/*-
* Copyright (c) 2014 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. [rescinded 22 July 1999]
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

/*

@deftypefn Supplemental {long long int} strtoll (const char *@var{string}, @
 char **@var{endptr}, int @var{base})
@deftypefnx Supplemental {unsigned long long int} strtoul (@
 const char *@var{string}, char **@var{endptr}, int @var{base})

The @code{strtoll} function converts the string in @var{string} to a
long long integer value according to the given @var{base}, which must be
between 2 and 36 inclusive, or be the special value 0.  If @var{base}
is 0, @code{strtoll} will look for the prefixes @code{0} and @code{0x}
to indicate bases 8 and 16, respectively, else default to base 10.
When the base is 16 (either explicitly or implicitly), a prefix of
@code{0x} is allowed.  The handling of @var{endptr} is as that of
@code{strtod} above.  The @code{strtoull} function is the same, except
that the converted value is unsigned.

@end deftypefn

*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <errno.h>
#ifdef NEED_DECLARATION_ERRNO
extern int errno;
#endif
#include "safe-ctype.h"

#ifdef HAVE_LONG_LONG

__extension__
typedef unsigned long long ullong_type;

__extension__
typedef long long llong_type;

/* FIXME: It'd be nice to configure around these, but the include files are too
  painful.  These macros should at least be more portable than hardwired hex
  constants. */

#ifndef ULLONG_MAX
#define ULLONG_MAX (~(ullong_type)0) /* 0xFFFFFFFFFFFFFFFF */
#endif

#ifndef LLONG_MAX
#define LLONG_MAX ((llong_type)(ULLONG_MAX >> 1)) /* 0x7FFFFFFFFFFFFFFF */
#endif

#ifndef LLONG_MIN
#define LLONG_MIN (~LLONG_MAX) /* 0x8000000000000000 */
#endif

/*
* Convert a string to a long long integer.
*
* Ignores `locale' stuff.  Assumes that the upper and lower case
* alphabets and digits are each contiguous.
*/
llong_type
strtoll(const char *nptr, char **endptr, register int base)
{
       register const char *s = nptr;
       register ullong_type acc;
       register int c;
       register ullong_type cutoff;
       register int neg = 0, any, cutlim;

       /*
        * 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 = *s++;
       } while (ISSPACE(c));
       if (c == '-') {
               neg = 1;
               c = *s++;
       } else 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 if any `digits' consumed; make it negative to indicate
        * overflow.
        */
       cutoff = neg ? -(ullong_type)LLONG_MIN : LLONG_MAX;
       cutlim = cutoff % (ullong_type)base;
       cutoff /= (ullong_type)base;
       for (acc = 0, any = 0;; c = *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 < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
                       any = -1;
               else {
                       any = 1;
                       acc *= base;
                       acc += c;
               }
       }
       if (any < 0) {
               acc = neg ? LLONG_MIN : LLONG_MAX;
               errno = ERANGE;
       } else if (neg)
               acc = -acc;
       if (endptr != 0)
               *endptr = (char *) (any ? s - 1 : nptr);
       return (acc);
}

#endif /* ifdef HAVE_LONG_LONG */