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https://github.com/golang/go
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18441e8ade
It might be non-blocking, but it also might be blocking. Cannot take the chance, as Accept might block indefinitely and make it impossible to acquire ForkLock exclusively (during fork+exec). Fixes #4737. R=golang-dev, dave, iant, mikioh.mikioh CC=golang-dev https://golang.org/cl/7309050
55 lines
1.6 KiB
Go
55 lines
1.6 KiB
Go
// Copyright 2013 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// This file implements sysSocket and accept for platforms that do not
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// provide a fast path for setting SetNonblock and CloseOnExec.
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// +build darwin freebsd netbsd openbsd
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package net
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import "syscall"
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// Wrapper around the socket system call that marks the returned file
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// descriptor as nonblocking and close-on-exec.
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func sysSocket(f, t, p int) (int, error) {
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// See ../syscall/exec_unix.go for description of ForkLock.
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syscall.ForkLock.RLock()
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s, err := syscall.Socket(f, t, p)
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if err == nil {
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syscall.CloseOnExec(s)
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}
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syscall.ForkLock.RUnlock()
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if err != nil {
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return -1, err
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}
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if err = syscall.SetNonblock(s, true); err != nil {
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syscall.Close(s)
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return -1, err
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}
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return s, nil
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}
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// Wrapper around the accept system call that marks the returned file
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// descriptor as nonblocking and close-on-exec.
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func accept(fd int) (int, syscall.Sockaddr, error) {
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// See ../syscall/exec_unix.go for description of ForkLock.
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// It is probably okay to hold the lock across syscall.Accept
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// because we have put fd.sysfd into non-blocking mode.
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// However, a call to the File method will put it back into
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// blocking mode. We can't take that risk, so no use of ForkLock here.
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nfd, sa, err := syscall.Accept(fd)
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if err == nil {
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syscall.CloseOnExec(nfd)
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}
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if err != nil {
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return -1, nil, err
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}
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if err = syscall.SetNonblock(nfd, true); err != nil {
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syscall.Close(nfd)
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return -1, nil, err
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}
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return nfd, sa, nil
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}
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