Long live QCborStreamWriter!

CBOR is the Concise Binary Object Representation, a very compact form of
binary data encoding that is compatible with JSON. It was created by the
IETF Constrained RESTful Environments (CoRE) WG[1] and has since been
used in many new RFCs by that group, especially COSE[2], and is meant to
be used alongside CoAP[3].

This API is a very simple, thin wrapper around TinyCBOR[4].

See RFC 7049 <http://tools.ietf.org/html/rfc7049>.

[1] https://datatracker.ietf.org/wg/core/charter/
[2] https://tools.ietf.org/html/rfc8152
[3] https://tools.ietf.org/html/rfc7252
[4] https://github.com/intel/tinycbor

Change-Id: Ia0aac2f09e9245339951ffff13c651cfeab77d3b
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 115 insertions, 0 deletions

diff --git a/src/corelib/serialization/qcborstream.h b/src/corelib/serialization/qcborstream.h
new file mode 100644
index 0000000000..9affe7019c
--- /dev/null
+++ b/src/corelib/serialization/qcborstream.h
@@ -0,0 +1,115 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 Intel Corporation.
+** Contact: https://www.qt.io/licensing/
+**
+** 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 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.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QCBORSTREAM_H
+#define QCBORSTREAM_H
+
+#include <QtCore/qbytearray.h>
+#include <QtCore/qcborcommon.h>
+#include <QtCore/qfloat16.h>
+#include <QtCore/qscopedpointer.h>
+#include <QtCore/qstring.h>
+#include <QtCore/qstringview.h>
+
+QT_BEGIN_NAMESPACE
+
+class QIODevice;
+
+enum class QCborNegativeInteger : quint64 {};
+
+class QCborStreamWriterPrivate;
+class Q_CORE_EXPORT QCborStreamWriter
+{
+public:
+    explicit QCborStreamWriter(QIODevice *device);
+    explicit QCborStreamWriter(QByteArray *data);
+    ~QCborStreamWriter();
+    Q_DISABLE_COPY(QCborStreamWriter)
+
+    void setDevice(QIODevice *device);
+    QIODevice *device() const;
+
+    void append(quint64 u);
+    void append(qint64 i);
+    void append(QCborNegativeInteger n);
+    void append(const QByteArray &ba)       { appendByteString(ba.constData(), ba.size()); }
+    void append(QLatin1String str);
+    void append(QStringView str);
+    void append(QCborTag tag);
+    void append(QCborKnownTags tag)         { append(QCborTag(tag)); }
+    void append(QCborSimpleType st);
+    void append(std::nullptr_t)             { append(QCborSimpleType::Null); }
+    void append(qfloat16 f);
+    void append(float f);
+    void append(double d);
+
+    void appendByteString(const char *data, qsizetype len);
+    void appendTextString(const char *utf8, qsizetype len);
+
+    // convenience
+    void append(bool b)     { append(b ? QCborSimpleType::True : QCborSimpleType::False); }
+    void appendNull()       { append(QCborSimpleType::Null); }
+    void appendUndefined()  { append(QCborSimpleType::Undefined); }
+
+#ifndef Q_QDOC
+    // overloads to make normal code not complain
+    void append(int i)      { append(qint64(i)); }
+    void append(uint u)     { append(quint64(u)); }
+#endif
+#ifndef QT_NO_CAST_FROM_ASCII
+    void append(const char *str, qsizetype size = -1)
+    { appendTextString(str, (str && size == -1)  ? int(strlen(str)) : size); }
+#endif
+
+    void startArray();
+    void startArray(quint64 count);
+    bool endArray();
+    void startMap();
+    void startMap(quint64 count);
+    bool endMap();
+
+    // no API for encoding chunked strings
+
+private:
+    QScopedPointer<QCborStreamWriterPrivate> d;
+};
+
+QT_END_NAMESPACE
+
+#endif // QCBORSTREAM_H