Initial checkin from CRI-O repo

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

15 files changed, 1373 insertions, 0 deletions

diff --git a/vendor/github.com/hpcloud/tail/LICENSE.txt b/vendor/github.com/hpcloud/tail/LICENSE.txt
new file mode 100644
index 000000000..818d802a5
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/LICENSE.txt
@@ -0,0 +1,21 @@
+# The MIT License (MIT)
+
+# © Copyright 2015 Hewlett Packard Enterprise Development LP
+Copyright (c) 2014 ActiveState
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/vendor/github.com/hpcloud/tail/README.md b/vendor/github.com/hpcloud/tail/README.md
new file mode 100644
index 000000000..fb7fbc26c
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/README.md
@@ -0,0 +1,28 @@
+[![Build Status](https://travis-ci.org/hpcloud/tail.svg)](https://travis-ci.org/hpcloud/tail)
+[![Build status](https://ci.appveyor.com/api/projects/status/kohpsf3rvhjhrox6?svg=true)](https://ci.appveyor.com/project/HelionCloudFoundry/tail) 
+
+# Go package for tail-ing files
+
+A Go package striving to emulate the features of the BSD `tail` program. 
+
+```Go
+t, err := tail.TailFile("/var/log/nginx.log", tail.Config{Follow: true})
+for line := range t.Lines {
+    fmt.Println(line.Text)
+}
+```
+
+See [API documentation](http://godoc.org/github.com/hpcloud/tail).
+
+## Log rotation
+
+Tail comes with full support for truncation/move detection as it is
+designed to work with log rotation tools.
+
+## Installing
+
+    go get github.com/hpcloud/tail/...
+
+## Windows support
+
+This package [needs assistance](https://github.com/hpcloud/tail/labels/Windows) for full Windows support.
diff --git a/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go b/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go
new file mode 100644
index 000000000..358b69e7f
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go
@@ -0,0 +1,97 @@
+// Package ratelimiter implements the Leaky Bucket ratelimiting algorithm with memcached and in-memory backends.
+package ratelimiter
+
+import (
+	"time"
+)
+
+type LeakyBucket struct {
+	Size         uint16
+	Fill         float64
+	LeakInterval time.Duration // time.Duration for 1 unit of size to leak
+	Lastupdate   time.Time
+	Now          func() time.Time
+}
+
+func NewLeakyBucket(size uint16, leakInterval time.Duration) *LeakyBucket {
+	bucket := LeakyBucket{
+		Size:         size,
+		Fill:         0,
+		LeakInterval: leakInterval,
+		Now:          time.Now,
+		Lastupdate:   time.Now(),
+	}
+
+	return &bucket
+}
+
+func (b *LeakyBucket) updateFill() {
+	now := b.Now()
+	if b.Fill > 0 {
+		elapsed := now.Sub(b.Lastupdate)
+
+		b.Fill -= float64(elapsed) / float64(b.LeakInterval)
+		if b.Fill < 0 {
+			b.Fill = 0
+		}
+	}
+	b.Lastupdate = now
+}
+
+func (b *LeakyBucket) Pour(amount uint16) bool {
+	b.updateFill()
+
+	var newfill float64 = b.Fill + float64(amount)
+
+	if newfill > float64(b.Size) {
+		return false
+	}
+
+	b.Fill = newfill
+
+	return true
+}
+
+// The time at which this bucket will be completely drained
+func (b *LeakyBucket) DrainedAt() time.Time {
+	return b.Lastupdate.Add(time.Duration(b.Fill * float64(b.LeakInterval)))
+}
+
+// The duration until this bucket is completely drained
+func (b *LeakyBucket) TimeToDrain() time.Duration {
+	return b.DrainedAt().Sub(b.Now())
+}
+
+func (b *LeakyBucket) TimeSinceLastUpdate() time.Duration {
+	return b.Now().Sub(b.Lastupdate)
+}
+
+type LeakyBucketSer struct {
+	Size         uint16
+	Fill         float64
+	LeakInterval time.Duration // time.Duration for 1 unit of size to leak
+	Lastupdate   time.Time
+}
+
+func (b *LeakyBucket) Serialise() *LeakyBucketSer {
+	bucket := LeakyBucketSer{
+		Size:         b.Size,
+		Fill:         b.Fill,
+		LeakInterval: b.LeakInterval,
+		Lastupdate:   b.Lastupdate,
+	}
+
+	return &bucket
+}
+
+func (b *LeakyBucketSer) DeSerialise() *LeakyBucket {
+	bucket := LeakyBucket{
+		Size:         b.Size,
+		Fill:         b.Fill,
+		LeakInterval: b.LeakInterval,
+		Lastupdate:   b.Lastupdate,
+		Now:          time.Now,
+	}
+
+	return &bucket
+}
diff --git a/vendor/github.com/hpcloud/tail/ratelimiter/memory.go b/vendor/github.com/hpcloud/tail/ratelimiter/memory.go
new file mode 100644
index 000000000..8f6a5784a
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/ratelimiter/memory.go
