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Diffstat (limited to 'vendor/github.com/hpcloud/tail/tail.go')
-rw-r--r--vendor/github.com/hpcloud/tail/tail.go438
1 files changed, 0 insertions, 438 deletions
diff --git a/vendor/github.com/hpcloud/tail/tail.go b/vendor/github.com/hpcloud/tail/tail.go
deleted file mode 100644
index 2d252d605..000000000
--- a/vendor/github.com/hpcloud/tail/tail.go
+++ /dev/null
@@ -1,438 +0,0 @@
-// 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)
-}
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-11-17 08:32:57 +0000