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/* Formatted output to a stream.
   Copyright (C) 2004, 2006-2017 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or
   modify it under the terms of either:

     * the GNU Lesser General Public License as published by the Free
       Software Foundation; either version 3 of the License, or (at your
       option) any later version.

   or

     * the GNU General Public License as published by the Free
       Software Foundation; either version 2 of the License, or (at your
       option) any later version.

   or both in parallel, as here.
   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/>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

/* Specification.  */
#include "unistdio.h"

#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>

#include "fseterr.h"

/* Print formatted output to the stream FP.
   Return string length of formatted string.  On error, return a negative
   value.  */
int
ulc_fprintf (FILE *fp, const char *format, ...)
{
  char buf[2000];
  char *output;
  size_t len;
  size_t lenbuf = sizeof (buf);
  va_list args;

  va_start (args, format);
  output = ulc_vasnprintf (buf, &lenbuf, format, args);
  len = lenbuf;
  va_end (args);

  if (!output)
    {
      fseterr (fp);
      return -1;
    }

  if (fwrite (output, 1, len, fp) < len)
    {
      if (output != buf)
        {
          int saved_errno = errno;
          free (output);
          errno = saved_errno;
        }
      return -1;
    }

  if (len > INT_MAX)
    {
      errno = EOVERFLOW;
      fseterr (fp);
      return -1;
    }

  return len;
}