TransactionHistory: guard tx info list against concurrent access

src/libwalletqt/TransactionHistory.cpp

@@ -32,10 +32,13 @@
 
 #include <QFile>
 #include <QDebug>
+#include <QReadLocker>
+#include <QWriteLocker>
 
 
 TransactionInfo *TransactionHistory::transaction(int index)
 {
+    QReadLocker locker(&m_tinfoLock);
 
     if (index < 0 || index >= m_tinfo.size()) {
         qCritical("%s: no transaction info for index %d", __FUNCTION__, index);
@@ -53,13 +56,18 @@ TransactionInfo *TransactionHistory::transaction(int index)
 
 QList<TransactionInfo *> TransactionHistory::getAll(quint32 accountIndex) const
 {
-    // XXX this invalidates previously saved history that might be used by model
+    QDateTime firstDateTime = QDateTime(QDate(2014, 4, 18)); // the genesis block
+    QDateTime lastDateTime  = QDateTime::currentDateTime().addDays(1); // tomorrow (guard against jitter and timezones)
+
     emit refreshStarted();
+
+    {
+        QWriteLocker locker(&m_tinfoLock);
+
+        // XXX this invalidates previously saved history that might be used by model
         qDeleteAll(m_tinfo);
         m_tinfo.clear();
 
-    QDateTime firstDateTime = QDateTime(QDate(2014, 4, 18)); // the genesis block
-    QDateTime lastDateTime  = QDateTime::currentDateTime().addDays(1); // tomorrow (guard against jitter and timezones)
         quint64 lastTxHeight = 0;
         m_locked = false;
         m_minutesToUnlock = 0;
@@ -88,6 +96,8 @@ QList<TransactionInfo *> TransactionHistory::getAll(quint32 accountIndex) const
             }
 
         }
+    }
+
     emit refreshFinished();
 
     if (m_firstDateTime != firstDateTime) {
@@ -112,6 +122,8 @@ void TransactionHistory::refresh(quint32 accountIndex)
 
 quint64 TransactionHistory::count() const
 {
+    QReadLocker locker(&m_tinfoLock);
+
     return m_tinfo.count();
 }
 

src/libwalletqt/TransactionHistory.h

@@ -31,6 +31,7 @@
 
 #include <QObject>
 #include <QList>
+#include <QReadWriteLock>
 #include <QDateTime>
 
 namespace Monero {
@@ -76,6 +77,7 @@ private:
     friend class Wallet;
     Monero::TransactionHistory * m_pimpl;
     mutable QList<TransactionInfo*> m_tinfo;
+    mutable QReadWriteLock m_tinfoLock;
     mutable QDateTime   m_firstDateTime;
     mutable QDateTime   m_lastDateTime;
     mutable int m_minutesToUnlock;