[PATCH][2.5] Single linked lists for Linux, overly complicated v2

Lightweight Patch Manager (patch@luckynet.dynu.com)
Thu, 26 Sep 2002 17:41:24 +0000


This time I've taken care of the various comments. It's not exactly
been cool, but I saw where my details conflicted. NULL is supposed to
be NULL.

One more for: slist_for_each_round()

slist_del*() is still overly complicated. Shall I resume the easy
version of it?

--- /dev/null Wed Dec 31 17:00:00 1969
+++ slist-2.5/include/linux/slist.h Thu Sep 26 11:34:55 2002
@@ -0,0 +1,154 @@
+#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 Bogk, Thunder from the hill
+ */
+
+#define INIT_SLIST_HEAD(name) \
+ (name->next = name)
+
+#define SLIST_HEAD_INIT(name) \
+ { .next = NULL; }
+
+#define SLIST_HEAD(type,name) \
+ typeof(type) name = SLIST_HEAD_INIT(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_in, _head_in) \
+do { \
+ typeof(_head_in) _head = _head_in, \
+ _new = _new_in; \
+ _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_in, _head_in) \
+do { \
+ typeof(_head_in) _head = (_head_in), \
+ _new = (_new_in); \
+ _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(_entry_in) \
+({ \
+ typeof(_entry_in) _entry = (_entry_in), _head = \
+ kmalloc(sizeof(_entry), GFP_KERNEL), _free; \
+ if (_head) { \
+ memcpy(_head, (_entry), sizeof(_entry)); \
+ _free = (_entry); \
+ (_entry) = (_entry)->next; \
+ kfree(_free); \
+ _head->next = NULL; \
+ _head; \
+ } else \
+ NULL; \
+})
+
+/**
+ * slist_del_init - remove an entry from list and initialize it
+ * @head: head to remove it from
+ * @entry: entry to be removed
+ */
+#define slist_del_init(_entry) \
+({ \
+ typeof(_entry_in) _entry = (_entry_in), _head = \
+ kmalloc(sizeof(_entry), GFP_KERNEL), _free; \
+ if (_head) { \
+ memcpy(_head, (_entry), sizeof(_entry)); \
+ _free = (_entry); \
+ (_entry) = (_entry)->next; \
+ kfree(_free); \
+ _head->next = _head; \
+ _head; \
+ } else \
+ NULL; \
+})
+
+/**
+ * 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_in) ({ \
+ typeof(_list_in) _list = (_list_in), \
+ _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_round - iterate over a round 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 && pos != head && \
+ ({ 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

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