wip

1 files changed, 182 insertions, 0 deletions

diff --git a/src/libsystemd-basic/include/systemd-basic/list.h b/src/libsystemd-basic/include/systemd-basic/list.h
new file mode 100644
index 0000000000..5962aa4211
--- /dev/null
+++ b/src/libsystemd-basic/include/systemd-basic/list.h
@@ -0,0 +1,182 @@
+#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))