wplua: use the error handler also when loading chunks

... and improve its output

lib/wplua/closure.c

@@ -7,6 +7,7 @@
  */
 
 #include "wplua.h"
+#include "private.h"
 #include <wp/wp.h>
 
 typedef struct _WpLuaClosure WpLuaClosure;
@@ -16,47 +17,6 @@ struct _WpLuaClosure
   int func_ref;
 };
 
-static int
-_wplua_closure_errhandler (lua_State *L)
-{
-  wp_warning ("%s", lua_tostring (L, -1));
-  lua_pop (L, 1);
-
-  luaL_traceback (L, L, "traceback:\n", 1);
-  wp_warning ("%s", lua_tostring (L, -1));
-  lua_pop (L, 1);
-
-  return 0;
-}
-
-static int
-_wplua_closure_pcall (lua_State *L, int nargs, int nret)
-{
-  int hpos = lua_gettop (L) - nargs;
-  int ret = LUA_OK;
-
-  lua_pushcfunction (L, _wplua_closure_errhandler);
-  lua_insert (L, hpos);
-
-  ret = lua_pcall (L, nargs, nret, hpos);
-  switch (ret) {
-  case LUA_ERRMEM:
-    wp_critical ("not enough memory");
-    break;
-  case LUA_ERRERR:
-    wp_critical ("error running the message handler");
-    break;
-  case LUA_ERRGCMM:
-    wp_critical ("error running __gc");
-    break;
-  default:
-    break;
-  }
-
-  lua_remove (L, hpos);
-  return ret;
-}
-
 static void
 _wplua_closure_marshal (GClosure *closure, GValue *return_value,
     guint n_param_values, const GValue *param_values,
@@ -81,7 +41,7 @@ _wplua_closure_marshal (GClosure *closure, GValue *return_value,
     wplua_gvalue_to_lua (L, &param_values[i]);
 
   /* call in protected mode */
-  int res = _wplua_closure_pcall (L, n_param_values, return_value ? 1 : 0);
+  int res = _wplua_pcall (L, n_param_values, return_value ? 1 : 0);
 
   /* handle the result */
   if (res == LUA_OK && return_value && lua_gettop (L) >= 1)

lib/wplua/private.h

@@ -29,6 +29,9 @@ gboolean _wplua_isgvalue_userdata (lua_State *L, int idx, GType type);
 int _wplua_gvalue_userdata___gc (lua_State *L);
 int _wplua_gvalue_userdata___eq (lua_State *L);
 
+/* wplua.c */
+int _wplua_pcall (lua_State *L, int nargs, int nret);
+
 G_END_DECLS
 
 #endif

lib/wplua/wplua.c

@@ -42,6 +42,43 @@ _wplua_openlibs (lua_State *L)
   }
 }
 
+static int
+_wplua_errhandler (lua_State *L)
+{
+  luaL_traceback (L, L, NULL, 1);
+  wp_warning ("%s\n%s", lua_tostring (L, -2), lua_tostring (L, -1));
+  lua_pop (L, 2);
+  return 0;
+}
+
+int
+_wplua_pcall (lua_State *L, int nargs, int nret)
+{
+  int hpos = lua_gettop (L) - nargs;
+  int ret = LUA_OK;
+
+  lua_pushcfunction (L, _wplua_errhandler);
+  lua_insert (L, hpos);
+
+  ret = lua_pcall (L, nargs, nret, hpos);
+  switch (ret) {
+  case LUA_ERRMEM:
+    wp_critical ("not enough memory");
+    break;
+  case LUA_ERRERR:
+    wp_critical ("error running the message handler");
+    break;
+  case LUA_ERRGCMM:
+    wp_critical ("error running __gc");
+    break;
+  default:
+    break;
+  }
+
+  lua_remove (L, hpos);
+  return ret;
+}
+
 lua_State *
 wplua_new (void)
 {
@@ -152,11 +189,10 @@ _wplua_load_buffer (lua_State * L, const gchar *buf, gsize size,
     return FALSE;
   }
 
-  ret = lua_pcall (L, sandbox, 0, 0);
+  ret = _wplua_pcall (L, sandbox, 0);
   if (ret != LUA_OK) {
     g_set_error (error, WP_DOMAIN_LUA, WP_LUA_ERROR_RUNTIME,
-        "Failed to run: %s", lua_tostring (L, -1));
-    lua_pop (L, 1);
+        "Runtime error while loading '%s'", name);
     return FALSE;
   }