1 files changed, 183 insertions, 16 deletions

diff --git a/src/Bindings/LuaState.cpp b/src/Bindings/LuaState.cpp
index bfee1d037..2fca7142c 100644
--- a/src/Bindings/LuaState.cpp
+++ b/src/Bindings/LuaState.cpp
@@ -235,7 +235,7 @@ bool cLuaState::PushFunction(const char * a_FunctionName)
 	if (!lua_isfunction(m_LuaState, -1))
 	{
 		LOGWARNING("Error in %s: Could not find function %s()", m_SubsystemName.c_str(), a_FunctionName);
-		lua_pop(m_LuaState, 1);
+		lua_pop(m_LuaState, 2);
 		return false;
 	}
 	m_CurrentFunctionName.assign(a_FunctionName);
@@ -258,7 +258,7 @@ bool cLuaState::PushFunction(int a_FnRef)
 	lua_rawgeti(m_LuaState, LUA_REGISTRYINDEX, a_FnRef);  // same as lua_getref()
 	if (!lua_isfunction(m_LuaState, -1))
 	{
-		lua_pop(m_LuaState, 1);
+		lua_pop(m_LuaState, 2);
 		return false;
 	}
 	m_CurrentFunctionName = "<callback>";
@@ -282,7 +282,7 @@ bool cLuaState::PushFunction(const cTableRef & a_TableRef)
 	if (!lua_istable(m_LuaState, -1))
 	{
 		// Not a table, bail out
-		lua_pop(m_LuaState, 1);
+		lua_pop(m_LuaState, 2);
 		return false;
 	}
 	lua_getfield(m_LuaState, -1, a_TableRef.GetFnName());
@@ -742,6 +742,10 @@ bool cLuaState::CallFunction(int a_NumResults)
 	}
 	m_NumCurrentFunctionArgs = -1;
 	m_CurrentFunctionName.clear();
+	
+	// Remove the error handler from the stack:
+	lua_remove(m_LuaState, -a_NumResults - 1);
+	
 	return true;
 }
 
@@ -1025,21 +1029,184 @@ void cLuaState::LogStackTrace(lua_State * a_LuaState)
 
