Module: E3DCMqtt::RSCP::DataType

Defined in:
lib/e3dc_mqtt/rscp/data_type.rb

Overview

RSCP value types. Each entry knows its byte representation, its fixed length (or nil for variable-length types), and how to pack/unpack a Ruby value.

Constant Summary collapse

NONE = 
0x00
BOOL = 
0x01
CHAR8 = 
0x02
UCHAR8 = 
0x03
INT16 = 
0x04
UINT16 = 
0x05
INT32 = 
0x06
UINT32 = 
0x07
INT64 = 
0x08
UINT64 = 
0x09
FLOAT32 = 
0x0A
DOUBLE64 = 
0x0B
BITFIELD = 
0x0C
CSTRING = 
0x0D
CONTAINER = 
0x0E
TIMESTAMP = 
0x0F
BYTEARRAY = 
0x10
ERROR = 
0xFF
NAMES = 
{
  NONE => :none, BOOL => :bool, CHAR8 => :char8, UCHAR8 => :uchar8,
  INT16 => :int16, UINT16 => :uint16, INT32 => :int32, UINT32 => :uint32,
  INT64 => :int64, UINT64 => :uint64, FLOAT32 => :float32, DOUBLE64 => :double64,
  BITFIELD => :bitfield, CSTRING => :cstring, CONTAINER => :container,
  TIMESTAMP => :timestamp, BYTEARRAY => :bytearray, ERROR => :error
}.freeze
FIXED_LENGTHS = 
{
  NONE => 0, BOOL => 1, CHAR8 => 1, UCHAR8 => 1,
  INT16 => 2, UINT16 => 2, INT32 => 4, UINT32 => 4,
  INT64 => 8, UINT64 => 8, FLOAT32 => 4, DOUBLE64 => 8,
  BITFIELD => 1, TIMESTAMP => 12, ERROR => 4
}.freeze
VARIABLE = 
Set.new([CSTRING, CONTAINER, BYTEARRAY]).freeze

Class Method Summary collapse

Class Method Details

.fixed_length(type) ⇒ Object 



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# File 'lib/e3dc_mqtt/rscp/data_type.rb', line 51

def fixed_length(type)
  FIXED_LENGTHS[type]
end

.name(type) ⇒ Object 



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# File 'lib/e3dc_mqtt/rscp/data_type.rb', line 47

def name(type)
  NAMES.fetch(type) { raise UnknownDataType, "unknown data type 0x%02x" % type }
end

.pack(type, value) ⇒ Object

Pack a Ruby value into its wire bytes. ‘value` semantics per type:

NONE          -> nil
BOOL          -> true/false
*INT* / *CHAR -> Integer
FLOAT/DOUBLE  -> Float
BITFIELD      -> Integer (0..255)
CSTRING       -> String (binary-safe UTF-8 bytes written)
BYTEARRAY     -> String (binary)
CONTAINER     -> Array<Message>      (caller handles recursion)
TIMESTAMP     -> Time
ERROR         -> Integer (uint32 error code)



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# File 'lib/e3dc_mqtt/rscp/data_type.rb', line 70

def pack(type, value)
  case type
  when NONE      then "".b
  when BOOL      then [value ? 1 : 0].pack("C")
  when CHAR8     then [value].pack("c")
  when UCHAR8    then [value].pack("C")
  when INT16     then [value].pack("s<")
  when UINT16    then [value].pack("S<")
  when INT32     then [value].pack("l<")
  when UINT32    then [value].pack("L<")
  when INT64     then [value].pack("q<")
  when UINT64    then [value].pack("Q<")
  when FLOAT32   then [value].pack("e")
  when DOUBLE64  then [value].pack("E")
  when BITFIELD  then [value].pack("C")
  when CSTRING   then value.to_s.b
  when BYTEARRAY then value.to_s.b
  when TIMESTAMP
    t = value.utc
    [t.to_i].pack("q<") + [(t.nsec)].pack("l<")
  when ERROR     then [value].pack("L<")
  when CONTAINER
    raise DataTypeMismatch, "CONTAINER must be packed by Message (recursive)"
  else
    raise UnknownDataType, "unknown data type 0x%02x" % type
  end
end

.unpack(type, bytes) ⇒ Object 



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# File 'lib/e3dc_mqtt/rscp/data_type.rb', line 98

def unpack(type, bytes)
  case type
  when NONE      then nil
  when BOOL      then bytes.unpack1("C") != 0
  when CHAR8     then bytes.unpack1("c")
  when UCHAR8    then bytes.unpack1("C")
  when INT16     then bytes.unpack1("s<")
  when UINT16    then bytes.unpack1("S<")
  when INT32     then bytes.unpack1("l<")
  when UINT32    then bytes.unpack1("L<")
  when INT64     then bytes.unpack1("q<")
  when UINT64    then bytes.unpack1("Q<")
  when FLOAT32   then bytes.unpack1("e")
  when DOUBLE64  then bytes.unpack1("E")
  when BITFIELD  then bytes.unpack1("C")
  when CSTRING
    s = bytes.dup
    s.force_encoding(Encoding::UTF_8)
    s.valid_encoding? ? s : bytes.dup.force_encoding(Encoding::BINARY)
  when BYTEARRAY then bytes.dup.force_encoding(Encoding::BINARY)
  when TIMESTAMP
    secs, nsec = bytes.unpack("q<l<")
    Time.at(secs, nsec, :nsec).utc
  when ERROR     then bytes.unpack1("L<")
  when CONTAINER
    raise DataTypeMismatch, "CONTAINER must be unpacked by Message (recursive)"
  else
    raise UnknownDataType, "unknown data type 0x%02x" % type
  end
end

.variable?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/e3dc_mqtt/rscp/data_type.rb', line 55

def variable?(type)
  VARIABLE.include?(type)
end