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--- a/sc2src/workqueue.h
+++ b/sc2src/workqueue.h
@@ -1,38 +1,31 @@
-/*	 Copyright (C) 2012 J.F.Dockes
- *	 This program is free software; you can redistribute it and/or modify
- *	 it under the terms of the GNU General Public License as published by
- *	 the Free Software Foundation; either version 2 of the License, or
- *	 (at your option) any later version.
+/*   Copyright (C) 2012-2016 J.F.Dockes
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
  *
- *	 This program 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 General Public License for more details.
+ *   This program 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 General Public License for more details.
  *
- *	 You should have received a copy of the GNU General Public License
- *	 along with this program; if not, write to the
- *	 Free Software Foundation, Inc.,
- *	 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the
+ *   Free Software Foundation, Inc.,
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  */
 #ifndef _WORKQUEUE_H_INCLUDED_
 #define _WORKQUEUE_H_INCLUDED_
 
-#include <pthread.h>
-#include <time.h>
-
+#include <thread>
+#include <future>
 #include <string>
 #include <queue>
-#include <unordered_map>
-
-#include "ptmutex.h"
-
-/// Store per-worker-thread data. Just an initialized timespec, and
-/// used at the moment.
-class WQTData {
-public:
-    WQTData() {wstart.tv_sec = 0; wstart.tv_nsec = 0;}
-    struct timespec wstart;
-};
+#include <list>
+#include <mutex>
+#include <condition_variable>
+
+#include "log.h"
 
 /**
  * A WorkQueue manages the synchronisation around a queue of work items,
@@ -46,6 +39,10 @@
  * the client or worker sets an end condition on the queue. A second
  * queue could conceivably be used for returning individual task
  * status.
+ *
+ * The strange thread functions argument and return values
+ * comes from compatibility with an earlier pthread-based
+ * implementation.
  */
 template <class T> class WorkQueue {
 public:
@@ -53,81 +50,79 @@
     /** Create a WorkQueue
      * @param name for message printing
      * @param hi number of tasks on queue before clients blocks. Default 0
-     *	  meaning no limit. hi == -1 means that the queue is disabled.
+     *    meaning no limit. hi == -1 means that the queue is disabled.
      * @param lo minimum count of tasks before worker starts. Default 1.
      */
     WorkQueue(const std::string& name, size_t hi = 0, size_t lo = 1)
-        : m_name(name), m_high(hi), m_low(lo),
-          m_workers_exited(0), m_clients_waiting(0), m_workers_waiting(0),
-          m_tottasks(0), m_nowake(0), m_workersleeps(0), m_clientsleeps(0)
-	{
-            m_ok = (pthread_cond_init(&m_ccond, 0) == 0) &&
-                (pthread_cond_init(&m_wcond, 0) == 0);
-	}
-
-    ~WorkQueue()
-	{
-            if (!m_worker_threads.empty())
-                setTerminateAndWait();
-	}
+        : m_name(name), m_high(hi), m_low(lo), m_workers_exited(0),
+          m_ok(true), m_clients_waiting(0), m_workers_waiting(0),
+          m_tottasks(0), m_nowake(0), m_workersleeps(0), m_clientsleeps(0) {
+    }
+
+    ~WorkQueue() {
+        if (!m_worker_threads.empty()) {
+            setTerminateAndWait();
+        }
+    }
 
     /** Start the worker threads.
      *
      * @param nworkers number of threads copies to start.
      * @param start_routine thread function. It should loop
-     *	  taking (WorkQueue::take()) and executing tasks.
+     *      taking (QueueWorker::take()) and executing tasks.
      * @param arg initial parameter to thread function.
      * @return true if ok.
      */
-    bool start(int nworkers, void *(*workproc)(void *), void *arg)
-	{
-            PTMutexLocker lock(m_mutex);
-            for	 (int i = 0; i < nworkers; i++) {
-                int err;
-                pthread_t thr;
-                if ((err = pthread_create(&thr, 0, workproc, arg))) {
-                    return false;
-                }
-                m_worker_threads.insert(std::pair<pthread_t, WQTData>(thr, WQTData()));
-            }
-            return true;
-	}
+    bool start(int nworkers, void *(workproc)(void *), void *arg) {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        for (int i = 0; i < nworkers; i++) {
+            std::packaged_task<void *(void *)> task(workproc);
+            Worker w;
+            w.res = task.get_future();
+            w.thr = std::thread(std::move(task), arg);
+            m_worker_threads.push_back(std::move(w));
+        }
+        return true;
+    }
 
