Remove unused variables

* actualWriteBufferSize variable - it is a wrong old heritage related with
the implementation of a code with the analogy from the the QWindowsPipeReader
(where actualReadBufferSize is present).

* acyncWritePosition variable - it is a old heritage when the write notifier
could operate with a multiple writing operations at the same time. For this
purpose it is necessary to know the following write position in the ring buffer.
But currently all write operations happen sequentially, i.e. forbidden to carry
out startAsyncWrite() several times without completeAsyncWrite() completion.

Change-Id: I25b665b638649e6002fb194babfaa73f5ec8a6fa
Reviewed-by: Sergey Belyashov <Sergey.Belyashov@gmail.com>
Reviewed-by: Denis Shienkov <denis.shienkov@gmail.com>

2 files changed, 4 insertions, 18 deletions

diff --git a/src/serialport/qserialport_win.cpp b/src/serialport/qserialport_win.cpp
index 506dc94..f5bf080 100644
--- a/src/serialport/qserialport_win.cpp
+++ b/src/serialport/qserialport_win.cpp
@@ -101,8 +101,6 @@ QSerialPortPrivate::QSerialPortPrivate(QSerialPort *q)
     , descriptor(INVALID_HANDLE_VALUE)
     , parityErrorOccurred(false)
     , readChunkBuffer(ReadChunkSize, 0)
-    , actualWriteBufferSize(0)
-    , acyncWritePosition(0)
     , readyReadEmitted(0)
     , writeSequenceStarted(false)
     , communicationNotifier(new QWinEventNotifier(q))
@@ -229,8 +227,6 @@ void QSerialPortPrivate::close()
 
     writeSequenceStarted = false;
     writeBuffer.clear();
-    actualWriteBufferSize = 0;
-    acyncWritePosition = 0;
 
     readyReadEmitted = false;
     parityErrorOccurred = false;
@@ -311,8 +307,6 @@ bool QSerialPortPrivate::clear(QSerialPort::Directions directions)
         flags |= PURGE_RXABORT | PURGE_RXCLEAR;
     if (directions & QSerialPort::Output) {
         flags |= PURGE_TXABORT | PURGE_TXCLEAR;
-        actualWriteBufferSize = 0;
-        acyncWritePosition = 0;
         writeSequenceStarted = false;
     }
     return ::PurgeComm(descriptor, flags);
@@ -369,13 +363,10 @@ qint64 QSerialPortPrivate::systemOutputQueueSize ()
 qint64 QSerialPortPrivate::writeToBuffer(const char *data, qint64 maxSize)
 {
     char *ptr = writeBuffer.reserve(maxSize);
-    if (maxSize == 1) {
+    if (maxSize == 1)
         *ptr = *data;
-        actualWriteBufferSize++;
-    } else {
+    else
         ::memcpy(ptr, data, maxSize);
-        actualWriteBufferSize += maxSize;
-    }
 
     if (!writeSequenceStarted)
         startAsyncWrite(WriteChunkSize);
@@ -657,11 +648,10 @@ bool QSerialPortPrivate::startAsyncWrite(int maxSize)
 {
     Q_Q(QSerialPort);
 
-    qint64 nextSize = 0;
-    const char *ptr = writeBuffer.readPointerAtPosition(acyncWritePosition, nextSize);
+    qint64 nextSize = writeBuffer.nextDataBlockSize();
+    const char *ptr = writeBuffer.readPointer();
 
     nextSize = qMin(nextSize, qint64(maxSize));
-    acyncWritePosition += nextSize;
 
     // no more data to write
     if (!ptr || nextSize == 0)
@@ -763,8 +753,6 @@ void QSerialPortPrivate::completeAsyncWrite(DWORD numberOfBytes)
     Q_Q(QSerialPort);
 
     writeBuffer.free(numberOfBytes);
-    actualWriteBufferSize -= qint64(numberOfBytes);
-    acyncWritePosition -= qint64(numberOfBytes);
 
     if (numberOfBytes > 0)
         emit q->bytesWritten(numberOfBytes);
diff --git a/src/serialport/qserialport_win_p.h b/src/serialport/qserialport_win_p.h
index 059be87..5ae33ae 100644
--- a/src/serialport/qserialport_win_p.h
+++ b/src/serialport/qserialport_win_p.h
@@ -126,8 +126,6 @@ public:
 
 #ifndef Q_OS_WINCE
     QByteArray readChunkBuffer;
-    qint64 actualWriteBufferSize;
-    qint64 acyncWritePosition;
     bool readyReadEmitted;
     bool writeSequenceStarted;
     QWinEventNotifier *communicationNotifier;