media/base/user_input_monitor_linux.cc

   1 // Copyright 2013 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 "media/base/user_input_monitor.h"
   6
   7 #include <sys/select.h>
   8 #include <unistd.h>
   9 #define XK_MISCELLANY
  10 #include <X11/keysymdef.h>
  11
  12 #include "base/basictypes.h"
  13 #include "base/bind.h"
  14 #include "base/callback.h"
  15 #include "base/compiler_specific.h"
  16 #include "base/location.h"
  17 #include "base/logging.h"
  18 #include "base/memory/weak_ptr.h"
  19 #include "base/message_loop/message_loop.h"
  20 #include "base/message_loop/message_pump_libevent.h"
  21 #include "base/single_thread_task_runner.h"
  22 #include "base/synchronization/lock.h"
  23 #include "media/base/keyboard_event_counter.h"
  24 #include "third_party/skia/include/core/SkPoint.h"
  25 #include "ui/events/keycodes/keyboard_code_conversion_x.h"
  26
  27 // These includes need to be later than dictated by the style guide due to
  28 // Xlib header pollution, specifically the min, max, and Status macros.
  29 #include <X11/XKBlib.h>
  30 #include <X11/Xlibint.h>
  31 #include <X11/extensions/record.h>
  32
  33 namespace media {
  34 namespace {
  35
  36 // This is the actual implementation of event monitoring. It's separated from
  37 // UserInputMonitorLinux since it needs to be deleted on the IO thread.
  38 class UserInputMonitorLinuxCore
  39     : public base::MessagePumpLibevent::Watcher,
  40       public base::SupportsWeakPtr<UserInputMonitorLinuxCore>,
  41       public base::MessageLoop::DestructionObserver {
  42  public:
  43   enum EventType {
  44     MOUSE_EVENT,
  45     KEYBOARD_EVENT
  46   };
  47
  48   explicit UserInputMonitorLinuxCore(
  49       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
  50       const scoped_refptr<UserInputMonitor::MouseListenerList>&
  51           mouse_listeners);
  52   virtual ~UserInputMonitorLinuxCore();
  53
  54   // DestructionObserver overrides.
  55   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
  56
  57   size_t GetKeyPressCount() const;
  58   void StartMonitor(EventType type);
  59   void StopMonitor(EventType type);
  60
  61  private:
  62   // base::MessagePumpLibevent::Watcher interface.
  63   virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
  64   virtual void OnFileCanWriteWithoutBlocking(int fd) OVERRIDE;
  65
  66   // Processes key and mouse events.
  67   void ProcessXEvent(xEvent* event);
  68   static void ProcessReply(XPointer self, XRecordInterceptData* data);
  69
  70   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
  71   scoped_refptr<ObserverListThreadSafe<UserInputMonitor::MouseEventListener> >
  72       mouse_listeners_;
  73
  74   //
  75   // The following members should only be accessed on the IO thread.
  76   //
  77   base::MessagePumpLibevent::FileDescriptorWatcher controller_;
  78   Display* x_control_display_;
  79   Display* x_record_display_;
  80   XRecordRange* x_record_range_[2];
  81   XRecordContext x_record_context_;
  82   KeyboardEventCounter counter_;
  83
  84   DISALLOW_COPY_AND_ASSIGN(UserInputMonitorLinuxCore);
  85 };
  86
  87 class UserInputMonitorLinux : public UserInputMonitor {
  88  public:
  89   explicit UserInputMonitorLinux(
  90       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner);
  91   virtual ~UserInputMonitorLinux();
  92
  93   // Public UserInputMonitor overrides.
  94   virtual size_t GetKeyPressCount() const OVERRIDE;
  95
  96  private:
  97   // Private UserInputMonitor overrides.
