impl/memory: Implement Queries

impl/memory/gkvlite_iter.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package memory
 
 import (
         "bytes"
         "sync"
 
@@ skipping 48 matching lines @@
 }
 
 func multiIterate(defs []*iterDefinition, cb func(suffix []byte) bool) {
         ts := make([]*iterator, len(defs))
         prefixLens := make([]int, len(defs))
         for i, def := range defs {
                 if def.prefix == nil {
                         panic("got nil prefix")
                 }
 
-                end := []byte(nil)
-                if def.end != nil {
-                        end = bjoin(def.prefix, def.end)
-                } else {
-                        end = []byte(increment(string(def.prefix), true))
-                }
-
+                // start at the prefix, plus any defined start suffix
                 start := def.prefix
                 if def.start != nil {
                         start = bjoin(def.prefix, def.start)
                 }
 
+                // end at the prefix+1 (if there was a defined prefix), plus any defined
+                // start suffix.
+                end := []byte(nil)
+                if def.end != nil {
+                        end = bjoin(def.prefix, def.end)
+                } else if def.prefix != nil {
+                        end = increment(def.prefix)
+                }
+
                 ts[i] = newIterator(def.c, start, end)
                 prefixLens[i] = len(def.prefix)
                 defer ts[i].stop()
         }
 
         suffix := []byte(nil)
         skip := -1
 
         for {
                 stop := false
@@ skipping 129 matching lines @@
         t.ch <- &cmd{targ, func(i *gkvlite.Item) {
                 defer close(waiter)
 
                 cb(i)
                 if i == nil {
                         t.stop()
                 }
         }}
         <-waiter
 }