lib-lua: Fix script loading

Handle error cases correctly.

diff --git a/src/lib-lua/dlua-script.c b/src/lib-lua/dlua-script.c
index fe41fba7beeac5a2c429c051b39f9b79cb94753f..8ed31a7010a12db541364458302fdd4c5b611c4d 100644 (file)
--- a/src/lib-lua/dlua-script.c
+++ b/src/lib-lua/dlua-script.c
@@ -210,7 +210,7 @@ int dlua_script_init(struct dlua_script *script, const char **error_r)
        if (dlua_pcall(script->L, LUA_SCRIPT_INIT_FN, 0, 1, error_r) < 0)
                return -1;
 
-       if (lua_isinteger(script->L, -1)) {
+       if (lua_isinteger(script->L, -1) == 1) {
                ret = lua_tointeger(script->L, -1);
                if (ret != 0)
                        *error_r = "Script init failed";
@@ -257,15 +257,30 @@ static struct dlua_script *dlua_create_script(const char *name,
 
 static int dlua_run_script(struct dlua_script *script, const char **error_r)
 {
-       int err = lua_pcall(script->L, 0, 0, 0);
-       if (err != 0) {
+       /* put the error handler before script being called */
+       lua_getglobal(script->L, "debug");
+       lua_getfield(script->L, -1, "traceback");
+       lua_replace(script->L, -2);
+       lua_insert(script->L, -2);
+
+       /* we don't want anything to be returned here */
+       /* stack before lua_pcall
+               debug.traceback
+               loaded script as function
+       */
+       int err = lua_pcall(script->L, 0, 0, 1);
+       if (err != LUA_OK) {
                *error_r = t_strdup_printf("lua_pcall(%s) failed: %s",
                                           script->filename,
                                           lua_tostring(script->L, -1));
-               lua_pop(script->L,1);
-               return -1;
+               /* pop error and debug handler */
+               lua_pop(script->L, 2);
+               err = -1;
+       } else {
+               /* pop debug handler */
+               lua_pop(script->L, 1);
        }
-       return 0;
+       return err;
 }
 
 static int
@@ -287,6 +302,7 @@ dlua_script_create_finish(struct dlua_script *script, struct dlua_script **scrip
 
        *script_r = script;
 
+       i_assert(lua_gettop(script->L) == 0);
        return 0;
 }
 
@@ -303,14 +319,18 @@ int dlua_script_create_string(const char *str, struct dlua_script **script_r,
        fn = binary_to_hex(scripthash, sizeof(scripthash));
 
        script = dlua_create_script(fn, event_parent);
-       if ((err = luaL_loadstring(script->L, str)) != 0) {
+       err = luaL_loadstring(script->L, str);
+       switch (err) {
+       case LUA_OK:
+               return dlua_script_create_finish(script, script_r, error_r);
+       default:
                *error_r = t_strdup_printf("lua_load(<string>) failed: %s",
-                                          dlua_errstr(err));
-               dlua_script_unref(&script);
-               return -1;
+                                          lua_tostring(script->L, -1));
+               lua_pop(script->L, 1);
+               break;
        }
-
-       return dlua_script_create_finish(script, script_r, error_r);
+       dlua_script_unref(&script);
+       return -1;
 }
 
 int dlua_script_create_file(const char *file, struct dlua_script **script_r,
@@ -330,7 +350,7 @@ int dlua_script_create_file(const char *file, struct dlua_script **script_r,
        }
 
        script = dlua_create_script(file, event_parent);
-       if ((err = luaL_loadfile(script->L, file)) != 0) {
+       if ((err = luaL_loadfile(script->L, file)) != LUA_OK) {
                *error_r = t_strdup_printf("lua_load(%s) failed: %s",
                                           file, dlua_errstr(err));
                dlua_script_unref(&script);
@@ -352,7 +372,7 @@ int dlua_script_create_stream(struct istream *is, struct dlua_script **script_r,
        script = dlua_create_script(filename, event_parent);
        script->in = is;
        script->filename = p_strdup(script->pool, filename);
-       if ((err = lua_load(script->L, dlua_reader, script, filename, 0)) < 0) {
+       if ((err = lua_load(script->L, dlua_reader, script, filename, 0)) != LUA_OK) {
                *error_r = t_strdup_printf("lua_load(%s) failed: %s",
                                           filename, dlua_errstr(err));
                dlua_script_unref(&script);