Add support for field flags

Add the additional field to the property ordering structure to
indicate the special attributes that the message fields may have,
e.g. the 'packed' attribute.

Task-number: QTBUG-103979
Change-Id: I62c974cc924011956feb7692d6cb4fcd072dc1e6
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

src/protobuf/qtprotobuftypes.cpp

@@ -61,6 +61,12 @@ namespace QtProtobufPrivate {
         return -1;
     }
 
+    uint QProtobufPropertyOrdering::getFieldFlags(int index) const
+    {
+        Q_ASSERT(data);
+        return uint_dataForIndex(index, data->flagsOffset);
+    }
+
     const uint *QProtobufPropertyOrdering::uint_data() const
     {
         Q_ASSERT(data);
@@ -79,7 +85,7 @@ namespace QtProtobufPrivate {
     const char *QProtobufPropertyOrdering::char_data() const
     {
         Q_ASSERT(data);
-        const uint LastOffset = data->propertyIndexOffset;
+        const uint LastOffset = data->flagsOffset;
         const uint *u_data = &uint_dataForIndex(int(data->numFields - 1), LastOffset);
         ++u_data;
         quintptr uptr_data = quintptr(u_data);

src/protobuf/qtprotobuftypes.h

@@ -22,6 +22,8 @@ QT_BEGIN_NAMESPACE
 
 namespace QtProtobufPrivate {
 
+enum FieldFlag : uint { NoFlags = 0x0 };
+
 struct QProtobufPropertyOrdering
 {
     const struct Data {
@@ -29,11 +31,13 @@ struct QProtobufPropertyOrdering
         uint numFields;
         uint fieldNumberOffset;
         uint propertyIndexOffset;
+        uint flagsOffset;
     } *data;
 
     Q_PROTOBUF_EXPORT QUtf8StringView getJsonName(int index) const;
     Q_PROTOBUF_EXPORT int getFieldNumber(int index) const;
     Q_PROTOBUF_EXPORT int getPropertyIndex(int index) const;
+    Q_PROTOBUF_EXPORT uint getFieldFlags(int index) const;
     Q_PROTOBUF_EXPORT int indexOfFieldNumber(int fieldNumber) const;
     inline int fieldCount() const { return int(data->numFields); }
 private:
@@ -58,6 +62,7 @@ struct QProtobufPropertyOrderingInfo
         return (overrideFieldNumber >= 0) ? overrideFieldNumber : ordering.getFieldNumber(index);
     }
     inline int getPropertyIndex() const { return ordering.getPropertyIndex(index); }
+    inline uint getFieldFlags() const { return ordering.getFieldFlags(index); }
 
     // Needed for maps, which uses field number 1 and 2 for key and value respectively
     QProtobufPropertyOrderingInfo infoForMapKey() const { return { ordering, index, 1 }; }

src/tools/qtprotobufgen/generatorcommon.cpp

@@ -488,3 +488,21 @@ const Descriptor *common::findHighestMessage(const Descriptor *message)
         highestMessage = highestMessage->containing_type();
     return highestMessage;
 }
+
+std::string common::collectFieldFlags([[maybe_unused]] const FieldDescriptor *field)
+{
+    std::string_view separator = " | ";
+    std::string_view active_separator;
+    std::string flags;
+
+    auto writeFlag = [&](const char *flag) {
+        flags += active_separator;
+        flags += "QtProtobufPrivate::";
+        flags += flag;
+        active_separator = separator;
+    };
+
+    writeFlag("NoFlags");
+
+    return flags;
+}

src/tools/qtprotobufgen/generatorcommon.h

@@ -81,6 +81,8 @@ struct common {
 
     static bool isNested(const Descriptor *message);
     static const Descriptor *findHighestMessage(const Descriptor *message);
+
+    static std::string collectFieldFlags(const google::protobuf::FieldDescriptor *field);
 };
 } // namespace QtProtobuf::generator
 

src/tools/qtprotobufgen/messagedefinitionprinter.cpp

@@ -7,6 +7,7 @@
 #include <google/protobuf/descriptor.h>
 #include "options.h"
 #include "templates.h"
+#include "generatorcommon.h"
 
 #include <cassert>
 
@@ -86,7 +87,7 @@ void MessageDefinitionPrinter::printRegisterBody()
 void MessageDefinitionPrinter::printFieldsOrdering()
 {
     const int fieldCount = m_descriptor->field_count();
-    constexpr int MetaFieldsCount = 3;
+    constexpr int MetaFieldsCount = 4;
     constexpr int Version = 0;
 
     int uint_dataOffset = 1; // the json name offsets are always stored at offset 0
@@ -100,6 +101,8 @@ void MessageDefinitionPrinter::printFieldsOrdering()
         // +1 for EOS offset in JSON data
         { "property_index_offset", std::to_string(fieldCount * (uint_dataOffset++) + 1) },
         // +1 for EOS offset in JSON data
+        { "field_flags_offset", std::to_string(fieldCount * (uint_dataOffset++) + 1) },
+        // +1 for EOS offset in JSON data
         { "uint_size", std::to_string(fieldCount * MetaFieldsCount + 1) },
         { "char_size", std::to_string(char_dataSize) },
     };
@@ -125,6 +128,9 @@ void MessageDefinitionPrinter::printFieldsOrdering()
     m_printer->Print("// Property indices:\n");
     printUintData(Templates::QtPropertyIndicesUintDataTemplate());
 
+    m_printer->Print("// Field flags:\n");
+    printUintData(Templates::FieldFlagsUintDataTemplate());
+
     Outdent();
     m_printer->Print("},\n");
 
@@ -150,6 +156,7 @@ void MessageDefinitionPrinter::printUintData(const char *templateString)
             { "json_name_offset", std::to_string(jsonOffset) },
             { "field_number", std::to_string(field->number()) },
             { "property_index", std::to_string(++index) },
+            { "field_flags", common::collectFieldFlags(field) },
             { "json_name", field->json_name() },
         };
         m_printer->Print(variables, templateString);

src/tools/qtprotobufgen/templates.cpp

@@ -552,6 +552,11 @@ const char *Templates::QtPropertyIndicesUintDataTemplate()
     return "$property_index$, /* = $json_name$ */\n";
 }
 
+const char *Templates::FieldFlagsUintDataTemplate()
+{
+    return "$field_flags$, /* = $json_name$ */\n";
+}
+
 const char *Templates::PropertyOrderingDataOpeningTemplate()
 {
     return "static constexpr struct {\n"
@@ -565,6 +570,7 @@ const char *Templates::PropertyOrderingDataOpeningTemplate()
            "        $num_fields$, /* = num fields */\n"
            "        $field_number_offset$, /* = field number offset */\n"
            "        $property_index_offset$, /* = property index offset */\n"
+           "        $field_flags_offset$, /* = field flags offset */\n"
            "    },\n";
 }
 

src/tools/qtprotobufgen/templates.h

@@ -117,6 +117,7 @@ public:
     static const char *JsonNameOffsetsUintDataTemplate();
     static const char *FieldNumbersUintDataTemplate();
     static const char *QtPropertyIndicesUintDataTemplate();
+    static const char *FieldFlagsUintDataTemplate();
     static const char *PropertyOrderingDataOpeningTemplate();
     static const char *PropertyOrderingDataClosingTemplate();
     static const char *PropertyOrderingDefinitionTemplate();