memset.c

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/*****************************************************************************************
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 $Id: memset_8c-source.html 88 2016-01-12 00:11:29Z reddawg $

*****************************************************************************************/

#include <string.h>

#define wsize   sizeof(uInt)
#define wmask   (wsize - 1)
#define VAL     c0
#define WIDEVAL c

void *memset(void *dst0, int c0, size_t length) {
  size_t t;
  uInt c;
  uInt8 *dst;

  dst = dst0;

        if (length < 3 * wsize) {
                while (length != 0) {
                        *dst++ = VAL;
                        --length;
                }
                return(dst0);
        }

        if ((c = (uInt8)c0) != 0) {    /* Fill the word. */
                c = (c << 8) | c;       /* u_int is 16 bits. */
                c = (c << 16) | c;      /* u_int is 32 bits. */
        }

        /* Align destination by filling in bytes. */
        if ((t = (long)dst & wmask) != 0) {
                t = wsize - t;
                length -= t;
                do {
                        *dst++ = VAL;
                } while (--t != 0);
        }

        /* Fill words.  Length was >= 2*words so we know t >= 1 here. */
        t = length / wsize;
        do {
                *(u_int *)dst = WIDEVAL;
                dst += wsize;
        } while (--t != 0);

        /* Mop up trailing bytes, if any. */
        t = length & wmask;
        if (t != 0)
                do {
                        *dst++ = VAL;
                } while (--t != 0);
        return(dst0);
  }


/***
 $Log: memset_8c-source.html,v $
 Revision 1.7  2006/12/15 17:47:06  reddawg
 Updates

 Revision 1.1.1.1  2006/06/01 12:46:16  reddawg
 ubix2

 Revision 1.2  2005/10/12 00:13:37  reddawg
 Removed

 Revision 1.1.1.1  2005/09/26 17:24:12  reddawg
 no message

 Revision 1.1  2004/07/28 16:20:10  reddawg
 forgot this file

 END
 ***/

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