*: 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, 2 insertions, 2 deletions

diff --git a/ospf6d/ospf6_lsa.c b/ospf6d/ospf6_lsa.c
index bea153c928..3ae368f1d0 100644
--- a/ospf6d/ospf6_lsa.c
+++ b/ospf6d/ospf6_lsa.c
@@ -722,8 +722,8 @@ ospf6_lsa_refresh (struct thread *thread)
 
   new = ospf6_lsa_create (self->header);
   new->lsdb = old->lsdb;
-  new->refresh = thread_add_timer (master, ospf6_lsa_refresh, new,
-                                   OSPF_LS_REFRESH_TIME);
+  new->refresh = thread_add_timer(master, ospf6_lsa_refresh, new,
+                                  OSPF_LS_REFRESH_TIME, NULL);
 
   /* store it in the LSDB for self-originated LSAs */
   ospf6_lsdb_add (ospf6_lsa_copy (new), lsdb_self);