libbinder: simpler scope_guard implementation
libbinder_on_trusty_mock size: 289,374 -> 286,533 bytes
Bug: 338458975
Test: TH
Change-Id: I9fc817ba09c8697fb8b5f566cec28f15b6e7ea5d
diff --git a/libs/binder/include/binder/Functional.h b/libs/binder/include/binder/Functional.h
index 08e3b21..bb0e5f4 100644
--- a/libs/binder/include/binder/Functional.h
+++ b/libs/binder/include/binder/Functional.h
@@ -17,11 +17,38 @@
#pragma once
#include <functional>
-#include <memory>
+#include <optional>
namespace android::binder::impl {
template <typename F>
+class scope_guard;
+
+template <typename F>
+scope_guard<F> make_scope_guard(F f);
+
+template <typename F>
+class scope_guard {
+public:
+ inline ~scope_guard() {
+ if (f_.has_value()) std::move(f_.value())();
+ }
+ inline void release() { f_.reset(); }
+
+private:
+ friend scope_guard<F> android::binder::impl::make_scope_guard(F);
+
+ inline scope_guard(F&& f) : f_(std::move(f)) {}
+
+ std::optional<F> f_;
+};
+
+template <typename F>
+inline scope_guard<F> make_scope_guard(F f) {
+ return scope_guard<F>(std::move(f));
+}
+
+template <typename F>
constexpr void assert_small_callable() {
// While this buffer (std::function::__func::__buf_) is an implementation detail generally not
// accessible to users, it's a good bet to assume its size to be around 3 pointers.
@@ -32,12 +59,6 @@
"Try using std::ref, but make sure lambda lives long enough to be called.");
}
-template <typename F>
-std::unique_ptr<void, std::function<void(void*)>> make_scope_guard(F&& f) {
- assert_small_callable<decltype(std::bind(f))>();
- return {reinterpret_cast<void*>(true), std::bind(f)};
-}
-
template <typename T>
class SmallFunction : public std::function<T> {
public: