source: bootcd/isolinux/syslinux-6.03/com32/lib/memswap.c

/*
 * memswap()
 *
 * Swaps the contents of two nonoverlapping memory areas.
 * This really could be done faster...
 */

#include <string.h>

void memswap(void *m1, void *m2, size_t n)
{
    char *p = m1;
    char *q = m2;
    char tmp;

    while (n--) {
        tmp = *p;
        *p = *q;
        *q = tmp;

        p++;
        q++;
    }
}