github.com/go-spring/spring-base@v1.1.3/util/net.go (about)

     1  /*
     2   * Copyright 2012-2019 the original author or authors.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *      https://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  package util
    18  
    19  import (
    20  	"net"
    21  	"sync"
    22  )
    23  
    24  var localIPv4Str = "0.0.0.0"
    25  var localIPv4Once = new(sync.Once)
    26  
    27  // LocalIPv4 returns the IPv4 address of the local computer.
    28  func LocalIPv4() string {
    29  	localIPv4Once.Do(func() {
    30  		if ias, err := net.InterfaceAddrs(); err == nil {
    31  			for _, address := range ias {
    32  				if ipNet, ok := address.(*net.IPNet); ok && !ipNet.IP.IsLoopback() {
    33  					if ipNet.IP.To4() != nil {
    34  						localIPv4Str = ipNet.IP.String()
    35  						return
    36  					}
    37  				}
    38  			}
    39  		}
    40  	})
    41  	return localIPv4Str
    42  }