From 99cd354a16f4ec550ba3a2a50b40b0d95985c49d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tam=C3=A1s=20B=C3=A1lint=20Misius?= <lbphacker@gmail.com>
Date: Mon, 25 Mar 2024 20:49:00 +0100
Subject: [PATCH] Fix dialuges looping infinitely in some cases

Namely, when no completion callback is specified, they use themselves, of all things, as their completion callback, because lua_gettop returns 0 and somehow Lua is ok with that stack index and thinks it refers to the function being executed.
---
 src/lua/LuaInterface.cpp | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/lua/LuaInterface.cpp b/src/lua/LuaInterface.cpp
index e38992a15..4e8af47a9 100644
--- a/src/lua/LuaInterface.cpp
+++ b/src/lua/LuaInterface.cpp
@@ -50,7 +50,10 @@ static int beginMessageBox(lua_State *L)
 	auto message = PickIfType(L, 2, String("Message"));
 	auto large = PickIfType(L, 3, false);
 	auto cb = std::make_shared<LuaSmartRef>(); // * Bind to main lua state (might be different from L).
-	cb->Assign(L, lua_gettop(L));
+	if (lua_gettop(L))
+	{
+		cb->Assign(L, lua_gettop(L));
+	}
 	new InformationMessage(title, message, large, { [cb]() {
 		auto *lsi = GetLSI();
 		auto L = lsi->L;
@@ -74,7 +77,10 @@ static int beginThrowError(lua_State *L)
 {
 	auto errorMessage = PickIfType(L, 1, String("Error text"));
 	auto cb = std::make_shared<LuaSmartRef>(); // * Bind to main lua state (might be different from L).
-	cb->Assign(L, lua_gettop(L));
+	if (lua_gettop(L))
+	{
+		cb->Assign(L, lua_gettop(L));
+	}
 	new ErrorMessage("Error", errorMessage, { [cb]() {
 		auto *lsi = GetLSI();
 		auto L = lsi->L;
@@ -101,7 +107,10 @@ static int beginInput(lua_State *L)
 	auto text = PickIfType(L, 3, String(""));
 	auto shadow = PickIfType(L, 4, String(""));
 	auto cb = std::make_shared<LuaSmartRef>(); // * Bind to main lua state (might be different from L).
-	cb->Assign(L, lua_gettop(L));
+	if (lua_gettop(L))
+	{
+		cb->Assign(L, lua_gettop(L));
+	}
 	auto handle = [cb](std::optional<String> input) {
 		auto *lsi = GetLSI();
 		auto L = lsi->L;
@@ -140,7 +149,10 @@ static int beginConfirm(lua_State *L)
 	auto message = PickIfType(L, 2, String("Message"));
 	auto buttonText = PickIfType(L, 3, String("Confirm"));
 	auto cb = std::make_shared<LuaSmartRef>(); // * Bind to main lua state (might be different from L).
-	cb->Assign(L, lua_gettop(L));
+	if (lua_gettop(L))
+	{
+		cb->Assign(L, lua_gettop(L));
+	}
 	auto handle = [cb](int result) {
 		auto *lsi = GetLSI();
 		auto L = lsi->L;