More protocols

protocol/meshcore/util.go

@@ -0,0 +1,84 @@
+package meshcore
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"strings"
+	"time"
+
+	"git.maze.io/go/ham/protocol/meshcore/crypto"
+)
+
+type Position struct {
+	Latitude  float64
+	Longitude float64
+}
+
+func (pos *Position) String() string {
+	if pos == nil {
+		return "<unknown>"
+	}
+	return fmt.Sprintf("%f,%f", pos.Latitude, pos.Longitude)
+}
+
+func (pos *Position) Marshal() []byte {
+	var buf [8]byte
+	binary.LittleEndian.PutUint32(buf[0:], uint32(pos.Latitude*1e6))
+	binary.LittleEndian.PutUint32(buf[4:], uint32(pos.Longitude*1e6))
+	return buf[:]
+}
+
+func (pos *Position) Unmarshal(b []byte) error {
+	if len(b) < 8 {
+		return io.ErrUnexpectedEOF
+	}
+	pos.Latitude = float64(binary.LittleEndian.Uint32(b[0:])) / 1e6
+	pos.Longitude = float64(binary.LittleEndian.Uint32(b[4:])) / 1e6
+	return nil
+}
+
+func encodeTime(b []byte, t time.Time) {
+	binary.LittleEndian.PutUint32(b, uint32(t.Unix()))
+}
+
+func decodeTime(b []byte) time.Time {
+	return time.Unix(int64(binary.LittleEndian.Uint32(b)), 0).UTC()
+}
+
+func encodeFrequency(b []byte, f float64) {
+	binary.LittleEndian.PutUint32(b, uint32(f*1e3))
+}
+
+func decodeFrequency(b []byte) float64 {
+	return float64(int64(binary.LittleEndian.Uint32(b))) / 1e3
+}
+
+func decodeCString(b []byte) string {
+	if i := bytes.IndexByte(b, 0x00); i > -1 {
+		return string(b[:i])
+	}
+	return string(b)
+}
+
+func formatPath(path []byte) string {
+	p := make([]string, len(path))
+	for i, node := range path {
+		p[i] = fmt.Sprintf("%02X", node)
+	}
+	return strings.Join(p, ">")
+}
+
+func formatPublicKey(b []byte) string {
+	switch len(b) {
+	case 8:
+		return fmt.Sprintf("<%016x>", b)
+	case crypto.PublicKeySize:
+		return fmt.Sprintf("<%06x…%06x>", b[:3], b[29:])
+	case crypto.PrivateKeySize:
+		return formatPublicKey(b[32:])
+	default:
+		return "<unknown>"
+	}
+}