1 files changed, 135 insertions, 0 deletions
diff --git a/vendor/github.com/nxadm/tail/watch/inotify.go b/vendor/github.com/nxadm/tail/watch/inotify.go
new file mode 100644
index 000000000..439921810
--- /dev/null
+++ b/vendor/github.com/nxadm/tail/watch/inotify.go
@@ -0,0 +1,135 @@
+// 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/nxadm/tail/util"
+
+    "github.com/fsnotify/fsnotify"
+	"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() {
+
+		events := Events(fw.Filename)
+
+		for {
+			prevSize := fw.Size
+
+			var evt fsnotify.Event
+			var ok bool
+
+			select {
+			case evt, ok = <-events:
+				if !ok {
+					RemoveWatch(fw.Filename)
+					return
+				}
+			case <-t.Dying():
+				RemoveWatch(fw.Filename)
+				return
+			}
+
+			switch {
+			case evt.Op&fsnotify.Remove == fsnotify.Remove:
+				fallthrough
+
+			case evt.Op&fsnotify.Rename == fsnotify.Rename:
+				RemoveWatch(fw.Filename)
+				changes.NotifyDeleted()
+				return
+
+			//With an open fd, unlink(fd) - inotify returns IN_ATTRIB (==fsnotify.Chmod)
+			case evt.Op&fsnotify.Chmod == fsnotify.Chmod:
+				fallthrough
+
+			case evt.Op&fsnotify.Write == fsnotify.Write:
+				fi, err := os.Stat(fw.Filename)
+				if err != nil {
+					if os.IsNotExist(err) {
+						RemoveWatch(fw.Filename)
+						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
+}