Import qlogger framework

Merge most parts of the qlogger framework from

git://gitorious.org/qtplayground/qlogger.git

The categorized logging feature is a replacement for qDebug, qWarning and
friends. With logging statements in an app/library, a developer can
turn on the statements they care about and turn off the ones they don't.

Most work for this was done by Wolfgang Beck and Lincoln Ramsay.

Task-number: QTBUG-25694
Change-Id: Ib0cdfbbf3694f86ad9ec553b2ea36f09a477cded
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 138 insertions, 0 deletions

diff --git a/src/corelib/io/qloggingcategory.h b/src/corelib/io/qloggingcategory.h
new file mode 100644
index 0000000000..90111c96fa
--- /dev/null
+++ b/src/corelib/io/qloggingcategory.h
@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QLOGGINGCATEGORY_H
+#define QLOGGINGCATEGORY_H
+
+#include <QtCore/qglobal.h>
+#include <QtCore/qdebug.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_CORE_EXPORT QLoggingCategory
+{
+    Q_DISABLE_COPY(QLoggingCategory)
+public:
+    explicit QLoggingCategory(const char *category);
+    ~QLoggingCategory();
+
+    template <QtMsgType T>
+    bool isEnabled() const
+    {
+        return isEnabled(T);
+    }
+
+    bool isEnabled(QtMsgType type) const;
+    void setEnabled(QtMsgType type, bool enable);
+
+    const char *categoryName() const { return name; }
+
+    // allows usage of both factory method and variable in qCX macros
+    QLoggingCategory &operator()() { return *this; }
+
+    static QLoggingCategory &defaultCategory();
+
+    typedef void (*CategoryFilter)(QLoggingCategory*);
+    static CategoryFilter installFilter(CategoryFilter);
+
+    static void setFilterRules(const QString &rules);
+
+private:
+    const char *name;
+
+    bool enabledDebug;
+    bool enabledWarning;
+    bool enabledCritical;
+
+    friend class QLoggingRegistry;
+};
+
+template <>
+inline bool QLoggingCategory::isEnabled<QtDebugMsg>() const
+{
+    return enabledDebug;
+}
+
+template <>
+inline bool QLoggingCategory::isEnabled<QtWarningMsg>() const
+{
+    return enabledWarning;
+}
+
+template <>
+inline bool QLoggingCategory::isEnabled<QtCriticalMsg>() const
+{
+    return enabledCritical;
+}
+
+#define Q_DECLARE_LOGGING_CATEGORY(name) \
+    extern QLoggingCategory &name();
+
+// relies on QLoggingCategory(QString) being thread safe!
+#define Q_LOGGING_CATEGORY(name, string) \
+    QLoggingCategory &name() \
+    { \
+        static QLoggingCategory category(string); \
+        return category; \
+    }
+
+#define qCDebug(category) \
+    for (bool enabled = category().isEnabled<QtDebugMsg>(); enabled; enabled = false) \
+        QMessageLogger(__FILE__, __LINE__, Q_FUNC_INFO, category().categoryName()).debug()
+#define qCWarning(category) \
+    for (bool enabled = category().isEnabled<QtWarningMsg>(); enabled; enabled = false) \
+        QMessageLogger(__FILE__, __LINE__, Q_FUNC_INFO, category().categoryName()).warning()
+#define qCCritical(category) \
+    for (bool enabled = category().isEnabled<QtCriticalMsg>(); enabled; enabled = false) \
+        QMessageLogger(__FILE__, __LINE__, Q_FUNC_INFO, category().categoryName()).critical()
+
+#if defined(QT_NO_DEBUG_OUTPUT)
+#  undef qCDebug
+#  define qCDebug(category) QT_NO_QDEBUG_MACRO()
+#endif
+#if defined(QT_NO_WARNING_OUTPUT)
+#  undef qCWarning
+#  define qCWarning(category) QT_NO_QWARNING_MACRO()
+#endif
+
+QT_END_NAMESPACE
+
+#endif // QLOGGINGCATEGORY_H