1 files changed, 91 insertions, 0 deletions
diff --git a/src/rocksdb/db/history_trimming_iterator.h b/src/rocksdb/db/history_trimming_iterator.h
new file mode 100644
index 000000000..b445ced33
--- /dev/null
+++ b/src/rocksdb/db/history_trimming_iterator.h
@@ -0,0 +1,91 @@
+// Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include "db/dbformat.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/slice.h"
+#include "table/internal_iterator.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+class HistoryTrimmingIterator : public InternalIterator {
+ public:
+  explicit HistoryTrimmingIterator(InternalIterator* input,
+                                   const Comparator* cmp, const std::string& ts)
+      : input_(input), filter_ts_(ts), cmp_(cmp) {
+    assert(cmp_->timestamp_size() > 0 && !ts.empty());
+  }
+
+  bool filter() const {
+    if (!input_->Valid()) {
+      return true;
+    }
+    Slice current_ts = ExtractTimestampFromKey(key(), cmp_->timestamp_size());
+    return cmp_->CompareTimestamp(current_ts, Slice(filter_ts_)) <= 0;
+  }
+
+  bool Valid() const override { return input_->Valid(); }
+
+  void SeekToFirst() override {
+    input_->SeekToFirst();
+    while (!filter()) {
+      input_->Next();
+    }
+  }
+
+  void SeekToLast() override {
+    input_->SeekToLast();
+    while (!filter()) {
+      input_->Prev();
+    }
+  }
+
+  void Seek(const Slice& target) override {
+    input_->Seek(target);
+    while (!filter()) {
+      input_->Next();
+    }
+  }
+
+  void SeekForPrev(const Slice& target) override {
+    input_->SeekForPrev(target);
+    while (!filter()) {
+      input_->Prev();
+    }
+  }
+
+  void Next() override {
+    do {
+      input_->Next();
+    } while (!filter());
+  }
+
+  void Prev() override {
+    do {
+      input_->Prev();
+    } while (!filter());
+  }
+
+  Slice key() const override { return input_->key(); }
+
+  Slice value() const override { return input_->value(); }
+
+  Status status() const override { return input_->status(); }
+
+  bool IsKeyPinned() const override { return input_->IsKeyPinned(); }
+
+  bool IsValuePinned() const override { return input_->IsValuePinned(); }
+
+ private:
+  InternalIterator* input_;
+  const std::string filter_ts_;
+  const Comparator* const cmp_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE