`class CompositeReadIO`

Concatenate together multiple IO objects into a single, composite IO object for purposes of reading as a single stream.

crio = CompositeReadIO.new(StringIO.new('one'),
                           StringIO.new('two'),
                           StringIO.new('three'))
puts crio.read # => "onetwothree"

Definitions

`def initialize(*ios)`

Create a new composite-read IO from the arguments, all of which should respond to #read in a manner consistent with IO.

Implementation

def initialize(*ios)
  @ios = ios.flatten
  @index = 0
end

`def close`

Close all the underyling IOs.

Implementation

def close
  @ios.each do |io|
    io.close if io.respond_to?(:close)
  end

  @ios = nil
  @index = 0
end

`def read(length = nil, outbuf = nil)`

Read from IOs in order until length bytes have been received.

Implementation

def read(length = nil, outbuf = nil)
  if @ios.nil?
    raise IOError, "CompositeReadIO is closed!"
  end

  got_result = false
  outbuf = outbuf ? outbuf.replace("") : String.new

  while io = current_io
    if result = io.read(length)
      got_result ||= !result.nil?
      result.force_encoding("BINARY") if result.respond_to?(:force_encoding)
      outbuf << result
      length -= result.length if length
      break if length == 0
    end
    advance_io
  end
  (!got_result && length) ? nil : outbuf
end