[niepce] Use std::unique_ptr<> for workers queue.

[Hubert Figuière <hub src gnome org>]

commit f19d3b86cea8e967dfec56b7b060092b2de4298c
Author: Hubert Figuière <hub figuiere net>
Date:   Mon Jun 17 20:07:16 2013 -0400

    Use std::unique_ptr<> for workers queue.

 src/engine/library/op.hpp                |   36 +++++++++++++++---------------
 src/engine/library/test_opqueue.cpp      |    9 +++++--
 src/engine/library/thumbnailcache.cpp    |    2 +-
 src/engine/library/thumbnailcache.hpp    |   10 ++++----
 src/fwk/utils/mtqueue.hpp                |   17 ++++++++++----
 src/fwk/utils/worker.hpp                 |   25 +++++++++++---------
 src/libraryclient/locallibraryserver.hpp |   12 +++++-----
 7 files changed, 62 insertions(+), 49 deletions(-)
---
diff --git a/src/engine/library/op.hpp b/src/engine/library/op.hpp
index 841fec0..6767422 100644
--- a/src/engine/library/op.hpp
+++ b/src/engine/library/op.hpp
@@ -1,7 +1,7 @@
 /*
  * niepce - engine/library/op.h
  *
- * Copyright (C) 2007-2009 Hubert Figuiere
+ * Copyright (C) 2007-2013 Hubert Figuiere
  *
  * 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
@@ -29,26 +29,26 @@
 
 namespace eng {
 
-       /** a library operation */
-       class Op
-       {
-       public:
-               typedef std::shared_ptr< Op > Ptr;
-               typedef std::function<void (const Library::Ptr &)> function_t;
+/** a library operation */
+class Op
+{
+public:
+    typedef std::unique_ptr< Op > Ptr;
+    typedef std::function<void (const Library::Ptr &)> function_t;
 
-               Op(tid_t id, const function_t & func);
+    Op(tid_t id, const function_t & func);
 
-               tid_t id() const 
-                       { return m_id; }
+    tid_t id() const
+        { return m_id; }
 
-        void operator() (const Library::Ptr &);
-               const function_t & fn() const
-                       { return m_function; }
-       protected:
-       private:
-               tid_t   m_id;
-               function_t m_function;
-       };
+    void operator() (const Library::Ptr &);
+    const function_t & fn() const
+        { return m_function; }
+protected:
+private:
+    tid_t   m_id;
+    function_t m_function;
+};
 
 }
 
diff --git a/src/engine/library/test_opqueue.cpp b/src/engine/library/test_opqueue.cpp
index 6a09168..8a30a65 100644
--- a/src/engine/library/test_opqueue.cpp
+++ b/src/engine/library/test_opqueue.cpp
@@ -41,13 +41,16 @@ int test_main(int, char *[])
 
        BOOST_CHECK(q.empty());
 
+       tid_t old_id = p->id();
+       Op* old_ptr = p.get();
        q.add(p);
        BOOST_CHECK(!q.empty());
+       BOOST_CHECK(p == nullptr);
 
        Op::Ptr p2(q.pop());
-       BOOST_CHECK(p2 == p);
-       BOOST_CHECK(p2->id() == p->id());
-       BOOST_CHECK(q.empty()); 
+       BOOST_CHECK(p2.get() == old_ptr);
+       BOOST_CHECK(p2->id() == old_id);
+       BOOST_CHECK(q.empty());
        return 0;
 }
 
diff --git a/src/engine/library/thumbnailcache.cpp b/src/engine/library/thumbnailcache.cpp
index 665ae41..67776d7 100644
--- a/src/engine/library/thumbnailcache.cpp
+++ b/src/engine/library/thumbnailcache.cpp
@@ -137,7 +137,7 @@ Glib::RefPtr<Gdk::Pixbuf> getThumbnail(const LibFile::Ptr & f, int w, int h, con
 
 }
 
-void ThumbnailCache::execute(const  ThumbnailTask::Ptr & task)
+void ThumbnailCache::execute(const ptr_t & task)
 {
     int w, h;
     w = task->width();
diff --git a/src/engine/library/thumbnailcache.hpp b/src/engine/library/thumbnailcache.hpp
index 6663112..5ac6ac0 100644
--- a/src/engine/library/thumbnailcache.hpp
+++ b/src/engine/library/thumbnailcache.hpp
@@ -33,12 +33,12 @@ namespace eng {
 class ThumbnailTask
 {
 public:
-    typedef std::shared_ptr< ThumbnailTask > Ptr;
-               
+    typedef std::unique_ptr<ThumbnailTask> Ptr;
+
     ThumbnailTask(const LibFile::Ptr & f, int w, int h)
         : m_file(f), m_width(w), m_height(h)
         { }
-               
+
     const LibFile::Ptr & file()
         { return m_file; }
     int width() const
@@ -53,7 +53,7 @@ private:
 
 
 class ThumbnailCache
-    : private fwk::Worker< ThumbnailTask::Ptr >
+    : private fwk::Worker<ThumbnailTask>
 {
 public:
     ThumbnailCache(const std::string & dir,
@@ -66,7 +66,7 @@ public:
     static bool is_thumbnail_cached(const std::string & file, const std::string & thumb);
 
