bit_reader_fuzzertest.cc 1.6 KB

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  1. // Copyright 2016 The Chromium Authors. All rights reserved.
  2. // Use of this source code is governed by a BSD-style license that can be
  3. // found in the LICENSE file.
  4. #include <stddef.h>
  5. #include <stdint.h>
  6. #include "base/containers/buffer_iterator.h"
  7. #include "base/containers/span.h"
  8. #include "base/numerics/safe_conversions.h"
  9. #include "media/base/bit_reader.h"
  10. #include "media/base/test_random.h"
  11. // Entry point for LibFuzzer.
  12. extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
  13. base::BufferIterator<const uint8_t> iterator(data, size);
  14. const uint32_t* random_seed = iterator.Object<uint32_t>();
  15. if (!random_seed)
  16. return 0;
  17. // Need a simple random number generator to generate the number of bits to
  18. // read/skip in a reproducible way (given the same |data|).
  19. media::TestRandom rnd(*random_seed);
  20. base::span<const uint8_t> remaining =
  21. iterator.Span<uint8_t>(iterator.total_size() - iterator.position());
  22. media::BitReader reader(remaining.data(),
  23. base::checked_cast<int>(remaining.size()));
  24. // Read and skip through the data in |reader|.
  25. while (reader.bits_available() > 0) {
  26. if (rnd.Rand() & 1) {
  27. // Read up to 64 bits. This may fail if there is not enough bits
  28. // remaining, but it doesn't matter (testing for failures is also good).
  29. uint64_t value;
  30. if (!reader.ReadBits(rnd.Rand() % 64 + 1, &value))
  31. break;
  32. } else {
  33. // Skip up to 128 bits. As above, this may fail.
  34. if (!reader.SkipBits(rnd.Rand() % 128 + 1))
  35. break;
  36. }
  37. }
  38. return 0;
  39. }