initial commit

1 files changed, 90 insertions, 0 deletions

diff --git a/list.h b/list.h
new file mode 100644
index 0000000000..c255e087e8
--- /dev/null
+++ b/list.h
@@ -0,0 +1,90 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+#ifndef foolisthfoo
+#define foolisthfoo
+
+/* 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)                                                  \
+    t *next, *prev
+
+/* Initialize the list's head */
+#define LIST_HEAD_INIT(t,item)                                          \
+        do {                                                            \
+                (item) = (t*) NULL; }                                   \
+        while(false)
+
+/* Initialize a list item */
+#define LIST_INIT(t,item)                                               \
+        do {                                                            \
+                t *_item = (item);                                      \
+                assert(_item);                                          \
+                _item->prev = _item->next = NULL;                       \
+        } while(false)
+
+/* Prepend an item to the list */
+#define LIST_PREPEND(t,head,item)                                       \
+        do {                                                            \
+                t **_head = &(head), *_item = (item);                   \
+                assert(_item);                                          \
+                if ((_item->next = *_head))                             \
+                        _item->next->prev = _item;                      \
+                _item->prev = NULL;                                     \
+                *_head = _item;                                         \
+        } while(false)
+
+/* Remove an item from the list */
+#define LIST_REMOVE(t,head,item)                                        \
+        do {                                                            \
+                t **_head = &(head), *_item = (item);                   \
+                assert(_item);                                          \
+                if (_item->next)                                        \
+                        _item->next->prev = _item->prev;                \
+                if (_item->prev)                                        \
+                        _item->prev->next = _item->next;                \
+                else {                                                  \
+                        assert(*_head == _item);                        \
+                        *_head = _item->next;                           \
+                }                                                       \
+                _item->next = _item->prev = NULL;                       \
+        } while(false)
+
+/* Find the head of the list */
+#define LIST_FIND_HEAD(t,item,head)                                     \
+        do {                                                            \
+                t **_head = (head), *_item = (item);                    \
+                *_head = _item;                                         \
+                assert(_head);                                          \
+                while ((*_head)->prev)                                  \
+                        *_head = (*_head)->prev;                        \
+        } while (false)
+
+/* Insert an item after another one (a = where, b = what) */
+#define LIST_INSERT_AFTER(t,head,a,b)                                   \
+        do {                                                            \
+                t **_head = &(head), *_a = (a), *_b = (b);              \
+                assert(_b);                                             \
+                if (!_a) {                                              \
+                        if ((_b->next = *_head))                        \
+                                _b->next->prev = _b;                    \
+                        _b->prev = NULL;                                \
+                        *_head = _b;                                    \
+                } else {                                                \
+                        if ((_b->next = _a->next))                      \
+                                _b->next->prev = _b;                    \
+                        _b->prev = _a;                                  \
+                        _a->next = _b;                                  \
+                }                                                       \
+        } while(false)
+
+#define LIST_FOREACH(i,head)                                            \
+        for (i = (head); i; i = i->next)
+
+#define LIST_FOREACH_SAFE(i,n,head)                                     \
+        for (i = (head); i && ((n = i->next), 1); i = n)
+
+#endif