Add hash helpers

Author: richardwilkes

xmath/hashhelper/hashhelper.go

@@ -0,0 +1,69 @@
+// Copyright (c) 2024 by Richard A. Wilkes. All rights reserved.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, version 2.0. If a copy of the MPL was not distributed with
+// this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// This Source Code Form is "Incompatible With Secondary Licenses", as
+// defined by the Mozilla Public License, version 2.0.
+
+package hashhelper
+
+import (
+	"hash"
+)
+
+// String writes the given string to the hash.
+func String[T ~string](h hash.Hash, data T) {
+	Num64(h, len(data))
+	_, _ = h.Write([]byte(data))
+}
+
+// Num64 writes the given 64-bit number to the hash.
+func Num64[T ~int64 | ~uint64 | ~int | ~uint](h hash.Hash, data T) {
+	var buffer [8]byte
+	d := uint64(data)
+	buffer[0] = byte(d)
+	buffer[1] = byte(d >> 8)
+	buffer[2] = byte(d >> 16)
+	buffer[3] = byte(d >> 24)
+	buffer[4] = byte(d >> 32)
+	buffer[5] = byte(d >> 40)
+	buffer[6] = byte(d >> 48)
+	buffer[7] = byte(d >> 56)
+	_, _ = h.Write(buffer[:])
+}
+
+// Num32 writes the given 32-bit number to the hash.
+func Num32[T ~int32 | ~uint32](h hash.Hash, data T) {
+	var buffer [4]byte
+	d := uint32(data)
+	buffer[0] = byte(d)
+	buffer[1] = byte(d >> 8)
+	buffer[2] = byte(d >> 16)
+	buffer[3] = byte(d >> 24)
+	_, _ = h.Write(buffer[:])
+}
+
+// Num16 writes the given 16-bit number to the hash.
+func Num16[T ~int16 | ~uint16](h hash.Hash, data T) {
+	var buffer [2]byte
+	d := uint16(data)
+	buffer[0] = byte(d)
+	buffer[1] = byte(d >> 8)
+	_, _ = h.Write(buffer[:])
+}
+
+// Num8 writes the given 8-bit number to the hash.
+func Num8[T ~uint8](h hash.Hash, data T) {
+	_, _ = h.Write([]byte{byte(data)})
+}
+
+// Bool writes the given boolean to the hash.
+func Bool[T ~bool](h hash.Hash, data T) {
+	var b byte
+	if data {
+		b = 1
+	}
+	_, _ = h.Write([]byte{b})
+}