/* ucl_util.c -- utilities for the UCL library
 
 
 
   This file is part of the UCL data compression library.
 
 
 
   Copyright (C) 1996-2004 Markus Franz Xaver Johannes Oberhumer
 
   All Rights Reserved.
 
 
 
   The UCL 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 UCL 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 UCL 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
 
   <markus@oberhumer.com>
 
   http://www.oberhumer.com/opensource/ucl/
 
 */
 
 
 
 
 
#include "ucl_conf.h"
 
 
 
 
 
/***********************************************************************
 
//
 
************************************************************************/
 
 
 
UCL_PUBLIC(ucl_bool)
 
ucl_assert(int expr)
 
{
 
    return (expr) ? 1 : 0;
 
}
 
 
 
 
 
/***********************************************************************
 
//
 
************************************************************************/
 
 
 
/* If you use the UCL library in a product, you *must* keep this
 
 * copyright string in the executable of your product.
 
.*/
 
 
 
static const char __ucl_copyright[] =
 
    "\r\n\n"
 
    "UCL data compression library.\n"
 
    "$Copyright: UCL (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Markus Franz Xaver Johannes Oberhumer\n"
 
    "<markus@oberhumer.com>\n"
 
    "http://www.oberhumer.com $\n\n"
 
    "$Id: UCL version: v" UCL_VERSION_STRING ", " UCL_VERSION_DATE " $\n"
 
    "$Built: " __DATE__ " " __TIME__ " $\n"
 
    "$Info: " ACC_INFO_OS
 
#if defined(ACC_INFO_OS_POSIX)
 
    "/" ACC_INFO_OS_POSIX
 
#endif
 
    " " ACC_INFO_ARCH
 
#if defined(ACC_INFO_ENDIAN)
 
    "/" ACC_INFO_ENDIAN
 
#endif
 
    " " ACC_INFO_MM
 
    " " ACC_INFO_CC
 
#if defined(ACC_INFO_CCVER)
 
    " " ACC_INFO_CCVER
 
#endif
 
    " $\n";
 
 
 
UCL_PUBLIC(const ucl_bytep)
 
ucl_copyright(void)
 
{
 
#if (ACC_OS_DOS16 && ACC_CC_TURBOC)
 
    return (ucl_voidp) __ucl_copyright;
 
#else
 
    return (const ucl_bytep) __ucl_copyright;
 
#endif
 
}
 
 
 
UCL_PUBLIC(ucl_uint32)
 
ucl_version(void)
 
{
 
    return UCL_VERSION;
 
}
 
 
 
UCL_PUBLIC(const char *)
 
ucl_version_string(void)
 
{
 
    return UCL_VERSION_STRING;
 
}
 
 
 
UCL_PUBLIC(const char *)
 
ucl_version_date(void)
 
{
 
    return UCL_VERSION_DATE;
 
}
 
 
 
UCL_PUBLIC(const ucl_charp)
 
_ucl_version_string(void)
 
{
 
    return UCL_VERSION_STRING;
 
}
 
 
 
UCL_PUBLIC(const ucl_charp)
 
_ucl_version_date(void)
 
{
 
    return UCL_VERSION_DATE;
 
}
 
 
 
 
 
/***********************************************************************
 
// adler32 checksum
 
// adapted from free code by Mark Adler <madler@alumni.caltech.edu>
 
// see http://www.cdrom.com/pub/infozip/zlib/
 
************************************************************************/
 
 
 
#define UCL_BASE 65521u /* largest prime smaller than 65536 */
 
#define UCL_NMAX 5552
 
/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
 
 
 
#define UCL_DO1(buf,i)  {s1 += buf[i]; s2 += s1;}
 
#define UCL_DO2(buf,i)  UCL_DO1(buf,i); UCL_DO1(buf,i+1);
 
#define UCL_DO4(buf,i)  UCL_DO2(buf,i); UCL_DO2(buf,i+2);
 
#define UCL_DO8(buf,i)  UCL_DO4(buf,i); UCL_DO4(buf,i+4);
 
#define UCL_DO16(buf,i) UCL_DO8(buf,i); UCL_DO8(buf,i+8);
 
 
 
UCL_PUBLIC(ucl_uint32)
 
ucl_adler32(ucl_uint32 adler, const ucl_bytep buf, ucl_uint len)
 
{
 
    ucl_uint32 s1 = adler & 0xffff;
 
    ucl_uint32 s2 = (adler >> 16) & 0xffff;
 
    int k;
 
 
 
    if (buf == NULL)
 
        return 1;
 
 
 
    while (len > 0)
 
    {
 
        k = len < UCL_NMAX ? (int) len : UCL_NMAX;
 
        len -= k;
 
        if (k >= 16) do
 
        {
 
            UCL_DO16(buf,0);
 
            buf += 16;
 
            k -= 16;
 
        } while (k >= 16);
 
        if (k != 0) do
 
        {
 
            s1 += *buf++;
 
            s2 += s1;
 
        } while (--k > 0);
 
        s1 %= UCL_BASE;
 
        s2 %= UCL_BASE;
 
    }
 
    return (s2 << 16) | s1;
 
}
 
 
 
 
 
/*
 
vi:ts=4:et
 
*/