 AString cLuaState::GetTypeText(int a_StackPos)
 {
-	int Type = lua_type(m_LuaState, a_StackPos);
-	switch (Type)
+	return lua_typename(m_LuaState, lua_type(m_LuaState, a_StackPos));
+}
+
+
+
+
+
+int cLuaState::CallFunctionWithForeignParams(
+	const AString & a_FunctionName,
+	cLuaState & a_SrcLuaState,
+	int a_SrcParamStart,
+	int a_SrcParamEnd
+)
+{
+	ASSERT(IsValid());
+	ASSERT(a_SrcLuaState.IsValid());
+	
+	// Store the stack position before any changes
+	int OldTop = lua_gettop(m_LuaState);
+	
+	// Push the function to call, including the error handler:
+	if (!PushFunction(a_FunctionName.c_str()))
+	{
+		LOGWARNING("Function '%s' not found", a_FunctionName.c_str());
+		lua_pop(m_LuaState, 2);
+		return -1;
+	}
+
+	// Copy the function parameters to the target state
+	if (CopyStackFrom(a_SrcLuaState, a_SrcParamStart, a_SrcParamEnd) < 0)
 	{
-		case LUA_TNONE:          return "TNONE";
-		case LUA_TNIL:           return "TNIL";
-		case LUA_TBOOLEAN:       return "TBOOLEAN";
-		case LUA_TLIGHTUSERDATA: return "TLIGHTUSERDATA";
-		case LUA_TNUMBER:        return "TNUMBER";
-		case LUA_TSTRING:        return "TSTRING";
-		case LUA_TTABLE:         return "TTABLE";
-		case LUA_TFUNCTION:      return "TFUNCTION";
-		case LUA_TUSERDATA:      return "TUSERDATA";
-		case LUA_TTHREAD:        return "TTHREAD";
+		// Something went wrong, fix the stack and exit
+		lua_pop(m_LuaState, 2);
+		return -1;
+	}
+	
+	// Call the function, with an error handler:
+	int s = lua_pcall(m_LuaState, a_SrcParamEnd - a_SrcParamStart + 1, LUA_MULTRET, OldTop);
+	if (ReportErrors(s))
+	{
+		LOGWARN("Error while calling function '%s' in '%s'", a_FunctionName.c_str(), m_SubsystemName.c_str());
+		// Fix the stack.
+		// We don't know how many values have been pushed, so just get rid of any that weren't there initially
+		int CurTop = lua_gettop(m_LuaState);
+		if (CurTop > OldTop)
+		{
+			lua_pop(m_LuaState, CurTop - OldTop);
+		}
+		return -1;
 	}
-	return Printf("Unknown (%d)", Type);
+	
+	// Reset the internal checking mechanisms:
+	m_NumCurrentFunctionArgs = -1;
+	
+	// Remove the error handler from the stack:
+	lua_remove(m_LuaState, OldTop + 1);
+	
+	// Return the number of return values:
+	return lua_gettop(m_LuaState) - OldTop;
+}
+
+
+
+
+
+int cLuaState::CopyStackFrom(cLuaState & a_SrcLuaState, int a_SrcStart, int a_SrcEnd)
+{
+	/*
+	// DEBUG:
+	LOGD("Copying stack values from %d to %d", a_SrcStart, a_SrcEnd);
+	a_SrcLuaState.LogStack("Src stack before copying:");
+	LogStack("Dst stack before copying:");
+	*/
+	for (int i = a_SrcStart; i <= a_SrcEnd; ++i)
+	{
+		int t = lua_type(a_SrcLuaState, i);
+		switch (t)
+		{
+			case LUA_TNIL:
+			{
+				lua_pushnil(m_LuaState);
+				break;
+			}
+			case LUA_TSTRING:
+			{
+				AString s;
+				a_SrcLuaState.ToString(i, s);
+				Push(s);
+				break;
+			}
+			case LUA_TBOOLEAN:
+			{
+				bool b = (tolua_toboolean(a_SrcLuaState, i, false) != 0);
+				Push(b);
+				break;
+			}
+			case LUA_TNUMBER:
+			{
+				lua_Number d = tolua_tonumber(a_SrcLuaState, i, 0);
+				Push(d);
+				break;
+			}
+			case LUA_TUSERDATA:
+			{
+				// Get the class name:
+				const char * type = NULL;
+				if (lua_getmetatable(a_SrcLuaState, i) == 0)
+				{
+					LOGWARNING("%s: Unknown class in pos %d, cannot copy.", __FUNCTION__, i);
+					lua_pop(m_LuaState, i - a_SrcStart);
+					return -1;
+				}
+				lua_rawget(a_SrcLuaState, LUA_REGISTRYINDEX);  // Stack +1
+				type = lua_tostring(a_SrcLuaState, -1);
+				lua_pop(a_SrcLuaState, 1);                     // Stack -1
+				
+				// Copy the value:
+				void * ud = tolua_touserdata(a_SrcLuaState, i, NULL);
+				tolua_pushusertype(m_LuaState, ud, type);
+			}
+			default:
+			{
+				LOGWARNING("%s: Unsupported value: '%s' at stack position %d. Can only copy numbers, strings, bools and classes!",
+					__FUNCTION__, lua_typename(a_SrcLuaState, t), i
+				);
+				a_SrcLuaState.LogStack("Stack where copying failed:");
+				lua_pop(m_LuaState, i - a_SrcStart);
+				return -1;
+			}
+		}
+	}
+	return a_SrcEnd - a_SrcStart + 1;
+}
+
+
+
+
+
+void cLuaState::ToString(int a_StackPos, AString & a_String)
+{
+	size_t len;
+	const char * s = lua_tolstring(m_LuaState, a_StackPos, &len);
+	if (s != NULL)
+	{
+		a_String.assign(s, len);
+	}
+}
+
+
+
+
+
+void cLuaState::LogStack(const char * a_Header)
+{
+	LogStack(m_LuaState, a_Header);
+}
+
+
+
+
+
+void cLuaState::LogStack(lua_State * a_LuaState, const char * a_Header)
+{
+	LOGD((a_Header != NULL) ? a_Header : "Lua C API Stack contents:");
+	for (int i = lua_gettop(a_LuaState); i >= 0; i--)
+	{
+		AString Value;
+		int Type = lua_type(a_LuaState, i);
+		switch (Type)
+		{
+			case LUA_TBOOLEAN: Value.assign((lua_toboolean(a_LuaState, i) != 0) ? "true" : "false"); break;
+			case LUA_TLIGHTUSERDATA: Printf(Value, "%p", lua_touserdata(a_LuaState, i)); break;
+			case LUA_TNUMBER:        Printf(Value, "%f", (double)lua_tonumber(a_LuaState, i)); break;
+			case LUA_TSTRING:        Printf(Value, "%s", lua_tostring(a_LuaState, i)); break;
+			default: break;
+		}
+		LOGD("  Idx %d: type %d (%s) %s", i, Type, lua_typename(a_LuaState, Type), Value.c_str());
+	}  // for i - stack idx
 }