rt-thread/components/external/lzo

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 miniLZO -- mini subset of the LZO real-time data compression library

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 Author  : Markus Franz Xaver Johannes Oberhumer

           <markus@oberhumer.com>

           http://www.oberhumer.com/opensource/lzo/

 Version : 2.06

 Date    : 12 Aug 2011



 I've created miniLZO for projects where it is inconvenient to

 include (or require) the full LZO source code just because you

 want to add a little bit of data compression to your application.



 miniLZO implements the LZO1X-1 compressor and both the standard and

 safe LZO1X decompressor. Apart from fast compression it also useful

 for situations where you want to use pre-compressed data files (which

 must have been compressed with LZO1X-999).



 miniLZO consists of one C source file and three header files:

    minilzo.c

    minilzo.h, lzoconf.h, lzodefs.h



 To use miniLZO just copy these files into your source directory, add

 minilzo.c to your Makefile and #include minilzo.h from your program.

 Note: you also must distribute this file ('README.LZO') with your project.



 minilzo.o compiles to about 6 KiB (using gcc or Visual C on an i386), and

 the sources are about 30 KiB when packed with zip - so there's no more

 excuse that your application doesn't support data compression :-)



 For more information, documentation, example programs and other support

 files (like Makefiles and build scripts) please download the full LZO

 package from

    http://www.oberhumer.com/opensource/lzo/



 Have fun,

  Markus





 P.S. minilzo.c is generated automatically from the LZO sources and

      therefore functionality is completely identical





 Appendix A: building miniLZO

 ----------------------------

 miniLZO is written such a way that it should compile and run

 out-of-the-box on most machines.



 If you are running on a very unusual architecture and lzo_init() fails then

 you should first recompile with '-DLZO_DEBUG' to see what causes the failure.

 The most probable case is something like 'sizeof(void *) != sizeof(size_t)'.

 After identifying the problem you can compile by adding some defines

 like '-DSIZEOF_VOID_P=8' to your Makefile.



 The best solution is (of course) using Autoconf - if your project uses

 Autoconf anyway just add '-DMINILZO_HAVE_CONFIG_H' to your compiler

 flags when compiling minilzo.c. See the LZO distribution for an example

 how to set up configure.ac.





 Appendix B: list of public functions available in miniLZO

 ---------------------------------------------------------

 Library initialization

    lzo_init()



 Compression

    lzo1x_1_compress()



 Decompression

    lzo1x_decompress()

    lzo1x_decompress_safe()



 Checksum functions

    lzo_adler32()



 Version functions

    lzo_version()

    lzo_version_string()

    lzo_version_date()



 Portable (but slow) string functions

    lzo_memcmp()

    lzo_memcpy()

    lzo_memmove()

    lzo_memset()





 Appendix C: suggested macros for 'configure.ac' when using Autoconf

 -------------------------------------------------------------------

 Checks for typedefs and structures

    AC_CHECK_TYPE(ptrdiff_t,long)

    AC_TYPE_SIZE_T

    AC_CHECK_SIZEOF(short)

    AC_CHECK_SIZEOF(int)

    AC_CHECK_SIZEOF(long)

    AC_CHECK_SIZEOF(long long)

    AC_CHECK_SIZEOF(__int64)

    AC_CHECK_SIZEOF(void *)

    AC_CHECK_SIZEOF(size_t)

    AC_CHECK_SIZEOF(ptrdiff_t)



 Checks for compiler characteristics

    AC_C_CONST



 Checks for library functions

    AC_CHECK_FUNCS(memcmp memcpy memmove memset)





 Appendix D: Copyright

 ---------------------

 LZO and miniLZO are Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001,

 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011

 Markus Franz Xaver Oberhumer <markus@oberhumer.com>.



 LZO and miniLZO are distributed under the terms of the GNU General

 Public License (GPL).  See the file COPYING.



 Special licenses for commercial and other applications which

 are not willing to accept the GNU General Public License

 are available by contacting the author.