整理

2026-03-23 20:54:41 +08:00
commit e13b3650e9
4596 changed files with 1015768 additions and 0 deletions
--- a/include/boost/scope/fd_deleter.hpp
+++ b/include/boost/scope/fd_deleter.hpp
@@ -0,0 +1,82 @@
+/*
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * https://www.boost.org/LICENSE_1_0.txt)
+ *
+ * Copyright (c) 2023 Andrey Semashev
+ */
+/*!
+ * \file scope/fd_deleter.hpp
+ *
+ * This header contains definition of a deleter function object for
+ * POSIX-like file descriptors for use with \c unique_resource.
+ */
+
+#ifndef BOOST_SCOPE_FD_DELETER_HPP_INCLUDED_
+#define BOOST_SCOPE_FD_DELETER_HPP_INCLUDED_
+
+#include <boost/scope/detail/config.hpp>
+
+#if !defined(BOOST_WINDOWS)
+#include <unistd.h>
+#if defined(hpux) || defined(_hpux) || defined(__hpux)
+#include <cerrno>
+#endif
+#else // !defined(BOOST_WINDOWS)
+#include <io.h>
+#endif // !defined(BOOST_WINDOWS)
+
+#include <boost/scope/detail/header.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+namespace boost {
+namespace scope {
+
+//! POSIX-like file descriptor deleter
+struct fd_deleter
+{
+    using result_type = void;
+
+    //! Closes the file descriptor
+    result_type operator() (int fd) const noexcept
+    {
+#if !defined(BOOST_WINDOWS)
+#if defined(hpux) || defined(_hpux) || defined(__hpux)
+        // Some systems don't close the file descriptor in case if the thread is interrupted by a signal and close(2) returns EINTR.
+        // Other (most) systems do close the file descriptor even when when close(2) returns EINTR, and attempting to close it
+        // again could close a different file descriptor that was opened by a different thread.
+        //
+        // Future POSIX standards will likely fix this by introducing posix_close (see https://www.austingroupbugs.net/view.php?id=529)
+        // and prohibiting returning EINTR from close(2), but we still have to support older systems where this new behavior is not available and close(2)
+        // behaves differently between systems.
+        int res;
+        while (true)
+        {
+            res = ::close(fd);
+            if (BOOST_UNLIKELY(res < 0))
+            {
+                int err = errno;
+                if (err == EINTR)
+                    continue;
+            }
+
+            break;
+        }
+#else
+        ::close(fd);
+#endif
+#else // !defined(BOOST_WINDOWS)
+        ::_close(fd);
+#endif // !defined(BOOST_WINDOWS)
+    }
+};
+
+} // namespace scope
+} // namespace boost
+
+#include <boost/scope/detail/footer.hpp>
+
+#endif // BOOST_SCOPE_FD_DELETER_HPP_INCLUDED_