// Verify attempts to find any structural errors in DB wrt the organization of
// it as defined by lldb.Allocator. Any problems found are reported to 'log'
// except non verify related errors like disk read fails etc. If 'log' returns
// false or the error doesn't allow to (reliably) continue, the verification
// process is stopped and an error is returned from the Verify function.
// Passing a nil log works like providing a log function always returning
// false. Any non-structural errors, like for instance Filer read errors, are
// NOT reported to 'log', but returned as the Verify's return value, because
// Verify cannot proceed in such cases. Verify returns nil only if it fully
// completed verifying DB without detecting any error.
//
// It is recommended to limit the number reported problems by returning false
// from 'log' after reaching some limit. Huge and corrupted DB can produce an
// overwhelming error report dataset.
//
// The verifying process will scan the whole DB at least 3 times (a trade
// between processing space and time consumed). It doesn't read the content of
// free blocks above the head/tail info bytes. If the 3rd phase detects lost
// free space, then a 4th scan (a faster one) is performed to precisely report
// all of them.
//
// Statistics are returned via 'stats' if non nil. The statistics are valid
// only if Verify succeeded, ie. it didn't reported anything to log and it
// returned a nil error.
func (db *DB) Verify(log func(error) bool, stats *lldb.AllocStats) (err error) {
bitmapf, err := fileutil.TempFile(".", "verifier", ".tmp")
if err != nil {
return
}
defer func() {
tn := bitmapf.Name()
bitmapf.Close()
os.Remove(tn)
}()
bitmap := lldb.NewSimpleFileFiler(bitmapf)
if err = db.enter(); err != nil {
return
}
defer func() {
if e := recover(); e != nil {
err = fmt.Errorf("%v", e)
}
db.leave(&err)
}()
return db.alloc.Verify(bitmap, log, stats)
}
// CreateTemp creates a new temporary DB in the directory dir with a basename
// beginning with prefix and name ending in suffix. If dir is the empty string,
// CreateTemp uses the default directory for temporary files (see os.TempDir).
// Multiple programs calling CreateTemp simultaneously will not choose the same
// file name for the DB. The caller can use Name() to find the pathname of the
// DB file. It is the caller's responsibility to remove the file when no longer
// needed.
//
// For the meaning of opts please see documentation of Options.
func CreateTemp(dir, prefix, suffix string, opts *Options) (db *DB, err error) {
f, err := fileutil.TempFile(dir, prefix, suffix)
if err != nil {
return
}
return create(f, lldb.NewSimpleFileFiler(f), opts, false)
}