@@ -0,0 +1,58 @@
+package ratelimiter
+
+import (
+	"errors"
+	"time"
+)
+
+const GC_SIZE int = 100
+
+type Memory struct {
+	store           map[string]LeakyBucket
+	lastGCCollected time.Time
+}
+
+func NewMemory() *Memory {
+	m := new(Memory)
+	m.store = make(map[string]LeakyBucket)
+	m.lastGCCollected = time.Now()
+	return m
+}
+
+func (m *Memory) GetBucketFor(key string) (*LeakyBucket, error) {
+
+	bucket, ok := m.store[key]
+	if !ok {
+		return nil, errors.New("miss")
+	}
+
+	return &bucket, nil
+}
+
+func (m *Memory) SetBucketFor(key string, bucket LeakyBucket) error {
+
+	if len(m.store) > GC_SIZE {
+		m.GarbageCollect()
+	}
+
+	m.store[key] = bucket
+
+	return nil
+}
+
+func (m *Memory) GarbageCollect() {
+	now := time.Now()
+
+	// rate limit GC to once per minute
+	if now.Add(60*time.Second).Unix() > m.lastGCCollected.Unix() {
+
+		for key, bucket := range m.store {
+			// if the bucket is drained, then GC
+			if bucket.DrainedAt().Unix() > now.Unix() {
+				delete(m.store, key)
+			}
+		}
+
+		m.lastGCCollected = now
+	}
+}
diff --git a/vendor/github.com/hpcloud/tail/ratelimiter/storage.go b/vendor/github.com/hpcloud/tail/ratelimiter/storage.go
new file mode 100644
index 000000000..89b2fe882
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/ratelimiter/storage.go
@@ -0,0 +1,6 @@
+package ratelimiter
+
+type Storage interface {
+	GetBucketFor(string) (*LeakyBucket, error)
+	SetBucketFor(string, LeakyBucket) error
+}
diff --git a/vendor/github.com/hpcloud/tail/tail.go b/vendor/github.com/hpcloud/tail/tail.go
new file mode 100644
index 000000000..2d252d605
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/tail.go
@@ -0,0 +1,438 @@
+// Copyright (c) 2015 HPE Software Inc. All rights reserved.
+// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
+
+package tail
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/hpcloud/tail/ratelimiter"
+	"github.com/hpcloud/tail/util"
+	"github.com/hpcloud/tail/watch"
+	"gopkg.in/tomb.v1"
+)
+
+var (
+	ErrStop = fmt.Errorf("tail should now stop")
+)
+
+type Line struct {
+	Text string
+	Time time.Time
+	Err  error // Error from tail
+}
+
+// NewLine returns a Line with present time.
+func NewLine(text string) *Line {
+	return &Line{text, time.Now(), nil}
+}
+
+// SeekInfo represents arguments to `os.Seek`
+type SeekInfo struct {
+	Offset int64
+	Whence int // os.SEEK_*
+}
+
+type logger interface {
+	Fatal(v ...interface{})
+	Fatalf(format string, v ...interface{})
+	Fatalln(v ...interface{})
+	Panic(v ...interface{})
+	Panicf(format string, v ...interface{})
+	Panicln(v ...interface{})
+	Print(v ...interface{})
+	Printf(format string, v ...interface{})
+	Println(v ...interface{})
+}
+
+// Config is used to specify how a file must be tailed.
+type Config struct {
+	// File-specifc
+	Location    *SeekInfo // Seek to this location before tailing
+	ReOpen      bool      // Reopen recreated files (tail -F)
+	MustExist   bool      // Fail early if the file does not exist
+	Poll        bool      // Poll for file changes instead of using inotify
+	Pipe        bool      // Is a named pipe (mkfifo)
+	RateLimiter *ratelimiter.LeakyBucket
+
+	// Generic IO
+	Follow      bool // Continue looking for new lines (tail -f)
+	MaxLineSize int  // If non-zero, split longer lines into multiple lines
+
+	// Logger, when nil, is set to tail.DefaultLogger
+	// To disable logging: set field to tail.DiscardingLogger
+	Logger logger
+}
+
+type Tail struct {
+	Filename string
+	Lines    chan *Line
+	Config
+
+	file   *os.File
+	reader *bufio.Reader
+
+	watcher watch.FileWatcher
+	changes *watch.FileChanges
+
+	tomb.Tomb // provides: Done, Kill, Dying
+
+	lk sync.Mutex
+}
+
+var (
+	// DefaultLogger is used when Config.Logger == nil
+	DefaultLogger = log.New(os.Stderr, "", log.LstdFlags)
+	// DiscardingLogger can be used to disable logging output
+	DiscardingLogger = log.New(ioutil.Discard, "", 0)
+)
+
+// TailFile begins tailing the file. Output stream is made available
+// via the `Tail.Lines` channel. To handle errors during tailing,
+// invoke the `Wait` or `Err` method after finishing reading from the
+// `Lines` channel.
+func TailFile(filename string, config Config) (*Tail, error) {
+	if config.ReOpen && !config.Follow {
+		util.Fatal("cannot set ReOpen without Follow.")
