[Yunq] Add support for repeated nested fields

lib/glacier/container/vector.h

@@ -47,6 +47,7 @@ class Vector {
   template <typename... Args>
   void EmplaceBack(Args&&... args);
 
+  T& PeekBack();
   T&& PopBack();
 
   typedef ArrayIterator<T> Iterator;
@@ -130,6 +131,11 @@ void Vector<T>::EmplaceBack(Args&&... args) {
   data_[size_++] = T(args...);
 }
 
+template <typename T>
+T& Vector<T>::PeekBack() {
+  return data_[size_ - 1];
+}
+
 template <typename T>
 T&& Vector<T>::PopBack() {
   size_--;

lib/yunq/message_view.cpp

@@ -19,6 +19,10 @@ glcr::Status MessageView::CheckHeader() const {
   return glcr::Status::Ok();
 }
 
+uint32_t MessageView::MessageLength() const {
+  return buffer_.At<uint32_t>(offset_ + 8);
+}
+
 template <>
 glcr::ErrorOr<uint64_t> MessageView::ReadField<uint64_t>(
     uint64_t field_index) const {

lib/yunq/message_view.h

@@ -16,6 +16,7 @@ class MessageView {
       : buffer_(buffer), offset_(offset) {}
 
   [[nodiscard]] glcr::Status CheckHeader() const;
+  uint32_t MessageLength() const;
 
   // TODO: Implement glcr::StatusOr
   template <typename T>
@@ -31,6 +32,10 @@ class MessageView {
   template <typename T>
   glcr::Status ReadMessage(uint64_t field_index, T& message) const;
 
+  template <typename T>
+  glcr::Status ReadRepeatedMessage(uint64_t field_index,
+                                   glcr::Vector<T>& messages) const;
+
  private:
   const glcr::ByteBuffer& buffer_;
   uint64_t offset_;
@@ -61,4 +66,22 @@ glcr::Status MessageView::ReadMessage(uint64_t field_index, T& message) const {
   return message.ParseFromBytes(subview);
 }
 
+template <typename T>
+glcr::Status MessageView::ReadRepeatedMessage(uint64_t field_index,
+                                              glcr::Vector<T>& messages) const {
+  ExtensionPointer ptr =
+      buffer_.At<ExtensionPointer>(field_offset(field_index));
+
+  uint64_t ext_offset = ptr.offset;
+
+  while (ext_offset < ptr.offset + ptr.length) {
+    MessageView subview(buffer_, offset_ + ext_offset);
+    messages.EmplaceBack();
+    RETURN_ERROR(messages.PeekBack().ParseFromBytes(subview));
+    ext_offset += subview.MessageLength();
+  }
+
+  return glcr::Status::Ok();
+}
+
 }  // namespace yunq

lib/yunq/serialize.h

@@ -41,6 +41,9 @@ class Serializer {
   template <typename T>
   void WriteMessage(uint64_t field_index, const T& value);
 
+  template <typename T>
+  void WriteRepeatedMessage(uint64_t field_index, const glcr::Vector<T>& value);
+
   void WriteHeader();
 
   uint64_t size() const { return next_extension_; }
@@ -90,4 +93,32 @@ void Serializer::WriteMessage(uint64_t field_index, const T& value) {
   buffer_.WriteAt<ExtensionPointer>(field_offset(field_index), ptr);
 }
 
+template <typename T>
+void Serializer::WriteRepeatedMessage(uint64_t field_index,
+                                      const glcr::Vector<T>& value) {
+  uint64_t next_offset = next_extension_;
+  uint64_t length = 0;
+
+  for (T& message : value) {
+    uint64_t msg_length = 0;
+    if (caps_) {
+      msg_length = message.SerializeToBytes(buffer_, offset_ + next_offset,
+                                            caps_.value().get());
+    } else {
+      msg_length = message.SerializeToBytes(buffer_, offset_ + next_offset);
+    }
+    length += msg_length;
+    next_offset += msg_length;
+  }
+
+  ExtensionPointer ptr{
+      .offset = (uint32_t)next_extension_,
+      .length = (uint32_t)length,
+  };
+
+  next_extension_ += length;
+
+  buffer_.WriteAt<ExtensionPointer>(field_offset(field_index), ptr);
+}
+
 }  // namespace yunq