64 bit for mark

fandreuz · fandreuz · commit 17084feb8264 · 2025-06-11T09:05:11.000Z
diff --git a/src/protobuf.cpp b/src/protobuf.cpp
@@ -74,30 +74,33 @@ protobuf_mark_t ProtoBuffer::startMessage(protobuf_index_t index, size_t len_byt
 
     ensureCapacity(len_byte_count);
 
-    protobuf_mark_t mark{_offset, len_byte_count};
+    protobuf_mark_t mark = _offset << 3 | len_byte_count;
     _offset += len_byte_count;
     return mark;
 }
 
 void ProtoBuffer::commitMessage(const protobuf_mark_t& mark) {
-    size_t actual_len = _offset - (mark.message_start + mark.expected_len_byte_count);
+    u32 expected_len_byte_count = mark & 7;
+    u32 message_start = mark >> 3;
+
+    size_t actual_len = _offset - (message_start + expected_len_byte_count);
     size_t actual_len_byte_count = varIntSize(actual_len);
-    if (actual_len_byte_count > mark.expected_len_byte_count) {
-        _offset = mark.message_start;
-        // The tag is already accounted for before mark.message_start
+    if (actual_len_byte_count > expected_len_byte_count) {
+        _offset = message_start;
+        // The tag is already accounted for before message_start
         ensureCapacity(actual_len_byte_count + actual_len);
-        memmove(_data + mark.message_start + actual_len_byte_count,
-                _data + mark.message_start + mark.expected_len_byte_count,
+        memmove(_data + message_start + actual_len_byte_count,
+                _data + message_start + expected_len_byte_count,
                 actual_len);
-        _offset = mark.message_start + actual_len_byte_count + actual_len;
+        _offset = message_start + actual_len_byte_count + actual_len;
     } else {
-        actual_len_byte_count = mark.expected_len_byte_count;
+        actual_len_byte_count = expected_len_byte_count;
     }
 
     for (size_t i = 0; i < actual_len_byte_count - 1; ++i) {
-        size_t idx = mark.message_start + i;
+        size_t idx = message_start + i;
         _data[idx] = (unsigned char) (0x80 | (actual_len & 0x7f));
         actual_len >>= 7;
     }
-    _data[mark.message_start + actual_len_byte_count - 1] = (unsigned char) actual_len;
+    _data[message_start + actual_len_byte_count - 1] = (unsigned char) actual_len;
 }
diff --git a/src/protobuf.h b/src/protobuf.h
@@ -14,10 +14,9 @@ protobuf_t VARINT = 0;
 protobuf_t LEN = 2;
 
 typedef u32 protobuf_index_t;
-struct protobuf_mark_t {
-    size_t message_start;
-    size_t expected_len_byte_count;
-};
+// 3 bits for requested byte count for the message size
+// 61 bits for the message start
+typedef u64 protobuf_mark_t;
 
 const size_t NESTED_FIELD_BYTE_COUNT = 5;
 const size_t MINIMUM_INITIAL_SIZE = 16;
diff --git a/test/native/protobufBufferTest.cpp b/test/native/protobufBufferTest.cpp
@@ -90,7 +90,7 @@ TEST_CASE(Buffer_test_string) {
 TEST_CASE(Buffer_test_nestedField) {
     ProtoBuffer buf(100);
 
-    protobuf_mark_t mark = buf.startMessage(4);
+    protobuf_mark_t mark = buf.startMessage(4, 3);
     buf.field(3, (u64)10);
     buf.field(5, true);
     buf.commitMessage(mark);
@@ -109,8 +109,8 @@ TEST_CASE(Buffer_test_nestedField) {
 TEST_CASE(Buffer_test_nestedMessageWithString) {
     ProtoBuffer buf(100);
 
-    protobuf_mark_t mark1 = buf.startMessage(3);
-    protobuf_mark_t mark2 = buf.startMessage(4);
+    protobuf_mark_t mark1 = buf.startMessage(3, 3);
+    protobuf_mark_t mark2 = buf.startMessage(4, 3);
     buf.field(5, "ciao");
     buf.commitMessage(mark1);
     buf.commitMessage(mark2);
