// Ceres Solver - A fast non-linear least squares minimizer

// Copyright 2015 Google Inc. All rights reserved.

// http://ceres-solver.org/

//

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are met:

//

// * Redistributions of source code must retain the above copyright notice,

//   this list of conditions and the following disclaimer.

// * Redistributions in binary form must reproduce the above copyright notice,

//   this list of conditions and the following disclaimer in the documentation

//   and/or other materials provided with the distribution.

// * Neither the name of Google Inc. nor the names of its contributors may be

//   used to endorse or promote products derived from this software without

//   specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

// POSSIBILITY OF SUCH DAMAGE.

//

// Author: keir@google.com (Keir Mierle)

//

// Really simple file IO.

#include "ceres/file.h"

#include <cstdio>

#include "glog/logging.h"

namespace ceres {

namespace internal {

using std::string;

void WriteStringToFileOrDie(const string &data, const string &filename) {

  FILE* file_descriptor = fopen(filename.c_str(), "wb");

  if (!file_descriptor) {

    LOG(FATAL) << "Couldn't write to file: " << filename;

  }

  fwrite(data.c_str(), 1, data.size(), file_descriptor);

  fclose(file_descriptor);

}

void ReadFileToStringOrDie(const string &filename, string *data) {

  FILE* file_descriptor = fopen(filename.c_str(), "r");

  if (!file_descriptor) {

    LOG(FATAL) << "Couldn't read file: " << filename;

  }

  // Resize the input buffer appropriately.

  fseek(file_descriptor, 0L, SEEK_END);

  int num_bytes = ftell(file_descriptor);

  data->resize(num_bytes);

  // Read the data.

  fseek(file_descriptor, 0L, SEEK_SET);

  int num_read = fread(&((*data)[0]),

                       sizeof((*data)[0]),

                       num_bytes,

                       file_descriptor);

  if (num_read != num_bytes) {

    LOG(FATAL) << "Couldn't read all of " << filename

               << "expected bytes: " << num_bytes * sizeof((*data)[0])

               << "actual bytes: " << num_read;

  }

  fclose(file_descriptor);

}

string JoinPath(const string& dirname, const string& basename) {

#ifdef _WIN32

    static const char separator = '\\';

#else

    static const char separator = '/';

#endif  // _WIN32

  if ((!basename.empty() && basename[0] == separator) || dirname.empty()) {

    return basename;

  } else if (dirname[dirname.size() - 1] == separator) {

    return dirname + basename;

  } else {

    return dirname + string(&separator, 1) + basename;

  }

}

}  // namespace internal

}  // namespace ceres