eglfs: rework hooks design

There are two problems with the current design:
1. if (hooks) hooks->foo() doesn't work in debug mode when no platform hook
   is defined. The problem doesn't arise in release mode because the compiler
   optimizes away the if (hooks) into a no-op since hooks is NULL when no
   platform hook is defined.
2. Adding a new hook requires changing every platform's hook implementation.

New approach:
1. Define QEglFSHooks as a class with virtual functions. A stub file provides
   the default implementation.
2. Platform hooks derive from above class and reimplement whatever is needed.

The filenames and variables have been changed to be more in line with the
Qt style.

Change-Id: I2eaaa5ad7c8b48a06361c4747d4f210c428c983f
Reviewed-by: Samuel Rødal <samuel.rodal@nokia.com>

10 files changed, 164 insertions, 59 deletions

diff --git a/mkspecs/devices/linux-arm-amlogic-8726M-g++/qeglfs_hooks_8726m.cpp b/mkspecs/devices/linux-arm-amlogic-8726M-g++/qeglfshooks_8726m.cpp
index 40fb2a336b..6655c50573 100644
--- a/mkspecs/devices/linux-arm-amlogic-8726M-g++/qeglfs_hooks_8726m.cpp
+++ b/mkspecs/devices/linux-arm-amlogic-8726M-g++/qeglfshooks_8726m.cpp
@@ -39,7 +39,7 @@
 **
 ****************************************************************************/
 
-#include "qeglfs_hooks.h"
+#include "qeglfshooks.h"
 #include <EGL/fbdev_window.h>
 #include <stdio.h>
 #include <sys/ioctl.h>
@@ -48,20 +48,15 @@
 #include <fcntl.h>
 #include <linux/fb.h>
 
-void QEglFSHooks::platformInit()
+class QEglFS8726MHooks : public QEglFSHooks
 {
-}
+public:
+    virtual QSize screenSize() const;
+    virtual EGLNativeWindowType createNativeWindow(const QSize &size);
+    virtual void destroyNativeWindow(EGLNativeWindowType window);
+};
 
-void QEglFSHooks::platformDestroy()
-{
-}
-
-EGLNativeDisplayType QEglFSHooks::platformDisplay() const
-{
-    return EGL_DEFAULT_DISPLAY;
-}
-
-QSize QEglFSHooks::screenSize() const
+QSize QEglFS8726MHooks::screenSize() const
 {
     int fd = open("/dev/fb0", O_RDONLY);
     if (fd == -1) {
@@ -78,7 +73,7 @@ QSize QEglFSHooks::screenSize() const
     return QSize(vinfo.xres, vinfo.yres);
 }
 
-EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
+EGLNativeWindowType QEglFS8726MHooks::createNativeWindow(const QSize &size)
 {
     fbdev_window *window = new fbdev_window;
     window->width = size.width();
@@ -87,14 +82,11 @@ EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
     return window;
 }
 
-void QEglFSHooks::destroyNativeWindow(EGLNativeWindowType window)
+void QEglFS8726MHooks::destroyNativeWindow(EGLNativeWindowType window)
 {
     delete window;
 }
 
-bool QEglFSHooks::hasCapability(QPlatformIntegration::Capability cap) const
-{
-    return false;
-}
+QEglFS8726MHooks eglFS8726MHooks;
+QEglFSHooks *platformHooks = &eglFS8726MHooks;
 
-QEglFSHooks platform_hooks;
diff --git a/mkspecs/devices/linux-arm-amlogic-8726M-g++/qmake.conf b/mkspecs/devices/linux-arm-amlogic-8726M-g++/qmake.conf
index b0b02f32e6..7525397a65 100644
--- a/mkspecs/devices/linux-arm-amlogic-8726M-g++/qmake.conf
+++ b/mkspecs/devices/linux-arm-amlogic-8726M-g++/qmake.conf
@@ -31,6 +31,6 @@ QMAKE_CXXFLAGS_RELEASE  += $$QMAKE_CFLAGS_RELEASE
 
 deviceSanityCheckCompiler()
 
-EGLFS_PLATFORM_HOOKS_SOURCES = $$PWD/qeglfs_hooks_8726m.cpp
+EGLFS_PLATFORM_HOOKS_SOURCES = $$PWD/qeglfshooks_8726m.cpp
 
 load(qt_config)
diff --git a/mkspecs/devices/linux-rasp-pi-g++/qeglfs_hooks.cpp b/mkspecs/devices/linux-rasp-pi-g++/qeglfshooks_pi.cpp
index f17af55947..21052a5b63 100644
--- a/mkspecs/devices/linux-rasp-pi-g++/qeglfs_hooks.cpp
+++ b/mkspecs/devices/linux-rasp-pi-g++/qeglfshooks_pi.cpp
@@ -39,7 +39,7 @@
 **
 ****************************************************************************/
 
