Change almost all other uses of qrand() to QRandomGenerator

The vast majority is actually switched to QRandomGenerator::bounded(),
which gives a mostly uniform distribution over the [0, bound)
range. There are very few floating point cases left, as many of those
that did use floating point did not need to, after all. (I did leave
some that were too ugly for me to understand)

This commit also found a couple of calls to rand() instead of qrand().

This commit does not include changes to SSL code that continues to use
qrand() (job for someone else):
  src/network/ssl/qsslkey_qt.cpp
  src/network/ssl/qsslsocket_mac.cpp
  tests/auto/network/ssl/qsslsocket/tst_qsslsocket.cpp

Change-Id: Icd0e0d4b27cb4e5eb892fffd14b5285d43f4afbf
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

5 files changed, 15 insertions, 15 deletions

diff --git a/examples/network/fortuneserver/server.cpp b/examples/network/fortuneserver/server.cpp
index 3915a73bf0..7db81fe07a 100644
--- a/examples/network/fortuneserver/server.cpp
+++ b/examples/network/fortuneserver/server.cpp
@@ -182,7 +182,7 @@ void Server::sendFortune()
     QDataStream out(&block, QIODevice::WriteOnly);
     out.setVersion(QDataStream::Qt_5_10);
 
-    out << fortunes[QRandomGenerator::bounded(fortunes.size())];
+    out << fortunes[QRandomGenerator::global()->bounded(fortunes.size())];
 //! [4] //! [7]
 
     QTcpSocket *clientConnection = tcpServer->nextPendingConnection();
diff --git a/examples/network/threadedfortuneserver/fortuneserver.cpp b/examples/network/threadedfortuneserver/fortuneserver.cpp
index 01b77e2aba..791ffc71f4 100644
--- a/examples/network/threadedfortuneserver/fortuneserver.cpp
+++ b/examples/network/threadedfortuneserver/fortuneserver.cpp
@@ -51,6 +51,8 @@
 #include "fortuneserver.h"
 #include "fortunethread.h"
 
+#include <QRandomGenerator>
+
 #include <stdlib.h>
 
 //! [0]
@@ -70,7 +72,7 @@ FortuneServer::FortuneServer(QObject *parent)
 //! [1]
 void FortuneServer::incomingConnection(qintptr socketDescriptor)
 {
-    QString fortune = fortunes.at(qrand() % fortunes.size());
+    QString fortune = fortunes.at(QRandomGenerator::global()->bounded(fortunes.size()));
     FortuneThread *thread = new FortuneThread(socketDescriptor, fortune, this);
     connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
     thread->start();
diff --git a/examples/network/threadedfortuneserver/main.cpp b/examples/network/threadedfortuneserver/main.cpp
index 3a54585fbc..fdacb28945 100644
--- a/examples/network/threadedfortuneserver/main.cpp
+++ b/examples/network/threadedfortuneserver/main.cpp
@@ -60,6 +60,5 @@ int main(int argc, char *argv[])
     QApplication app(argc, argv);
     Dialog dialog;
     dialog.show();
-    qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));
     return app.exec();
 }
diff --git a/examples/network/torrent/main.cpp b/examples/network/torrent/main.cpp
index de7516ed3f..6430d2e5f3 100644
--- a/examples/network/torrent/main.cpp
+++ b/examples/network/torrent/main.cpp
@@ -55,7 +55,6 @@
 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
-    qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));
 
     Q_INIT_RESOURCE(icons);
 
diff --git a/examples/network/torrent/torrentclient.cpp b/examples/network/torrent/torrentclient.cpp
index ba87924ff9..95232646ab 100644
--- a/examples/network/torrent/torrentclient.cpp
+++ b/examples/network/torrent/torrentclient.cpp
@@ -692,7 +692,7 @@ void TorrentClient::connectToPeers()
 
     // Start as many connections as we can
     while (!weighedPeers.isEmpty() && ConnectionManager::instance()->canAddConnection()
-           && (qrand() % (ConnectionManager::instance()->maxConnections() / 2))) {
+           && (QRandomGenerator::global()->bounded(ConnectionManager::instance()->maxConnections() / 2))) {
         PeerWireClient *client = new PeerWireClient(ConnectionManager::instance()->clientId(), this);
         RateController::instance()->addSocket(client);
         ConnectionManager::instance()->addConnection(client);
@@ -701,7 +701,7 @@ void TorrentClient::connectToPeers()
         d->connections << client;
 
