/* Estimate the length of the string generated by a vprintf-like

   function.  Used by vasprintf and xvasprintf.

   Copyright (C) 1994-2026 Free Software Foundation, Inc.

This file is part of the libiberty library.

Libiberty is free software; you can redistribute it and/or

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 of the License, or (at your option) any later version.

Libiberty 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

Library General Public License for more details.

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

License along with libiberty; see the file COPYING.LIB.  If not, write

to the Free Software Foundation, Inc., 51 Franklin Street - Fifth

Floor, Boston, MA 02110-1301, USA.  */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <ansidecl.h>

#include <stdarg.h>

#if !defined (va_copy) && defined (__va_copy)

# define va_copy(d,s)  __va_copy((d),(s))

#endif

#include <stdio.h>

#include <errno.h>

#ifdef HAVE_STRING_H

#include <string.h>

#endif

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#else

extern unsigned long strtoul ();

#endif

#include "libiberty.h"

static inline unsigned long

do_strtoul (const char *str, char **endptr, int base)

  {

#ifdef _WIN32

    /* The MSVCRT `strtoul()` function resets `errno` to zero upon success.

       We must preserve it across this call.  */

    int saved_errno = errno;

#endif

    long value = strtoul (str, endptr, base);

#ifdef _WIN32

    errno = saved_errno;

#endif

    return value;

  }

int

libiberty_vprintf_buffer_size (const char *format, va_list args)

{

  const char *p = format;

  /* Add one to make sure that it is never zero, which might cause malloc

     to return NULL.  */

  int total_width = strlen (format) + 1;

  va_list ap;

#ifdef va_copy

  va_copy (ap, args);

#else

  memcpy ((void *) &ap, (void *) &args, sizeof (va_list));

#endif

  while (*p != '\0')

    {

      if (*p++ == '%')

  {

    int prec = 0;

    while (strchr ("-+ #0", *p))

      ++p;

    if (*p == '*')

      {

        ++p;

        total_width += abs (va_arg (ap, int));

      }

    else

      total_width += do_strtoul (p, (char **) &p, 10);

    if (*p == '.')

      {

        ++p;

        if (*p == '*')

    {

      ++p;

      total_width += abs (va_arg (ap, int));

    }

        else

    total_width += do_strtoul (p, (char **) &p, 10);

      }

    do

      {

        switch (*p)

    {

    case 'h':

      ++p;

      continue;

    case 'l':

    case 'L':

      ++prec;

      ++p;

      continue;

    case 'z':

      prec = 3;

      ++p;

      continue;

    case 't':

      prec = 4;

      ++p;

      continue;

#ifdef _WIN32

    case 'I':

      if (p[1] == '6' && p[2] == '4')

        {

          prec = 2;

          p += 3;

          continue;

        }

      break;

#endif

    default:

      break;

    }

        break;

      }

    while (1);

    /* Should be big enough for any format specifier except %s and floats.  */

    total_width += 30;

    switch (*p)

      {

      case 'd':

      case 'i':

      case 'o':

      case 'u':

      case 'x':

      case 'X':

        switch (prec)

    {

    case 0: (void) va_arg (ap, int); break;

    case 1: (void) va_arg (ap, long int); break;

    case 2: (void) va_arg (ap, long long int); break;

    case 3: (void) va_arg (ap, size_t); break;

    case 4: (void) va_arg (ap, ptrdiff_t); break;

    }

        break;

      case 'c':

        (void) va_arg (ap, int);

        break;

      case 'f':

      case 'e':

      case 'E':

      case 'g':

      case 'G':

        if (!prec)

    {

      (void) va_arg (ap, double);

      /* Since an ieee double can have an exponent of 308, we'll

         make the buffer wide enough to cover the gross case. */

      total_width += 308;

    }

        else

    {

      (void) va_arg (ap, long double);

      total_width += 4932;

    }

        break;

      case 's':

        total_width += strlen (va_arg (ap, char *));

        break;

      case 'p':

      case 'n':

        (void) va_arg (ap, char *);

        break;

      }

    p++;

  }

    }

#ifdef va_copy

  va_end (ap);

#endif

  return total_width;

}