diff options
Diffstat (limited to 'vendor/github.com/hpcloud/tail/watch/inotify.go')
-rw-r--r-- | vendor/github.com/hpcloud/tail/watch/inotify.go | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/vendor/github.com/hpcloud/tail/watch/inotify.go b/vendor/github.com/hpcloud/tail/watch/inotify.go new file mode 100644 index 000000000..4478f1e1a --- /dev/null +++ b/vendor/github.com/hpcloud/tail/watch/inotify.go @@ -0,0 +1,128 @@ +// Copyright (c) 2015 HPE Software Inc. All rights reserved. +// Copyright (c) 2013 ActiveState Software Inc. All rights reserved. + +package watch + +import ( + "fmt" + "os" + "path/filepath" + + "github.com/hpcloud/tail/util" + + "gopkg.in/fsnotify.v1" + "gopkg.in/tomb.v1" +) + +// InotifyFileWatcher uses inotify to monitor file changes. +type InotifyFileWatcher struct { + Filename string + Size int64 +} + +func NewInotifyFileWatcher(filename string) *InotifyFileWatcher { + fw := &InotifyFileWatcher{filepath.Clean(filename), 0} + return fw +} + +func (fw *InotifyFileWatcher) BlockUntilExists(t *tomb.Tomb) error { + err := WatchCreate(fw.Filename) + if err != nil { + return err + } + defer RemoveWatchCreate(fw.Filename) + + // Do a real check now as the file might have been created before + // calling `WatchFlags` above. + if _, err = os.Stat(fw.Filename); !os.IsNotExist(err) { + // file exists, or stat returned an error. + return err + } + + events := Events(fw.Filename) + + for { + select { + case evt, ok := <-events: + if !ok { + return fmt.Errorf("inotify watcher has been closed") + } + evtName, err := filepath.Abs(evt.Name) + if err != nil { + return err + } + fwFilename, err := filepath.Abs(fw.Filename) + if err != nil { + return err + } + if evtName == fwFilename { + return nil + } + case <-t.Dying(): + return tomb.ErrDying + } + } + panic("unreachable") +} + +func (fw *InotifyFileWatcher) ChangeEvents(t *tomb.Tomb, pos int64) (*FileChanges, error) { + err := Watch(fw.Filename) + if err != nil { + return nil, err + } + + changes := NewFileChanges() + fw.Size = pos + + go func() { + defer RemoveWatch(fw.Filename) + + events := Events(fw.Filename) + + for { + prevSize := fw.Size + + var evt fsnotify.Event + var ok bool + + select { + case evt, ok = <-events: + if !ok { + return + } + case <-t.Dying(): + return + } + + switch { + case evt.Op&fsnotify.Remove == fsnotify.Remove: + fallthrough + + case evt.Op&fsnotify.Rename == fsnotify.Rename: + changes.NotifyDeleted() + return + + case evt.Op&fsnotify.Write == fsnotify.Write: + fi, err := os.Stat(fw.Filename) + if err != nil { + if os.IsNotExist(err) { + changes.NotifyDeleted() + return + } + // XXX: report this error back to the user + util.Fatal("Failed to stat file %v: %v", fw.Filename, err) + } + fw.Size = fi.Size() + + if prevSize > 0 && prevSize > fw.Size { + changes.NotifyTruncated() + } else { + changes.NotifyModified() + } + prevSize = fw.Size + } + } + }() + + return changes, nil +} |