initial commit

vendor/github.com/blevesearch/bleve/index/firestorm/util.go

@@ -0,0 +1,99 @@
+//  Copyright (c) 2015 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 firestorm
+
+import (
+	"io/ioutil"
+	"log"
+
+	"github.com/blevesearch/bleve/index/store"
+)
+
+type KVVisitor func(key, val []byte) (bool, error)
+
+func visitPrefix(reader store.KVReader, prefix []byte, visitor KVVisitor) (err error) {
+	start := prefix
+	if start == nil {
+		start = []byte{}
+	}
+	it := reader.PrefixIterator(start)
+	defer func() {
+		if cerr := it.Close(); err == nil && cerr != nil {
+			err = cerr
+		}
+	}()
+	k, v, valid := it.Current()
+	for valid {
+		var cont bool
+		cont, err = visitor(k, v)
+		if err != nil {
+			// visitor encountered an error, stop and return it
+			return
+		}
+		if !cont {
+			// vistor has requested we stop iteration, return nil
+			return
+		}
+		it.Next()
+		k, v, valid = it.Current()
+	}
+	return
+}
+
+func visitRange(reader store.KVReader, start, end []byte, visitor KVVisitor) (err error) {
+	it := reader.RangeIterator(start, end)
+	defer func() {
+		if cerr := it.Close(); err == nil && cerr != nil {
+			err = cerr
+		}
+	}()
+	k, v, valid := it.Current()
+	for valid {
+		var cont bool
+		cont, err = visitor(k, v)
+		if err != nil {
+			// visitor encountered an error, stop and return it
+			return
+		}
+		if !cont {
+			// vistor has requested we stop iteration, return nil
+			return
+		}
+		it.Next()
+		k, v, valid = it.Current()
+	}
+	return
+}
+
+type DocNumberList []uint64
+
+func (l DocNumberList) Len() int           { return len(l) }
+func (l DocNumberList) Less(i, j int) bool { return l[i] > l[j] }
+func (l DocNumberList) Swap(i, j int)      { l[i], l[j] = l[j], l[i] }
+
+// HighestValid returns the highest valid doc number
+// from a *SORTED* DocNumberList
+// if no doc number in the list is valid, then 0
+func (l DocNumberList) HighestValid(maxRead uint64) uint64 {
+	for _, dn := range l {
+		if dn <= maxRead {
+			return dn
+		}
+	}
+	return 0
+}
+
+var logger = log.New(ioutil.Discard, "bleve.index.firestorm ", 0)
+
+// SetLog sets the logger used for logging
+// by default log messages are sent to ioutil.Discard
+func SetLog(l *log.Logger) {
+	logger = l
+}