X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=include%2Fwimlib%2Flist.h;h=d556a56c6a142ddfaf2a732db3e4a4cb2912913b;hp=d6bd55c11013b54dadb2d0e615882058ace32e64;hb=719a063c87e3abab99b0fb53ebc80223fbf33123;hpb=8e5d4209c12a7436488d9a3d1f8d59383c5c48f2

diff --git a/include/wimlib/list.h b/include/wimlib/list.h
index d6bd55c1..d556a56c 100644
--- a/include/wimlib/list.h
+++ b/include/wimlib/list.h
@@ -3,42 +3,27 @@
  * This file is based on include/linux/list.h in the Linux kernel source code.
  */
 
-#ifndef _LINUX_LIST_H
-#define _LINUX_LIST_H
+#ifndef _WIMLIB_LIST_H
+#define _WIMLIB_LIST_H
 
+#include <stdbool.h>
 #include <stddef.h>
 
-struct list_head {
-	struct list_head *next, *prev;
-};
-struct hlist_head {
-	struct hlist_node *first;
-};
+/* Simple doubly linked list implementation.  */
 
-struct hlist_node {
-	struct hlist_node *next, **pprev;
+struct list_head {
+	struct list_head *next;
+	struct list_head *prev;
 };
 
-/*
- * Simple doubly linked list implementation.
- *
- * Some of the internal functions ("__xxx") are useful when
- * manipulating whole lists 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.
- */
 
 #define LIST_HEAD_INIT(name) { &(name), &(name) }
 
-#ifdef LIST_HEAD /* BSD sys/queue.h defines this... */
-#  undef LIST_HEAD
-#endif
+#undef LIST_HEAD /* BSD sys/queue.h defines this... */
+#define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name)
 
-#define LIST_HEAD(name) \
-	struct list_head name = LIST_HEAD_INIT(name)
-
-static inline void INIT_LIST_HEAD(struct list_head *list)
+static inline void
+INIT_LIST_HEAD(struct list_head *list)
 {
 	list->next = list;
 	list->prev = list;
@@ -50,9 +35,8 @@ static inline void INIT_LIST_HEAD(struct list_head *list)
  * This is only for internal list manipulation where we know
  * the prev/next entries already!
  */
-static inline void __list_add(struct list_head *new,
-			      struct list_head *prev,
-			      struct list_head *next)
+static inline void
+__list_add(struct list_head *new, struct list_head *prev, struct list_head *next)
 {
 	next->prev = new;
 	new->next = next;
@@ -68,7 +52,8 @@ static inline void __list_add(struct list_head *new,
  * Insert a new entry after the specified head.
  * This is good for implementing stacks.
  */
-static inline void list_add(struct list_head *new, struct list_head *head)
+static inline void
+list_add(struct list_head *new, struct list_head *head)
 {
 	__list_add(new, head, head->next);
 }
@@ -81,22 +66,26 @@ static inline void list_add(struct list_head *new, struct list_head *head)
  * Insert a new entry before the specified head.
  * This is useful for implementing queues.
  */
-static inline void list_add_tail(struct list_head *new, struct list_head *head)
+static inline void
+list_add_tail(struct list_head *new, struct list_head *head)
 {
 	__list_add(new, head->prev, head);
 }
 
-/*
- * Delete a list entry by making the prev/next entries
- * point to each other.
+/**
+ * list_replace - replace old entry by new one
+ * @old : the element to be replaced
+ * @new : the new element to insert
  *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
+ * If @old was empty, it will be overwritten.
  */
-static inline void __list_del(struct list_head * prev, struct list_head * next)
+static inline void
+list_replace(struct list_head *old, struct list_head *new)
 {
-	next->prev = prev;
-	prev->next = next;
+	new->next = old->next;
+	new->next->prev = new;
+	new->prev = old->prev;
+	new->prev->next = new;
 }
 
 /**
@@ -105,42 +94,29 @@ static inline void __list_del(struct list_head * prev, struct list_head * next)
  * Note: list_empty() on entry does not return true after this, the entry is
  * in an undefined state.
  */
-static inline void list_del(struct list_head *entry)
+static inline void
+list_del(struct list_head *entry)
 {
-	__list_del(entry->prev, entry->next);
-}
+	struct list_head *prev = entry->prev;
+	struct list_head *next = entry->next;
 
-/**
- * list_del_init - deletes entry from list and reinitialize it.
- * @entry: the element to delete from the list.
- */
-static inline void list_del_init(struct list_head *entry)
-{
-	list_del(entry);
-	INIT_LIST_HEAD(entry);
+	prev->next = next;
+	next->prev = prev;
 }
 
 /**
  * list_empty - tests whether a list is empty
  * @head: the list to test.
  */
-static inline int list_empty(const struct list_head *head)
+static inline bool
+list_empty(const struct list_head *head)
 {
 	return head->next == head;
 }
 
-/**
- * list_is_singular - tests whether a list has just one entry.
- * @head: the list to test.
- */
-static inline int list_is_singular(const struct list_head *head)
-{
-	return !list_empty(head) && (head->next == head->prev);
-}
-
-static inline void __list_splice(const struct list_head *list,
-				 struct list_head *prev,
-				 struct list_head *next)
+static inline void
+__list_splice(const struct list_head *list,
+	      struct list_head *prev, struct list_head *next)
 {
 	struct list_head *first = list->next;
 	struct list_head *last = list->prev;
@@ -157,37 +133,20 @@ static inline void __list_splice(const struct list_head *list,
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  */
-static inline void list_splice(const struct list_head *list,
-				struct list_head *head)
+static inline void
+list_splice(const struct list_head *list, struct list_head *head)
 {
 	if (!list_empty(list))
 		__list_splice(list, head, head->next);
 }
 
-/* Move the entire list @old to the list @new, overwriting it. */
-static inline void list_transfer(struct list_head *old,
-				 struct list_head *new)
-{
-	struct list_head *prev, *next;
-
-	if (list_empty(old)) {
-		INIT_LIST_HEAD(new);
-	} else {
-		prev = old->prev;
-		next = old->next;
-		new->next = next;
-		new->prev = prev;
-		prev->next = new;
-		next->prev = new;
-	}
-}
-
 /**
  * list_move - delete from one list and add as another's head
  * @list: the entry to move
  * @head: the head that will precede our entry
  */
-static inline void list_move(struct list_head *list, struct list_head *head)
+static inline void
+list_move(struct list_head *list, struct list_head *head)
 {
 	list_del(list);
 	list_add(list, head);
@@ -198,8 +157,8 @@ static inline void list_move(struct list_head *list, struct list_head *head)
  * @list: the entry to move
  * @head: the head that will follow our entry
  */
-static inline void list_move_tail(struct list_head *list,
-				  struct list_head *head)
+static inline void
+list_move_tail(struct list_head *list, struct list_head *head)
 {
 	list_del(list);
 	list_add_tail(list, head);
@@ -210,8 +169,8 @@ static inline void list_move_tail(struct list_head *list,
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  */
-static inline void list_splice_tail(struct list_head *list,
-				struct list_head *head)
+static inline void
+list_splice_tail(struct list_head *list, struct list_head *head)
 {
 	if (!list_empty(list))
 		__list_splice(list, head->prev, head);
@@ -226,6 +185,45 @@ static inline void list_splice_tail(struct list_head *list,
 #define list_entry(ptr, type, member) \
 	container_of(ptr, type, member)
 
+/**
+ * list_first_entry - get the first element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ *
+ * Note, that list is expected to be not empty.
+ */
+#define list_first_entry(ptr, type, member) \
+	list_entry((ptr)->next, type, member)
+
+/**
+ * list_last_entry - get the last element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ *
+ * Note, that list is expected to be not empty.
+ */
+#define list_last_entry(ptr, type, member) \
+	list_entry((ptr)->prev, type, member)
+
+/**
+ * list_next_entry - get the next element in list
+ * @pos:	the type * to cursor
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_next_entry(pos, member) \
+	list_entry((pos)->member.next, typeof(*(pos)), member)
+
+/**
+ * list_prev_entry - get the prev element in list
+ * @pos:	the type * to cursor
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_prev_entry(pos, member) \
+	list_entry((pos)->member.prev, typeof(*(pos)), member)
+
+
 /**
  * list_for_each	-	iterate over a list
  * @pos:	the &struct list_head to use as a loop cursor.
@@ -235,25 +233,26 @@ static inline void list_splice_tail(struct list_head *list,
 	for (pos = (head)->next; pos != (head); pos = pos->next)
 
 /**
- * list_for_each_safe - iterate over a list safe against removal of list entry
- * @pos:	the &struct list_head to use as a loop cursor.
- * @n:		another &struct list_head to use as temporary storage
+ * list_for_each_entry	-	iterate over list of given type
+ * @pos:	the type * to use as a loop cursor.
  * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
  */
-#define list_for_each_safe(pos, n, head) \
-	for (pos = (head)->next, n = pos->next; pos != (head); \
-		pos = n, n = pos->next)
+#define list_for_each_entry(pos, head, member)				\
+	for (pos = list_first_entry(head, typeof(*pos), member);	\
+	     &pos->member != (head);					\
+	     pos = list_next_entry(pos, member))
 
