Adding upstream version 1.22.1.upstream/1.22.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/src/hash/crc32/example_test.go b/src/hash/crc32/example_test.go
new file mode 100644
index 0000000..621bf83
--- /dev/null
+++ b/src/hash/crc32/example_test.go
@@ -0,0 +1,28 @@
+// Copyright 2015 The Go 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 crc32_test
+
+import (
+	"fmt"
+	"hash/crc32"
+)
+
+func ExampleMakeTable() {
+	// In this package, the CRC polynomial is represented in reversed notation,
+	// or LSB-first representation.
+	//
+	// LSB-first representation is a hexadecimal number with n bits, in which the
+	// most significant bit represents the coefficient of x⁰ and the least significant
+	// bit represents the coefficient of xⁿ⁻¹ (the coefficient for xⁿ is implicit).
+	//
+	// For example, CRC32-Q, as defined by the following polynomial,
+	//	x³²+ x³¹+ x²⁴+ x²²+ x¹⁶+ x¹⁴+ x⁸+ x⁷+ x⁵+ x³+ x¹+ x⁰
+	// has the reversed notation 0b11010101100000101000001010000001, so the value
+	// that should be passed to MakeTable is 0xD5828281.
+	crc32q := crc32.MakeTable(0xD5828281)
+	fmt.Printf("%08x\n", crc32.Checksum([]byte("Hello world"), crc32q))
+	// Output:
+	// 2964d064
+}