| // Copyright 2024 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 accept for platforms that provide a fast path for |
| // setting SetNonblock and CloseOnExec, but don't necessarily have accept4. |
| // The accept4(3c) function was added to Oracle Solaris in the Solaris 11.4.0 |
| // release. Thus, on releases prior to 11.4, we fall back to the combination |
| // of accept(3c) and fcntl(2). |
| |
| package poll |
| |
| import ( |
| "internal/syscall/unix" |
| "syscall" |
| ) |
| |
| // Wrapper around the accept system call that marks the returned file |
| // descriptor as nonblocking and close-on-exec. |
| func accept(s int) (int, syscall.Sockaddr, string, error) { |
| // Perform a cheap test and try the fast path first. |
| if unix.SupportAccept4() { |
| ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC) |
| if err != nil { |
| return -1, nil, "accept4", err |
| } |
| return ns, sa, "", nil |
| } |
| |
| // 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 ns, sa, "", nil |
| } |