the stack.
int result = LuaDll.lua_gettop(L);
Debug.Assert(result == top + 1);
// Return the stack position of the lut.
return(result);
}
/// <summary>
/// Pushes the object v into the lua stack and returns the number of values that were pushed.
/// If v is a MultiValue then it might push more than one value.
/// Will automatically register the class of the object if not yet registered
/// </summary>
/// <param name="v">Object to push onto the stack</param>
/// <returns></returns>
private int pushValue(object v)
{
if (v == null)
{
return(0);
}
Type t = v.GetType();
if (t == typeof(int))
{
LuaDll.lua_pushinteger(L, (int)v);
return(1);
}
else if ((t == typeof(double)) || (t == typeof(float)))
{
LuaDll.lua_pushnumber(L, (double)v);
return(1);
}
else if (t == typeof(string))
{
LuaDll.lua_pushstring(L, (string)v);
return(1);
}
else if (t == typeof(bool))
{
LuaDll.lua_pushboolean(L, ((bool)v)?1:0);
return(1);
}
else if (t == typeof(MultiValue))
{
// Special case to push multiple values onto the stack
MultiValue mv = (MultiValue)v;
int result = 0;
for (int i = 0; i < mv.Length; ++i)
{
// Since this is recursive, we could end up with arrays inside arrays.
// Should we catch that?
result += pushValue(mv[i]);
}
return(result);
}
else if (t.IsClass)
{
// If the is an object, then store a reference to it in the static
// list of lua references. It can be removed from this list once
// lua is done with it.
pushObject(v);
return(1);
}
else
{
// Error, unexpected type, cannot push.
Console.WriteLine("pushValue() Cannot push type [{0}]", t.FullName);
return(0);
}
}
private void registerFunctionAs(System.Reflection.MethodInfo mi, string name)
{
// Push the function delgate
pushFunction(mi, name);
// Set the function as a global in the lua scope with the same name.
LuaDll.lua_setglobal(L, name);
}
public void registerObject(string name, Object o)
{
// Push the object onto the stack (this will also register the class as needed)
pushObject(o);
// Now set the object (which is now at the top of the stack) to be a global
// with the given name.
LuaDll.lua_setglobal(L, name);
}
private void registerClass(Type t)
{
string className = t.FullName;
if (LuaDll.luaL_newmetatable(L, className) == 1)
{
int top = LuaDll.lua_gettop(L);
Console.WriteLine("Registering class " + className);
foreach (System.Reflection.MethodInfo mi in t.GetMethods())
{
if (mi.IsPublic)
{
// Check that this method has been declared as bindable?
if (isBindable(mi))
{
// If the name is set, then bind using that name.
string bindName = getBindableName(mi, mi.Name);
// Push the method
pushFunction(mi, bindName);
// Set the pushed closure as a member of our table.
// The method should be at the top of the stack (-1), and the table below that (-2)
// mt[mi.Name] = method;
LuaDll.lua_setfield(L, -2, bindName);
}
}
}
// Register some luaisms
// __gc
LuaDll.lua_pushcfunction(L, mgcAdapterDelegate);
LuaDll.lua_setfield(L, -2, "__gc");
// __tostring
LuaDll.lua_pushcfunction(L, mtostringAdapterDelegate);
LuaDll.lua_setfield(L, -2, "__tostring");
// __eq
// Comparison operator
LuaDll.lua_pushcfunction(L, meqAdapterDelegate);
LuaDll.lua_setfield(L, -2, "__eq");
LuaDll.lua_pushstring(L, "__index"); // Push "__index"
LuaDll.lua_pushvalue(L, -2); // Copy the metatable to the top of the stack
LuaDll.lua_settable(L, -3); // mt["__index"] = mt
// metatable should be at top of stack.
Debug.Assert(top == LuaDll.lua_gettop(L), "Top is wrong");
}
}
/// <summary>
/// Implementation of __tostring metamethod.
/// Used to convert a userdata object to a string for printing.
/// </summary>
/// <param name="L">Lua state</param>
/// <returns>Returns one string on the stack</returns>
private int tostringAdapter(lua_State L)
{
// Get the object
IntPtr ud = LuaDll.lua_touserdata(L, 1);
GCHandle gh = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud));
// Generate the string result
string result = String.Format("{0}: {1:X}", gh.Target.ToString(), ud.ToInt32());
// Push the string and return it (return 1)
LuaDll.lua_pushstring(L, result);
return(1);
}
/// <summary>
/// Implementation of __eq metamethod.
/// This is used to compare two objects of the same type for equality.
/// </summary>
/// <param name="L">Lua state</param>
/// <returns>Returns 0 on the stack if the arguments are not equal, 1 otherwise</returns>
private int eqAdapter(lua_State L)
{
// Get the objects
IntPtr ud1 = LuaDll.lua_touserdata(L, 1);
GCHandle gh1 = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud1));
IntPtr ud2 = LuaDll.lua_touserdata(L, 2);
GCHandle gh2 = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud2));
bool result = gh1.Target.Equals(gh2.Target);
LuaDll.lua_pushboolean(L, result ? 1 : 0);
return(1);
}
/// <summary>
/// Implementation of __gc metamethod.
