From d558f166f9e45378b7adb96bf9328234035b386d Mon Sep 17 00:00:00 2001
From: maelstrom <maelstrom@maelstrom.dev>
Date: Thu, 10 Jul 2025 02:03:35 +0200
Subject: [PATCH] fix(lua): segfault on error handler, new error handler system
 adopted

---
 core/src/objects/script.cpp                   | 70 ++++++++++---------
 .../objects/service/script/scriptcontext.cpp  | 23 +-----
 .../objects/service/script/scriptcontext.h    |  3 -
 3 files changed, 37 insertions(+), 59 deletions(-)

diff --git a/core/src/objects/script.cpp b/core/src/objects/script.cpp
index 217bbdc..86a975c 100644
--- a/core/src/objects/script.cpp
+++ b/core/src/objects/script.cpp
@@ -13,6 +13,8 @@
 
 int script_wait(lua_State*);
 int script_delay(lua_State*);
+int script_wrapper(lua_State*);
+int script_errhandler(lua_State*);
 
 Script::Script(): Instance(&TYPE) {
     source = "print(\"Hello, world!\")";
@@ -52,41 +54,11 @@ void Script::Run() {
 
     lua_pop(Lt, 1); // _G
 
-    // Load source and push onto thread stack as function ptr
-    // luaL_loadstring(Lt, source.c_str());
-    luaL_loadbuffer(Lt, source.c_str(), source.size(), scriptContext->RegisterScriptSource(shared<Script>()).c_str());
-    
-    int status = lua_resume(Lt, 0);
-    if (status > LUA_YIELD) {
-        lua_Debug dbg;
-        lua_getstack(Lt, 1, &dbg);
-        lua_getinfo(Lt, "S", &dbg);
+    // Load source and push onto thread stack as upvalue for wrapper closure
+    luaL_loadbuffer(Lt, source.c_str(), source.size(), this->GetFullName().c_str());
+    lua_pushcclosure(Lt, script_wrapper, 1);
 
-        std::weak_ptr<Script> source = scriptContext->GetScriptFromSource(dbg.source);
-
-        std::string errorMessage = lua_tostring(Lt, -1);
-        if (!source.expired())
-            errorMessage = source.lock()->GetFullName() + errorMessage.substr(errorMessage.find(':'));
-
-        Logger::error(errorMessage);
-        lua_pop(Lt, 1); // Pop return value
-
-        Logger::traceStart();
-
-        int stack = 1;
-        while (lua_getstack(Lt, stack++, &dbg)) {
-            lua_getinfo(Lt, "nlSu", &dbg);
-            
-            std::weak_ptr<Script> source = scriptContext->GetScriptFromSource(dbg.source);
-            if (source.expired()) {
-                Logger::trace(dbg.source, dbg.currentline);
-            } else {
-                Logger::trace(source.lock()->GetFullName(), dbg.currentline, &source);
-            }
-        }
-
-        Logger::traceEnd();
-    }
+    lua_resume(Lt, 0);
 
     lua_pop(L, 1); // Pop the thread
 }
@@ -121,5 +93,35 @@ int script_delay(lua_State* L) {
     // Schedule next run
     scriptContext->PushThreadSleep(Lt, secs);
 
+    return 0;
+}
+
+int script_wrapper(lua_State* L) {
+    lua_pushcfunction(L, script_errhandler);
+    lua_pushvalue(L, lua_upvalueindex(1));
+    lua_pcall(L, 0, 0, -2);
+    return 0;
+}
+
+int script_errhandler(lua_State* L) {
+    std::string errorMessage = lua_tostring(L, -1);
+    Logger::error(errorMessage);
+
+    // Traceback
+
+    Logger::traceStart();
+
+    lua_Debug dbg;
+    int stack = 1;
+    while (lua_getstack(L, stack++, &dbg)) {
+        lua_getinfo(L, "nlSu", &dbg);
+        if (strcmp(dbg.what, "C") == 0)
+            continue; // Ignore C frames
+
+        Logger::trace(dbg.source, dbg.currentline);
+    }
+
+    Logger::traceEnd();
+    
     return 0;
 }
\ No newline at end of file
diff --git a/core/src/objects/service/script/scriptcontext.cpp b/core/src/objects/service/script/scriptcontext.cpp
index 176286c..358e3a8 100644
--- a/core/src/objects/service/script/scriptcontext.cpp
+++ b/core/src/objects/service/script/scriptcontext.cpp
@@ -105,11 +105,7 @@ void ScriptContext::RunSleepingThreads() {
             // Time args
             lua_pushnumber(sleep.thread, float(tu_clock_micros() - sleep.timeYieldedWhen) / 1'000'000);
             lua_pushnumber(sleep.thread, float(tu_clock_micros()) / 1'000'000);
-            int status = lua_resume(sleep.thread, 2);
-            if (status > LUA_YIELD) {
-                Logger::error(lua_tostring(sleep.thread, -1));
-                lua_pop(sleep.thread, 1); // Pop return value
-            }
+            lua_resume(sleep.thread, 2);
 
             // Remove thread
             deleted = true;
@@ -134,23 +130,6 @@ void ScriptContext::RunSleepingThreads() {
         schedTime = tu_clock_micros() - startTime;
 }
 
-std::string ScriptContext::RegisterScriptSource(std::shared_ptr<Script> script) {
-    // If it has already been registered, reference it here
-    for (auto& [id, script2] : scriptSources) {
-        if (!script2.expired() && script2.lock() == script)
-            return "=f" + std::to_string(id);
-    }
-
-    int id = lastScriptSourceId++;
-    scriptSources[id] = script;
-    return "=f" + std::to_string(id);
-}
-
-std::weak_ptr<Script> ScriptContext::GetScriptFromSource(std::string source) {
-    int id = std::stoi(source.c_str() + 2);
-    return scriptSources[id];
-}
-
 // https://www.lua.org/source/5.1/lbaselib.c.html
 static int g_print(lua_State* L) {
     std::string buf;
diff --git a/core/src/objects/service/script/scriptcontext.h b/core/src/objects/service/script/scriptcontext.h
index 8177dac..89407b4 100644
--- a/core/src/objects/service/script/scriptcontext.h
+++ b/core/src/objects/service/script/scriptcontext.h
@@ -19,7 +19,6 @@ class DEF_INST_SERVICE ScriptContext : public Service {
     AUTOGEN_PREAMBLE
 
     std::vector<SleepingThread> sleepingThreads;
-    std::map<int, std::weak_ptr<Script>> scriptSources;
     int lastScriptSourceId = 0;
 protected:
     void InitService() override;
@@ -32,8 +31,6 @@ public:
     lua_State* state;
     void PushThreadSleep(lua_State* thread, float delay);
     void RunSleepingThreads();
-    std::string RegisterScriptSource(std::shared_ptr<Script>);
-    std::weak_ptr<Script> GetScriptFromSource(std::string source);
 
     static inline std::shared_ptr<Instance> Create() { return std::make_shared<ScriptContext>(); };
 };
\ No newline at end of file