/* Copyright (C) 2015-2018 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 <nss.h>

#include <string.h>

/* Rewrite VALUE to a valid field value in the NSS database.  Invalid

   characters are replaced with a single space character ' '.  If

   VALUE is NULL, the empty string is returned.  *TO_BE_FREED is

   overwritten with a pointer the caller has to free if the function

   returns successfully.  On failure, return NULL.  */

const char *

__nss_rewrite_field (const char *value, char **to_be_freed)

{

  *to_be_freed = NULL;

  if (value == NULL)

    return "";

  /* Search for non-allowed characters.  */

  const char *p = strpbrk (value, __nss_invalid_field_characters);

  if (p == NULL)

    return value;

  *to_be_freed = __strdup (value);

  if (*to_be_freed == NULL)

    return NULL;

  /* Switch pointer to freshly-allocated buffer.  */

  char *bad = *to_be_freed + (p - value);

  do

    {

      *bad = ' ';

      bad = strpbrk (bad + 1, __nss_invalid_field_characters);

    }

  while (bad != NULL);

  return *to_be_freed;

}