1 /* mpf_fits_s*_p -- test whether an mpf fits a C signed type. 2 3 Copyright 2001, 2002 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library. 6 7 The GNU MP Library is free software; you can redistribute it and/or modify 8 it under the terms of the GNU Lesser General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or (at your 10 option) any later version. 11 12 The GNU MP Library is distributed in the hope that it will be useful, but 13 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 15 License for more details. 16 17 You should have received a copy of the GNU Lesser General Public License 18 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 19 20 #include "gmp.h" 21 #include "gmp-impl.h" 22 23 24 /* Notice this is equivalent to mpz_set_f + mpz_fits_s*_p. */ 25 26 int 27 FUNCTION (mpf_srcptr f) __GMP_NOTHROW 28 { 29 mp_size_t fs, fn; 30 mp_srcptr fp; 31 mp_exp_t exp; 32 mp_limb_t fl; 33 34 fs = SIZ(f); 35 if (fs == 0) 36 return 1; /* zero fits */ 37 38 exp = EXP(f); 39 if (exp < 1) 40 return 1; /* -1 < f < 1 truncates to zero, so fits */ 41 42 fp = PTR(f); 43 fn = ABS (fs); 44 45 if (exp == 1) 46 { 47 fl = fp[fn-1]; 48 } 49 #if GMP_NAIL_BITS != 0 50 else if (exp == 2 && MAXIMUM > GMP_NUMB_MAX) 51 { 52 fl = fp[fn-1]; 53 if ((fl >> GMP_NAIL_BITS) != 0) 54 return 0; 55 fl = (fl << GMP_NUMB_BITS); 56 if (fn >= 2) 57 fl |= fp[fn-2]; 58 } 59 #endif 60 else 61 return 0; 62 63 return fl <= (fs >= 0 ? (mp_limb_t) MAXIMUM : - (mp_limb_t) MINIMUM); 64 } 65