device/hid/hid_service_linux.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "device/hid/hid_service_linux.h"
   6
   7 #include <linux/hidraw.h>
   8 #include <sys/ioctl.h>
   9 #include <stdint.h>
  10
  11 #include <string>
  12
  13 #include "base/bind.h"
  14 #include "base/files/file.h"
  15 #include "base/files/file_path.h"
  16 #include "base/logging.h"
  17 #include "base/stl_util.h"
  18 #include "base/strings/string_number_conversions.h"
  19 #include "base/strings/string_piece.h"
  20 #include "base/strings/string_split.h"
  21 #include "device/hid/hid_connection_linux.h"
  22 #include "device/hid/hid_device_info.h"
  23 #include "device/hid/hid_report_descriptor.h"
  24 #include "device/udev_linux/udev.h"
  25
  26 #if defined(OS_CHROMEOS)
  27 #include "base/sys_info.h"
  28 #include "chromeos/dbus/dbus_thread_manager.h"
  29 #include "chromeos/dbus/permission_broker_client.h"
  30 #endif  // defined(OS_CHROMEOS)
  31
  32 namespace device {
  33
  34 namespace {
  35
  36 const char kHidrawSubsystem[] = "hidraw";
  37 const char kHIDID[] = "HID_ID";
  38 const char kHIDName[] = "HID_NAME";
  39 const char kHIDUnique[] = "HID_UNIQ";
  40
  41 }  // namespace
  42
  43 HidServiceLinux::HidServiceLinux(
  44     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
  45     : ui_task_runner_(ui_task_runner),
  46       weak_factory_(this) {
  47   DeviceMonitorLinux* monitor = DeviceMonitorLinux::GetInstance();
  48   monitor->AddObserver(this);
  49   monitor->Enumerate(
  50       base::Bind(&HidServiceLinux::OnDeviceAdded, weak_factory_.GetWeakPtr()));
  51 }
  52
  53 scoped_refptr<HidConnection> HidServiceLinux::Connect(
  54     const HidDeviceId& device_id) {
  55   HidDeviceInfo device_info;
  56   if (!GetDeviceInfo(device_id, &device_info))
  57     return NULL;
  58
  59   ScopedUdevDevicePtr device =
  60       DeviceMonitorLinux::GetInstance()->GetDeviceFromPath(
  61           device_info.device_id);
  62
  63   if (device) {
  64     std::string dev_node = udev_device_get_devnode(device.get());
  65     return new HidConnectionLinux(device_info, dev_node);
  66   }
  67
  68   return NULL;
  69 }
  70
  71 HidServiceLinux::~HidServiceLinux() {
  72   if (DeviceMonitorLinux::HasInstance())
  73     DeviceMonitorLinux::GetInstance()->RemoveObserver(this);
  74 }
  75
  76 void HidServiceLinux::OnDeviceAdded(udev_device* device) {
  77   if (!device)
  78     return;
  79
  80   const char* device_path = udev_device_get_syspath(device);
  81   if (!device_path)
  82     return;
  83   const char* subsystem = udev_device_get_subsystem(device);
  84   if (!subsystem || strcmp(subsystem, kHidrawSubsystem) != 0)
  85     return;
  86
  87   scoped_ptr<HidDeviceInfo> device_info(new HidDeviceInfo);
  88   device_info->device_id = device_path;
  89
  90   uint32_t int_property = 0;
  91   const char* str_property = NULL;
  92
  93   udev_device *parent = udev_device_get_parent(device);
  94   if (!parent) {
  95     return;
  96   }
  97
  98   const char* hid_id = udev_device_get_property_value(parent, kHIDID);
  99   if (!hid_id)
 100     return;
 101
 102   std::vector<std::string> parts;
 103   base::SplitString(hid_id, ':', &parts);
 104   if (parts.size() != 3) {
 105     return;
 106   }
 107
 108   if (HexStringToUInt(base::StringPiece(parts[1]), &int_property)) {
 109     device_info->vendor_id = int_property;
 110   }
 111
 112   if (HexStringToUInt(base::StringPiece(parts[2]), &int_property)) {
 113     device_info->product_id = int_property;
 114   }
 115
 116   str_property = udev_device_get_property_value(parent, kHIDUnique);
 117   if (str_property != NULL)
 118     device_info->serial_number = str_property;
 119
 120   str_property = udev_device_get_property_value(parent, kHIDName);
 121   if (str_property != NULL)
 122     device_info->product_name = str_property;
 123
 124   const std::string dev_node = udev_device_get_devnode(device);
 125 #if defined(OS_CHROMEOS)
 126   // ChromeOS builds on non-ChromeOS machines (dev) should not attempt to
 127   // use permission broker.
 128   if (base::SysInfo::IsRunningOnChromeOS()) {
 129     chromeos::PermissionBrokerClient* client =
 130         chromeos::DBusThreadManager::Get()->GetPermissionBrokerClient();
 131     DCHECK(client) << "Could not get permission broker client.";
 132     if (!client) {
 133       return;
 134     }
 135     ui_task_runner_->PostTask(
 136         FROM_HERE,
 137         base::Bind(&chromeos::PermissionBrokerClient::RequestPathAccess,
 138                    base::Unretained(client),
 139                    dev_node,
 140                    -1,
 141                    base::Bind(&HidServiceLinux::OnRequestAccessComplete,
 142                               weak_factory_.GetWeakPtr(),
 143                               dev_node,
 144                               base::Passed(&device_info))));
 145   } else {
 146     OnRequestAccessComplete(dev_node, device_info.Pass(), true);
 147   }
 148 #else
 149   OnRequestAccessComplete(dev_node, device_info.Pass(), true);
 150 #endif  // defined(OS_CHROMEOS)
 151 }
 152
 153 void HidServiceLinux::OnDeviceRemoved(udev_device* device) {
 154   const char* device_path = udev_device_get_syspath(device);;
 155   if (device_path)
 156     RemoveDevice(device_path);
 157 }
 158
 159 void HidServiceLinux::OnRequestAccessComplete(
 160     const std::string& path,
 161     scoped_ptr<HidDeviceInfo> device_info,
 162     bool success) {
 163   const int flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
 164   base::File device_file(base::FilePath(path), flags);
 165   if (!device_file.IsValid()) {
 166     LOG(ERROR) << "Cannot open '" << path << "': "
 167         << base::File::ErrorToString(device_file.error_details());
 168     return;
 169   }
 170
 171   int desc_size = 0;
 172   int res = ioctl(device_file.GetPlatformFile(), HIDIOCGRDESCSIZE, &desc_size);
 173   if (res < 0) {
 174     PLOG(ERROR) << "Failed to get report descriptor size";
 175     device_file.Close();
 176     return;
 177   }
 178
 179   hidraw_report_descriptor rpt_desc;
 180   rpt_desc.size = desc_size;
 181
 182   res = ioctl(device_file.GetPlatformFile(), HIDIOCGRDESC, &rpt_desc);
 183   if (res < 0) {
 184     PLOG(ERROR) << "Failed to get report descriptor";
 185     device_file.Close();
 186     return;
 187   }
 188
 189   device_file.Close();
 190
 191   HidReportDescriptor report_descriptor(rpt_desc.value, rpt_desc.size);
 192   report_descriptor.GetDetails(&device_info->collections,
 193                                &device_info->has_report_id,
 194                                &device_info->max_input_report_size,
 195                                &device_info->max_output_report_size,
 196                                &device_info->max_feature_report_size);
 197
 198   AddDevice(*device_info);
 199 }
 200
 201 }  // namespace device