// Copyright 2019 Google LLC

//

// Licensed 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.

#include <cstddef>

#include <cstdint>

#include <cstdlib>

#include <string>

#include "Eigen/Core"

using ::Eigen::Matrix;

using ::Eigen::Dynamic;

using ::Eigen::Lower;

using ::Eigen::Upper;

int ConsumeNextInt(const uint8_t** data, size_t* size) {

  if (*size < sizeof(int)) {

    return 0;

  }

  int result;

  memcpy(&result, *data, sizeof(int));

  *size -= sizeof(int);

  *data += sizeof(int);

  return result;

}

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

  const size_t rows = static_cast<size_t>(ConsumeNextInt(&data, &size));

  const size_t columns = static_cast<size_t>(ConsumeNextInt(&data, &size));

  if (rows == 0 || columns == 0) {

    return 0;

  }

  if (rows > 1024 || columns > 1024) {

    return 0;

  }

  // We can do this same fuzz test with other templated types. Here, we just use

  // an int.

  Matrix<int, Dynamic, 1> vec(rows);

  for (size_t i = 0; i < rows; ++i) {

    vec(i) = ConsumeNextInt(&data, &size);

  }

  Matrix<int, Dynamic, Dynamic> matrix(rows, columns);

  for (int i = 0; i < rows; ++i) {

    for (int j = 0; j < columns; ++j) {

      matrix(i, j) = ConsumeNextInt(&data, &size);

    }

  }

  matrix.template triangularView<Lower>().solve(vec);

  matrix.template triangularView<Upper>().solve(vec);

  matrix.conjugate().template triangularView<Lower>().solve(vec);

  matrix.conjugate().template triangularView<Upper>().solve(vec);

  matrix.transpose().template triangularView<Lower>().solve(vec);

  matrix.transpose().template triangularView<Upper>().solve(vec);

  return 0;

}