reactos/lib/sdk/crt/string/atoi64.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS system libraries
   4  * FILE:        lib/crt/??????
   5  * PURPOSE:     Unknown
   6  * PROGRAMER:   Unknown
   7  * UPDATE HISTORY:
   8  *              25/11/05: Added license header
   9  */
  10
  11 #include <precomp.h>
  12
  13 /*
  14  * @implemented
  15  */
  16 __int64
  17 CDECL
  18 _atoi64(const char *nptr)
  19 {
  20   char *s = (char *)nptr;
  21   __int64 acc = 0;
  22   int neg = 0;
  23
  24   if (nptr == NULL)
  25     return 0;
  26
  27   while(isspace((int)*s))
  28     s++;
  29   if (*s == '-')
  30     {
  31       neg = 1;
  32       s++;
  33     }
  34   else if (*s == '+')
  35     s++;
  36
  37   while (isdigit((int)*s))
  38     {
  39       acc = 10 * acc + ((int)*s - '0');
  40       s++;
  41     }
  42
  43   if (neg)
  44     acc *= -1;
  45   return acc;
  46 }