qxt-mini: multiple Linux support fixes

- Register an event filter once and keep it there. The refcount goes out
of whack. Will further investigate.
- Use an iterator over all shortcuts registered for given key
combination
- Lessen logspam

Keyboard shortcut support on Linux looks pretty good now.

The issue that blocked keys from being further processed was running
XGrabKey multiple times with various modifiers. XGrabKey will block
unlisted modifiers from being passed to other apps. The solution was to
register once with AnyModifier and care about modifiers only later.

1 files changed, 47 insertions, 23 deletions

diff --git a/qxt-mini/qxtglobalshortcut.cpp b/qxt-mini/qxtglobalshortcut.cpp
index bf3ed33d..298472b5 100644
--- a/qxt-mini/qxtglobalshortcut.cpp
+++ b/qxt-mini/qxtglobalshortcut.cpp
@@ -30,36 +30,50 @@
 *****************************************************************************/
 
 #include "qxtglobalshortcut_p.h"
+
+#include "compat/util.hpp"
+
 #include <QAbstractEventDispatcher>
-#include <QtDebug>
 #include <QApplication>
+#include <QtDebug>
+#include <QtGlobal>
 
-#ifndef Q_OS_MAC
-int QxtGlobalShortcutPrivate::ref = 0;
-#endif // Q_OS_MAC
 QHash<QPair<quint32, quint32>, QxtGlobalShortcut*> QxtGlobalShortcutPrivate::shortcuts;
 
-QxtGlobalShortcutPrivate::QxtGlobalShortcutPrivate() : enabled(true), key(Qt::Key(0)), mods(Qt::NoModifier)
+struct QxtGlobalShortcutPrivate::event_filter_installer
+{
+    static void ensure_event_filter();
+};
+
+void QxtGlobalShortcutPrivate::event_filter_installer::ensure_event_filter()
 {
 #ifndef Q_OS_MAC
-    if (ref == 0) {
-        QAbstractEventDispatcher::instance()->installNativeEventFilter(this);
+    QAbstractEventDispatcher* instance = QAbstractEventDispatcher::instance();
+    if (instance)
+    {
+        static QxtGlobalShortcutPrivate filter(QxtGlobalShortcutPrivate::tag {});
+        static bool installed =
+            (instance->installNativeEventFilter(&filter),
+             true);
+        Q_UNUSED(installed);
     }
-    ++ref;
-#endif // Q_OS_MAC
+#endif
+}
+
+QxtGlobalShortcutPrivate::QxtGlobalShortcutPrivate(QxtGlobalShortcutPrivate::tag) :
+    enabled(false), key(Qt::Key(0)), mods(Qt::NoModifier)
+{
+    qDebug() << "qxt-mini: adding event filter";
+}
+
+QxtGlobalShortcutPrivate::QxtGlobalShortcutPrivate() :
+    enabled(true), key(Qt::Key(0)), mods(Qt::NoModifier)
+{
+    QxtGlobalShortcutPrivate::event_filter_installer::ensure_event_filter();
 }
 
 QxtGlobalShortcutPrivate::~QxtGlobalShortcutPrivate()
 {
-#ifndef Q_OS_MAC
-    --ref;
-    if (ref == 0) {
-        QAbstractEventDispatcher *ed = QAbstractEventDispatcher::instance(qApp->thread());
-        if (ed != 0) {
-            ed->removeNativeEventFilter(this);
-        }
-    }
-#endif // Q_OS_MAC
     unsetShortcut();
 }
 
@@ -76,11 +90,13 @@ bool QxtGlobalShortcutPrivate::setShortcut(const QKeySequence& shortcut)
     const quint32 nativeMods = nativeModifiers(mods);
     const bool res = registerShortcut(nativeKey, nativeMods);
     if (res)
+    {
 #ifndef Q_OS_MAC
         shortcuts.insertMulti(qMakePair(nativeKey, nativeMods), &qxt_p());
 #else
         shortcuts.insert(qMakePair(nativeKey, nativeMods), &qxt_p());
 #endif
+    }
     else
         qWarning() << "QxtGlobalShortcut failed to register:" << QKeySequence(key + mods).toString();
     return res;
@@ -102,10 +118,14 @@ bool QxtGlobalShortcutPrivate::unsetShortcut()
     else
         qWarning() << "QxtGlobalShortcut failed to unregister:" << QKeySequence(key + mods).toString();
 #else
-    auto list = shortcuts.values(qMakePair(nativeKey, nativeMods));
+    using IT = decltype(shortcuts.end());
+    const auto pair = qMakePair(nativeKey, nativeMods);
+    IT it = shortcuts.find(pair);
     bool found = false;
-    for (auto it = list.begin(); it != list.end(); it++)
+    for (; it != shortcuts.end(); it++)
     {
+        if (it.key() != pair) // DO NOT REMOVE
+            break;
         if (*it == &qxt_p())
         {
             found = true;
@@ -126,13 +146,17 @@ bool QxtGlobalShortcutPrivate::unsetShortcut()
 void QxtGlobalShortcutPrivate::activateShortcut(quint32 nativeKey, quint32 nativeMods)
 {
 #ifndef Q_OS_MAC
-    auto list = shortcuts.values(qMakePair(nativeKey, nativeMods));
+    using IT = decltype(shortcuts.end());
+    const auto pair = qMakePair(nativeKey, nativeMods);
+    IT it = shortcuts.find(pair);
 
-    for (auto it = list.begin(); it != list.end(); it++)
+    for (; it != shortcuts.end(); it++)
     {
+        if (it.key() != pair) // DO NOT REMOVE
+            break;
         auto ptr = *it;
         if (ptr->isEnabled())
-            ptr->activated();
+            emit ptr->activated();
     }
 #else
     QxtGlobalShortcut* shortcut = shortcuts.value(qMakePair(nativeKey, nativeMods));