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>

6 files changed, 23 insertions, 26 deletions

diff --git a/tests/auto/network/access/hpack/tst_hpack.cpp b/tests/auto/network/access/hpack/tst_hpack.cpp
index bd337c9f5f..810745a065 100644
--- a/tests/auto/network/access/hpack/tst_hpack.cpp
+++ b/tests/auto/network/access/hpack/tst_hpack.cpp
@@ -273,13 +273,13 @@ void tst_Hpack::bitstreamCompression()
     std::vector<uchar> buffer;
     BitOStream out(buffer);
     for (unsigned i = 0; i < nValues; ++i) {
-        const bool isString = std::rand() % 1000 > 500;
+        const bool isString = QRandomGenerator::global()->bounded(1000) > 500;
         isA.push_back(isString);
         if (!isString) {
-            integers.push_back(std::rand() % 1000);
+            integers.push_back(QRandomGenerator::global()->bounded(1000u));
             out.write(integers.back());
         } else {
-            const auto start = std::rand() % (bytes.length() / 2);
+            const auto start = QRandomGenerator::global()->bounded(uint(bytes.length()) / 2);
             auto end = start * 2;
             if (!end)
                 end = bytes.length() / 2;
@@ -287,7 +287,7 @@ void tst_Hpack::bitstreamCompression()
             const auto &s = strings.back();
             totalStringBytes += s.size();
             QByteArray data(s.c_str(), int(s.size()));
-            const bool compressed(std::rand() % 1000 > 500);
+            const bool compressed(QRandomGenerator::global()->bounded(1000) > 500);
             out.write(data, compressed);
         }
     }
@@ -442,8 +442,8 @@ void tst_Hpack::lookupTableDynamic()
         // Strings are repeating way too often, I want to
         // have at least some items really evicted and not found,
         // therefore these weird dances with start/len.
-        const quint32 start = std::rand() % (dataSize - 10);
-        quint32 len = std::rand() % (dataSize - start);
+        const quint32 start = QRandomGenerator::global()->bounded(dataSize - 10);
+        quint32 len = QRandomGenerator::global()->bounded(dataSize - start);
         if (!len)
             len = 1;
 
diff --git a/tests/auto/network/access/http2/tst_http2.cpp b/tests/auto/network/access/http2/tst_http2.cpp
index 7b453ca635..51e1849512 100644
--- a/tests/auto/network/access/http2/tst_http2.cpp
+++ b/tests/auto/network/access/http2/tst_http2.cpp
@@ -224,7 +224,7 @@ void tst_Http2::multipleRequests()
     };
 
     for (int i = 0; i < nRequests; ++i)
-        sendRequest(i, priorities[std::rand() % 3]);
+        sendRequest(i, priorities[QRandomGenerator::global()->bounded(3)]);
 
     runEventLoop();
 
diff --git a/tests/auto/network/access/qftp/tst_qftp.cpp b/tests/auto/network/access/qftp/tst_qftp.cpp
index fba0508f04..4bc43f068c 100644
--- a/tests/auto/network/access/qftp/tst_qftp.cpp
+++ b/tests/auto/network/access/qftp/tst_qftp.cpp
@@ -276,8 +276,7 @@ void tst_QFtp::init()
 
     inFileDirExistsFunction = false;
 
-    srand(time(0));
-    uniqueExtension = QString::number((quintptr)this) + QString::number(rand())
+    uniqueExtension = QString::number((quintptr)this) + QString::number(QRandomGenerator::global()->generate())
         + QString::number((qulonglong)time(0));
 }
 
diff --git a/tests/auto/network/access/qnetworkdiskcache/tst_qnetworkdiskcache.cpp b/tests/auto/network/access/qnetworkdiskcache/tst_qnetworkdiskcache.cpp
index e996347a9a..856033fb63 100644
--- a/tests/auto/network/access/qnetworkdiskcache/tst_qnetworkdiskcache.cpp
+++ b/tests/auto/network/access/qnetworkdiskcache/tst_qnetworkdiskcache.cpp
@@ -30,6 +30,7 @@
 #include <QtTest/QtTest>
 #include <QtNetwork/QtNetwork>
 #include <qnetworkdiskcache.h>
+#include <qrandom.h>
 
 #include <algorithm>
 
@@ -693,25 +694,25 @@ public:
 
             if (write) {
                 QNetworkCacheMetaData m;
-                if (qrand() % 2 == 0)
+                if (QRandomGenerator::global()->bounded(2) == 0)
                     m = metaData;
                 else
                     m = metaData2;
 
-                if (qrand() % 20 == 1) {
+                if (QRandomGenerator::global()->bounded(20) == 1) {
                     //qDebug() << "write update";
                     cache.updateMetaData(m);
                     continue;
                 }
 