  98   virtual void StartKeyboardMonitoring() OVERRIDE;
  99   virtual void StopKeyboardMonitoring() OVERRIDE;
 100   virtual void StartMouseMonitoring() OVERRIDE;
 101   virtual void StopMouseMonitoring() OVERRIDE;
 102
 103   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 104   UserInputMonitorLinuxCore* core_;
 105
 106   DISALLOW_COPY_AND_ASSIGN(UserInputMonitorLinux);
 107 };
 108
 109 UserInputMonitorLinuxCore::UserInputMonitorLinuxCore(
 110     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
 111     const scoped_refptr<UserInputMonitor::MouseListenerList>& mouse_listeners)
 112     : io_task_runner_(io_task_runner),
 113       mouse_listeners_(mouse_listeners),
 114       x_control_display_(NULL),
 115       x_record_display_(NULL),
 116       x_record_context_(0) {
 117   x_record_range_[0] = NULL;
 118   x_record_range_[1] = NULL;
 119 }
 120
 121 UserInputMonitorLinuxCore::~UserInputMonitorLinuxCore() {
 122   DCHECK(!x_control_display_);
 123   DCHECK(!x_record_display_);
 124   DCHECK(!x_record_range_[0]);
 125   DCHECK(!x_record_range_[1]);
 126   DCHECK(!x_record_context_);
 127 }
 128
 129 void UserInputMonitorLinuxCore::WillDestroyCurrentMessageLoop() {
 130   DCHECK(io_task_runner_->BelongsToCurrentThread());
 131   StopMonitor(MOUSE_EVENT);
 132   StopMonitor(KEYBOARD_EVENT);
 133 }
 134
 135 size_t UserInputMonitorLinuxCore::GetKeyPressCount() const {
 136   return counter_.GetKeyPressCount();
 137 }
 138
 139 void UserInputMonitorLinuxCore::StartMonitor(EventType type) {
 140   DCHECK(io_task_runner_->BelongsToCurrentThread());
 141
 142   if (type == KEYBOARD_EVENT)
 143     counter_.Reset();
 144
 145   // TODO(jamiewalch): We should pass the display in. At that point, since
 146   // XRecord needs a private connection to the X Server for its data channel
 147   // and both channels are used from a separate thread, we'll need to duplicate
 148   // them with something like the following:
 149   //   XOpenDisplay(DisplayString(display));
 150   if (!x_control_display_)
 151     x_control_display_ = XOpenDisplay(NULL);
 152
 153   if (!x_record_display_)
 154     x_record_display_ = XOpenDisplay(NULL);
 155
 156   if (!x_control_display_ || !x_record_display_) {
 157     LOG(ERROR) << "Couldn't open X display";
 158     StopMonitor(type);
 159     return;
 160   }
 161
 162   int xr_opcode, xr_event, xr_error;
 163   if (!XQueryExtension(
 164            x_control_display_, "RECORD", &xr_opcode, &xr_event, &xr_error)) {
 165     LOG(ERROR) << "X Record extension not available.";
 166     StopMonitor(type);
 167     return;
 168   }
 169
 170   if (!x_record_range_[type])
 171     x_record_range_[type] = XRecordAllocRange();
 172
 173   if (!x_record_range_[type]) {
 174     LOG(ERROR) << "XRecordAllocRange failed.";
 175     StopMonitor(type);
 176     return;
 177   }
 178
 179   if (type == MOUSE_EVENT) {
 180     x_record_range_[type]->device_events.first = MotionNotify;
 181     x_record_range_[type]->device_events.last = MotionNotify;
 182   } else {
 183     DCHECK_EQ(KEYBOARD_EVENT, type);
 184     x_record_range_[type]->device_events.first = KeyPress;
 185     x_record_range_[type]->device_events.last = KeyRelease;
 186   }
 187
 188   if (x_record_context_) {
 189     XRecordDisableContext(x_control_display_, x_record_context_);
 190     XFlush(x_control_display_);
 191     XRecordFreeContext(x_record_display_, x_record_context_);
 192     x_record_context_ = 0;
 193   }
 194   XRecordRange** record_range_to_use =
 195       (x_record_range_[0] && x_record_range_[1]) ? x_record_range_
 196                                                  : &x_record_range_[type];
 197   int number_of_ranges = (x_record_range_[0] && x_record_range_[1]) ? 2 : 1;
 198
 199   XRecordClientSpec client_spec = XRecordAllClients;
 200   x_record_context_ = XRecordCreateContext(x_record_display_,
 201                                            0,
 202                                            &client_spec,
 203                                            1,
 204                                            record_range_to_use,
 205                                            number_of_ranges);
 206   if (!x_record_context_) {
 207     LOG(ERROR) << "XRecordCreateContext failed.";
 208     StopMonitor(type);
 209     return;
 210   }
 211
 212   if (!XRecordEnableContextAsync(x_record_display_,
 213                                  x_record_context_,
 214                                  &UserInputMonitorLinuxCore::ProcessReply,
 215                                  reinterpret_cast<XPointer>(this))) {
 216     LOG(ERROR) << "XRecordEnableContextAsync failed.";
 217     StopMonitor(type);
 218     return;
 219   }
 220
 221   if (!x_record_range_[0] || !x_record_range_[1]) {
 222     // Register OnFileCanReadWithoutBlocking() to be called every time there is
 223     // something to read from |x_record_display_|.
