Rename funnybase and add more serializations.

common/cmpbin/float.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 cmpbin
+
+import (
+        "encoding/binary"
+        "io"
+        "math"
+)
+
+// WriteFloat64 writes a memcmp-sortable float to buf. It returns the number
+// of bytes written (8, unless an error occurs), and any write error
+// encountered.
+func WriteFloat64(buf io.Writer, v float64) (n int, err error) {
+        bits := math.Float64bits(v)
+        bits = bits ^ (-(bits >> 63) | (1 << 63))
+        data := make([]byte, 8)
+        binary.BigEndian.PutUint64(data, bits)
+        return buf.Write(data)
+}
+
+// ReadFloat64 reads a memcmp-sortable float from buf (as written by
+// WriteFloat64). It also returns the number of bytes read (8, unless an error
+// occurs), and any read error encountered.
+func ReadFloat64(buf io.Reader) (ret float64, n int, err error) {
+        // byte-ordered floats http://stereopsis.com/radix.html
+        data := make([]byte, 8)
+        if n, err = buf.Read(data); err != nil {
+                return
+        }
+        bits := binary.BigEndian.Uint64(data)
+        ret = math.Float64frombits(bits ^ (((bits >> 63) - 1) | (1 << 63)))
+        return
+}