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author | markm <markm@FreeBSD.org> | 1995-11-12 14:40:41 +0000 |
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committer | markm <markm@FreeBSD.org> | 1995-11-12 14:40:41 +0000 |
commit | d938bb78837327b46dc34873a6eb60c002605808 (patch) | |
tree | d720c213b0c2f268c17d14276e809e876bd37dc8 /gnu/lib/libgmp/mpz_sqrtrem.c | |
parent | 7e662b2efdf7b11bed05bdd944746d7b7d0e56af (diff) | |
download | FreeBSD-src-d938bb78837327b46dc34873a6eb60c002605808.zip FreeBSD-src-d938bb78837327b46dc34873a6eb60c002605808.tar.gz |
GNU MP (Multiprecision) library. This is needed by secure RPC (being
done by Bill Paul) and various other BSD programs.
Obtained from:FSF
Diffstat (limited to 'gnu/lib/libgmp/mpz_sqrtrem.c')
-rw-r--r-- | gnu/lib/libgmp/mpz_sqrtrem.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/gnu/lib/libgmp/mpz_sqrtrem.c b/gnu/lib/libgmp/mpz_sqrtrem.c new file mode 100644 index 0000000..c846c95 --- /dev/null +++ b/gnu/lib/libgmp/mpz_sqrtrem.c @@ -0,0 +1,105 @@ +/* mpz_sqrtrem(root,rem,x) -- Set ROOT to floor(sqrt(X)) and REM + to the remainder, i.e. X - ROOT**2. + +Copyright (C) 1991 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 General Public License as published by +the Free Software Foundation; either version 2, 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 General Public License for more details. + +You should have received a copy of the GNU General Public License +along with the GNU MP Library; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "gmp.h" +#include "gmp-impl.h" + +#ifndef BERKELEY_MP +void +#ifdef __STDC__ +mpz_sqrtrem (MP_INT *root, MP_INT *rem, const MP_INT *op) +#else +mpz_sqrtrem (root, rem, op) + MP_INT *root; + MP_INT *rem; + const MP_INT *op; +#endif +#else /* BERKELEY_MP */ +void +#ifdef __STDC__ +msqrt (const MP_INT *op, MP_INT *root, MP_INT *rem) +#else +msqrt (op, root, rem) + const MP_INT *op; + MP_INT *root; + MP_INT *rem; +#endif +#endif /* BERKELEY_MP */ +{ + mp_size op_size, root_size, rem_size; + mp_ptr root_ptr, op_ptr; + mp_ptr free_me = NULL; + mp_size free_me_size; + + op_size = op->size; + if (op_size < 0) + op_size = 1 / (op_size > 0); /* Divide by zero for negative OP. */ + + if (rem->alloc < op_size) + _mpz_realloc (rem, op_size); + + /* The size of the root is accurate after this simple calculation. */ + root_size = (op_size + 1) / 2; + + root_ptr = root->d; + op_ptr = op->d; + + if (root->alloc < root_size) + { + if (root_ptr == op_ptr) + { + free_me = root_ptr; + free_me_size = root->alloc; + } + else + (*_mp_free_func) (root_ptr, root->alloc * BYTES_PER_MP_LIMB); + + root->alloc = root_size; + root_ptr = (mp_ptr) (*_mp_allocate_func) (root_size * BYTES_PER_MP_LIMB); + root->d = root_ptr; + } + else + { + /* Make OP not overlap with ROOT. */ + if (root_ptr == op_ptr) + { + /* ROOT and OP are identical. Allocate temporary space for OP. */ + op_ptr = (mp_ptr) alloca (op_size * BYTES_PER_MP_LIMB); + /* Copy to the temporary space. Hack: Avoid temporary variable + by using ROOT_PTR. */ + MPN_COPY (op_ptr, root_ptr, op_size); + } + } + + rem_size = mpn_sqrt (root_ptr, rem->d, op_ptr, op_size); + + root->size = root_size; + + /* Write remainder size last, to enable us to define this function to + give only the square root remainder, if the user calles if with + ROOT == REM. */ + rem->size = rem_size; + + if (free_me != NULL) + (*_mp_free_func) (free_me, free_me_size * BYTES_PER_MP_LIMB); + + alloca (0); +} |