add honey_lua_pcall with traceback ability

1 files changed, 40 insertions, 0 deletions

diff --git a/src/honey_lua.c b/src/honey_lua.c
index f397872..ded2a91 100644
--- a/src/honey_lua.c
+++ b/src/honey_lua.c
@@ -190,3 +190,43 @@ void honey_lua_push_element(lua_State* L, honey_lua_element element)
         break;
     }
 }
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+int honey_lua_traceback(lua_State* L)
+{
+    if (!lua_isstring(L, 1))
+        /* 'message' is not a string, keep intact. */
+        return 1;
+
+    lua_getglobal(L, "debug");
+    if (!lua_istable(L, -1)) {
+        lua_pop(L, 1);
+        return 1;
+    }
+
+    lua_getfield(L, -1, "traceback");
+    if (!lua_isfunction(L, -1)) {
+        lua_pop(L, 2);
+        return 1;
+    }
+
+    lua_pushvalue(L, 1);
+    lua_pushinteger(L, 2);
+    lua_call(L, 2, 1);
+    return 1;
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+int honey_lua_pcall(lua_State* L, int nargs, int nret)
+{
+    int traceback_pos = lua_gettop(L) - nargs;
+    lua_pushcfunction(L, honey_lua_traceback);
+    lua_insert(L, traceback_pos);
+
+    int result = lua_pcall(L, nargs, nret, traceback_pos);
+    lua_remove(L, traceback_pos);
+    return result;
+}
+