FilePath: tt.fields.FilePath,
}
if got := fh.Payload(); !reflect.DeepEqual(got, tt.want) {
- t.Errorf("Payload() = %v, want %v", got, tt.want)
+ t.Errorf("Read() = %v, want %v", got, tt.want)
}
})
}
package hotline
import (
- "bytes"
+ "bufio"
"encoding/binary"
- "errors"
"fmt"
"github.com/jhalter/mobius/concat"
"net"
"time"
)
+// TrackerRegistration represents the payload a Hotline server sends to a Tracker to register
type TrackerRegistration struct {
Port [2]byte // Server listening port number
UserCount int // Number of users connected to this particular server
Description string // Description of the server
}
-func (tr *TrackerRegistration) Payload() []byte {
+// TODO: reimplement as io.Reader
+func (tr *TrackerRegistration) Read() []byte {
userCount := make([]byte, 2)
binary.BigEndian.PutUint16(userCount, uint16(tr.UserCount))
return err
}
- if _, err := conn.Write(tr.Payload()); err != nil {
+ b := tr.Read()
+
+ if _, err := conn.Write(b); err != nil {
return err
}
return nil, err
}
- totalRead := 0
-
- buf := make([]byte, 4096)
- var readLen int
- if readLen, err = conn.Read(buf); err != nil {
- return nil, err
- }
- totalRead += readLen // 1514
-
var th TrackerHeader
- if err := binary.Read(bytes.NewReader(buf[:6]), binary.BigEndian, &th); err != nil {
+ if err := binary.Read(conn, binary.BigEndian, &th); err != nil {
return nil, err
}
var info ServerInfoHeader
- if err := binary.Read(bytes.NewReader(buf[6:14]), binary.BigEndian, &info); err != nil {
+ if err := binary.Read(conn, binary.BigEndian, &info); err != nil {
return nil, err
}
- payloadSize := int(binary.BigEndian.Uint16(info.MsgDataSize[:]))
-
- buf = buf[:readLen]
- if totalRead < payloadSize {
- for {
- tmpBuf := make([]byte, 4096)
- if readLen, err = conn.Read(tmpBuf); err != nil {
- return nil, err
- }
- buf = append(buf, tmpBuf[:readLen]...)
- totalRead += readLen
- if totalRead >= payloadSize {
- break
- }
- }
- }
totalSrv := int(binary.BigEndian.Uint16(info.SrvCount[:]))
- srvBuf := buf[14:totalRead]
+ scanner := bufio.NewScanner(conn)
+ scanner.Split(serverScanner)
var servers []ServerRecord
-
for {
+ scanner.Scan()
var srv ServerRecord
- n, _ := srv.Read(srvBuf)
- servers = append(servers, srv)
-
- srvBuf = srvBuf[n:]
+ _, _ = srv.Read(scanner.Bytes())
+ servers = append(servers, srv)
if len(servers) == totalSrv {
- return servers, nil
+ break
}
+ }
- if len(srvBuf) == 0 {
- return servers, errors.New("tracker sent too few bytes for server count")
- }
+ return servers, nil
+}
+
+// serverScanner implements bufio.SplitFunc for parsing the tracker list into ServerRecords tokens
+// Example payload:
+// 00000000 18 05 30 63 15 7c 00 02 00 00 10 54 68 65 20 4d |..0c.|.....The M|
+// 00000010 6f 62 69 75 73 20 53 74 72 69 70 40 48 6f 6d 65 |obius Strip@Home|
+// 00000020 20 6f 66 20 74 68 65 20 4d 6f 62 69 75 73 20 48 | of the Mobius H|
+// 00000030 6f 74 6c 69 6e 65 20 73 65 72 76 65 72 20 61 6e |otline server an|
+// 00000040 64 20 63 6c 69 65 6e 74 20 7c 20 54 52 54 50 48 |d client | TRTPH|
+// 00000050 4f 54 4c 2e 63 6f 6d 3a 35 35 30 30 2d 4f 3a b2 |OTL.com:5500-O:.|
+// 00000060 15 7c 00 00 00 00 08 53 65 6e 65 63 74 75 73 20 |.|.....Senectus |
+func serverScanner(data []byte, _ bool) (advance int, token []byte, err error) {
+ if len(data) < 10 {
+ return 0, nil, nil
}
+
+ // A server entry has two variable length fields: the name and description.
