leveldb: internal comparer should simply returns nil if user comparer cannot shorten key
diff --git a/leveldb/comparer.go b/leveldb/comparer.go
index 248bf7c..448402b 100644
--- a/leveldb/comparer.go
+++ b/leveldb/comparer.go
@@ -6,7 +6,9 @@
package leveldb
-import "github.com/syndtr/goleveldb/leveldb/comparer"
+import (
+ "github.com/syndtr/goleveldb/leveldb/comparer"
+)
type iComparer struct {
ucmp comparer.Comparer
@@ -33,12 +35,12 @@
}
func (icmp *iComparer) Compare(a, b []byte) int {
- x := icmp.ucmp.Compare(internalKey(a).ukey(), internalKey(b).ukey())
+ x := icmp.uCompare(internalKey(a).ukey(), internalKey(b).ukey())
if x == 0 {
if m, n := internalKey(a).num(), internalKey(b).num(); m > n {
- x = -1
+ return -1
} else if m < n {
- x = 1
+ return 1
}
}
return x
@@ -46,30 +48,20 @@
func (icmp *iComparer) Separator(dst, a, b []byte) []byte {
ua, ub := internalKey(a).ukey(), internalKey(b).ukey()
- dst = icmp.ucmp.Separator(dst, ua, ub)
- if dst == nil {
- return nil
+ dst = icmp.uSeparator(dst, ua, ub)
+ if dst != nil && len(dst) < len(ua) && icmp.uCompare(ua, dst) < 0 {
+ // Append earliest possible number.
+ return append(dst, keyMaxNumBytes...)
}
- if len(dst) < len(ua) && icmp.uCompare(ua, dst) < 0 {
- dst = append(dst, keyMaxNumBytes...)
- } else {
- // Did not close possibilities that n maybe longer than len(ub).
- dst = append(dst, a[len(a)-8:]...)
- }
- return dst
+ return nil
}
func (icmp *iComparer) Successor(dst, b []byte) []byte {
ub := internalKey(b).ukey()
- dst = icmp.ucmp.Successor(dst, ub)
- if dst == nil {
- return nil
+ dst = icmp.uSuccessor(dst, ub)
+ if dst != nil && len(dst) < len(ub) && icmp.uCompare(ub, dst) < 0 {
+ // Append earliest possible number.
+ return append(dst, keyMaxNumBytes...)
}
- if len(dst) < len(ub) && icmp.uCompare(ub, dst) < 0 {
- dst = append(dst, keyMaxNumBytes...)
- } else {
- // Did not close possibilities that n maybe longer than len(ub).
- dst = append(dst, b[len(b)-8:]...)
- }
- return dst
+ return nil
}