                 QIODevice *device = cache.prepare(m);
-                if (qrand() % 20 == 1) {
+                if (QRandomGenerator::global()->bounded(20) == 1) {
                     //qDebug() << "write remove";
                     cache.remove(url);
                     continue;
                 }
                 QVERIFY(device);
-                if (qrand() % 2 == 0)
+                if (QRandomGenerator::global()->bounded(2) == 0)
                     device->write(longString);
                 else
                     device->write(longString2);
@@ -740,9 +741,9 @@ public:
                     delete d;
                 }
             }
-            if (qrand() % 5 == 1)
+            if (QRandomGenerator::global()->bounded(5) == 1)
                 cache.remove(url);
-            if (qrand() % 5 == 1)
+            if (QRandomGenerator::global()->bounded(5) == 1)
                 cache.clear();
             sleep(0);
         }
@@ -791,7 +792,6 @@ void tst_QNetworkDiskCache::sync()
     return;
 
     QTime midnight(0, 0, 0);
-    qsrand(midnight.secsTo(QTime::currentTime()));
     Runner reader(tempDir.path());
     reader.dt = QDateTime::currentDateTime();
     reader.write = false;
diff --git a/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp b/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
index 93afca3d48..b6b5f5ae70 100644
--- a/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
+++ b/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
@@ -33,6 +33,7 @@
 #include <QtCore/QUrl>
 #include <QtCore/QEventLoop>
 #include <QtCore/QFile>
+#include <QtCore/QRandomGenerator>
 #include <QtCore/QSharedPointer>
 #include <QtCore/QScopedPointer>
 #include <QtCore/QTemporaryFile>
@@ -120,12 +121,11 @@ class tst_QNetworkReply: public QObject
     static QString createUniqueExtension()
     {
         if (!seedCreated) {
-            qsrand(QTime(0,0,0).msecsTo(QTime::currentTime()) + QCoreApplication::applicationPid());
             seedCreated = true; // not thread-safe, but who cares
         }
         return QString::number(QTime(0, 0, 0).msecsTo(QTime::currentTime()))
             + QLatin1Char('-') + QString::number(QCoreApplication::applicationPid())
-            + QLatin1Char('-') + QString::number(qrand());
+            + QLatin1Char('-') + QString::number(QRandomGenerator::global()->generate());
     }
 
     static QString tempRedirectReplyStr() {
@@ -4852,7 +4852,7 @@ void tst_QNetworkReply::ioPostToHttpsUploadProgress()
     // server send the data much faster than expected.
     // So better provide random data that cannot be compressed.
     for (int i = 0; i < wantedSize; ++i)
-        sourceFile += (char)qrand();
+        sourceFile += (char)QRandomGenerator::global()->generate();
 
     // emulate a minimal https server
     SslServer server;
@@ -4932,7 +4932,7 @@ void tst_QNetworkReply::ioGetFromBuiltinHttp()
     // server send the data much faster than expected.
     // So better provide random data that cannot be compressed.
     for (int i = 0; i < wantedSize; ++i)
-        testData += (char)qrand();
+        testData += (char)QRandomGenerator::global()->generate();
 
     QByteArray httpResponse = QByteArray("HTTP/1.0 200 OK\r\nContent-Length: ");
     httpResponse += QByteArray::number(testData.size());
@@ -8748,7 +8748,7 @@ public slots:
         m_receivedData += data;
         if (!m_parsedHeaders && m_receivedData.contains("\r\n\r\n")) {
             m_parsedHeaders = true;
-            QTimer::singleShot(qrand()%60, this, SLOT(closeDelayed())); // simulate random network latency
+            QTimer::singleShot(QRandomGenerator::global()->bounded(60), this, SLOT(closeDelayed())); // simulate random network latency
             // This server simulates a web server connection closing, e.g. because of Apaches MaxKeepAliveRequests or KeepAliveTimeout
             // In this case QNAM needs to re-send the upload data but it had a bug which then corrupts the upload
             // This test catches that.
diff --git a/tests/auto/network/socket/qtcpsocket/tst_qtcpsocket.cpp b/tests/auto/network/socket/qtcpsocket/tst_qtcpsocket.cpp
index 7340817ade..d7c8c8c378 100644
--- a/tests/auto/network/socket/qtcpsocket/tst_qtcpsocket.cpp
+++ b/tests/auto/network/socket/qtcpsocket/tst_qtcpsocket.cpp
@@ -1,7 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2016 The Qt Company Ltd.
-** Copyright (C) 2016 Intel Corporation.
+** Copyright (C) 2017 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the test suite of the Qt Toolkit.
@@ -57,6 +57,7 @@
 #if QT_CONFIG(process)
 # include <QProcess>
 #endif
+#include <QRandomGenerator>
 #include <QStringList>
 #include <QTcpServer>
 #include <QTcpSocket>
@@ -305,8 +306,6 @@ public:
 tst_QTcpSocket::tst_QTcpSocket()
     : firstFailName("qt-test-server-first-fail")
 {
-    qsrand(time(NULL));
-
     tmpSocket = 0;
 
     //This code relates to the socketsConstructedBeforeEventLoop test case
@@ -581,8 +580,7 @@ void tst_QTcpSocket::bind()
                 // try to get a random port number
                 // we do this to ensure we're not trying to bind to the same port as we've just used in
                 // a previous run - race condition with the OS actually freeing the port
-                Q_STATIC_ASSERT(RAND_MAX > 1024);
-                port = qrand() & USHRT_MAX;
+                port = QRandomGenerator::global()->generate() & USHRT_MAX;
                 if (port < 1024)
                     continue;
             }