blob: 37e2dc4199ac03e71e3a8e761f5a2ae91d456f37 [file] [log] [blame]
// Copyright 2014 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 "device/serial/serial_device_enumerator_win.h"
#include <devguid.h>
#include <setupapi.h>
#include <stdint.h>
#include <windows.h>
#include <memory>
#include "base/metrics/sparse_histogram.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "base/win/registry.h"
#include "third_party/re2/src/re2/re2.h"
namespace device {
namespace {
// Searches the specified device info for a property with the specified key,
// assigns the result to value, and returns whether the operation was
// successful.
bool GetProperty(HDEVINFO dev_info,
SP_DEVINFO_DATA dev_info_data,
const int key,
std::string* value) {
// We don't know how much space the property's value will take up, so we call
// the property retrieval function once to fetch the size of the required
// value buffer, then again once we've allocated a sufficiently large buffer.
DWORD buffer_size = 0;
SetupDiGetDeviceRegistryProperty(dev_info, &dev_info_data, key, nullptr,
nullptr, buffer_size, &buffer_size);
return false;
std::unique_ptr<wchar_t[]> buffer(new wchar_t[buffer_size]);
if (!SetupDiGetDeviceRegistryProperty(dev_info, &dev_info_data, key, nullptr,
buffer_size, nullptr))
return false;
*value = base::WideToUTF8(buffer.get());
return true;
// Searches for the COM port in the device's friendly name, assigns its value to
// com_port, and returns whether the operation was successful.
bool GetCOMPort(const std::string friendly_name, std::string* com_port) {
return RE2::PartialMatch(friendly_name, ".* \\((COM[0-9]+)\\)", com_port);
// Searches for the display name in the device's friendly name, assigns its
// value to display_name, and returns whether the operation was successful.
bool GetDisplayName(const std::string friendly_name,
std::string* display_name) {
return RE2::PartialMatch(friendly_name, "(.*) \\(COM[0-9]+\\)", display_name);
// Searches for the vendor ID in the device's hardware ID, assigns its value to
// vendor_id, and returns whether the operation was successful.
bool GetVendorID(const std::string hardware_id, uint32_t* vendor_id) {
std::string vendor_id_str;
return RE2::PartialMatch(hardware_id, "VID_([0-9a-fA-F]+)", &vendor_id_str) &&
base::HexStringToUInt(vendor_id_str, vendor_id);
// Searches for the product ID in the device's product ID, assigns its value to
// product_id, and returns whether the operation was successful.
bool GetProductID(const std::string hardware_id, uint32_t* product_id) {
std::string product_id_str;
return RE2::PartialMatch(hardware_id, "PID_([0-9a-fA-F]+)",
&product_id_str) &&
base::HexStringToUInt(product_id_str, product_id);
// Returns value clamped to the range of [min, max].
int Clamp(int value, int min, int max) {
return std::min(std::max(value, min), max);
// Returns an array of devices as retrieved through the new method of
// enumerating serial devices (SetupDi). This new method gives more information
// about the devices than the old method.
mojo::Array<serial::DeviceInfoPtr> GetDevicesNew() {
mojo::Array<serial::DeviceInfoPtr> devices;
// Make a device interface query to find all serial devices.
HDEVINFO dev_info =
if (dev_info == INVALID_HANDLE_VALUE)
return devices;
SP_DEVINFO_DATA dev_info_data;
dev_info_data.cbSize = sizeof(SP_DEVINFO_DATA);
for (DWORD i = 0; SetupDiEnumDeviceInfo(dev_info, i, &dev_info_data); i++) {
std::string friendly_name, com_port;
if (!GetProperty(dev_info, dev_info_data, SPDRP_FRIENDLYNAME,
&friendly_name) ||
!GetCOMPort(friendly_name, &com_port))
// In Windows, the COM port is the path used to uniquely identify the
// serial device. If the COM can't be found, ignore the device.
serial::DeviceInfoPtr info(serial::DeviceInfo::New());
info->path = com_port;
std::string display_name;
if (GetDisplayName(friendly_name, &display_name))
info->display_name = display_name;
std::string hardware_id;
if (GetProperty(dev_info, dev_info_data, SPDRP_HARDWAREID, &hardware_id)) {
uint32_t vendor_id, product_id;
if (GetVendorID(hardware_id, &vendor_id)) {
info->has_vendor_id = true;
info->vendor_id = vendor_id;
if (GetProductID(hardware_id, &product_id)) {
info->has_product_id = true;
info->product_id = product_id;
return devices;
// Returns an array of devices as retrieved through the old method of
// enumerating serial devices (searching the registry). This old method gives
// less information about the devices than the new method.
mojo::Array<serial::DeviceInfoPtr> GetDevicesOld() {
base::win::RegistryValueIterator iter_key(
mojo::Array<serial::DeviceInfoPtr> devices;
for (; iter_key.Valid(); ++iter_key) {
serial::DeviceInfoPtr info(serial::DeviceInfo::New());
info->path = base::UTF16ToASCII(iter_key.Value());
return devices;
} // namespace
// static
std::unique_ptr<SerialDeviceEnumerator> SerialDeviceEnumerator::Create() {
return std::unique_ptr<SerialDeviceEnumerator>(
new SerialDeviceEnumeratorWin());
SerialDeviceEnumeratorWin::SerialDeviceEnumeratorWin() {}
SerialDeviceEnumeratorWin::~SerialDeviceEnumeratorWin() {}
mojo::Array<serial::DeviceInfoPtr> SerialDeviceEnumeratorWin::GetDevices() {
mojo::Array<serial::DeviceInfoPtr> newDevices = GetDevicesNew();
mojo::Array<serial::DeviceInfoPtr> oldDevices = GetDevicesOld();
Clamp((int)newDevices.size() - (int)oldDevices.size(), -10, 10));
// Add devices found from both the new and old methods of enumeration. If a
// device is found using both the new and the old enumeration method, then we
// take the device from the new enumeration method because it's able to
// collect more information. We do this by inserting the new devices first,
// because insertions are ignored if the key already exists.
mojo::Map<mojo::String, serial::DeviceInfoPtr> deviceMap;
for (unsigned long i = 0; i < newDevices.size(); i++) {
deviceMap.insert(newDevices[i]->path, newDevices[i].Clone());
for (unsigned long i = 0; i < oldDevices.size(); i++) {
deviceMap.insert(oldDevices[i]->path, oldDevices[i].Clone());
mojo::Array<mojo::String> paths;
mojo::Array<serial::DeviceInfoPtr> devices;
deviceMap.DecomposeMapTo(&paths, &devices);
return devices;
} // namespace device