intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 72 insertions, 0 deletions

diff --git a/library/cpp/protobuf/util/walk.cpp b/library/cpp/protobuf/util/walk.cpp
new file mode 100644
index 0000000000..b65ec03e04
--- /dev/null
+++ b/library/cpp/protobuf/util/walk.cpp
@@ -0,0 +1,72 @@
+#include "walk.h"
+
+#include <util/generic/hash_set.h>
+
+namespace {
+    using namespace NProtoBuf;
+
+    template <typename TMessage, typename TOnField>
+    void DoWalkReflection(TMessage& msg, TOnField& onField) {
+        const Descriptor* descr = msg.GetDescriptor();
+        for (int i1 = 0; i1 < descr->field_count(); ++i1) {
+            const FieldDescriptor* fd = descr->field(i1);
+            if (!onField(msg, fd)) {
+                continue;
+            }
+
+            std::conditional_t<std::is_const_v<TMessage>, TConstField, TMutableField> ff(msg, fd);
+            if (ff.IsMessage()) {
+                for (size_t i2 = 0; i2 < ff.Size(); ++i2) {
+                    if constexpr (std::is_const_v<TMessage>) {
+                        WalkReflection(*ff.template Get<Message>(i2), onField);
+                    } else {
+                        WalkReflection(*ff.MutableMessage(i2), onField);
+                    }
+                }
+            }
+        }
+    }
+
+    void DoWalkSchema(const Descriptor* descriptor,
+                      std::function<bool(const FieldDescriptor*)>& onField,
+                      THashSet<const Descriptor*>& visited)
+    {
+        if (!visited.emplace(descriptor).second) {
+            return;
+        }
+        for (int i1 = 0; i1 < descriptor->field_count(); ++i1) {
+            const FieldDescriptor* fd = descriptor->field(i1);
+            if (!onField(fd)) {
+                continue;
+            }
+
+            if (fd->type() == FieldDescriptor::Type::TYPE_MESSAGE) {
+                DoWalkSchema(fd->message_type(), onField, visited);
+            }
+        }
+        visited.erase(descriptor);
+    }
+
+}
+
+namespace NProtoBuf {
+    void WalkReflection(Message& msg,
+                        std::function<bool(Message&, const FieldDescriptor*)> onField) 
+    {
+        DoWalkReflection(msg, onField);
+    }
+
+    void WalkReflection(const Message& msg,
+                        std::function<bool(const Message&, const FieldDescriptor*)> onField)
+    {
+        DoWalkReflection(msg, onField);
+    }
+
+    void WalkSchema(const Descriptor* descriptor,
+                    std::function<bool(const FieldDescriptor*)> onField) 
+    {
+        THashSet<const Descriptor*> visited;
+        DoWalkSchema(descriptor, onField, visited);
+    }
+
+} // namespace NProtoBuf