cleanly separate version handling

This commit is contained in:
AJ ONeal 2020-05-04 22:12:48 -06:00
parent bdb8c87a30
commit 5b8941ed37
1 changed files with 54 additions and 49 deletions

View File

@ -46,63 +46,68 @@ func splitHeader(header []byte, names []string) (map[string]string, error) {
return result, nil return result, nil
} }
//ReadMessage - // ReadMessage checks the protocol and switches accordingly
func ReadMessage(b []byte) (*Packer, error) { func ReadMessage(b []byte) (*Packer, error) {
// Detect protocol in use // Detect protocol in use
if b[0] == packerV1 { if b[0] == packerV1 {
// Separate the header and body using the header length in the second byte. return ReadV1Message(b)
p := NewPacker(nil)
header := b[2 : b[1]+2]
data := b[b[1]+2:]
// Handle the different parts of the header.
parts, err := splitHeader(header, []string{"address family", "address", "port", "data length", "service"})
if err != nil {
return nil, err
}
if familyText := parts["address family"]; familyText == addressFamilyText[FamilyIPv4] {
p.Header.family = FamilyIPv4
} else if familyText == addressFamilyText[FamilyIPv6] {
p.Header.family = FamilyIPv6
} else {
return nil, fmt.Errorf("Address family %q not supported", familyText)
}
p.Header.address = net.ParseIP(parts["address"])
if p.Header.address == nil {
return nil, fmt.Errorf("Invalid network address %q", parts["address"])
} else if p.Header.family == FamilyIPv4 && p.Header.address.To4() == nil {
return nil, fmt.Errorf("Address %q is not in address family %s", parts["address"], p.Header.Family())
}
//handle port
if port, err := strconv.Atoi(parts["port"]); err != nil {
return nil, fmt.Errorf("Error converting port %q: %v", parts["port"], err)
} else if port <= 0 || port > 65535 {
return nil, fmt.Errorf("Port %d out of range", port)
} else {
p.Header.port = port
}
//handle data length
if dataLen, err := strconv.Atoi(parts["data length"]); err != nil {
return nil, fmt.Errorf("Error converting data length %q: %v", parts["data length"], err)
} else if dataLen != len(data) {
return nil, fmt.Errorf("Data length %d doesn't match received length %d", dataLen, len(data))
}
//handle Service
p.Header.service = parts["service"]
//handle payload
p.Data.AppendBytes(data)
return p, nil
} }
return nil, fmt.Errorf("Version %d not supported", 255-b[0]) return nil, fmt.Errorf("Version %d not supported", 255-b[0])
} }
// ReadV1Message parses a v1-formatted message
func ReadV1Message(b []byte) (*Packer, error) {
// Separate the header and body using the header length in the second byte.
p := NewPacker(nil)
header := b[2 : b[1]+2]
data := b[b[1]+2:]
// Handle the different parts of the header.
parts, err := splitHeader(header, []string{"address family", "address", "port", "data length", "service"})
if err != nil {
return nil, err
}
if familyText := parts["address family"]; familyText == addressFamilyText[FamilyIPv4] {
p.Header.family = FamilyIPv4
} else if familyText == addressFamilyText[FamilyIPv6] {
p.Header.family = FamilyIPv6
} else {
return nil, fmt.Errorf("Address family %q not supported", familyText)
}
p.Header.address = net.ParseIP(parts["address"])
if p.Header.address == nil {
return nil, fmt.Errorf("Invalid network address %q", parts["address"])
} else if p.Header.family == FamilyIPv4 && p.Header.address.To4() == nil {
return nil, fmt.Errorf("Address %q is not in address family %s", parts["address"], p.Header.Family())
}
//handle port
if port, err := strconv.Atoi(parts["port"]); err != nil {
return nil, fmt.Errorf("Error converting port %q: %v", parts["port"], err)
} else if port <= 0 || port > 65535 {
return nil, fmt.Errorf("Port %d out of range", port)
} else {
p.Header.port = port
}
//handle data length
if dataLen, err := strconv.Atoi(parts["data length"]); err != nil {
return nil, fmt.Errorf("Error converting data length %q: %v", parts["data length"], err)
} else if dataLen != len(data) {
return nil, fmt.Errorf("Data length %d doesn't match received length %d", dataLen, len(data))
}
//handle Service
p.Header.service = parts["service"]
//handle payload
p.Data.AppendBytes(data)
return p, nil
}
//PackV1 -- Outputs version 1 of packer //PackV1 -- Outputs version 1 of packer
func (p *Packer) PackV1() bytes.Buffer { func (p *Packer) PackV1() bytes.Buffer {
header := strings.Join([]string{ header := strings.Join([]string{