lib/bcopy.c

   1 /* bcopy.c -- copy memory.
   2    Copy LENGTH bytes from SOURCE to DEST.  Does not null-terminate.
   3    In the public domain.
   4    By David MacKenzie <djm@gnu.ai.mit.edu>.  */
   5
   6 #include <stddef.h>
   7
   8 void
   9 bcopy (void const *source0, void *dest0, size_t length)
  10 {
  11   char const *source = source0;
  12   char *dest = dest0;
  13   if (source < dest)
  14     /* Moving from low mem to hi mem; start at end.  */
  15     for (source += length, dest += length; length; --length)
  16       *--dest = *--source;
  17   else if (source != dest)
  18     /* Moving from hi mem to low mem; start at beginning.  */
  19     for (; length; --length)
  20       *dest++ = *source++;
  21 }