Use QScopedValueRollback more as a reentrancy guard

It is documented for the use, but we were rarely using it.

Change-Id: I812b9e6c8fbf204aba43ce2b79eca308ca75de88
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

3 files changed, 6 insertions, 6 deletions

diff --git a/src/corelib/io/qprocess.cpp b/src/corelib/io/qprocess.cpp
index d5d67d86f3..c7635cc7b4 100644
--- a/src/corelib/io/qprocess.cpp
+++ b/src/corelib/io/qprocess.cpp
@@ -42,6 +42,7 @@
 
 #include <qdebug.h>
 #include <qdir.h>
+#include <qscopedvaluerollback.h>
 #if defined(Q_OS_WIN)
 #include <qtimer.h>
 #endif
@@ -1062,9 +1063,8 @@ bool QProcessPrivate::tryReadFromChannel(Channel *channel)
     if (currentReadChannel == channelIdx) {
         didRead = true;
         if (!emittedReadyRead) {
-            emittedReadyRead = true;
+            QScopedValueRollback<bool> guard(emittedReadyRead, true);
             emit q->readyRead();
-            emittedReadyRead = false;
         }
     }
     emit q->channelReadyRead(int(channelIdx));
diff --git a/src/corelib/io/qwindowspipereader.cpp b/src/corelib/io/qwindowspipereader.cpp
index 15c9f52cf3..1f03ac5d5a 100644
--- a/src/corelib/io/qwindowspipereader.cpp
+++ b/src/corelib/io/qwindowspipereader.cpp
@@ -40,6 +40,7 @@
 #include "qwindowspipereader_p.h"
 #include "qiodevice_p.h"
 #include <qelapsedtimer.h>
+#include <qscopedvaluerollback.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -301,9 +302,8 @@ void QWindowsPipeReader::emitPendingReadyRead()
 {
     if (readyReadPending) {
         readyReadPending = false;
-        inReadyRead = true;
+        QScopedValueRollback<bool> guard(inReadyRead, true);
         emit readyRead();
-        inReadyRead = false;
     }
 }
 
diff --git a/src/corelib/io/qwindowspipewriter.cpp b/src/corelib/io/qwindowspipewriter.cpp
index 92e8b6db52..32536f495b 100644
--- a/src/corelib/io/qwindowspipewriter.cpp
+++ b/src/corelib/io/qwindowspipewriter.cpp
@@ -39,6 +39,7 @@
 
 #include "qwindowspipewriter_p.h"
 #include "qiodevice_p.h"
+#include <qscopedvaluerollback.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -111,9 +112,8 @@ void QWindowsPipeWriter::emitPendingBytesWrittenValue()
 
         emit canWrite();
         if (!inBytesWritten) {
-            inBytesWritten = true;
+            QScopedValueRollback<bool> guard(inBytesWritten, true);
             emit bytesWritten(bytes);
-            inBytesWritten = false;
         }
     }
 }