/* Copyright (C) 1995-2018 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/>.  */

#include "libioP.h"

#include "strfile.h"

#include <stdio.h>

#include <stdlib.h>

struct _IO_FILE_memstream

{

  _IO_strfile _sf;

  char **bufloc;

  size_t *sizeloc;

};

static int _IO_mem_sync (FILE* fp) __THROW;

static void _IO_mem_finish (FILE* fp, int) __THROW;

static const struct _IO_jump_t _IO_mem_jumps libio_vtable =

{

  JUMP_INIT_DUMMY,

  JUMP_INIT (finish, _IO_mem_finish),

  JUMP_INIT (overflow, _IO_str_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_mem_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)

};

/* Open a stream that writes into a malloc'd buffer that is expanded as

   necessary.  *BUFLOC and *SIZELOC are updated with the buffer's location

   and the number of characters written on fflush or fclose.  */

FILE *

__open_memstream (char **bufloc, size_t *sizeloc)

{

  struct locked_FILE

  {

    struct _IO_FILE_memstream fp;

#ifdef _IO_MTSAFE_IO

    _IO_lock_t lock;

#endif

    struct _IO_wide_data wd;

  } *new_f;

  char *buf;

  new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));

  if (new_f == NULL)

    return NULL;

#ifdef _IO_MTSAFE_IO

  new_f->fp._sf._sbf._f._lock = &new_f->lock;

#endif

  buf = calloc (1, BUFSIZ);

  if (buf == NULL)

    {

      free (new_f);

      return NULL;

    }

  _IO_init_internal (&new_f->fp._sf._sbf._f, 0);

  _IO_JUMPS_FILE_plus (&new_f->fp._sf._sbf) = &_IO_mem_jumps;

  _IO_str_init_static_internal (&new_f->fp._sf, buf, BUFSIZ, buf);

  new_f->fp._sf._sbf._f._flags &= ~_IO_USER_BUF;

  new_f->fp._sf._s._allocate_buffer_unused = (_IO_alloc_type) malloc;

  new_f->fp._sf._s._free_buffer_unused = (_IO_free_type) free;

  new_f->fp.bufloc = bufloc;

  new_f->fp.sizeloc = sizeloc;

  /* Disable single thread optimization.  BZ 21735.  */

  new_f->fp._sf._sbf._f._flags2 |= _IO_FLAGS2_NEED_LOCK;

  return (FILE *) &new_f->fp._sf._sbf;

}

libc_hidden_def (__open_memstream)

weak_alias (__open_memstream, open_memstream)

static int

_IO_mem_sync (FILE *fp)

{

  struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;

  if (fp->_IO_write_ptr == fp->_IO_write_end)

    {

      _IO_str_overflow (fp, '\0');

      --fp->_IO_write_ptr;

    }

  *mp->bufloc = fp->_IO_write_base;

  *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;

  return 0;

}

static void

_IO_mem_finish (FILE *fp, int dummy)

{

  struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;

  *mp->bufloc = (char *) realloc (fp->_IO_write_base,

				  fp->_IO_write_ptr - fp->_IO_write_base + 1);

  if (*mp->bufloc != NULL)

    {

      (*mp->bufloc)[fp->_IO_write_ptr - fp->_IO_write_base] = '\0';

      *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;

      fp->_IO_buf_base = NULL;

    }

  _IO_str_finish (fp, 0);

}