1 files changed, 50 insertions, 0 deletions
diff --git a/src/net/sock_cloexec.go b/src/net/sock_cloexec.go
new file mode 100644
index 0000000..5f345f0
--- /dev/null
+++ b/src/net/sock_cloexec.go
@@ -0,0 +1,50 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements sysSocket and accept for platforms that
+// provide a fast path for setting SetNonblock and CloseOnExec.
+
+// +build dragonfly freebsd illumos linux netbsd openbsd
+
+package net
+
+import (
+	"internal/poll"
+	"os"
+	"syscall"
+)
+
+// Wrapper around the socket system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func sysSocket(family, sotype, proto int) (int, error) {
+	s, err := socketFunc(family, sotype|syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC, proto)
+	// On Linux the SOCK_NONBLOCK and SOCK_CLOEXEC flags were
+	// introduced in 2.6.27 kernel and on FreeBSD both flags were
+	// introduced in 10 kernel. If we get an EINVAL error on Linux
+	// or EPROTONOSUPPORT error on FreeBSD, fall back to using
+	// socket without them.
+	switch err {
+	case nil:
+		return s, nil
+	default:
+		return -1, os.NewSyscallError("socket", err)
+	case syscall.EPROTONOSUPPORT, syscall.EINVAL:
+	}
+
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	syscall.ForkLock.RLock()
+	s, err = socketFunc(family, sotype, proto)
+	if err == nil {
+		syscall.CloseOnExec(s)
+	}
+	syscall.ForkLock.RUnlock()
+	if err != nil {
+		return -1, os.NewSyscallError("socket", err)
+	}
+	if err = syscall.SetNonblock(s, true); err != nil {
+		poll.CloseFunc(s)
+		return -1, os.NewSyscallError("setnonblock", err)
+	}
+	return s, nil
+}