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diff --git a/third_party/libwebrtc/test/fuzzers/fuzz_data_helper.h b/third_party/libwebrtc/test/fuzzers/fuzz_data_helper.h
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+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef TEST_FUZZERS_FUZZ_DATA_HELPER_H_
+#define TEST_FUZZERS_FUZZ_DATA_HELPER_H_
+
+#include <limits>
+
+#include "api/array_view.h"
+#include "modules/rtp_rtcp/source/byte_io.h"
+
+namespace webrtc {
+namespace test {
+
+// Helper class to take care of the fuzzer input, read from it, and keep track
+// of when the end of the data has been reached.
+class FuzzDataHelper {
+ public:
+  explicit FuzzDataHelper(rtc::ArrayView<const uint8_t> data);
+
+  // Returns true if n bytes can be read.
+  bool CanReadBytes(size_t n) const { return data_ix_ + n <= data_.size(); }
+
+  // Reads and returns data of type T.
+  template <typename T>
+  T Read() {
+    RTC_CHECK(CanReadBytes(sizeof(T)));
+    T x = ByteReader<T>::ReadLittleEndian(&data_[data_ix_]);
+    data_ix_ += sizeof(T);
+    return x;
+  }
+
+  // Reads and returns data of type T. Returns default_value if not enough
+  // fuzzer input remains to read a T.
+  template <typename T>
+  T ReadOrDefaultValue(T default_value) {
+    if (!CanReadBytes(sizeof(T))) {
+      return default_value;
+    }
+    return Read<T>();
+  }
+
+  // Like ReadOrDefaultValue, but replaces the value 0 with default_value.
+  template <typename T>
+  T ReadOrDefaultValueNotZero(T default_value) {
+    static_assert(std::is_integral<T>::value, "");
+    T x = ReadOrDefaultValue(default_value);
+    return x == 0 ? default_value : x;
+  }
+
+  // Returns one of the elements from the provided input array. The selection
+  // is based on the fuzzer input data. If not enough fuzzer data is available,
+  // the method will return the first element in the input array. The reason for
+  // not flagging this as an error is to allow the method to be called from
+  // class constructors, and in constructors we typically do not handle
+  // errors. The code will work anyway, and the fuzzer will likely see that
+  // providing more data will actually make this method return something else.
+  template <typename T, size_t N>
+  T SelectOneOf(const T (&select_from)[N]) {
+    static_assert(N <= std::numeric_limits<uint8_t>::max(), "");
+    // Read an index between 0 and select_from.size() - 1 from the fuzzer data.
+    uint8_t index = ReadOrDefaultValue<uint8_t>(0) % N;
+    return select_from[index];
+  }
+
+  rtc::ArrayView<const uint8_t> ReadByteArray(size_t bytes) {
+    if (!CanReadBytes(bytes)) {
+      return rtc::ArrayView<const uint8_t>(nullptr, 0);
+    }
+    const size_t index_to_return = data_ix_;
+    data_ix_ += bytes;
+    return data_.subview(index_to_return, bytes);
+  }
+
+  // If sizeof(T) > BytesLeft then the remaining bytes will be used and the rest
+  // of the object will be zero initialized.
+  template <typename T>
+  void CopyTo(T* object) {
+    memset(object, 0, sizeof(T));
+
+    size_t bytes_to_copy = std::min(BytesLeft(), sizeof(T));
+    memcpy(object, data_.data() + data_ix_, bytes_to_copy);
+    data_ix_ += bytes_to_copy;
+  }
+
+  size_t BytesRead() const { return data_ix_; }
+
+  size_t BytesLeft() const { return data_.size() - data_ix_; }
+
+ private:
+  rtc::ArrayView<const uint8_t> data_;
+  size_t data_ix_ = 0;
+};
+
+}  // namespace test
+}  // namespace webrtc
+
+#endif  // TEST_FUZZERS_FUZZ_DATA_HELPER_H_