reactos/lib/sdk/crt/string/strtoi64.c

   1 #include <precomp.h>
   2
   3
   4 __int64
   5 _strtoi64(const char *nptr, char **endptr, int base)
   6 {
   7     BOOL negative = FALSE;
   8     __int64 ret = 0;
   9
  10    while(isspace((unsigned char)*nptr)) nptr++;
  11
  12     if(*nptr == '-') {
  13         negative = TRUE;
  14         nptr++;
  15     } else if(*nptr == '+')
  16         nptr++;
  17
  18     if((base==0 || base==16) && *nptr=='0' && tolower(*(nptr+1))=='x') {
  19         base = 16;
  20         nptr += 2;
  21     }
  22
  23     if(base == 0) {
  24         if(*nptr=='0')
  25             base = 8;
  26         else
  27             base = 10;
  28     }
  29
  30     while(*nptr) {
  31         char cur = tolower(*nptr);
  32         int v;
  33
  34         if(isdigit((unsigned char)cur)) {
  35             if(cur >= '0'+base)
  36                 break;
  37             v = cur-'0';
  38         } else {
  39             if(cur<'a' || cur>='a'+base-10)
  40                 break;
  41             v = cur-'a'+10;
  42         }
  43
  44         if(negative)
  45             v = -v;
  46
  47         nptr++;
  48
  49         if(!negative && (ret>_I64_MAX/base || ret*base>_I64_MAX-v)) {
  50             ret = _I64_MAX;
  51             *_errno() = ERANGE;
  52         } else if(negative && (ret<_I64_MIN/base || ret*base<_I64_MIN-v)) {
  53             ret = _I64_MIN;
  54             *_errno() = ERANGE;
  55         } else
  56             ret = ret*base + v;
  57     }
  58
  59     if(endptr)
  60         *endptr = (char*)nptr;
  61
  62     return ret;
  63 }
  64
  65
  66 /* EOF */