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// libFuzzer harness for fuzzing snappy's decompression code.

#include <stddef.h>

#include <stdint.h>

#include <cassert>

#include <string>

#include "snappy.h"

// Entry point for LibFuzzer.

extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {

  std::string input(reinterpret_cast<const char*>(data), size);

  // Avoid self-crafted decompression bombs.

  size_t uncompressed_size;

  constexpr size_t kMaxUncompressedSize = 1 << 20;

  bool get_uncompressed_length_succeeded = snappy::GetUncompressedLength(

      input.data(), input.size(), &uncompressed_size);

  if (!get_uncompressed_length_succeeded ||

      (uncompressed_size > kMaxUncompressedSize)) {

    return 0;

  }

  std::string uncompressed;

  // The return value of snappy::Uncompress() is ignored because decompression

  // will fail on invalid inputs.

  snappy::Uncompress(input.data(), input.size(), &uncompressed);

  return 0;

}