strtol.h

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#ifndef __STRTOL_H__
#define __STRTOL_H__

#include <nlibc.h>

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>

//---------------------------------------------------------------------------------------------
#ifndef __HAS_MAIN
extern long strtol(const char *nptr, char **endptr, int base);
#else
#if !defined(__cflow_processed) || defined(_uses_strtol_strtol_h)
long strtol(const char *nptr, char **endptr, int base)
{
        const char *s;
        long acc, cutoff;
        int c;
        int neg, any_consumed, cutlim;
        int len;

        assert(nptr != NULL);
        /* endptr may be NULL */

        /*
         * expand compacted string to char array for easy 
         * handling
         */
        len = strlen( nptr );
        s = stringexpand( nptr, len );

        /*
         * Skip white space and pick up leading +/- sign if any.
         * If base is 0, allow 0x for hex and 0 for octal, else
         * assume decimal; if base is already 16, allow 0x.
         */
        do {
                c = (unsigned char) *s++;
        } while (isspace(c));
        if (c == '-') {
                neg = 1;
                c = *s++;
        } else {
                neg = 0;
                if (c == '+')
                        c = *s++;
        }
        if ((base == 0 || base == 16) &&
            c == '0' && (*s == 'x' || *s == 'X')) {
                c = s[1];
                s += 2;
                base = 16;
        }
        if (base == 0)
                base = c == '0' ? 8 : 10;

        /*
         * Compute the cutoff value between legal numbers and illegal
         * numbers.  That is the largest legal value, divided by the
         * base.  An input number that is greater than this value, if
         * followed by a legal input character, is too big.  One that
         * is equal to this value may be valid or not; the limit
         * between valid and invalid numbers is then based on the last
         * digit.  For instance, if the range for longs is
         * [-2147483648..2147483647] and the input base is 10,
         * cutoff will be set to 214748364 and cutlim to either
         * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
         * a value > 214748364, or equal but the next digit is > 7 (or 8),
         * the number is too big, and we will return a range error.
         *
         * Set any_consumed if any `digits' consumed; make it negative to indicate
         * overflow.
         */
        cutoff = neg ? LONG_MIN : LONG_MAX;
        cutlim = (int)(cutoff % base);
        cutoff /= base;
        if (neg) {
                if (cutlim > 0) {
                        cutlim -= base;
                        cutoff += 1;
                }
                cutlim = -cutlim;
        }
        for (acc = 0, any_consumed = 0;; c = (unsigned char) *s++) {
                if (isdigit(c))
                        c -= '0';
                else if (isalpha(c))
                        c -= isupper(c) ? 'A' - 10 : 'a' - 10;
                else
                        break;
                if (c >= base)
                        break;
                if (any_consumed < 0)
                        continue;
                if (neg) {
                        if (acc < cutoff || (acc == cutoff && c > cutlim)) {
                                any_consumed = -1;
                                acc = LONG_MIN;
                                errno = ERANGE;
                        } else {
                                any_consumed = 1;
                                acc *= base;
                                acc -= c;
                        }
                } else {
                        if (acc > cutoff || (acc == cutoff && c > cutlim)) {
                                any_consumed = -1;
                                acc = LONG_MAX;
                                errno = ERANGE;
                        } else {
                                any_consumed = 1;
                                acc *= base;
                                acc += c;
                        }
                }
        }
        if (endptr != 0)
                /* LINTED interface specification */
                *endptr = (char *)(any_consumed ? s - 1 : nptr);
        return (acc);
}
#endif // _uses_strtol_strtol_h
#endif // Has Main

#define strtoll(nptr, endptr, base)  strtol(nptr, endptr, base)

#endif // __STRTOL_H__

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