| /* gmp_urandomb_ui -- random bits returned in a ulong. |
| |
| Copyright 2003, 2004 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 "gmp.h" |
| #include "gmp-impl.h" |
| |
| |
| /* Currently bits>=BITS_PER_ULONG is quietly truncated to BITS_PER_ULONG, |
| maybe this should raise an exception or something. */ |
| |
| unsigned long |
| gmp_urandomb_ui (gmp_randstate_ptr rstate, unsigned long bits) |
| { |
| mp_limb_t a[LIMBS_PER_ULONG]; |
| |
| /* start with zeros, since if bits==0 then _gmp_rand will store nothing at |
| all, or if bits <= GMP_NUMB_BITS then it will store only a[0] */ |
| a[0] = 0; |
| #if LIMBS_PER_ULONG > 1 |
| a[1] = 0; |
| #endif |
| |
| _gmp_rand (a, rstate, MIN (bits, BITS_PER_ULONG)); |
| |
| #if LIMBS_PER_ULONG == 1 |
| return a[0]; |
| #else |
| return a[0] | (a[1] << GMP_NUMB_BITS); |
| #endif |
| } |