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+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Slow stream implementations, mainly for testing and benchmarking
+
+#pragma once
+
+#include <cstdint>
+#include <memory>
+#include <utility>
+
+#include "arrow/io/interfaces.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+
+class Buffer;
+class Status;
+
+namespace io {
+
+class ARROW_EXPORT LatencyGenerator {
+ public:
+  virtual ~LatencyGenerator();
+
+  void Sleep();
+
+  virtual double NextLatency() = 0;
+
+  static std::shared_ptr<LatencyGenerator> Make(double average_latency);
+  static std::shared_ptr<LatencyGenerator> Make(double average_latency, int32_t seed);
+};
+
+// XXX use ConcurrencyWrapper?  It could increase chances of finding a race.
+
+template <class StreamType>
+class SlowInputStreamBase : public StreamType {
+ public:
+  SlowInputStreamBase(std::shared_ptr<StreamType> stream,
+                      std::shared_ptr<LatencyGenerator> latencies)
+      : stream_(std::move(stream)), latencies_(std::move(latencies)) {}
+
+  SlowInputStreamBase(std::shared_ptr<StreamType> stream, double average_latency)
+      : stream_(std::move(stream)), latencies_(LatencyGenerator::Make(average_latency)) {}
+
+  SlowInputStreamBase(std::shared_ptr<StreamType> stream, double average_latency,
+                      int32_t seed)
+      : stream_(std::move(stream)),
+        latencies_(LatencyGenerator::Make(average_latency, seed)) {}
+
+ protected:
+  std::shared_ptr<StreamType> stream_;
+  std::shared_ptr<LatencyGenerator> latencies_;
+};
+
+/// \brief An InputStream wrapper that makes reads slower.
+///
+/// Read() calls are made slower by an average latency (in seconds).
+/// Actual latencies form a normal distribution closely centered
+/// on the average latency.
+/// Other calls are forwarded directly.
+class ARROW_EXPORT SlowInputStream : public SlowInputStreamBase<InputStream> {
+ public:
+  ~SlowInputStream() override;
+
+  using SlowInputStreamBase<InputStream>::SlowInputStreamBase;
+
+  Status Close() override;
+  Status Abort() override;
+  bool closed() const override;
+
+  Result<int64_t> Read(int64_t nbytes, void* out) override;
+  Result<std::shared_ptr<Buffer>> Read(int64_t nbytes) override;
+  Result<util::string_view> Peek(int64_t nbytes) override;
+
+  Result<int64_t> Tell() const override;
+};
+
+/// \brief A RandomAccessFile wrapper that makes reads slower.
+///
+/// Similar to SlowInputStream, but allows random access and seeking.
+class ARROW_EXPORT SlowRandomAccessFile : public SlowInputStreamBase<RandomAccessFile> {
+ public:
+  ~SlowRandomAccessFile() override;
+
+  using SlowInputStreamBase<RandomAccessFile>::SlowInputStreamBase;
+
+  Status Close() override;
+  Status Abort() override;
+  bool closed() const override;
+
+  Result<int64_t> Read(int64_t nbytes, void* out) override;
+  Result<std::shared_ptr<Buffer>> Read(int64_t nbytes) override;
+  Result<int64_t> ReadAt(int64_t position, int64_t nbytes, void* out) override;
+  Result<std::shared_ptr<Buffer>> ReadAt(int64_t position, int64_t nbytes) override;
+  Result<util::string_view> Peek(int64_t nbytes) override;
+
+  Result<int64_t> GetSize() override;
+  Status Seek(int64_t position) override;
+  Result<int64_t> Tell() const override;
+};
+
+}  // namespace io
+}  // namespace arrow