+	}
+
+	t := &Tail{
+		Filename: filename,
+		Lines:    make(chan *Line),
+		Config:   config,
+	}
+
+	// when Logger was not specified in config, use default logger
+	if t.Logger == nil {
+		t.Logger = log.New(os.Stderr, "", log.LstdFlags)
+	}
+
+	if t.Poll {
+		t.watcher = watch.NewPollingFileWatcher(filename)
+	} else {
+		t.watcher = watch.NewInotifyFileWatcher(filename)
+	}
+
+	if t.MustExist {
+		var err error
+		t.file, err = OpenFile(t.Filename)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	go t.tailFileSync()
+
+	return t, nil
+}
+
+// Return the file's current position, like stdio's ftell().
+// But this value is not very accurate.
+// it may readed one line in the chan(tail.Lines),
+// so it may lost one line.
+func (tail *Tail) Tell() (offset int64, err error) {
+	if tail.file == nil {
+		return
+	}
+	offset, err = tail.file.Seek(0, os.SEEK_CUR)
+	if err != nil {
+		return
+	}
+
+	tail.lk.Lock()
+	defer tail.lk.Unlock()
+	if tail.reader == nil {
+		return
+	}
+
+	offset -= int64(tail.reader.Buffered())
+	return
+}
+
+// Stop stops the tailing activity.
+func (tail *Tail) Stop() error {
+	tail.Kill(nil)
+	return tail.Wait()
+}
+
+// StopAtEOF stops tailing as soon as the end of the file is reached.
+func (tail *Tail) StopAtEOF() error {
+	tail.Kill(errStopAtEOF)
+	return tail.Wait()
+}
+
+var errStopAtEOF = errors.New("tail: stop at eof")
+
+func (tail *Tail) close() {
+	close(tail.Lines)
+	tail.closeFile()
+}
+
+func (tail *Tail) closeFile() {
+	if tail.file != nil {
+		tail.file.Close()
+		tail.file = nil
+	}
+}
+
+func (tail *Tail) reopen() error {
+	tail.closeFile()
+	for {
+		var err error
+		tail.file, err = OpenFile(tail.Filename)
+		if err != nil {
+			if os.IsNotExist(err) {
+				tail.Logger.Printf("Waiting for %s to appear...", tail.Filename)
+				if err := tail.watcher.BlockUntilExists(&tail.Tomb); err != nil {
+					if err == tomb.ErrDying {
+						return err
+					}
+					return fmt.Errorf("Failed to detect creation of %s: %s", tail.Filename, err)
+				}
+				continue
+			}
+			return fmt.Errorf("Unable to open file %s: %s", tail.Filename, err)
+		}
+		break
+	}
+	return nil
+}
+
+func (tail *Tail) readLine() (string, error) {
+	tail.lk.Lock()
+	line, err := tail.reader.ReadString('\n')
+	tail.lk.Unlock()
+	if err != nil {
+		// Note ReadString "returns the data read before the error" in
+		// case of an error, including EOF, so we return it as is. The
+		// caller is expected to process it if err is EOF.
+		return line, err
+	}
+
+	line = strings.TrimRight(line, "\n")
+
+	return line, err
+}
+
+func (tail *Tail) tailFileSync() {
+	defer tail.Done()
+	defer tail.close()
+
+	if !tail.MustExist {
+		// deferred first open.
+		err := tail.reopen()
+		if err != nil {
+			if err != tomb.ErrDying {
+				tail.Kill(err)
+			}
+			return
+		}
+	}
+
+	// Seek to requested location on first open of the file.
+	if tail.Location != nil {
+		_, err := tail.file.Seek(tail.Location.Offset, tail.Location.Whence)
+		tail.Logger.Printf("Seeked %s - %+v\n", tail.Filename, tail.Location)
+		if err != nil {
+			tail.Killf("Seek error on %s: %s", tail.Filename, err)
+			return
+		}
+	}
+
+	tail.openReader()
+
+	var offset int64 = 0
+	var err error
+
+	// Read line by line.
+	for {
+		// do not seek in named pipes
+		if !tail.Pipe {
+			// grab the position in case we need to back up in the event of a half-line
+			offset, err = tail.Tell()
+			if err != nil {
+				tail.Kill(err)
+				return
+			}
+		}
+
+		line, err := tail.readLine()
+
+		// Process `line` even if err is EOF.
+		if err == nil {
+			cooloff := !tail.sendLine(line)
+			if cooloff {
+				// Wait a second before seeking till the end of
+				// file when rate limit is reached.
