xref: /btstack/src/btstack_linked_list.h (revision d58a1b5f11ada8ddf896c41fff5a35e7f140c37e)
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
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7  *
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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.
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15  *    from this software without specific prior written permission.
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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
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37 
38 /*
39  *  btstack_linked_list.h
40  */
41 
42 #ifndef BTSTACK_LINKED_LIST_H
43 #define BTSTACK_LINKED_LIST_H
44 
45 #include "btstack_bool.h"
46 
47 #if defined __cplusplus
48 extern "C" {
49 #endif
50 
51 /* API_START */
52 
53 typedef struct btstack_linked_item {
54     struct btstack_linked_item *next; // <-- next element in list, or NULL
55 } btstack_linked_item_t;
56 
57 typedef btstack_linked_item_t * btstack_linked_list_t;
58 
59 typedef struct {
60 	int advance_on_next;
61     btstack_linked_item_t * prev;	// points to the item before the current one
62     btstack_linked_item_t * curr;	// points to the current item (to detect item removal)
63 } btstack_linked_list_iterator_t;
64 
65 
66 /**
67  * @brief Test if list is empty.
68  * @param list
69  * @returns true if list is empty
70  */
71 bool btstack_linked_list_empty(btstack_linked_list_t * list);
72 
73 /**
74  * @brief Add item to list as first element.
75  * @param list
76  * @param item
77  * @returns true if item was added, false if item already in list
78  */
79 bool btstack_linked_list_add(btstack_linked_list_t * list, btstack_linked_item_t *item);
80 
81 /**
82  * @brief Add item to list as last element.
83  * @param list
84  * @param item
85  * @returns true if item was added, false if item already in list
86  */
87 bool btstack_linked_list_add_tail(btstack_linked_list_t * list, btstack_linked_item_t *item);
88 
89 /**
90  * @brief Pop (get + remove) first element.
91  * @param list
92  * @returns first element or NULL if list is empty
93  */
94 btstack_linked_item_t * btstack_linked_list_pop(btstack_linked_list_t * list);
95 
96 /**
97  * @brief Remove item from list
98  * @param list
99  * @param item
100  * @returns true if item was removed, false if it is no't in list
101  */
102 bool btstack_linked_list_remove(btstack_linked_list_t * list, btstack_linked_item_t *item);
103 
104 /**
105  * @brief Get first element.
106  * @param list
107  * @returns first element or NULL if list is empty
108  */
109 btstack_linked_item_t * btstack_linked_list_get_first_item(btstack_linked_list_t * list);
110 
111 /**
112  * @brief Get last element.
113  * @param list
114  * @returns first element or NULL if list is empty
115  */
116 btstack_linked_item_t * btstack_linked_list_get_last_item(btstack_linked_list_t * list);
117 
118 /**
119  * @brief Counts number of items in list
120  * @returns number of items in list
121  */
122 int btstack_linked_list_count(btstack_linked_list_t * list);
123 
124 
125 
126 /**
127  * @brief Initialize Linked List Iterator
128  * @note robust against removal of current element by btstack_linked_list_remove
129  * @param it iterator context
130  * @param list
131  */
132 void btstack_linked_list_iterator_init(btstack_linked_list_iterator_t * it, btstack_linked_list_t * list);
133 
134 /**
135  * @brief Has next element
136  * @param it iterator context
137  * @returns true if next element is available
138  */
139 bool btstack_linked_list_iterator_has_next(btstack_linked_list_iterator_t * it);
140 
141 /**
142  * @brief Get next list eleemnt
143  * @param it iterator context
144  * @returns list element
145  */
146 btstack_linked_item_t * btstack_linked_list_iterator_next(btstack_linked_list_iterator_t * it);
147 
148 /**
149  * @brief Remove current list element from list
150  * @param it iterator context
151  */
152 void btstack_linked_list_iterator_remove(btstack_linked_list_iterator_t * it);
153 
154 /* API_END */
155 
156 void test_linked_list(void);
157 
158 
159 #if defined __cplusplus
160 }
161 #endif
162 
163 #endif // BTSTACK_LINKED_LIST_H
164