Files
quic-go/internal/utils/utils.go
Marten Seemann beadeb9da7 use sort.Slice to sort the tags in the handshake message
sort.Slice was added in Go 1.8. Now that we've dropped support for Go
1.7, we can make use of it.
2017-08-02 12:00:52 +07:00

130 lines
3.0 KiB
Go

package utils
import (
"bytes"
"io"
)
// ReadUintN reads N bytes
func ReadUintN(b io.ByteReader, length uint8) (uint64, error) {
var res uint64
for i := uint8(0); i < length; i++ {
bt, err := b.ReadByte()
if err != nil {
return 0, err
}
res ^= uint64(bt) << (i * 8)
}
return res, nil
}
// ReadUint64 reads a uint64
func ReadUint64(b io.ByteReader) (uint64, error) {
var b1, b2, b3, b4, b5, b6, b7, b8 uint8
var err error
if b1, err = b.ReadByte(); err != nil {
return 0, err
}
if b2, err = b.ReadByte(); err != nil {
return 0, err
}
if b3, err = b.ReadByte(); err != nil {
return 0, err
}
if b4, err = b.ReadByte(); err != nil {
return 0, err
}
if b5, err = b.ReadByte(); err != nil {
return 0, err
}
if b6, err = b.ReadByte(); err != nil {
return 0, err
}
if b7, err = b.ReadByte(); err != nil {
return 0, err
}
if b8, err = b.ReadByte(); err != nil {
return 0, err
}
return uint64(b1) + uint64(b2)<<8 + uint64(b3)<<16 + uint64(b4)<<24 + uint64(b5)<<32 + uint64(b6)<<40 + uint64(b7)<<48 + uint64(b8)<<56, nil
}
// ReadUint32 reads a uint32
func ReadUint32(b io.ByteReader) (uint32, error) {
var b1, b2, b3, b4 uint8
var err error
if b1, err = b.ReadByte(); err != nil {
return 0, err
}
if b2, err = b.ReadByte(); err != nil {
return 0, err
}
if b3, err = b.ReadByte(); err != nil {
return 0, err
}
if b4, err = b.ReadByte(); err != nil {
return 0, err
}
return uint32(b1) + uint32(b2)<<8 + uint32(b3)<<16 + uint32(b4)<<24, nil
}
// ReadUint16 reads a uint16
func ReadUint16(b io.ByteReader) (uint16, error) {
var b1, b2 uint8
var err error
if b1, err = b.ReadByte(); err != nil {
return 0, err
}
if b2, err = b.ReadByte(); err != nil {
return 0, err
}
return uint16(b1) + uint16(b2)<<8, nil
}
// WriteUint64 writes a uint64
func WriteUint64(b *bytes.Buffer, i uint64) {
b.Write([]byte{
uint8(i), uint8(i >> 8), uint8(i >> 16), uint8(i >> 24),
uint8(i >> 32), uint8(i >> 40), uint8(i >> 48), uint8(i >> 56),
})
}
// WriteUint56 writes 56 bit of a uint64
func WriteUint56(b *bytes.Buffer, i uint64) {
b.Write([]byte{
uint8(i), uint8(i >> 8), uint8(i >> 16), uint8(i >> 24),
uint8(i >> 32), uint8(i >> 40), uint8(i >> 48),
})
}
// WriteUint48 writes 48 bit of a uint64
func WriteUint48(b *bytes.Buffer, i uint64) {
b.Write([]byte{
uint8(i), uint8(i >> 8), uint8(i >> 16), uint8(i >> 24),
uint8(i >> 32), uint8(i >> 40),
})
}
// WriteUint40 writes 40 bit of a uint64
func WriteUint40(b *bytes.Buffer, i uint64) {
b.Write([]byte{
uint8(i), uint8(i >> 8), uint8(i >> 16),
uint8(i >> 24), uint8(i >> 32),
})
}
// WriteUint32 writes a uint32
func WriteUint32(b *bytes.Buffer, i uint32) {
b.Write([]byte{uint8(i), uint8(i >> 8), uint8(i >> 16), uint8(i >> 24)})
}
// WriteUint24 writes 24 bit of a uint32
func WriteUint24(b *bytes.Buffer, i uint32) {
b.Write([]byte{uint8(i), uint8(i >> 8), uint8(i >> 16)})
}
// WriteUint16 writes a uint16
func WriteUint16(b *bytes.Buffer, i uint16) {
b.Write([]byte{uint8(i), uint8(i >> 8)})
}