mail-lua: Properly refcount user object

Prevents user object from going away unexpectedly, and makes
sure it gets released correctly.

diff --git a/src/plugins/mail-lua/mail-storage-lua.c b/src/plugins/mail-lua/mail-storage-lua.c
index 7d8a25c0834f77d538bfb2767bc4a7a075433c22..45f92d0ced00df5915407ce44e6cd8240803db1e 100644 (file)
--- a/src/plugins/mail-lua/mail-storage-lua.c
+++ b/src/plugins/mail-lua/mail-storage-lua.c
@@ -18,6 +18,8 @@
 /** MAIL USER
  */
 
+static int lua_storage_mail_user_unref(lua_State *L);
+
 void dlua_push_mail_user(struct dlua_script *script, struct mail_user *user)
 {
        luaL_checkstack(script->L, 20, "out of memory");
@@ -25,7 +27,13 @@ void dlua_push_mail_user(struct dlua_script *script, struct mail_user *user)
        lua_createtable(script->L, 0, 20);
        luaL_setmetatable(script->L, LUA_STORAGE_MAIL_USER);
 
-       lua_pushlightuserdata(script->L, user);
+       mail_user_ref(user);
+       struct mail_user **ptr = lua_newuserdata(script->L, sizeof(struct mail_user*));
+       *ptr = user;
+       lua_createtable(script->L, 0, 1);
+       lua_pushcfunction(script->L, lua_storage_mail_user_unref);
+       lua_setfield(script->L, -2, "__gc");
+       lua_setmetatable(script->L, -2);
        lua_setfield(script->L, -2, "item");
 
 #undef LUA_TABLE_SETNUMBER
@@ -74,9 +82,9 @@ lua_check_storage_mail_user(struct dlua_script *script, int arg)
        }
        lua_pushliteral(script->L, "item");
        lua_rawget(script->L, arg);
-       void *bp = (void*)lua_touserdata(script->L, -1);
+       struct mail_user **bp = lua_touserdata(script->L, -1);
        lua_pop(script->L, 1);
-       return (struct mail_user*)bp;
+       return *bp;
 }
 
 static int lua_storage_mail_user_tostring(lua_State *L)
@@ -176,13 +184,10 @@ static int lua_storage_mail_user_mailbox_alloc(lua_State *L)
 static int lua_storage_mail_user_unref(lua_State *L)
 {
        struct dlua_script *script = dlua_script_from_state(L);
-       (void)lua_check_storage_mail_user(script, 1);
-
-       /* reset value to NULL */
-       lua_pushliteral(script->L, "item");
-       lua_pushnil(script->L);
-       lua_rawset(script->L, 1);
-
+       struct mail_user **ptr = lua_touserdata(script->L, 1);
+       if (*ptr != NULL)
+               mail_user_unref(ptr);
+       *ptr = NULL;
        return 0;
 }
 
@@ -191,7 +196,6 @@ static luaL_Reg lua_storage_mail_user_methods[] = {
        { "__eq", lua_storage_mail_user_eq },
        { "__lt", lua_storage_mail_user_lt },
        { "__le", lua_storage_mail_user_le },
-       { "__gc", lua_storage_mail_user_unref },
        { "plugin_getenv", lua_storage_mail_user_plugin_getenv },
        { "var_expand", lua_storage_mail_user_var_expand },
        { "mailbox", lua_storage_mail_user_mailbox_alloc },