[Bluetooth] Optimize loops

Decrease complexity from O(N+N*logN) to just O(N) for cases like

foreach (Key key, map.keys())
    Value value = map.value(key);

, by rewriting with use of iterators.

Change-Id: I81f1334797f16b624293fcebdee885b2be3c89f1
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp b/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
index 7f477a02..b0fd88d5 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
@@ -239,9 +239,14 @@ void QBluetoothDeviceDiscoveryAgentPrivate::startBluez5()
     QDBusPendingReply<ManagedObjectList> reply = managerBluez5->GetManagedObjects();
     reply.waitForFinished();
     if (!reply.isError()) {
-        foreach (const QDBusObjectPath &path, reply.value().keys()) {
-            const InterfaceList ifaceList = reply.value().value(path);
-            foreach (const QString &iface, ifaceList.keys()) {
+        ManagedObjectList managedObjectList = reply.value();
+        for (ManagedObjectList::const_iterator it = managedObjectList.constBegin(); it != managedObjectList.constEnd(); ++it) {
+            const QDBusObjectPath &path = it.key();
+            const InterfaceList &ifaceList = it.value();
+
+            for (InterfaceList::const_iterator jt = ifaceList.constBegin(); jt != ifaceList.constEnd(); ++jt) {
+                const QString &iface = jt.key();
+
                 if (iface == QStringLiteral("org.bluez.Device1")) {
 
                     if (path.path().indexOf(adapterBluez5->path()) != 0)