On Tue, 14 May 2013 13:59:51 -0400, Heinz <thor...@gmail.com> wrote:
Guys, this is a precise example of what i'm trying to do. You'll notice
that there're 2 ways of waking up the consumer:
2 things:
1. D mutex locks are re-entrant. That is, you can do:
synchronized(mutex)
{
synchronized(mutex)
{
...
}
}
and all is fine.
2. The condition logic in your code is wrong. The condition/mutex
protects the messages being sent to the consumer.
It seems that you have two messages (which is OK):
- my_variable is present, needs to be processed
- Run function 2 (flag loop == run function 2), set from inside the
consumer, and some undisclosed threads. I find this logic rather
dangerous, but it is your app, I have no idea of the real meaning :)
So I would do it like this (names TBD based on your real use case)
void SetLoop(bool yesOrNo)
{
synchronized(cond.mutex)
{
if((loop = yesOrNo) == true)
cond.notify();
}
}
void MyConsumer()
{
while(true)
{
Object _my_variable = null;
synchronized(cond.mutex)
{
while(!loop && my_variable is null) // always wait for *real* messages
to be set
cond.wait();
_my_variable = my_variable;
my_variable = null; // consume
}
// process local consumed copy of _my_variable *outside* of lock
if(_my_variable !is null)
{
/*
...
Call private function 1. SetLoop(true/false) might be
called here.
...
*/
}
// These conditions are intentionally placed here.
synchronized(cond.mutex)
{
if(loop == false)
continue; // Jump to next iteration. Please note that cond.mutex gets
released and reaquired in the next iteration.
else
loop = false; // Reset waiting on every iteration. Can be modified by
private function 2 below.
}
/*
...
Call private function 2. SetLoop(true/false) might be called
here.
...
*/
}
}
Then everything should be good. I'd also add a "SetMyVariable" function
too, akin to SetLoop.
-Steve
