[ntuple] Week 1: Register kTypeS3 = 0x03 locator type

Author: JasMehta08

tree/ntuple/inc/ROOT/RNTupleTypes.hxx

@@ -236,6 +236,7 @@ public:
       // if the size of the referenced data block is >2GB
       kTypeFile = 0x00,
       kTypeDAOS = 0x02,
+      kTypeS3 = 0x03,
 
       kLastSerializableType = 0x7f,
       kTypePageZero = kLastSerializableType + 1,

tree/ntuple/src/RNTupleSerialize.cxx

@@ -505,7 +505,7 @@ ROOT::RResult<void> DeserializeLocatorPayloadObject64(const unsigned char *buffe
       locator.SetNBytesOnStorage(nBytesOnStorage);
       RNTupleSerializer::DeserializeUInt64(buffer + sizeof(std::uint64_t), location);
    } else {
-      return R__FAIL("invalid DAOS locator payload size: " + std::to_string(sizeofLocatorPayload));
+      return R__FAIL("invalid Object64 locator payload size: " + std::to_string(sizeofLocatorPayload));
    }
    locator.SetPosition(ROOT::RNTupleLocatorObject64{location});
    return ROOT::RResult<void>::Success();
@@ -1090,6 +1090,10 @@ ROOT::Internal::RNTupleSerializer::SerializeLocator(const RNTupleLocator &locato
       size += SerializeLocatorPayloadObject64(locator, payloadp);
       locatorType = 0x02;
       break;
+   case RNTupleLocator::kTypeS3:
+      size += SerializeLocatorPayloadObject64(locator, payloadp);
+      locatorType = 0x03;
+      break;
    default:
       if (locator.GetType() == ROOT::Internal::kTestLocatorType) {
          // For the testing locator, use the same payload format as Object64. We won't read it back anyway.
@@ -1138,6 +1142,10 @@ ROOT::RResult<std::uint32_t> ROOT::Internal::RNTupleSerializer::DeserializeLocat
          locator.SetType(RNTupleLocator::kTypeDAOS);
          DeserializeLocatorPayloadObject64(bytes, payloadSize, locator);
          break;
+      case 0x03:
+         locator.SetType(RNTupleLocator::kTypeS3);
+         DeserializeLocatorPayloadObject64(bytes, payloadSize, locator);
+         break;
       default: locator.SetType(RNTupleLocator::kTypeUnknown);
       }
       bytes += payloadSize;

tree/ntuple/test/ntuple_serialize.cxx

@@ -399,6 +399,31 @@ TEST(RNTuple, SerializeLocator)
    EXPECT_EQ(locator.GetReserved(), 1);
    EXPECT_EQ(1337U, locator.GetPosition<RNTupleLocatorObject64>().GetLocation());
 
+   // S3 locator round-trip with 32-bit nBytesOnStorage
+   locator = RNTupleLocator{};
+   locator.SetType(RNTupleLocator::kTypeS3);
+   locator.SetPosition(RNTupleLocatorObject64{42U});
+   locator.SetNBytesOnStorage(1024U);
+   locator.SetReserved(0);
+   EXPECT_EQ(16u, RNTupleSerializer::SerializeLocator(locator, buffer).Unwrap());
+   locator = RNTupleLocator{};
+   EXPECT_EQ(16u, RNTupleSerializer::DeserializeLocator(buffer, 16, locator).Unwrap());
+   EXPECT_EQ(locator.GetType(), RNTupleLocator::kTypeS3);
+   EXPECT_EQ(locator.GetNBytesOnStorage(), 1024U);
+   EXPECT_EQ(locator.GetReserved(), 0);
+   EXPECT_EQ(42U, locator.GetPosition<RNTupleLocatorObject64>().GetLocation());
+
+   // S3 locator round-trip with 64-bit nBytesOnStorage and reserved bit
+   locator.SetNBytesOnStorage(static_cast<std::uint64_t>(std::numeric_limits<std::uint32_t>::max()) + 1);
+   locator.SetReserved(1);
+   EXPECT_EQ(20u, RNTupleSerializer::SerializeLocator(locator, buffer).Unwrap());
+   locator = RNTupleLocator{};
+   EXPECT_EQ(20u, RNTupleSerializer::DeserializeLocator(buffer, 20, locator).Unwrap());
+   EXPECT_EQ(locator.GetType(), RNTupleLocator::kTypeS3);
+   EXPECT_EQ(locator.GetNBytesOnStorage(), static_cast<std::uint64_t>(std::numeric_limits<std::uint32_t>::max()) + 1);
+   EXPECT_EQ(locator.GetReserved(), 1);
+   EXPECT_EQ(42U, locator.GetPosition<RNTupleLocatorObject64>().GetLocation());
+
    std::int32_t *head = reinterpret_cast<std::int32_t *>(buffer);
 #ifndef R__BYTESWAP
    // on big endian system