diff options
Diffstat (limited to 'Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go')
| -rw-r--r-- | Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go | 73 |
1 files changed, 50 insertions, 23 deletions
diff --git a/Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go b/Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go index ae61bece9..c5be420b3 100644 --- a/Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go +++ b/Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/table/reader.go @@ -26,12 +26,15 @@ import ( "github.com/syndtr/goleveldb/leveldb/util" ) +// Reader errors. var ( ErrNotFound = errors.ErrNotFound ErrReaderReleased = errors.New("leveldb/table: reader released") ErrIterReleased = errors.New("leveldb/table: iterator released") ) +// ErrCorrupted describes error due to corruption. This error will be wrapped +// with errors.ErrCorrupted. type ErrCorrupted struct { Pos int64 Size int64 @@ -61,7 +64,7 @@ type block struct { func (b *block) seek(cmp comparer.Comparer, rstart, rlimit int, key []byte) (index, offset int, err error) { index = sort.Search(b.restartsLen-rstart-(b.restartsLen-rlimit), func(i int) bool { offset := int(binary.LittleEndian.Uint32(b.data[b.restartsOffset+4*(rstart+i):])) - offset += 1 // shared always zero, since this is a restart point + offset++ // shared always zero, since this is a restart point v1, n1 := binary.Uvarint(b.data[offset:]) // key length _, n2 := binary.Uvarint(b.data[offset+n1:]) // value length m := offset + n1 + n2 @@ -356,7 +359,7 @@ func (i *blockIter) Prev() bool { i.value = nil offset := i.block.restartOffset(ri) if offset == i.offset { - ri -= 1 + ri-- if ri < 0 { i.dir = dirSOI return false @@ -783,8 +786,8 @@ func (r *Reader) getDataIterErr(dataBH blockHandle, slice *util.Range, verifyChe // table. And a nil Range.Limit is treated as a key after all keys in // the table. // -// The returned iterator is not goroutine-safe and should be released -// when not used. +// The returned iterator is not safe for concurrent use and should be released +// after use. // // Also read Iterator documentation of the leveldb/iterator package. func (r *Reader) NewIterator(slice *util.Range, ro *opt.ReadOptions) iterator.Iterator { @@ -826,18 +829,21 @@ func (r *Reader) find(key []byte, filtered bool, ro *opt.ReadOptions, noValue bo index := r.newBlockIter(indexBlock, nil, nil, true) defer index.Release() + if !index.Seek(key) { - err = index.Error() - if err == nil { + if err = index.Error(); err == nil { err = ErrNotFound } return } + dataBH, n := decodeBlockHandle(index.Value()) if n == 0 { r.err = r.newErrCorruptedBH(r.indexBH, "bad data block handle") - return + return nil, nil, r.err } + + // The filter should only used for exact match. if filtered && r.filter != nil { filterBlock, frel, ferr := r.getFilterBlock(true) if ferr == nil { @@ -847,30 +853,53 @@ func (r *Reader) find(key []byte, filtered bool, ro *opt.ReadOptions, noValue bo } frel.Release() } else if !errors.IsCorrupted(ferr) { - err = ferr - return + return nil, nil, ferr } } + data := r.getDataIter(dataBH, nil, r.verifyChecksum, !ro.GetDontFillCache()) - defer data.Release() if !data.Seek(key) { - err = data.Error() - if err == nil { - err = ErrNotFound + data.Release() + if err = data.Error(); err != nil { + return + } + + // The nearest greater-than key is the first key of the next block. + if !index.Next() { + if err = index.Error(); err == nil { + err = ErrNotFound + } + return + } + + dataBH, n = decodeBlockHandle(index.Value()) + if n == 0 { + r.err = r.newErrCorruptedBH(r.indexBH, "bad data block handle") + return nil, nil, r.err + } + + data = r.getDataIter(dataBH, nil, r.verifyChecksum, !ro.GetDontFillCache()) + if !data.Next() { + data.Release() + if err = data.Error(); err == nil { + err = ErrNotFound + } + return } - return } - // Don't use block buffer, no need to copy the buffer. + + // Key doesn't use block buffer, no need to copy the buffer. rkey = data.Key() if !noValue { if r.bpool == nil { value = data.Value() } else { - // Use block buffer, and since the buffer will be recycled, the buffer - // need to be copied. + // Value does use block buffer, and since the buffer will be + // recycled, it need to be copied. value = append([]byte{}, data.Value()...) } } + data.Release() return } @@ -888,7 +917,7 @@ func (r *Reader) Find(key []byte, filtered bool, ro *opt.ReadOptions) (rkey, val return r.find(key, filtered, ro, false) } -// Find finds key that is greater than or equal to the given key. +// FindKey finds key that is greater than or equal to the given key. // It returns ErrNotFound if the table doesn't contain such key. // If filtered is true then the nearest 'block' will be checked against // 'filter data' (if present) and will immediately return ErrNotFound if @@ -987,7 +1016,7 @@ func (r *Reader) Release() { // NewReader creates a new initialized table reader for the file. // The fi, cache and bpool is optional and can be nil. // -// The returned table reader instance is goroutine-safe. +// The returned table reader instance is safe for concurrent use. func NewReader(f io.ReaderAt, size int64, fd storage.FileDesc, cache *cache.NamespaceGetter, bpool *util.BufferPool, o *opt.Options) (*Reader, error) { if f == nil { return nil, errors.New("leveldb/table: nil file") @@ -1039,9 +1068,8 @@ func NewReader(f io.ReaderAt, size int64, fd storage.FileDesc, cache *cache.Name if errors.IsCorrupted(err) { r.err = err return r, nil - } else { - return nil, err } + return nil, err } // Set data end. @@ -1086,9 +1114,8 @@ func NewReader(f io.ReaderAt, size int64, fd storage.FileDesc, cache *cache.Name if errors.IsCorrupted(err) { r.err = err return r, nil - } else { - return nil, err } + return nil, err } if r.filter != nil { r.filterBlock, err = r.readFilterBlock(r.filterBH) |