+ // To get the token length, we first need the name length from the 10th byte:
+ nameLen := int(data[10])
+
+ // Next we need the description length from the 11+nameLen byte:
+ descLen := int(data[11+nameLen])
+
+ return 12 + nameLen + descLen, data[0 : 12+nameLen+descLen], nil
}
+// Read implements io.Reader for ServerRecord
func (s *ServerRecord) Read(b []byte) (n int, err error) {
copy(s.IPAddr[:], b[0:4])
copy(s.Port[:], b[4:6])
return 12 + nameLen + int(s.DescriptionSize), nil
}
-func (s *ServerRecord) PortInt() int {
- data := binary.BigEndian.Uint16(s.Port[:])
- return int(data)
-}
-
func (s *ServerRecord) Addr() string {
return fmt.Sprintf("%s:%s",
net.IP(s.IPAddr[:]),
package hotline
import (
+ "fmt"
+ "github.com/stretchr/testify/assert"
"reflect"
"testing"
)
Name: tt.fields.Name,
Description: tt.fields.Description,
}
- if got := tr.Payload(); !reflect.DeepEqual(got, tt.want) {
- t.Errorf("Payload() = %v, want %v", got, tt.want)
+ if got := tr.Read(); !reflect.DeepEqual(got, tt.want) {
+ t.Errorf("Read() = %v, want %v", got, tt.want)
}
})
}
}
+
+func Test_serverScanner(t *testing.T) {
+ type args struct {
+ data []byte
+ atEOF bool
+ }
+ tests := []struct {
+ name string
+ args args
+ wantAdvance int
+ wantToken []byte
+ wantErr assert.ErrorAssertionFunc
+ }{
+ {
+ name: "when a full server entry is provided",
+ args: args{
+ data: []byte{
+ 0x18, 0x05, 0x30, 0x63, // IP Addr
+ 0x15, 0x7c, // Port
+ 0x00, 0x02, // UserCount
+ 0x00, 0x00, // ??
+ 0x03, // Name Len
+ 0x54, 0x68, 0x65, // Name
+ 0x03, // Desc Len
+ 0x54, 0x54, 0x54, // Description
+ },
+ atEOF: false,
+ },
+ wantAdvance: 18,
+ wantToken: []byte{
+ 0x18, 0x05, 0x30, 0x63, // IP Addr
+ 0x15, 0x7c, // Port
+ 0x00, 0x02, // UserCount
+ 0x00, 0x00, // ??
+ 0x03, // Name Len
+ 0x54, 0x68, 0x65, // Name
+ 0x03, // Desc Len
+ 0x54, 0x54, 0x54, // Description
+ },
+ wantErr: assert.NoError,
+ },
+ {
+ name: "when extra bytes are provided",
+ args: args{
+ data: []byte{
+ 0x18, 0x05, 0x30, 0x63, // IP Addr
+ 0x15, 0x7c, // Port
+ 0x00, 0x02, // UserCount
+ 0x00, 0x00, // ??
+ 0x03, // Name Len
+ 0x54, 0x68, 0x65, // Name
+ 0x03, // Desc Len
+ 0x54, 0x54, 0x54, // Description
+ 0x54, 0x54, 0x54, 0x54, 0x54, 0x54, 0x54, 0x54, 0x54,
+ },
+ atEOF: false,
+ },
+ wantAdvance: 18,
+ wantToken: []byte{
+ 0x18, 0x05, 0x30, 0x63, // IP Addr
+ 0x15, 0x7c, // Port
+ 0x00, 0x02, // UserCount
+ 0x00, 0x00, // ??
+ 0x03, // Name Len
+ 0x54, 0x68, 0x65, // Name
+ 0x03, // Desc Len
+ 0x54, 0x54, 0x54, // Description
+ },
+ wantErr: assert.NoError,
+ },
+ {
+ name: "when insufficient bytes are provided",
+ args: args{
+ data: []byte{
+ 0, 0,
+ },
+ atEOF: false,
+ },
+ wantAdvance: 0,
+ wantToken: []byte(nil),
+ wantErr: assert.NoError,
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ gotAdvance, gotToken, err := serverScanner(tt.args.data, tt.args.atEOF)
+ if !tt.wantErr(t, err, fmt.Sprintf("serverScanner(%v, %v)", tt.args.data, tt.args.atEOF)) {
+ return
+ }
+ assert.Equalf(t, tt.wantAdvance, gotAdvance, "serverScanner(%v, %v)", tt.args.data, tt.args.atEOF)
+ assert.Equalf(t, tt.wantToken, gotToken, "serverScanner(%v, %v)", tt.args.data, tt.args.atEOF)
+ })
+ }
+}