From: Yuval Ronen (ronen_yuval_at_[hidden])
Date: 2007-05-07 00:14:44
Gregory Dai wrote:
> On 5/6/07, Yuval Ronen <ronen_yuval_at_[hidden]> wrote:
>
> <snip>
>
> namespace boost {
>> class semaphore
>> {
>> public:
>> semaphore(std::size_t count) : m_count(count), m_mutex(),
>> m_condition() { }
>>
>> void lock()
>> {
>> mutex::scoped_lock sl(m_mutex);
>> while (m_count == 0)
>> m_condition.wait(sl);
>> assert(m_count > 0);
>> m_count--;
>> }
>>
>> void unlock()
>> {
>> mutex::scoped_lock sl(m_mutex);
>> m_count++;
>> m_condition.notify_one();
>> }
>>
>> private:
>> std::size_t m_count;
>> mutex m_mutex;
>> condition m_condition;
>> };
>>
>> } // namespace boost
>
>
> <snip>
>
> Could we use more conventional method names such as wait() and post()
> instead of lock() and unlock(), please? Even acquire() and release() sound
> better. In addition, I'd suggest two more member methods:
> try_wait/try_acquire(size_t timeout) and count().
lock() and unlock() are good for usage with scoped_lock (in the code I
posted I actually didn't use the semaphore with a scoped_lock, but I
think it's a common use case). As far as the additions you suggest - I
probably didn't wrote a full fledged semaphore, just what I needed to
implement the stuff I needed. I agree that if it makes it to be publicly
available, these edges should be smoothed.