old-cross-binutils/gas/bignum-copy.c
Ken Raeburn 4b0dd31c9f Lots of changes from Eric Youngdale, mostly for VAX and VMS support.
Also, fix another goof in read.c, which caused ".data" not to work...
1993-01-07 10:48:49 +00:00

79 lines
2.3 KiB
C

/* bignum_copy.c - copy a bignum
Copyright (C) 1987, 1990, 1991, 1992 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 2, or (at your option)
any later version.
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. */
#include "as.h"
/*
* bignum_copy ()
*
* 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 memcpy() to move littlenums, and wants to
* know length (in chars) of the input bignum.
*/
/* void */
int
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 */
{
int significant_littlenums_dropped;
if (out_length < in_length)
{
LITTLENUM_TYPE *p; /* -> most significant (non-zero) input
littlenum. */
memcpy ((void *) out, (void *) in,
out_length << LITTLENUM_SHIFT);
for (p = in + in_length - 1; p >= in; --p)
{
if (*p)
break;
}
significant_littlenums_dropped = p - in - in_length + 1;
if (significant_littlenums_dropped < 0)
{
significant_littlenums_dropped = 0;
}
}
else
{
memcpy ((char *) out, (char *) in,
in_length << LITTLENUM_SHIFT);
if (out_length > in_length)
{
memset ((char *) (out + in_length),
'\0', (out_length - in_length) << LITTLENUM_SHIFT);
}
significant_littlenums_dropped = 0;
}
return (significant_littlenums_dropped);
} /* bignum_copy() */
/* end of bignum-copy.c */