// Copyright (C) 2014 The Protocol Authors.
package protocol
import (
"context"
"crypto/sha256"
"encoding/binary"
"fmt"
"io"
"path"
"strings"
"sync"
"time"
lz4 "github.com/bkaradzic/go-lz4"
"github.com/pkg/errors"
)
const (
// Shifts
KiB = 10
MiB = 20
GiB = 30
)
const (
// MaxMessageLen is the largest message size allowed on the wire. (500 MB)
MaxMessageLen = 500 * 1000 * 1000
// MinBlockSize is the minimum block size allowed
MinBlockSize = 128 << KiB
// MaxBlockSize is the maximum block size allowed
MaxBlockSize = 16 << MiB
// DesiredPerFileBlocks is the number of blocks we aim for per file
DesiredPerFileBlocks = 2000
)
// BlockSizes is the list of valid block sizes, from min to max
var BlockSizes []int
// For each block size, the hash of a block of all zeroes
var sha256OfEmptyBlock = map[int][sha256.Size]byte{
128 << KiB: {0xfa, 0x43, 0x23, 0x9b, 0xce, 0xe7, 0xb9, 0x7c, 0xa6, 0x2f, 0x0, 0x7c, 0xc6, 0x84, 0x87, 0x56, 0xa, 0x39, 0xe1, 0x9f, 0x74, 0xf3, 0xdd, 0xe7, 0x48, 0x6d, 0xb3, 0xf9, 0x8d, 0xf8, 0xe4, 0x71},
256 << KiB: {0x8a, 0x39, 0xd2, 0xab, 0xd3, 0x99, 0x9a, 0xb7, 0x3c, 0x34, 0xdb, 0x24, 0x76, 0x84, 0x9c, 0xdd, 0xf3, 0x3, 0xce, 0x38, 0x9b, 0x35, 0x82, 0x68, 0x50, 0xf9, 0xa7, 0x0, 0x58, 0x9b, 0x4a, 0x90},
512 << KiB: {0x7, 0x85, 0x4d, 0x2f, 0xef, 0x29, 0x7a, 0x6, 0xba, 0x81, 0x68, 0x5e, 0x66, 0xc, 0x33, 0x2d, 0xe3, 0x6d, 0x5d, 0x18, 0xd5, 0x46, 0x92, 0x7d, 0x30, 0xda, 0xad, 0x6d, 0x7f, 0xda, 0x15, 0x41},
1 << MiB: {0x30, 0xe1, 0x49, 0x55, 0xeb, 0xf1, 0x35, 0x22, 0x66, 0xdc, 0x2f, 0xf8, 0x6, 0x7e, 0x68, 0x10, 0x46, 0x7, 0xe7, 0x50, 0xab, 0xb9, 0xd3, 0xb3, 0x65, 0x82, 0xb8, 0xaf, 0x90, 0x9f, 0xcb, 0x58},
2 << MiB: {0x56, 0x47, 0xf0, 0x5e, 0xc1, 0x89, 0x58, 0x94, 0x7d, 0x32, 0x87, 0x4e, 0xeb, 0x78, 0x8f, 0xa3, 0x96, 0xa0, 0x5d, 0xb, 0xab, 0x7c, 0x1b, 0x71, 0xf1, 0x12, 0xce, 0xb7, 0xe9, 0xb3, 0x1e, 0xee},
4 << MiB: {0xbb, 0x9f, 0x8d, 0xf6, 0x14, 0x74, 0xd2, 0x5e, 0x71, 0xfa, 0x0, 0x72, 0x23, 0x18, 0xcd, 0x38, 0x73, 0x96, 0xca, 0x17,