+				msg := fmt.Sprintf(
+					"Too much log activity; waiting a second " +
+						"before resuming tailing")
+				tail.Lines <- &Line{msg, time.Now(), fmt.Errorf(msg)}
+				select {
+				case <-time.After(time.Second):
+				case <-tail.Dying():
+					return
+				}
+				if err := tail.seekEnd(); err != nil {
+					tail.Kill(err)
+					return
+				}
+			}
+		} else if err == io.EOF {
+			if !tail.Follow {
+				if line != "" {
+					tail.sendLine(line)
+				}
+				return
+			}
+
+			if tail.Follow && line != "" {
+				// this has the potential to never return the last line if
+				// it's not followed by a newline; seems a fair trade here
+				err := tail.seekTo(SeekInfo{Offset: offset, Whence: 0})
+				if err != nil {
+					tail.Kill(err)
+					return
+				}
+			}
+
+			// When EOF is reached, wait for more data to become
+			// available. Wait strategy is based on the `tail.watcher`
+			// implementation (inotify or polling).
+			err := tail.waitForChanges()
+			if err != nil {
+				if err != ErrStop {
+					tail.Kill(err)
+				}
+				return
+			}
+		} else {
+			// non-EOF error
+			tail.Killf("Error reading %s: %s", tail.Filename, err)
+			return
+		}
+
+		select {
+		case <-tail.Dying():
+			if tail.Err() == errStopAtEOF {
+				continue
+			}
+			return
+		default:
+		}
+	}
+}
+
+// waitForChanges waits until the file has been appended, deleted,
+// moved or truncated. When moved or deleted - the file will be
+// reopened if ReOpen is true. Truncated files are always reopened.
+func (tail *Tail) waitForChanges() error {
+	if tail.changes == nil {
+		pos, err := tail.file.Seek(0, os.SEEK_CUR)
+		if err != nil {
+			return err
+		}
+		tail.changes, err = tail.watcher.ChangeEvents(&tail.Tomb, pos)
+		if err != nil {
+			return err
+		}
+	}
+
+	select {
+	case <-tail.changes.Modified:
+		return nil
+	case <-tail.changes.Deleted:
+		tail.changes = nil
+		if tail.ReOpen {
+			// XXX: we must not log from a library.
+			tail.Logger.Printf("Re-opening moved/deleted file %s ...", tail.Filename)
+			if err := tail.reopen(); err != nil {
+				return err
+			}
+			tail.Logger.Printf("Successfully reopened %s", tail.Filename)
+			tail.openReader()
+			return nil
+		} else {
+			tail.Logger.Printf("Stopping tail as file no longer exists: %s", tail.Filename)
+			return ErrStop
+		}
+	case <-tail.changes.Truncated:
+		// Always reopen truncated files (Follow is true)
+		tail.Logger.Printf("Re-opening truncated file %s ...", tail.Filename)
+		if err := tail.reopen(); err != nil {
+			return err
+		}
+		tail.Logger.Printf("Successfully reopened truncated %s", tail.Filename)
+		tail.openReader()
+		return nil
+	case <-tail.Dying():
+		return ErrStop
+	}
+	panic("unreachable")
+}
+
+func (tail *Tail) openReader() {
+	if tail.MaxLineSize > 0 {
+		// add 2 to account for newline characters
+		tail.reader = bufio.NewReaderSize(tail.file, tail.MaxLineSize+2)
+	} else {
+		tail.reader = bufio.NewReader(tail.file)
+	}
+}
+
+func (tail *Tail) seekEnd() error {
+	return tail.seekTo(SeekInfo{Offset: 0, Whence: os.SEEK_END})
+}
+
+func (tail *Tail) seekTo(pos SeekInfo) error {
+	_, err := tail.file.Seek(pos.Offset, pos.Whence)
+	if err != nil {
+		return fmt.Errorf("Seek error on %s: %s", tail.Filename, err)
+	}
+	// Reset the read buffer whenever the file is re-seek'ed
+	tail.reader.Reset(tail.file)
+	return nil
+}
+
+// sendLine sends the line(s) to Lines channel, splitting longer lines
+// if necessary. Return false if rate limit is reached.
+func (tail *Tail) sendLine(line string) bool {
+	now := time.Now()
+	lines := []string{line}
+
+	// Split longer lines
+	if tail.MaxLineSize > 0 && len(line) > tail.MaxLineSize {
+		lines = util.PartitionString(line, tail.MaxLineSize)
+	}
+
+	for _, line := range lines {
+		tail.Lines <- &Line{line, now, nil}
+	}
+
+	if tail.Config.RateLimiter != nil {
+		ok := tail.Config.RateLimiter.Pour(uint16(len(lines)))
+		if !ok {
+			tail.Logger.Printf("Leaky bucket full (%v); entering 1s cooloff period.\n",
+				tail.Filename)
+			return false
+		}
+	}
+
+	return true
+}
+
+// Cleanup removes inotify watches added by the tail package. This function is
+// meant to be invoked from a process's exit handler. Linux kernel may not
+// automatically remove inotify watches after the process exits.
