Class: Zlib::ZStream

Inherits:
Object
  • Object
show all
Defined in:
lib/pr/zlib.rb,
lib/pr/zlib.rb

Direct Known Subclasses

Deflate, Inflate

Constant Summary collapse

@@final = 
proc do |z|
  proc do
    if z && z.ZSTREAM_IS_READY()
      err = send(z.func.end, z.stream)
      if (err == Z_STREAM_ERROR)
        warn("the stream state was inconsistent.")
      end
      if (err == Z_DATA_ERROR)
        warn("the stream was freed prematurely.")
      end
    end
  end
end

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ ZStream

Returns a new instance of ZStream.



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# File 'lib/pr/zlib.rb', line 497

def initialize
  @z = nil
  ObjectSpace.define_finalizer self, @@final.call(@z)
end

Instance Attribute Details

#buf ⇒ Object

Returns the value of attribute buf.



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# File 'lib/pr/zlib.rb', line 87

def buf
  @buf
end

#flags ⇒ Object

Returns the value of attribute flags.



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# File 'lib/pr/zlib.rb', line 87

def flags
  @flags
end

#func ⇒ Object

Returns the value of attribute func.



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# File 'lib/pr/zlib.rb', line 87

def func
  @func
end

#input ⇒ Object

Returns the value of attribute input.



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# File 'lib/pr/zlib.rb', line 87

def input
  @input
end

#stream ⇒ Object

Returns the value of attribute stream.



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# File 'lib/pr/zlib.rb', line 87

def stream
  @stream
end

#z ⇒ Object (readonly)

Returns the value of attribute z.



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# File 'lib/pr/zlib.rb', line 401

def z
  @z
end

Instance Method Details

#adler ⇒ Object 



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# File 'lib/pr/zlib.rb', line 439

def adler
  @z.stream.adler
end

#avail_in ⇒ Object 



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# File 'lib/pr/zlib.rb', line 421

def avail_in
  @z.input.nil? ? 0 : @z.input.length
end

#avail_out ⇒ Object 



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# File 'lib/pr/zlib.rb', line 403

def avail_out()
  @z.stream.avail_out
end

#avail_out=(size) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 407

def avail_out=(size)
  if @z.buf.nil?
    @z.buf = Bytef.new(0.chr * size)
    @z.stream.next_out = Bytef.new(@z.buf)
    @z.stream.avail_out = size
  elsif @z.stream.avail_out != size
    if @z.buf.offset + size > @z.buf.length
      @z.buf.buffer << 0.chr * (@z.buf.offset + size - @z.buf.length)
    end
    @z.stream.next_out = Bytef.new(@z.buf,@z.buf.offset)
    @z.stream.avail_out = size
  end
end

#close ⇒ Object Also known as: end 



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# File 'lib/pr/zlib.rb', line 453

def close()
  if (!@z.ZSTREAM_IS_READY())
     warn("attempt to close uninitialized zstream ignored.")
     return nil
  end
  if (@z.flags & ZSTREAM_FLAG_IN_STREAM).nonzero?
     warn("attempt to close unfinished zstream reset forced.")
     @z.input = nil
  end

  @z.input = nil
  err = send(@z.func.end,@z.stream)
  if (err != Z_OK)
     raise_zlib_error(err, @z.stream.msg)
  end
  @z.flags = 0
end

#closed? ⇒ Boolean Also known as: ended?

Returns:

  • (Boolean) 


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# File 'lib/pr/zlib.rb', line 448

def closed?
  @z.ZSTREAM_IS_READY()
end

#data_type ⇒ Object 



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# File 'lib/pr/zlib.rb', line 435

def data_type
  @z.stream.data_type
end

#finish ⇒ Object 



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# File 'lib/pr/zlib.rb', line 484

def finish()
  @z.zstream_run("", 0, Z_FINISH)
  @z.zstream_detach_buffer()
end

#finished? ⇒ Boolean Also known as: stream_end?

