Class: Protocol::MQTT::Codec::Reader

Inherits:
Object
  • Object
show all
Defined in:
lib/protocol/mqtt/codec.rb

Overview

Cursor reader over a byte string.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(bytes) ⇒ Reader

Returns a new instance of Reader.



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# File 'lib/protocol/mqtt/codec.rb', line 17

def initialize(bytes)
  @bytes = bytes.b
  @pos = 0
end

Instance Attribute Details

#pos ⇒ Object (readonly)

Returns the value of attribute pos.



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# File 'lib/protocol/mqtt/codec.rb', line 14

def pos
  @pos
end

Instance Method Details

#eof? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/protocol/mqtt/codec.rb', line 28

def eof?
  @pos >= @bytes.bytesize
end

#read(n) ⇒ Object

Raises:



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# File 'lib/protocol/mqtt/codec.rb', line 33

def read(n)
  raise MalformedPacket, "truncated body: need #{n}, have #{remaining}" if remaining < n
  chunk = @bytes.byteslice(@pos, n)
  @pos += n
  chunk
end

#read_binary ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 67

def read_binary
  len = read_u16
  read(len)
end

#read_rest ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 78

def read_rest
  read(remaining)
end

#read_string_pair ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 73

def read_string_pair
  [read_utf8, read_utf8]
end

#read_u16 ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 46

def read_u16
  read(2).unpack1("n")
end

#read_u32 ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 51

def read_u32
  read(4).unpack1("N")
end

#read_u8 ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 41

def read_u8
  read(1).unpack1("C")
end

#read_utf8 ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 61

def read_utf8
  len = read_u16
  read(len).force_encoding(Encoding::UTF_8)
end

#read_vbi ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 56

def read_vbi
  VBI.decode(self)
end

#remaining ⇒ Object 



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# File 'lib/protocol/mqtt/codec.rb', line 23

def remaining
  @bytes.bytesize - @pos
end