| /* xtom -- convert a hexadecimal string to a MINT, and return a pointer to |
| the MINT. |
| |
| Copyright 1991, 1994, 1995, 1996, 2000, 2001, 2002, 2005 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 <string.h> |
| #include <ctype.h> |
| #include "mp.h" |
| #include "gmp.h" |
| #include "gmp-impl.h" |
| |
| extern const unsigned char __gmp_digit_value_tab[]; |
| #define digit_value __gmp_digit_value_tab |
| |
| MINT * |
| xtom (const char *str) |
| { |
| size_t str_size; |
| char *s, *begs; |
| size_t i; |
| mp_size_t xsize; |
| int c; |
| int negative; |
| MINT *x = (MINT *) (*__gmp_allocate_func) (sizeof (MINT)); |
| TMP_DECL; |
| |
| /* Skip whitespace. */ |
| do |
| c = (unsigned char) *str++; |
| while (isspace (c)); |
| |
| negative = 0; |
| if (c == '-') |
| { |
| negative = 1; |
| c = (unsigned char) *str++; |
| } |
| |
| if (digit_value[c] >= 16) |
| return 0; /* error if no digits */ |
| |
| TMP_MARK; |
| str_size = strlen (str - 1); |
| s = begs = (char *) TMP_ALLOC (str_size + 1); |
| |
| for (i = 0; i < str_size; i++) |
| { |
| if (!isspace (c)) |
| { |
| int dig = digit_value[c]; |
| if (dig >= 16) |
| { |
| TMP_FREE; |
| return 0; |
| } |
| *s++ = dig; |
| } |
| c = (unsigned char) *str++; |
| } |
| |
| str_size = s - begs; |
| |
| xsize = str_size / __mp_bases[16].chars_per_limb + 1; |
| x->_mp_alloc = xsize; |
| x->_mp_d = (mp_ptr) (*__gmp_allocate_func) (xsize * BYTES_PER_MP_LIMB); |
| |
| xsize = mpn_set_str (x->_mp_d, (unsigned char *) begs, str_size, 16); |
| x->_mp_size = negative ? -xsize : xsize; |
| |
| TMP_FREE; |
| return x; |
| } |