1 files changed, 25 insertions, 55 deletions

diff --git a/src/corelib/doc/snippets/qloggingcategory/main.cpp b/src/corelib/doc/snippets/qloggingcategory/main.cpp
index f5c47b2ae8..8b3a61d51f 100644
--- a/src/corelib/doc/snippets/qloggingcategory/main.cpp
+++ b/src/corelib/doc/snippets/qloggingcategory/main.cpp
@@ -1,52 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the documentation of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:BSD$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** BSD License Usage
-** Alternatively, you may use this file under the terms of the BSD license
-** as follows:
-**
-** "Redistribution and use in source and binary forms, with or without
-** modification, are permitted provided that the following conditions are
-** met:
-**   * Redistributions of source code must retain the above copyright
-**     notice, this list of conditions and the following disclaimer.
-**   * Redistributions in binary form must reproduce the above copyright
-**     notice, this list of conditions and the following disclaimer in
-**     the documentation and/or other materials provided with the
-**     distribution.
-**   * Neither the name of The Qt Company Ltd nor the names of its
-**     contributors may be used to endorse or promote products derived
-**     from this software without specific prior written permission.
-**
-**
-** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
 #include <QCoreApplication>
 #include <QLoggingCategory>
@@ -86,15 +39,20 @@ void myCategoryFilter(QLoggingCategory *);
 //![20]
 
 //![21]
-QLoggingCategory::CategoryFilter oldCategoryFilter;
+static QLoggingCategory::CategoryFilter oldCategoryFilter = nullptr;
 
 void myCategoryFilter(QLoggingCategory *category)
 {
-    // configure driver.usb category here, otherwise forward to to default filter.
+    // For a category set up after this filter is installed, we first set it up
+    // with the old filter. This ensures that any driver.usb logging configured
+    // by the user is kept, aside from the one level we override; and any new
+    // categories we're not interested in get configured by the old filter.
+    if (oldCategoryFilter)
+        oldCategoryFilter(category);
+
+    // Tweak driver.usb's logging, over-riding the default filter:
     if (qstrcmp(category->categoryName(), "driver.usb") == 0)
         category->setEnabled(QtDebugMsg, true);
-    else
-        oldCategoryFilter(category);
 }
 //![21]
 
@@ -107,8 +65,6 @@ int main(int argc, char *argv[])
 //![2]
 
 //![22]
-
-// ...
 oldCategoryFilter = QLoggingCategory::installFilter(myCategoryFilter);
 //![22]
 
@@ -175,6 +131,20 @@ oldCategoryFilter = QLoggingCategory::installFilter(myCategoryFilter);
 //![15]
     }
 
+    {
+//![16]
+    QLoggingCategory category("driver.usb");
+    qCFatal(category) << "a fatal message. Program will be terminated!";
+//![16]
+    }
+
+    {
+//![17]
+    QLoggingCategory category("driver.usb");
+    qCFatal(category, "a fatal message. Program will be terminated!");
+//![17]
+    }
+
     return 0;
 }