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-rw-r--r--gmp-6.3.0/mpf/urandomb.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/gmp-6.3.0/mpf/urandomb.c b/gmp-6.3.0/mpf/urandomb.c
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+++ b/gmp-6.3.0/mpf/urandomb.c
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+/* mpf_urandomb (rop, state, nbits) -- Generate a uniform pseudorandom
+ real number between 0 (inclusive) and 1 (exclusive) of size NBITS,
+ using STATE as the random state previously initialized by a call to
+ gmp_randinit().
+
+Copyright 1999-2002 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 either:
+
+ * 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.
+
+or
+
+ * the GNU General Public License as published by the Free Software
+ Foundation; either version 2 of the License, or (at your option) any
+ later version.
+
+or both in parallel, as here.
+
+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 General Public License
+for more details.
+
+You should have received copies of the GNU General Public License and the
+GNU Lesser General Public License along with the GNU MP Library. If not,
+see https://www.gnu.org/licenses/. */
+
+#include "gmp-impl.h"
+
+void
+mpf_urandomb (mpf_ptr rop, gmp_randstate_ptr rstate, mp_bitcnt_t nbits)
+{
+ mp_ptr rp;
+ mp_size_t nlimbs;
+ mp_exp_t exp;
+ mp_size_t prec;
+
+ rp = PTR (rop);
+ nlimbs = BITS_TO_LIMBS (nbits);
+ prec = PREC (rop);
+
+ if (nlimbs > prec + 1 || nlimbs == 0)
+ {
+ nlimbs = prec + 1;
+ nbits = nlimbs * GMP_NUMB_BITS;
+ }
+
+ _gmp_rand (rp, rstate, nbits);
+
+ /* If nbits isn't a multiple of GMP_NUMB_BITS, shift up. */
+ if (nbits % GMP_NUMB_BITS != 0)
+ mpn_lshift (rp, rp, nlimbs, GMP_NUMB_BITS - nbits % GMP_NUMB_BITS);
+
+ exp = 0;
+ while (nlimbs != 0 && rp[nlimbs - 1] == 0)
+ {
+ nlimbs--;
+ exp--;
+ }
+ EXP (rop) = exp;
+ SIZ (rop) = nlimbs;
+}