modules/desktop_capture/linux/x_window_property.cc

/*
 *  Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "modules/desktop_capture/linux/x_window_property.h"

namespace webrtc {

XWindowPropertyBase::XWindowPropertyBase(Display* display,
                                         Window window,
                                         Atom property,
                                         int expected_size) {
  const int kBitsPerByte = 8;
  Atom actual_type;
  int actual_format;
  unsigned long bytes_after;  // NOLINT: type required by XGetWindowProperty
  int status = XGetWindowProperty(display, window, property, 0L, ~0L, False,
                                  AnyPropertyType, &actual_type, &actual_format,
                                  &size_, &bytes_after, &data_);
  if (status != Success) {
    data_ = nullptr;
    return;
  }
  if ((expected_size * kBitsPerByte) != actual_format) {
    size_ = 0;
    return;
  }

  is_valid_ = true;
}

XWindowPropertyBase::~XWindowPropertyBase() {
  if (data_)
    XFree(data_);
}

}  // namespace webrtc