git.zerfleddert.de Git - proxmark3-svn/blob - client/jansson/strconv.c

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <math.h>
   6 #ifdef __MINGW32__
   7 #undef __NO_ISOCEXT /* ensure stdlib.h will declare prototypes for mingw own 'strtod' replacement, called '__strtod' */
   8 #endif
   9 #include "jansson_private.h"
  10 #include "strbuffer.h"
  11
  12 /* need jansson_private_config.h to get the correct snprintf */
  13 #ifdef HAVE_CONFIG_H
  14 #include <jansson_private_config.h>
  15 #endif
  16
  17 #ifdef __MINGW32__
  18 #define strtod __strtod
  19 #endif
  20
  21 #if JSON_HAVE_LOCALECONV
  22 #include <locale.h>
  23
  24 /*
  25   - This code assumes that the decimal separator is exactly one
  26     character.
  27
  28   - If setlocale() is called by another thread between the call to
  29     localeconv() and the call to sprintf() or strtod(), the result may
  30     be wrong. setlocale() is not thread-safe and should not be used
  31     this way. Multi-threaded programs should use uselocale() instead.
  32 */
  33
  34 static void to_locale(strbuffer_t *strbuffer)
  35 {
  36     const char *point;
  37     char *pos;
  38
  39     point = localeconv()->decimal_point;
  40     if(*point == '.') {
  41         /* No conversion needed */
  42         return;
  43     }
  44
  45     pos = strchr(strbuffer->value, '.');
  46     if(pos)
  47         *pos = *point;
  48 }
  49
  50 static void from_locale(char *buffer)
  51 {
  52     const char *point;
  53     char *pos;
  54
  55     point = localeconv()->decimal_point;
  56     if(*point == '.') {
  57         /* No conversion needed */
  58         return;
  59     }
  60
  61     pos = strchr(buffer, *point);
  62     if(pos)
  63         *pos = '.';
  64 }
  65 #endif
  66
  67 int jsonp_strtod(strbuffer_t *strbuffer, double *out)
  68 {
  69     double value;
  70     char *end;
  71
  72 #if JSON_HAVE_LOCALECONV
  73     to_locale(strbuffer);
  74 #endif
  75
  76     errno = 0;
  77     value = strtod(strbuffer->value, &end);
  78     assert(end == strbuffer->value + strbuffer->length);
  79
  80     if((value == HUGE_VAL || value == -HUGE_VAL) && errno == ERANGE) {
  81         /* Overflow */
  82         return -1;
  83     }
  84
  85     *out = value;
  86     return 0;
  87 }
  88
  89 int jsonp_dtostr(char *buffer, size_t size, double value, int precision)
  90 {
  91     int ret;
  92     char *start, *end;
  93     size_t length;
  94
  95     if (precision == 0)
  96         precision = 17;
  97
  98     ret = snprintf(buffer, size, "%.*g", precision, value);
  99     if(ret < 0)
 100         return -1;
 101
 102     length = (size_t)ret;
 103     if(length >= size)
 104         return -1;
 105
 106 #if JSON_HAVE_LOCALECONV
 107     from_locale(buffer);
 108 #endif
 109
 110     /* Make sure there's a dot or 'e' in the output. Otherwise
 111        a real is converted to an integer when decoding */
 112     if(strchr(buffer, '.') == NULL &&
 113        strchr(buffer, 'e') == NULL)
 114     {
 115         if(length + 3 >= size) {
 116             /* No space to append ".0" */
 117             return -1;
 118         }
 119         buffer[length] = '.';
 120         buffer[length + 1] = '0';
 121         buffer[length + 2] = '\0';
 122         length += 2;
 123     }
 124
 125     /* Remove leading '+' from positive exponent. Also remove leading
 126        zeros from exponents (added by some printf() implementations) */
 127     start = strchr(buffer, 'e');
 128     if(start) {
 129         start++;
 130         end = start + 1;
 131
 132         if(*start == '-')
 133             start++;
 134
 135         while(*end == '0')
 136             end++;
 137
 138         if(end != start) {
 139             memmove(start, end, length - (size_t)(end - buffer));
 140             length -= (size_t)(end - start);
 141         }
 142     }
 143
 144     return (int)length;
 145 }