X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Flist.h;h=f0458b54e24d0d5235aa736428c12e9dfa6c0d60;hb=a2e0337875addaf08225fbf9b231435ba12a88b5;hp=47f275a019403c873d0d52341f7ab93fdb120d48;hpb=c2f1db8f83618e60dcded8303d14656d7d26b436;p=elogind.git

diff --git a/src/shared/list.h b/src/shared/list.h
index 47f275a01..f0458b54e 100644
--- a/src/shared/list.h
+++ b/src/shared/list.h
@@ -31,23 +31,23 @@
         t *name##_next, *name##_prev
 
 /* Initialize the list's head */
-#define LIST_HEAD_INIT(t,head)                                          \
+#define LIST_HEAD_INIT(head)                                            \
         do {                                                            \
                 (head) = NULL; }                                        \
         while(false)
 
 /* Initialize a list item */
-#define LIST_INIT(t,name,item)                                          \
+#define LIST_INIT(name,item)                                            \
         do {                                                            \
-                t *_item = (item);                                      \
+                typeof(*(item)) *_item = (item);                        \
                 assert(_item);                                          \
                 _item->name##_prev = _item->name##_next = NULL;         \
         } while(false)
 
 /* Prepend an item to the list */
-#define LIST_PREPEND(t,name,head,item)                                  \
+#define LIST_PREPEND(name,head,item)                                    \
         do {                                                            \
-                t **_head = &(head), *_item = (item);                   \
+                typeof(*(head)) **_head = &(head), *_item = (item);     \
                 assert(_item);                                          \
                 if ((_item->name##_next = *_head))                      \
                         _item->name##_next->name##_prev = _item;        \
@@ -55,10 +55,18 @@
                 *_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(t,name,head,item)                                   \
+#define LIST_REMOVE(name,head,item)                                     \
         do {                                                            \
-                t **_head = &(head), *_item = (item);                   \
+                typeof(*(head)) **_head = &(head), *_item = (item);     \
                 assert(_item);                                          \
                 if (_item->name##_next)                                 \
                         _item->name##_next->name##_prev = _item->name##_prev; \
@@ -72,29 +80,35 @@
         } while(false)
 
 /* Find the head of the list */
-#define LIST_FIND_HEAD(t,name,item,head)                                \
+#define LIST_FIND_HEAD(name,item,head)                                  \
         do {                                                            \
-                t *_item = (item);                                      \
-                assert(_item);                                          \
-                while (_item->name##_prev)                              \
-                       _item = _item->name##_prev;                      \
-                (head) = _item;                                         \
+                typeof(*(item)) *_item = (item);                        \
+                if (!_item)                                             \
+                        (head) = NULL;                                  \
+                else {                                                  \
+                        while (_item->name##_prev)                      \
+                                _item = _item->name##_prev;             \
+                        (head) = _item;                                 \
+                }                                                       \
         } while (false)
 
-/* Find the head of the list */
-#define LIST_FIND_TAIL(t,name,item,tail)                                \
+/* Find the tail of the list */
+#define LIST_FIND_TAIL(name,item,tail)                                  \
         do {                                                            \
-                t *_item = (item);                                      \
-                assert(_item);                                          \
-                while (_item->name##_next)                              \
-                        _item = _item->name##_next;                     \
-                (tail) = _item;                                         \
+                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(t,name,head,a,b)                              \
+#define LIST_INSERT_AFTER(name,head,a,b)                                \
         do {                                                            \
-                t **_head = &(head), *_a = (a), *_b = (b);              \
+                typeof(*(head)) **_head = &(head), *_a = (a), *_b = (b); \
                 assert(_b);                                             \
                 if (!_a) {                                              \
                         if ((_b->name##_next = *_head))                 \
@@ -123,3 +137,10 @@
 
 #define LIST_FOREACH_AFTER(name,i,p)                                    \
         for ((i) = (p)->name##_next; (i); (i) = (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))