add Handle class

It's derived from various projects of mine.

2 files changed, 81 insertions, 0 deletions

diff --git a/include/winapi/handle.hpp b/include/winapi/handle.hpp
new file mode 100644
index 0000000..9e9661b
--- /dev/null
+++ b/include/winapi/handle.hpp
@@ -0,0 +1,73 @@
+// Copyright (c) 2020 Egor Tensin <Egor.Tensin@gmail.com>
+// This file is part of the "winapi-common" project.
+// For details, see https://github.com/egor-tensin/winapi-common.
+// Distributed under the MIT License.
+
+#pragma once
+
+#include "workarounds.hpp"
+
+#include <boost/config.hpp>
+
+#include <windows.h>
+
+#include <cassert>
+#include <memory>
+#include <utility>
+
+namespace winapi {
+
+class Handle {
+public:
+    Handle() = default;
+
+    explicit Handle(HANDLE raw)
+        : impl{raw}
+    { }
+
+    Handle(Handle&& other) BOOST_NOEXCEPT_OR_NOTHROW {
+        swap(other);
+    }
+
+    Handle& operator=(Handle other) BOOST_NOEXCEPT_OR_NOTHROW { 
+        swap(other);
+        return *this;
+    }
+
+    void swap(Handle& other) BOOST_NOEXCEPT_OR_NOTHROW {
+        using std::swap;
+        swap(impl, other.impl);
+    }
+
+    explicit operator HANDLE() const { return impl.get(); }
+
+private:
+    struct Close {
+        void operator()(HANDLE raw) const {
+            if (raw == NULL || raw == INVALID_HANDLE_VALUE)
+                return;
+            const auto ret = ::CloseHandle(raw);
+            assert(ret);
+            WINAPI_UNUSED_PARAMETER(ret);
+        }
+    };
+
+    std::unique_ptr<void, Close> impl;
+
+    Handle(const Handle&) = delete;
+};
+
+inline void swap(Handle& a, Handle& b) BOOST_NOEXCEPT_OR_NOTHROW {
+    a.swap(b);
+}
+
+}
+
+namespace std {
+
+template <>
+inline void swap(winapi::Handle& a, winapi::Handle& b) BOOST_NOEXCEPT_OR_NOTHROW {
+    a.swap(b);
+}
+
+} // namespace std
diff --git a/include/winapi/workarounds.hpp b/include/winapi/workarounds.hpp
new file mode 100644
index 0000000..a5a3607
--- /dev/null
+++ b/include/winapi/workarounds.hpp
@@ -0,0 +1,8 @@
+// Copyright (c) 2020 Egor Tensin <Egor.Tensin@gmail.com>
+// This file is part of the "winapi-common" project.
+// For details, see https://github.com/egor-tensin/winapi-common.
+// Distributed under the MIT License.
+
+#pragma once
+
+#define WINAPI_UNUSED_PARAMETER(...) (void)(__VA_ARGS__)