src/content/browser/web_contents/web_contents_drag_win.cc

   1 // Copyright (c) 2012 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 "content/browser/web_contents/web_contents_drag_win.h"
   6
   7 #include <windows.h>
   8
   9 #include <string>
  10
  11 #include "base/bind.h"
  12 #include "base/file_util.h"
  13 #include "base/files/file_path.h"
  14 #include "base/message_loop/message_loop.h"
  15 #include "base/pickle.h"
  16 #include "base/strings/utf_string_conversions.h"
  17 #include "base/threading/platform_thread.h"
  18 #include "base/threading/thread.h"
  19 #include "content/browser/download/drag_download_file.h"
  20 #include "content/browser/download/drag_download_util.h"
  21 #include "content/browser/web_contents/web_drag_dest_win.h"
  22 #include "content/browser/web_contents/web_drag_source_win.h"
  23 #include "content/browser/web_contents/web_drag_utils_win.h"
  24 #include "content/public/browser/browser_thread.h"
  25 #include "content/public/browser/content_browser_client.h"
  26 #include "content/public/browser/web_contents.h"
  27 #include "content/public/browser/web_contents_view.h"
  28 #include "content/public/browser/web_drag_dest_delegate.h"
  29 #include "content/public/common/drop_data.h"
  30 #include "net/base/net_util.h"
  31 #include "third_party/skia/include/core/SkBitmap.h"
  32 #include "ui/base/clipboard/clipboard.h"
  33 #include "ui/base/clipboard/custom_data_helper.h"
  34 #include "ui/base/dragdrop/drag_utils.h"
  35 #include "ui/base/layout.h"
  36 #include "ui/base/win/scoped_ole_initializer.h"
  37 #include "ui/gfx/image/image_skia.h"
  38 #include "ui/gfx/screen.h"
  39 #include "ui/gfx/size.h"
  40
  41 using WebKit::WebDragOperationsMask;
  42 using WebKit::WebDragOperationCopy;
  43 using WebKit::WebDragOperationLink;
  44 using WebKit::WebDragOperationMove;
  45
  46 namespace content {
  47 namespace {
  48
  49 bool run_do_drag_drop = true;
  50
  51 HHOOK msg_hook = NULL;
  52 DWORD drag_out_thread_id = 0;
  53 bool mouse_up_received = false;
  54
  55 LRESULT CALLBACK MsgFilterProc(int code, WPARAM wparam, LPARAM lparam) {
  56   if (code == base::MessagePumpForUI::kMessageFilterCode &&
  57       !mouse_up_received) {
  58     MSG* msg = reinterpret_cast<MSG*>(lparam);
  59     // We do not care about WM_SYSKEYDOWN and WM_SYSKEYUP because when ALT key
  60     // is pressed down on drag-and-drop, it means to create a link.
  61     if (msg->message == WM_MOUSEMOVE || msg->message == WM_LBUTTONUP ||
  62         msg->message == WM_KEYDOWN || msg->message == WM_KEYUP) {
  63       // Forward the message from the UI thread to the drag-and-drop thread.
  64       PostThreadMessage(drag_out_thread_id,
  65                         msg->message,
  66                         msg->wParam,
  67                         msg->lParam);
  68
  69       // If the left button is up, we do not need to forward the message any
  70       // more.
  71       if (msg->message == WM_LBUTTONUP || !(GetKeyState(VK_LBUTTON) & 0x8000))
  72         mouse_up_received = true;
  73
  74       return TRUE;
  75     }
  76   }
  77   return CallNextHookEx(msg_hook, code, wparam, lparam);
  78 }
  79
  80 void EnableBackgroundDraggingSupport(DWORD thread_id) {
  81   // Install a hook procedure to monitor the messages so that we can forward
  82   // the appropriate ones to the background thread.
  83   drag_out_thread_id = thread_id;
  84   mouse_up_received = false;
  85   DCHECK(!msg_hook);
  86   msg_hook = SetWindowsHookEx(WH_MSGFILTER,
  87                               MsgFilterProc,
  88                               NULL,
  89                               GetCurrentThreadId());
  90
  91   // Attach the input state of the background thread to the UI thread so that
  92   // SetCursor can work from the background thread.
