contrib/gmp/errno.c

   1 /* gmp_errno, __gmp_exception -- exception handling and reporting.
   2
   3    THE FUNCTIONS IN THIS FILE, APART FROM gmp_errno, ARE FOR INTERNAL USE
   4    ONLY.  THEY'RE ALMOST CERTAIN TO BE SUBJECT TO INCOMPATIBLE CHANGES OR
   5    DISAPPEAR COMPLETELY IN FUTURE GNU MP RELEASES.
   6
   7 Copyright 2000, 2001, 2003 Free Software Foundation, Inc.
   8
   9 This file is part of the GNU MP Library.
  10
  11 The GNU MP Library is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU Lesser General Public License as published by
  13 the Free Software Foundation; either version 3 of the License, or (at your
  14 option) any later version.
  15
  16 The GNU MP Library is distributed in the hope that it will be useful, but
  17 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  18 or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  19 License for more details.
  20
  21 You should have received a copy of the GNU Lesser General Public License
  22 along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
  23
  24 #include <stdlib.h>
  25 #include "gmp.h"
  26 #include "gmp-impl.h"
  27
  28 int gmp_errno = 0;
  29
  30
  31 /* The deliberate divide by zero triggers an exception on most systems.  On
  32    those where it doesn't, for example power and powerpc, use abort instead.
  33
  34    Enhancement: Perhaps raise(SIGFPE) (or the same with kill()) would be
  35    better than abort.  Perhaps it'd be possible to get the BSD style
  36    FPE_INTDIV_TRAP parameter in there too.  */
  37
  38 void
  39 __gmp_exception (int error_bit)
  40 {
  41   gmp_errno |= error_bit;
  42   __gmp_junk = 10 / __gmp_0;
  43   abort ();
  44 }
  45
  46
  47 /* These functions minimize the amount of code required in functions raising
  48    exceptions.  Since they're "noreturn" and don't take any parameters, a
  49    test and call might even come out as a simple conditional jump.  */
  50 void
  51 __gmp_sqrt_of_negative (void)
  52 {
  53   __gmp_exception (GMP_ERROR_SQRT_OF_NEGATIVE);
  54 }
  55 void
  56 __gmp_divide_by_zero (void)
  57 {
  58   __gmp_exception (GMP_ERROR_DIVISION_BY_ZERO);
  59 }