github.com/fafucoder/cilium@v1.6.11/pkg/monitor/ifindex.go (about)

     1  // Copyright 2018 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package monitor
    16  
    17  import (
    18  	"fmt"
    19  	"time"
    20  
    21  	"github.com/cilium/cilium/pkg/lock"
    22  
    23  	"github.com/vishvananda/netlink"
    24  )
    25  
    26  type linkMap map[int]string
    27  
    28  var (
    29  	ifindexMap = linkMap{}
    30  	mutex      lock.RWMutex
    31  )
    32  
    33  func ifname(ifindex int) string {
    34  	mutex.RLock()
    35  	defer mutex.RUnlock()
    36  
    37  	if name, ok := ifindexMap[ifindex]; ok {
    38  		return name
    39  	}
    40  
    41  	return fmt.Sprintf("%d", ifindex)
    42  }
    43  
    44  func init() {
    45  	go func() {
    46  		for {
    47  			newMap := linkMap{}
    48  
    49  			links, err := netlink.LinkList()
    50  			if err != nil {
    51  				goto sleep
    52  			}
    53  
    54  			for _, link := range links {
    55  				newMap[link.Attrs().Index] = link.Attrs().Name
    56  			}
    57  
    58  			mutex.Lock()
    59  			ifindexMap = newMap
    60  			mutex.Unlock()
    61  
    62  		sleep:
    63  			time.Sleep(time.Duration(15) * time.Second)
    64  		}
    65  
    66  	}()
    67  }