  93   AttachThreadInput(drag_out_thread_id, GetCurrentThreadId(), TRUE);
  94 }
  95
  96 void DisableBackgroundDraggingSupport() {
  97   DCHECK(msg_hook);
  98   AttachThreadInput(drag_out_thread_id, GetCurrentThreadId(), FALSE);
  99   UnhookWindowsHookEx(msg_hook);
 100   msg_hook = NULL;
 101 }
 102
 103 bool IsBackgroundDraggingSupportEnabled() {
 104   return msg_hook != NULL;
 105 }
 106
 107 }  // namespace
 108
 109 class DragDropThread : public base::Thread {
 110  public:
 111   explicit DragDropThread(WebContentsDragWin* drag_handler)
 112        : Thread("Chrome_DragDropThread"),
 113          drag_handler_(drag_handler) {
 114   }
 115
 116   virtual ~DragDropThread() {
 117     Stop();
 118   }
 119
 120  protected:
 121   // base::Thread implementations:
 122   virtual void Init() {
 123     ole_initializer_.reset(new ui::ScopedOleInitializer());
 124   }
 125
 126   virtual void CleanUp() {
 127     ole_initializer_.reset();
 128   }
 129
 130  private:
 131   scoped_ptr<ui::ScopedOleInitializer> ole_initializer_;
 132
 133   // Hold a reference count to WebContentsDragWin to make sure that it is always
 134   // alive in the thread lifetime.
 135   scoped_refptr<WebContentsDragWin> drag_handler_;
 136
 137   DISALLOW_COPY_AND_ASSIGN(DragDropThread);
 138 };
 139
 140 WebContentsDragWin::WebContentsDragWin(
 141     gfx::NativeWindow source_window,
 142     WebContents* web_contents,
 143     WebDragDest* drag_dest,
 144     const base::Callback<void()>& drag_end_callback)
 145     : drag_drop_thread_id_(0),
 146       source_window_(source_window),
 147       web_contents_(web_contents),
 148       drag_dest_(drag_dest),
 149       drag_ended_(false),
 150       drag_end_callback_(drag_end_callback) {
 151 }
 152
 153 WebContentsDragWin::~WebContentsDragWin() {
 154   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 155   DCHECK(!drag_drop_thread_.get());
 156 }
 157
 158 void WebContentsDragWin::StartDragging(const DropData& drop_data,
 159                                        WebDragOperationsMask ops,
 160                                        const gfx::ImageSkia& image,
 161                                        const gfx::Vector2d& image_offset) {
 162   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 163
 164   drag_source_ = new WebDragSource(source_window_, web_contents_);
 165
 166   const GURL& page_url = web_contents_->GetLastCommittedURL();
 167   const std::string& page_encoding = web_contents_->GetEncoding();
 168
 169   // If it is not drag-out, do the drag-and-drop in the current UI thread.
 170   if (drop_data.download_metadata.empty()) {
 171     if (DoDragging(drop_data, ops, page_url, page_encoding,
 172                    image, image_offset))
 173       EndDragging();
 174     return;
 175   }
 176
 177   // Start a background thread to do the drag-and-drop.
 178   DCHECK(!drag_drop_thread_.get());
 179   drag_drop_thread_.reset(new DragDropThread(this));
 180   base::Thread::Options options;
 181   options.message_loop_type = base::MessageLoop::TYPE_UI;
 182   if (drag_drop_thread_->StartWithOptions(options)) {
 183     drag_drop_thread_->message_loop()->PostTask(
 184         FROM_HERE,
 185         base::Bind(&WebContentsDragWin::StartBackgroundDragging, this,
 186                    drop_data, ops, page_url, page_encoding,
 187                    image, image_offset));
 188   }
 189
 190   EnableBackgroundDraggingSupport(drag_drop_thread_->thread_id());
 191 }
 192
 193 void WebContentsDragWin::StartBackgroundDragging(
 194     const DropData& drop_data,
 195     WebDragOperationsMask ops,
 196     const GURL& page_url,
 197     const std::string& page_encoding,
 198     const gfx::ImageSkia& image,
 199     const gfx::Vector2d& image_offset) {
 200   drag_drop_thread_id_ = base::PlatformThread::CurrentId();
 201
 202   if (DoDragging(drop_data, ops, page_url, page_encoding,
 203                  image, image_offset)) {
 204     BrowserThread::PostTask(
 205         BrowserThread::UI,
 206         FROM_HERE,
 207         base::Bind(&WebContentsDragWin::EndDragging, this));
 208   } else {
 209     // When DoDragging returns false, the contents view window is gone and thus
 210     // WebContentsViewWin instance becomes invalid though WebContentsDragWin
 211     // instance is still alive because the task holds a reference count to it.
 212     // We should not do more than the following cleanup items:
 213     // 1) Remove the background dragging support. This is safe since it does not
 214     //    access the instance at all.
 215     // 2) Stop the background thread. This is done in OnDataObjectDisposed.
 216     //    Only drag_drop_thread_ member is accessed.
