esp-idf/components/bt/porting/include/os/queue.h

213 lines
8.4 KiB
C

/*
* SPDX-FileCopyrightText: 2015-2022 The Apache Software Foundation (ASF)
*
* SPDX-License-Identifier: Apache-2.0
*
* SPDX-FileContributor: 2019-2022 Espressif Systems (Shanghai) CO LTD
*/
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
#ifndef _QUEUE_H_
#define _QUEUE_H_
/* The common BSD linked list queue macros are already defined here for ESP-IDF */
#include <sys/queue.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* This file defines circular queues. The other types of data structures:
* singly-linked lists, singly-linked tail queues, lists and tail queues
* are used from sys/queue.h
*
* A singly-linked list is headed by a single forward pointer. The elements
* are singly linked for minimum space and pointer manipulation overhead at
* the expense of O(n) removal for arbitrary elements. New elements can be
* added to the list after an existing element or at the head of the list.
* Elements being removed from the head of the list should use the explicit
* macro for this purpose for optimum efficiency. A singly-linked list may
* only be traversed in the forward direction. Singly-linked lists are ideal
* for applications with large datasets and few or no removals or for
* implementing a LIFO queue.
*
* A singly-linked tail queue is headed by a pair of pointers, one to the
* head of the list and the other to the tail of the list. The elements are
* singly linked for minimum space and pointer manipulation overhead at the
* expense of O(n) removal for arbitrary elements. New elements can be added
* to the list after an existing element, at the head of the list, or at the
* end of the list. Elements being removed from the head of the tail queue
* should use the explicit macro for this purpose for optimum efficiency.
* A singly-linked tail queue may only be traversed in the forward direction.
* Singly-linked tail queues are ideal for applications with large datasets
* and few or no removals or for implementing a FIFO queue.
*
* A list is headed by a single forward pointer (or an array of forward
* pointers for a hash table header). The elements are doubly linked
* so that an arbitrary element can be removed without a need to
* traverse the list. New elements can be added to the list before
* or after an existing element or at the head of the list. A list
* may only be traversed in the forward direction.
*
* A tail queue is headed by a pair of pointers, one to the head of the
* list and the other to the tail of the list. The elements are doubly
* linked so that an arbitrary element can be removed without a need to
* traverse the list. New elements can be added to the list before or
* after an existing element, at the head of the list, or at the end of
* the list. A tail queue may be traversed in either direction.
*
* A circle queue is headed by a pair of pointers, one to the head of the
* list and the other to the tail of the list. The elements are doubly
* linked so that an arbitrary element can be removed without a need to
* traverse the list. New elements can be added to the list before or after
* an existing element, at the head of the list, or at the end of the list.
* A circle queue may be traversed in either direction, but has a more
* complex end of list detection.
*
* For details on the use of these macros, see the queue(3) manual page.
*
*
* SLIST LIST STAILQ TAILQ CIRCLEQ
* _HEAD + + + + +
* _HEAD_INITIALIZER + + + + +
* _ENTRY + + + + +
* _INIT + + + + +
* _EMPTY + + + + +
* _FIRST + + + + +
* _NEXT + + + + +
* _PREV - - - + +
* _LAST - - + + +
* _FOREACH + + + + +
* _FOREACH_REVERSE - - - + +
* _INSERT_HEAD + + + + +
* _INSERT_BEFORE - + - + +
* _INSERT_AFTER + + + + +
* _INSERT_TAIL - - + + +
* _REMOVE_HEAD + - + - -
* _REMOVE + + + + +
*
*/
/*
* Circular queue declarations.
*/
#define CIRCLEQ_HEAD(name, type) \
struct name { \
struct type *cqh_first; /* first element */ \
struct type *cqh_last; /* last element */ \
}
#define CIRCLEQ_HEAD_INITIALIZER(head) \
{ (void *)&(head), (void *)&(head) }
#define CIRCLEQ_ENTRY(type) \
struct { \
struct type *cqe_next; /* next element */ \
struct type *cqe_prev; /* previous element */ \
}
/*
* Circular queue functions.
