freebsd-dev/contrib/libgmp/mpz/inp_raw.c
Mark Murray aa9bc17601 Clean import of libgmp 2.0.2, with only the non-x86 bits removed.
BMakefiles and other bits will follow.

Requested by:	Andrey Chernov
Made world by:	Chuck Robey
1996-10-20 08:49:26 +00:00

102 lines
2.5 KiB
C

/* mpz_inp_raw -- Input a mpz_t in raw, but endianess, and wordsize
independent format (as output by mpz_out_raw).
Copyright (C) 1991, 1993, 1994, 1995 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library 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 Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"
size_t
#if __STDC__
mpz_inp_raw (mpz_ptr x, FILE *stream)
#else
mpz_inp_raw (x, stream)
mpz_ptr x;
FILE *stream;
#endif
{
int i;
mp_size_t s;
mp_size_t xsize;
mp_ptr xp;
unsigned int c;
mp_limb_t x_limb;
mp_size_t in_bytesize;
int neg_flag;
if (stream == 0)
stream = stdin;
/* Read 4-byte size */
in_bytesize = 0;
for (i = 4 - 1; i >= 0; i--)
{
c = fgetc (stream);
in_bytesize = (in_bytesize << BITS_PER_CHAR) | c;
}
/* Size is stored as a 32 bit word; sign extend in_bytesize for non-32 bit
machines. */
if (sizeof (mp_size_t) > 4)
in_bytesize |= (-(in_bytesize < 0)) << 31;
neg_flag = in_bytesize < 0;
in_bytesize = ABS (in_bytesize);
xsize = (in_bytesize + BYTES_PER_MP_LIMB - 1) / BYTES_PER_MP_LIMB;
if (xsize == 0)
{
x->_mp_size = 0;
return 4; /* we've read 4 bytes */
}
if (x->_mp_alloc < xsize)
_mpz_realloc (x, xsize);
xp = x->_mp_d;
x_limb = 0;
for (i = (in_bytesize - 1) % BYTES_PER_MP_LIMB; i >= 0; i--)
{
c = fgetc (stream);
x_limb = (x_limb << BITS_PER_CHAR) | c;
}
xp[xsize - 1] = x_limb;
for (s = xsize - 2; s >= 0; s--)
{
x_limb = 0;
for (i = BYTES_PER_MP_LIMB - 1; i >= 0; i--)
{
c = fgetc (stream);
x_limb = (x_limb << BITS_PER_CHAR) | c;
}
xp[s] = x_limb;
}
if (c == EOF)
return 0; /* error */
MPN_NORMALIZE (xp, xsize);
x->_mp_size = neg_flag ? -xsize : xsize;
return in_bytesize + 4;
}