-#include "qeglfs_hooks.h"
+#include "qeglfshooks.h"
 
 #include <bcm_host.h>
 
@@ -55,23 +55,35 @@
 static DISPMANX_DISPLAY_HANDLE_T dispman_display = 0;
 static DISPMANX_UPDATE_HANDLE_T dispman_update = 0;
 
-void QEglFSHooks::platformInit()
+class QEglFSPiHooks : public QEglFSHooks
+{
+public:
+    virtual void platformInit();
+    virtual void platformDestroy();
+    virtual EGLNativeDisplayType platformDisplay() const;
+    virtual QSize screenSize() const;
+    virtual EGLNativeWindowType createNativeWindow(const QSize &size);
+    virtual void destroyNativeWindow(EGLNativeWindowType window);
+    virtual bool hasCapability(QPlatformIntegration::Capability cap) const;
+};
+
+void QEglFSPiHooks::platformInit()
 {
     bcm_host_init();
 }
 
-EGLNativeDisplayType QEglFSHooks::platformDisplay() const
+EGLNativeDisplayType QEglFSPiHooks::platformDisplay() const
 {
     dispman_display = vc_dispmanx_display_open(0/* LCD */);
     return EGL_DEFAULT_DISPLAY;
 }
 
-void QEglFSHooks::platformDestroy()
+void QEglFSPiHooks::platformDestroy()
 {
     vc_dispmanx_display_close(dispman_display);
 }
 
-QSize QEglFSHooks::screenSize() const
+QSize QEglFSPiHooks::screenSize() const
 {
     //both mechanisms work
 #if 1
@@ -98,7 +110,7 @@ QSize QEglFSHooks::screenSize() const
 #endif
 }
 
-EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
+EGLNativeWindowType QEglFSPiHooks::createNativeWindow(const QSize &size)
 {
     VC_RECT_T dst_rect;
     dst_rect.x = 0;
@@ -133,14 +145,14 @@ EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
     return eglWindow;
 }
 
-void QEglFSHooks::destroyNativeWindow(EGLNativeWindowType window)
+void QEglFSPiHooks::destroyNativeWindow(EGLNativeWindowType window)
 {
     EGL_DISPMANX_WINDOW_T *eglWindow = static_cast<EGL_DISPMANX_WINDOW_T *>(window);
     vc_dispmanx_element_remove(dispman_update, eglWindow->element);
     delete eglWindow;
 }
 
-bool QEglFSHooks::hasCapability(QPlatformIntegration::Capability cap) const
+bool QEglFSPiHooks::hasCapability(QPlatformIntegration::Capability cap) const
 {
     switch (cap) {
         case QPlatformIntegration::ThreadedPixmaps:
@@ -153,4 +165,5 @@ bool QEglFSHooks::hasCapability(QPlatformIntegration::Capability cap) const
     }
 }
 
-QEglFSHooks platform_hooks;
+QEglFSPiHooks eglFSPiHooks;
+QEglFSHooks *platformHooks = &eglFSPiHooks;
diff --git a/mkspecs/devices/linux-rasp-pi-g++/qmake.conf b/mkspecs/devices/linux-rasp-pi-g++/qmake.conf
index 326d6b3b61..4c75e0b0b2 100644
--- a/mkspecs/devices/linux-rasp-pi-g++/qmake.conf
+++ b/mkspecs/devices/linux-rasp-pi-g++/qmake.conf
@@ -48,7 +48,7 @@ QMAKE_CFLAGS_RELEASE    += \
 
 QMAKE_CXXFLAGS_RELEASE = $$QMAKE_CFLAGS_RELEASE
 
-EGLFS_PLATFORM_HOOKS_SOURCES = $$PWD/qeglfs_hooks.cpp
+EGLFS_PLATFORM_HOOKS_SOURCES = $$PWD/qeglfshooks_pi.cpp
 
 # Sanity check
 deviceSanityCheckCompiler()
diff --git a/src/plugins/platforms/eglfs/eglfs.pro b/src/plugins/platforms/eglfs/eglfs.pro
index 9a36cacd05..421bbd5561 100644
--- a/src/plugins/platforms/eglfs/eglfs.pro
+++ b/src/plugins/platforms/eglfs/eglfs.pro
@@ -13,20 +13,21 @@ DESTDIR = $$QT.gui.plugins/platforms
 DEFINES += MESA_EGL_NO_X11_HEADERS
 
