github.com/bir3/gocompiler@v0.9.2202/src/internal/poll/sock_cloexec.go (about) 1 // Copyright 2013 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // This file implements accept for platforms that provide a fast path for 6 // setting SetNonblock and CloseOnExec. 7 8 //go:build dragonfly || freebsd || (linux && !arm) || netbsd || openbsd || solaris 9 10 package poll 11 12 import "syscall" 13 14 // Wrapper around the accept system call that marks the returned file 15 // descriptor as nonblocking and close-on-exec. 16 func accept(s int) (int, syscall.Sockaddr, string, error) { 17 ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC) 18 // TODO: We can remove the fallback on Linux and *BSD, 19 // as currently supported versions all support accept4 20 // with SOCK_CLOEXEC, but Solaris does not. See issue #59359. 21 switch err { 22 case nil: 23 return ns, sa, "", nil 24 default: // errors other than the ones listed 25 return -1, sa, "accept4", err 26 case syscall.ENOSYS: // syscall missing 27 case syscall.EINVAL: // some Linux use this instead of ENOSYS 28 case syscall.EACCES: // some Linux use this instead of ENOSYS 29 case syscall.EFAULT: // some Linux use this instead of ENOSYS 30 } 31 32 // See ../syscall/exec_unix.go for description of ForkLock. 33 // It is probably okay to hold the lock across syscall.Accept 34 // because we have put fd.sysfd into non-blocking mode. 35 // However, a call to the File method will put it back into 36 // blocking mode. We can't take that risk, so no use of ForkLock here. 37 ns, sa, err = AcceptFunc(s) 38 if err == nil { 39 syscall.CloseOnExec(ns) 40 } 41 if err != nil { 42 return -1, nil, "accept", err 43 } 44 if err = syscall.SetNonblock(ns, true); err != nil { 45 CloseFunc(ns) 46 return -1, nil, "setnonblock", err 47 } 48 return ns, sa, "", nil 49 }