source/libs/poppler/poppler-0.36.0/goo/gstrtod.cc

   1 /* This file is part of Libspectre.
   2  *
   3  * Copyright (C) 2007, 2012 Albert Astals Cid <aacid@kde.org>
   4  * Copyright (C) 2007 Carlos Garcia Campos <carlosgc@gnome.org>
   5  *
   6  * Libspectre is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * Libspectre is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  */
  20
  21 /* This function comes from spectre-utils from libspectre */
  22
  23 #include "gstrtod.h"
  24
  25 #include <locale.h>
  26 #include <errno.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #define ascii_isspace(c) \
  31   (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v')
  32 #define ascii_isdigit(c) \
  33   (c >= '0' && c <= '9')
  34
  35 double gatof(const char *nptr)
  36 {
  37   return gstrtod(nptr, NULL);
  38 }
  39
  40 double gstrtod(const char *nptr, char **endptr)
  41 {
  42   char *fail_pos;
  43   double val;
  44   struct lconv *locale_data;
  45   const char *decimal_point;
  46   int decimal_point_len;
  47   const char *p, *decimal_point_pos;
  48   const char *end = NULL; /* Silence gcc */
  49   int strtod_errno;
  50
  51   fail_pos = NULL;
  52
  53   locale_data = localeconv ();
  54   decimal_point = locale_data->decimal_point;
  55   decimal_point_len = strlen (decimal_point);
  56
  57   decimal_point_pos = NULL;
  58   end = NULL;
  59
  60   if (decimal_point[0] != '.' || decimal_point[1] != 0) {
  61     p = nptr;
  62     /* Skip leading space */
  63     while (ascii_isspace (*p))
  64       p++;
  65
  66     /* Skip leading optional sign */
  67     if (*p == '+' || *p == '-')
  68       p++;
  69
  70     if (ascii_isdigit (*p) || *p == '.') {
  71       while (ascii_isdigit (*p))
  72         p++;
  73
  74       if (*p == '.')
  75         decimal_point_pos = p++;
  76
  77       while (ascii_isdigit (*p))
  78         p++;
  79
  80       if (*p == 'e' || *p == 'E')
  81         p++;
  82       if (*p == '+' || *p == '-')
  83         p++;
  84       while (ascii_isdigit (*p))
  85         p++;
  86
  87       end = p;
  88     }
  89     /* For the other cases, we need not convert the decimal point */
  90   }
  91
  92   if (decimal_point_pos) {
  93     char *copy, *c;
  94
  95     /* We need to convert the '.' to the locale specific decimal point */
  96     copy = (char *) malloc (end - nptr + 1 + decimal_point_len);
  97
  98     c = copy;
  99     memcpy (c, nptr, decimal_point_pos - nptr);
 100     c += decimal_point_pos - nptr;
 101     memcpy (c, decimal_point, decimal_point_len);
 102     c += decimal_point_len;
 103     memcpy (c, decimal_point_pos + 1, end - (decimal_point_pos + 1));
 104     c += end - (decimal_point_pos + 1);
 105     *c = 0;
 106
 107     errno = 0;
 108     val = strtod (copy, &fail_pos);
 109     strtod_errno = errno;
 110
 111     if (fail_pos) {
 112       if (fail_pos - copy > decimal_point_pos - nptr)
 113         fail_pos = (char *)nptr + (fail_pos - copy) - (decimal_point_len - 1);
 114       else
 115         fail_pos = (char *)nptr + (fail_pos - copy);
 116     }
 117
 118     free (copy);
 119   } else if (end) {
 120     char *copy;
 121
 122     copy = (char *) malloc (end - (char *)nptr + 1);
 123     memcpy (copy, nptr, end - nptr);
 124     *(copy + (end - (char *)nptr)) = 0;
 125
 126     errno = 0;
 127     val = strtod (copy, &fail_pos);
 128     strtod_errno = errno;
 129
 130     if (fail_pos) {
 131       fail_pos = (char *)nptr + (fail_pos - copy);
 132     }
 133
 134     free (copy);
 135   } else {
 136     errno = 0;
 137     val = strtod (nptr, &fail_pos);
 138     strtod_errno = errno;
 139   }
 140
 141   if (endptr)
 142     *endptr = fail_pos;
 143
 144   errno = strtod_errno;
 145
 146   return val;
 147 }