/
sock_linux.go
62 lines (51 loc) · 1.3 KB
/
sock_linux.go
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// Copyright (c) 2017 Ma Weiwei, Max Riveiro
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package socket
import (
"bufio"
"os"
"strconv"
"strings"
"golang.org/x/sys/unix"
)
const (
maxUint16Value = 1<<16 - 1
)
func maxListenerBacklog() int {
fd, err := os.Open("/proc/sys/net/core/somaxconn")
if err != nil {
return unix.SOMAXCONN
}
defer fd.Close()
rd := bufio.NewReader(fd)
line, err := rd.ReadString('\n')
if err != nil {
return unix.SOMAXCONN
}
f := strings.Fields(line)
if len(f) < 1 {
return unix.SOMAXCONN
}
value, err := strconv.Atoi(f[0])
if err != nil || value == 0 {
return unix.SOMAXCONN
}
// Linux stores the backlog in a uint16.
// Truncate number to avoid wrapping.
// See issue 5030.
if value > maxUint16Value {
value = maxUint16Value
}
return value
}