xref: /btstack/src/btstack_linked_list.h (revision bc37f7b0d0a3eaa5763a873c5730bc14b849aaa0)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
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35  *
36  */
37 
38 /*
39  *  btstack_linked_list.h
40  */
41 
42 #ifndef __BTSTACK_LINKED_LIST_H
43 #define __BTSTACK_LINKED_LIST_H
44 
45 #if defined __cplusplus
46 extern "C" {
47 #endif
48 
49 typedef struct btstack_linked_item {
50     struct btstack_linked_item *next; // <-- next element in list, or NULL
51 } btstack_linked_item_t;
52 
53 typedef btstack_linked_item_t * btstack_linked_list_t;
54 
55 typedef struct {
56 	int advance_on_next;
57     btstack_linked_item_t * prev;	// points to the item before the current one
58     btstack_linked_item_t * curr;	// points to the current item (to detect item removal)
59 } btstack_linked_list_iterator_t;
60 
61 
62 // test if list is empty
63 int                     btstack_linked_list_empty(btstack_linked_list_t * list);
64 // add item to list as first element
65 void                    btstack_linked_list_add(btstack_linked_list_t * list, btstack_linked_item_t *item);
66 // add item to list as last element
67 void                    btstack_linked_list_add_tail(btstack_linked_list_t * list, btstack_linked_item_t *item);
68 // remove item from list
69 int                     btstack_linked_list_remove(btstack_linked_list_t * list, btstack_linked_item_t *item);
70 // find the last item in the list
71 btstack_linked_item_t * btstack_linked_list_get_last_item(btstack_linked_list_t * list);
72 
73 /**
74  * @brief Counts number of items in list
75  * @returns number of items in list
76  */
77 int btstack_linked_list_count(btstack_linked_list_t * list);
78 
79 //
80 // iterator for linked lists. allows to remove current element.
81 // robust against removal of current element by btstack_linked_list_remove.
82 //
83 void            btstack_linked_list_iterator_init(btstack_linked_list_iterator_t * it, btstack_linked_list_t * list);
84 int             btstack_linked_list_iterator_has_next(btstack_linked_list_iterator_t * it);
85 btstack_linked_item_t * btstack_linked_list_iterator_next(btstack_linked_list_iterator_t * it);
86 void            btstack_linked_list_iterator_remove(btstack_linked_list_iterator_t * it);
87 
88 void test_linked_list(void);
89 
90 #if defined __cplusplus
91 }
92 #endif
93 
94 #endif // __BTSTACK_LINKED_LIST_H
95