vasilito
ff4ff35918
Red Bear OS is a full fork. All sources must be available from git clone with zero network access. Removed gitignore rules that excluded fetched source trees under recipes/*/source/, local/recipes/kde/*/source/, local/recipes/qt/*/source/, and vendor source trees. Build artifacts (target/, build/, source.tar, *.o, *.so) remain excluded. 127291 files added — kernel, relibc, base, bootloader, pkgar, all KDE/Qt frameworks, mesa, wayland, DRM drivers, and every other recipe source.
99 lines
2.6 KiB
C
99 lines
2.6 KiB
C
/* mpz_urandomm (rop, state, n) -- Generate a uniform pseudorandom
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integer in the range 0 to N-1, using STATE as the random state
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previously initialized by a call to gmp_randinit().
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Copyright 2000, 2002, 2012, 2015 Free Software Foundation, Inc.
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This file is part of the GNU MP Library.
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The GNU MP Library is free software; you can redistribute it and/or modify
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it under the terms of either:
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* the GNU Lesser General Public License as published by the Free
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Software Foundation; either version 3 of the License, or (at your
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option) any later version.
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or
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* the GNU General Public License as published by the Free Software
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Foundation; either version 2 of the License, or (at your option) any
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later version.
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or both in parallel, as here.
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The GNU MP Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received copies of the GNU General Public License and the
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GNU Lesser General Public License along with the GNU MP Library. If not,
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see https://www.gnu.org/licenses/. */
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#include "gmp-impl.h"
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#include "longlong.h" /* for count_leading_zeros */
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#define MAX_URANDOMM_ITER 80
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void
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mpz_urandomm (mpz_ptr rop, gmp_randstate_ptr rstate, mpz_srcptr n)
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{
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mp_ptr rp, np;
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mp_size_t nbits, size;
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mp_limb_t nh;
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int count;
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int pow2;
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int cmp;
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TMP_DECL;
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size = ABSIZ (n);
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if (UNLIKELY (size == 0))
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DIVIDE_BY_ZERO;
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np = PTR (n);
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nh = np[size - 1];
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/* Detect whether n is a power of 2. */
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pow2 = POW2_P (nh) && (size == 1 || mpn_zero_p (np, size - 1));
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count_leading_zeros (count, nh);
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nbits = size * GMP_NUMB_BITS - (count - GMP_NAIL_BITS) - pow2;
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if (nbits == 0) /* nbits == 0 means that n was == 1. */
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{
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SIZ (rop) = 0;
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return;
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}
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TMP_MARK;
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if (rop == n)
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{
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mp_ptr tp;
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tp = TMP_ALLOC_LIMBS (size);
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MPN_COPY (tp, np, size);
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np = tp;
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}
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/* Here the allocated size can be one too much if n is a power of
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(2^GMP_NUMB_BITS) but it's convenient for using mpn_cmp below. */
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rp = MPZ_NEWALLOC (rop, size);
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/* Clear last limb to prevent the case in which size is one too much. */
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rp[size - 1] = 0;
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count = MAX_URANDOMM_ITER; /* Set iteration count limit. */
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do
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{
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_gmp_rand (rp, rstate, nbits);
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MPN_CMP (cmp, rp, np, size);
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}
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while (cmp >= 0 && --count != 0);
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if (count == 0)
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/* Too many iterations; return result mod n == result - n */
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mpn_sub_n (rp, rp, np, size);
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MPN_NORMALIZE (rp, size);
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SIZ (rop) = size;
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TMP_FREE;
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}
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