 #To test the hooks on x11 (xlib), comment the above define too
-#EGLFS_PLATFORM_HOOKS_SOURCES += qeglfs_hooks_x11.cpp
+#EGLFS_PLATFORM_HOOKS_SOURCES += qeglfshooks_x11.cpp
 #LIBS += -lX11
 
 SOURCES =   main.cpp \
             qeglfsintegration.cpp \
             qeglfswindow.cpp \
             qeglfsbackingstore.cpp \
-            qeglfsscreen.cpp
+            qeglfsscreen.cpp \
+            qeglfshooks_stub.cpp
 
 HEADERS =   qeglfsintegration.h \
             qeglfswindow.h \
             qeglfsbackingstore.h \
             qeglfsscreen.h \
-            qeglfs_hooks.h
+            qeglfshooks.h
 
 QMAKE_LFLAGS += $$QMAKE_LFLAGS_NOUNDEF
 
diff --git a/src/plugins/platforms/eglfs/qeglfs_hooks.h b/src/plugins/platforms/eglfs/qeglfshooks.h
index 628ef1f33b..a56c80261b 100644
--- a/src/plugins/platforms/eglfs/qeglfs_hooks.h
+++ b/src/plugins/platforms/eglfs/qeglfshooks.h
@@ -39,31 +39,34 @@
 **
 ****************************************************************************/
 
-#ifndef QEGLFS_HOOKS_H
-#define QEGLFS_HOOKS_H
+#ifndef QEGLFSHOOKS_H
+#define QEGLFSHOOKS_H
 
 #include "qplatformintegration_qpa.h"
 #include <EGL/egl.h>
 
 QT_BEGIN_NAMESPACE
 
-struct QEglFSHooks {
-    void platformInit();
-    void platformDestroy();
-    EGLNativeDisplayType platformDisplay() const;
-    QSize screenSize() const;
-    EGLNativeWindowType createNativeWindow(const QSize &size);
-    void destroyNativeWindow(EGLNativeWindowType window);
-    bool hasCapability(QPlatformIntegration::Capability cap) const;
+class QEglFSHooks
+{
+public:
+    virtual void platformInit();
+    virtual void platformDestroy();
+    virtual EGLNativeDisplayType platformDisplay() const;
+    virtual QSize screenSize() const;
+    virtual EGLNativeWindowType createNativeWindow(const QSize &size);
+    virtual void destroyNativeWindow(EGLNativeWindowType window);
+    virtual bool hasCapability(QPlatformIntegration::Capability cap) const;
 };
 
 #ifdef EGLFS_PLATFORM_HOOKS
-extern QEglFSHooks platform_hooks;
-static QEglFSHooks *hooks = &platform_hooks;
+extern QEglFSHooks *platformHooks;
+static QEglFSHooks *hooks = platformHooks;
 #else
-static QEglFSHooks *hooks = 0;
+extern QEglFSHooks stubHooks;
+static QEglFSHooks *hooks = &stubHooks;
 #endif
 
 QT_END_NAMESPACE
 
-#endif
+#endif // QEGLFSHOOKS_H
diff --git a/src/plugins/platforms/eglfs/qeglfshooks_stub.cpp b/src/plugins/platforms/eglfs/qeglfshooks_stub.cpp
new file mode 100644
index 0000000000..7cc3527a0c
--- /dev/null
+++ b/src/plugins/platforms/eglfs/qeglfshooks_stub.cpp
@@ -0,0 +1,81 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the qmake spec of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qeglfshooks.h"
+
+void QEglFSHooks::platformInit()
+{
+}
+
+void QEglFSHooks::platformDestroy()
+{
+}
+
+EGLNativeDisplayType QEglFSHooks::platformDisplay() const
+{
+    return EGL_DEFAULT_DISPLAY;
+}
+
+QSize QEglFSHooks::screenSize() const
+{
+    return QSize();
+}
+
+EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
+{
+    Q_UNUSED(size);
+    return 0;
+}
+
+void QEglFSHooks::destroyNativeWindow(EGLNativeWindowType window)
+{
+    Q_UNUSED(window);
+}
+
+bool QEglFSHooks::hasCapability(QPlatformIntegration::Capability cap) const
+{
+    Q_UNUSED(cap);
+    return false;
+}
+
+#ifndef EGLFS_PLATFORM_HOOKS
+QEglFSHooks stubHooks;
+#endif
diff --git a/src/plugins/platforms/eglfs/qeglfs_hooks_x11.cpp b/src/plugins/platforms/eglfs/qeglfshooks_x11.cpp
index 594614e7a0..cb788c52f2 100644
--- a/src/plugins/platforms/eglfs/qeglfs_hooks_x11.cpp
+++ b/src/plugins/platforms/eglfs/qeglfshooks_x11.cpp
@@ -39,31 +39,42 @@
 **
 ****************************************************************************/
 
