Don't allocate an OCIDateTime object unless we're going to use it

The QOCIDateTime destructor carefully checks that dateTime is non-null
before tidying it away, but the constructor allocated it independently
of whether it was used, leaving it in a still-not-constructed state if
the date-time it was to represent was invalid.

Only allocate if the date-time is valid; and check against null when
an OCIDateTime is being converted back to QDateTime. Add warnings if
either allocation or construction fails. Incidentally use
static_cast<> instead of C-casting (and split a long line) in the
other place that allocates an OCIDateTime descriptor.

Pick-to: 6.2 5.15
Task-number: QTBUG-98471
Change-Id: Idd5531d9f7101878802cb9a3a016d3fd80903543
Reviewed-by: Andy Shaw <andy.shaw@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 22 insertions, 7 deletions

diff --git a/src/plugins/sqldrivers/oci/qsql_oci.cpp b/src/plugins/sqldrivers/oci/qsql_oci.cpp
index 638b01b022..b0f68c0d09 100644
--- a/src/plugins/sqldrivers/oci/qsql_oci.cpp
+++ b/src/plugins/sqldrivers/oci/qsql_oci.cpp
@@ -168,16 +168,27 @@ public:
 QOCIDateTime::QOCIDateTime(OCIEnv *env, OCIError *err, const QDateTime &dt)
     : dateTime(nullptr)
 {
-    OCIDescriptorAlloc(env, reinterpret_cast<void**>(&dateTime), OCI_DTYPE_TIMESTAMP_TZ, 0, 0);
-    if (dt.isValid()) {
+    if (!dt.isValid()) {
+        // nothing to do, leave dateTime null
+    } else if (OCIDescriptorAlloc(env, reinterpret_cast<void**>(&dateTime),
+                                  OCI_DTYPE_TIMESTAMP_TZ, 0, 0) == OCI_SUCCESS) {
+        Q_ASSERT(!dt.isNull());
         const QDate date = dt.date();
+        Q_ASSERT(date.isValid());
         const QTime time = dt.time();
+        Q_ASSERT(time.isValid());
         // Zone in +hh:mm format (stripping UTC prefix from OffsetName)
-        QString timeZone = dt.timeZone().displayName(dt, QTimeZone::OffsetName).mid(3);
+        QString timeZone = dt.timeZone().displayName(dt, QTimeZone::OffsetName);
+        Q_ASSERT(timeZone.startsWith(u"UTC"));
+        timeZone = std::move(timeZone).sliced(3);
         const OraText *tz = reinterpret_cast<const OraText *>(timeZone.utf16());
-        OCIDateTimeConstruct(env, err, dateTime, date.year(), date.month(), date.day(), time.hour(),
-                             time.minute(), time.second(), time.msec() * 1000000,
-                             const_cast<OraText *>(tz), timeZone.length() * sizeof(QChar));
+        if (OCIDateTimeConstruct(env, err, dateTime, date.year(), date.month(), date.day(),
+                                 time.hour(), time.minute(), time.second(), time.msec() * 1000000,
+                                 const_cast<OraText *>(tz), timeZone.length() * sizeof(QChar))) {
+            qWarning("QOCIDateTime: Failed to construct the OCIDateTime descriptor");
+        }
+    } else {
+        qWarning("QOCIDateTime: Failed to allocate the OCIDateTime descriptor");
     }
 }
 
@@ -189,6 +200,9 @@ QOCIDateTime::~QOCIDateTime()
 
 QDateTime QOCIDateTime::fromOCIDateTime(OCIEnv *env, OCIError *err, OCIDateTime *dateTime)
 {
+    if (!dateTime)
+        return QDateTime();
+
     sb2 year;
     ub1 month, day, hour, minute, second;
     ub4 nsec;
@@ -937,7 +951,8 @@ QOCICols::QOCICols(int size, QOCIResultPrivate* dp)
 
         switch (ofi.type.id()) {
         case QMetaType::QDateTime:
-            r = OCIDescriptorAlloc(d->env, (void **)&fieldInf[idx].dataPtr, OCI_DTYPE_TIMESTAMP_TZ, 0, 0);
+            r = OCIDescriptorAlloc(d->env, static_cast<void **>(&fieldInf[idx].dataPtr),
+                                   OCI_DTYPE_TIMESTAMP_TZ, 0, 0);
             if (r != OCI_SUCCESS) {
                 qWarning("QOCICols: Unable to allocate the OCIDateTime descriptor");
                 break;