/* Copyright (C) 1994-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

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

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.

   As a special exception, if you link the code in this file with

   files compiled with a GNU compiler to produce an executable,

   that does not cause the resulting executable to be covered by

   the GNU Lesser General Public License.  This exception does not

   however invalidate any other reasons why the executable file

   might be covered by the GNU Lesser General Public License.

   This exception applies to code released by its copyright holders

   in files containing the exception.  */

#include "libioP.h"

#include "strfile.h"

static int _IO_strn_overflow (FILE *fp, int c) __THROW;

static int

_IO_strn_overflow (FILE *fp, int c)

{

  /* When we come to here this means the user supplied buffer is

     filled.  But since we must return the number of characters which

     would have been written in total we must provide a buffer for

     further use.  We can do this by writing on and on in the overflow

     buffer in the _IO_strnfile structure.  */

  _IO_strnfile *snf = (_IO_strnfile *) fp;

  if (fp->_IO_buf_base != snf->overflow_buf)

    {

      /* Terminate the string.  We know that there is room for at

	 least one more character since we initialized the stream with

	 a size to make this possible.  */

      *fp->_IO_write_ptr = '\0';

      _IO_setb (fp, snf->overflow_buf,

		snf->overflow_buf + sizeof (snf->overflow_buf), 0);

      fp->_IO_write_base = snf->overflow_buf;

      fp->_IO_read_base = snf->overflow_buf;

      fp->_IO_read_ptr = snf->overflow_buf;

      fp->_IO_read_end = snf->overflow_buf + sizeof (snf->overflow_buf);

    }

  fp->_IO_write_ptr = snf->overflow_buf;

  fp->_IO_write_end = snf->overflow_buf;

  /* Since we are not really interested in storing the characters

     which do not fit in the buffer we simply ignore it.  */

  return c;

}

const struct _IO_jump_t _IO_strn_jumps libio_vtable attribute_hidden =

{

  JUMP_INIT_DUMMY,

  JUMP_INIT(finish, _IO_str_finish),

  JUMP_INIT(overflow, _IO_strn_overflow),

  JUMP_INIT(underflow, _IO_str_underflow),

  JUMP_INIT(uflow, _IO_default_uflow),

  JUMP_INIT(pbackfail, _IO_str_pbackfail),

  JUMP_INIT(xsputn, _IO_default_xsputn),

  JUMP_INIT(xsgetn, _IO_default_xsgetn),

  JUMP_INIT(seekoff, _IO_str_seekoff),

  JUMP_INIT(seekpos, _IO_default_seekpos),

  JUMP_INIT(setbuf, _IO_default_setbuf),

  JUMP_INIT(sync, _IO_default_sync),

  JUMP_INIT(doallocate, _IO_default_doallocate),

  JUMP_INIT(read, _IO_default_read),

  JUMP_INIT(write, _IO_default_write),

  JUMP_INIT(seek, _IO_default_seek),

  JUMP_INIT(close, _IO_default_close),

  JUMP_INIT(stat, _IO_default_stat),

  JUMP_INIT(showmanyc, _IO_default_showmanyc),

  JUMP_INIT(imbue, _IO_default_imbue)

};

int

_IO_vsnprintf (char *string, size_t maxlen, const char *format,

	       va_list args)

{

  _IO_strnfile sf;

  int ret;

#ifdef _IO_MTSAFE_IO

  sf.f._sbf._f._lock = NULL;

#endif

  /* We need to handle the special case where MAXLEN is 0.  Use the

     overflow buffer right from the start.  */

  if (maxlen == 0)

    {

      string = sf.overflow_buf;

      maxlen = sizeof (sf.overflow_buf);

    }

  _IO_no_init (&sf.f._sbf._f, _IO_USER_LOCK, -1, NULL, NULL);

  _IO_JUMPS (&sf.f._sbf) = &_IO_strn_jumps;

  string[0] = '\0';

  _IO_str_init_static_internal (&sf.f, string, maxlen - 1, string);

  ret = _IO_vfprintf (&sf.f._sbf._f, format, args);

  if (sf.f._sbf._f._IO_buf_base != sf.overflow_buf)

    *sf.f._sbf._f._IO_write_ptr = '\0';

  return ret;

}

ldbl_weak_alias (_IO_vsnprintf, __vsnprintf)

ldbl_weak_alias (_IO_vsnprintf, vsnprintf)