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-rw-r--r--libosmocore/include/osmocore/linuxlist.h360
1 files changed, 360 insertions, 0 deletions
diff --git a/libosmocore/include/osmocore/linuxlist.h b/libosmocore/include/osmocore/linuxlist.h
new file mode 100644
index 000000000..fb99c5ec8
--- /dev/null
+++ b/libosmocore/include/osmocore/linuxlist.h
@@ -0,0 +1,360 @@
+#ifndef _LINUX_LLIST_H
+#define _LINUX_LLIST_H
+
+#include <stddef.h>
+
+#ifndef inline
+#define inline __inline__
+#endif
+
+static inline void prefetch(const void *x) {;}
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ *
+ * @ptr: the pointer to the member.
+ * @type: the type of the container struct this is embedded in.
+ * @member: the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (typeof( ((type *)0)->member ) *)(ptr); \
+ (type *)( (char *)__mptr - offsetof(type, member) );})
+
+
+/*
+ * These are non-NULL pointers that will result in page faults
+ * under normal circumstances, used to verify that nobody uses
+ * non-initialized llist entries.
+ */
+#define LLIST_POISON1 ((void *) 0x00100100)
+#define LLIST_POISON2 ((void *) 0x00200200)
+
+/*
+ * Simple doubly linked llist implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole llists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+struct llist_head {
+ struct llist_head *next, *prev;
+};
+
+#define LLIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LLIST_HEAD(name) \
+ struct llist_head name = LLIST_HEAD_INIT(name)
+
+#define INIT_LLIST_HEAD(ptr) do { \
+ (ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal llist manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __llist_add(struct llist_head *_new,
+ struct llist_head *prev,
+ struct llist_head *next)
+{
+ next->prev = _new;
+ _new->next = next;
+ _new->prev = prev;
+ prev->next = _new;
+}
+
+/**
+ * llist_add - add a new entry
+ * @new: new entry to be added
+ * @head: llist head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void llist_add(struct llist_head *_new, struct llist_head *head)
+{
+ __llist_add(_new, head, head->next);
+}
+
+/**
+ * llist_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: llist head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static inline void llist_add_tail(struct llist_head *_new, struct llist_head *head)
+{
+ __llist_add(_new, head->prev, head);
+}
+
+/*
+ * Delete a llist entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal llist manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __llist_del(struct llist_head * prev, struct llist_head * next)
+{
+ next->prev = prev;
+ prev->next = next;
+}
+
+/**
+ * llist_del - deletes entry from llist.
+ * @entry: the element to delete from the llist.
+ * Note: llist_empty on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void llist_del(struct llist_head *entry)
+{
+ __llist_del(entry->prev, entry->next);
+ entry->next = (struct llist_head *)LLIST_POISON1;
+ entry->prev = (struct llist_head *)LLIST_POISON2;
+}
+
+/**
+ * llist_del_init - deletes entry from llist and reinitialize it.
+ * @entry: the element to delete from the llist.
+ */
+static inline void llist_del_init(struct llist_head *entry)
+{
+ __llist_del(entry->prev, entry->next);
+ INIT_LLIST_HEAD(entry);
+}
+
+/**
+ * llist_move - delete from one llist and add as another's head
+ * @llist: the entry to move
+ * @head: the head that will precede our entry
+ */
+static inline void llist_move(struct llist_head *llist, struct llist_head *head)
+{
+ __llist_del(llist->prev, llist->next);
+ llist_add(llist, head);
+}
+
+/**
+ * llist_move_tail - delete from one llist and add as another's tail
+ * @llist: the entry to move
+ * @head: the head that will follow our entry
+ */
+static inline void llist_move_tail(struct llist_head *llist,
+ struct llist_head *head)
+{
+ __llist_del(llist->prev, llist->next);
+ llist_add_tail(llist, head);
+}
+
+/**
+ * llist_empty - tests whether a llist is empty
+ * @head: the llist to test.
+ */
+static inline int llist_empty(const struct llist_head *head)
+{
+ return head->next == head;
+}
+
+static inline void __llist_splice(struct llist_head *llist,
+ struct llist_head *head)
+{
+ struct llist_head *first = llist->next;
+ struct llist_head *last = llist->prev;
+ struct llist_head *at = head->next;
+
+ first->prev = head;
+ head->next = first;
+
+ last->next = at;
+ at->prev = last;
+}
+
+/**
+ * llist_splice - join two llists
+ * @llist: the new llist to add.
+ * @head: the place to add it in the first llist.
+ */
+static inline void llist_splice(struct llist_head *llist, struct llist_head *head)
+{
+ if (!llist_empty(llist))
+ __llist_splice(llist, head);
+}
+
+/**
+ * llist_splice_init - join two llists and reinitialise the emptied llist.
+ * @llist: the new llist to add.
+ * @head: the place to add it in the first llist.
+ *
+ * The llist at @llist is reinitialised
+ */
+static inline void llist_splice_init(struct llist_head *llist,
+ struct llist_head *head)
+{
+ if (!llist_empty(llist)) {
+ __llist_splice(llist, head);
+ INIT_LLIST_HEAD(llist);
+ }
+}
+
+/**
+ * llist_entry - get the struct for this entry
+ * @ptr: the &struct llist_head pointer.
+ * @type: the type of the struct this is embedded in.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_entry(ptr, type, member) \
+ container_of(ptr, type, member)
+
+/**
+ * llist_for_each - iterate over a llist
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @head: the head for your llist.
