forked from hsg4ok/mqtt
/
util.go
79 lines (69 loc) · 1.49 KB
/
util.go
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package mqtt
import (
"io"
"bytes"
"errors"
)
func bool2byte(b bool) byte {
if b {
return 1
}
return 0
}
func byte2bool(x byte) bool {
if (x & 1) == 1 {
return true
}
return false
}
func readRemainingBytes(r *bytes.Reader) (buf []byte, err error) {
buf, err = readBytes(r.Len(), r)
return
}
func writeBytes(b []byte, w io.Writer) (err error) {
n, err := w.Write(b)
if err != nil {
return
}
if len(b) != n {
err = errors.New("Unable to write bytes")
return
}
return
}
func writeByte(b byte, w io.Writer) error {
return writeBytes([]byte{b}, w)
}
// Big-Endian style ... MSB, LSB
func writeUint16(x uint16, w io.Writer) error {
return writeBytes([]byte{ byte(x >> 8), byte(x & 0xff) }, w)
}
func readBytes(n int, r io.Reader) (result []byte, err error) {
result = make([]byte, n)
actual, err := io.ReadFull(r, result)
if err != nil {
return
}
if actual < n {
err = errors.New("Expected to read more bytes")
return
}
return
}
func readByte(r io.Reader) (result byte, err error) {
bytes_buf, err := readBytes(1, r)
if err != nil {
return
}
result = byte(bytes_buf[0])
return
}
// Big-Endian style ... MSB, LSB
func readUint16(r io.Reader) (result uint16, err error) {
bytes_buf, err := readBytes(2, r)
if err != nil {
return
}
result = uint16(bytes_buf[0]) << 8 | uint16(bytes_buf[1])
return
}