 217     BrowserThread::PostTask(
 218         BrowserThread::UI,
 219         FROM_HERE,
 220         base::Bind(&DisableBackgroundDraggingSupport));
 221   }
 222 }
 223
 224 void WebContentsDragWin::PrepareDragForDownload(
 225     const DropData& drop_data,
 226     ui::OSExchangeData* data,
 227     const GURL& page_url,
 228     const std::string& page_encoding) {
 229   // Parse the download metadata.
 230   string16 mime_type;
 231   base::FilePath file_name;
 232   GURL download_url;
 233   if (!ParseDownloadMetadata(drop_data.download_metadata,
 234                              &mime_type,
 235                              &file_name,
 236                              &download_url))
 237     return;
 238
 239   // Generate the file name based on both mime type and proposed file name.
 240   std::string default_name =
 241       GetContentClient()->browser()->GetDefaultDownloadName();
 242   base::FilePath generated_download_file_name =
 243       net::GenerateFileName(download_url,
 244                             std::string(),
 245                             std::string(),
 246                             UTF16ToUTF8(file_name.value()),
 247                             UTF16ToUTF8(mime_type),
 248                             default_name);
 249   base::FilePath temp_dir_path;
 250   if (!file_util::CreateNewTempDirectory(
 251           FILE_PATH_LITERAL("chrome_drag"), &temp_dir_path))
 252     return;
 253   base::FilePath download_path =
 254       temp_dir_path.Append(generated_download_file_name);
 255
 256   // We cannot know when the target application will be done using the temporary
 257   // file, so schedule it to be deleted after rebooting.
 258   base::DeleteFileAfterReboot(download_path);
 259   base::DeleteFileAfterReboot(temp_dir_path);
 260
 261   // Provide the data as file (CF_HDROP). A temporary download file with the
 262   // Zone.Identifier ADS (Alternate Data Stream) attached will be created.
 263   scoped_refptr<DragDownloadFile> download_file =
 264       new DragDownloadFile(
 265           download_path,
 266           scoped_ptr<net::FileStream>(),
 267           download_url,
 268           Referrer(page_url, drop_data.referrer_policy),
 269           page_encoding,
 270           web_contents_);
 271   ui::OSExchangeData::DownloadFileInfo file_download(base::FilePath(),
 272                                                      download_file.get());
 273   data->SetDownloadFileInfo(file_download);
 274
 275   // Enable asynchronous operation.
 276   ui::OSExchangeDataProviderWin::GetIAsyncOperation(*data)->SetAsyncMode(TRUE);
 277 }
 278
 279 void WebContentsDragWin::PrepareDragForFileContents(
 280     const DropData& drop_data, ui::OSExchangeData* data) {
 281   static const int kMaxFilenameLength = 255;  // FAT and NTFS
 282   base::FilePath file_name(drop_data.file_description_filename);
 283
 284   // Images without ALT text will only have a file extension so we need to
 285   // synthesize one from the provided extension and URL.
 286   if (file_name.BaseName().RemoveExtension().empty()) {
 287     const string16 extension = file_name.Extension();
 288     // Retrieve the name from the URL.
 289     file_name = base::FilePath(
 290         net::GetSuggestedFilename(drop_data.url, "", "", "", "", ""));
 291     if (file_name.value().size() + extension.size() > kMaxFilenameLength) {
 292       file_name = base::FilePath(file_name.value().substr(
 293           0, kMaxFilenameLength - extension.size()));
 294     }
 295     file_name = file_name.ReplaceExtension(extension);
 296   }
 297   data->SetFileContents(file_name, drop_data.file_contents);
 298 }
 299
 300 void WebContentsDragWin::PrepareDragForUrl(const DropData& drop_data,
 301                                            ui::OSExchangeData* data) {
 302   if (drag_dest_->delegate() &&
 303       drag_dest_->delegate()->AddDragData(drop_data, data)) {
 304     return;
 305   }
 306
 307   data->SetURL(drop_data.url, drop_data.url_title);
 308 }
 309
 310 bool WebContentsDragWin::DoDragging(const DropData& drop_data,
 311                                     WebDragOperationsMask ops,
 312                                     const GURL& page_url,
 313                                     const std::string& page_encoding,
 314                                     const gfx::ImageSkia& image,
 315                                     const gfx::Vector2d& image_offset) {
 316   ui::OSExchangeData data;
 317
 318   if (!drop_data.download_metadata.empty()) {
 319     PrepareDragForDownload(drop_data, &data, page_url, page_encoding);
 320
 321     // Set the observer.
 322     ui::OSExchangeDataProviderWin::GetDataObjectImpl(data)->set_observer(this);
 323   }
 324
 325   // We set the file contents before the URL because the URL also sets file
 326   // contents (to a .URL shortcut).  We want to prefer file content data over
 327   // a shortcut so we add it first.
