From 5e3ec0e89155c2790c11bc06fb5e7e4b18cef87a Mon Sep 17 00:00:00 2001
From: Bill Somerville <g4wjs@classdesign.com>
Date: Sun, 12 Jul 2015 10:28:28 +0000
Subject: [PATCH] Move pseudo RNG seeding to start of application

Also switched  to qrand() in place  of rand() where possible  as it is
thread safe.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@5716 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
---
 Modulator.cpp       |  7 +++----
 WSPRBandHopping.cpp |  7 -------
 getfile.cpp         |  4 ++--
 main.cpp            | 13 +++++++++++++
 mainwindow.cpp      |  2 +-
 psk_reporter.cpp    |  1 -
 6 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/Modulator.cpp b/Modulator.cpp
index e6bf3da1d..d8023547d 100644
--- a/Modulator.cpp
+++ b/Modulator.cpp
@@ -32,14 +32,13 @@ Modulator::Modulator (unsigned frameRate, unsigned periodLengthInSeconds,
   , m_phi {0.0}
   , m_toneSpacing {0.0}
   , m_fSpread {0.0}
+  , m_itone0 {0}
   , m_frameRate {frameRate}
   , m_period {periodLengthInSeconds}
   , m_state {Idle}
   , m_tuning {false}
   , m_cwLevel {false}
 {
-  qsrand (QDateTime::currentMSecsSinceEpoch()); // Initialize random seed
-  m_itone0=0;
 }
 
 void Modulator::start (unsigned symbolsLength, double framesPerSymbol,
@@ -232,8 +231,8 @@ qint64 Modulator::readData (char * data, qint64 maxSize)
 
           int j=m_ic/480;
           if(m_fSpread>0.0 and j!=j0) {
-            float x1=(float)rand()/RAND_MAX;
-            float x2=(float)rand()/RAND_MAX;
+            float x1=(float)qrand()/RAND_MAX;
+            float x2=(float)qrand()/RAND_MAX;
             toneFrequency = toneFrequency0 + 0.5*m_fSpread*(x1+x2-1.0);
             m_dphi = m_twoPi * toneFrequency / m_frameRate;
             j0=j;
diff --git a/WSPRBandHopping.cpp b/WSPRBandHopping.cpp
index ce1e1d568..1638f5368 100644
--- a/WSPRBandHopping.cpp
+++ b/WSPRBandHopping.cpp
@@ -6,7 +6,6 @@
 #include <QList>
 #include <QSet>
 #include <QtWidgets>
-#include <sys/time.h>
 
 #include "SettingsGroup.hpp"
 #include "Configuration.hpp"
@@ -119,12 +118,6 @@ Dialog::Dialog (QSettings * settings, Configuration const * configuration, BandL
   main_layout->addLayout (bottom_layout);
 
   setLayout (main_layout);
-    
-  //init random seed for random number generator used in tx scheduler
-  struct timeval time;
-  gettimeofday(&time,NULL);
-  srand((time.tv_sec*1000)+(time.tv_usec/1000));
-    
 }
 
 Dialog::~Dialog ()
diff --git a/getfile.cpp b/getfile.cpp
index baa41801d..2dd55443d 100644
--- a/getfile.cpp
+++ b/getfile.cpp
@@ -145,8 +145,8 @@ float gran()
    * that are inside the unit circle
    */
   do {
-    v1 = 2.0 * (float)rand() / RAND_MAX - 1;
-    v2 = 2.0 * (float)rand() / RAND_MAX - 1;
+    v1 = 2.0 * (float)qrand() / RAND_MAX - 1;
+    v2 = 2.0 * (float)qrand() / RAND_MAX - 1;
     rsq = v1*v1 + v2*v2;
   } while(rsq >= 1.0 || rsq == 0.0);
   fac = sqrt(-2.0*log(rsq)/rsq);
diff --git a/main.cpp b/main.cpp
index a2bf312db..5ed5b2aa6 100644
--- a/main.cpp
+++ b/main.cpp
@@ -5,6 +5,7 @@
 
 #include <locale.h>
 
+#include <QDateTime>
 #include <QApplication>
 #include <QRegularExpression>
 #include <QObject>
@@ -28,6 +29,18 @@
 #include "TraceFile.hpp"
 #include "mainwindow.h"
 
+namespace
+{
+  struct RNGSetup
+  {
+    RNGSetup ()
+    {
+      // one time seed of pseudo RNGs from current time
+      auto seed = QDateTime::currentMSecsSinceEpoch ();
+      qsrand (seed);            // this is good for rand() as well
+    }
+  } seeding;
+}
 
 int main(int argc, char *argv[])
 {
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 88d5b720b..d275c8e0b 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -4009,7 +4009,7 @@ void MainWindow::p1ReadFromStdout()                        //p1readFromStdout
       m_nWSPRdecodes=0;
       ui->DecodeButton->setChecked (false);
       if(m_uploadSpots) {
-        float x=rand()/((double)RAND_MAX + 1.0);
+        float x=qrand()/((double)RAND_MAX + 1.0);
         int msdelay=20000*x;
         uploadTimer->start(msdelay);                         //Upload delay
       } else {
diff --git a/psk_reporter.cpp b/psk_reporter.cpp
index dd2b424ea..82db043a6 100644
--- a/psk_reporter.cpp
+++ b/psk_reporter.cpp
@@ -38,7 +38,6 @@ PSK_Reporter::PSK_Reporter(MessageClient * message_client, QObject *parent) :
                            "00960004";        // Report time
 
 
-    qsrand(QDateTime::currentDateTime().toTime_t());
     m_randomId_h = QString("%1").arg(qrand(),8,16,QChar('0'));
 
     QHostInfo::lookupHost("report.pskreporter.info", this, SLOT(dnsLookupResult(QHostInfo)));