gcc/gmp/demos/expr/exprza.c

/* mpz expression evaluation

Copyright 2000, 2001, 2002, 2004 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 Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */

#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include "gmp.h"
#include "expr-impl.h"


/* No need to parse '-' since that's handled as an operator.
   This function also by mpq_expr_a, so it's not static.  */
size_t
mpexpr_mpz_number (mpz_ptr res, __gmp_const char *e, size_t elen, int base)
{
  char    *edup;
  size_t  i, ret;
  int     base_effective = (base == 0 ? 10 : base);
  void    *(*allocate_func) (size_t);
  void    (*free_func) (void *, size_t);

  i = 0;
  if (e[i] == '0')
    {
      i++;
      if (e[i] == 'x' || e[i] == 'b')
        i++;
    }

  for ( ; i < elen; i++)
    if (! isasciidigit_in_base (e[i], base_effective))
      break;

  mp_get_memory_functions (&allocate_func, NULL, &free_func);
  edup = (*allocate_func) (i+1);
  memcpy (edup, e, i);
  edup[i] = '\0';

  if (mpz_set_str (res, edup, base) == 0)
    ret = i;
  else
    ret = 0;

  (*free_func) (edup, i+1);
  return ret;
}

/* ignoring prec */
static void
e_mpz_init (mpz_ptr z, unsigned long prec)
{
  mpz_init (z);
}

int
mpz_expr_a (__gmp_const struct mpexpr_operator_t *table,
            mpz_ptr res, int base,
            __gmp_const char *e, size_t elen,
            mpz_srcptr var[26])
{
  struct mpexpr_parse_t  p;

  p.table = table;
  p.res = (mpX_ptr) res;
  p.base = base;
  p.e = e;
  p.elen = elen;
  p.var = (mpX_srcptr *) var;

  p.mpX_clear       = (mpexpr_fun_one_t)      mpz_clear;
  p.mpX_ulong_p     = (mpexpr_fun_i_unary_t)  mpz_fits_ulong_p;
  p.mpX_get_ui      = (mpexpr_fun_get_ui_t)   mpz_get_ui;
  p.mpX_init        = (mpexpr_fun_unary_ui_t) e_mpz_init;
  p.mpX_number      = (mpexpr_fun_number_t)   mpexpr_mpz_number;
  p.mpX_set         = (mpexpr_fun_unary_t)    mpz_set;
  p.mpX_set_or_swap = (mpexpr_fun_unary_t)    mpz_swap;
  p.mpX_set_si      = (mpexpr_fun_set_si_t)   mpz_set_si;
  p.mpX_swap        = (mpexpr_fun_swap_t)     mpz_swap;

  return mpexpr_evaluate (&p);
}