From a031b83a09a8628435317a03f199cdc18b78262f Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Wed, 1 Nov 2017 11:24:59 -0400 Subject: Initial checkin from CRI-O repo Signed-off-by: Matthew Heon --- .../github.com/hpcloud/tail/watch/filechanges.go | 36 +++ vendor/github.com/hpcloud/tail/watch/inotify.go | 128 ++++++++++ .../hpcloud/tail/watch/inotify_tracker.go | 260 +++++++++++++++++++++ vendor/github.com/hpcloud/tail/watch/polling.go | 118 ++++++++++ vendor/github.com/hpcloud/tail/watch/watch.go | 20 ++ 5 files changed, 562 insertions(+) create mode 100644 vendor/github.com/hpcloud/tail/watch/filechanges.go create mode 100644 vendor/github.com/hpcloud/tail/watch/inotify.go create mode 100644 vendor/github.com/hpcloud/tail/watch/inotify_tracker.go create mode 100644 vendor/github.com/hpcloud/tail/watch/polling.go create mode 100644 vendor/github.com/hpcloud/tail/watch/watch.go (limited to 'vendor/github.com/hpcloud/tail/watch') 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) +} -- cgit v1.2.3-54-g00ecf