X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=urcu%2Fstatic%2Furcu-pointer.h;h=28333c57746e927bfc44e06e0a9fcc2b0e4794e2;hb=613086f69b4c8e6cc1b73b4e93d6d0497825d1ee;hp=48dc5bf506d86b06ddb1b5b4cf72066508634493;hpb=bdffa73aa208ad5f1e5b3a3cb6cbf86ac6996559;p=urcu.git

diff --git a/urcu/static/urcu-pointer.h b/urcu/static/urcu-pointer.h
index 48dc5bf..28333c5 100644
--- a/urcu/static/urcu-pointer.h
+++ b/urcu/static/urcu-pointer.h
@@ -6,8 +6,8 @@
  *
  * Userspace RCU header. Operations on pointers.
  *
- * TO BE INCLUDED ONLY IN LGPL-COMPATIBLE CODE. See urcu-pointer.h for
- * linking dynamically with the userspace rcu library.
+ * TO BE INCLUDED ONLY IN CODE THAT IS TO BE RECOMPILED ON EACH LIBURCU
+ * RELEASE. See urcu.h for linking dynamically with the userspace rcu library.
  *
  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
@@ -36,7 +36,7 @@
 
 #ifdef __cplusplus
 extern "C" {
-#endif 
+#endif
 
 /**
  * _rcu_dereference - reads (copy) a RCU-protected pointer to a local variable
@@ -59,9 +59,14 @@ extern "C" {
  * addition to forthcoming C++ standard.
  *
  * Should match rcu_assign_pointer() or rcu_xchg_pointer().
+ *
+ * This macro is less than 10 lines long.  The intent is that this macro
+ * meets the 10-line criterion in LGPL, allowing this function to be
+ * expanded directly in non-LGPL code.
  */
-
-#define _rcu_dereference(p)     ({					\
+#define _rcu_dereference(p)						\
+				__extension__				\
+				({					\
 				__typeof__(p) _________p1 = CMM_LOAD_SHARED(p); \
 				cmm_smp_read_barrier_depends();		\
 				(_________p1);				\
@@ -73,9 +78,13 @@ extern "C" {
  * data structure, which can be safely freed after waiting for a quiescent state
  * using synchronize_rcu(). If fails (unexpected value), returns old (which
  * should not be freed !).
+ *
+ * This macro is less than 10 lines long.  The intent is that this macro
+ * meets the 10-line criterion in LGPL, allowing this function to be
+ * expanded directly in non-LGPL code.
  */
-
 #define _rcu_cmpxchg_pointer(p, old, _new)				\
+	__extension__							\
 	({								\
 		__typeof__(*p) _________pold = (old);			\
 		__typeof__(*p) _________pnew = (_new);			\
@@ -89,9 +98,13 @@ extern "C" {
  * _rcu_xchg_pointer - same as rcu_assign_pointer, but returns the previous
  * pointer to the data structure, which can be safely freed after waiting for a
  * quiescent state using synchronize_rcu().
+ *
+ * This macro is less than 10 lines long.  The intent is that this macro
+ * meets the 10-line criterion in LGPL, allowing this function to be
+ * expanded directly in non-LGPL code.
  */
-
 #define _rcu_xchg_pointer(p, v)				\
+	__extension__					\
 	({						\
 		__typeof__(*p) _________pv = (v);	\
 		if (!__builtin_constant_p(v) ||		\
@@ -120,12 +133,15 @@ extern "C" {
  * them. It also makes sure the compiler does not reorder code initializing the
  * data structure before its publication.
  *
- * Should match rcu_dereference_pointer().
+ * Should match rcu_dereference().
+ *
+ * This macro is less than 10 lines long.  The intent is that this macro
+ * meets the 10-line criterion in LGPL, allowing this function to be
+ * expanded directly in non-LGPL code.
  */
-
 #define _rcu_assign_pointer(p, v)	_rcu_set_pointer(&(p), v)
 
-#ifdef __cplusplus 
+#ifdef __cplusplus
 }
 #endif