rcc: add the ability to output copyrights in the output

According to gnu.org[1]
> When a file is automatically generated from some other file in the
> distribution, it is useful for the automatic procedure to copy the
> copyright notice and permission notice of the file it is generated
> from, if possible.

This commit allows us to add copyright notices to the .qrc files
themselves and additionally have that be output into the generated .rcc
(of which we have a few committed to the repository)

[ChangeLog][rcc] The Qt Resource Compiler now accepts a <legal> XML tag
inside the main <RCC> entry, which can be used to document the copyright
of the resource file itself and other terms of use (even though the file
is probably created by a tool like Qt Creator's resource editor). The
text of this copyright will be emitted in the generated C++ or Python
source code.

[1] https://www.gnu.org/prep/maintain/html_node/Copyright-Notices.html

Change-Id: If05cb740b64f42eba21efffd17d00417433f1ee9
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Ahmad Samir <a.samirh78@gmail.com>

src/tools/rcc/rcc.cpp

@@ -512,6 +512,12 @@ bool RCCResourceLibrary::interpretResourceFile(QIODevice *inputDevice,
                     reader.raiseError("expected <RCC> tag"_L1);
                 else
                     tokens.push(RccTag);
+            } else if (reader.name() == m_strings.TAG_LEGAL) {
+                if (tokens.isEmpty() || tokens.top() != RccTag) {
+                    reader.raiseError("unexpected <legal> tag"_L1);
+                } else {
+                    m_legal = reader.readElementText().trimmed();
+                }
             } else if (reader.name() == m_strings.TAG_RESOURCE) {
                 if (tokens.isEmpty() || tokens.top() != RccTag) {
                     reader.raiseError("unexpected <RESOURCE> tag"_L1);
@@ -1087,11 +1093,20 @@ void RCCResourceLibrary::writeNumber8(quint64 number)
 
 bool RCCResourceLibrary::writeHeader()
 {
+    auto writeCopyright = [this](QByteArrayView prefix) {
+        const QStringList lines = m_legal.split(u'\n', Qt::SkipEmptyParts);
+        for (const QString &line : lines) {
+            write(prefix.data(), prefix.size());
+            writeString(line.toUtf8().trimmed());
+            writeChar('\n');
+        }
+    };
     switch (m_format) {
     case C_Code:
     case Pass1:
         writeString("/****************************************************************************\n");
         writeString("** Resource object code\n");
+        writeCopyright("** ");
         writeString("**\n");
         writeString("** Created by: The Resource Compiler for Qt version ");
         writeByteArray(QT_VERSION_STR);
@@ -1105,6 +1120,7 @@ bool RCCResourceLibrary::writeHeader()
         break;
     case Python_Code:
         writeString("# Resource object code (Python 3)\n");
+        writeCopyright("# ");
         writeString("# Created by: object code\n");
         writeString("# Created by: The Resource Compiler for Qt version ");
         writeByteArray(QT_VERSION_STR);

src/tools/rcc/rcc.h

@@ -93,6 +93,7 @@ private:
         const QString TAG_RCC;
         const QString TAG_RESOURCE;
         const QString TAG_FILE;
+        const QString TAG_LEGAL = QLatin1StringView("legal");
         const QString ATTRIBUTE_LANG;
         const QString ATTRIBUTE_PREFIX;
         const QString ATTRIBUTE_ALIAS;
@@ -134,6 +135,7 @@ private:
     QString m_resourceRoot;
     QString m_initName;
     QString m_outputName;
+    QString m_legal;
     Format m_format;
     bool m_verbose;
     CompressionAlgorithm m_compressionAlgo;

tests/auto/tools/rcc/data/.gitattributes

@@ -0,0 +1,2 @@
+# Keep parentdir.txt with LF line endings
+parentdir.txt           -text

tests/auto/tools/rcc/data/legal/legal.qrc

@@ -0,0 +1,10 @@
+<!DOCTYPE RCC>
+<RCC version="1.0">
+    <legal>
+        Copyright (C) 2024 Intel Corporation.
+        SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+    </legal>
+    <qresource>
+        <file>../parentdir.txt</file>
+    </qresource>
+</RCC>

