qt5: fix memory leak, xcb treat bitmap cursors differently from shaped cursors

3 files changed, 142 insertions, 2 deletions

diff --git a/qt5/.md5sum b/qt5/.md5sum
index bce791b97..35360b272 100644
--- a/qt5/.md5sum
+++ b/qt5/.md5sum
@@ -1,5 +1,6 @@
 63ec6b584757eef8cd713e4958297251  qt-everywhere-opensource-src-5.7.0.tar.xz
 67165bacd3231b57d7b7db1e6bcb7d89  qt5-logo.png
+9842c327b091b360da7a4d90f5fdf4da  qtbase-memory-leak.patch
 646aea77ca90031c453a65ef61db55f9  qtbug-49452.patch
 462f079cd46f869def6858903a718bf5  qtbug-53071.patch
 da4fd787ea877516397a027412e975e1  qtbug-53071b.patch
diff --git a/qt5/Pkgfile b/qt5/Pkgfile
index 56994f2a1..97c6b8f22 100644
--- a/qt5/Pkgfile
+++ b/qt5/Pkgfile
@@ -6,13 +6,14 @@
 
 name=qt5
 version=5.7.0
-release=3
+release=4
 source=(http://download.qt.io/official_releases/qt/${version::3}/$version/single/qt-everywhere-opensource-src-$version.tar.xz
 	qt5-logo.png
 	qtbug-53071.patch
 	qtbug-53071b.patch
 	qtbug-53237.patch
-	qtbug-49452.patch)
+	qtbug-49452.patch
+	qtbase-memory-leak.patch)
 
 build() {
 	cd qt-everywhere-opensource-src-$version
@@ -27,6 +28,9 @@ build() {
 	# Fix freetype engine performance
 	patch -p1 -d qtbase -i $SRC/qtbug-49452.patch
 
