Re: [Xenomai-core] [PATCH] Fixs doxygen doc on rt_queue_read in ksrc/native/queue.c (for SVN version)

[Jan Kiszka <jan.kiszka@domain.hid>]

[-- Attachment #1.1: Type: text/plain, Size: 1195 bytes --]

[a few interruptions later]

Jan Kiszka wrote:
> Rodrigo Rosenfeld Rosas wrote:
>> BTW, please, could someone confirm the rt_task_delete(NULL) bug in SVN?
> 
> Half-confirmed, there is something fishy. I'm struggling with the
> debugger ATM, not sure yet who's wrong ;). It tells me rt_task_delete of
> the skin module is entered with task != NULL...

...which turns out to be fine, just appears redundant to me when
comparing __rt_task_delete and rt_task_delete for the task=NULL case.

Anyway, leaving a native task with rt_task_delete(NULL) raises SIGKILL
to the whole process instead of just the task (pthread). This lets your
program terminate unexpectedly - I would say: a bug. And this doesn't
happen with 2.1?

I guess the easiest way to solve this is to catch NULL in userspace and
call pthread_exit() in favour of the skin service (the POSIX skin uses
pthread_exit anyway), see attached patch. Someone just has to confirm
that there will be no problem hidden by this approach.

Jan


PS: What's the reason for "if (err == -ESRCH) return 0" in
src/skins/native/task.c, rt_task_delete? Why is that error generate in
the first place if it is zeroed out here?

[-- Attachment #1.2: task-delete-null.patch --]
[-- Type: text/plain, Size: 456 bytes --]

Index: src/skins/native/task.c
===================================================================
--- src/skins/native/task.c	(revision 923)
+++ src/skins/native/task.c	(working copy)
@@ -212,7 +212,10 @@ int rt_task_delete (RT_TASK *task)
 {
     int err;
 
-    if (task && task->opaque2) {
+    if (!task)
+	pthread_exit(NULL);
+
+    if (task->opaque2) {
 	err = pthread_cancel((pthread_t)task->opaque2);
 	if (err)
 	    return -err;

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 250 bytes --]