forked from mirror/redis
51 lines
940 B
Go
51 lines
940 B
Go
//go:build linux || darwin || dragonfly || freebsd || netbsd || openbsd || solaris || illumos
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// +build linux darwin dragonfly freebsd netbsd openbsd solaris illumos
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package pool
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import (
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"errors"
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"io"
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"net"
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"syscall"
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"time"
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)
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var errUnexpectedRead = errors.New("unexpected read from socket")
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func connCheck(conn net.Conn) error {
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// Reset previous timeout.
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_ = conn.SetDeadline(time.Time{})
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sysConn, ok := conn.(syscall.Conn)
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if !ok {
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return nil
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}
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rawConn, err := sysConn.SyscallConn()
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if err != nil {
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return err
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}
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var sysErr error
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err = rawConn.Read(func(fd uintptr) bool {
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var buf [1]byte
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n, err := syscall.Read(int(fd), buf[:])
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switch {
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case n == 0 && err == nil:
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sysErr = io.EOF
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case n > 0:
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sysErr = errUnexpectedRead
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case err == syscall.EAGAIN || err == syscall.EWOULDBLOCK:
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sysErr = nil
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default:
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sysErr = err
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}
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return true
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})
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if err != nil {
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return err
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}
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return sysErr
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}
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