Again single linked lists...
--- /dev/null Wed Dec 31 17:00:00 1969
+++ slist-2.5/include/linux/slist.h Wed Sep 25 16:47:26 2002
@@ -0,0 +1,109 @@
+#ifdef __KERNEL__
+#ifndef _LINUX_SLIST_H
+#define _LINUX_SLIST_H
+
+#include <asm/processor.h>
+
+/*
+ * Type-safe single linked list helper-functions.
+ * (originally taken from list.h)
+ *
+ * Thomas 'Dent' Mirlacher, Daniel Phillips,
+ * Andreas Borgk, Thunder from the hill
+ */
+
+#define INIT_SLIST_HEAD(name) \
+ (name->next = name)
+
+#define SLIST_HEAD(type,name) \
+ typeof(type) name = INIT_SLIST_HEAD(name)
+
+/**
+ * slist_add_front - add a new entry at the first slot, moving the old head
+ * to the second slot
+ * @new: new entry to be added
+ * @head: head of the single linked list
+ *
+ * Insert a new entry before the specified head.
+ * This is good for implementing stacks.
+ */
+
+#define slist_add_front(_new, _head) \
+do { \
+ (_new)->next = (_head); \
+ (_head) = (_new); \
+} while (0)
+
+
+
+/**
+ * slist_add - add a new entry
+ * @new: new entry to be added
+ * @head: head of the single linked list
+ *
+ * Insert a new entry before the specified head.
+ * This is good for implementing stacks.
+ *
+ * Careful: if you do this concurrently, _head
+ * might get into nirvana...
+ */
+#define slist_add(_new, _head) \
+do { \
+ (_new)->next = (_head)->next; \
+ (_head)->next = (_new); \
+ (_new) = (_head); \
+} while (0)
+
+/**
+ * slist_del - remove an entry from list
+ * @head: head to remove it from
+ * @entry: entry to be removed
+ */
+#define slist_del(_head, _entry) \
+do { \
+ (_head)->next = (_entry)->next; \
+ (_entry)->next = NULL; \
+} while (0)
+
+/**
+ * slist_del_single - untag a list from an entry
+ * @list: list entry to be untagged
+ */
+#define slist_del_single(_list) \
+ ((_list)->next = NULL)
+
+/**
+ * slist_pop - pop out list entry
+ * @list: entry to be popped out
+ *
+ * Pop out an entry from a list.
+ */
+#define slist_pop(_list) ({ \
+ typeof(_list) _NODE_ = _list; \
+ if (_list) { \
+ (_list) = (_list)->next; \
+ _NODE_->next = NULL; \
+ } \
+ _NODE_; })
+
+/**
+ * slist_for_each - iterate over a list
+ * @pos: the pointer to use as a loop counter.
+ * @head: the head for your list (this is also the first entry).
+ */
+#define slist_for_each(pos, head) \
+ for (pos = head; pos && ({ prefetch(pos->next); 1; }); \
+ pos = pos->next)
+
+/**
+ * slist_for_each_del - iterate over a list, popping off entries
+ * @pos: the pointer to use as a loop counter.
+ * @head: the head for your list (this is also the first entry).
+ */
+#define slist_for_each_del(pos, head) \
+ for (pos = slist_pop(head); pos && \
+ ({ prefetch(pos->next); 1; }); \
+ pos = slist_pop(head))
+
+#endif /* _LINUX_SLIST_H */
+#endif /* __KERNEL__ */
--
Lightweight Patch Manager, without pine.
If you have any objections (apart from who I am), tell me
Hi,
On Wed, 25 Sep 2002, Lightweight Patch Manager wrote:
> + * Andreas Borgk, Thunder from the hill
That poor guy's name is Andreas Bogk, for chrissake...
Thunder
--
assert(typeof((fool)->next) == typeof(fool)); /* wrong */
On Wed, 25 Sep 2002, Lightweight Patch Manager wrote:
> Again single linked lists...
And again with errors ;)
> +#define INIT_SLIST_HEAD(name) \
> + (name->next = name)
> +
> +#define SLIST_HEAD(type,name) \
> + typeof(type) name = INIT_SLIST_HEAD(name)
Fun, so the list head points to itself ...
> +#define slist_for_each(pos, head) \
> + for (pos = head; pos && ({ prefetch(pos->next); 1; }); \
> + pos = pos->next)
... imagine what that would do in combination with this macro.
Rik
--
Bravely reimplemented by the knights who say "NIH".
http://www.surriel.com/ http://distro.conectiva.com/
Spamtraps of the month: [email protected] [email protected]
Hi,
On Wed, 25 Sep 2002, Rik van Riel wrote:
> > +#define INIT_SLIST_HEAD(name) \
> > + (name->next = name)
> > +
> > +#define SLIST_HEAD(type,name) \
> > + typeof(type) name = INIT_SLIST_HEAD(name)
>
> Fun, so the list head points to itself ...
>
> > +#define slist_for_each(pos, head) \
> > + for (pos = head; pos && ({ prefetch(pos->next); 1; }); \
> > + pos = pos->next)
>
> ... imagine what that would do in combination with this macro.
I'm aware of that possibility. What would you initialize it to, if not the
list itself? (And BTW, anyone have a solution for slist_add()?)
We could set it to NULL, but where would we end?
#define INIT_SLIST_HEAD(name) \
(name->next = NULL)
#define SLIST_HEAD_INIT(name) name
Thunder
--
assert(typeof((fool)->next) == typeof(fool)); /* wrong */
On Thu, 26 Sep 2002, Thunder from the hill wrote:
> I'm aware of that possibility. What would you initialize it to, if not
> the list itself? (And BTW, anyone have a solution for slist_add()?)
If I were you, I'd take a large piece of paper and make
a drawing of what the data structure looks like and what
the various macros/functions are supposed to do.
That should make things easier.
regards,
Rik
--
A: No.
Q: Should I include quotations after my reply?
http://www.surriel.com/ http://distro.conectiva.com/
Hi,
On Thu, 26 Sep 2002, Rik van Riel wrote:
> If I were you, I'd take a large piece of paper and make
> a drawing of what the data structure looks like and what
> the various macros/functions are supposed to do.
Well, I know what they _should_ do. But I don't know what I should
initialize an empty list entry to. That's not got much spam in it...
Thunder
--
assert(typeof((fool)->next) == typeof(fool)); /* wrong */
On Thu, 26 Sep 2002, Thunder from the hill wrote:
> Hi,
>
> On Thu, 26 Sep 2002, Rik van Riel wrote:
> > If I were you, I'd take a large piece of paper and make
> > a drawing of what the data structure looks like and what
> > the various macros/functions are supposed to do.
>
> Well, I know what they _should_ do. But I don't know what I should
> initialize an empty list entry to. That's not got much spam in it...
Try with NULL.
Nicolas
On Thu, 26 Sep 2002, Thunder from the hill wrote:
> On Thu, 26 Sep 2002, Rik van Riel wrote:
> > If I were you, I'd take a large piece of paper and make
> > a drawing of what the data structure looks like and what
> > the various macros/functions are supposed to do.
>
> Well, I know what they _should_ do. But I don't know what I should
> initialize an empty list entry to.
And now you contradict yourself ;)
Please make a detailed picture of the data structure on
a piece of paper so you can check the code against the
picture and see if it really is doing the right thing.
Rik
--
A: No.
Q: Should I include quotations after my reply?
http://www.surriel.com/ http://distro.conectiva.com/