rtems/rfs/rtems-rfs-dir-hash.h

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @brief Provides a 32bit Hash of a String used to Search a Directory
0007  *
0008  * @ingroup rtems_rfs
0009  *
0010  * RTEMS File Systems Directory Hash provides a 32bit hash of a string. This is
0011  * used to search a directory.
0012  */
0013
0014 /*
0015  *  COPYRIGHT (c) 2010 Chris Johns <chrisj@rtems.org>
0016  *
0017  * Redistribution and use in source and binary forms, with or without
0018  * modification, are permitted provided that the following conditions
0019  * are met:
0020  * 1. Redistributions of source code must retain the above copyright
0021  *    notice, this list of conditions and the following disclaimer.
0022  * 2. Redistributions in binary form must reproduce the above copyright
0023  *    notice, this list of conditions and the following disclaimer in the
0024  *    documentation and/or other materials provided with the distribution.
0025  *
0026  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0027  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0028  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0029  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0030  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0031  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0032  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0033  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0034  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0035  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0036  * POSSIBILITY OF SUCH DAMAGE.
0037  */
0038
0039 #if !defined (_RTEMS_RFS_DIR_HASH_H_)
0040 #define _RTEMS_RFS_DIR_HASH_H_
0041
0042 #include <stddef.h>
0043 #include <stdint.h>
0044
0045 /**
0046  * Compute a hash of the key over the length of string.
0047  *
0048  * @param[in] key is a pointer to the key to calculate the hash of.
0049  * @param[in] length is the length of the key in bytes.
0050  *
0051  * @retval hash The computed uint32_t hash.
0052  */
0053 uint32_t rtems_rfs_dir_hash (const void *key, size_t length);
0054
0055 #endif