     /** Add item to work queue, called from client.
      *
      * Sleeps if there are already too many.
      */
-    bool put(T t, bool flushprevious = false)
-	{
-            PTMutexLocker lock(m_mutex);
-            if (!lock.ok() || !ok()) {
+    bool put(T t, bool flushprevious = false) {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        if (!ok()) {
+            LOGERR("WorkQueue::put:"  << m_name << ": !ok\n");
+            return false;
+        }
+
+        while (ok() && m_high > 0 && m_queue.size() >= m_high) {
+            m_clientsleeps++;
+            // Keep the order: we test ok() AFTER the sleep...
+            m_clients_waiting++;
+            m_ccond.wait(lock);
+            if (!ok()) {
+                m_clients_waiting--;
                 return false;
             }
-
-            while (ok() && m_high > 0 && m_queue.size() >= m_high) {
-                m_clientsleeps++;
-                // Keep the order: we test ok() AFTER the sleep...
-                m_clients_waiting++;
-                if (pthread_cond_wait(&m_ccond, lock.getMutex()) || !ok()) {
-                    m_clients_waiting--;
-                    return false;
-                }
-                m_clients_waiting--;
-            }
-            if (flushprevious) {
-                while (!m_queue.empty())
-                    m_queue.pop();
-            }
-            m_queue.push(t);
-            if (m_workers_waiting > 0) {
-                // Just wake one worker, there is only one new task.
-                pthread_cond_signal(&m_wcond);
-            } else {
-                m_nowake++;
-            }
-
-            return true;
-	}
+            m_clients_waiting--;
+        }
+        if (flushprevious) {
+            while (!m_queue.empty()) {
+                m_queue.pop();
+            }
+        }
+
+        m_queue.push(t);
+        if (m_workers_waiting > 0) {
+            // Just wake one worker, there is only one new task.
+            m_wcond.notify_one();
+        } else {
+            m_nowake++;
+        }
+
+        return true;
+    }
 
     /** Wait until the queue is inactive. Called from client.
      *
@@ -145,127 +140,128 @@
      * of suspend condition was set on the queue by waitIdle(), to be reset by
      * some kind of "resume" call. Not currently the case.
      */
-    bool waitIdle()
-	{
-            PTMutexLocker lock(m_mutex);
-            if (!lock.ok() || !ok()) {
-                return false;
-            }
-
-            // We're done when the queue is empty AND all workers are back
-            // waiting for a task.
-            while (ok() && (m_queue.size() > 0 ||
-                            m_workers_waiting != m_worker_threads.size())) {
-                m_clients_waiting++;
-                if (pthread_cond_wait(&m_ccond, lock.getMutex())) {
-                    m_clients_waiting--;
-                    m_ok = false;
-                    return false;
-                }
-                m_clients_waiting--;
-            }
-
-            return ok();
-	}
-
+    bool waitIdle() {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        if (!ok()) {
+            LOGERR("WorkQueue::waitIdle:"  << m_name << ": not ok\n");
+            return false;
+        }
+
+        // We're done when the queue is empty AND all workers are back
+        // waiting for a task.
+        while (ok() && (m_queue.size() > 0 ||
+                        m_workers_waiting != m_worker_threads.size())) {
+            m_clients_waiting++;
+            m_ccond.wait(lock);
+            m_clients_waiting--;
+        }
+
+        return ok();
+    }
 
