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>

4 files changed, 14 insertions, 14 deletions

diff --git a/src/corelib/animation/qabstractanimation.cpp b/src/corelib/animation/qabstractanimation.cpp
index 9d7a256191..e37f9a0271 100644
--- a/src/corelib/animation/qabstractanimation.cpp
+++ b/src/corelib/animation/qabstractanimation.cpp
@@ -152,6 +152,7 @@
 #include <QtCore/qthreadstorage.h>
 #include <QtCore/qcoreevent.h>
 #include <QtCore/qpointer.h>
+#include <QtCore/qscopedvaluerollback.h>
 
 #define DEFAULT_TIMER_INTERVAL 16
 #define PAUSE_TIMER_COARSE_THRESHOLD 2000
@@ -315,14 +316,13 @@ void QUnifiedTimer::updateAnimationTimers(qint64 currentTick)
     //* it might happen in some cases that the delta is negative because the animation driver
     //  advances faster than time.elapsed()
     if (delta > 0) {
-        insideTick = true;
+        QScopedValueRollback<bool> guard(insideTick, true);
         if (profilerCallback)
             profilerCallback(delta);
         for (currentAnimationIdx = 0; currentAnimationIdx < animationTimers.count(); ++currentAnimationIdx) {
             QAbstractAnimationTimer *animation = animationTimers.at(currentAnimationIdx);
             animation->updateAnimationsTime(delta);
         }
-        insideTick = false;
         currentAnimationIdx = 0;
     }
 }
@@ -361,10 +361,11 @@ void QUnifiedTimer::localRestart()
 
 void QUnifiedTimer::restart()
 {
-    insideRestart = true;
-    for (int i = 0; i < animationTimers.count(); ++i)
-        animationTimers.at(i)->restartAnimationTimer();
-    insideRestart = false;
+    {
+        QScopedValueRollback<bool> guard(insideRestart, true);
+        for (int i = 0; i < animationTimers.count(); ++i)
+            animationTimers.at(i)->restartAnimationTimer();
+    }
 
     localRestart();
 }
@@ -599,14 +600,13 @@ void QAnimationTimer::updateAnimationsTime(qint64 delta)
     //it might happen in some cases that the time doesn't change because events are delayed
     //when the CPU load is high
     if (delta) {
-        insideTick = true;
+        QScopedValueRollback<bool> guard(insideTick, true);
         for (currentAnimationIdx = 0; currentAnimationIdx < animations.count(); ++currentAnimationIdx) {
             QAbstractAnimation *animation = animations.at(currentAnimationIdx);
             int elapsed = QAbstractAnimationPrivate::get(animation)->totalCurrentTime
                           + (animation->direction() == QAbstractAnimation::Forward ? delta : -delta);
             animation->setCurrentTime(elapsed);
         }
-        insideTick = false;
         currentAnimationIdx = 0;
     }
 }
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;
         }
     }
 }