+func (tail *Tail) Cleanup() {
+	watch.Cleanup(tail.Filename)
+}
diff --git a/vendor/github.com/hpcloud/tail/tail_posix.go b/vendor/github.com/hpcloud/tail/tail_posix.go
new file mode 100644
index 000000000..bc4dc3357
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/tail_posix.go
@@ -0,0 +1,11 @@
+// +build linux darwin freebsd netbsd openbsd
+
+package tail
+
+import (
+	"os"
+)
+
+func OpenFile(name string) (file *os.File, err error) {
+	return os.Open(name)
+}
diff --git a/vendor/github.com/hpcloud/tail/tail_windows.go b/vendor/github.com/hpcloud/tail/tail_windows.go
new file mode 100644
index 000000000..ef2cfca1b
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/tail_windows.go
@@ -0,0 +1,12 @@
+// +build windows
+
+package tail
+
+import (
+	"github.com/hpcloud/tail/winfile"
+	"os"
+)
+
+func OpenFile(name string) (file *os.File, err error) {
+	return winfile.OpenFile(name, os.O_RDONLY, 0)
+}
diff --git a/vendor/github.com/hpcloud/tail/util/util.go b/vendor/github.com/hpcloud/tail/util/util.go
new file mode 100644
index 000000000..54151fe39
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/util/util.go
@@ -0,0 +1,48 @@
+// Copyright (c) 2015 HPE Software Inc. All rights reserved.
+// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
+
+package util
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"runtime/debug"
+)
+
+type Logger struct {
+	*log.Logger
+}
+
+var LOGGER = &Logger{log.New(os.Stderr, "", log.LstdFlags)}
+
+// fatal is like panic except it displays only the current goroutine's stack.
+func Fatal(format string, v ...interface{}) {
+	// https://github.com/hpcloud/log/blob/master/log.go#L45
+	LOGGER.Output(2, fmt.Sprintf("FATAL -- "+format, v...)+"\n"+string(debug.Stack()))
+	os.Exit(1)
+}
+
+// partitionString partitions the string into chunks of given size,
+// with the last chunk of variable size.
+func PartitionString(s string, chunkSize int) []string {
+	if chunkSize <= 0 {
+		panic("invalid chunkSize")
+	}
+	length := len(s)
+	chunks := 1 + length/chunkSize
+	start := 0
+	end := chunkSize
+	parts := make([]string, 0, chunks)
+	for {
+		if end > length {
+			end = length
+		}
+		parts = append(parts, s[start:end])
+		if end == length {
+			break
+		}
+		start, end = end, end+chunkSize
+	}
+	return parts
+}
diff --git a/vendor/github.com/hpcloud/tail/watch/filechanges.go b/vendor/github.com/hpcloud/tail/watch/filechanges.go
new file mode 100644
index 000000000..3ce5dcecb
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/watch/filechanges.go
@@ -0,0 +1,36 @@
+package watch
+
+type FileChanges struct {
+	Modified  chan bool // Channel to get notified of modifications
+	Truncated chan bool // Channel to get notified of truncations
+	Deleted   chan bool // Channel to get notified of deletions/renames
+}
+
+func NewFileChanges() *FileChanges {
+	return &FileChanges{
+		make(chan bool), make(chan bool), make(chan bool)}
+}
+
+func (fc *FileChanges) NotifyModified() {
+	sendOnlyIfEmpty(fc.Modified)
+}
+
+func (fc *FileChanges) NotifyTruncated() {
+	sendOnlyIfEmpty(fc.Truncated)
+}
+
+func (fc *FileChanges) NotifyDeleted() {
+	sendOnlyIfEmpty(fc.Deleted)
+}
+
+// sendOnlyIfEmpty sends on a bool channel only if the channel has no
+// backlog to be read by other goroutines. This concurrency pattern
+// can be used to notify other goroutines if and only if they are
+// looking for it (i.e., subsequent notifications can be compressed
+// into one).
+func sendOnlyIfEmpty(ch chan bool) {
+	select {
+	case ch <- true:
+	default:
+	}
+}
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
+}
diff --git a/vendor/github.com/hpcloud/tail/watch/inotify_tracker.go b/vendor/github.com/hpcloud/tail/watch/inotify_tracker.go
new file mode 100644
index 000000000..03be4275c
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/watch/inotify_tracker.go
@@ -0,0 +1,260 @@
+// Copyright (c) 2015 HPE Software Inc. All rights reserved.
+// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
+
+package watch
+
+import (
+	"log"
+	"os"
+	"path/filepath"
+	"sync"
+	"syscall"
+
+	"github.com/hpcloud/tail/util"
+
+	"gopkg.in/fsnotify.v1"
+)
+
+type InotifyTracker struct {
+	mux       sync.Mutex
+	watcher   *fsnotify.Watcher
+	chans     map[string]chan fsnotify.Event
+	done      map[string]chan bool
+	watchNums map[string]int
+	watch     chan *watchInfo
+	remove    chan *watchInfo
+	error     chan error
+}
+
+type watchInfo struct {
+	op    fsnotify.Op
+	fname string
+}
+
+func (this *watchInfo) isCreate() bool {
+	return this.op == fsnotify.Create
+}
+
+var (
+	// globally shared InotifyTracker; ensures only one fsnotify.Watcher is used
+	shared *InotifyTracker
+
+	// these are used to ensure the shared InotifyTracker is run exactly once
+	once  = sync.Once{}
+	goRun = func() {
+		shared = &InotifyTracker{
+			mux:       sync.Mutex{},
+			chans:     make(map[string]chan fsnotify.Event),
+			done:      make(map[string]chan bool),
+			watchNums: make(map[string]int),
+			watch:     make(chan *watchInfo),
+			remove:    make(chan *watchInfo),
+			error:     make(chan error),
+		}
+		go shared.run()
+	}
+
+	logger = log.New(os.Stderr, "", log.LstdFlags)
+)
+
+// Watch signals the run goroutine to begin watching the input filename
+func Watch(fname string) error {
+	return watch(&watchInfo{
+		fname: fname,
+	})
+}
+
+// Watch create signals the run goroutine to begin watching the input filename
+// if call the WatchCreate function, don't call the Cleanup, call the RemoveWatchCreate
+func WatchCreate(fname string) error {
+	return watch(&watchInfo{
+		op:    fsnotify.Create,
+		fname: fname,
+	})
+}
+
+func watch(winfo *watchInfo) error {
+	// start running the shared InotifyTracker if not already running
+	once.Do(goRun)
+
+	winfo.fname = filepath.Clean(winfo.fname)
+	shared.watch <- winfo
+	return <-shared.error
+}
+
+// RemoveWatch signals the run goroutine to remove the watch for the input filename
+func RemoveWatch(fname string) {
+	remove(&watchInfo{
+		fname: fname,
+	})
+}
+
+// RemoveWatch create signals the run goroutine to remove the watch for the input filename
+func RemoveWatchCreate(fname string) {
+	remove(&watchInfo{
+		op:    fsnotify.Create,
+		fname: fname,
+	})
+}
+
+func remove(winfo *watchInfo) {
+	// start running the shared InotifyTracker if not already running
+	once.Do(goRun)
+
+	winfo.fname = filepath.Clean(winfo.fname)
+	shared.mux.Lock()
+	done := shared.done[winfo.fname]
+	if done != nil {
+		delete(shared.done, winfo.fname)
+		close(done)
+	}
+
+	fname := winfo.fname
+	if winfo.isCreate() {
+		// Watch for new files to be created in the parent directory.
+		fname = filepath.Dir(fname)
+	}
+	shared.watchNums[fname]--
+	watchNum := shared.watchNums[fname]
+	if watchNum == 0 {
+		delete(shared.watchNums, fname)
+	}
+	shared.mux.Unlock()
+
+	// If we were the last ones to watch this file, unsubscribe from inotify.
+	// This needs to happen after releasing the lock because fsnotify waits
+	// synchronously for the kernel to acknowledge the removal of the watch
+	// for this file, which causes us to deadlock if we still held the lock.
+	if watchNum == 0 {
+		shared.watcher.Remove(fname)
+	}
+	shared.remove <- winfo
+}
+
+// Events returns a channel to which FileEvents corresponding to the input filename
+// will be sent. This channel will be closed when removeWatch is called on this
+// filename.
+func Events(fname string) <-chan fsnotify.Event {
+	shared.mux.Lock()
+	defer shared.mux.Unlock()
+
+	return shared.chans[fname]
+}
+
+// Cleanup removes the watch for the input filename if necessary.
+func Cleanup(fname string) {
+	RemoveWatch(fname)
+}
+
+// watchFlags calls fsnotify.WatchFlags for the input filename and flags, creating
+// a new Watcher if the previous Watcher was closed.
+func (shared *InotifyTracker) addWatch(winfo *watchInfo) error {
+	shared.mux.Lock()
+	defer shared.mux.Unlock()
+
+	if shared.chans[winfo.fname] == nil {
+		shared.chans[winfo.fname] = make(chan fsnotify.Event)
+		shared.done[winfo.fname] = make(chan bool)
+	}
+
+	fname := winfo.fname
+	if winfo.isCreate() {
+		// Watch for new files to be created in the parent directory.
+		fname = filepath.Dir(fname)
+	}
+
+	// already in inotify watch
+	if shared.watchNums[fname] > 0 {
+		shared.watchNums[fname]++
+		if winfo.isCreate() {
+			shared.watchNums[winfo.fname]++
+		}
+		return nil
+	}
+
+	err := shared.watcher.Add(fname)
+	if err == nil {
+		shared.watchNums[fname]++
+		if winfo.isCreate() {
+			shared.watchNums[winfo.fname]++
+		}
+	}
+	return err
+}
+
+// removeWatch calls fsnotify.RemoveWatch for the input filename and closes the
+// corresponding events channel.
+func (shared *InotifyTracker) removeWatch(winfo *watchInfo) {
+	shared.mux.Lock()
+	defer shared.mux.Unlock()
+
+	ch := shared.chans[winfo.fname]
+	if ch == nil {
+		return
+	}
+
+	delete(shared.chans, winfo.fname)
+	close(ch)
+
+	if !winfo.isCreate() {
+		return
+	}
+
+	shared.watchNums[winfo.fname]--
+	if shared.watchNums[winfo.fname] == 0 {
+		delete(shared.watchNums, winfo.fname)
+	}
+}
+
+// sendEvent sends the input event to the appropriate Tail.
