thread safety

src/condition_variable.hpp

@@ -0,0 +1,149 @@
+/*
+    Copyright (c) 2007-2015 Contributors as noted in the AUTHORS file
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __ZMQ_CONDITON_VARIABLE_HPP_INCLUDED__
+#define __ZMQ_CONDITON_VARIABLE_HPP_INCLUDED__
+
+#include "platform.hpp"
+#include "err.hpp"
+#include "mutex.hpp"
+
+//  Condition variable class encapsulates OS mutex in a platform-independent way.
+
+#ifdef ZMQ_HAVE_WINDOWS
+
+#include "windows.hpp"
+
+namespace zmq
+{
+
+    class condition_variable_t
+    {
+    public:
+        inline condition_variable_t ()
+        {
+            InitializeConditionVariable (&cv);
+        }
+
+        inline ~condition_variable_t ()
+        {
+            
+        }
+
+        inline int wait (mutex_t* mutex_, int timeout_ )
+        {
+            int rc = SleepConditionVariableCS(&cv, mutex_->get_cs (), timeout_);
+
+            if (rc != 0)
+                return 0;
+
+            rc = GetLastError();
+
+            if (rc != ERROR_TIMEOUT)
+                win_assert(rc);
+
+            errno = EAGAIN;            
+            return -1;
+        }
+
+        inline void broadcast ()
+        {
+            WakeAllConditionVariable(&cv);
+        }
+
+    private:
+
+        CONDITION_VARIABLE cv;
+
+        //  Disable copy construction and assignment.
+        condition_variable_t (const condition_variable_t&);
+        void operator = (const condition_variable_t&);
+    };
+
+}
+
+#else
+
+#include <pthread.h>
+
+namespace zmq
+{
+
+    class condition_variable_t
+    {
+    public:
+        inline condition_variable_t ()
+        {
+            int rc = pthread_cond_init (&cond, NULL);
+            posix_assert (rc);
+        }
+
+        inline ~condition_variable_t ()
+        {
+            int rc = pthread_cond_destroy (&cond);
+            posix_assert (rc);
+        }
+
+        inline int wait (mutex_t* mutex_, int timeout_)
+        {
+            int rc;
+
+            if (timeout_ != -1) {
+                struct timespec timeout;
+                clock_gettime(CLOCK_REALTIME, &timeout);
+    
+                timeout.tv_sec += timeout_ / 1000;
+                timeout.tv_nsec += (timeout_ % 1000) * 1000000; 
+                rc = pthread_cond_timedwait (&cond, mutex_->get_mutex (), &timeout);
+            }
+            else
+                rc = pthread_cond_wait(&cond, mutex_->get_mutex());
+
+            if (rc == 0)
+                return 0;
+
+            if (rc == ETIMEDOUT){
+                errno= EAGAIN;
+                return -1;
+            }
+
+            posix_assert (rc);
+            return -1;
+        }
+
+        inline void broadcast ()
+        {
+            int rc = pthread_cond_broadcast (&cond);
+            posix_assert (rc);
+        }
+
+    private:
+
+        pthread_cond_t cond;
+
+        // Disable copy construction and assignment.
+        condition_variable_t (const condition_variable_t&);
+        const condition_variable_t &operator = (const condition_variable_t&);
+    };
+}
+
+#endif
+
+
+#endif