Class: Lobster::Network::Packet

Inherits:
Object
  • Object
show all
Defined in:
lib/lobster/network/packet.rb

Overview

Self-contained network data. Packets can carry a maximum payload of 64 KB.

Constant Summary collapse

HEADER_SIZE =

Number of bytes in the header of all packets.

2
MAX_PAYLOAD_SIZE =

Number of bytes that a packet can hold in its payload.

2 ** (HEADER_SIZE * 8)

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(payload) ⇒ Packet

Creates a new packet.

Parameters:

  • payload (String) —

    Bytes for the packet's payload.



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# File 'lib/lobster/network/packet.rb', line 20

def initialize(payload)
  fail ArgumentError unless payload.is_a?(String)
  fail ArgumentError if payload.bytesize > MAX_PAYLOAD_SIZE

  @payload = payload.dup
  @payload.freeze
end

Instance Attribute Details

#payload ⇒ String (readonly)

Retrieves the raw payload data contained in the packet.

Returns:

  • (String) —

    Raw payload byte string.



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# File 'lib/lobster/network/packet.rb', line 16

def payload
  @payload
end

Class Method Details

.read(input) ⇒ Packet

Reads a packet from an input stream.

Parameters:

  • input (IO) —

    Input source to read a packet from.

Returns:

  • (Packet) —

    Packet read from the input stream.



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# File 'lib/lobster/network/packet.rb', line 37

def self.read(input)
  payload_size = read_header(input)
  payload      = read_payload(input, payload_size)
  Packet.new(payload)
end

Instance Method Details

#size ⇒ Fixnum

Size of the packet's header and payload.

Returns:

  • (Fixnum) —

    Size in bytes.



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# File 'lib/lobster/network/packet.rb', line 30

def size
  @payload.bytesize + HEADER_SIZE
end

#write(output) ⇒ nil

Writes the packet to an output stream.

Parameters:

  • output (IO) —

    Output destination to write the packet to.

Returns:

  • (nil) 


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# File 'lib/lobster/network/packet.rb', line 65

def write(output)
  write_header(output)
  write_payload(output)
  nil
end