use err defers

1 files changed, 19 insertions, 1 deletions

diff --git a/src/utils.h b/src/utils.h
index deba95f..ce19428 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -88,4 +88,22 @@ struct defer_s {
   ~defer_s() { func(); }
 };
 
-#define wayc_defer(func) auto WAYC_UNIQUE(_defer_) = defer_s([&]() { func; })
\ No newline at end of file
+#define wayc_defer(func) auto WAYC_UNIQUE(_defer_) = defer_s([&]() { func; })
+
+template <typename Func, typename S>
+struct defer_cond_s {
+  Func func;
+  S* signal;
+  S expected;
+
+  defer_cond_s(Func func, S* cond, S expected)
+      : func(func), signal(cond), expected(expected) {}
+
+  ~defer_cond_s() {
+    if (*signal == expected) return;
+    func();
+  }
+};
+
+#define wayc_defer_cond(func, cond, expected) \
+  auto WAYC_UNIQUE(_defer_) = defer_cond_s([&]() { func; }, &cond, expected)
\ No newline at end of file