1  /* Convert string to double, using the C locale.  -*- coding: utf-8 -*-
       2  
       3     Copyright (C) 2003-2004, 2009-2023 Free Software Foundation, Inc.
       4  
       5     This program is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU General Public License as published by
       7     the Free Software Foundation, either version 3 of the License, or
       8     (at your option) any later version.
       9  
      10     This program is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU General Public License for more details.
      14  
      15     You should have received a copy of the GNU General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #ifdef __cplusplus
      19  extern "C" {
      20  #endif
      21  
      22  /* Parse the initial portion of the string pointed to by NPTR as a floating-
      23     point number (in decimal or hexadecimal notation), like in the C locale:
      24     accepting only the ASCII digits '0'..'9', and only '.' as decimal point
      25     character.
      26     If ENDPTR is not NULL, set *ENDPTR to point to the first byte beyond the
      27     parsed number or to NPTR if the string does not start with a parsable
      28     number.
      29     Return value:
      30     - If successful, return the value as a double or 'long double',
      31       respectively, and don't modify errno.
      32     - In case of overflow, return ±HUGE_VAL or ±HUGE_VALL, respectively, and
      33       set errno to ERANGE.
      34     - In case of underflow, return a value very near to 0 and set errno to
      35       ERANGE.
      36     - If the string does not start with a number at all, return 0 (and recall
      37       that if ENDPTR != NULL, *ENDPTR is set to NPTR), and maybe set errno to
      38       EINVAL.
      39     - In case of other error, return 0 and set errno, for example to ENOMEM.  */
      40  extern double      c_strtod  (char const *nptr, char **endptr);
      41  extern long double c_strtold (char const *nptr, char **endptr);
      42  
      43  #ifdef __cplusplus
      44  }
      45  #endif