ui/base/dragdrop/os_exchange_data_provider_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 "ui/base/dragdrop/os_exchange_data_provider_win.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/basictypes.h"
  10 #include "base/files/file_path.h"
  11 #include "base/i18n/file_util_icu.h"
  12 #include "base/logging.h"
  13 #include "base/pickle.h"
  14 #include "base/strings/utf_string_conversions.h"
  15 #include "base/win/scoped_hglobal.h"
  16 #include "net/base/filename_util.h"
  17 #include "ui/base/clipboard/clipboard.h"
  18 #include "ui/base/clipboard/clipboard_util_win.h"
  19 #include "ui/base/dragdrop/file_info.h"
  20 #include "ui/base/l10n/l10n_util.h"
  21 #include "ui/strings/grit/ui_strings.h"
  22 #include "url/gurl.h"
  23
  24 namespace ui {
  25
  26 static const OSExchangeData::CustomFormat& GetRendererTaintCustomType() {
  27   CR_DEFINE_STATIC_LOCAL(
  28       ui::OSExchangeData::CustomFormat,
  29       format,
  30       (ui::Clipboard::GetFormatType("chromium/x-renderer-taint")));
  31   return format;
  32 }
  33
  34 // Creates a new STGMEDIUM object to hold the specified text. The caller
  35 // owns the resulting object. The "Bytes" version does not NULL terminate, the
  36 // string version does.
  37 static STGMEDIUM* GetStorageForBytes(const void* data, size_t bytes);
  38 template <typename T>
  39 static STGMEDIUM* GetStorageForString(const std::basic_string<T>& data);
  40 // Creates the contents of an Internet Shortcut file for the given URL.
  41 static void GetInternetShortcutFileContents(const GURL& url, std::string* data);
  42 // Creates a valid file name given a suggested title and URL.
  43 static void CreateValidFileNameFromTitle(const GURL& url,
  44                                          const base::string16& title,
  45                                          base::string16* validated);
  46 // Creates a new STGMEDIUM object to hold a file.
  47 static STGMEDIUM* GetStorageForFileName(const base::FilePath& path);
  48 static STGMEDIUM* GetIDListStorageForFileName(const base::FilePath& path);
  49 // Creates a File Descriptor for the creation of a file to the given URL and
  50 // returns a handle to it.
  51 static STGMEDIUM* GetStorageForFileDescriptor(const base::FilePath& path);
  52
  53 ///////////////////////////////////////////////////////////////////////////////
  54 // FormatEtcEnumerator
  55
  56 //
  57 // This object implements an enumeration interface. The existence of an
  58 // implementation of this interface is exposed to clients through
  59 // OSExchangeData's EnumFormatEtc method. Our implementation is nobody's
  60 // business but our own, so it lives in this file.
  61 //
  62 // This Windows API is truly a gem. It wants to be an enumerator but assumes
  63 // some sort of sequential data (why not just use an array?). See comments
  64 // throughout.
  65 //
  66 class FormatEtcEnumerator FINAL : public IEnumFORMATETC {
  67  public:
  68   FormatEtcEnumerator(DataObjectImpl::StoredData::const_iterator begin,
  69                       DataObjectImpl::StoredData::const_iterator end);
  70   ~FormatEtcEnumerator();
  71
  72   // IEnumFORMATETC implementation:
  73   HRESULT __stdcall Next(
  74       ULONG count, FORMATETC* elements_array, ULONG* elements_fetched);
  75   HRESULT __stdcall Skip(ULONG skip_count);
  76   HRESULT __stdcall Reset();
  77   HRESULT __stdcall Clone(IEnumFORMATETC** clone);
  78
  79   // IUnknown implementation:
  80   HRESULT __stdcall QueryInterface(const IID& iid, void** object);
  81   ULONG __stdcall AddRef();
  82   ULONG __stdcall Release();
  83
  84  private:
  85   // This can only be called from |CloneFromOther|, since it initializes the
  86   // contents_ from the other enumerator's contents.
  87   FormatEtcEnumerator() : cursor_(0), ref_count_(0) {
  88   }
  89
  90   // Clone a new FormatEtc from another instance of this enumeration.
