Memory leaks when generating dispatch source timer events - iphone

Question

We are using dispatch queues to generate timer events. Following is the code which does the task:
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue);
if (!timer) return self;
dispatch_source_set_timer(timer, dispatch_walltime(NULL, 0), interval * NSEC_PER_SEC, 5 * NSEC_PER_SEC);
dispatch_source_set_event_handler(timer,
^{
//Some work…
});
This works very well except that when we run the profiler, we see a lot of memory leaks from these methods:
dispatch_source_create
dispatch_source_set_timer
dispatch_source_set_event_handler
We had made sure that timer is released using dispatch_release() method.
Can someone please let us know if there is any mistake we are doing in the code above? And also if you can point out any example of timer event generation, it would be helpful.

Answer 1

dispatch_source_set_timer(3) Mac OS X Manual Page
All timers will repeat indefinitely until
dispatch_source_cancel() is called.
How do you call dispatch_source_cancel() and dispatch_release() for the timer?
Dispatch source timer example:
dispatch_source_t timer = dispatch_source_create(
DISPATCH_SOURCE_TYPE_TIMER, 0, 0,
dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0));
dispatch_source_set_timer(timer,
dispatch_time(DISPATCH_TIME_NOW, 1ull * NSEC_PER_SEC),
DISPATCH_TIME_FOREVER, 1ull * NSEC_PER_SEC);
dispatch_source_set_event_handler(timer, ^{
NSLog(#"wakeup!");
dispatch_source_cancel(timer);
});
dispatch_source_set_cancel_handler(timer, ^{
NSLog(#"canceled");
dispatch_release(timer);
});
dispatch_resume(timer);