Returns:

  • (Boolean) 


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# File 'lib/pr/zlib.rb', line 443

def finished?
  @z.ZSTREAM_IS_FINISHED()
end

#flush_next_in ⇒ Object 



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# File 'lib/pr/zlib.rb', line 489

def flush_next_in
  @z.zstream_detach_input
end

#flush_next_out ⇒ Object 



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# File 'lib/pr/zlib.rb', line 493

def flush_next_out
  @z.zstream_detach_buffer
end

#raise_zlib_error(err, msg) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 89

def raise_zlib_error(err, msg)
  msg = zError(err) if msg.nil? || msg==''

  case err
    when Z_STREAM_END
      raise StreamEnd, msg
    when Z_NEED_DICT
      raise NeedDict, msg
    when Z_STREAM_ERROR
      raise StreamError, msg
    when Z_DATA_ERROR
      raise DataError, msg
    when Z_BUF_ERROR
      raise BufError, msg
    when Z_VERSION_ERROR
      raise VersionError, msg
    when Z_MEM_ERROR
      raise MemError, msg
    when Z_ERRNO
      raise SystemCallError, msg
    else
      raise Error, "unknown zlib error #errend: #msgend"
  end
end

#reset ⇒ Object 



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# File 'lib/pr/zlib.rb', line 472

def reset()
  err = send(@z.func.reset,@z.stream)
  if err != Z_OK
    raise_zlib_error(err, @z.stream.msg)
  end
  @z.flags = ZSTREAM_FLAG_READY
  @z.buf = nil
  @z.stream.next_out = 0
  @z.stream.avail_out = 0
  @z.input = nil
end

#total_in ⇒ Object

Raises:



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# File 'lib/pr/zlib.rb', line 425

def total_in
  raise GzipFile::Error,"closed gzip stream" unless @gz.z.ZSTREAM_IS_READY()
  @z.stream.total_in
end

#total_out ⇒ Object

Raises:



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# File 'lib/pr/zlib.rb', line 430

def total_out
  raise GzipFile::Error,"closed gzip stream" unless @gz.z.ZSTREAM_IS_READY()
  @z.stream.total_out
end

#zstream_append_buffer(src, len) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 138

def zstream_append_buffer(src, len)
  if @buf.nil?
    @buf = Bytef.new(src[0,len],len)
    @stream.next_out = Bytef.new(@buf)
    @stream.avail_out = 0
    return
  end
  if (@buf.length < @buf.offset + len)
    @buf.buffer << (0.chr * (@buf.offset + len - @buf.length))
    @stream.avail_out = 0
  else
    if (@stream.avail_out >= len)
       @stream.avail_out -= len
    else
       @stream.avail_out = 0
    end
  end
  @buf.buffer[@buf.offset,len] = src[0,len]
  @buf += len
  @stream.next_out = Bytef.new(@buf, @buf.offset)
end

#zstream_append_input(src, len) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 203

def zstream_append_input(src, len)
  return if (len <= 0)
  src = src.current if src.class != String
  if @input.nil?
    @input = src[0,len]
  else
    @input << src[0,len]
  end
end

#zstream_buffer_ungetc(c) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 191

def zstream_buffer_ungetc(c)
  if (@buf.nil? || (@buf.length - @buf.offset).zero?)
   zstream_expand_buffer()
  end
  @buf.buffer[0,0] = c.chr
  @buf += 1
  if (@stream.avail_out > 0)
   @stream.next_out+=1
   @stream.avail_out-=1
  end
end

#zstream_detach_buffer ⇒ Object 



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# File 'lib/pr/zlib.rb', line 160

def zstream_detach_buffer()
  if @buf.nil?
   dst = ''
  else
   dst = @buf.buffer[0,@buf.offset]
  end