  91   static FormatEtcEnumerator* CloneFromOther(const FormatEtcEnumerator* other);
  92
  93  private:
  94   // We are _forced_ to use a vector as our internal data model as Windows'
  95   // retarded IEnumFORMATETC API assumes a deterministic ordering of elements
  96   // through methods like Next and Skip. This exposes the underlying data
  97   // structure to the user. Bah.
  98   ScopedVector<FORMATETC> contents_;
  99
 100   // The cursor of the active enumeration - an index into |contents_|.
 101   size_t cursor_;
 102
 103   LONG ref_count_;
 104
 105   DISALLOW_COPY_AND_ASSIGN(FormatEtcEnumerator);
 106 };
 107
 108 // Safely makes a copy of all of the relevant bits of a FORMATETC object.
 109 static void CloneFormatEtc(FORMATETC* source, FORMATETC* clone) {
 110   *clone = *source;
 111   if (source->ptd) {
 112     source->ptd =
 113         static_cast<DVTARGETDEVICE*>(CoTaskMemAlloc(sizeof(DVTARGETDEVICE)));
 114     *(clone->ptd) = *(source->ptd);
 115   }
 116 }
 117
 118 FormatEtcEnumerator::FormatEtcEnumerator(
 119     DataObjectImpl::StoredData::const_iterator start,
 120     DataObjectImpl::StoredData::const_iterator end)
 121     : ref_count_(0), cursor_(0) {
 122   // Copy FORMATETC data from our source into ourselves.
 123   while (start != end) {
 124     FORMATETC* format_etc = new FORMATETC;
 125     CloneFormatEtc(&(*start)->format_etc, format_etc);
 126     contents_.push_back(format_etc);
 127     ++start;
 128   }
 129 }
 130
 131 FormatEtcEnumerator::~FormatEtcEnumerator() {
 132 }
 133
 134 STDMETHODIMP FormatEtcEnumerator::Next(
 135     ULONG count, FORMATETC* elements_array, ULONG* elements_fetched) {
 136   // MSDN says |elements_fetched| is allowed to be NULL if count is 1.
 137   if (!elements_fetched)
 138     DCHECK_EQ(count, 1ul);
 139
 140   // This method copies count elements into |elements_array|.
 141   ULONG index = 0;
 142   while (cursor_ < contents_.size() && index < count) {
 143     CloneFormatEtc(contents_[cursor_], &elements_array[index]);
 144     ++cursor_;
 145     ++index;
 146   }
 147   // The out param is for how many we actually copied.
 148   if (elements_fetched)
 149     *elements_fetched = index;
 150
 151   // If the two don't agree, then we fail.
 152   return index == count ? S_OK : S_FALSE;
 153 }
 154
 155 STDMETHODIMP FormatEtcEnumerator::Skip(ULONG skip_count) {
 156   cursor_ += skip_count;
 157   // MSDN implies it's OK to leave the enumerator trashed.
 158   // "Whatever you say, boss"
 159   return cursor_ <= contents_.size() ? S_OK : S_FALSE;
 160 }
 161
 162 STDMETHODIMP FormatEtcEnumerator::Reset() {
 163   cursor_ = 0;
 164   return S_OK;
 165 }
 166
 167 STDMETHODIMP FormatEtcEnumerator::Clone(IEnumFORMATETC** clone) {
 168   // Clone the current enumerator in its exact state, including cursor.
 169   FormatEtcEnumerator* e = CloneFromOther(this);
 170   e->AddRef();
 171   *clone = e;
 172   return S_OK;
 173 }
 174
 175 STDMETHODIMP FormatEtcEnumerator::QueryInterface(const IID& iid,
 176                                                  void** object) {
 177   *object = NULL;
 178   if (IsEqualIID(iid, IID_IUnknown) || IsEqualIID(iid, IID_IEnumFORMATETC)) {
 179     *object = this;
 180   } else {
 181     return E_NOINTERFACE;
 182   }
 183   AddRef();
 184   return S_OK;
 185 }
 186
 187 ULONG FormatEtcEnumerator::AddRef() {
 188   return InterlockedIncrement(&ref_count_);
 189 }
 190
 191 ULONG FormatEtcEnumerator::Release() {
 192   if (InterlockedDecrement(&ref_count_) == 0) {
 193     ULONG copied_refcnt = ref_count_;
 194     delete this;
 195     return copied_refcnt;
 196   }
 197   return ref_count_;
 198 }
 199
 200 // static
 201 FormatEtcEnumerator* FormatEtcEnumerator::CloneFromOther(
 202     const FormatEtcEnumerator* other) {
 203   FormatEtcEnumerator* e = new FormatEtcEnumerator;
 204   // Copy FORMATETC data from our source into ourselves.
