1 files changed, 120 insertions, 0 deletions
diff --git a/src/rocksdb/utilities/merge_operators.cc b/src/rocksdb/utilities/merge_operators.cc
new file mode 100644
index 000000000..c97e9ce25
--- /dev/null
+++ b/src/rocksdb/utilities/merge_operators.cc
@@ -0,0 +1,120 @@
+// Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "utilities/merge_operators.h"
+
+#include <memory>
+
+#include "rocksdb/merge_operator.h"
+#include "rocksdb/options.h"
+#include "rocksdb/utilities/customizable_util.h"
+#include "rocksdb/utilities/object_registry.h"
+#include "utilities/merge_operators/bytesxor.h"
+#include "utilities/merge_operators/sortlist.h"
+#include "utilities/merge_operators/string_append/stringappend.h"
+#include "utilities/merge_operators/string_append/stringappend2.h"
+
+namespace ROCKSDB_NAMESPACE {
+static bool LoadMergeOperator(const std::string& id,
+                              std::shared_ptr<MergeOperator>* result) {
+  bool success = true;
+  // TODO: Hook the "name" up to the actual Name() of the MergeOperators?
+  // Requires these classes be moved into a header file...
+  if (id == "put" || id == "PutOperator") {
+    *result = MergeOperators::CreatePutOperator();
+  } else if (id == "put_v1") {
+    *result = MergeOperators::CreateDeprecatedPutOperator();
+  } else if (id == "uint64add" || id == "UInt64AddOperator") {
+    *result = MergeOperators::CreateUInt64AddOperator();
+  } else if (id == "max" || id == "MaxOperator") {
+    *result = MergeOperators::CreateMaxOperator();
+#ifdef ROCKSDB_LITE
+    // The remainder of the classes are handled by the ObjectRegistry in
+    // non-LITE mode
+  } else if (id == StringAppendOperator::kNickName() ||
+             id == StringAppendOperator::kClassName()) {
+    *result = MergeOperators::CreateStringAppendOperator();
+  } else if (id == StringAppendTESTOperator::kNickName() ||
+             id == StringAppendTESTOperator::kClassName()) {
+    *result = MergeOperators::CreateStringAppendTESTOperator();
+  } else if (id == BytesXOROperator::kNickName() ||
+             id == BytesXOROperator::kClassName()) {
+    *result = MergeOperators::CreateBytesXOROperator();
+  } else if (id == SortList::kNickName() || id == SortList::kClassName()) {
+    *result = MergeOperators::CreateSortOperator();
+#endif  // ROCKSDB_LITE
+  } else {
+    success = false;
+  }
+  return success;
+}
+
+#ifndef ROCKSDB_LITE
+static int RegisterBuiltinMergeOperators(ObjectLibrary& library,
+                                         const std::string& /*arg*/) {
+  size_t num_types;
+  library.AddFactory<MergeOperator>(
+      ObjectLibrary::PatternEntry(StringAppendOperator::kClassName())
+          .AnotherName(StringAppendOperator::kNickName()),
+      [](const std::string& /*uri*/, std::unique_ptr<MergeOperator>* guard,
+         std::string* /*errmsg*/) {
+        guard->reset(new StringAppendOperator(","));
+        return guard->get();
+      });
+  library.AddFactory<MergeOperator>(
+      ObjectLibrary::PatternEntry(StringAppendTESTOperator::kClassName())
+          .AnotherName(StringAppendTESTOperator::kNickName()),
+      [](const std::string& /*uri*/, std::unique_ptr<MergeOperator>* guard,
+         std::string* /*errmsg*/) {
+        guard->reset(new StringAppendTESTOperator(","));
+        return guard->get();
+      });
+  library.AddFactory<MergeOperator>(
+      ObjectLibrary::PatternEntry(SortList::kClassName())
+          .AnotherName(SortList::kNickName()),
+      [](const std::string& /*uri*/, std::unique_ptr<MergeOperator>* guard,
+         std::string* /*errmsg*/) {
+        guard->reset(new SortList());
+        return guard->get();
+      });
+  library.AddFactory<MergeOperator>(
+      ObjectLibrary::PatternEntry(BytesXOROperator::kClassName())
+          .AnotherName(BytesXOROperator::kNickName()),
+      [](const std::string& /*uri*/, std::unique_ptr<MergeOperator>* guard,
+         std::string* /*errmsg*/) {
+        guard->reset(new BytesXOROperator());
+        return guard->get();
+      });
+
+  return static_cast<int>(library.GetFactoryCount(&num_types));
+}
+#endif  // ROCKSDB_LITE
+
+Status MergeOperator::CreateFromString(const ConfigOptions& config_options,
+                                       const std::string& value,
+                                       std::shared_ptr<MergeOperator>* result) {
+#ifndef ROCKSDB_LITE
+  static std::once_flag once;
+  std::call_once(once, [&]() {
+    RegisterBuiltinMergeOperators(*(ObjectLibrary::Default().get()), "");
+  });
+#endif  // ROCKSDB_LITE
+  return LoadSharedObject<MergeOperator>(config_options, value,
+                                         LoadMergeOperator, result);
+}
+
+std::shared_ptr<MergeOperator> MergeOperators::CreateFromStringId(
+    const std::string& id) {
+  std::shared_ptr<MergeOperator> result;
+  Status s = MergeOperator::CreateFromString(ConfigOptions(), id, &result);
+  if (s.ok()) {
+    return result;
+  } else {
+    // Empty or unknown, just return nullptr
+    return nullptr;
+  }
+}
+
+}  // namespace ROCKSDB_NAMESPACE