func handleGet(filename string, address string) error {
serverAddr, conn, err := getAddrAndConn(address)
if err != nil {
return err
}
defer conn.Close()
rrq := common.RequestPacket{
OpCode: common.OpRRQ,
Filename: filename,
Mode: "octet",
}
_, err = conn.WriteTo(rrq.ToBytes(), serverAddr)
if err != nil {
return fmt.Errorf("Error sending RRQ packet: %v", err)
}
f, err := os.Create(filename)
if err != nil {
return fmt.Errorf("Error creating file: %v", err)
}
defer f.Close()
bw := bufio.NewWriter(f)
defer bw.Flush()
var n int
tid := uint16(1)
packet := make([]byte, common.MaxPacketSize)
for {
// Always use the serverAddr returned as it changes after the first packet.
n, serverAddr, err = common.WriteFile(bw, conn, serverAddr, packet, tid)
if err != nil {
return err
}
if n < 4+common.BlockSize {
break
}
tid++
}
return nil
}
// handle reading a local file and sending it to the server
func handlePut(filename, address string) error {
f, err := os.Open(filename)
if err != nil {
return fmt.Errorf("Error opening file: %v", err)
}
defer f.Close()
br := bufio.NewReader(f)
serverAddr, conn, err := getAddrAndConn(address)
if err != nil {
return err
}
defer conn.Close()
// Send WRQ packet
wrq := common.RequestPacket{
OpCode: common.OpWRQ,
Filename: filename,
Mode: "octet",
}
_, err = conn.WriteTo(wrq.ToBytes(), serverAddr)
if err != nil {
return fmt.Errorf("Error sending WRQ packet: %v", err)
}
// Get the ACK
ackBuf := make([]byte, 4)
_, remoteAddr, err := conn.ReadFrom(ackBuf)
if err != nil {
return fmt.Errorf("Error reading ACK packet: %v", err)
}
_, err = common.ParseAckPacket(ackBuf)
if err != nil {
return fmt.Errorf("Error parsing ACK packet: %v", err)
}
common.ReadFileLoop(br, conn, remoteAddr, common.BlockSize)
return nil
}