Class: FFI::MsgPack::Packer

Inherits:
Struct
  • Object
show all
Defined in:
lib/ffi/msgpack/packer.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ptr = nil) ⇒ Packer

Creates a new FFI::MsgPack::Packer.

Parameters:

  • ptr (FFI::Pointer) (defaults to: nil) —

    An optional pointer to an existing packer.

Since:

  • 0.2.0



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# File 'lib/ffi/msgpack/packer.rb', line 73

def initialize(ptr=nil)
  if ptr
    super(ptr)
  else
    super()
  end

  @object = MsgObject.new
end

Instance Attribute Details

#buffer ⇒ Object

The optional buffer to write packed Msg Objects into.



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# File 'lib/ffi/msgpack/packer.rb', line 12

def buffer
  @buffer
end

#total ⇒ Object

The total length of the buffer



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# File 'lib/ffi/msgpack/packer.rb', line 15

def total
  @total
end

Class Method Details

.create(buffer = nil) {|packed(,length)| ... } ⇒ Packer

Creates a new packer.

Parameters:

  • buffer (#<<) (defaults to: nil) —

    Optional buffer to append packed Msg Objects to.

Yields:

  • (packed(,length)) —

    If a block is given, it will be used as the callback to write the packed data.

Yield Parameters:

  • packed (String) —

    The packed bytes representing a Msg Object.

  • length (Integer) —

    The length of the packed data.

Returns:

  • (Packer) —

    The new packer.



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# File 'lib/ffi/msgpack/packer.rb', line 36

def Packer.create(buffer=nil,&block)
  packer = Packer.new()

  # zero the memory
  packer[:data] = nil
  packer[:callback] = nil

  # zero the total
  packer.total = 0

  if block
    # disable the buffer
    packer.buffer = nil

    # custom callback
    packer.callback(&block)
  else
    # set the buffer
    packer.buffer = (buffer || '')

    # setup the default callback
    packer.callback do |packed,length|
      packer.buffer << packed
    end
  end

  return packer
end

Instance Method Details

#<<(value) ⇒ Packer

Packs a Ruby object.

Parameters:

Returns:



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# File 'lib/ffi/msgpack/packer.rb', line 137

def <<(value)
  @object.set!(value)

  pack(@object)
  return self
end

#callback {|packed(,length)| ... } ⇒ Proc

Sets the write callback for the packer.

Yields:

  • (packed(,length)) —

    If a block is given, it will be used as the callback to write the packed data.

Yield Parameters:

  • packed (String) —

    The packed bytes representing a Msg Object.

  • length (Integer) —

    The length of the packed data.

Returns:

  • (Proc) —

    The new callback.



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# File 'lib/ffi/msgpack/packer.rb', line 99

def callback(&block)
  self[:callback] = Proc.new do |data_ptr,packed_buffer,length|
    @total += length

    packed = packed_buffer.read_bytes(length)

    if block.arity == 2
      block.call(packed,length)
    else
      block.call(packed)
    end
    
    0 # return 0 to indicate success
  end
end

#inspect ⇒ String

Inspects the packer.

Returns:

  • (String) —

    The inspected packer.



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# File 'lib/ffi/msgpack/packer.rb', line 161

def inspect
  addr = ('0x%x' % self.pointer.address)

  if @buffer
    "#<#{self.class}:#{addr}: #{@buffer.inspect}>"
  else
    "#<#{self.class}:#{addr}>"
  end
end

#pack(msg) ⇒ Integer

Packs a Msg Object.

Parameters:

  • msg (MsgObject) —

    The Msg Object to pack.

Returns:

  • (Integer) —

    Returns 0 on a successful write, and -1 if an error occurred.



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# File 'lib/ffi/msgpack/packer.rb', line 124

def pack(msg)
  MsgPack.msgpack_pack_object(self,msg)
end

#to_s ⇒ String?

The contents of the buffer.

Returns:

  • (String, nil) —

    The contents of the buffer, or nil if only a callback is being used to write the packed data.



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# File 'lib/ffi/msgpack/packer.rb', line 151

def to_s
  @buffer.to_s if @buffer
end