HALF WORK: refactor something and implement part of subprocess.

1 files changed, 26 insertions, 0 deletions

diff --git a/include/cru/common/Guard.h b/include/cru/common/Guard.h
new file mode 100644
index 00000000..5a9f9c5d
--- /dev/null
+++ b/include/cru/common/Guard.h
@@ -0,0 +1,26 @@
+#pragma once
+
+#include <functional>
+
+namespace cru {
+struct Guard {
+  using ExitFunc = std::function<void()>;
+
+  Guard() = default;
+  explicit Guard(const ExitFunc& f) : on_exit(f) {}
+  explicit Guard(ExitFunc&& f) : on_exit(std::move(f)) {}
+  Guard(const Guard&) = delete;
+  Guard(Guard&&) = default;
+  Guard& operator=(const Guard&) = delete;
+  Guard& operator=(Guard&&) = default;
+  ~Guard() {
+    if (on_exit) {
+      on_exit();
+    }
+  }
+
+  void Drop() { on_exit = {}; }
+
+  ExitFunc on_exit;
+};
+}  // namespace cru