/* bignum_copy.c - copy a bignum
Copyright (C) 1987 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS 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 1, or (at your option)
GAS 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 GAS; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#define bzero(s,n) memset(s,0,n)
#define bcopy(from,to,n) memcpy(to,from,n)
* Copy a bignum from in to out.
* If the output is shorter than the input, copy lower-order littlenums.
* Return 0 or the number of significant littlenums dropped.
* Assumes littlenum arrays are densely packed: no unused chars between
* the littlenums. Uses bcopy() to move littlenums, and wants to
* know length (in chars) of the input bignum.
bignum_copy (in
, in_length
, out
, out_length
)
register LITTLENUM_TYPE
* in
;
register int in_length
; /* in sizeof(littlenum)s */
register LITTLENUM_TYPE
* out
;
register int out_length
; /* in sizeof(littlenum)s */
register int significant_littlenums_dropped
;
if (out_length
< in_length
)
register LITTLENUM_TYPE
* p
; /* -> most significant (non-zero) input littlenum. */
bcopy ((char *)in
, (char *)out
, out_length
<< LITTLENUM_SHIFT
);
for (p
= in
+ in_length
- 1; p
>= in
; -- p
)
significant_littlenums_dropped
= p
- in
- in_length
+ 1;
if (significant_littlenums_dropped
< 0)
significant_littlenums_dropped
= 0;
bcopy ((char *)in
, (char *)out
, in_length
<< LITTLENUM_SHIFT
);
if (out_length
> in_length
)
bzero ((char *)(out
+ out_length
), (out_length
- in_length
) << LITTLENUM_SHIFT
);
significant_littlenums_dropped
= 0;
return (significant_littlenums_dropped
);