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-rw-r--r--src/libbasic/include/basic/list.h182
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diff --git a/src/libbasic/include/basic/list.h b/src/libbasic/include/basic/list.h
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+++ b/src/libbasic/include/basic/list.h
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+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+/* The head of the linked list. Use this in the structure that shall
+ * contain the head of the linked list */
+#define LIST_HEAD(t,name) \
+ t *name
+
+/* The pointers in the linked list's items. Use this in the item structure */
+#define LIST_FIELDS(t,name) \
+ t *name##_next, *name##_prev
+
+/* Initialize the list's head */
+#define LIST_HEAD_INIT(head) \
+ do { \
+ (head) = NULL; } \
+ while (false)
+
+/* Initialize a list item */
+#define LIST_INIT(name,item) \
+ do { \
+ typeof(*(item)) *_item = (item); \
+ assert(_item); \
+ _item->name##_prev = _item->name##_next = NULL; \
+ } while (false)
+
+/* Prepend an item to the list */
+#define LIST_PREPEND(name,head,item) \
+ do { \
+ typeof(*(head)) **_head = &(head), *_item = (item); \
+ assert(_item); \
+ if ((_item->name##_next = *_head)) \
+ _item->name##_next->name##_prev = _item; \
+ _item->name##_prev = NULL; \
+ *_head = _item; \
+ } while (false)
+
+/* Append an item to the list */
+#define LIST_APPEND(name,head,item) \
+ do { \
+ typeof(*(head)) *_tail; \
+ LIST_FIND_TAIL(name,head,_tail); \
+ LIST_INSERT_AFTER(name,head,_tail,item); \
+ } while (false)
+
+/* Remove an item from the list */
+#define LIST_REMOVE(name,head,item) \
+ do { \
+ typeof(*(head)) **_head = &(head), *_item = (item); \
+ assert(_item); \
+ if (_item->name##_next) \
+ _item->name##_next->name##_prev = _item->name##_prev; \
+ if (_item->name##_prev) \
+ _item->name##_prev->name##_next = _item->name##_next; \
+ else { \
+ assert(*_head == _item); \
+ *_head = _item->name##_next; \
+ } \
+ _item->name##_next = _item->name##_prev = NULL; \
+ } while (false)
+
+/* Find the head of the list */
+#define LIST_FIND_HEAD(name,item,head) \
+ do { \
+ typeof(*(item)) *_item = (item); \
+ if (!_item) \
+ (head) = NULL; \
+ else { \
+ while (_item->name##_prev) \
+ _item = _item->name##_prev; \
+ (head) = _item; \
+ } \
+ } while (false)
+
+/* Find the tail of the list */
+#define LIST_FIND_TAIL(name,item,tail) \
+ do { \
+ typeof(*(item)) *_item = (item); \
+ if (!_item) \
+ (tail) = NULL; \
+ else { \
+ while (_item->name##_next) \
+ _item = _item->name##_next; \
+ (tail) = _item; \
+ } \
+ } while (false)
+
+/* Insert an item after another one (a = where, b = what) */
+#define LIST_INSERT_AFTER(name,head,a,b) \
+ do { \
+ typeof(*(head)) **_head = &(head), *_a = (a), *_b = (b); \
+ assert(_b); \
+ if (!_a) { \
+ if ((_b->name##_next = *_head)) \
+ _b->name##_next->name##_prev = _b; \
+ _b->name##_prev = NULL; \
+ *_head = _b; \
+ } else { \
+ if ((_b->name##_next = _a->name##_next)) \
+ _b->name##_next->name##_prev = _b; \
+ _b->name##_prev = _a; \
+ _a->name##_next = _b; \
+ } \
+ } while (false)
+
+/* Insert an item before another one (a = where, b = what) */
+#define LIST_INSERT_BEFORE(name,head,a,b) \
+ do { \
+ typeof(*(head)) **_head = &(head), *_a = (a), *_b = (b); \
+ assert(_b); \
+ if (!_a) { \
+ if (!*_head) { \
+ _b->name##_next = NULL; \
+ _b->name##_prev = NULL; \
+ *_head = _b; \
+ } else { \
+ typeof(*(head)) *_tail = (head); \
+ while (_tail->name##_next) \
+ _tail = _tail->name##_next; \
+ _b->name##_next = NULL; \
+ _b->name##_prev = _tail; \
+ _tail->name##_next = _b; \
+ } \
+ } else { \
+ if ((_b->name##_prev = _a->name##_prev)) \
+ _b->name##_prev->name##_next = _b; \
+ _b->name##_next = _a; \
+ _a->name##_prev = _b; \
+ } \
+ } while (false)
+
+#define LIST_JUST_US(name,item) \
+ (!(item)->name##_prev && !(item)->name##_next) \
+
+#define LIST_FOREACH(name,i,head) \
+ for ((i) = (head); (i); (i) = (i)->name##_next)
+
+#define LIST_FOREACH_SAFE(name,i,n,head) \
+ for ((i) = (head); (i) && (((n) = (i)->name##_next), 1); (i) = (n))
+
+#define LIST_FOREACH_BEFORE(name,i,p) \
+ for ((i) = (p)->name##_prev; (i); (i) = (i)->name##_prev)
+
+#define LIST_FOREACH_AFTER(name,i,p) \
+ for ((i) = (p)->name##_next; (i); (i) = (i)->name##_next)
+
+/* Iterate through all the members of the list p is included in, but skip over p */
+#define LIST_FOREACH_OTHERS(name,i,p) \
+ for (({ \
+ (i) = (p); \
+ while ((i) && (i)->name##_prev) \
+ (i) = (i)->name##_prev; \
+ if ((i) == (p)) \
+ (i) = (p)->name##_next; \
+ }); \
+ (i); \
+ (i) = (i)->name##_next == (p) ? (p)->name##_next : (i)->name##_next)
+
+/* Loop starting from p->next until p->prev.
+ p can be adjusted meanwhile. */
+#define LIST_LOOP_BUT_ONE(name,i,head,p) \
+ for ((i) = (p)->name##_next ? (p)->name##_next : (head); \
+ (i) != (p); \
+ (i) = (i)->name##_next ? (i)->name##_next : (head))