blob: 27daf722b53466318304097a043ae9e93d1431f4 [file] [log] [blame]
// Copyright 2009 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.
//go:build darwin || dragonfly || freebsd || netbsd || openbsd
package net
import (
"runtime"
"syscall"
)
func maxListenerBacklog() int {
var (
n uint32
err error
)
switch runtime.GOOS {
case "darwin", "ios":
n, err = syscall.SysctlUint32("kern.ipc.somaxconn")
case "freebsd":
n, err = syscall.SysctlUint32("kern.ipc.soacceptqueue")
case "netbsd":
// NOTE: NetBSD has no somaxconn-like kernel state so far
case "openbsd":
n, err = syscall.SysctlUint32("kern.somaxconn")
}
if n == 0 || err != nil {
return syscall.SOMAXCONN
}
// FreeBSD stores the backlog in a uint16, as does Linux.
// Assume the other BSDs do too. Truncate number to avoid wrapping.
// See issue 5030.
if n > 1<<16-1 {
n = 1<<16 - 1
}
return int(n)
}