  @buf = Bytef.new(0.chr * ZSTREAM_INITIAL_BUFSIZE)
  @stream.next_out = Bytef.new(@buf)
  @stream.avail_out = ZSTREAM_INITIAL_BUFSIZE
  @buf_filled = 0

  return dst
end

#zstream_detach_input ⇒ Object 



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# File 'lib/pr/zlib.rb', line 232

def zstream_detach_input()
  if @input.nil?
   dst = ''
  else
   dst = @input
  end
  @input = nil
  return dst
end

#zstream_discard_input(len) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 213

def zstream_discard_input(len)
  if (@input.nil? || @input.length <= len)
    @input = nil
  else
    @input[0,len] = ''
  end
end

#zstream_end ⇒ Object 



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# File 'lib/pr/zlib.rb', line 255

def zstream_end()
  if (!ZSTREAM_IS_READY())
    warn("attempt to close uninitialized zstream; ignored.")
    return nil
  end
  if (@flags & ZSTREAM_FLAG_IN_STREAM).nonzero?
    warn("attempt to close unfinished zstream; reset forced.")
    zstream_reset()
  end

  zstream_reset_input()
  err = send(@func.end,@stream)
  if (err != Z_OK)
    raise_zlib_error(err, @stream.msg)
  end
  @flags = 0
  return nil
end

#zstream_expand_buffer ⇒ Object 



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# File 'lib/pr/zlib.rb', line 114

def zstream_expand_buffer()
  if @buf.nil?
    @buf = Bytef.new(0.chr * ZSTREAM_INITIAL_BUFSIZE)
    @stream.next_out = Bytef.new(@buf)
    @stream.avail_out = ZSTREAM_INITIAL_BUFSIZE
    return
  end

  if (@buf.length - @buf.offset >= ZSTREAM_AVAIL_OUT_STEP_MAX)
    @stream.avail_out = ZSTREAM_AVAIL_OUT_STEP_MAX
  else
    inc = @buf.offset / 2
    if (inc < ZSTREAM_AVAIL_OUT_STEP_MIN)
        inc = ZSTREAM_AVAIL_OUT_STEP_MIN
    end
    if @buf.length < @buf.offset + inc
      @buf.buffer << 0.chr * (@buf.offset + inc - @buf.length)
    end
    @stream.avail_out = (inc < ZSTREAM_AVAIL_OUT_STEP_MAX) ?
        inc : ZSTREAM_AVAIL_OUT_STEP_MAX
  end
  @stream.next_out = Bytef.new(@buf,@buf.offset)
end

#zstream_init(func) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 307

def zstream_init(func)
  @flags = 0
  @buf = nil
  @input = nil
  @stream = Z_stream.new
  @stream.msg = ''
  @stream.next_in = nil
  @stream.avail_in = 0
  @stream.next_out = nil
  @stream.avail_out = 0
  @func = func
end

#ZSTREAM_IS_CLOSING ⇒ Object 



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# File 'lib/pr/zlib.rb', line 380

def ZSTREAM_IS_CLOSING()
  !(@flags & ZSTREAM_FLAG_CLOSING).zero?
end

#ZSTREAM_IS_FINISHED ⇒ Object 



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# File 'lib/pr/zlib.rb', line 376

def ZSTREAM_IS_FINISHED()
  !(@flags & ZSTREAM_FLAG_FINISHED).zero?
end

#ZSTREAM_IS_READY ⇒ Object 



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# File 'lib/pr/zlib.rb', line 372

def ZSTREAM_IS_READY()
  !(@flags & ZSTREAM_FLAG_READY).zero?
end

#zstream_passthrough_input ⇒ Object 



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# File 'lib/pr/zlib.rb', line 225

def zstream_passthrough_input()
  if @input
   zstream_append_buffer(@input,@input.length)
   @input = nil
  end
end