-#include "qeglfs_hooks.h"
+#include "qeglfshooks.h"
 
 #include <X11/Xlib.h>
 
-QEglFSHooks platform_hooks;
+class QEglFSX11Hooks : public QEglFSHooks
+{
+public:
+    virtual void platformInit();
+    virtual void platformDestroy();
+    virtual EGLNativeDisplayType platformDisplay() const;
+    virtual QSize screenSize() const;
+    virtual EGLNativeWindowType createNativeWindow(const QSize &size);
+    virtual void destroyNativeWindow(EGLNativeWindowType window);
+    virtual bool hasCapability(QPlatformIntegration::Capability cap) const;
+};
+
 static Display *display = 0;
 
-void QEglFSHooks::platformInit()
+void QEglFSX11Hooks::platformInit()
 {
     display = XOpenDisplay(NULL);
     if (!display)
         qFatal("Could not open display");
 }
 
-void QEglFSHooks::platformDestroy()
+void QEglFSX11Hooks::platformDestroy()
 {
     XCloseDisplay(display);
 }
 
-EGLNativeDisplayType QEglFSHooks::platformDisplay() const
+EGLNativeDisplayType QEglFSX11Hooks::platformDisplay() const
 {
     return display;
 }
 
-QSize QEglFSHooks::screenSize() const
+QSize QEglFSX11Hooks::screenSize() const
 {
     QList<QByteArray> env = qgetenv("EGLFS_X11_SIZE").split('x');
     if (env.length() != 2)
@@ -71,7 +82,7 @@ QSize QEglFSHooks::screenSize() const
     return QSize(env.at(0).toInt(), env.at(1).toInt());
 }
 
-EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
+EGLNativeWindowType QEglFSX11Hooks::createNativeWindow(const QSize &size)
 {
     Window root = DefaultRootWindow(display);
     XSetWindowAttributes swa;
@@ -83,13 +94,17 @@ EGLNativeWindowType QEglFSHooks::createNativeWindow(const QSize &size)
     return win;
 }
 
-void QEglFSHooks::destroyNativeWindow(EGLNativeWindowType window)
+void QEglFSX11Hooks::destroyNativeWindow(EGLNativeWindowType window)
 {
     XDestroyWindow(display, window);
 }
 
-bool QEglFSHooks::hasCapability(QPlatformIntegration::Capability cap) const
+bool QEglFSX11Hooks::hasCapability(QPlatformIntegration::Capability cap) const
 {
+    Q_UNUSED(cap);
     return false;
 }
 
+static QEglFSX11Hooks eglFSX11Hooks;
+QEglFSHooks *platformHooks = &eglFSX11Hooks;
+
diff --git a/src/plugins/platforms/eglfs/qeglfsintegration.cpp b/src/plugins/platforms/eglfs/qeglfsintegration.cpp
index b1f5a69570..9b7d9246f9 100644
--- a/src/plugins/platforms/eglfs/qeglfsintegration.cpp
+++ b/src/plugins/platforms/eglfs/qeglfsintegration.cpp
@@ -43,7 +43,7 @@
 
 #include "qeglfswindow.h"
 #include "qeglfsbackingstore.h"
-#include "qeglfs_hooks.h"
+#include "qeglfshooks.h"
 
 #include <QtPlatformSupport/private/qgenericunixfontdatabase_p.h>
 #include <QtPlatformSupport/private/qgenericunixeventdispatcher_p.h>
diff --git a/src/plugins/platforms/eglfs/qeglfsscreen.cpp b/src/plugins/platforms/eglfs/qeglfsscreen.cpp
index 3c2f4c580d..ea939a9821 100644
--- a/src/plugins/platforms/eglfs/qeglfsscreen.cpp
+++ b/src/plugins/platforms/eglfs/qeglfsscreen.cpp
@@ -41,7 +41,7 @@
 
 #include "qeglfsscreen.h"
 #include "qeglfswindow.h"
-#include "qeglfs_hooks.h"
+#include "qeglfshooks.h"
 
 #include <QtPlatformSupport/private/qeglconvenience_p.h>
 #include <QtPlatformSupport/private/qeglplatformcontext_p.h>