X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=include%2Furcu%2Fhlist.h;h=9a1eb21e33990ea0bad4bb4e9388c6fbc1278208;hb=HEAD;hp=344481133eac2051f4d7ab85e6188f51887e7dd7;hpb=6893800a4d1cc14dff0395ddcd660a5138db183d;p=urcu.git

diff --git a/include/urcu/hlist.h b/include/urcu/hlist.h
index 3444811..9a1eb21 100644
--- a/include/urcu/hlist.h
+++ b/include/urcu/hlist.h
@@ -1,3 +1,8 @@
+// SPDX-FileCopyrightText: 2009 Novell Inc.
+// SPDX-FileCopyrightText: 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+//
+// SPDX-License-Identifier: LGPL-2.1-only
+
 #ifndef _KCOMPAT_HLIST_H
 #define _KCOMPAT_HLIST_H
 
@@ -5,18 +10,11 @@
  * Kernel sourcecode compatible lightweight single pointer list head useful
  * for implementing hash tables
  *
- * Copyright (C) 2009 Novell Inc.
- *
  * Author: Jan Blunck <jblunck@suse.de>
- *
- * Copyright (C) 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU Lesser General Public License version 2.1 as
- * published by the Free  Software Foundation.
  */
 
 #include <stddef.h>
+#include <urcu/compiler.h>
 
 struct cds_hlist_head {
 	struct cds_hlist_node *next;
@@ -40,8 +38,14 @@ void CDS_INIT_HLIST_HEAD(struct cds_hlist_head *ptr)
 	{ .next = NULL }
 
 /* Get typed element from list at a given position. */
-#define cds_hlist_entry(ptr, type, member) \
-	((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member)))
+#define cds_hlist_entry(ptr, type, member)	caa_container_of(ptr, type, member)
+
+/* Get typed element from list at a given position, keeping NULL pointers. */
+#define cds_hlist_entry_safe(ptr, type, member)					\
+	({									\
+		__typeof__(ptr) ____ret = (ptr);				\
+		____ret ? cds_hlist_entry(____ret, type, member) : NULL;	\
+	})
 
 /* Add new element at the head of the list. */
 static inline
@@ -65,12 +69,12 @@ void cds_hlist_del(struct cds_hlist_node *elem)
 }
 
 #define cds_hlist_for_each(pos, head) \
-	for (pos = (head)->next; pos != NULL; pos = pos->next)
+	for (pos = (head)->next; (pos) != NULL; pos = (pos)->next)
 
 #define cds_hlist_for_each_safe(pos, p, head) \
 	for (pos = (head)->next; \
-		(pos != NULL) && (p = pos->next, 1); \
-		pos = p)
+		((pos) != NULL) && (p = (pos)->next, 1); \
+		pos = (p))
 
 /*
  * cds_hlist_for_each_entry and cds_hlist_for_each_entry_safe take
@@ -80,31 +84,27 @@ void cds_hlist_del(struct cds_hlist_node *elem)
  */
 #define cds_hlist_for_each_entry(entry, pos, head, member) \
 	for (pos = (head)->next, \
-			entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
-		pos != NULL; \
-		pos = pos->next, \
-			entry = cds_hlist_entry(pos, __typeof__(*entry), member))
+			entry = cds_hlist_entry(pos, __typeof__(*(entry)), member); \
+		(pos) != NULL; \
+		pos = (pos)->next, \
+			entry = cds_hlist_entry(pos, __typeof__(*(entry)), member))
 
 #define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \
 	for (pos = (head)->next, \
-			entry = cds_hlist_entry(pos, __typeof__(*entry), member); \
-		(pos != NULL) && (p = pos->next, 1); \
-		pos = p, \
+			entry = cds_hlist_entry(pos, __typeof__(*(entry)), member); \
+		((pos) != NULL) && (p = (pos)->next, 1); \
+		pos = (p), \
 			entry = cds_hlist_entry(pos, __typeof__(*entry), member))
 
 #define cds_hlist_for_each_entry_2(entry, head, member) \
-	for (entry = ((head)->next == NULL ? NULL \
-			: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
-		entry != NULL; \
-		entry = (entry->member.next == NULL ? NULL \
-			: cds_hlist_entry(entry->member.next, __typeof__(*entry), member)))
+	for (entry = cds_hlist_entry_safe((head)->next, __typeof__(*(entry)), member); \
+		(entry) != NULL; \
+		entry = cds_hlist_entry_safe((entry)->member.next, __typeof__(*(entry)), member))
 
 #define cds_hlist_for_each_entry_safe_2(entry, e, head, member) \
-	for (entry = ((head)->next == NULL ? NULL \
-			: cds_hlist_entry((head)->next, __typeof__(*entry), member)); \
-		(entry != NULL) && (e = (entry->member.next == NULL ? NULL \
-					: cds_hlist_entry(entry->member.next, \
-						__typeof__(*entry), member)), 1); \
+	for (entry = cds_hlist_entry_safe((head)->next, __typeof__(*(entry)), member); \
+		((entry) != NULL) && (e = (cds_hlist_entry_safe((entry)->member.next, \
+						__typeof__(*(entry)), member)), 1); \
 		entry = e)
 
 #endif	/* _KCOMPAT_HLIST_H */