 protected:
-    virtual void execute(const  ThumbnailTask::Ptr & task);
+    virtual void execute(const ptr_t & task);
 private:
     std::string                                 m_cacheDir;
     std::weak_ptr<fwk::NotificationCenter> m_notif_center;
diff --git a/src/fwk/utils/mtqueue.hpp b/src/fwk/utils/mtqueue.hpp
index 1f73bc2..2a38116 100644
--- a/src/fwk/utils/mtqueue.hpp
+++ b/src/fwk/utils/mtqueue.hpp
@@ -1,7 +1,7 @@
 /*
  * niepce - fwk/utils/mtqueue.h
  *
- * Copyright (C) 2007-2008 Hubert Figuiere
+ * Copyright (C) 2007-2013 Hubert Figuiere
  *
  * 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
@@ -43,6 +43,7 @@ namespace fwk {
                virtual ~MtQueue();
 
                void add(const T &);
+               void add(T & ); // for unique_ptr<>
                T pop();
                bool empty() const;
                void clear();
@@ -74,18 +75,24 @@ namespace fwk {
                m_queue.push_back(op);
        }
 
-       
+       // for unique_ptr<>
+       template < class T > void
+       MtQueue<T>::add(T &op)
+       {
+               mutex_t::Lock lock(m_mutex);
+               m_queue.push_back(std::move(op));
+       }
+
        template < class T >
        T MtQueue<T>::pop()
        {
                T elem;
-               mutex_t::Lock lock(m_mutex);            
-               elem = m_queue.front();
+               mutex_t::Lock lock(m_mutex);
+               elem = std::move(m_queue.front());
                m_queue.pop_front();
                return elem;
        }
 
-
        template < class T >
        bool MtQueue<T>::empty() const
        {
diff --git a/src/fwk/utils/worker.hpp b/src/fwk/utils/worker.hpp
index 3cb9828..dd0196a 100644
--- a/src/fwk/utils/worker.hpp
+++ b/src/fwk/utils/worker.hpp
@@ -1,7 +1,7 @@
 /*
  * niepce - fwk/utils/worker.h
  *
- * Copyright (C) 2007-2009 Hubert Figuiere
+ * Copyright (C) 2007-2013 Hubert Figuiere
  *
  * 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
@@ -21,7 +21,7 @@
 #ifndef __FWK_UTILS_WORKER_H__
 #define __FWK_UTILS_WORKER_H__
 
-
+#include <memory>
 #include <string>
 
 #include "fwk/utils/thread.hpp"
@@ -37,20 +37,23 @@ class Worker
 public:
     Worker();
     virtual ~Worker();
-    typedef MtQueue<T> queue_t;
-    
+    typedef std::unique_ptr<T> ptr_t;
+    typedef MtQueue<ptr_t> queue_t;
+
 #ifdef BOOST_AUTO_TEST_MAIN
-    queue_t & _tasks() 
+    queue_t & _tasks()
         { return m_tasks; }
 #endif
-    void schedule(const T & );
+    /** Schedule a task. Takes ownership of it.
+     */
+    void schedule(ptr_t & ); // must be a ref so that the pointer is moved
     void clear();
 protected:
     virtual void main();
-    
+
     queue_t      m_tasks;
 private:
-    virtual void execute(const T & _op) = 0;
+    virtual void execute(const ptr_t & _op) = 0;
     Glib::Threads::Mutex m_q_mutex;
     Glib::Threads::Cond m_wait_cond;
 };
@@ -79,9 +82,9 @@ template <class T>
 void Worker<T>::main()
 {
     m_terminated = false;
-    
+
     do {
-        T op;
+        ptr_t op;
         {
             // make sure we terminate the thread before we unlock
             // the task queue.
@@ -103,7 +106,7 @@ void Worker<T>::main()
 }
 
 template <class T>
-void Worker<T>::schedule(const T & _op)
+void Worker<T>::schedule(ptr_t & _op)
 {
     Glib::Threads::Mutex::Lock lock(m_q_mutex);
     m_tasks.add(_op);
diff --git a/src/libraryclient/locallibraryserver.hpp b/src/libraryclient/locallibraryserver.hpp
index 08c4627..79bccc0 100644
--- a/src/libraryclient/locallibraryserver.hpp
+++ b/src/libraryclient/locallibraryserver.hpp
@@ -1,7 +1,7 @@
 /*
  * niepce - libraryclient/locallibraryserver.h
  *
- * Copyright (C) 2007 Hubert Figuiere
+ * Copyright (C) 2007-2013 Hubert Figuiere
  *
  * 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
@@ -15,7 +15,7 @@
  *
  * 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., 51 Franklin Street, Fifth Floor, Boston, MA  
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA
  */
 
@@ -30,13 +30,13 @@
 namespace libraryclient {
 
        class LocalLibraryServer
-               : public fwk::Worker< eng::Op::Ptr >
+               : public fwk::Worker<eng::Op>
        {
        public:
                /** create the local server for the library whose dir is specified */
-               LocalLibraryServer(const std::string & dir, 
+               LocalLibraryServer(const std::string & dir,
                                                   const fwk::NotificationCenter::Ptr & nc)
-                       : fwk::Worker< eng::Op::Ptr >()
+                       : fwk::Worker<eng::Op>()
                        , m_library(eng::Library::Ptr(new eng::Library(dir, nc)))
                        {
                        }
@@ -45,7 +45,7 @@ namespace libraryclient {
                                return m_library && m_library->ok();
                        }
        protected:
-               virtual void execute(const eng::Op::Ptr & _op);
+               virtual void execute(const ptr_t & _op);
 
        private:
                eng::Library::Ptr m_library;