     /** Tell the workers to exit, and wait for them.
      *
      * Does not bother about tasks possibly remaining on the queue, so
      * should be called after waitIdle() for an orderly shutdown.
      */
-    void* setTerminateAndWait()
-	{
-            PTMutexLocker lock(m_mutex);
-
-            if (m_worker_threads.empty()) {
-                // Already called ?
-                return (void*)0;
-            }
-
-            // Wait for all worker threads to have called workerExit()
-            m_ok = false;
-            while (m_workers_exited < m_worker_threads.size()) {
-                pthread_cond_broadcast(&m_wcond);
-                m_clients_waiting++;
-                if (pthread_cond_wait(&m_ccond, lock.getMutex())) {
-                    m_clients_waiting--;
-                    return (void*)0;
-                }
-                m_clients_waiting--;
-            }
-
-            // Perform the thread joins and compute overall status
-            // Workers return (void*)1 if ok
-            void *statusall = (void*)1;
-            std::unordered_map<pthread_t,  WQTData>::iterator it;
-            while (!m_worker_threads.empty()) {
-                void *status;
-                it = m_worker_threads.begin();
-                pthread_join(it->first, &status);
-                if (status == (void *)0)
-                    statusall = status;
-                m_worker_threads.erase(it);
-            }
-
-            // Reset to start state.
-            m_workers_exited = m_clients_waiting = m_workers_waiting =
+    void *setTerminateAndWait() {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        LOGDEB("setTerminateAndWait:"  << m_name << "\n");
+
+        if (m_worker_threads.empty()) {
+            // Already called ?
+            return (void*)0;
+        }
+
+        // Wait for all worker threads to have called workerExit()
+        m_ok = false;
+        while (m_workers_exited < m_worker_threads.size()) {
+            m_wcond.notify_all();
+            m_clients_waiting++;
+            m_ccond.wait(lock);
+            m_clients_waiting--;
+        }
+
+        LOGINFO(""  << m_name << ": tasks "  << m_tottasks << " nowakes "  <<
+                m_nowake << " wsleeps "  << m_workersleeps << " csleeps "  <<
+                m_clientsleeps << "\n");
+        // Perform the thread joins and compute overall status
+        // Workers return (void*)1 if ok
+        void *statusall = (void*)1;
+        while (!m_worker_threads.empty()) {
+            void *status = m_worker_threads.front().res.get();
+            m_worker_threads.front().thr.join();
+            if (status == (void *)0) {
+                statusall = status;
+            }
+            m_worker_threads.pop_front();
+        }
+
+        // Reset to start state.
+        m_workers_exited = m_clients_waiting = m_workers_waiting =
                 m_tottasks = m_nowake = m_workersleeps = m_clientsleeps = 0;
-            m_ok = true;
-
-            return statusall;
-	}
+        m_ok = true;
+
+        LOGDEB("setTerminateAndWait:"  << m_name << " done\n");
+        return statusall;
+    }
 
     /** Take task from queue. Called from worker.
      *
      * Sleeps if there are not enough. Signal if we go to sleep on empty
      * queue: client may be waiting for our going idle.
      */
-    bool take(T* tp, size_t *szp = 0)
-	{
-            PTMutexLocker lock(m_mutex);
-            if (!lock.ok() || !ok()) {
+    bool take(T* tp, size_t *szp = 0) {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        if (!ok()) {
+            LOGDEB("WorkQueue::take:"  << m_name << ": not ok\n");
+            return false;
+        }
+
+        while (ok() && m_queue.size() < m_low) {
+            m_workersleeps++;
+            m_workers_waiting++;
+            if (m_queue.empty()) {
+                m_ccond.notify_all();
+            }
+            m_wcond.wait(lock);
+            if (!ok()) {
+                // !ok is a normal condition when shutting down
+                m_workers_waiting--;
                 return false;
             }
-
-            while (ok() && m_queue.size() < m_low) {
-                m_workersleeps++;
-                m_workers_waiting++;
-                if (m_queue.empty())
-                    pthread_cond_broadcast(&m_ccond);
-                if (pthread_cond_wait(&m_wcond, lock.getMutex()) || !ok()) {
-                    m_workers_waiting--;
-                    return false;
-                }
-                m_workers_waiting--;
-            }
-
-            m_tottasks++;
-            *tp = m_queue.front();
-            if (szp)
-                *szp = m_queue.size();
-            m_queue.pop();
-            if (m_clients_waiting > 0) {
-                // No reason to wake up more than one client thread
-                pthread_cond_signal(&m_ccond);
-            } else {
-                m_nowake++;
-            }
-            return true;
-	}
-    	
+            m_workers_waiting--;
+        }
+
+        m_tottasks++;
+        *tp = m_queue.front();
+        if (szp) {
+            *szp = m_queue.size();
+        }
+        m_queue.pop();
+        if (m_clients_waiting > 0) {
+            // No reason to wake up more than one client thread
+            m_ccond.notify_one();
+        } else {
+            m_nowake++;
+        }
+        return true;
+    }
+
     bool waitminsz(size_t sz) {
-        PTMutexLocker lock(m_mutex);
-        if (!lock.ok() || !ok()) {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        if (!ok()) {
             return false;
         }
 
