1 files changed, 64 insertions, 20 deletions

diff --git a/src/script/common/c_internal.cpp b/src/script/common/c_internal.cpp
index f811dd5d3..2a10ce0f2 100644
--- a/src/script/common/c_internal.cpp
+++ b/src/script/common/c_internal.cpp
@@ -20,7 +20,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "common/c_internal.h"
 #include "debug.h"
 #include "log.h"
-#include "main.h"
 #include "settings.h"
 
 std::string script_get_backtrace(lua_State *L)
@@ -64,19 +63,65 @@ int script_exception_wrapper(lua_State *L, lua_CFunction f)
 		return f(L);  // Call wrapped function and return result.
 	} catch (const char *s) {  // Catch and convert exceptions.
 		lua_pushstring(L, s);
-	} catch (std::exception& e) {
+	} catch (std::exception &e) {
 		lua_pushstring(L, e.what());
-	} catch (...) {
-		lua_pushliteral(L, "caught (...)");
 	}
 	return lua_error(L);  // Rethrow as a Lua error.
 }
 
-void script_error(lua_State *L)
+/*
+ * Note that we can't get tracebacks for LUA_ERRMEM or LUA_ERRERR (without
+ * hacking Lua internals).  For LUA_ERRMEM, this is because memory errors will
+ * not execute the the error handler, and by the time lua_pcall returns the
+ * execution stack will have already been unwound.  For LUA_ERRERR, there was
+ * another error while trying to generate a backtrace from a LUA_ERRRUN.  It is
+ * presumed there is an error with the internal Lua state and thus not possible
+ * to gather a coherent backtrace.  Realistically, the best we can do here is
+ * print which C function performed the failing pcall.
+ */
+void script_error(lua_State *L, int pcall_result, const char *mod, const char *fxn)
 {
-	const char *s = lua_tostring(L, -1);
-	std::string str(s ? s : "");
-	throw LuaError(str);
+	if (pcall_result == 0)
+		return;
+
+	const char *err_type;
+	switch (pcall_result) {
+	case LUA_ERRRUN:
+		err_type = "Runtime";
+		break;
+	case LUA_ERRMEM:
+		err_type = "OOM";
+		break;
+	case LUA_ERRERR:
+		err_type = "Double fault";
+		break;
+	default:
+		err_type = "Unknown";
+	}
+
+	if (!mod)
+		mod = "??";
+
+	if (!fxn)
+		fxn = "??";
+
+	const char *err_descr = lua_tostring(L, -1);
+	if (!err_descr)
+		err_descr = "<no description>";
+
+	char buf[256];
+	snprintf(buf, sizeof(buf), "%s error from mod '%s' in callback %s(): ",
+		err_type, mod, fxn);
+
+	std::string err_msg(buf);
+	err_msg += err_descr;
+
+	if (pcall_result == LUA_ERRMEM) {
+		err_msg += "\nCurrent Lua memory usage: "
+			+ itos(lua_gc(L, LUA_GCCOUNT, 0) >> 10) + " MB";
+	}
+
+	throw LuaError(err_msg);
 }
 
 // Push the list of callbacks (a lua table).
@@ -85,9 +130,10 @@ void script_error(lua_State *L)
 // - runs the callbacks
 // - replaces the table and arguments with the return value,
 //     computed depending on mode
-void script_run_callbacks(lua_State *L, int nargs, RunCallbacksMode mode)
+void script_run_callbacks_f(lua_State *L, int nargs,
+	RunCallbacksMode mode, const char *fxn)
 {
-	assert(lua_gettop(L) >= nargs + 1);
+	FATAL_ERROR_IF(lua_gettop(L) < nargs + 1, "Not enough arguments");
 
 	// Insert error handler
 	lua_pushcfunction(L, script_error_handler);
@@ -107,14 +153,14 @@ void script_run_callbacks(lua_State *L, int nargs, RunCallbacksMode mode)
 	// Stack now looks like this:
 	// ... <error handler> <run_callbacks> <table> <mode> <arg#1> <arg#2> ... <arg#n>
 
-	if (lua_pcall(L, nargs + 2, 1, errorhandler)) {
-		script_error(L);
-	}
+	int result = lua_pcall(L, nargs + 2, 1, errorhandler);
+	if (result != 0)
+		script_error(L, result, NULL, fxn);
 
 	lua_remove(L, -2); // Remove error handler
 }
 
-void log_deprecated(lua_State *L, std::string message)
+void log_deprecated(lua_State *L, const std::string &message)
 {
 	static bool configured = false;
 	static bool dolog      = false;
@@ -125,8 +171,7 @@ void log_deprecated(lua_State *L, std::string message)
 		std::string value = g_settings->get("deprecated_lua_api_handling");
 		if (value == "log") {
 			dolog = true;
-		}
-		if (value == "error") {
+		} else if (value == "error") {
 			dolog = true;
 			doerror = true;
 		}
@@ -134,11 +179,10 @@ void log_deprecated(lua_State *L, std::string message)
 
 	if (doerror) {
 		if (L != NULL) {
-			script_error(L);
+			script_error(L, LUA_ERRRUN, NULL, NULL);
 		} else {
-			/* As of april 2014 assert is not optimized to nop in release builds
-			 * therefore this is correct. */
-			assert("Can't do a scripterror for this deprecated message, so exit completely!");
+			FATAL_ERROR("Can't do a scripterror for this deprecated message, "
+				"so exit completely!");
 		}
 	}