*: 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, 1 insertions, 1 deletions

diff --git a/ospf6d/ospf6d.c b/ospf6d/ospf6d.c
index aa219c780..793397570 100644
--- a/ospf6d/ospf6d.c
+++ b/ospf6d/ospf6d.c
@@ -1252,7 +1252,7 @@ ospf6_init (void)
 
   /* Make ospf protocol socket. */
   ospf6_serv_sock ();
-  thread_add_read (master, ospf6_receive, NULL, ospf6_sock);
+  thread_add_read(master, ospf6_receive, NULL, ospf6_sock, NULL);
 }
 
 void