         while (ok() && m_queue.size() < sz) {
             m_workersleeps++;
             m_workers_waiting++;
-            if (m_queue.empty())
-                pthread_cond_broadcast(&m_ccond);
-            if (pthread_cond_wait(&m_wcond, lock.getMutex()) || !ok()) {
+            if (m_queue.empty()) {
+                m_ccond.notify_all();
+            }
+            m_wcond.wait(lock);
+            if (!ok()) {
                 m_workers_waiting--;
                 return false;
             }
@@ -282,54 +278,57 @@
      * false by the shutdown code anyway). The thread must return/exit
      * immediately after calling this.
      */
-    void workerExit()
-	{
-            PTMutexLocker lock(m_mutex);
-            m_workers_exited++;
-            m_ok = false;
-            pthread_cond_broadcast(&m_ccond);
-	}
-
-    size_t qsize()
-	{
-            PTMutexLocker lock(m_mutex);
-            size_t sz = m_queue.size();
-            return sz;
-	}
+    void workerExit() {
+        LOGDEB("workerExit:"  << m_name << "\n");
+        std::unique_lock<std::mutex> lock(m_mutex);
+        m_workers_exited++;
+        m_ok = false;
+        m_ccond.notify_all();
+    }
+
+    size_t qsize() {
+        std::unique_lock<std::mutex> lock(m_mutex);
+        return m_queue.size();
+    }
 
 private:
-    bool ok()
-	{
-            bool isok = m_ok && m_workers_exited == 0 && !m_worker_threads.empty();
-            return isok;
-	}
-
-    long long nanodiff(const struct timespec& older,
-                       const struct timespec& newer)
-	{
-            return (newer.tv_sec - older.tv_sec) * 1000000000LL
-                + newer.tv_nsec - older.tv_nsec;
-	}
-
+    bool ok() {
+        bool isok = m_ok && m_workers_exited == 0 && !m_worker_threads.empty();
+        if (!isok) {
+            LOGDEB("WorkQueue:ok:" << m_name << ": not ok m_ok " << m_ok <<
+                   " m_workers_exited " << m_workers_exited <<
+                   " m_worker_threads size " << m_worker_threads.size() <<
+                   "\n");
+        }
+        return isok;
+    }
+
+    struct Worker {
+        std::thread         thr;
+        std::future<void *> res;
+    };
+    
     // Configuration
     std::string m_name;
     size_t m_high;
     size_t m_low;
 
+    // Worker threads having called exit. Used to decide when we're done
+    unsigned int m_workers_exited;
     // Status
-    // Worker threads having called exit
-    unsigned int m_workers_exited;
     bool m_ok;
 
-    // Per-thread data. The data is not used currently, this could be
-    // a set<pthread_t>
-    std::unordered_map<pthread_t, WQTData> m_worker_threads;
-
+    // Our threads. 
+    std::list<Worker> m_worker_threads;
+
+    // Jobs input queue
+    std::queue<T> m_queue;
+    
     // Synchronization
-    std::queue<T> m_queue;
-    pthread_cond_t m_ccond;
-    pthread_cond_t m_wcond;
-    PTMutexInit m_mutex;
+    std::condition_variable m_ccond;
+    std::condition_variable m_wcond;
+    std::mutex m_mutex;
+
     // Client/Worker threads currently waiting for a job
     unsigned int m_clients_waiting;
     unsigned int m_workers_waiting;
@@ -342,3 +341,4 @@
 };
 
 #endif /* _WORKQUEUE_H_INCLUDED_ */
+