Make QBuffer::bytesAvailable() work

We don't need to keep an internal QBuffer position, we can just use the
one from QIODevice::pos(). It will keep track of goings ahead and
backwards for us, plus it will make the default bytesAvailable() work
out-of-the-box too.

This error was reported on IRC.

Change-Id: I8559e8ee56edaa01ca8732c1f1012082ebe3a3f2
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

1 files changed, 4 insertions, 15 deletions

diff --git a/src/corelib/io/qbuffer.cpp b/src/corelib/io/qbuffer.cpp
index 5975e01e76..4b7edd8481 100644
--- a/src/corelib/io/qbuffer.cpp
+++ b/src/corelib/io/qbuffer.cpp
@@ -61,7 +61,6 @@ public:
 
     QByteArray *buf;
     QByteArray defaultBuf;
-    int ioIndex;
 
     virtual qint64 peek(char *data, qint64 maxSize);
     virtual QByteArray peek(qint64 maxSize);
@@ -157,14 +156,12 @@ QBuffer::QBuffer()
 {
     Q_D(QBuffer);
     d->buf = &d->defaultBuf;
-    d->ioIndex = 0;
 }
 QBuffer::QBuffer(QByteArray *buf)
     : QIODevice(*new QBufferPrivate)
 {
     Q_D(QBuffer);
     d->buf = buf ? buf : &d->defaultBuf;
-    d->ioIndex = 0;
     d->defaultBuf.clear();
 }
 #else
@@ -180,7 +177,6 @@ QBuffer::QBuffer(QObject *parent)
 {
     Q_D(QBuffer);
     d->buf = &d->defaultBuf;
-    d->ioIndex = 0;
 }
 
 /*!
@@ -206,7 +202,6 @@ QBuffer::QBuffer(QByteArray *byteArray, QObject *parent)
     Q_D(QBuffer);
     d->buf = byteArray ? byteArray : &d->defaultBuf;
     d->defaultBuf.clear();
-    d->ioIndex = 0;
 }
 #endif
 
@@ -253,7 +248,6 @@ void QBuffer::setBuffer(QByteArray *byteArray)
         d->buf = &d->defaultBuf;
     }
     d->defaultBuf.clear();
-    d->ioIndex = 0;
 }
 
 /*!
@@ -312,7 +306,6 @@ void QBuffer::setData(const QByteArray &data)
         return;
     }
     *d->buf = data;
-    d->ioIndex = 0;
 }
 
 /*!
@@ -340,7 +333,6 @@ bool QBuffer::open(OpenMode flags)
 
     if ((flags & Truncate) == Truncate)
         d->buf->resize(0);
-    d->ioIndex = (flags & Append) == Append ? d->buf->size() : 0;
 
     return QIODevice::open(flags);
 }
@@ -390,7 +382,6 @@ bool QBuffer::seek(qint64 pos)
         qWarning("QBuffer::seek: Invalid pos: %d", int(pos));
         return false;
     }
-    d->ioIndex = int(pos);
     return QIODevice::seek(pos);
 }
 
@@ -420,10 +411,9 @@ bool QBuffer::canReadLine() const
 qint64 QBuffer::readData(char *data, qint64 len)
 {
     Q_D(QBuffer);
-    if ((len = qMin(len, qint64(d->buf->size()) - d->ioIndex)) <= 0)
+    if ((len = qMin(len, qint64(d->buf->size()) - pos())) <= 0)
         return qint64(0);
-    memcpy(data, d->buf->constData() + d->ioIndex, len);
-    d->ioIndex += int(len);
+    memcpy(data, d->buf->constData() + pos(), len);
     return len;
 }
 
@@ -433,7 +423,7 @@ qint64 QBuffer::readData(char *data, qint64 len)
 qint64 QBuffer::writeData(const char *data, qint64 len)
 {
     Q_D(QBuffer);
-    int extraBytes = d->ioIndex + len - d->buf->size();
+    int extraBytes = pos() + len - d->buf->size();
     if (extraBytes > 0) { // overflow
         int newSize = d->buf->size() + extraBytes;
         d->buf->resize(newSize);
@@ -443,8 +433,7 @@ qint64 QBuffer::writeData(const char *data, qint64 len)
         }
     }
 
-    memcpy(d->buf->data() + d->ioIndex, (uchar *)data, int(len));
-    d->ioIndex += int(len);
+    memcpy(d->buf->data() + pos(), (uchar *)data, int(len));
 
 #ifndef QT_NO_QOBJECT
     d->writtenSinceLastEmit += len;