Adding upstream version 2.5.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

index/upsidedown/index_reader.go

@@ -0,0 +1,228 @@
+//  Copyright (c) 2014 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 upsidedown
+
+import (
+	"context"
+	"reflect"
+
+	"github.com/blevesearch/bleve/v2/document"
+	index "github.com/blevesearch/bleve_index_api"
+	store "github.com/blevesearch/upsidedown_store_api"
+)
+
+var reflectStaticSizeIndexReader int
+
+func init() {
+	var ir IndexReader
+	reflectStaticSizeIndexReader = int(reflect.TypeOf(ir).Size())
+}
+
+type IndexReader struct {
+	index    *UpsideDownCouch
+	kvreader store.KVReader
+	docCount uint64
+}
+
+func (i *IndexReader) TermFieldReader(ctx context.Context, term []byte, fieldName string, includeFreq, includeNorm, includeTermVectors bool) (index.TermFieldReader, error) {
+	fieldIndex, fieldExists := i.index.fieldCache.FieldNamed(fieldName, false)
+	if fieldExists {
+		return newUpsideDownCouchTermFieldReader(i, term, uint16(fieldIndex), includeFreq, includeNorm, includeTermVectors)
+	}
+	return newUpsideDownCouchTermFieldReader(i, []byte{ByteSeparator}, ^uint16(0), includeFreq, includeNorm, includeTermVectors)
+}
+
+func (i *IndexReader) FieldDict(fieldName string) (index.FieldDict, error) {
+	return i.FieldDictRange(fieldName, nil, nil)
+}
+
+func (i *IndexReader) FieldDictRange(fieldName string, startTerm []byte, endTerm []byte) (index.FieldDict, error) {
+	fieldIndex, fieldExists := i.index.fieldCache.FieldNamed(fieldName, false)
+	if fieldExists {
+		return newUpsideDownCouchFieldDict(i, uint16(fieldIndex), startTerm, endTerm)
+	}
+	return newUpsideDownCouchFieldDict(i, ^uint16(0), []byte{ByteSeparator}, []byte{})
+}
+
+func (i *IndexReader) FieldDictPrefix(fieldName string, termPrefix []byte) (index.FieldDict, error) {
+	return i.FieldDictRange(fieldName, termPrefix, termPrefix)
+}
+
+func (i *IndexReader) DocIDReaderAll() (index.DocIDReader, error) {
+	return newUpsideDownCouchDocIDReader(i)
+}
+
+func (i *IndexReader) DocIDReaderOnly(ids []string) (index.DocIDReader, error) {
+	return newUpsideDownCouchDocIDReaderOnly(i, ids)
+}
+
+func (i *IndexReader) Document(id string) (doc index.Document, err error) {
+	// first hit the back index to confirm doc exists
+	var backIndexRow *BackIndexRow
+	backIndexRow, err = backIndexRowForDoc(i.kvreader, []byte(id))
+	if err != nil {
+		return
+	}
+	if backIndexRow == nil {
+		return
+	}
+	rvd := document.NewDocument(id)
+	storedRow := NewStoredRow([]byte(id), 0, []uint64{}, 'x', nil)
+	storedRowScanPrefix := storedRow.ScanPrefixForDoc()
+	it := i.kvreader.PrefixIterator(storedRowScanPrefix)
+	defer func() {
+		if cerr := it.Close(); err == nil && cerr != nil {
+			err = cerr
+		}
+	}()
+	key, val, valid := it.Current()
+	for valid {
+		safeVal := make([]byte, len(val))
+		copy(safeVal, val)
+		var row *StoredRow
+		row, err = NewStoredRowKV(key, safeVal)
+		if err != nil {
+			return nil, err
+		}
+		if row != nil {
+			fieldName := i.index.fieldCache.FieldIndexed(row.field)
+			field := decodeFieldType(row.typ, fieldName, row.arrayPositions, row.value)
+			if field != nil {
+				rvd.AddField(field)
+			}
+		}
+
+		it.Next()
+		key, val, valid = it.Current()
+	}
+	return rvd, nil
+}
+
+func (i *IndexReader) documentVisitFieldTerms(id index.IndexInternalID, fields []string, visitor index.DocValueVisitor) error {
+	fieldsMap := make(map[uint16]string, len(fields))
+	for _, f := range fields {
+		id, ok := i.index.fieldCache.FieldNamed(f, false)
+		if ok {
+			fieldsMap[id] = f
+		}
+	}
+
+	tempRow := BackIndexRow{
+		doc: id,
+	}
+
+	keyBuf := GetRowBuffer()
+	if tempRow.KeySize() > len(keyBuf.buf) {
+		keyBuf.buf = make([]byte, 2*tempRow.KeySize())
+	}
+	defer PutRowBuffer(keyBuf)
+	keySize, err := tempRow.KeyTo(keyBuf.buf)
+	if err != nil {
+		return err
+	}
+
+	value, err := i.kvreader.Get(keyBuf.buf[:keySize])
+	if err != nil {
+		return err
+	}
+	if value == nil {
+		return nil
+	}
+
+	return visitBackIndexRow(value, func(field uint32, term []byte) {
+		if field, ok := fieldsMap[uint16(field)]; ok {
+			visitor(field, term)
+		}
+	})
+}
+
+func (i *IndexReader) Fields() (fields []string, err error) {
+	fields = make([]string, 0)
+	it := i.kvreader.PrefixIterator([]byte{'f'})
+	defer func() {
+		if cerr := it.Close(); err == nil && cerr != nil {
+			err = cerr
+		}
+	}()
+	key, val, valid := it.Current()
+	for valid {
+		var row UpsideDownCouchRow
+		row, err = ParseFromKeyValue(key, val)
+		if err != nil {
+			fields = nil
+			return
+		}
+		if row != nil {
+			fieldRow, ok := row.(*FieldRow)
+			if ok {
+				fields = append(fields, fieldRow.name)
+			}
+		}
+
+		it.Next()
+		key, val, valid = it.Current()
+	}
+	return
+}
+
+func (i *IndexReader) GetInternal(key []byte) ([]byte, error) {
+	internalRow := NewInternalRow(key, nil)
+	return i.kvreader.Get(internalRow.Key())
+}
+
+func (i *IndexReader) DocCount() (uint64, error) {
+	return i.docCount, nil
+}
+
+func (i *IndexReader) Close() error {
+	return i.kvreader.Close()
+}
+
+func (i *IndexReader) ExternalID(id index.IndexInternalID) (string, error) {
+	return string(id), nil
+}
+
+func (i *IndexReader) InternalID(id string) (index.IndexInternalID, error) {
+	return index.IndexInternalID(id), nil
+}
+
+func incrementBytes(in []byte) []byte {
+	rv := make([]byte, len(in))
+	copy(rv, in)
+	for i := len(rv) - 1; i >= 0; i-- {
+		rv[i] = rv[i] + 1
+		if rv[i] != 0 {
+			// didn't overflow, so stop
+			break
+		}
+	}
+	return rv
+}
+
+func (i *IndexReader) DocValueReader(fields []string) (index.DocValueReader, error) {
+	return &DocValueReader{i: i, fields: fields}, nil
+}
+
+type DocValueReader struct {
+	i      *IndexReader
+	fields []string
+}
+
+func (dvr *DocValueReader) VisitDocValues(id index.IndexInternalID,
+	visitor index.DocValueVisitor) error {
+	return dvr.i.documentVisitFieldTerms(id, dvr.fields, visitor)
+}
+
+func (dvr *DocValueReader) BytesRead() uint64 { return 0 }