 224     base::MessageLoopForIO* message_loop = base::MessageLoopForIO::current();
 225     int result =
 226         message_loop->WatchFileDescriptor(ConnectionNumber(x_record_display_),
 227                                           true,
 228                                           base::MessageLoopForIO::WATCH_READ,
 229                                           &controller_,
 230                                           this);
 231     if (!result) {
 232       LOG(ERROR) << "Failed to create X record task.";
 233       StopMonitor(type);
 234       return;
 235     }
 236
 237     // Start observing message loop destruction if we start monitoring the first
 238     // event.
 239     base::MessageLoop::current()->AddDestructionObserver(this);
 240   }
 241
 242   // Fetch pending events if any.
 243   OnFileCanReadWithoutBlocking(ConnectionNumber(x_record_display_));
 244 }
 245
 246 void UserInputMonitorLinuxCore::StopMonitor(EventType type) {
 247   DCHECK(io_task_runner_->BelongsToCurrentThread());
 248
 249   if (x_record_range_[type]) {
 250     XFree(x_record_range_[type]);
 251     x_record_range_[type] = NULL;
 252   }
 253   if (x_record_range_[0] || x_record_range_[1])
 254     return;
 255
 256   // Context must be disabled via the control channel because we can't send
 257   // any X protocol traffic over the data channel while it's recording.
 258   if (x_record_context_) {
 259     XRecordDisableContext(x_control_display_, x_record_context_);
 260     XFlush(x_control_display_);
 261     XRecordFreeContext(x_record_display_, x_record_context_);
 262     x_record_context_ = 0;
 263
 264     controller_.StopWatchingFileDescriptor();
 265   }
 266   if (x_record_display_) {
 267     XCloseDisplay(x_record_display_);
 268     x_record_display_ = NULL;
 269   }
 270   if (x_control_display_) {
 271     XCloseDisplay(x_control_display_);
 272     x_control_display_ = NULL;
 273   }
 274   // Stop observing message loop destruction if no event is being monitored.
 275   base::MessageLoop::current()->RemoveDestructionObserver(this);
 276 }
 277
 278 void UserInputMonitorLinuxCore::OnFileCanReadWithoutBlocking(int fd) {
 279   DCHECK(io_task_runner_->BelongsToCurrentThread());
 280   XEvent event;
 281   // Fetch pending events if any.
