cpukit/libdrvmgr/drvmgr_list.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /* Driver Manager List Interface Implementation.
0004  *
0005  * COPYRIGHT (c) 2009 Cobham Gaisler AB.
0006  *
0007  * Redistribution and use in source and binary forms, with or without
0008  * modification, are permitted provided that the following conditions
0009  * are met:
0010  * 1. Redistributions of source code must retain the above copyright
0011  *    notice, this list of conditions and the following disclaimer.
0012  * 2. Redistributions in binary form must reproduce the above copyright
0013  *    notice, this list of conditions and the following disclaimer in the
0014  *    documentation and/or other materials provided with the distribution.
0015  *
0016  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0017  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0018  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0019  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0020  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0021  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0022  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0023  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0024  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0025  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0026  * POSSIBILITY OF SUCH DAMAGE.
0027  */
0028
0029 #include <stdlib.h>
0030 #include <drvmgr/drvmgr_list.h>
0031
0032 /* LIST interface */
0033
0034 void drvmgr_list_init(struct drvmgr_list *list, int offset)
0035 {
0036     list->head = list->tail = NULL;
0037     list->ofs = offset;
0038 }
0039
0040 void drvmgr_list_empty(struct drvmgr_list *list)
0041 {
0042     list->head = list->tail = NULL;
0043 }
0044
0045 void drvmgr_list_add_head(struct drvmgr_list *list, void *entry)
0046 {
0047     LIST_FIELD(list, entry) = list->head;
0048     if (list->head == NULL)
0049         list->tail = entry;
0050     list->head = entry;
0051 }
0052
0053 void drvmgr_list_add_tail(struct drvmgr_list *list, void *entry)
0054 {
0055     if (list->tail == NULL)
0056         list->head = entry;
0057     else
0058         LIST_FIELD(list, list->tail) = entry;
0059     LIST_FIELD(list, entry) = NULL;
0060     list->tail = entry;
0061 }
0062
0063 void drvmgr_list_remove_head(struct drvmgr_list *list)
0064 {
0065     list->head = LIST_FIELD(list, list->head);
0066     if (list->head == NULL)
0067         list->tail = NULL;
0068 }
0069
0070 void drvmgr_list_remove(struct drvmgr_list *list, void *entry)
0071 {
0072     void **prevptr = &list->head;
0073     void *curr, *prev;
0074
0075     prev = NULL;
0076     curr = list->head;
0077     while (curr != entry) {
0078         prev = curr;
0079         prevptr = &LIST_FIELD(list, curr);
0080         curr = LIST_FIELD(list, curr);
0081     }
0082     *prevptr = LIST_FIELD(list, entry);
0083     if (list->tail == entry)
0084         list->tail = prev;
0085 }