+func (shared *InotifyTracker) sendEvent(event fsnotify.Event) {
+	name := filepath.Clean(event.Name)
+
+	shared.mux.Lock()
+	ch := shared.chans[name]
+	done := shared.done[name]
+	shared.mux.Unlock()
+
+	if ch != nil && done != nil {
+		select {
+		case ch <- event:
+		case <-done:
+		}
+	}
+}
+
+// run starts the goroutine in which the shared struct reads events from its
+// Watcher's Event channel and sends the events to the appropriate Tail.
+func (shared *InotifyTracker) run() {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		util.Fatal("failed to create Watcher")
+	}
+	shared.watcher = watcher
+
+	for {
+		select {
+		case winfo := <-shared.watch:
+			shared.error <- shared.addWatch(winfo)
+
+		case winfo := <-shared.remove:
+			shared.removeWatch(winfo)
+
+		case event, open := <-shared.watcher.Events:
+			if !open {
+				return
+			}
+			shared.sendEvent(event)
+
+		case err, open := <-shared.watcher.Errors:
+			if !open {
+				return
+			} else if err != nil {
+				sysErr, ok := err.(*os.SyscallError)
+				if !ok || sysErr.Err != syscall.EINTR {
+					logger.Printf("Error in Watcher Error channel: %s", err)
+				}
+			}
+		}
+	}
+}
diff --git a/vendor/github.com/hpcloud/tail/watch/polling.go b/vendor/github.com/hpcloud/tail/watch/polling.go
new file mode 100644
index 000000000..49491f21d
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/watch/polling.go
@@ -0,0 +1,118 @@
+// Copyright (c) 2015 HPE Software Inc. All rights reserved.
+// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
+
+package watch
+
+import (
+	"os"
+	"runtime"
+	"time"
+
+	"github.com/hpcloud/tail/util"
+	"gopkg.in/tomb.v1"
+)
+
+// PollingFileWatcher polls the file for changes.
+type PollingFileWatcher struct {
+	Filename string
+	Size     int64
+}
+
+func NewPollingFileWatcher(filename string) *PollingFileWatcher {
+	fw := &PollingFileWatcher{filename, 0}
+	return fw
+}
+
+var POLL_DURATION time.Duration
+
+func (fw *PollingFileWatcher) BlockUntilExists(t *tomb.Tomb) error {
+	for {
+		if _, err := os.Stat(fw.Filename); err == nil {
+			return nil
+		} else if !os.IsNotExist(err) {
+			return err
+		}
+		select {
+		case <-time.After(POLL_DURATION):
+			continue
+		case <-t.Dying():
+			return tomb.ErrDying
+		}
+	}
+	panic("unreachable")
+}
+
+func (fw *PollingFileWatcher) ChangeEvents(t *tomb.Tomb, pos int64) (*FileChanges, error) {
+	origFi, err := os.Stat(fw.Filename)
+	if err != nil {
+		return nil, err
+	}
+
+	changes := NewFileChanges()
+	var prevModTime time.Time
+
+	// XXX: use tomb.Tomb to cleanly manage these goroutines. replace
+	// the fatal (below) with tomb's Kill.
+
+	fw.Size = pos
+
+	go func() {
+		prevSize := fw.Size
+		for {
+			select {
+			case <-t.Dying():
+				return
+			default:
+			}
+
+			time.Sleep(POLL_DURATION)
+			fi, err := os.Stat(fw.Filename)
+			if err != nil {
+				// Windows cannot delete a file if a handle is still open (tail keeps one open)
+				// so it gives access denied to anything trying to read it until all handles are released.
+				if os.IsNotExist(err) || (runtime.GOOS == "windows" && os.IsPermission(err)) {
+					// File does not exist (has been deleted).
+					changes.NotifyDeleted()
+					return
+				}
+
+				// XXX: report this error back to the user
+				util.Fatal("Failed to stat file %v: %v", fw.Filename, err)
+			}
+
+			// File got moved/renamed?
+			if !os.SameFile(origFi, fi) {
+				changes.NotifyDeleted()
+				return
+			}
+
+			// File got truncated?
+			fw.Size = fi.Size()
+			if prevSize > 0 && prevSize > fw.Size {
+				changes.NotifyTruncated()
+				prevSize = fw.Size
+				continue
+			}
+			// File got bigger?
+			if prevSize > 0 && prevSize < fw.Size {
+				changes.NotifyModified()
+				prevSize = fw.Size
+				continue
+			}
+			prevSize = fw.Size
+
+			// File was appended to (changed)?
+			modTime := fi.ModTime()
+			if modTime != prevModTime {
+				prevModTime = modTime
+				changes.NotifyModified()
+			}
+		}
+	}()
+
+	return changes, nil
+}
+
+func init() {
+	POLL_DURATION = 250 * time.Millisecond
+}
diff --git a/vendor/github.com/hpcloud/tail/watch/watch.go b/vendor/github.com/hpcloud/tail/watch/watch.go
new file mode 100644
index 000000000..2e1783ef0
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/watch/watch.go
@@ -0,0 +1,20 @@
+// Copyright (c) 2015 HPE Software Inc. All rights reserved.
+// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
+
+package watch
+
+import "gopkg.in/tomb.v1"
+
+// FileWatcher monitors file-level events.
+type FileWatcher interface {
+	// BlockUntilExists blocks until the file comes into existence.
+	BlockUntilExists(*tomb.Tomb) error
+
+	// ChangeEvents reports on changes to a file, be it modification,
+	// deletion, renames or truncations. Returned FileChanges group of
+	// channels will be closed, thus become unusable, after a deletion
+	// or truncation event.
+	// In order to properly report truncations, ChangeEvents requires
+	// the caller to pass their current offset in the file.
+	ChangeEvents(*tomb.Tomb, int64) (*FileChanges, error)
+}
diff --git a/vendor/github.com/hpcloud/tail/winfile/winfile.go b/vendor/github.com/hpcloud/tail/winfile/winfile.go
new file mode 100644
index 000000000..aa7e7bc5d
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/winfile/winfile.go
@@ -0,0 +1,92 @@
+// +build windows
+
+package winfile
+
+import (
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+// issue also described here
+//https://codereview.appspot.com/8203043/
+
+// https://github.com/jnwhiteh/golang/blob/master/src/pkg/syscall/syscall_windows.go#L218
+func Open(path string, mode int, perm uint32) (fd syscall.Handle, err error) {
+	if len(path) == 0 {
+		return syscall.InvalidHandle, syscall.ERROR_FILE_NOT_FOUND
+	}
+	pathp, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return syscall.InvalidHandle, err
+	}
+	var access uint32
+	switch mode & (syscall.O_RDONLY | syscall.O_WRONLY | syscall.O_RDWR) {
+	case syscall.O_RDONLY:
+		access = syscall.GENERIC_READ
+	case syscall.O_WRONLY:
+		access = syscall.GENERIC_WRITE
+	case syscall.O_RDWR:
+		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
+	}
+	if mode&syscall.O_CREAT != 0 {
+		access |= syscall.GENERIC_WRITE
+	}
+	if mode&syscall.O_APPEND != 0 {
+		access &^= syscall.GENERIC_WRITE
+		access |= syscall.FILE_APPEND_DATA
+	}
+	sharemode := uint32(syscall.FILE_SHARE_READ | syscall.FILE_SHARE_WRITE | syscall.FILE_SHARE_DELETE)
+	var sa *syscall.SecurityAttributes
+	if mode&syscall.O_CLOEXEC == 0 {
+		sa = makeInheritSa()
+	}
+	var createmode uint32
+	switch {
+	case mode&(syscall.O_CREAT|syscall.O_EXCL) == (syscall.O_CREAT | syscall.O_EXCL):
+		createmode = syscall.CREATE_NEW
+	case mode&(syscall.O_CREAT|syscall.O_TRUNC) == (syscall.O_CREAT | syscall.O_TRUNC):
+		createmode = syscall.CREATE_ALWAYS
+	case mode&syscall.O_CREAT == syscall.O_CREAT:
+		createmode = syscall.OPEN_ALWAYS
+	case mode&syscall.O_TRUNC == syscall.O_TRUNC:
+		createmode = syscall.TRUNCATE_EXISTING
+	default:
+		createmode = syscall.OPEN_EXISTING
+	}
+	h, e := syscall.CreateFile(pathp, access, sharemode, sa, createmode, syscall.FILE_ATTRIBUTE_NORMAL, 0)
+	return h, e
+}
+
+// https://github.com/jnwhiteh/golang/blob/master/src/pkg/syscall/syscall_windows.go#L211
+func makeInheritSa() *syscall.SecurityAttributes {
+	var sa syscall.SecurityAttributes
+	sa.Length = uint32(unsafe.Sizeof(sa))
+	sa.InheritHandle = 1
+	return &sa
+}
+
+// https://github.com/jnwhiteh/golang/blob/master/src/pkg/os/file_windows.go#L133
+func OpenFile(name string, flag int, perm os.FileMode) (file *os.File, err error) {
+	r, e := Open(name, flag|syscall.O_CLOEXEC, syscallMode(perm))
+	if e != nil {
+		return nil, e
+	}
+	return os.NewFile(uintptr(r), name), nil
+}
+
+// https://github.com/jnwhiteh/golang/blob/master/src/pkg/os/file_posix.go#L61
+func syscallMode(i os.FileMode) (o uint32) {
+	o |= uint32(i.Perm())
+	if i&os.ModeSetuid != 0 {
+		o |= syscall.S_ISUID
+	}
+	if i&os.ModeSetgid != 0 {
+		o |= syscall.S_ISGID
+	}
+	if i&os.ModeSticky != 0 {
+		o |= syscall.S_ISVTX
+	}
+	// No mapping for Go's ModeTemporary (plan9 only).
+	return
+}