+ */
+#define llist_for_each(pos, head) \
+ for (pos = (head)->next, prefetch(pos->next); pos != (head); \
+ pos = pos->next, prefetch(pos->next))
+
+/**
+ * __llist_for_each - iterate over a llist
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @head: the head for your llist.
+ *
+ * This variant differs from llist_for_each() in that it's the
+ * simplest possible llist iteration code, no prefetching is done.
+ * Use this for code that knows the llist to be very short (empty
+ * or 1 entry) most of the time.
+ */
+#define __llist_for_each(pos, head) \
+ for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * llist_for_each_prev - iterate over a llist backwards
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @head: the head for your llist.
+ */
+#define llist_for_each_prev(pos, head) \
+ for (pos = (head)->prev, prefetch(pos->prev); pos != (head); \
+ pos = pos->prev, prefetch(pos->prev))
+
+/**
+ * llist_for_each_safe - iterate over a llist safe against removal of llist entry
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @n: another &struct llist_head to use as temporary storage
+ * @head: the head for your llist.
+ */
+#define llist_for_each_safe(pos, n, head) \
+ for (pos = (head)->next, n = pos->next; pos != (head); \
+ pos = n, n = pos->next)
+
+/**
+ * llist_for_each_entry - iterate over llist of given type
+ * @pos: the type * to use as a loop counter.
+ * @head: the head for your llist.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_for_each_entry(pos, head, member) \
+ for (pos = llist_entry((head)->next, typeof(*pos), member), \
+ prefetch(pos->member.next); \
+ &pos->member != (head); \
+ pos = llist_entry(pos->member.next, typeof(*pos), member), \
+ prefetch(pos->member.next))
+
+/**
+ * llist_for_each_entry_reverse - iterate backwards over llist of given type.
+ * @pos: the type * to use as a loop counter.
+ * @head: the head for your llist.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_for_each_entry_reverse(pos, head, member) \
+ for (pos = llist_entry((head)->prev, typeof(*pos), member), \
+ prefetch(pos->member.prev); \
+ &pos->member != (head); \
+ pos = llist_entry(pos->member.prev, typeof(*pos), member), \
+ prefetch(pos->member.prev))
+
+/**
+ * llist_for_each_entry_continue - iterate over llist of given type
+ * continuing after existing point
+ * @pos: the type * to use as a loop counter.
+ * @head: the head for your llist.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_for_each_entry_continue(pos, head, member) \
+ for (pos = llist_entry(pos->member.next, typeof(*pos), member), \
+ prefetch(pos->member.next); \
+ &pos->member != (head); \
+ pos = llist_entry(pos->member.next, typeof(*pos), member), \
+ prefetch(pos->member.next))
+
+/**
+ * llist_for_each_entry_safe - iterate over llist of given type safe against removal of llist entry
+ * @pos: the type * to use as a loop counter.
+ * @n: another type * to use as temporary storage
+ * @head: the head for your llist.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_for_each_entry_safe(pos, n, head, member) \
+ for (pos = llist_entry((head)->next, typeof(*pos), member), \
+ n = llist_entry(pos->member.next, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = n, n = llist_entry(n->member.next, typeof(*n), member))
+
+/**
+ * llist_for_each_rcu - iterate over an rcu-protected llist
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @head: the head for your llist.
+ */
+#define llist_for_each_rcu(pos, head) \
+ for (pos = (head)->next, prefetch(pos->next); pos != (head); \
+ pos = pos->next, ({ smp_read_barrier_depends(); 0;}), prefetch(pos->next))
+
+#define __llist_for_each_rcu(pos, head) \
+ for (pos = (head)->next; pos != (head); \
+ pos = pos->next, ({ smp_read_barrier_depends(); 0;}))
+
+/**
+ * llist_for_each_safe_rcu - iterate over an rcu-protected llist safe
+ * against removal of llist entry
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @n: another &struct llist_head to use as temporary storage
+ * @head: the head for your llist.
+ */
+#define llist_for_each_safe_rcu(pos, n, head) \
+ for (pos = (head)->next, n = pos->next; pos != (head); \
+ pos = n, ({ smp_read_barrier_depends(); 0;}), n = pos->next)
+
+/**
+ * llist_for_each_entry_rcu - iterate over rcu llist of given type
+ * @pos: the type * to use as a loop counter.
+ * @head: the head for your llist.
+ * @member: the name of the llist_struct within the struct.
+ */
+#define llist_for_each_entry_rcu(pos, head, member) \
+ for (pos = llist_entry((head)->next, typeof(*pos), member), \
+ prefetch(pos->member.next); \
+ &pos->member != (head); \
+ pos = llist_entry(pos->member.next, typeof(*pos), member), \
+ ({ smp_read_barrier_depends(); 0;}), \
+ prefetch(pos->member.next))
+
+
+/**
+ * llist_for_each_continue_rcu - iterate over an rcu-protected llist
+ * continuing after existing point.
+ * @pos: the &struct llist_head to use as a loop counter.
+ * @head: the head for your llist.
+ */
+#define llist_for_each_continue_rcu(pos, head) \
+ for ((pos) = (pos)->next, prefetch((pos)->next); (pos) != (head); \
+ (pos) = (pos)->next, ({ smp_read_barrier_depends(); 0;}), prefetch((pos)->next))
+
+
+#endif