Adds trunk/talk folder of revision 359 from libjingles google code to
trunk/talk


git-svn-id: http://webrtc.googlecode.com/svn/trunk@4318 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/base/taskrunner.h b/talk/base/taskrunner.h
new file mode 100644
index 0000000..f34a609
--- /dev/null
+++ b/talk/base/taskrunner.h
@@ -0,0 +1,117 @@
+/*
+ * libjingle
+ * Copyright 2004--2006, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef TALK_BASE_TASKRUNNER_H__
+#define TALK_BASE_TASKRUNNER_H__
+
+#include <vector>
+
+#include "talk/base/basictypes.h"
+#include "talk/base/sigslot.h"
+#include "talk/base/taskparent.h"
+
+namespace talk_base {
+class Task;
+
+const int64 kSecToMsec = 1000;
+const int64 kMsecTo100ns = 10000;
+const int64 kSecTo100ns = kSecToMsec * kMsecTo100ns;
+
+class TaskRunner : public TaskParent, public sigslot::has_slots<> {
+ public:
+  TaskRunner();
+  virtual ~TaskRunner();
+
+  virtual void WakeTasks() = 0;
+
+  // Returns the current time in 100ns units.  It is used for
+  // determining timeouts.  The origin is not important, only
+  // the units and that rollover while the computer is running.
+  //
+  // On Windows, GetSystemTimeAsFileTime is the typical implementation.
+  virtual int64 CurrentTime() = 0 ;
+
+  void StartTask(Task *task);
+  void RunTasks();
+  void PollTasks();
+
+  void UpdateTaskTimeout(Task *task, int64 previous_task_timeout_time);
+
+#ifdef _DEBUG
+  bool is_ok_to_delete(Task* task) {
+    return task == deleting_task_;
+  }
+
+  void IncrementAbortCount() {
+    ++abort_count_;
+  }
+
+  void DecrementAbortCount() {
+    --abort_count_;
+  }
+#endif
+
+  // Returns the next absolute time when a task times out
+  // OR "0" if there is no next timeout.
+  int64 next_task_timeout() const;
+
+ protected:
+  // The primary usage of this method is to know if
+  // a callback timer needs to be set-up or adjusted.
+  // This method will be called
+  //  * when the next_task_timeout() becomes a smaller value OR
+  //  * when next_task_timeout() has changed values and the previous
+  //    value is in the past.
+  //
+  // If the next_task_timeout moves to the future, this method will *not*
+  // get called (because it subclass should check next_task_timeout()
+  // when its timer goes off up to see if it needs to set-up a new timer).
+  //
+  // Note that this maybe called conservatively.  In that it may be
+  // called when no time change has happened.
+  virtual void OnTimeoutChange() {
+    // by default, do nothing.
+  }
+
+ private:
+  void InternalRunTasks(bool in_destructor);
+  void CheckForTimeoutChange(int64 previous_timeout_time);
+
+  std::vector<Task *> tasks_;
+  Task *next_timeout_task_;
+  bool tasks_running_;
+#ifdef _DEBUG
+  int abort_count_;
+  Task* deleting_task_;
+#endif
+
+  void RecalcNextTimeout(Task *exclude_task);
+};
+
+} // namespace talk_base
+
+#endif  // TASK_BASE_TASKRUNNER_H__