Introduce QIODevice::skipData()

QIODevice::skip() called a virtual QIODevicePrivate::skip() to
implement an efficient skipping on I/O devices for the internal
subclasses. The user subclasses cannot inherit QIODevicePrivate, so
this functionality was not externally accessible.

This patch replaces QIODevicePrivate::skip() with a virtual protected
QIODevice::skipData(). While the basic implementation simply discards
the data by reading into a dummy buffer, users can reimplement this
function to improve the performance in their subclasses.

[ChangeLog][QtCore][QIODevice] Added virtual protected skipData().
Now, subclasses can implement device-specific skipping of data.

Change-Id: I9522f7f7ab9d03ac06e972a525f8ec2fa909a617
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/corelib/io/qiodevice.h b/src/corelib/io/qiodevice.h
index 2e4debe339..e8c8dc11bf 100644
--- a/src/corelib/io/qiodevice.h
+++ b/src/corelib/io/qiodevice.h
@@ -167,6 +167,7 @@ protected:
 #endif
     virtual qint64 readData(char *data, qint64 maxlen) = 0;
     virtual qint64 readLineData(char *data, qint64 maxlen);
+    virtual qint64 skipData(qint64 maxSize);
     virtual qint64 writeData(const char *data, qint64 len) = 0;
 
     void setOpenMode(OpenMode openMode);