root/usr/src/common/util/strtoll.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#if     defined(_KERNEL)
#include <sys/null.h>
#endif  /* _KERNEL */

#if     defined(_KERNEL) && !defined(_BOOT)
#include <sys/errno.h>
#else   /* _KERNEL && !_BOOT */
#if     !defined(_BOOT) && !defined(_KMDB) && !defined(_STANDALONE)
#include "lint.h"
#endif  /* !_BOOT && !_KMDB && !_STANDALONE */
#if     defined(_STANDALONE)
#include <sys/cdefs.h>
#include <stand.h>
#include <limits.h>

typedef long long longlong_t;
#else
#include <errno.h>
#include <ctype.h>
#include <limits.h>
#include <stdlib.h>
#endif  /* _STANDALONE */
#endif  /* _KERNEL && !_BOOT */
#include "strtolctype.h"
#include <sys/types.h>

#if     defined(_KERNEL) && !defined(_BOOT)
int
ddi_strtoll(const char *str, char **nptr, int base, longlong_t *result)
#else   /* _KERNEL && !_BOOT */
longlong_t
strtoll(const char *str, char **nptr, int base)
#endif  /* _KERNEL && !_BOOT */
{
        longlong_t val;
        int c;
        int xx;
        int neg = 0;
        longlong_t multmin;
        longlong_t limit;
        const char **ptr = (const char **)nptr;
        const unsigned char *ustr = (const unsigned char *)str;

        if (ptr != NULL)
                *ptr = (char *)ustr; /* in case no number is formed */
        if (base < 0 || base > MBASE || base == 1) {
                /* base is invalid -- should be a fatal error */
#if     defined(_KERNEL) && !defined(_BOOT)
                return (EINVAL);
#else   /* _KERNEL && !_BOOT */
                errno = EINVAL;
                return (0);
#endif  /* _KERNEL && !_BOOT */
        }
        if (!isalnum(c = *ustr)) {
                while (isspace(c))
                        c = *++ustr;
                switch (c) {
                case '-':
                        neg++;
                        /* FALLTHROUGH */
                case '+':
                        c = *++ustr;
                }
        }
        if (base == 0) {
                if (c != '0')
                        base = 10;
                else if (ustr[1] == 'x' || ustr[1] == 'X')
                        base = 16;
                else
                        base = 8;
        }
        /*
         * for any base > 10, the digits incrementally following
         *      9 are assumed to be "abc...z" or "ABC...Z"
         */
        if (!lisalnum(c) || (xx = DIGIT(c)) >= base) {
                /* no number formed */
#if     defined(_KERNEL) && !defined(_BOOT)
                return (EINVAL);
#else   /* _KERNEL && !_BOOT */
                return (0);
#endif  /* _KERNEL && !_BOOT */
        }
        if (base == 16 && c == '0' && (ustr[1] == 'x' || ustr[1] == 'X') &&
            isxdigit(ustr[2]))
                c = *(ustr += 2); /* skip over leading "0x" or "0X" */

        /* this code assumes that abs(LLONG_MIN) >= abs(LLONG_MAX) */
        if (neg)
                limit = LLONG_MIN;
        else
                limit = -LLONG_MAX;
        multmin = limit / (longlong_t)base;
        val = -DIGIT(c);
        for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; ) {
                /* accumulate neg avoids surprises near LLONG_MAX */
                if (val < multmin)
                        goto overflow;
                val *= base;
                if (val < limit + xx)
                        goto overflow;
                val -= xx;
                c = *++ustr;
        }
        if (ptr != NULL)
                *ptr = (char *)ustr;
#if     defined(_KERNEL) && !defined(_BOOT)
        *result = neg ? val : -val;
        return (0);
#else   /* _KERNEL && !_BOOT */
        return (neg ? val : -val);
#endif  /* _KERNEL && !_BOOT */

overflow:
        for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; (c = *++ustr))
                ;
        if (ptr != NULL)
                *ptr = (char *)ustr;
#if     defined(_KERNEL) && !defined(_BOOT)
        return (ERANGE);
#else   /* _KERNEL && !_BOOT */
        errno = ERANGE;
        return (neg ? LLONG_MIN : LLONG_MAX);
#endif  /* _KERNEL && !_BOOT */
}