1 files changed, 263 insertions, 0 deletions
diff --git a/vendor/github.com/blevesearch/zap/v13/dict.go b/vendor/github.com/blevesearch/zap/v13/dict.go
new file mode 100644
index 0000000000..ad4a8f8dc5
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v13/dict.go
@@ -0,0 +1,263 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/couchbase/vellum"
+)
+
+// Dictionary is the zap representation of the term dictionary
+type Dictionary struct {
+	sb        *SegmentBase
+	field     string
+	fieldID   uint16
+	fst       *vellum.FST
+	fstReader *vellum.Reader
+}
+
+// PostingsList returns the postings list for the specified term
+func (d *Dictionary) PostingsList(term []byte, except *roaring.Bitmap,
+	prealloc segment.PostingsList) (segment.PostingsList, error) {
+	var preallocPL *PostingsList
+	pl, ok := prealloc.(*PostingsList)
+	if ok && pl != nil {
+		preallocPL = pl
+	}
+	return d.postingsList(term, except, preallocPL)
+}
+
+func (d *Dictionary) postingsList(term []byte, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
+	if d.fstReader == nil {
+		if rv == nil || rv == emptyPostingsList {
+			return emptyPostingsList, nil
+		}
+		return d.postingsListInit(rv, except), nil
+	}
+
+	postingsOffset, exists, err := d.fstReader.Get(term)
+	if err != nil {
+		return nil, fmt.Errorf("vellum err: %v", err)
+	}
+	if !exists {
+		if rv == nil || rv == emptyPostingsList {
+			return emptyPostingsList, nil
+		}
+		return d.postingsListInit(rv, except), nil
+	}
+
+	return d.postingsListFromOffset(postingsOffset, except, rv)
+}
+
+func (d *Dictionary) postingsListFromOffset(postingsOffset uint64, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
+	rv = d.postingsListInit(rv, except)
+
+	err := rv.read(postingsOffset, d)
+	if err != nil {
+		return nil, err
+	}
+
+	return rv, nil
+}
+
+func (d *Dictionary) postingsListInit(rv *PostingsList, except *roaring.Bitmap) *PostingsList {
+	if rv == nil || rv == emptyPostingsList {
+		rv = &PostingsList{}
+	} else {
+		postings := rv.postings
+		if postings != nil {
+			postings.Clear()
+		}
+
+		*rv = PostingsList{} // clear the struct
+
+		rv.postings = postings
+	}
+	rv.sb = d.sb
+	rv.except = except
+	return rv
+}
+
+func (d *Dictionary) Contains(key []byte) (bool, error) {
+	return d.fst.Contains(key)
+}
+
+// Iterator returns an iterator for this dictionary
+func (d *Dictionary) Iterator() segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator(nil, nil)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// PrefixIterator returns an iterator which only visits terms having the
+// the specified prefix
+func (d *Dictionary) PrefixIterator(prefix string) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	kBeg := []byte(prefix)
+	kEnd := segment.IncrementBytes(kBeg)
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator(kBeg, kEnd)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// RangeIterator returns an iterator which only visits terms between the
+// start and end terms.  NOTE: bleve.index API specifies the end is inclusive.
+func (d *Dictionary) RangeIterator(start, end string) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	// need to increment the end position to be inclusive
+	var endBytes []byte
+	if len(end) > 0 {
+		endBytes = []byte(end)
+		if endBytes[len(endBytes)-1] < 0xff {
+			endBytes[len(endBytes)-1]++
+		} else {
+			endBytes = append(endBytes, 0xff)
+		}
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator([]byte(start), endBytes)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// AutomatonIterator returns an iterator which only visits terms
+// having the the vellum automaton and start/end key range
+func (d *Dictionary) AutomatonIterator(a vellum.Automaton,
+	startKeyInclusive, endKeyExclusive []byte) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Search(a, startKeyInclusive, endKeyExclusive)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+func (d *Dictionary) OnlyIterator(onlyTerms [][]byte,
+	includeCount bool) segment.DictionaryIterator {
+
+	rv := &DictionaryIterator{
+		d:         d,
+		omitCount: !includeCount,
+	}
+
+	var buf bytes.Buffer
+	builder, err := vellum.New(&buf, nil)
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+	for _, term := range onlyTerms {
+		err = builder.Insert(term, 0)
+		if err != nil {
+			rv.err = err
+			return rv
+		}
+	}
+	err = builder.Close()
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+
+	onlyFST, err := vellum.Load(buf.Bytes())
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+
+	itr, err := d.fst.Search(onlyFST, nil, nil)
+	if err == nil {
+		rv.itr = itr
+	} else if err != vellum.ErrIteratorDone {
+		rv.err = err
+	}
+
+	return rv
+}
+
+// DictionaryIterator is an iterator for term dictionary
+type DictionaryIterator struct {
+	d         *Dictionary
+	itr       vellum.Iterator
+	err       error
+	tmp       PostingsList
+	entry     index.DictEntry
+	omitCount bool
+}
+
+// Next returns the next entry in the dictionary
+func (i *DictionaryIterator) Next() (*index.DictEntry, error) {
+	if i.err != nil && i.err != vellum.ErrIteratorDone {
+		return nil, i.err
+	} else if i.itr == nil || i.err == vellum.ErrIteratorDone {
+		return nil, nil
+	}
+	term, postingsOffset := i.itr.Current()
+	i.entry.Term = string(term)
+	if !i.omitCount {
+		i.err = i.tmp.read(postingsOffset, i.d)
+		if i.err != nil {
+			return nil, i.err
+		}
+		i.entry.Count = i.tmp.Count()
+	}
+	i.err = i.itr.Next()
+	return &i.entry, nil
+}