1 files changed, 25 insertions, 0 deletions
diff --git a/whisper/sort.go b/whisper/sort.go
new file mode 100644
index 000000000..8c5b46e9e
--- /dev/null
+++ b/whisper/sort.go
@@ -0,0 +1,25 @@
+package whisper
+
+import "sort"
+
+type sortedKeys struct {
+	k []int32
+}
+
+func (self *sortedKeys) Len() int           { return len(self.k) }
+func (self *sortedKeys) Less(i, j int) bool { return self.k[i] < self.k[j] }
+func (self *sortedKeys) Swap(i, j int)      { self.k[i], self.k[j] = self.k[j], self.k[i] }
+
+func sortKeys(m map[int32]Hash) []int32 {
+	sorted := new(sortedKeys)
+	sorted.k = make([]int32, len(m))
+	i := 0
+	for key, _ := range m {
+		sorted.k[i] = key
+		i++
+	}
+
+	sort.Sort(sorted)
+
+	return sorted.k
+}