// Copyright 2021 The Gitea Authors. All rights reserved.// SPDX-License-Identifier: MIT package packages import (	"io" 	"forgejo.org/modules/util/filebuffer") // HashedSizeReader provide methods to read, sum hashes and a Size methodtype HashedSizeReader interface {	io.Reader	HashSummer	Size() int64} // HashedBuffer is buffer which calculates multiple checksumstype HashedBuffer struct {	*filebuffer.FileBackedBuffer 	hash *MultiHasher 	combinedWriter io.Writer} const DefaultMemorySize = 32 * 1024 * 1024 // NewHashedBuffer creates a hashed buffer with the default memory sizefunc NewHashedBuffer() (*HashedBuffer, error) {	return NewHashedBufferWithSize(DefaultMemorySize)} // NewHashedBufferWithSize creates a hashed buffer with a specific memory sizefunc NewHashedBufferWithSize(maxMemorySize int) (*HashedBuffer, error) {	b, err := filebuffer.New(maxMemorySize)	if err != nil {		return nil, err	} 	hash := NewMultiHasher() 	combinedWriter := io.MultiWriter(b, hash) 	return &HashedBuffer{		b,		hash,		combinedWriter,	}, nil} // CreateHashedBufferFromReader creates a hashed buffer with the default memory size and copies the provided reader data into it.func CreateHashedBufferFromReader(r io.Reader) (*HashedBuffer, error) {	return CreateHashedBufferFromReaderWithSize(r, DefaultMemorySize)} // CreateHashedBufferFromReaderWithSize creates a hashed buffer and copies the provided reader data into it.func CreateHashedBufferFromReaderWithSize(r io.Reader, maxMemorySize int) (*HashedBuffer, error) {	b, err := NewHashedBufferWithSize(maxMemorySize)	if err != nil {		return nil, err	} 	_, err = io.Copy(b, r)	if err != nil {		return nil, err	} 	return b, nil} // Write implements io.Writerfunc (b *HashedBuffer) Write(p []byte) (int, error) {	return b.combinedWriter.Write(p)} // Sums gets the MD5, SHA1, SHA256, SHA512 and BLAKE2B checksums of the datafunc (b *HashedBuffer) Sums() (hashMD5, hashSHA1, hashSHA256, hashSHA512, hashBlake2b []byte) {	return b.hash.Sums()}