diff options
| -rw-r--r-- | mpf/urandomb.c | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/mpf/urandomb.c b/mpf/urandomb.c index d4d6817c9..ba736cd4e 100644 --- a/mpf/urandomb.c +++ b/mpf/urandomb.c @@ -1,6 +1,7 @@ -/* mpf_urandomb (rop, state) -- Generate a uniform pseudorandom real - number between 0 (inclusive) and 1 (exclusive), using STATE as the - random state previously initialized by a call to gmp_randinit(). +/* 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 (C) 1999, 2000 Free Software Foundation, Inc. @@ -24,15 +25,14 @@ MA 02111-1307, USA. */ #include "gmp.h" #include "gmp-impl.h" -/* FIXME: Rename file to urandomb.c. */ - void #if __STDC__ -mpf_urandomb (mpf_t rop, gmp_randstate_t rstate) +mpf_urandomb (mpf_t rop, gmp_randstate_t rstate, unsigned long int nbits) #else -mpf_urandomb (rop, rstate) +mpf_urandomb (rop, rstate, nbits) mpf_t rop; gmp_randstate_t rstate; + unsigned long int nbits; #endif { mp_ptr rp; @@ -40,9 +40,17 @@ mpf_urandomb (rop, rstate) mp_exp_t exp; rp = PTR (rop); - nlimbs = PREC (rop); + nlimbs = (nbits + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB; + + _gmp_rand (rp, rstate, nbits); - _gmp_rand (rp, rstate, nlimbs * BITS_PER_MP_LIMB); + /* If nbits isn't a multiple of BITS_PER_MP_LIMB, shift up. */ + if (nlimbs != 0) + { + if (nbits % BITS_PER_MP_LIMB != 0) + mpn_lshift (rp, rp, nlimbs, + BITS_PER_MP_LIMB - nbits % BITS_PER_MP_LIMB); + } exp = 0; while (nlimbs != 0 && rp[nlimbs - 1] == 0) @@ -53,13 +61,4 @@ mpf_urandomb (rop, rstate) EXP (rop) = exp; SIZ (rop) = nlimbs; -#if 0 - /* If nbits isn't a multiple of BITS_PER_MP_LIMB, shift. */ - if (nlimbs != 0) - { - if (nbits % BITS_PER_MP_LIMB != 0) - mpn_lshift (rp, rp, nlimbs, - BITS_PER_MP_LIMB - nbits % BITS_PER_MP_LIMB); - } -#endif } |