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.
()
| 336 | // moved or truncated. When moved or deleted - the file will be |
| 337 | // reopened if ReOpen is true. Truncated files are always reopened. |
| 338 | func (tail *Tail) waitForChanges() error { |
| 339 | if tail.changes == nil { |
| 340 | pos, err := tail.file.Seek(0, os.SEEK_CUR) |
| 341 | if err != nil { |
| 342 | return err |
| 343 | } |
| 344 | tail.changes, err = tail.watcher.ChangeEvents(&tail.Tomb, pos) |
| 345 | if err != nil { |
| 346 | return err |
| 347 | } |
| 348 | } |
| 349 | |
| 350 | select { |
| 351 | case <-tail.changes.Modified: |
| 352 | return nil |
| 353 | case <-tail.changes.Deleted: |
| 354 | tail.changes = nil |
| 355 | if tail.ReOpen { |
| 356 | // XXX: we must not log from a library. |
| 357 | tail.Logger.Printf("Re-opening moved/deleted file %s ...", tail.Filename) |
| 358 | if err := tail.reopen(); err != nil { |
| 359 | return err |
| 360 | } |
| 361 | tail.Logger.Printf("Successfully reopened %s", tail.Filename) |
| 362 | tail.openReader() |
| 363 | return nil |
| 364 | } else { |
| 365 | tail.Logger.Printf("Stopping tail as file no longer exists: %s", tail.Filename) |
| 366 | return ErrStop |
| 367 | } |
| 368 | case <-tail.changes.Truncated: |
| 369 | // Always reopen truncated files (Follow is true) |
| 370 | tail.Logger.Printf("Re-opening truncated file %s ...", tail.Filename) |
| 371 | if err := tail.reopen(); err != nil { |
| 372 | return err |
| 373 | } |
| 374 | tail.Logger.Printf("Successfully reopened truncated %s", tail.Filename) |
| 375 | tail.openReader() |
| 376 | return nil |
| 377 | case <-tail.Dying(): |
| 378 | return ErrStop |
| 379 | } |
| 380 | panic("unreachable") |
| 381 | } |
| 382 | |
| 383 | func (tail *Tail) openReader() { |
| 384 | if tail.MaxLineSize > 0 { |
no test coverage detected