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Diffstat (limited to 'src/lzo_util.c')
| -rw-r--r-- | src/lzo_util.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/src/lzo_util.c b/src/lzo_util.c new file mode 100644 index 0000000..1e4a9e3 --- /dev/null +++ b/src/lzo_util.c @@ -0,0 +1,167 @@ +/* lzo_util.c -- utilities for the LZO library + + This file is part of the LZO real-time data compression library. + + Copyright (C) 2011 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2010 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2009 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer + Copyright (C) 1996 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., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + + Markus F.X.J. Oberhumer + <markus@oberhumer.com> + http://www.oberhumer.com/opensource/lzo/ + */ + + +#include "lzo_conf.h" + + +/*********************************************************************** +// +************************************************************************/ + +/* If you use the LZO library in a product, I would appreciate that you + * keep this copyright string in the executable of your product. +.*/ + +static const char __lzo_copyright[] = +#if !defined(__LZO_IN_MINLZO) + /* save space as some people want a really small decompressor */ + LZO_VERSION_STRING; +#else + "\r\n\n" + "LZO data compression library.\n" + "$Copyright: LZO Copyright (C) 1996-2011 Markus Franz Xaver Johannes Oberhumer\n" + "<markus@oberhumer.com>\n" + "http://www.oberhumer.com $\n\n" + "$Id: LZO version: v" LZO_VERSION_STRING ", " LZO_VERSION_DATE " $\n" + "$Info: " LZO_INFO_STRING " $\n"; +#endif + + +LZO_PUBLIC(const lzo_bytep) +lzo_copyright(void) +{ +#if (LZO_OS_DOS16 && LZO_CC_TURBOC) + return (lzo_voidp) __lzo_copyright; +#else + return (const lzo_bytep) __lzo_copyright; +#endif +} + +LZO_PUBLIC(unsigned) +lzo_version(void) +{ + return LZO_VERSION; +} + +LZO_PUBLIC(const char *) +lzo_version_string(void) +{ + return LZO_VERSION_STRING; +} + +LZO_PUBLIC(const char *) +lzo_version_date(void) +{ + return LZO_VERSION_DATE; +} + +LZO_PUBLIC(const lzo_charp) +_lzo_version_string(void) +{ + return LZO_VERSION_STRING; +} + +LZO_PUBLIC(const lzo_charp) +_lzo_version_date(void) +{ + return LZO_VERSION_DATE; +} + + +/*********************************************************************** +// adler32 checksum +// adapted from free code by Mark Adler <madler@alumni.caltech.edu> +// see http://www.zlib.org/ +************************************************************************/ + +#define LZO_BASE 65521u /* largest prime smaller than 65536 */ +#define LZO_NMAX 5552 +/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ + +#define LZO_DO1(buf,i) s1 += buf[i]; s2 += s1 +#define LZO_DO2(buf,i) LZO_DO1(buf,i); LZO_DO1(buf,i+1); +#define LZO_DO4(buf,i) LZO_DO2(buf,i); LZO_DO2(buf,i+2); +#define LZO_DO8(buf,i) LZO_DO4(buf,i); LZO_DO4(buf,i+4); +#define LZO_DO16(buf,i) LZO_DO8(buf,i); LZO_DO8(buf,i+8); + +LZO_PUBLIC(lzo_uint32) +lzo_adler32(lzo_uint32 adler, const lzo_bytep buf, lzo_uint len) +{ + lzo_uint32 s1 = adler & 0xffff; + lzo_uint32 s2 = (adler >> 16) & 0xffff; + unsigned k; + + if (buf == NULL) + return 1; + + while (len > 0) + { + k = len < LZO_NMAX ? (unsigned) len : LZO_NMAX; + len -= k; + if (k >= 16) do + { + LZO_DO16(buf,0); + buf += 16; + k -= 16; + } while (k >= 16); + if (k != 0) do + { + s1 += *buf++; + s2 += s1; + } while (--k > 0); + s1 %= LZO_BASE; + s2 %= LZO_BASE; + } + return (s2 << 16) | s1; +} + +#undef LZO_DO1 +#undef LZO_DO2 +#undef LZO_DO4 +#undef LZO_DO8 +#undef LZO_DO16 + + +/* +vi:ts=4:et +*/ |