github.com/hxx258456/ccgo@v0.0.5-0.20230213014102-48b35f46f66f/internal/poll/sys_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 do not provide a fast path for
     6  // setting SetNonblock and CloseOnExec.
     7  
     8  //go:build aix || darwin || (js && wasm) || (solaris && !illumos)
     9  // +build aix darwin js,wasm solaris,!illumos
    10  
    11  package poll
    12  
    13  import (
    14  	"syscall"
    15  )
    16  
    17  // Wrapper around the accept system call that marks the returned file
    18  // descriptor as nonblocking and close-on-exec.
    19  func accept(s int) (int, syscall.Sockaddr, string, error) {
    20  	// See ../syscall/exec_unix.go for description of ForkLock.
    21  	// It is probably okay to hold the lock across syscall.Accept
    22  	// because we have put fd.sysfd into non-blocking mode.
    23  	// However, a call to the File method will put it back into
    24  	// blocking mode. We can't take that risk, so no use of ForkLock here.
    25  	ns, sa, err := AcceptFunc(s)
    26  	if err == nil {
    27  		syscall.CloseOnExec(ns)
    28  	}
    29  	if err != nil {
    30  		return -1, nil, "accept", err
    31  	}
    32  	if err = syscall.SetNonblock(ns, true); err != nil {
    33  		CloseFunc(ns)
    34  		return -1, nil, "setnonblock", err
    35  	}
    36  	return ns, sa, "", nil
    37  }