Function ToGuard

tensorflow/cc/framework/cc_op_gen.cc:86–100

Converts: cc/ops/gen_foo_ops.h to: CC_OPS_GEN_FOO_OPS_H_

// to:
//   CC_OPS_GEN_FOO_OPS_H_
string ToGuard(const string& path) {
  string guard;
  guard.reserve(path.size() + 1);  // + 1 -> trailing _
  for (const char c : path) {
    if (c >= 'A' && c <= 'Z') {
      guard += c;
    } else if (c >= 'a' && c <= 'z') {
      guard += c + 'A' - 'a';
    } else {
      guard += '_';
    }
  }
  guard += '_';
  return guard;
}

// Converts: some_name_xyz
// to: Some Name Xyz