// descriptor as nonblocking and close-on-exec.
func accept(s int) (int, syscall.Sockaddr, string, error) {
ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC)
- // On Linux the accept4 system call was introduced in 2.6.28
- // kernel and on FreeBSD it was introduced in 10 kernel. If we
- // get an ENOSYS error on both Linux and FreeBSD, or EINVAL
- // error on Linux, fall back to using accept.
- switch err {
- case nil:
- return ns, sa, "", nil
- default: // errors other than the ones listed
- return -1, sa, "accept4", err
- case syscall.ENOSYS: // syscall missing
- case syscall.EINVAL: // some Linux use this instead of ENOSYS
- case syscall.EACCES: // some Linux use this instead of ENOSYS
- case syscall.EFAULT: // some Linux use this instead of ENOSYS
- }
-
- // See ../syscall/exec_unix.go for description of ForkLock.
- // It is probably okay to hold the lock across syscall.Accept
- // because we have put fd.sysfd into non-blocking mode.
- // However, a call to the File method will put it back into
- // blocking mode. We can't take that risk, so no use of ForkLock here.
- ns, sa, err = AcceptFunc(s)
- if err == nil {
- syscall.CloseOnExec(ns)
- }
if err != nil {
- return -1, nil, "accept", err
- }
- if err = syscall.SetNonblock(ns, true); err != nil {
- CloseFunc(ns)
- return -1, nil, "setnonblock", err
+ return -1, sa, "accept4", err
}
return ns, sa, "", nil
}