QNearFieldTagType1Private: take more care over m_tlv{Writ,Read}er.

The writer wasn't initialized; Coverity grumbled (CID 22323).
Various stanzas take for granted that one or other is set; assert
there.  Various stanzas created each afresh, without considering they
might be leaking a prior one; delete first (could probably have
asserted == 0 instead).

Change-Id: I4c792fbbd611e06c28235ceafee40cc18268c60d
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/nfc/qnearfieldtagtype1.cpp b/src/nfc/qnearfieldtagtype1.cpp
index cbd1c1a6..778deda5 100644
--- a/src/nfc/qnearfieldtagtype1.cpp
+++ b/src/nfc/qnearfieldtagtype1.cpp
@@ -76,7 +76,8 @@ public:
     QNearFieldTagType1Private(QNearFieldTagType1 *q)
     :   q_ptr(q), m_readNdefMessageState(NotReadingNdefMessage),
         m_tlvReader(0),
-        m_writeNdefMessageState(NotWritingNdefMessage)
+        m_writeNdefMessageState(NotWritingNdefMessage),
+        m_tlvWriter(0)
     { }
 
     QNearFieldTagType1 *q_ptr;
@@ -164,11 +165,13 @@ void QNearFieldTagType1Private::progressToNextNdefReadMessageState()
         }
 
         m_readNdefMessageState = NdefReadReadingTlv;
+        delete m_tlvReader;
         m_tlvReader = new QTlvReader(q);
 
         // fall through
     }
     case NdefReadReadingTlv:
+        Q_ASSERT(m_tlvReader);
         while (!m_tlvReader->atEnd()) {
             if (!m_tlvReader->readNext())
                 break;
@@ -240,11 +243,13 @@ void QNearFieldTagType1Private::progressToNextNdefWriteMessageState()
         }
 
         m_writeNdefMessageState = NdefWriteReadingTlv;
+        delete m_tlvReader;
         m_tlvReader = new QTlvReader(q);
 
         // fall through
     }
     case NdefWriteReadingTlv:
+        Q_ASSERT(m_tlvReader);
         while (!m_tlvReader->atEnd()) {
             if (!m_tlvReader->readNext())
                 break;
@@ -264,6 +269,7 @@ void QNearFieldTagType1Private::progressToNextNdefWriteMessageState()
 
         // fall through
     case NdefWriteWritingTlv:
+        delete m_tlvWriter;
         m_tlvWriter = new QTlvWriter(q);
 
         // write old TLVs
@@ -282,6 +288,7 @@ void QNearFieldTagType1Private::progressToNextNdefWriteMessageState()
         // fall through
     case NdefWriteWritingTlvFlush:
         // flush the writer
+        Q_ASSERT(m_tlvWriter);
         if (m_tlvWriter->process(true)) {
             m_nextExpectedRequestId = QNearFieldTarget::RequestId();
             m_writeNdefMessageState = NotWritingNdefMessage;