| 347 | } |
| 348 | |
| 349 | func removeFileIfIsNotSQLite(filename string) (err error) { |
| 350 | var ( |
| 351 | f *os.File |
| 352 | fileHeader [6]byte |
| 353 | ) |
| 354 | if f, err = os.Open(filename); err != nil && os.IsNotExist(err) { |
| 355 | // file not exists |
| 356 | err = nil |
| 357 | return |
| 358 | } else if err != nil { |
| 359 | // may be no read permission |
| 360 | return |
| 361 | } |
| 362 | |
| 363 | if _, err = f.Read(fileHeader[:]); err != nil && errors.Cause(err) != io.EOF { |
| 364 | // read file failed |
| 365 | _ = f.Close() |
| 366 | return |
| 367 | } |
| 368 | |
| 369 | if string(fileHeader[:]) == "SQLite" { |
| 370 | // valid sqlite file |
| 371 | err = nil |
| 372 | _ = f.Close() |
| 373 | return |
| 374 | } |
| 375 | |
| 376 | _ = f.Close() |
| 377 | |
| 378 | // backup and remove file |
| 379 | bakFile := filename + ".bak" |
| 380 | if _, err = os.Stat(bakFile); err != nil && os.IsNotExist(err) { |
| 381 | err = nil |
| 382 | _ = os.Rename(filename, filename+".bak") |
| 383 | } else { |
| 384 | _ = os.Remove(filename) |
| 385 | } |
| 386 | |
| 387 | return |
| 388 | } |