lzo1_d.ch

lzo-1.08-src.zip 高效的压缩解压代码

/* lzo1_d.ch -- common decompression stuff

   This file is part of the LZO real-time data compression library.

   Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer
   All Rights Reserved.

   The LZO library is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of
   the License, or (at your option) any later version.

   The LZO library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with the LZO library; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

   Markus F.X.J. Oberhumer
   <[e-mail]>
 */



#if defined(LZO_TEST_DECOMPRESS_OVERRUN)
#  if !defined(LZO_TEST_DECOMPRESS_OVERRUN_INPUT)
#    define LZO_TEST_DECOMPRESS_OVERRUN_INPUT		2
#  endif
#  if !defined(LZO_TEST_DECOMPRESS_OVERRUN_OUTPUT)
#    define LZO_TEST_DECOMPRESS_OVERRUN_OUTPUT		2
#  endif
#  if !defined(LZO_TEST_DECOMPRESS_OVERRUN_LOOKBEHIND)
#    define LZO_TEST_DECOMPRESS_OVERRUN_LOOKBEHIND
#  endif
#endif


/***********************************************************************
// Overrun detection is internally handled by these macros:
//
//   TEST_IP    test input overrun at loop begin
//   NEED_IP    test input overrun at every input byte
//
//   TEST_OP    test output overrun at loop begin
//   NEED_OP    test output overrun at every output byte
//
//   TEST_LOOKBEHIND    test match postion
//
// The fastest decompressor results when testing for no overruns
// and using LZO_EOF_CODE.
************************************************************************/

#undef TEST_IP
#undef TEST_OP
#undef TEST_LOOKBEHIND
#undef NEED_IP
#undef NEED_OP
#undef HAVE_TEST_IP
#undef HAVE_TEST_OP
#undef HAVE_NEED_IP
#undef HAVE_NEED_OP
#undef HAVE_ANY_IP
#undef HAVE_ANY_OP


#if defined(LZO_TEST_DECOMPRESS_OVERRUN_INPUT)
#  if (LZO_TEST_DECOMPRESS_OVERRUN_INPUT >= 1)
#    define TEST_IP				(ip < ip_end)
#  endif
#  if (LZO_TEST_DECOMPRESS_OVERRUN_INPUT >= 2)
#    define NEED_IP(x) \
			if ((lzo_uint)(ip_end - ip) < (lzo_uint)(x))  goto input_overrun
#  endif
#endif

#if defined(LZO_TEST_DECOMPRESS_OVERRUN_OUTPUT)
#  if (LZO_TEST_DECOMPRESS_OVERRUN_OUTPUT >= 1)
#    define TEST_OP				(op <= op_end)
#  endif
#  if (LZO_TEST_DECOMPRESS_OVERRUN_OUTPUT >= 2)
#    undef TEST_OP				/* don't need both of the tests here */
#    define NEED_OP(x) \
			if ((lzo_uint)(op_end - op) < (lzo_uint)(x))  goto output_overrun
#  endif
#endif

#if defined(LZO_TEST_DECOMPRESS_OVERRUN_LOOKBEHIND)
#  define TEST_LOOKBEHIND(m_pos,out)	if (m_pos < out) goto lookbehind_overrun
#else
#  define TEST_LOOKBEHIND(m_pos,op)		((void) 0)
#endif


#if !defined(LZO_EOF_CODE) && !defined(TEST_IP)
   /* if we have no EOF code, we have to test for the end of the input */
#  define TEST_IP				(ip < ip_end)
#endif


#if defined(TEST_IP)
#  define HAVE_TEST_IP
#else
#  define TEST_IP				1
#endif
#if defined(TEST_OP)
#  define HAVE_TEST_OP
#else
#  define TEST_OP				1
#endif

#if defined(NEED_IP)
#  define HAVE_NEED_IP
#else
#  define NEED_IP(x)			((void) 0)
#endif
#if defined(NEED_OP)
#  define HAVE_NEED_OP
#else
#  define NEED_OP(x)			((void) 0)
#endif


#if defined(HAVE_TEST_IP) || defined(HAVE_NEED_IP)
#  define HAVE_ANY_IP
#endif
#if defined(HAVE_TEST_OP) || defined(HAVE_NEED_OP)
#  define HAVE_ANY_OP
#endif



/*
vi:ts=4:et
*/