From b8837b66f345ee7030c1b01a70efb115d6b1b1df Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Mon, 22 Sep 2014 09:59:58 +0200
Subject: [PATCH] ShmPool returns QWeakPointer<Buffer> instead of Buffer*

Requires effad12d8b1169d9ffe851fc3f0143eeb8deb10d in kwayland.
---
 scene_qpainter.cpp          | 32 +++++++++++++++++++-------------
 scene_qpainter.h            |  2 +-
 tests/waylandclienttest.cpp |  2 +-
 wayland_backend.cpp         |  2 +-
 4 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/scene_qpainter.cpp b/scene_qpainter.cpp
index c458e24aa5..69a2bd6c64 100644
--- a/scene_qpainter.cpp
+++ b/scene_qpainter.cpp
@@ -82,7 +82,7 @@ WaylandQPainterBackend::WaylandQPainterBackend()
     : QPainterBackend()
     , m_needsFullRepaint(true)
     , m_backBuffer(QImage(QSize(), QImage::Format_RGB32))
-    , m_buffer(NULL)
+    , m_buffer()
 {
     connect(Wayland::WaylandBackend::self()->shmPool(), SIGNAL(poolResized()), SLOT(remapBuffer()));
     connect(Wayland::WaylandBackend::self(), &Wayland::WaylandBackend::shellSurfaceSizeChanged,
@@ -94,7 +94,7 @@ WaylandQPainterBackend::WaylandQPainterBackend()
 WaylandQPainterBackend::~WaylandQPainterBackend()
 {
     if (m_buffer) {
-        m_buffer->setUsed(false);
+        m_buffer.toStrongRef()->setUsed(false);
     }
 }
 
@@ -112,7 +112,7 @@ void WaylandQPainterBackend::present(int mask, const QRegion &damage)
     Compositor::self()->aboutToSwapBuffers();
     m_needsFullRepaint = false;
     auto s = Wayland::WaylandBackend::self()->surface();
-    s->attachBuffer(m_buffer->buffer());
+    s->attachBuffer(m_buffer);
     s->damage(damage);
     s->commit();
 }
@@ -123,8 +123,8 @@ void WaylandQPainterBackend::screenGeometryChanged(const QSize &size)
     if (!m_buffer) {
         return;
     }
-    m_buffer->setUsed(false);
-    m_buffer = NULL;
+    m_buffer.toStrongRef()->setUsed(false);
+    m_buffer.clear();
 }
 
 QImage *WaylandQPainterBackend::buffer()
@@ -135,16 +135,17 @@ QImage *WaylandQPainterBackend::buffer()
 void WaylandQPainterBackend::prepareRenderingFrame()
 {
     if (m_buffer) {
-        if (m_buffer->isReleased()) {
+        auto b = m_buffer.toStrongRef();
+        if (b->isReleased()) {
             // we can re-use this buffer
-            m_buffer->setReleased(false);
+            b->setReleased(false);
             return;
         } else {
             // buffer is still in use, get a new one
-            m_buffer->setUsed(false);
+            b->setUsed(false);
         }
     }
-    m_buffer = NULL;
+    m_buffer.clear();
     const QSize size(Wayland::WaylandBackend::self()->shellSurfaceSize());
     m_buffer = Wayland::WaylandBackend::self()->shmPool()->getBuffer(size, size.width() * 4);
     if (!m_buffer) {
@@ -152,8 +153,9 @@ void WaylandQPainterBackend::prepareRenderingFrame()
         m_backBuffer = QImage();
         return;
     }
-    m_buffer->setUsed(true);
-    m_backBuffer = QImage(m_buffer->address(), size.width(), size.height(), QImage::Format_RGB32);
+    auto b = m_buffer.toStrongRef();
+    b->setUsed(true);
+    m_backBuffer = QImage(b->address(), size.width(), size.height(), QImage::Format_RGB32);
     m_backBuffer.fill(Qt::transparent);
     m_needsFullRepaint = true;
     qDebug() << "Created a new back buffer";
@@ -161,11 +163,15 @@ void WaylandQPainterBackend::prepareRenderingFrame()
 
 void WaylandQPainterBackend::remapBuffer()
 {
-    if (!m_buffer || !m_buffer->isUsed()) {
+    if (!m_buffer) {
+        return;
+    }
+    auto b = m_buffer.toStrongRef();
+    if (!b->isUsed()){
         return;
     }
     const QSize size = m_backBuffer.size();
-    m_backBuffer = QImage(m_buffer->address(), size.width(), size.height(), QImage::Format_RGB32);
+    m_backBuffer = QImage(b->address(), size.width(), size.height(), QImage::Format_RGB32);
     qDebug() << "Remapped our back buffer";
 }
 
diff --git a/scene_qpainter.h b/scene_qpainter.h
index ff7f8d579a..0871cbeadb 100644
--- a/scene_qpainter.h
+++ b/scene_qpainter.h
@@ -121,7 +121,7 @@ private Q_SLOTS:
 private:
     bool m_needsFullRepaint;
     QImage m_backBuffer;
-    KWayland::Client::Buffer *m_buffer;
+    QWeakPointer<KWayland::Client::Buffer> m_buffer;
 };
 #endif
 
diff --git a/tests/waylandclienttest.cpp b/tests/waylandclienttest.cpp
index e58662a27c..ce4ee479a5 100644
--- a/tests/waylandclienttest.cpp
+++ b/tests/waylandclienttest.cpp
@@ -211,7 +211,7 @@ void WaylandClientTest::render()
     if (!m_shm || !m_surface || !m_surface->isValid() || !m_currentSize.isValid()) {
         return;
     }
-    Buffer *buffer = m_shm->getBuffer(m_currentSize, m_currentSize.width() * 4);
+    auto buffer = m_shm->getBuffer(m_currentSize, m_currentSize.width() * 4).toStrongRef();
     buffer->setUsed(true);
     QImage image(buffer->address(), m_currentSize.width(), m_currentSize.height(), QImage::Format_ARGB32_Premultiplied);
     image.fill(s_colors[s_colorIndex]);
diff --git a/wayland_backend.cpp b/wayland_backend.cpp
index 4b0a615752..bfba07a67a 100644
--- a/wayland_backend.cpp
+++ b/wayland_backend.cpp
@@ -130,7 +130,7 @@ void X11CursorTracker::cursorChanged(uint32_t serial)
 void X11CursorTracker::installCursor(const CursorData& cursor)
 {
     const QImage &cursorImage = cursor.cursor();
-    auto buffer = m_backend->shmPool()->createBuffer(cursorImage);
+    auto buffer = m_backend->shmPool()->createBuffer(cursorImage).toStrongRef();
     if (!buffer) {
         return;
     }