 282   while (XPending(x_record_display_)) {
 283     XNextEvent(x_record_display_, &event);
 284   }
 285 }
 286
 287 void UserInputMonitorLinuxCore::OnFileCanWriteWithoutBlocking(int fd) {
 288   NOTREACHED();
 289 }
 290
 291 void UserInputMonitorLinuxCore::ProcessXEvent(xEvent* event) {
 292   DCHECK(io_task_runner_->BelongsToCurrentThread());
 293   if (event->u.u.type == MotionNotify) {
 294     SkIPoint position(SkIPoint::Make(event->u.keyButtonPointer.rootX,
 295                                      event->u.keyButtonPointer.rootY));
 296     mouse_listeners_->Notify(
 297         &UserInputMonitor::MouseEventListener::OnMouseMoved, position);
 298   } else {
 299     ui::EventType type;
 300     if (event->u.u.type == KeyPress) {
 301       type = ui::ET_KEY_PRESSED;
 302     } else if (event->u.u.type == KeyRelease) {
 303       type = ui::ET_KEY_RELEASED;
 304     } else {
 305       NOTREACHED();
 306       return;
 307     }
 308
 309     KeySym key_sym =
 310         XkbKeycodeToKeysym(x_control_display_, event->u.u.detail, 0, 0);
 311     ui::KeyboardCode key_code = ui::KeyboardCodeFromXKeysym(key_sym);
 312     counter_.OnKeyboardEvent(type, key_code);
 313   }
 314 }
 315
 316 // static
 317 void UserInputMonitorLinuxCore::ProcessReply(XPointer self,
 318                                              XRecordInterceptData* data) {
 319   if (data->category == XRecordFromServer) {
 320     xEvent* event = reinterpret_cast<xEvent*>(data->data);
 321     reinterpret_cast<UserInputMonitorLinuxCore*>(self)->ProcessXEvent(event);
 322   }
 323   XRecordFreeData(data);
 324 }
 325
 326 //
 327 // Implementation of UserInputMonitorLinux.
 328 //
 329
 330 UserInputMonitorLinux::UserInputMonitorLinux(
 331     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner)
 332     : io_task_runner_(io_task_runner),
 333       core_(new UserInputMonitorLinuxCore(io_task_runner, mouse_listeners())) {}
 334
 335 UserInputMonitorLinux::~UserInputMonitorLinux() {
 336   if (!io_task_runner_->DeleteSoon(FROM_HERE, core_))
 337     delete core_;
 338 }
 339
 340 size_t UserInputMonitorLinux::GetKeyPressCount() const {
 341   return core_->GetKeyPressCount();
 342 }
 343
 344 void UserInputMonitorLinux::StartKeyboardMonitoring() {
 345   io_task_runner_->PostTask(
 346       FROM_HERE,
 347       base::Bind(&UserInputMonitorLinuxCore::StartMonitor,
 348                  core_->AsWeakPtr(),
 349                  UserInputMonitorLinuxCore::KEYBOARD_EVENT));
 350 }
 351
 352 void UserInputMonitorLinux::StopKeyboardMonitoring() {
 353   io_task_runner_->PostTask(
 354       FROM_HERE,
 355       base::Bind(&UserInputMonitorLinuxCore::StopMonitor,
 356                  core_->AsWeakPtr(),
 357                  UserInputMonitorLinuxCore::KEYBOARD_EVENT));
 358 }
 359
 360 void UserInputMonitorLinux::StartMouseMonitoring() {
 361   io_task_runner_->PostTask(FROM_HERE,
 362                             base::Bind(&UserInputMonitorLinuxCore::StartMonitor,
 363                                        core_->AsWeakPtr(),
 364                                        UserInputMonitorLinuxCore::MOUSE_EVENT));
 365 }
 366
 367 void UserInputMonitorLinux::StopMouseMonitoring() {
 368   io_task_runner_->PostTask(FROM_HERE,
 369                             base::Bind(&UserInputMonitorLinuxCore::StopMonitor,
 370                                        core_->AsWeakPtr(),
 371                                        UserInputMonitorLinuxCore::MOUSE_EVENT));
 372 }
 373
 374 }  // namespace
 375
 376 scoped_ptr<UserInputMonitor> UserInputMonitor::Create(
 377     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
 378     const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner) {
 379   return scoped_ptr<UserInputMonitor>(
 380       new UserInputMonitorLinux(io_task_runner));
 381 }
 382
 383 }  // namespace media