--- /dev/null
+/* mpz_inp_raw -- read an mpz_t in raw format.
+
+Copyright 2001, 2002, 2005 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 Lesser General Public License as published by
+the Free Software Foundation; either version 3 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 Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
+
+#include <stdio.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+/* NTOH_LIMB_FETCH fetches a limb which is in network byte order (ie. big
+ endian) and produces a normal host byte order result. */
+
+#if HAVE_LIMB_BIG_ENDIAN
+#define NTOH_LIMB_FETCH(limb, src) do { (limb) = *(src); } while (0)
+#endif
+
+#if HAVE_LIMB_LITTLE_ENDIAN
+#define NTOH_LIMB_FETCH(limb, src) BSWAP_LIMB_FETCH (limb, src)
+#endif
+
+#ifndef NTOH_LIMB_FETCH
+#define NTOH_LIMB_FETCH(limb, src) \
+ do { \
+ const unsigned char *__p = (const unsigned char *) (src); \
+ mp_limb_t __limb; \
+ int __i; \
+ __limb = 0; \
+ for (__i = 0; __i < BYTES_PER_MP_LIMB; __i++) \
+ __limb = (__limb << 8) | __p[__i]; \
+ (limb) = __limb; \
+ } while (0)
+#endif
+
+
+/* Enhancement: The byte swap loop ought to be safe to vectorize on Cray
+ etc, but someone who knows what they're doing needs to check it. */
+
+size_t
+mpz_inp_raw (mpz_ptr x, FILE *fp)
+{
+ unsigned char csize_bytes[4];
+ mp_size_t csize, abs_xsize, i;
+ size_t abs_csize;
+ char *cp;
+ mp_ptr xp, sp, ep;
+ mp_limb_t slimb, elimb;
+
+ if (fp == 0)
+ fp = stdin;
+
+ /* 4 bytes for size */
+ if (fread (csize_bytes, sizeof (csize_bytes), 1, fp) != 1)
+ return 0;
+
+ csize =
+ ( (mp_size_t) csize_bytes[0] << 24)
+ + ((mp_size_t) csize_bytes[1] << 16)
+ + ((mp_size_t) csize_bytes[2] << 8)
+ + ((mp_size_t) csize_bytes[3]);
+
+ /* Sign extend if necessary.
+ Could write "csize -= ((csize & 0x80000000L) << 1)", but that tickles a
+ bug in gcc 3.0 for powerpc64 on AIX. */
+ if (sizeof (csize) > 4 && csize & 0x80000000L)
+ csize -= 0x80000000L << 1;
+
+ abs_csize = ABS (csize);
+
+ /* round up to a multiple of limbs */
+ abs_xsize = (abs_csize*8 + GMP_NUMB_BITS-1) / GMP_NUMB_BITS;
+
+ if (abs_xsize != 0)
+ {
+ MPZ_REALLOC (x, abs_xsize);
+ xp = PTR(x);
+
+ /* Get limb boundaries right in the read, for the benefit of the
+ non-nails case. */
+ xp[0] = 0;
+ cp = (char *) (xp + abs_xsize) - abs_csize;
+ if (fread (cp, abs_csize, 1, fp) != 1)
+ return 0;
+
+ if (GMP_NAIL_BITS == 0)
+ {
+ /* Reverse limbs to least significant first, and byte swap. If
+ abs_xsize is odd then on the last iteration elimb and slimb are
+ the same. It doesn't seem extra code to handle that case
+ separately, to save an NTOH. */
+ sp = xp;
+ ep = xp + abs_xsize-1;
+ for (i = 0; i < (abs_xsize+1)/2; i++)
+ {
+ NTOH_LIMB_FETCH (elimb, ep);
+ NTOH_LIMB_FETCH (slimb, sp);
+ *sp++ = elimb;
+ *ep-- = slimb;
+ }
+ }
+ else
+ {
+ /* It ought to be possible to do the transformation in-place, but
+ for now it's easier to use an extra temporary area. */
+ mp_limb_t byte, limb;
+ int bits;
+ mp_size_t tpos;
+ mp_ptr tp;
+ TMP_DECL;
+
+ TMP_MARK;
+ tp = TMP_ALLOC_LIMBS (abs_xsize);
+ limb = 0;
+ bits = 0;
+ tpos = 0;
+ for (i = abs_csize-1; i >= 0; i--)
+ {
+ byte = (unsigned char) cp[i];
+ limb |= (byte << bits);
+ bits += 8;
+ if (bits >= GMP_NUMB_BITS)
+ {
+ ASSERT (tpos < abs_xsize);
+ tp[tpos++] = limb & GMP_NUMB_MASK;
+ bits -= GMP_NUMB_BITS;
+ ASSERT (bits < 8);
+ limb = byte >> (8 - bits);
+ }
+ }
+ if (bits != 0)
+ {
+ ASSERT (tpos < abs_xsize);
+ tp[tpos++] = limb;
+ }
+ ASSERT (tpos == abs_xsize);
+
+ MPN_COPY (xp, tp, abs_xsize);
+ TMP_FREE;
+ }
+
+ /* GMP 1.x mpz_out_raw wrote high zero bytes, strip any high zero
+ limbs resulting from this. Should be a non-zero value here, but
+ for safety don't assume that. */
+ MPN_NORMALIZE (xp, abs_xsize);
+ }
+
+ SIZ(x) = (csize >= 0 ? abs_xsize : -abs_xsize);
+ return abs_csize + 4;
+}
projects / msp430-gcc.git / blobdiff