1 #ifndef __LIST_H 2 #define __LIST_H 3 4 /* This file is from Linux Kernel (include/linux/list.h) 5 * and modified by simply removing hardware prefetching of list items. 6 * Here by copyright, credits attributed to wherever they belong. 7 * Kulesh Shanmugasundaram (kulesh [squiggly] isis.poly.edu) 8 */ 9 10 /* 11 * Simple doubly linked list implementation. 12 * 13 * Some of the internal functions ("__xxx") are useful when 14 * manipulating whole lists rather than single entries, as 15 * sometimes we already know the next/prev entries and we can 16 * generate better code by using them directly rather than 17 * using the generic single-entry routines. 18 */ 19 20 struct list_head { 21 struct list_head *next, *prev; 22 }; 23 24 #define LIST_HEAD_INIT(name) { &(name), &(name) } 25 26 #define LIST_HEAD(name) \ 27 struct list_head name = LIST_HEAD_INIT(name) 28 29 #define INIT_LIST_HEAD(ptr) do { \ 30 (ptr)->next = (ptr); (ptr)->prev = (ptr); \ 31 } while (0) 32 33 /* 34 * Insert a new entry between two known consecutive entries. 35 * 36 * This is only for internal list manipulation where we know 37 * the prev/next entries already! 38 */ 39 static inline void __list_add(struct list_head *New, 40 struct list_head *prev, 41 struct list_head *next) 42 { 43 next->prev = New; 44 New->next = next; 45 New->prev = prev; 46 prev->next = New; 47 } 48 49 /** 50 * list_add - add a new entry 51 * @New: new entry to be added 52 * @head: list head to add it after 53 * 54 * Insert a new entry after the specified head. 55 * This is good for implementing stacks. 56 */ 57 static inline void list_add(struct list_head *New, struct list_head *head) 58 { 59 __list_add(New, head, head->next); 60 } 61 62 /** 63 * list_add_tail - add a new entry 64 * @New: new entry to be added 65 * @head: list head to add it before 66 * 67 * Insert a new entry before the specified head. 68 * This is useful for implementing queues. 69 */ 70 static inline void list_add_tail(struct list_head *New, struct list_head *head) 71 { 72 __list_add(New, head->prev, head); 73 } 74 75 /* 76 * Delete a list entry by making the prev/next entries 77 * point to each other. 78 * 79 * This is only for internal list manipulation where we know 80 * the prev/next entries already! 81 */ 82 static inline void __list_del(struct list_head *prev, struct list_head *next) 83 { 84 next->prev = prev; 85 prev->next = next; 86 } 87 88 /** 89 * list_del - deletes entry from list. 90 * @entry: the element to delete from the list. 91 * Note: list_empty on entry does not return true after this, the entry is in an undefined state. 92 */ 93 static inline void list_del(struct list_head *entry) 94 { 95 __list_del(entry->prev, entry->next); 96 entry->next = (struct list_head *) 0; 97 entry->prev = (struct list_head *) 0; 98 } 99 100 /** 101 * list_del_init - deletes entry from list and reinitialize it. 102 * @entry: the element to delete from the list. 103 */ 104 static inline void list_del_init(struct list_head *entry) 105 { 106 __list_del(entry->prev, entry->next); 107 INIT_LIST_HEAD(entry); 108 } 109 110 /** 111 * list_move - delete from one list and add as another's head 112 * @list: the entry to move 113 * @head: the head that will precede our entry 114 */ 115 static inline void list_move(struct list_head *list, struct list_head *head) 116 { 117 __list_del(list->prev, list->next); 118 list_add(list, head); 119 } 120 121 /** 122 * list_move_tail - delete from one list and add as another's tail 123 * @list: the entry to move 124 * @head: the head that will follow our entry 125 */ 126 static inline void list_move_tail(struct list_head *list, 127 struct list_head *head) 128 { 129 __list_del(list->prev, list->next); 130 list_add_tail(list, head); 131 } 132 133 /** 134 * list_empty - tests whether a list is empty 135 * @head: the list to test. 136 */ 137 static inline int list_empty(struct list_head *head) 138 { 139 return head->next == head; 140 } 141 142 static inline void __list_splice(struct list_head *list, 143 struct list_head *head) 144 { 145 struct list_head *first = list->next; 146 struct list_head *last = list->prev; 147 struct list_head *at = head->next; 148 149 first->prev = head; 150 head->next = first; 151 152 last->next = at; 153 at->prev = last; 154 } 155 156 /** 157 * list_splice - join two lists 158 * @list: the new list to add. 159 * @head: the place to add it in the first list. 160 */ 161 static inline void list_splice(struct list_head *list, struct list_head *head) 162 { 163 if (!list_empty(list)) 164 __list_splice(list, head); 165 } 166 167 /** 168 * list_splice_init - join two lists and reinitialise the emptied list. 169 * @list: the new list to add. 170 * @head: the place to add it in the first list. 171 * 172 * The list at @list is reinitialised 173 */ 174 static inline void list_splice_init(struct list_head *list, 175 struct list_head *head) 176 { 177 if (!list_empty(list)) { 178 __list_splice(list, head); 179 INIT_LIST_HEAD(list); 180 } 181 } 182 183 /** 184 * list_entry - get the struct for this entry 185 * @ptr: the &struct list_head pointer. 186 * @type: the type of the struct this is embedded in. 187 * @member: the name of the list_struct within the struct. 188 */ 189 #ifdef __REACTOS__ 190 #define list_entry(ptr, type, member) \ 191 ((type *)((char *)(ptr)-(size_t)(&((type *)0)->member))) 192 #else /* __REACTOS__ */ 193 #define list_entry(ptr, type, member) \ 194 ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member))) 195 #endif /* __REACTOS__ */ 196 197 /** 198 * list_for_each - iterate over a list 199 * @pos: the &struct list_head to use as a loop counter. 200 * @head: the head for your list. 201 */ 202 #define list_for_each(pos, head) \ 203 for (pos = (head)->next; pos != (head); \ 204 pos = pos->next) 205 /** 206 * list_for_each_prev - iterate over a list backwards 207 * @pos: the &struct list_head to use as a loop counter. 208 * @head: the head for your list. 209 */ 210 #define list_for_each_prev(pos, head) \ 211 for (pos = (head)->prev; pos != (head); \ 212 pos = pos->prev) 213 214 /** 215 * list_for_each_safe - iterate over a list safe against removal of list entry 216 * @pos: the &struct list_head to use as a loop counter. 217 * @n: another &struct list_head to use as temporary storage 218 * @head: the head for your list. 219 */ 220 #define list_for_each_safe(pos, n, head) \ 221 for (pos = (head)->next, n = pos->next; pos != (head); \ 222 pos = n, n = pos->next) 223 224 /** 225 * list_for_each_entry - iterate over list of given type 226 * @pos: the type * to use as a loop counter. 227 * @head: the head for your list. 228 * @member: the name of the list_struct within the struct. 229 */ 230 #define list_for_each_entry(pos, head, member) \ 231 for (pos = list_entry((head)->next, typeof(*pos), member); \ 232 &pos->member != (head); \ 233 pos = list_entry(pos->member.next, typeof(*pos), member)) 234 235 /** 236 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry 237 * @pos: the type * to use as a loop counter. 238 * @n: another type * to use as temporary storage 239 * @head: the head for your list. 240 * @member: the name of the list_struct within the struct. 241 */ 242 #define list_for_each_entry_safe(pos, n, head, member) \ 243 for (pos = list_entry((head)->next, typeof(*pos), member), \ 244 n = list_entry(pos->member.next, typeof(*pos), member); \ 245 &pos->member != (head); \ 246 pos = n, n = list_entry(n->member.next, typeof(*n), member)) 247 248 249 #endif 250