+	# Fix memory leak
+	patch -p1 -d qtbase -i $SRC/qtbase-memory-leak.patch
+
 	# Respect system CXX
 	[ "$CXX" ] || CXX=g++
 	sed -i "/^QMAKE_CXX\s/s|=.*|= $CXX|" qtbase/mkspecs/common/g++-base.conf
diff --git a/qt5/qtbase-memory-leak.patch b/qt5/qtbase-memory-leak.patch
new file mode 100644
index 000000000..009b15576
--- /dev/null
+++ b/qt5/qtbase-memory-leak.patch
@@ -0,0 +1,135 @@
+From 422838685c31d9b57133a8711bfd5db92095d96d Mon Sep 17 00:00:00 2001
+From: Robin Burchell <robin.burchell@viroteck.net>
+Date: Wed, 7 Sep 2016 14:34:03 +0200
+Subject: [PATCH] xcb: Treat bitmap cursors differently from shaped cursors
+
+QXcbCursor had a "cache" of cursor handles. Unfortunately, as QXcbCursor has its
+lifetime tied to the screen, this cache grew unbounded whenever the cursor was
+set: this could be witnessed worst when repeatedly setting the current cursor to
+a different pixmap each time.
+
+We fix this by keeping the cursor cache only for the "regular" shaped cursors
+that are often shared between windows, working on the assumption that custom
+cursors are generally specific only to a given window. This makes the lifetime
+of the bitmap cursors much more clear: they are tied to that window, and when
+the window is destroyed (or changes cursor), so too is the bitmap cursor
+destroyed (if set).
+
+Reported-by: Will Thompson <wjt@endlessm.com>
+Change-Id: Ia558d858ff49e89cd5220344567203eb0267a133
+Reviewed-by: Uli Schlachter <psychon@znc.in>
+Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
+---
+ src/plugins/platforms/xcb/qxcbcursor.cpp | 24 +++++++++++++++++-------
+ src/plugins/platforms/xcb/qxcbwindow.cpp | 22 +++++++++++++++++++---
+ src/plugins/platforms/xcb/qxcbwindow.h   |  3 ++-
+ 3 files changed, 38 insertions(+), 11 deletions(-)
+
+diff --git a/src/plugins/platforms/xcb/qxcbcursor.cpp b/src/plugins/platforms/xcb/qxcbcursor.cpp
+index b321ed9..4646ced 100644
+--- a/src/plugins/platforms/xcb/qxcbcursor.cpp
++++ b/src/plugins/platforms/xcb/qxcbcursor.cpp
+@@ -353,17 +353,27 @@ void QXcbCursor::changeCursor(QCursor *cursor, QWindow *widget)
+         return;
+ 
+     xcb_cursor_t c = XCB_CURSOR_NONE;
++    bool isBitmapCursor = false;
++
+     if (cursor) {
+-        const QXcbCursorCacheKey key(*cursor);
+-        CursorHash::iterator it = m_cursorHash.find(key);
+-        if (it == m_cursorHash.end()) {
+-            const Qt::CursorShape shape = cursor->shape();
+-            it = m_cursorHash.insert(key, shape == Qt::BitmapCursor ? createBitmapCursor(cursor) : createFontCursor(shape));
++        const Qt::CursorShape shape = cursor->shape();
++        isBitmapCursor = shape == Qt::BitmapCursor;
++
++        if (!isBitmapCursor) {
++            const QXcbCursorCacheKey key(*cursor);
++            CursorHash::iterator it = m_cursorHash.find(key);
++            if (it == m_cursorHash.end()) {
++                it = m_cursorHash.insert(key, createFontCursor(shape));
++            }
++            c = it.value();
++        } else {
++            // Do not cache bitmap cursors, as otherwise they have unclear
++            // lifetime (we effectively leak xcb_cursor_t).
++            c = createBitmapCursor(cursor);
+         }
+-        c = it.value();
+     }
+ 
+-    w->setCursor(c);
++    w->setCursor(c, isBitmapCursor);
+ }
+ 
+ static int cursorIdForShape(int cshape)
+diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
+index d46228c..5f402b6 100644
+--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
++++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
+@@ -302,6 +302,7 @@ QXcbWindow::QXcbWindow(QWindow *window)
+     , m_lastWindowStateEvent(-1)
+     , m_syncState(NoSyncNeeded)
+     , m_pendingSyncRequest(0)
++    , m_currentBitmapCursor(XCB_CURSOR_NONE)
+ {
+     setConnection(xcbScreen()->connection());
+ }
+@@ -620,6 +621,9 @@ void QXcbWindow::create()
+ 
+ QXcbWindow::~QXcbWindow()
+ {
++    if (m_currentBitmapCursor != XCB_CURSOR_NONE) {
++        xcb_free_cursor(xcb_connection(), m_currentBitmapCursor);
++    }
+     if (window()->type() != Qt::ForeignWindow)
+         destroy();
+     else {
+@@ -2665,10 +2669,22 @@ bool QXcbWindow::setMouseGrabEnabled(bool grab)
+     return result;
+ }
+ 
+-void QXcbWindow::setCursor(xcb_cursor_t cursor)
++void QXcbWindow::setCursor(xcb_cursor_t cursor, bool isBitmapCursor)
+ {
+-    xcb_change_window_attributes(xcb_connection(), m_window, XCB_CW_CURSOR, &cursor);
+-    xcb_flush(xcb_connection());
++    xcb_connection_t *conn = xcb_connection();
++
++    xcb_change_window_attributes(conn, m_window, XCB_CW_CURSOR, &cursor);
++    xcb_flush(conn);
++
++    if (m_currentBitmapCursor != XCB_CURSOR_NONE) {
++        xcb_free_cursor(conn, m_currentBitmapCursor);
++    }
++
++    if (isBitmapCursor) {
++        m_currentBitmapCursor = cursor;
++    } else {
++        m_currentBitmapCursor = XCB_CURSOR_NONE;
++    }
+ }
+ 
+ void QXcbWindow::windowEvent(QEvent *event)
+diff --git a/src/plugins/platforms/xcb/qxcbwindow.h b/src/plugins/platforms/xcb/qxcbwindow.h
+index b8bcf44..f2b6904 100644
+--- a/src/plugins/platforms/xcb/qxcbwindow.h
++++ b/src/plugins/platforms/xcb/qxcbwindow.h
+@@ -97,7 +97,7 @@ class Q_XCB_EXPORT QXcbWindow : public QXcbObject, public QXcbWindowEventListene
+     bool setKeyboardGrabEnabled(bool grab) Q_DECL_OVERRIDE;
+     bool setMouseGrabEnabled(bool grab) Q_DECL_OVERRIDE;
+ 
+-    void setCursor(xcb_cursor_t cursor);
++    void setCursor(xcb_cursor_t cursor, bool isBitmapCursor);
+ 
+     QSurfaceFormat format() const Q_DECL_OVERRIDE;
+ 
+@@ -263,6 +263,7 @@ public Q_SLOTS:
+     SyncState m_syncState;
+ 
+     QXcbSyncWindowRequest *m_pendingSyncRequest;
++    xcb_cursor_t m_currentBitmapCursor;
+ };
+ 
+ QT_END_NAMESPACE