 328   if (!drop_data.file_contents.empty())
 329     PrepareDragForFileContents(drop_data, &data);
 330   if (!drop_data.html.string().empty())
 331     data.SetHtml(drop_data.html.string(), drop_data.html_base_url);
 332   // We set the text contents before the URL because the URL also sets text
 333   // content.
 334   if (!drop_data.text.string().empty())
 335     data.SetString(drop_data.text.string());
 336   if (drop_data.url.is_valid())
 337     PrepareDragForUrl(drop_data, &data);
 338   if (!drop_data.custom_data.empty()) {
 339     Pickle pickle;
 340     ui::WriteCustomDataToPickle(drop_data.custom_data, &pickle);
 341     data.SetPickledData(ui::Clipboard::GetWebCustomDataFormatType(), pickle);
 342   }
 343
 344   // Set drag image.
 345   if (!image.isNull()) {
 346     drag_utils::SetDragImageOnDataObject(image,
 347         gfx::Size(image.width(), image.height()), image_offset, &data);
 348   }
 349
 350   // Use a local variable to keep track of the contents view window handle.
 351   // It might not be safe to access the instance after DoDragDrop returns
 352   // because the window could be disposed in the nested message loop.
 353   HWND native_window = web_contents_->GetView()->GetNativeView();
 354
 355   // We need to enable recursive tasks on the message loop so we can get
 356   // updates while in the system DoDragDrop loop.
 357   DWORD effect = DROPEFFECT_NONE;
 358   if (run_do_drag_drop) {
 359     // Keep a reference count such that |drag_source_| will not get deleted
 360     // if the contents view window is gone in the nested message loop invoked
 361     // from DoDragDrop.
 362     scoped_refptr<WebDragSource> retain_source(drag_source_);
 363     retain_source->set_data(&data);
 364     data.SetInDragLoop(true);
 365
 366     base::MessageLoop::ScopedNestableTaskAllower allow(
 367         base::MessageLoop::current());
 368     DoDragDrop(ui::OSExchangeDataProviderWin::GetIDataObject(data),
 369                drag_source_,
 370                WebDragOpMaskToWinDragOpMask(ops),
 371                &effect);
 372     retain_source->set_data(NULL);
 373   }
 374
 375   // Bail out immediately if the contents view window is gone.
 376   if (!IsWindow(native_window))
 377     return false;
 378
 379   // Normally, the drop and dragend events get dispatched in the system
 380   // DoDragDrop message loop so it'd be too late to set the effect to send back
 381   // to the renderer here. However, we use PostTask to delay the execution of
 382   // WebDragSource::OnDragSourceDrop, which means that the delayed dragend
 383   // callback to the renderer doesn't run until this has been set to the correct
 384   // value.
 385   drag_source_->set_effect(effect);
 386
 387   return true;
 388 }
 389
 390 void WebContentsDragWin::EndDragging() {
 391   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 392
 393   if (drag_ended_)
 394     return;
 395   drag_ended_ = true;
 396
 397   if (IsBackgroundDraggingSupportEnabled())
 398     DisableBackgroundDraggingSupport();
 399
 400   drag_end_callback_.Run();
 401 }
 402
 403 void WebContentsDragWin::CancelDrag() {
 404   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 405
 406   drag_source_->CancelDrag();
 407 }
 408
 409 void WebContentsDragWin::CloseThread() {
 410   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 411
 412   drag_drop_thread_.reset();
 413 }
 414
 415 void WebContentsDragWin::OnWaitForData() {
 416   DCHECK(drag_drop_thread_id_ == base::PlatformThread::CurrentId());
 417
 418   // When the left button is release and we start to wait for the data, end
 419   // the dragging before DoDragDrop returns. This makes the page leave the drag
 420   // mode so that it can start to process the normal input events.
 421   BrowserThread::PostTask(
 422       BrowserThread::UI,
 423       FROM_HERE,
 424       base::Bind(&WebContentsDragWin::EndDragging, this));
 425 }
 426
 427 void WebContentsDragWin::OnDataObjectDisposed() {
 428   DCHECK(drag_drop_thread_id_ == base::PlatformThread::CurrentId());
 429
 430   // The drag-and-drop thread is only closed after OLE is done with
 431   // DataObjectImpl.
 432   BrowserThread::PostTask(
 433       BrowserThread::UI,
 434       FROM_HERE,
 435       base::Bind(&WebContentsDragWin::CloseThread, this));
 436 }
 437
 438 // static
 439 void WebContentsDragWin::DisableDragDropForTesting() {
 440   run_do_drag_drop = false;
 441 }
 442
 443 }  // namespace content