From 2e2d1bd3b6c7776b77c33b94f30ead89367a71e6 Mon Sep 17 00:00:00 2001 From: Lexi Winter Date: Tue, 1 Jul 2025 17:07:04 +0100 Subject: add nihil.std --- nihil.util/save_errno.ccm | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 nihil.util/save_errno.ccm (limited to 'nihil.util/save_errno.ccm') diff --git a/nihil.util/save_errno.ccm b/nihil.util/save_errno.ccm new file mode 100644 index 0000000..27567f8 --- /dev/null +++ b/nihil.util/save_errno.ccm @@ -0,0 +1,35 @@ +// This source code is released into the public domain. +module; + +#include + +export module nihil.util:save_errno; + +// save_errno: save the current value of errno and restore it when we're destroyed. +// this allows wrappers around C functions that use errno to preserve the caller's +// errno value. + +namespace nihil { + +export struct save_errno final +{ + save_errno() : m_errno(errno) {} + + ~save_errno() + { + errno = m_errno; + } + + // Not copyable + save_errno(const save_errno&) = delete; + auto operator=(const save_errno&) -> save_errno & = delete; + + // Not movable + save_errno(save_errno&&) = delete; + auto operator=(save_errno&&) -> save_errno & = delete; + +private: + int m_errno; +}; + +} // namespace nihil -- cgit v1.2.3