/* A more useful interface to strtol.

   Copyright (C) 1995-1996, 1998-2001, 2003-2007, 2009-2018 Free Software

   Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

/* Written by Jim Meyering. */

#ifndef __strtol

# define __strtol strtol

# define __strtol_t long int

# define __xstrtol xstrtol

# define STRTOL_T_MINIMUM LONG_MIN

# define STRTOL_T_MAXIMUM LONG_MAX

#endif

#include <config.h>

#include "xstrtol.h"

/* Some pre-ANSI implementations (e.g. SunOS 4)

   need stderr defined if assertion checking is enabled.  */

#include <stdio.h>

#include <ctype.h>

#include <errno.h>

#include <limits.h>

#include <stdlib.h>

#include <string.h>

#include "assure.h"

#include "intprops.h"

/* xstrtoll.c and xstrtoull.c, which include this file, require that

   ULLONG_MAX, LLONG_MAX, LLONG_MIN are defined, but <limits.h> does not

   define them on all platforms.  */

#ifndef ULLONG_MAX

# define ULLONG_MAX TYPE_MAXIMUM (unsigned long long)

#endif

#ifndef LLONG_MAX

# define LLONG_MAX TYPE_MAXIMUM (long long int)

#endif

#ifndef LLONG_MIN

# define LLONG_MIN TYPE_MINIMUM (long long int)

#endif

static strtol_error

bkm_scale (__strtol_t *x, int scale_factor)

{

  if (TYPE_SIGNED (__strtol_t) && *x < STRTOL_T_MINIMUM / scale_factor)

    {

      *x = STRTOL_T_MINIMUM;

      return LONGINT_OVERFLOW;

    }

  if (STRTOL_T_MAXIMUM / scale_factor < *x)

    {

      *x = STRTOL_T_MAXIMUM;

      return LONGINT_OVERFLOW;

    }

  *x *= scale_factor;

  return LONGINT_OK;

}

static strtol_error

bkm_scale_by_power (__strtol_t *x, int base, int power)

{

  strtol_error err = LONGINT_OK;

  while (power--)

    err |= bkm_scale (x, base);

  return err;

}

/* FIXME: comment.  */

strtol_error

__xstrtol (const char *s, char **ptr, int strtol_base,

           __strtol_t *val, const char *valid_suffixes)

{

  char *t_ptr;

  char **p;

  __strtol_t tmp;

  strtol_error err = LONGINT_OK;

  assure (0 <= strtol_base && strtol_base <= 36);

  p = (ptr ? ptr : &t_ptr);

  errno = 0;

  if (! TYPE_SIGNED (__strtol_t))

    {

      const char *q = s;

      unsigned char ch = *q;

      while (isspace (ch))

        ch = *++q;

      if (ch == '-')

        return LONGINT_INVALID;

    }

  tmp = __strtol (s, p, strtol_base);

  if (*p == s)

    {

      /* If there is no number but there is a valid suffix, assume the

         number is 1.  The string is invalid otherwise.  */

      if (valid_suffixes && **p && strchr (valid_suffixes, **p))

        tmp = 1;

      else

        return LONGINT_INVALID;

    }

  else if (errno != 0)

    {

      if (errno != ERANGE)

        return LONGINT_INVALID;

      err = LONGINT_OVERFLOW;

    }

  /* Let valid_suffixes == NULL mean "allow any suffix".  */

  /* FIXME: update all callers except the ones that allow suffixes

     after the number, changing last parameter NULL to "".  */

  if (!valid_suffixes)

    {

      *val = tmp;

      return err;

    }

  if (**p != '\0')

    {

      int base = 1024;

      int suffixes = 1;

      strtol_error overflow;

      if (!strchr (valid_suffixes, **p))

        {

          *val = tmp;

          return err | LONGINT_INVALID_SUFFIX_CHAR;

        }

      switch (**p)

        {

        case 'E': case 'G': case 'g': case 'k': case 'K': case 'M': case 'm':

        case 'P': case 'T': case 't': case 'Y': case 'Z':

          /* The "valid suffix" '0' is a special flag meaning that

             an optional second suffix is allowed, which can change

             the base.  A suffix "B" (e.g. "100MB") stands for a power

             of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for

             a power of 1024.  If no suffix (e.g. "100M"), assume

             power-of-1024.  */

          if (strchr (valid_suffixes, '0'))

            switch (p[0][1])

              {

              case 'i':

                if (p[0][2] == 'B')

                  suffixes += 2;

                break;

              case 'B':

              case 'D': /* 'D' is obsolescent */

                base = 1000;

                suffixes++;

                break;

              }

        }

      switch (**p)

        {

        case 'b':

          overflow = bkm_scale (&tmp, 512);

          break;

        case 'B':

          /* This obsolescent first suffix is distinct from the 'B'

             second suffix above.  E.g., 'tar -L 1000B' means change

             the tape after writing 1000 KiB of data.  */

          overflow = bkm_scale (&tmp, 1024);

          break;

        case 'c':

          overflow = LONGINT_OK;

          break;

        case 'E': /* exa or exbi */

          overflow = bkm_scale_by_power (&tmp, base, 6);

          break;

        case 'G': /* giga or gibi */

        case 'g': /* 'g' is undocumented; for compatibility only */

          overflow = bkm_scale_by_power (&tmp, base, 3);

          break;

        case 'k': /* kilo */

        case 'K': /* kibi */

          overflow = bkm_scale_by_power (&tmp, base, 1);

          break;

        case 'M': /* mega or mebi */

        case 'm': /* 'm' is undocumented; for compatibility only */

          overflow = bkm_scale_by_power (&tmp, base, 2);

          break;

        case 'P': /* peta or pebi */

          overflow = bkm_scale_by_power (&tmp, base, 5);

          break;

        case 'T': /* tera or tebi */

        case 't': /* 't' is undocumented; for compatibility only */

          overflow = bkm_scale_by_power (&tmp, base, 4);

          break;

        case 'w':

          overflow = bkm_scale (&tmp, 2);

          break;

        case 'Y': /* yotta or 2**80 */

          overflow = bkm_scale_by_power (&tmp, base, 8);

          break;

        case 'Z': /* zetta or 2**70 */

          overflow = bkm_scale_by_power (&tmp, base, 7);

          break;

        default:

          *val = tmp;

          return err | LONGINT_INVALID_SUFFIX_CHAR;

        }

      err |= overflow;

      *p += suffixes;

      if (**p)

        err |= LONGINT_INVALID_SUFFIX_CHAR;

    }

  *val = tmp;

  return err;

}