module EventMachine::WebSocket::Framing03
Constants
- DATA_FRAMES
Frames are either data frames or control frames
- FRAME_TYPES
- FRAME_TYPES_INVERSE
Public Instance Methods
initialize_framing()
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# File lib/em-websocket/framing03.rb, line 5 def initialize_framing @data = '' @application_data_buffer = '' # Used for MORE frames @frame_type = nil end
process_data()
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# File lib/em-websocket/framing03.rb, line 11 def process_data error = false while !error && @data.size > 1 pointer = 0 more = ((@data.getbyte(pointer) & 0b10000000) == 0b10000000) ^ fin # Ignoring rsv1-3 for now opcode = @data.getbyte(0) & 0b00001111 pointer += 1 # Ignoring rsv4 length = @data.getbyte(pointer) & 0b01111111 pointer += 1 payload_length = case length when 127 # Length defined by 8 bytes # Check buffer size if @data.getbyte(pointer+8-1) == nil debug [:buffer_incomplete, @data] error = true next end # Only using the last 4 bytes for now, till I work out how to # unpack 8 bytes. I'm sure 4GB frames will do for now :) l = @data[(pointer+4)..(pointer+7)].unpack('N').first pointer += 8 l when 126 # Length defined by 2 bytes # Check buffer size if @data.getbyte(pointer+2-1) == nil debug [:buffer_incomplete, @data] error = true next end l = @data[pointer..(pointer+1)].unpack('n').first pointer += 2 l else length end if payload_length > @connection.max_frame_size raise WSMessageTooBigError, "Frame length too long (#{payload_length} bytes)" end # Check buffer size if @data.getbyte(pointer+payload_length-1) == nil debug [:buffer_incomplete, @data] error = true next end # Throw away data up to pointer @data.slice!(0...pointer) # Read application data application_data = @data.slice!(0...payload_length) frame_type = opcode_to_type(opcode) if frame_type == :continuation && !@frame_type raise WSProtocolError, 'Continuation frame not expected' end if more debug [:moreframe, frame_type, application_data] @application_data_buffer << application_data # The message type is passed in the first frame @frame_type ||= frame_type else # Message is complete if frame_type == :continuation @application_data_buffer << application_data message(@frame_type, '', @application_data_buffer) @application_data_buffer = '' @frame_type = nil else message(frame_type, '', application_data) end end end # end while end
send_frame(frame_type, application_data)
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# File lib/em-websocket/framing03.rb, line 97 def send_frame(frame_type, application_data) debug [:sending_frame, frame_type, application_data] if @state == :closing && data_frame?(frame_type) raise WebSocketError, "Cannot send data frame since connection is closing" end frame = '' opcode = type_to_opcode(frame_type) byte1 = opcode # since more, rsv1-3 are 0 frame << byte1 length = application_data.size if length <= 125 byte2 = length # since rsv4 is 0 frame << byte2 elsif length < 65536 # write 2 byte length frame << 126 frame << [length].pack('n') else # write 8 byte length frame << 127 frame << [length >> 32, length & 0xFFFFFFFF].pack("NN") end frame << application_data @connection.send_data(frame) end
send_text_frame(data)
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# File lib/em-websocket/framing03.rb, line 127 def send_text_frame(data) send_frame(:text, data) end
Private Instance Methods
data_frame?(type)
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# File lib/em-websocket/framing03.rb, line 156 def data_frame?(type) DATA_FRAMES.include?(type) end
fin()
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This allows flipping the more bit to fin for draft 04
# File lib/em-websocket/framing03.rb, line 134 def fin; false; end
opcode_to_type(opcode)
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# File lib/em-websocket/framing03.rb, line 152 def opcode_to_type(opcode) FRAME_TYPES_INVERSE[opcode] || raise(WSProtocolError, "Unknown opcode #{opcode}") end
type_to_opcode(frame_type)
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# File lib/em-websocket/framing03.rb, line 148 def type_to_opcode(frame_type) FRAME_TYPES[frame_type] || raise("Unknown frame type") end