test/read_joiner.rb

   1 class ReadJoiner
   2   include IO::Readable
   3   extend  IO::Openable
   4
   5   def initialize(*streams)
   6     @streams = streams
   7     rewind
   8   end
   9
  10   def sysread(length)
  11     buffer = ""
  12     return buffer if length == 0
  13     while buffer.length < length && @streams[@index]
  14       begin
  15         buffer << @streams[@index].sysread(length-buffer.length)
  16       rescue EOFError
  17         @index += 1
  18       end
  19     end
  20     return buffer if buffer.length == length || buffer.length > 0
  21     raise EOFError, "end of file reached", caller
  22   end
  23
  24   def close_read
  25     @streams.each {|s| s.close}
  26     @index = @streams.size - 1 if @index >= @streams.size
  27     nil
  28   end
  29
  30   def closed_read?
  31     @streams.all? {|s|s.closed?}
  32   end
  33
  34   def rewind
  35     @streams.each {|s| s.rewind}
  36     self.lineno = @index = 0
  37   end
  38
  39 end
  40