1 files changed, 12 insertions, 14 deletions

diff --git a/qmake/tools/qsemaphore_unix.cpp b/qmake/tools/qsemaphore_unix.cpp
index fcf28da..4516049 100644
--- a/qmake/tools/qsemaphore_unix.cpp
+++ b/qmake/tools/qsemaphore_unix.cpp
@@ -162,86 +162,84 @@ int QSemaphore::operator--(int)
     d->mutex.lock();
 
     --(d->value);
     if (d->value < 0) d->value = 0;
     ret = d->value;
 
     d->cond.wakeAll();
     d->mutex.unlock();
 
     return ret;
 }
 
 
 /*!
     Try to get access to the semaphore. If \l available() \< \a n, this
     call will block until it can get all the accesses it wants, i.e.
     until available() \>= \a n.
 */
 int QSemaphore::operator+=(int n)
 {
     int ret;
 
     d->mutex.lock();
 
+    if ( n < 0 || n > d->max ) {
+#ifdef QT_CHECK_RANGE
+        qWarning( "QSemaphore::operator+=: paramter %d out of range", n );
+#endif // QT_CHECK_RANGE
+        n = n < 0 ? 0 : d->max;
+    }
+
     while (d->value + n > d->max)
         d->cond.wait(&(d->mutex));
 
     d->value += n;
-
-#ifdef QT_CHECK_RANGE
-    if (d->value > d->max) {
-        qWarning("QSemaphore::operator+=: attempt to allocate more resources than available");
-        d->value = d->max;
-    }
-#endif
-
     ret = d->value;
 
     d->mutex.unlock();
 
     return ret;
 }
 
 
 /*!
     Release \a n accesses to the semaphore.
 */
 int QSemaphore::operator-=(int n)
 {
     int ret;
 
     d->mutex.lock();
 
-    d->value -= n;
-
+    if ( n < 0 || n > d->value ) {
 #ifdef QT_CHECK_RANGE
-    if (d->value < 0) {
-        qWarning("QSemaphore::operator-=: attempt to deallocate more resources than taken");
-        d->value = 0;
+        qWarning( "QSemaphore::operator-=: paramter %d out of range", n );
+#endif // QT_CHECK_RANGE
+        n = n < 0 ? 0 : d->value;
     }
-#endif
 
+    d->value -= n;
     ret = d->value;
 
     d->cond.wakeOne();
     d->mutex.unlock();
 
     return ret;
 }
 
 
 /*!
     Returns the number of accesses currently available to the
     semaphore.
 */
 int QSemaphore::available() const {
     int ret;
 
     d->mutex.lock();
     ret = d->max - d->value;
     d->mutex.unlock();
 
     return ret;
 }