sslobodr | d046be8 | 2019-01-16 10:02:22 -0500 | [diff] [blame] | 1 | // Copyright 2015 The etcd Authors |
| 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 fileutil |
| 16 | |
| 17 | import ( |
| 18 | "os" |
| 19 | "path/filepath" |
| 20 | "sort" |
| 21 | "strings" |
| 22 | "time" |
| 23 | ) |
| 24 | |
| 25 | func PurgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error { |
| 26 | return purgeFile(dirname, suffix, max, interval, stop, nil) |
| 27 | } |
| 28 | |
| 29 | // purgeFile is the internal implementation for PurgeFile which can post purged files to purgec if non-nil. |
| 30 | func purgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}, purgec chan<- string) <-chan error { |
| 31 | errC := make(chan error, 1) |
| 32 | go func() { |
| 33 | for { |
| 34 | fnames, err := ReadDir(dirname) |
| 35 | if err != nil { |
| 36 | errC <- err |
| 37 | return |
| 38 | } |
| 39 | newfnames := make([]string, 0) |
| 40 | for _, fname := range fnames { |
| 41 | if strings.HasSuffix(fname, suffix) { |
| 42 | newfnames = append(newfnames, fname) |
| 43 | } |
| 44 | } |
| 45 | sort.Strings(newfnames) |
| 46 | fnames = newfnames |
| 47 | for len(newfnames) > int(max) { |
| 48 | f := filepath.Join(dirname, newfnames[0]) |
| 49 | l, err := TryLockFile(f, os.O_WRONLY, PrivateFileMode) |
| 50 | if err != nil { |
| 51 | break |
| 52 | } |
| 53 | if err = os.Remove(f); err != nil { |
| 54 | errC <- err |
| 55 | return |
| 56 | } |
| 57 | if err = l.Close(); err != nil { |
| 58 | plog.Errorf("error unlocking %s when purging file (%v)", l.Name(), err) |
| 59 | errC <- err |
| 60 | return |
| 61 | } |
| 62 | plog.Infof("purged file %s successfully", f) |
| 63 | newfnames = newfnames[1:] |
| 64 | } |
| 65 | if purgec != nil { |
| 66 | for i := 0; i < len(fnames)-len(newfnames); i++ { |
| 67 | purgec <- fnames[i] |
| 68 | } |
| 69 | } |
| 70 | select { |
| 71 | case <-time.After(interval): |
| 72 | case <-stop: |
| 73 | return |
| 74 | } |
| 75 | } |
| 76 | }() |
| 77 | return errC |
| 78 | } |