tests/auto/tools/rcc/data/legal/rcc_legal.cpp

@@ -0,0 +1,101 @@
+/****************************************************************************
+** Resource object code
+** Copyright (C) 2024 Intel Corporation.
+** SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+**
+** Created by: The Resource Compiler for Qt version 6.8.0
+**
+** WARNING! All changes made in this file will be lost!
+*****************************************************************************/
+
+#ifdef _MSC_VER
+// disable informational message "function ... selected for automatic inline expansion"
+#pragma warning (disable: 4711)
+#endif
+
+static const unsigned char qt_resource_data[] = {
+  // parentdir.txt
+  0x0,0x0,0x0,0x1a,
+  0x61,
+  0x62,0x63,0x64,0x65,0x66,0x67,0x69,0x68,0x6b,0x6c,0x6d,0x6e,0x6f,0x70,0x71,0x72,
+  0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0xa,
+  
+};
+
+static const unsigned char qt_resource_name[] = {
+  // parentdir.txt
+  0x0,0xd,
+  0x6,0x14,0xd1,0x74,
+  0x0,0x70,
+  0x0,0x61,0x0,0x72,0x0,0x65,0x0,0x6e,0x0,0x74,0x0,0x64,0x0,0x69,0x0,0x72,0x0,0x2e,0x0,0x74,0x0,0x78,0x0,0x74,
+  
+};
+
+static const unsigned char qt_resource_struct[] = {
+  // :
+  0x0,0x0,0x0,0x0,0x0,0x2,0x0,0x0,0x0,0x1,0x0,0x0,0x0,0x1,
+0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,
+  // :/parentdir.txt
+  0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x1,0x0,0x0,0x0,0x0,
+TIMESTAMP:../parentdir.txt
+
+};
+
+#ifdef QT_NAMESPACE
+#  define QT_RCC_PREPEND_NAMESPACE(name) ::QT_NAMESPACE::name
+#  define QT_RCC_MANGLE_NAMESPACE0(x) x
+#  define QT_RCC_MANGLE_NAMESPACE1(a, b) a##_##b
+#  define QT_RCC_MANGLE_NAMESPACE2(a, b) QT_RCC_MANGLE_NAMESPACE1(a,b)
+#  define QT_RCC_MANGLE_NAMESPACE(name) QT_RCC_MANGLE_NAMESPACE2( \
+        QT_RCC_MANGLE_NAMESPACE0(name), QT_RCC_MANGLE_NAMESPACE0(QT_NAMESPACE))
+#else
+#   define QT_RCC_PREPEND_NAMESPACE(name) name
+#   define QT_RCC_MANGLE_NAMESPACE(name) name
+#endif
+
+#if defined(QT_INLINE_NAMESPACE)
+inline namespace QT_NAMESPACE {
+#elif defined(QT_NAMESPACE)
+namespace QT_NAMESPACE {
+#endif
+
+bool qRegisterResourceData(int, const unsigned char *, const unsigned char *, const unsigned char *);
+bool qUnregisterResourceData(int, const unsigned char *, const unsigned char *, const unsigned char *);
+
+#ifdef QT_NAMESPACE
+}
+#endif
+
+int QT_RCC_MANGLE_NAMESPACE(qInitResources)();
+int QT_RCC_MANGLE_NAMESPACE(qInitResources)()
+{
+    int version = 3;
+    QT_RCC_PREPEND_NAMESPACE(qRegisterResourceData)
+        (version, qt_resource_struct, qt_resource_name, qt_resource_data);
+    return 1;
+}
+
+int QT_RCC_MANGLE_NAMESPACE(qCleanupResources)();
+int QT_RCC_MANGLE_NAMESPACE(qCleanupResources)()
+{
+    int version = 3;
+    QT_RCC_PREPEND_NAMESPACE(qUnregisterResourceData)
+       (version, qt_resource_struct, qt_resource_name, qt_resource_data);
+    return 1;
+}
+
+#ifdef __clang__
+#   pragma clang diagnostic push
+#   pragma clang diagnostic ignored "-Wexit-time-destructors"
+#endif
+
+namespace {
+   struct initializer {
+       initializer() { QT_RCC_MANGLE_NAMESPACE(qInitResources)(); }
+       ~initializer() { QT_RCC_MANGLE_NAMESPACE(qCleanupResources)(); }
+   } dummy;
+}
+
+#ifdef __clang__
+#   pragma clang diagnostic pop
+#endif

tests/auto/tools/rcc/tst_rcc.cpp

@@ -1,5 +1,6 @@
 // Copyright (C) 2012 Giuseppe D'Angelo <dangelog@gmail.com>
 // Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2024 Intel Corporation.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
 
 #include <QTest>
@@ -148,6 +149,9 @@ void tst_rcc::rcc_data()
     QTest::newRow("size-1") << sizesPath << "size-1.qrc" << "size-1.expected";
     QTest::newRow("size-2-0-35-1") << sizesPath << "size-2-0-35-1.qrc" <<
                                       (sizeof(size_t) == 8 ? "size-2-0-35-1.expected" : "size-2-0-35-1.expected32");
+
+    QTest::newRow("legal") << m_dataPath + QLatin1StringView("/legal")
+                               << "legal.qrc" << "rcc_legal.cpp";
 }
 
 static QStringList readLinesFromFile(const QString &fileName,