116 lines
2.7 KiB
Go
116 lines
2.7 KiB
Go
// Copyright 2015 CNI authors
|
|
//
|
|
// 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 disk
|
|
|
|
import (
|
|
"io/ioutil"
|
|
"net"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
|
|
"github.com/containernetworking/cni/plugins/ipam/host-local/backend"
|
|
)
|
|
|
|
const lastIPFile = "last_reserved_ip"
|
|
|
|
var defaultDataDir = "/var/lib/cni/networks"
|
|
|
|
type Store struct {
|
|
FileLock
|
|
dataDir string
|
|
}
|
|
|
|
// Store implements the Store interface
|
|
var _ backend.Store = &Store{}
|
|
|
|
func New(network, dataDir string) (*Store, error) {
|
|
if dataDir == "" {
|
|
dataDir = defaultDataDir
|
|
}
|
|
dir := filepath.Join(dataDir, network)
|
|
if err := os.MkdirAll(dir, 0644); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
lk, err := NewFileLock(dir)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &Store{*lk, dir}, nil
|
|
}
|
|
|
|
func (s *Store) Reserve(id string, ip net.IP) (bool, error) {
|
|
fname := filepath.Join(s.dataDir, ip.String())
|
|
f, err := os.OpenFile(fname, os.O_RDWR|os.O_EXCL|os.O_CREATE, 0644)
|
|
if os.IsExist(err) {
|
|
return false, nil
|
|
}
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
if _, err := f.WriteString(strings.TrimSpace(id)); err != nil {
|
|
f.Close()
|
|
os.Remove(f.Name())
|
|
return false, err
|
|
}
|
|
if err := f.Close(); err != nil {
|
|
os.Remove(f.Name())
|
|
return false, err
|
|
}
|
|
// store the reserved ip in lastIPFile
|
|
ipfile := filepath.Join(s.dataDir, lastIPFile)
|
|
err = ioutil.WriteFile(ipfile, []byte(ip.String()), 0644)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
return true, nil
|
|
}
|
|
|
|
// LastReservedIP returns the last reserved IP if exists
|
|
func (s *Store) LastReservedIP() (net.IP, error) {
|
|
ipfile := filepath.Join(s.dataDir, lastIPFile)
|
|
data, err := ioutil.ReadFile(ipfile)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return net.ParseIP(string(data)), nil
|
|
}
|
|
|
|
func (s *Store) Release(ip net.IP) error {
|
|
return os.Remove(filepath.Join(s.dataDir, ip.String()))
|
|
}
|
|
|
|
// N.B. This function eats errors to be tolerant and
|
|
// release as much as possible
|
|
func (s *Store) ReleaseByID(id string) error {
|
|
err := filepath.Walk(s.dataDir, func(path string, info os.FileInfo, err error) error {
|
|
if err != nil || info.IsDir() {
|
|
return nil
|
|
}
|
|
data, err := ioutil.ReadFile(path)
|
|
if err != nil {
|
|
return nil
|
|
}
|
|
if strings.TrimSpace(string(data)) == strings.TrimSpace(id) {
|
|
if err := os.Remove(path); err != nil {
|
|
return nil
|
|
}
|
|
}
|
|
return nil
|
|
})
|
|
return err
|
|
}
|