/// Called when a userdata object is being released by the lua garbage collector.
/// </summary>
/// <param name="L">Lua state</param>
/// <returns>Returns 0</returns>
private int gcAdapter(lua_State L)
{
// Remove the referenced object from the global reference list so that
// it can be cleaned up by the GC.
IntPtr ud = LuaDll.lua_touserdata(L, 1);
GCHandle gh = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud));
Console.WriteLine("[gcAdapter] - Releasing " + gh.Target.ToString());
bool result = mLuaReferences.Remove(gh);
Debug.Assert(result, "[gcAdapter] - garbage collector release object not in mLuaReferences");
return(0);
}
public MultiValue dostring(string s)
{
int top = LuaDll.lua_gettop(L);
int ret = LuaDll.luaL_dostring(L, s);
if (ret != 0)
{
string err = LuaDll.lua_tostring(L, -1);
Console.WriteLine("ERROR: " + err);
LuaDll.lua_pop(L, 1);
}
else
{
int newtop = LuaDll.lua_gettop(L);
return(getValues(top + 1, newtop - top));
}
return(null);
}
///////////////////////////////////////////////////////////////////////
/// <summary>
/// Constructor - creates a new lua state.
/// </summary>
public LuaState()
{
mLuaFunctionCallAdapterDelegate = functionCallAdapter;
mgcAdapterDelegate = gcAdapter;
mtostringAdapterDelegate = tostringAdapter;
meqAdapterDelegate = eqAdapter;
L = LuaDll.luaL_newstate();
LuaDll.luaL_openlibs(L);
LuaDll.lua_atpanic(L, mPanicFunctionDelegate);
// Redirect stderr from the Lua DLL to an error file.
//FileStream fs = new FileStream("error.txt", FileMode.Create);
//mOutputRef = new HandleRef(fs, fs.Handle);
//SetStdHandle(-12, mOutputRef);
// Install a new print function (to capture stdout)
LuaDll.lua_register(L, "print", sLuaPrintDelegate);
}
private void pushFunction(System.Reflection.MethodInfo mi, string bindName)
{
int top = LuaDll.lua_gettop(L);
// Generate unique name based on parameter list.
string mangle = buildMangledNameFromMethodInfo(mi, bindName);
// Push the Look Up Table for this function onto the Lua stack.
int flut = pushFunctionLut(mi, bindName);
// Lookup the manged name.
LuaDll.lua_getfield(L, flut, mangle);
// If not already defined then go ahead and define it
if (LuaDll.lua_isnil(L, -1))
{
// Pop nil value
LuaDll.lua_pop(L, 1);
// Store the function in a GCHandle in a global list so it
// doesn't get garbage collected.
GCHandle h = GCHandle.Alloc(mi);
mLuaReferences.Add(h);
// functionLut[mangledName] = MethodInfo
LuaDll.lua_pushlightuserdata(L, GCHandle.ToIntPtr(h));
LuaDll.lua_setfield(L, flut, mangle);
// Push the function call delegate with the function lut as an up value.
LuaDll.lua_pushcclosure(L, mLuaFunctionCallAdapterDelegate, 1);
}
else
{
System.Reflection.MethodInfo oldMi = (System.Reflection.MethodInfo)GCHandle.FromIntPtr(LuaDll.lua_touserdata(L, -1)).Target;
throw new Exception(String.Format("Duplicate function registration of '{0}', old={1}, new={2}", demangleName(mangle), oldMi, mi));
}
Debug.Assert(LuaDll.lua_gettop(L) == top + 1);
}
public void inspectClass(Object o)
{
int top = LuaDll.lua_gettop(L);
// check if this class is registered and inspect the metatable
LuaDll.luaL_getmetatable(L, o.GetType().FullName);
if (LuaDll.lua_isnil(L, -1))
{
Console.WriteLine("inspectClass - metatable not found for class [{0}]", o.GetType().FullName);
return;
}
Console.WriteLine("Inspecting {0}", o.GetType().FullName);
/* table is in the stack at index 't' */
int t = LuaDll.lua_gettop(L);
LuaDll.lua_pushnil(L); /* first key */
while (LuaDll.lua_next(L, t) != 0)
{
// Use built-in "print" function to print the two values on the stack.
LuaDll.lua_getglobal(L, "print");
LuaDll.lua_pushstring(L, "\t");
LuaDll.lua_pushvalue(L, -4);
LuaDll.lua_pushvalue(L, -4);
LuaDll.lua_call(L, 3, 0);
/* removes 'value'; keeps 'key' for next iteration */
LuaDll.lua_pop(L, 1);
}
// Pop the metatable
LuaDll.lua_pop(L, 1);
Debug.Assert(top == LuaDll.lua_gettop(L), "Error in stack");
}
/// <summary>
/// Build a mangled name from a lua function call.
/// Assumes that the function arguments are on the stack.
/// This is to allow each unique overloaded method in C# to have a unique name in lua.
/// Method names must be in the same format generated by buildMangledNameFromMethodInfo.
