/****************************************************************************
 * libs/libc/dirent/lib_alphasort.c
 *
 *   Copyright (C) 2019 Gregory Nutt. All rights reserved.
 *   Author: Michael Jung <mijung@gmx.net>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <string.h>
#include <dirent.h>

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: alphasort
 *
 * Description:
 *   The  alphasort() function can be used as the comparison function compar()
 *   for scandir().  It sorts directory entries using strcoll on the strings
 *   (*a)->d_name and (*b)->d_name.
 *
 * Input Parameters:
 *   a - The first direntry to compare
 *   b - The second direntry to compare
 *
 * Returned Value:
 *   An integer less than, equal to, or greater than zero if the first
 *   argument is considered to be respectively less than, equal to, or greater
 *   than the second.
 *
 ****************************************************************************/

int alphasort(FAR const struct dirent **a, FAR const struct dirent **b)
{
#ifdef CONFIG_LIBC_LOCALE
  return strcoll((*a)->d_name, (*b)->d_name);
#else
  return strcmp((*a)->d_name, (*b)->d_name);
#endif
}