Restructure codebase move crypto, checksum to top-level, move `split` into donut, move crypto/keys into api/auth

pkg/hash/crc32c/crc32c_linux.go

@@ -0,0 +1,89 @@
+// Copyright 2009 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.
+// Golang project:
+//    https://github.com/golang/go/blob/master/LICENSE
+
+// Using this part of Minio codebase under the license
+// Apache License Version 2.0 with modifications
+
+// Package crc32 implements the 32-bit cyclic redundancy check, or CRC-32,
+// checksum. See http://en.wikipedia.org/wiki/Cyclic_redundancy_check for
+// information.
+
+package crc32c
+
+import (
+	"hash"
+	"io"
+)
+
+// The size of a CRC-32 checksum in bytes.
+const Size = 4
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	crc uint32
+}
+
+// New creates a new hash.Hash32 computing the CRC-32 checksum
+// using the polynomial represented by the Table.
+func New() hash.Hash32 {
+	return &digest{crc: 0}
+}
+
+// Return size of crc
+func (d *digest) Size() int { return Size }
+
+// Stub
+func (d *digest) BlockSize() int { return 1 }
+
+// Get crc in bytes
+func (d *digest) Sum(in []byte) []byte {
+	s := d.crc
+	return append(in, byte(s>>24), byte(s>>16), byte(s>>8), byte(s))
+}
+
+// Sum32 - return current crc in digest object
+func (d *digest) Sum32() uint32 { return d.crc }
+
+// Reset default crc
+func (d *digest) Reset() { d.crc = 0 }
+
+// Update returns the result of adding the bytes in p to the crc.
+func (d *digest) update(crc uint32, p []byte) uint32 {
+	return updateCastanagoliPCL(crc, p)
+}
+
+// Write data
+func (d *digest) Write(p []byte) (n int, err error) {
+	d.crc = d.update(d.crc, p)
+	return len(p), nil
+}
+
+/// Convenience functions
+
+// Sum32 - single caller crc helper
+func Sum32(data []byte) uint32 {
+	crc32 := New()
+	crc32.Reset()
+	crc32.Write(data)
+	return crc32.Sum32()
+}
+
+// Sum - low memory footprint io.Reader based crc helper
+func Sum(reader io.Reader) (uint32, error) {
+	h := New()
+	var err error
+	for err == nil {
+		length := 0
+		byteBuffer := make([]byte, 1024*1024)
+		length, err = reader.Read(byteBuffer)
+		byteBuffer = byteBuffer[0:length]
+		h.Write(byteBuffer)
+	}
+	if err != io.EOF {
+		return 0, err
+	}
+	return h.Sum32(), nil
+}