*/
#define CIRCLEQ_EMPTY(head) ((head)->cqh_first == (void *)(head))
#define CIRCLEQ_FIRST(head) ((head)->cqh_first)
#define CIRCLEQ_FOREACH(var, head, field) \
for ((var) = CIRCLEQ_FIRST((head)); \
(var) != (void *)(head) || ((var) = NULL); \
(var) = CIRCLEQ_NEXT((var), field))
#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
for ((var) = CIRCLEQ_LAST((head)); \
(var) != (void *)(head) || ((var) = NULL); \
(var) = CIRCLEQ_PREV((var), field))
#define CIRCLEQ_INIT(head) do { \
CIRCLEQ_FIRST((head)) = (void *)(head); \
CIRCLEQ_LAST((head)) = (void *)(head); \
} while (0)
#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
CIRCLEQ_NEXT((elm), field) = CIRCLEQ_NEXT((listelm), field); \
CIRCLEQ_PREV((elm), field) = (listelm); \
if (CIRCLEQ_NEXT((listelm), field) == (void *)(head)) \
CIRCLEQ_LAST((head)) = (elm); \
else \
CIRCLEQ_PREV(CIRCLEQ_NEXT((listelm), field), field) = (elm);\
CIRCLEQ_NEXT((listelm), field) = (elm); \
} while (0)
#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
CIRCLEQ_NEXT((elm), field) = (listelm); \
CIRCLEQ_PREV((elm), field) = CIRCLEQ_PREV((listelm), field); \
if (CIRCLEQ_PREV((listelm), field) == (void *)(head)) \
CIRCLEQ_FIRST((head)) = (elm); \
else \
CIRCLEQ_NEXT(CIRCLEQ_PREV((listelm), field), field) = (elm);\
CIRCLEQ_PREV((listelm), field) = (elm); \
} while (0)
#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
CIRCLEQ_NEXT((elm), field) = CIRCLEQ_FIRST((head)); \
CIRCLEQ_PREV((elm), field) = (void *)(head); \
if (CIRCLEQ_LAST((head)) == (void *)(head)) \
CIRCLEQ_LAST((head)) = (elm); \
else \
CIRCLEQ_PREV(CIRCLEQ_FIRST((head)), field) = (elm); \
CIRCLEQ_FIRST((head)) = (elm); \
} while (0)
#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
CIRCLEQ_NEXT((elm), field) = (void *)(head); \
CIRCLEQ_PREV((elm), field) = CIRCLEQ_LAST((head)); \
if (CIRCLEQ_FIRST((head)) == (void *)(head)) \
CIRCLEQ_FIRST((head)) = (elm); \
else \
CIRCLEQ_NEXT(CIRCLEQ_LAST((head)), field) = (elm); \
CIRCLEQ_LAST((head)) = (elm); \
} while (0)
#define CIRCLEQ_LAST(head) ((head)->cqh_last)
#define CIRCLEQ_NEXT(elm,field) ((elm)->field.cqe_next)
#define CIRCLEQ_PREV(elm,field) ((elm)->field.cqe_prev)
#define CIRCLEQ_REMOVE(head, elm, field) do { \
if (CIRCLEQ_NEXT((elm), field) == (void *)(head)) \
CIRCLEQ_LAST((head)) = CIRCLEQ_PREV((elm), field); \
else \
CIRCLEQ_PREV(CIRCLEQ_NEXT((elm), field), field) = \
CIRCLEQ_PREV((elm), field); \
if (CIRCLEQ_PREV((elm), field) == (void *)(head)) \
CIRCLEQ_FIRST((head)) = CIRCLEQ_NEXT((elm), field); \
else \
CIRCLEQ_NEXT(CIRCLEQ_PREV((elm), field), field) = \
CIRCLEQ_NEXT((elm), field); \
} while (0)
#ifdef __cplusplus
}
#endif
#endif /* !_SYS_QUEUE_H_ */