QWinOverlappedIoNotifier: multiple I/O operations on the same handle

When doing multiple I/O operations on the same handle, we get notified
for every operations. These must be distinguished by comparing the
pointer to the OVERLAPPED struct.

We now pass the OVERLAPPED pointer via the notified signal and let the
receiver decide if it wants to handle this notification.

Change-Id: I4efe70f39c6ae5282b949f2f4b21f6e7dd3df785
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/src/corelib/io/qwindowspipereader.cpp b/src/corelib/io/qwindowspipereader.cpp
index ea29e483bb..8a06a7ba21 100644
--- a/src/corelib/io/qwindowspipereader.cpp
+++ b/src/corelib/io/qwindowspipereader.cpp
@@ -68,7 +68,7 @@ QWindowsPipeReader::~QWindowsPipeReader()
 {
     if (readSequenceStarted) {
         CancelIo(handle);
-        dataReadNotifier->waitForNotified(-1);
+        dataReadNotifier->waitForNotified(-1, &overlapped);
     }
 }
 
@@ -156,8 +156,10 @@ bool QWindowsPipeReader::canReadLine() const
     \internal
     Will be called whenever the read operation completes.
  */
-void QWindowsPipeReader::notified(DWORD numberOfBytesRead, DWORD errorCode)
+void QWindowsPipeReader::notified(DWORD numberOfBytesRead, DWORD errorCode, OVERLAPPED *notifiedOverlapped)
 {
+    if (&overlapped != notifiedOverlapped)
+        return;
     if (!completeAsyncRead(numberOfBytesRead, errorCode)) {
         pipeBroken = true;
         emit pipeClosed();
@@ -281,7 +283,7 @@ bool QWindowsPipeReader::waitForReadyRead(int msecs)
     if (!readSequenceStarted)
         return false;
     readyReadEmitted = false;
-    dataReadNotifier->waitForNotified(msecs);
+    dataReadNotifier->waitForNotified(msecs, &overlapped);
     return readyReadEmitted;
 }