1/* mpz_divexact_ui -- exact division mpz by ulong. 2 3Copyright 2001, 2002 Free Software Foundation, Inc. 4 5This file is part of the GNU MP Library. 6 7The GNU MP Library is free software; you can redistribute it and/or modify 8it under the terms of the GNU Lesser General Public License as published by 9the Free Software Foundation; either version 3 of the License, or (at your 10option) any later version. 11 12The GNU MP Library is distributed in the hope that it will be useful, but 13WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 15License for more details. 16 17You should have received a copy of the GNU Lesser General Public License 18along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 19 20#include "gmp.h" 21#include "gmp-impl.h" 22 23void 24mpz_divexact_ui (mpz_ptr dst, mpz_srcptr src, unsigned long divisor) 25{ 26 mp_size_t size, abs_size; 27 mp_ptr dst_ptr; 28 29 if (divisor == 0) 30 DIVIDE_BY_ZERO; 31 32 /* For nails don't try to be clever if d is bigger than a limb, just fake 33 up an mpz_t and go to the main mpz_divexact. */ 34 if (divisor > GMP_NUMB_MAX) 35 { 36 mp_limb_t dlimbs[2]; 37 mpz_t dz; 38 ALLOC(dz) = 2; 39 PTR(dz) = dlimbs; 40 mpz_set_ui (dz, divisor); 41 mpz_divexact (dst, src, dz); 42 return; 43 } 44 45 size = SIZ(src); 46 if (size == 0) 47 { 48 SIZ(dst) = 0; 49 return; 50 } 51 abs_size = ABS (size); 52 53 MPZ_REALLOC (dst, abs_size); 54 dst_ptr = PTR(dst); 55 56 MPN_DIVREM_OR_DIVEXACT_1 (dst_ptr, PTR(src), abs_size, (mp_limb_t) divisor); 57 abs_size -= (dst_ptr[abs_size-1] == 0); 58 SIZ(dst) = (size >= 0 ? abs_size : -abs_size); 59} 60