*: remove THREAD_ON macros, add nullity check

The way thread.c is written, a caller who wishes to be able to cancel a
thread or avoid scheduling it twice must keep a reference to the thread.
Typically this is done with a long lived pointer whose value is checked
for null in order to know if the thread is currently scheduled.  The
check-and-schedule idiom is so common that several wrapper macros in
thread.h existed solely to provide it.

This patch removes those macros and adds a new parameter to all
thread_add_* functions which is a pointer to the struct thread * to
store the result of a scheduling call. If the value passed is non-null,
the thread will only be scheduled if the value is null. This helps with
consistency.

A Coccinelle spatch has been used to transform code of the form:

  if (t == NULL)
    t = thread_add_* (...)

to the form

  thread_add_* (..., &t)

The THREAD_ON macros have also been transformed to the underlying
thread.c calls.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 36 insertions, 36 deletions

diff --git a/bgpd/bgp_fsm.h b/bgpd/bgp_fsm.h
index 4d0b48f529..67ba387eb9 100644
--- a/bgpd/bgp_fsm.h
+++ b/bgpd/bgp_fsm.h
@@ -23,58 +23,58 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #define _QUAGGA_BGP_FSM_H
 
 /* Macro for BGP read, write and timer thread.  */
-#define BGP_READ_ON(T,F,V)			\
-  do {						\
-    if (!(T) && (peer->status != Deleted))	\
-      THREAD_READ_ON(bm->master,T,F,peer,V);	\
+#define BGP_READ_ON(T,F,V) \
+  do { \
+    if ((peer->status != Deleted)) \
+      thread_add_read (bm->master,(F),peer,(V),&(T)); \
   } while (0)
 
-#define BGP_READ_OFF(T)				\
-  do {						\
-    if (T)					\
-      THREAD_READ_OFF(T);			\
+#define BGP_READ_OFF(T) \
+  do { \
+    if (T) \
+      THREAD_READ_OFF(T); \
   } while (0)
 
-#define BGP_WRITE_ON(T,F,V)			\
-  do {						\
-    if (!(T) && (peer->status != Deleted))	\
-      THREAD_WRITE_ON(bm->master,(T),(F),peer,(V)); \
+#define BGP_WRITE_ON(T,F,V) \
+  do { \
+    if ((peer)->status != Deleted) \
+      thread_add_write (bm->master,(F),(peer),(V),&(T)); \
   } while (0)
 
-#define BGP_PEER_WRITE_ON(T,F,V, peer)			\
-  do {							\
-    if (!(T) && ((peer)->status != Deleted))		\
-      THREAD_WRITE_ON(bm->master,(T),(F),(peer),(V));	\
+#define BGP_PEER_WRITE_ON(T,F,V, peer) \
+  do { \
+    if ((peer)->status != Deleted) \
+      thread_add_write (bm->master,(F),(peer),(V),&(T)); \
   } while (0)
 
-#define BGP_WRITE_OFF(T)			\
-  do {						\
-    if (T)					\
-      THREAD_WRITE_OFF(T);			\
+#define BGP_WRITE_OFF(T) \
+  do { \
+    if (T) \
+      THREAD_WRITE_OFF(T); \
   } while (0)
 
-#define BGP_TIMER_ON(T,F,V)			\
-  do {						\
-    if (!(T) && (peer->status != Deleted))	\
-      THREAD_TIMER_ON(bm->master,(T),(F),peer,(V)); \
+#define BGP_TIMER_ON(T,F,V) \
+  do { \
+    if ((peer->status != Deleted)) \
+      thread_add_timer (bm->master,(F),peer,(V),&(T)); \
   } while (0)
 
-#define BGP_TIMER_OFF(T)			\
-  do {						\
-    if (T)					\
-      THREAD_TIMER_OFF(T);			\
+#define BGP_TIMER_OFF(T) \
+  do { \
+    if (T) \
+      THREAD_TIMER_OFF(T); \
   } while (0)
 
-#define BGP_EVENT_ADD(P,E)			\
-  do {						\
-    if ((P)->status != Deleted)			\
-      thread_add_event (bm->master, bgp_event, (P), (E)); \
+#define BGP_EVENT_ADD(P,E) \
+  do { \
+    if ((P)->status != Deleted) \
+      thread_add_event (bm->master, bgp_event, (P), (E), NULL); \
   } while (0)
 
-#define BGP_EVENT_FLUSH(P)			\
-  do { 						\
-    assert (peer); 				\
-    thread_cancel_event (bm->master, (P)); 		\
+#define BGP_EVENT_FLUSH(P) \
+  do { \
+    assert (peer); \
+    thread_cancel_event (bm->master, (P)); \
   } while (0)
 
 #define BGP_MSEC_JITTER 10