Re: code pattern for locking & unlocking
On 25 nov, 23:48, Daniel Anderson <woni...@gmail.com> wrote:
Hi!
I often have to acquire locks and release them after I'm finished with
them.
I use constructor/destructor to acquire & release locks. everything
works fine.
sometime I must acquire a lock for few instructions, then release it
in the middle of a big function. I use braces to get timely
destructors, but I find the "middle of nowhere" braces kind of
embarrassing.
Really ?
Sometimes I use them to separated unrelated sections of a function
body:
void foo()
{
{ // do foo
...
}
{ // do bar
...
}
}
something like:
struct Lock
{
Lock(Mutex& mtx) mtx_(mtx) { mtx.lock(); }
~Lock() { mtx_.unlock(); }
operator bool() { return true;}
};
void someFunc()
{
// do some stuff
...
// now time to update share data
{
Lock myLock(data_mutex);
//use locked data
....
} // destructor called
// do more stuff
...
}
I would like to have something like the using keyword in c#.
Is there a way to fake it in C++ ?
If you really want to do it. You could always use a macro but IMO it
would be dangerous.
for now I'm using an if to do it.
void someFunc()
{
// do some stuff
...
// now time to update share data
if (Lock myLock = Lock(data_mutex))
{
//use locked data
....
} // Unlock done by destructor
// do more stuff
...
}
Is it good programming ?
Is there a better way ?
Why not simply align the opening parenthesis with the lock:
{ Lock myLock(mutex)
...
}
--
Michael
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