07363a45fe
golang native memif driver Type: feature Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com> Change-Id: I693156a44011c80025245d25134f5bf5db6eba82 Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
61 lines
1.5 KiB
Go
61 lines
1.5 KiB
Go
/*
|
|
*------------------------------------------------------------------
|
|
* Copyright (c) 2020 Cisco and/or its affiliates.
|
|
* 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 memif
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"syscall"
|
|
"unsafe"
|
|
)
|
|
|
|
// sendMsg sends a control message from contorl channels message queue
|
|
func (cc *controlChannel) sendMsg() (err error) {
|
|
if len(cc.msgQueue) < 1 {
|
|
return nil
|
|
}
|
|
// Get message buffer
|
|
msg := cc.msgQueue[0]
|
|
// Dequeue
|
|
cc.msgQueue = cc.msgQueue[1:]
|
|
|
|
iov := &syscall.Iovec{
|
|
Base: &msg.Buffer.Bytes()[0],
|
|
Len: msgSize,
|
|
}
|
|
|
|
msgh := syscall.Msghdr{
|
|
Iov: iov,
|
|
Iovlen: 1,
|
|
}
|
|
|
|
if msg.Fd > 0 {
|
|
oob := syscall.UnixRights(msg.Fd)
|
|
msgh.Control = &oob[0]
|
|
msgh.Controllen = uint64(syscall.CmsgSpace(4))
|
|
}
|
|
|
|
_, _, errno := syscall.Syscall(syscall.SYS_SENDMSG, uintptr(cc.event.Fd), uintptr(unsafe.Pointer(&msgh)), uintptr(0))
|
|
if errno != 0 {
|
|
err = os.NewSyscallError("sendmsg", errno)
|
|
return fmt.Errorf("SYS_SENDMSG: %s", errno)
|
|
}
|
|
|
|
return nil
|
|
}
|