[checkmk-commits] ClientQueue uses condition_variable now, fixing a bug with spurious wakeups.

Module: check_mk Branch: master Commit: ff3d5b68a202b49f6558081ad0c78f81af4f5ca6 URL: http://git.mathias-kettner.de/git/?p=check_mk.git;a=commit;h=ff3d5b68a202b4… Author: Sven Panne &lt;sp(a)mathias-kettner.de&gt; Date: Wed Nov 18 11:07:07 2015 +0100 ClientQueue uses condition_variable now, fixing a bug with spurious wakeups. Made all fields private on the way. --- livestatus/src/ClientQueue.cc | 33 ++++++++++++--------------------- livestatus/src/ClientQueue.h | 12 ++++++------ 2 files changed, 18 insertions(+), 27 deletions(-) diff --git a/livestatus/src/ClientQueue.cc b/livestatus/src/ClientQueue.cc index 7e44ec2..ab81bac 100644 --- a/livestatus/src/ClientQueue.cc +++ b/livestatus/src/ClientQueue.cc @@ -24,52 +24,43 @@ #include "ClientQueue.h" #include <unistd.h> +#include <algorithm> using mk::lock_guard; using mk::mutex; +using mk::unique_lock; +using std::for_each; ClientQueue::ClientQueue() { - pthread_cond_init(&_signal, 0); } ClientQueue::~ClientQueue() { - for (_queue_t::iterator it = _queue.begin(); - it != _queue.end(); - ++it) - { - close(*it); - } - pthread_cond_destroy(&_signal); + for_each(_queue.begin(), _queue.end(), close); } void ClientQueue::addConnection(int fd) { { - lock_guard<mutex> lg(_lock); + lock_guard<mutex> lg(_mutex); _queue.push_back(fd); } - pthread_cond_signal(&_signal); + _cond.notify_one(); } int ClientQueue::popConnection() { - lock_guard<mutex> lg(_lock); - if (_queue.size() == 0) { - pthread_cond_wait(&_signal, _lock.native_handle()); - } - - int fd = -1; - if (_queue.size() > 0) { - fd = _queue.front(); - _queue.pop_front(); - } + unique_lock<mutex> ul(_mutex); + while (_queue.empty()) _cond.wait(ul); + int fd = _queue.front(); + _queue.pop_front(); return fd; } +// Note: What we *really* want here is the functionality of notify_all_at_thread_exit. void ClientQueue::wakeupAll() { - pthread_cond_broadcast(&_signal); + _cond.notify_all(); } diff --git a/livestatus/src/ClientQueue.h b/livestatus/src/ClientQueue.h index 0a9bea0..b8a0584 100644 --- a/livestatus/src/ClientQueue.h +++ b/livestatus/src/ClientQueue.h @@ -26,24 +26,24 @@ #define ClientQueue_h #include "config.h" // IWYU pragma: keep -#include <pthread.h> #include <deque> #include <memory> +#include "ConditionVariable.h" #include "Mutex.h" class ClientQueue { - typedef std::deque<int> _queue_t; - _queue_t _queue; public: ClientQueue(); ~ClientQueue(); void addConnection(int); int popConnection(); void wakeupAll(); - - mk::mutex _lock; - pthread_cond_t _signal; +private: + typedef std::deque<int> _queue_t; + _queue_t _queue; + mk::mutex _mutex; + mk::condition_variable _cond; }; #endif // ClientQueue_h