/// </summary>
/// <param name="simpleName">Unmangled name of method</param>
/// <returns>Returns a string containing a unique name of the given method</returns>
/// <see>buildMangledNameFromMethodInfo</see>
private string buildMangledNameFromLuaParameters(string simpleName)
{
StringBuilder sb = new StringBuilder(simpleName + "_");
int paramcount = LuaDll.lua_gettop(L);
Type[] types = new Type[paramcount];
for (int i = 0; i < paramcount; ++i)
{
int luaType = LuaDll.lua_type(L, i + 1);
switch (luaType)
{
case LuaDll.LUA_TBOOLEAN:
sb.Append("b");
break;
case LuaDll.LUA_TNUMBER:
sb.Append("n");
break;
case LuaDll.LUA_TSTRING:
sb.Append("s");
break;
case LuaDll.LUA_TUSERDATA:
sb.Append("c");
break;
default:
Console.WriteLine("Invalid parameter #{0} as {1}", i + 1, LuaDll.lua_typename(L, luaType));
break;
}
}
return(sb.ToString());
}
public MultiValue call(string func, params object[] args)
{
int top = LuaDll.lua_gettop(L);
MultiValue mv = new MultiValue(args);
LuaDll.lua_getfield(L, LuaDll.LUA_GLOBALSINDEX, func);
int count = pushValue(mv);
int ret = LuaDll.lua_pcall(L, count, LuaDll.LUA_MULTRET, 0);
if (ret != 0)
{
string err = LuaDll.lua_tostring(L, -1);
Console.WriteLine("ERROR: " + err);
LuaDll.lua_pop(L, 1);
}
else
{
int newtop = LuaDll.lua_gettop(L);
return(getValues(top + 1, newtop - top));
}
return(null);
}
/// <summary>
/// Single lua function used for all C# function or method calls from lua.
/// </summary>
/// <param name="L">Lua state</param>
/// <returns>Returns number of results pushed onto the stack</returns>
private int functionCallAdapter(lua_State L)
{
// Figure out which function to call.
// Our upvalue is a table of all methods with the same name as this one.
// Get the function name.
LuaDll.lua_getfield(L, LuaDll.lua_upvalueindex(1), kFunctionNameKey);
string simpleName = LuaDll.lua_tostring(L, -1);
LuaDll.lua_pop(L, 1);
// Lookup the mangled name from the lut stored at upvalueindex.
string mangledName = buildMangledNameFromLuaParameters(simpleName);
LuaDll.lua_getfield(L, LuaDll.lua_upvalueindex(1), mangledName);
if (LuaDll.lua_isnil(L, -1))
{
LuaDll.luaL_error(L, "Unknown function " + mangledName + " \"" + demangleName(mangledName) + "\"");
return(0);
}
// Get the function delegate from the stack.
GCHandle h = GCHandle.FromIntPtr(LuaDll.lua_topointer(L, -1));
LuaDll.lua_pop(L, 1);
System.Reflection.MethodInfo fd = (System.Reflection.MethodInfo)h.Target;
System.Reflection.ParameterInfo[] pinfo = fd.GetParameters();
int firstParam = 0;
Object self = null;
// Check if this is a static method or not. If it is not static, then the first
// parameter must be an instance of the class.
if (!fd.IsStatic)
{
// Get the pointer to the object (and verify the type).
IntPtr ud = LuaDll.luaL_checkudata(L, 1, fd.ReflectedType.FullName);
// Copy the address of the object from the userdata.
GCHandle hSelf = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud));
// Since this is a non-static method, it will have an extra parameter.
firstParam = 1;
self = hSelf.Target;
}
// Verify that we are getting the correct number of parameters
if (pinfo.Length != (LuaDll.lua_gettop(L) - firstParam))
{
LuaDll.luaL_error(L, "Invalid number of parameters for function '{0}'", fd.Name);
return(1);
}
Object[] parms = new Object[pinfo.Length];
int firstLuaParam = firstParam + 1;
for (int i = 0; i < pinfo.Length; ++i)
{
if (pinfo[i].ParameterType == typeof(int))
{
parms[i] = LuaDll.luaL_checkinteger(L, i + firstLuaParam);
}
else if (pinfo[i].ParameterType == typeof(double))
{
parms[i] = LuaDll.luaL_checknumber(L, i + firstLuaParam);
}
else if (pinfo[i].ParameterType == typeof(string))
{
parms[i] = LuaDll.luaL_checkstring(L, i + firstLuaParam);
}
else if (pinfo[i].ParameterType == typeof(bool))
{
LuaDll.luaL_checktype(L, i + firstLuaParam, LuaDll.LUA_TBOOLEAN);
parms[i] = LuaDll.lua_toboolean(L, i + firstLuaParam);
}
else
{
// Get the pointer to the object.
IntPtr ud = LuaDll.lua_touserdata(L, i + firstLuaParam);
parms[i] = GCHandle.FromIntPtr(Marshal.ReadIntPtr(ud)).Target;
}
}
object result = fd.Invoke(self, parms);
return(pushValue(result));
}
