From 148a2bdb457441f6d79e69cafb92366de22177b8 Mon Sep 17 00:00:00 2001
From: bjorn <tie.372@gmail.com>
Date: Wed, 26 Sep 2018 10:39:17 -0700
Subject: [PATCH] Error system no longer relies on Lua;

---
 src/api/thread.c |  3 ++-
 src/lovr.c       |  4 +++-
 src/luax.c       |  6 ++++++
 src/luax.h       |  1 +
 src/util.c       | 33 ++++++++++++++++++++++-----------
 src/util.h       |  6 +++++-
 6 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/src/api/thread.c b/src/api/thread.c
index d4a994d4..96858eef 100644
--- a/src/api/thread.c
+++ b/src/api/thread.c
@@ -12,8 +12,9 @@ static int threadRunner(void* data) {
   mtx_unlock(&thread->lock);
 
   // Lua state
-  lua_State* L = lovrErrorContext = luaL_newstate();
+  lua_State* L = luaL_newstate();
   luaL_openlibs(L);
+  lovrSetErrorCallback((lovrErrorHandler) luax_vthrow, L);
   l_lovrInit(L);
   lua_setglobal(L, "lovr");
 
diff --git a/src/lovr.c b/src/lovr.c
index b0f2834a..948b42a3 100644
--- a/src/lovr.c
+++ b/src/lovr.c
@@ -82,9 +82,11 @@ void lovrDestroy() {
 }
 
 bool lovrRun(int argc, char** argv, int* status) {
-  lua_State* L = lovrErrorContext = luaL_newstate();
+  lua_State* L = luaL_newstate();
   luaL_openlibs(L);
 
+  lovrSetErrorCallback((lovrErrorHandler) luax_vthrow, L);
+
   glfwSetErrorCallback(onGlfwError);
   lovrAssert(glfwInit(), "Error initializing GLFW");
   glfwSetTime(0);
diff --git a/src/luax.c b/src/luax.c
index dda6aa4f..ec9e83ad 100644
--- a/src/luax.c
+++ b/src/luax.c
@@ -1,6 +1,7 @@
 #include "luax.h"
 #include "util.h"
 #include <stdlib.h>
+#include <stdarg.h>
 
 static int luax_meta__tostring(lua_State* L) {
   lua_getfield(L, -1, "name");
@@ -163,6 +164,11 @@ void luax_pushobject(lua_State* L, void* object) {
   lua_remove(L, -2);
 }
 
+void luax_vthrow(lua_State* L, const char* format, va_list args) {
+  lua_pushvfstring(L, format, args);
+  lua_error(L);
+}
+
 int luax_getstack(lua_State* L) {
   const char* message = luaL_checkstring(L, -1);
   lua_getglobal(L, "debug");
diff --git a/src/luax.h b/src/luax.h
index e5356394..8a2c6f1e 100644
--- a/src/luax.h
+++ b/src/luax.h
@@ -16,6 +16,7 @@ void luax_extendtype(lua_State* L, const char* base, const char* name, const lua
 void* _luax_totype(lua_State* L, int index, const char* type);
 void* _luax_checktype(lua_State* L, int index, const char* type);
 void luax_pushobject(lua_State* L, void* object);
+void luax_vthrow(lua_State* L, const char* format, va_list args);
 int luax_getstack(lua_State* L);
 void luax_pushconf(lua_State* L);
 int luax_setconf(lua_State* L);
diff --git a/src/util.c b/src/util.c
index 10da349f..d59ea37a 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1,9 +1,6 @@
 #include "util.h"
-#include <lua.h>
-#include <lauxlib.h>
-#include <lualib.h>
-#include <stdarg.h>
 #include <stdlib.h>
+#include <stdio.h>
 #ifdef _WIN32
 #include <Windows.h>
 #else
@@ -11,15 +8,29 @@
 #include <dlfcn.h>
 #endif
 
-_Thread_local void* lovrErrorContext = NULL;
+_Thread_local lovrErrorHandler lovrErrorCallback = NULL;
+_Thread_local void* lovrErrorUserdata = NULL;
+
+void lovrSetErrorCallback(lovrErrorHandler callback, void* userdata) {
+  lovrErrorCallback = callback;
+  lovrErrorUserdata = userdata;
+}
 
 void lovrThrow(const char* format, ...) {
-  lua_State* L = (lua_State*) lovrErrorContext;
-  va_list args;
-  va_start(args, format);
-  lua_pushvfstring(L, format, args);
-  lua_error(L);
-  va_end(args);
+  if (lovrErrorCallback) {
+    va_list args;
+    va_start(args, format);
+    lovrErrorCallback(lovrErrorUserdata, format, args);
+    va_end(args);
+  } else {
+    va_list args;
+    va_start(args, format);
+    fprintf(stderr, "Error: ");
+    vfprintf(stderr, format, args);
+    fprintf(stderr, "\n");
+    va_end(args);
+    exit(EXIT_FAILURE);
+  }
 }
 
 void lovrSleep(double seconds) {
diff --git a/src/util.h b/src/util.h
index 7f8219c0..b6c0b33a 100644
--- a/src/util.h
+++ b/src/util.h
@@ -2,6 +2,7 @@
 #include "lib/tinycthread/tinycthread.h"
 #include <stdint.h>
 #include <stddef.h>
+#include <stdarg.h>
 
 #pragma once
 
@@ -20,8 +21,11 @@ typedef struct {
   float r, g, b, a;
 } Color;
 
-extern _Thread_local void* lovrErrorContext;
+typedef void (*lovrErrorHandler)(void* userdata, const char* format, va_list args);
+extern _Thread_local lovrErrorHandler lovrErrorCallback;
+extern _Thread_local void* lovrErrorUserdata;
 
+void lovrSetErrorCallback(lovrErrorHandler callback, void* context);
 void lovrThrow(const char* format, ...);
 void lovrSleep(double seconds);
 void* _lovrAlloc(const char* type, size_t size, void (*destructor)(void*));