text: // Copyright (c) 2010 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "content/browser/geolocation/wifi_data_provider_common_win.h"
  
  #include <assert.h>
  #include <stdint.h>
  
  #include "base/strings/utf_string_conversions.h"
  #include "content/browser/geolocation/wifi_data_provider_common.h"
  
  namespace content {
  
  bool ConvertToAccessPointData(const NDIS_WLAN_BSSID& data,
                                AccessPointData *access_point_data) {
    // Currently we get only MAC address, signal strength and SSID.
    // TODO(steveblock): Work out how to get age, channel and signal-to-noise.
    DCHECK(access_point_data);
    access_point_data->mac_address = MacAddressAsString16(data.MacAddress);
    access_point_data->radio_signal_strength = data.Rssi;
    // Note that _NDIS_802_11_SSID::Ssid::Ssid is not null-terminated.
    base::UTF8ToUTF16(reinterpret_cast<const char*>(data.Ssid.Ssid),
                      data.Ssid.SsidLength,
                      &access_point_data->ssid);
    return true;
  }
  
  int GetDataFromBssIdList(const NDIS_802_11_BSSID_LIST& bss_id_list,
                           int list_size,
                           WifiData::AccessPointDataSet* data) {
    // Walk through the BSS IDs.
    int found = 0;
    const uint8_t* iterator =
        reinterpret_cast<const uint8_t*>(&bss_id_list.Bssid[0]);
    const uint8_t* end_of_buffer =
        reinterpret_cast<const uint8_t*>(&bss_id_list) + list_size;
    for (int i = 0; i < static_cast<int>(bss_id_list.NumberOfItems); ++i) {
      const NDIS_WLAN_BSSID *bss_id =
          reinterpret_cast<const NDIS_WLAN_BSSID*>(iterator);
      // Check that the length of this BSS ID is reasonable.
      if (bss_id->Length < sizeof(NDIS_WLAN_BSSID) ||
          iterator + bss_id->Length > end_of_buffer) {
        break;
      }
      AccessPointData access_point_data;
      if (ConvertToAccessPointData(*bss_id, &access_point_data)) {
        data->insert(access_point_data);
        ++found;
      }
      // Move to the next BSS ID.
      iterator += bss_id->Length;
    }
    return found;
  }
  
  }  // namespace content
  