kolibrios/programs/develop/libraries/kolibri-libc/source/stdlib/strtol.c
turbocat 728f124678 Added git source kolibri-libc and
Configured autobuild

git-svn-id: svn://kolibrios.org@8687 a494cfbc-eb01-0410-851d-a64ba20cac60
2021-04-27 16:33:31 +00:00

79 lines
1.2 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#define LONG_MIN (-2147483647L-1)
#define LONG_MAX (2147483647L)
#define ULONG_MAX (4294967295UL)
int getdigit(char ch, int base)
{
if (isdigit(ch)) ch-= '0';
else
if (isalpha(ch) && ch <= 'Z') ch = 10 + ch - 'A';
else
if (isalpha(ch)) ch = 10 + ch - 'a';
else
return -1;
if (ch / base != 0) return -1;
return ch;
}
long int strtol (const char* str, char** endptr, int base)
{
long int res = 0;
int sign = 1;
if (base > 36)
{
errno = EINVAL;
goto bye;
}
while (isspace(*str)) str++;
if (*str == '-') { sign = -1; str++; }
else
if (*str == '+') str++;
if (base == 0 || base == 16)
{
if (*str == '0' && (str[1] == 'x' || str[1] == 'X'))
{
base = 16;
str += 2;
}
}
if (base == 0 && *str == '0') base = 8;
if (base == 0) base = 10;
int digit;
while ((digit = getdigit(*str, base)) >= 0)
{
res = base * res + digit;
str++;
if (res < 0)
{
errno = ERANGE;
if (sign > 0)
res = LONG_MAX;
else
res = LONG_MIN;
}
}
bye:
if (endptr)
*endptr = (char*)str;
return res * sign;
}