Merged win-pollable-condition branch changes 743545:746056 into trunk

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@746061 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 25 insertions, 21 deletions

diff --git a/cpp/src/qpid/sys/PollableQueue.h b/cpp/src/qpid/sys/PollableQueue.h
index b5ff98c2c7..a23cc5137a 100644
--- a/cpp/src/qpid/sys/PollableQueue.h
+++ b/cpp/src/qpid/sys/PollableQueue.h
@@ -23,8 +23,6 @@
  */
 
 #include "qpid/sys/PollableCondition.h"
-#include "qpid/sys/Dispatcher.h"
-#include "qpid/sys/DispatchHandle.h"
 #include "qpid/sys/Monitor.h"
 #include "qpid/sys/Thread.h"
 #include <boost/function.hpp>
@@ -38,9 +36,10 @@ namespace sys {
 class Poller;
 
 /**
- * A queue that can be polled by sys::Poller.  Any thread can push to
- * the queue, on wakeup the poller thread processes all items on the
- * queue by passing them to a callback in a batch.
+ * A queue whose item processing is dispatched by sys::Poller.
+ * Any thread can push to the queue; items pushed trigger an event the Poller
+ * recognizes. When a Poller I/O thread dispatches the event, a
+ * user-specified callback is invoked with all items on the queue.
  */
 template <class T>
 class PollableQueue {
@@ -50,12 +49,21 @@ class PollableQueue {
 
     /**
      * Callback to process a batch of items from the queue.
-     * @param values to process, any items remaining after call are put back on the queue.
+     *
+     * @param values  Queue of values to process. Any items remaining
+     *                on return from Callback are put back on the queue.
      */
     typedef boost::function<void (Queue& values)> Callback;
 
-    /** When the queue is selected by the poller, values are passed to callback cb. */
-    PollableQueue(const Callback& cb, const boost::shared_ptr<sys::Poller>& poller);
+    /**
+     * Constructor; sets necessary parameters.
+     *
+     * @param cb      Callback that will be called to process items on the
+     *                queue. Will be called from a Poller I/O thread.
+     * @param poller  Poller to use for dispatching queue events.
+     */
+    PollableQueue(const Callback& cb,
+                  const boost::shared_ptr<sys::Poller>& poller);
 
     ~PollableQueue();
     
@@ -85,14 +93,12 @@ class PollableQueue {
     typedef sys::Monitor::ScopedLock ScopedLock;
     typedef sys::Monitor::ScopedUnlock ScopedUnlock;
 
-    void dispatch(sys::DispatchHandle&);
+    void dispatch(PollableCondition& cond);
     void process();
     
     mutable sys::Monitor lock;
     Callback callback;
-    boost::shared_ptr<sys::Poller> poller;
     PollableCondition condition;
-    DispatchHandleRef handle;
     Queue queue, batch;
     Thread dispatcher;
     bool stopped;
@@ -100,11 +106,10 @@ class PollableQueue {
 
 template <class T> PollableQueue<T>::PollableQueue(
     const Callback& cb, const boost::shared_ptr<sys::Poller>& p) 
-    : callback(cb), poller(p),
-      handle(condition, boost::bind(&PollableQueue<T>::dispatch, this, _1), 0, 0), stopped(true)
+  : callback(cb),
+    condition(boost::bind(&PollableQueue<T>::dispatch, this, _1), p),
+    stopped(true)
 {
-    handle.startWatch(poller);
-    handle.unwatch();
 }
 
 template <class T> void PollableQueue<T>::start() {
@@ -112,11 +117,10 @@ template <class T> void PollableQueue<T>::start() {
     if (!stopped) return;
     stopped = false;
     if (!queue.empty()) condition.set();
-    handle.rewatch();
+    condition.rearm();
 }
 
 template <class T> PollableQueue<T>::~PollableQueue() {
-    handle.stopWatch();
 }
 
 template <class T> void PollableQueue<T>::push(const T& t) {
@@ -125,15 +129,15 @@ template <class T> void PollableQueue<T>::push(const T& t) {
     queue.push_back(t);
 }
 
-template <class T> void PollableQueue<T>::dispatch(sys::DispatchHandle& h) {
+template <class T> void PollableQueue<T>::dispatch(PollableCondition& cond) {
     ScopedLock l(lock);
     assert(dispatcher.id() == 0);
     dispatcher = Thread::current();
     process();
     dispatcher = Thread();
-    if (queue.empty()) condition.clear();
+    if (queue.empty()) cond.clear();
     if (stopped) lock.notifyAll();
-    else h.rewatch();
+    else cond.rearm();
 }
 
 template <class T> void PollableQueue<T>::process() {
@@ -159,7 +163,7 @@ template <class T> void PollableQueue<T>::shutdown() {
 template <class T> void PollableQueue<T>::stop() {
     ScopedLock l(lock);
     if (stopped) return;
-    handle.unwatch();
+    condition.disarm();
     stopped = true;
     // Avoid deadlock if stop is called from the dispatch thread
     while (dispatcher.id() && dispatcher.id() != Thread::current().id())