#ZSTREAM_READY ⇒ Object 



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# File 'lib/pr/zlib.rb', line 368

def ZSTREAM_READY()
  (@flags |= ZSTREAM_FLAG_READY)
end

#zstream_reset ⇒ Object 



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# File 'lib/pr/zlib.rb', line 242

def zstream_reset()
  err = send(@func.reset,@stream)
  if (err != Z_OK)
    raise_zlib_error(err, @stream.msg)
  end
  @flags = ZSTREAM_FLAG_READY
  @buf = nil
  @buf_filled = 0
  @stream.next_out = 0
  @stream.avail_out = 0
  zstream_reset_input()
end

#zstream_reset_input ⇒ Object 



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# File 'lib/pr/zlib.rb', line 221

def zstream_reset_input()
  @input = nil
end

#zstream_run(src, len, flush) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 320

def zstream_run(src, len, flush)
  if(@input.nil? && len==0)
    @stream.next_in = ''
    @stream.avail_in = 0
  else
    zstream_append_input(src,len)
    @stream.next_in = Bytef.new(@input)
    @stream.avail_in = @input.length
    guard = @input
  end
  if(@stream.avail_out.zero?)
    zstream_expand_buffer()
  end

  loop do
    n = @stream.avail_out
    err = send(@func.run,@stream,flush)
    @buf += n - @stream.avail_out
    if(err == Z_STREAM_END)
      @flags &= ~ZSTREAM_FLAG_IN_STREAM
      @flags |= ZSTREAM_FLAG_FINISHED
      break
    end
    if (err != Z_OK)
      if (flush != Z_FINISH && err == Z_BUF_ERROR && @stream.avail_out > 0)
        @flags |= ZSTREAM_FLAG_IN_STREAM
        break
      end
      @input = nil
      if (@stream.avail_in > 0)
        zstream_append_input(@stream.next_in, @stream.avail_in)
      end
      raise_zlib_error(err, @stream.msg)
    end
    if (@stream.avail_out > 0)
      @flags |= ZSTREAM_FLAG_IN_STREAM
      break
    end
    zstream_expand_buffer()
  end

  @input = nil
  if (@stream.avail_in > 0)
    zstream_append_input(@stream.next_in, @stream.avail_in)
    guard = nil
  end
end

#zstream_shift_buffer(len) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 175

def zstream_shift_buffer(len)
  if (@buf.offset <= len)
    return zstream_detach_buffer()
  end

  dst = @buf.buffer[0, len]
  @buf -= len
  @buf.buffer[0,@buf.offset] = @buf.buffer[len,@buf.offset]
  @stream.next_out = Bytef.new(@buf,@buf.offset)
  @stream.avail_out = @buf.length - @buf.offset
  if (@stream.avail_out > ZSTREAM_AVAIL_OUT_STEP_MAX)
   @stream.avail_out = ZSTREAM_AVAIL_OUT_STEP_MAX
  end
  return dst
end

#zstream_sync(src, len) ⇒ Object 



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# File 'lib/pr/zlib.rb', line 274

def zstream_sync(src, len)
  if @input
   @stream.next_in = Bytef.new(@input)
   @stream.avail_in = @input.length
   err = inflateSync(@stream)
   if (err == Z_OK)
       zstream_discard_input(@input.length - @stream.avail_in)
       zstream_append_input(src, len)
       return true
   end
   zstream_reset_input()
   if (err != Z_DATA_ERROR)
       rest = @stream.next_in.buffer[0,@stream.avail_in]
       raise_zlib_error(err, @stream.msg)
   end
  end

  return false if (len <= 0)

  @stream.next_in = src
  @stream.avail_in = len
  err = inflateSync(@stream)
  if (err == Z_OK)
   zstream_append_input(@stream.next_in, @stream.avail_in)
   return true
  end
  if (err != Z_DATA_ERROR)
   rest = @stream.next_in.buffer[0,@stream.avail_in]
   raise_zlib_error(err, @stream.msg)
  end
  return false
end