         // Pick a random peer from the list of weighed peers.
-        TorrentPeer *peer = weighedPeers.takeAt(qrand() % weighedPeers.size());
+        TorrentPeer *peer = weighedPeers.takeAt(QRandomGenerator::global()->bounded(weighedPeers.size()));
         weighedPeers.removeAll(peer);
         peer->connectStart = QDateTime::currentSecsSinceEpoch();
         peer->lastVisited = peer->connectStart;
@@ -1114,7 +1114,7 @@ void TorrentClient::scheduleUploads()
         }
 
         if ((client->peerWireState() & PeerWireClient::ChokingPeer) == 0) {
-            if ((qrand() % 10) == 0)
+            if ((QRandomGenerator::global()->bounded(10)) == 0)
                 client->abort();
             else
                 client->chokePeer();
@@ -1128,7 +1128,7 @@ void TorrentClient::scheduleUploads()
     // random peer to allow it to compete for a position among the
     // downloaders.  (This is known as an "optimistic unchoke".)
     if (!allClients.isEmpty()) {
-        PeerWireClient *client = allClients[qrand() % allClients.size()];
+        PeerWireClient *client = allClients[QRandomGenerator::global()->bounded(allClients.size())];
         if (client->peerWireState() & PeerWireClient::ChokingPeer)
             client->unchokePeer();
     }
@@ -1189,7 +1189,7 @@ void TorrentClient::schedulePieceForClient(PeerWireClient *client)
         piece = d->payloads.value(client);
         if (!piece) {
             QList<TorrentPiece *> values = d->pendingPieces.values();
-            piece = values.value(qrand() % values.size());
+            piece = values.value(QRandomGenerator::global()->bounded(values.size()));
             piece->inProgress = true;
             d->payloads.insert(client, piece);
         }
@@ -1246,14 +1246,14 @@ void TorrentClient::schedulePieceForClient(PeerWireClient *client)
             ++it;
         }
         if (!partialPieces.isEmpty())
-            piece = partialPieces.value(qrand() % partialPieces.size());
+            piece = partialPieces.value(QRandomGenerator::global()->bounded(partialPieces.size()));
 
         if (!piece) {
             // Pick a random piece 3 out of 4 times; otherwise, pick either
             // one of the most common or the least common pieces available,
             // depending on the state we're in.
             int pieceIndex = 0;
-            if (d->state == WarmingUp || (qrand() & 4) == 0) {
+            if (d->state == WarmingUp || (QRandomGenerator::global()->generate() & 4) == 0) {
                 int *occurrences = new int[d->pieceCount];
                 memset(occurrences, 0, d->pieceCount * sizeof(int));
 
@@ -1293,7 +1293,7 @@ void TorrentClient::schedulePieceForClient(PeerWireClient *client)
                 }
 
                 // Select one piece randomly
-                pieceIndex = piecesReadyForDownload.at(qrand() % piecesReadyForDownload.size());
+                pieceIndex = piecesReadyForDownload.at(QRandomGenerator::global()->bounded(piecesReadyForDownload.size()));
                 delete [] occurrences;
             } else {
                 // Make up a list of available piece indices, and pick
@@ -1304,7 +1304,7 @@ void TorrentClient::schedulePieceForClient(PeerWireClient *client)
                     if (incompletePiecesAvailableToClient.testBit(i))
                         values << i;
                 }
-                pieceIndex = values.at(qrand() % values.size());
+                pieceIndex = values.at(QRandomGenerator::global()->bounded(values.size()));
             }
 
             // Create a new TorrentPiece and fill in all initial
@@ -1396,8 +1396,8 @@ int TorrentClient::requestBlocks(PeerWireClient *client, TorrentPiece *piece, in
         // speedup comes from an increased chance of receiving
         // different blocks from the different peers.
         for (int i = 0; i < bits.size(); ++i) {
-            int a = qrand() % bits.size();
-            int b = qrand() % bits.size();
+            int a = QRandomGenerator::global()->bounded(bits.size());
+            int b = QRandomGenerator::global()->bounded(bits.size());
             int tmp = bits[a];
             bits[a] = bits[b];
             bits[b] = tmp;