 /**
- * list_for_each_entry	-	iterate over list of given type
+ * list_for_each_entry_reverse - iterate backwards over list of given type.
  * @pos:	the type * to use as a loop cursor.
  * @head:	the head for your list.
  * @member:	the name of the list_struct within the struct.
  */
-#define list_for_each_entry(pos, head, member)				\
-	for (pos = list_entry((head)->next, typeof(*pos), member);	\
-	     &pos->member != (head); 	\
-	     pos = list_entry(pos->member.next, typeof(*pos), member))
+#define list_for_each_entry_reverse(pos, head, member)			\
+	for (pos = list_last_entry(head, typeof(*pos), member);		\
+	     &pos->member != (head); 					\
+	     pos = list_prev_entry(pos, member))
 
 /**
  * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
@@ -265,7 +264,7 @@ static inline void list_splice_tail(struct list_head *list,
 #define list_for_each_entry_safe(pos, n, head, member)			\
 	for (pos = list_entry((head)->next, typeof(*pos), member),	\
 		n = list_entry(pos->member.next, typeof(*pos), member);	\
-	     &pos->member != (head); 					\
+	     &pos->member != (head);					\
 	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
 
 /*
@@ -275,26 +274,35 @@ static inline void list_splice_tail(struct list_head *list,
  * You lose the ability to access the tail in O(1).
  */
 
-#define HLIST_HEAD_INIT { .first = NULL }
-#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }
-#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
-static inline void INIT_HLIST_NODE(struct hlist_node *h)
+struct hlist_head {
+	struct hlist_node *first;
+};
+
+struct hlist_node {
+	struct hlist_node *next;
+	struct hlist_node **pprev;
+};
+
+static inline void
+INIT_HLIST_HEAD(struct hlist_head *h)
 {
-	h->next = NULL;
-	h->pprev = NULL;
+	h->first = NULL;
 }
 
-static inline int hlist_unhashed(const struct hlist_node *h)
+static inline bool
+hlist_unhashed(const struct hlist_node *h)
 {
 	return !h->pprev;
 }
 
-static inline int hlist_empty(const struct hlist_head *h)
+static inline bool
+hlist_empty(const struct hlist_head *h)
 {
 	return !h->first;
 }
 
-static inline void __hlist_del(struct hlist_node *n)
+static inline void
+hlist_del(struct hlist_node *n)
 {
 	struct hlist_node *next = n->next;
 	struct hlist_node **pprev = n->pprev;
@@ -303,24 +311,8 @@ static inline void __hlist_del(struct hlist_node *n)
 		next->pprev = pprev;
 }
 
-static inline void hlist_del(struct hlist_node *n)
-{
-	__hlist_del(n);
-#if 0
-	n->next = LIST_POISON1;
-	n->pprev = LIST_POISON2;
-#endif
-}
-
-static inline void hlist_del_init(struct hlist_node *n)
-{
-	if (!hlist_unhashed(n)) {
-		__hlist_del(n);
-		INIT_HLIST_NODE(n);
-	}
-}
-
-static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
+static inline void
+hlist_add_head(struct hlist_node *n, struct hlist_head *h)
 {
 	struct hlist_node *first = h->first;
 	n->next = first;
@@ -332,38 +324,32 @@ static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
 
 #define hlist_entry(ptr, type, member) container_of(ptr,type,member)
 
-#define hlist_for_each(pos, head) \
-	for (pos = (head)->first; pos ; pos = pos->next)
-
-#define hlist_for_each_safe(pos, n, head) \
-	for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
-	     pos = n)
+#define hlist_entry_safe(ptr, type, member) \
+	({ typeof(ptr) ____ptr = (ptr); \
+	   ____ptr ? hlist_entry(____ptr, type, member) : NULL; \
+	})
 
 /**
  * hlist_for_each_entry	- iterate over list of given type
- * @tpos:	the type * to use as a loop cursor.
- * @pos:	the &struct hlist_node to use as a loop cursor.
+ * @pos:	the type * to use as a loop cursor.
  * @head:	the head for your list.
  * @member:	the name of the hlist_node within the struct.
  */
-#define hlist_for_each_entry(tpos, pos, head, member)			 \
-	for (pos = (head)->first;					 \
-	     pos &&							 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = pos->next)
+#define hlist_for_each_entry(pos, head, member)				\
+	for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\
+	     pos;							\
+	     pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
 
 /**
  * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
- * @tpos:	the type * to use as a loop cursor.
- * @pos:	the &struct hlist_node to use as a loop cursor.
+ * @pos:	the type * to use as a loop cursor.
  * @n:		another &struct hlist_node to use as temporary storage
  * @head:	the head for your list.
  * @member:	the name of the hlist_node within the struct.
  */
-#define hlist_for_each_entry_safe(tpos, pos, n, head, member) 		 \
-	for (pos = (head)->first;					 \
-	     pos && ({ n = pos->next; 1; }) && 				 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = n)
+#define hlist_for_each_entry_safe(pos, n, head, member) 		\
+	for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\
+	     pos && ({ n = pos->member.next; 1; });			\
+	     pos = hlist_entry_safe(n, typeof(*pos), member))
 
-#endif
+#endif /* _WIMLIB_LIST_H */