/* Error-checking, allocating wrapper for readlink.

   Copyright (C) 2017-2018 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 <scratch_buffer.h>

#include <support/check.h>

#include <support/support.h>

#include <xunistd.h>

char *

xreadlink (const char *path)

{

  struct scratch_buffer buf;

  scratch_buffer_init (&buf;;

  while (true)

    {

      ssize_t count = readlink (path, buf.data, buf.length);

      if (count < 0)

        FAIL_EXIT1 ("readlink (\"%s\"): %m", path);

      if (count < buf.length)

        {

          char *result = xstrndup (buf.data, count);

          scratch_buffer_free (&buf;;

          return result;

        }

      if (!scratch_buffer_grow (&buf))

        FAIL_EXIT1 ("scratch_buffer_grow in xreadlink");

    }

}