func Exist(dirpath string) bool {
names, err := fileutil.ReadDir(dirpath)
if err != nil {
return false
}
return len(names) != 0
}
// identifyDataDirOrDie returns the type of the data dir.
// Dies if the datadir is invalid.
func identifyDataDirOrDie(dir string) dirType {
names, err := fileutil.ReadDir(dir)
if err != nil {
if os.IsNotExist(err) {
return dirEmpty
}
log.Fatalf("etcd: error listing data dir: %s", dir)
}
var m, p bool
for _, name := range names {
switch dirType(name) {
case dirMember:
m = true
case dirProxy:
p = true
default:
log.Printf("etcd: found invalid file/dir %s under data dir %s (Ignore this if you are upgrading etcd)", name, dir)
}
}
if m && p {
log.Fatal("etcd: invalid datadir. Both member and proxy directories exist.")
}
if m {
return dirMember
}
if p {
return dirProxy
}
return dirEmpty
}
func DetectVersion(dirpath string) (WalVersion, error) {
names, err := fileutil.ReadDir(dirpath)
if err != nil {
if os.IsNotExist(err) {
err = nil
}
// Error reading the directory
return WALNotExist, err
}
if len(names) == 0 {
// Empty WAL directory
return WALNotExist, nil
}
nameSet := types.NewUnsafeSet(names...)
if nameSet.Contains("member") {
ver, err := DetectVersion(path.Join(dirpath, "member"))
if ver == WALv2_0 {
return WALv2_0_1, nil
} else if ver == WALv0_4 {
// How in the blazes did it get there?
return WALUnknown, nil
}
return ver, err
}
if nameSet.ContainsAll([]string{"snap", "wal"}) {
// .../wal cannot be empty to exist.
if Exist(path.Join(dirpath, "wal")) {
return WALv2_0, nil
}
}
if nameSet.ContainsAll([]string{"proxy"}) {
return WALv2_0Proxy, nil
}
if nameSet.ContainsAll([]string{"snapshot", "conf", "log"}) {
return WALv0_4, nil
}
if nameSet.ContainsAll([]string{"standby_info"}) {
return WALv0_4, nil
}
return WALUnknown, nil
}