 205   ScopedVector<FORMATETC>::const_iterator start = other->contents_.begin();
 206   while (start != other->contents_.end()) {
 207     FORMATETC* format_etc = new FORMATETC;
 208     CloneFormatEtc(*start, format_etc);
 209     e->contents_.push_back(format_etc);
 210     ++start;
 211   }
 212   // Carry over
 213   e->cursor_ = other->cursor_;
 214   return e;
 215 }
 216
 217 ///////////////////////////////////////////////////////////////////////////////
 218 // OSExchangeDataProviderWin, public:
 219
 220 // static
 221 bool OSExchangeDataProviderWin::HasPlainTextURL(IDataObject* source) {
 222   base::string16 plain_text;
 223   return (ClipboardUtil::GetPlainText(source, &plain_text) &&
 224           !plain_text.empty() && GURL(plain_text).is_valid());
 225 }
 226
 227 // static
 228 bool OSExchangeDataProviderWin::GetPlainTextURL(IDataObject* source,
 229                                                 GURL* url) {
 230   base::string16 plain_text;
 231   if (ClipboardUtil::GetPlainText(source, &plain_text) &&
 232       !plain_text.empty()) {
 233     GURL gurl(plain_text);
 234     if (gurl.is_valid()) {
 235       *url = gurl;
 236       return true;
 237     }
 238   }
 239   return false;
 240 }
 241
 242 // static
 243 DataObjectImpl* OSExchangeDataProviderWin::GetDataObjectImpl(
 244     const OSExchangeData& data) {
 245   return static_cast<const OSExchangeDataProviderWin*>(&data.provider())->
 246       data_.get();
 247 }
 248
 249 // static
 250 IDataObject* OSExchangeDataProviderWin::GetIDataObject(
 251     const OSExchangeData& data) {
 252   return static_cast<const OSExchangeDataProviderWin*>(&data.provider())->
 253       data_object();
 254 }
 255
 256 // static
 257 IDataObjectAsyncCapability* OSExchangeDataProviderWin::GetIAsyncOperation(
 258     const OSExchangeData& data) {
 259   return static_cast<const OSExchangeDataProviderWin*>(&data.provider())->
 260       async_operation();
 261 }
 262
 263 OSExchangeDataProviderWin::OSExchangeDataProviderWin(IDataObject* source)
 264     : data_(new DataObjectImpl()),
 265       source_object_(source) {
 266 }
 267
 268 OSExchangeDataProviderWin::OSExchangeDataProviderWin()
 269     : data_(new DataObjectImpl()),
 270       source_object_(data_.get()) {
 271 }
 272
 273 OSExchangeDataProviderWin::~OSExchangeDataProviderWin() {
 274 }
 275
 276 OSExchangeData::Provider* OSExchangeDataProviderWin::Clone() const {
 277   return new OSExchangeDataProviderWin(data_object());
 278 }
 279
 280 void OSExchangeDataProviderWin::MarkOriginatedFromRenderer() {
 281   STGMEDIUM* storage = GetStorageForString(std::string());
 282   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 283       GetRendererTaintCustomType().ToFormatEtc(), storage));
 284 }
 285
 286 bool OSExchangeDataProviderWin::DidOriginateFromRenderer() const {
 287   return HasCustomFormat(GetRendererTaintCustomType());
 288 }
 289
 290 void OSExchangeDataProviderWin::SetString(const base::string16& data) {
 291   STGMEDIUM* storage = GetStorageForString(data);
 292   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 293       Clipboard::GetPlainTextWFormatType().ToFormatEtc(), storage));
 294
 295   // Also add the UTF8-encoded version.
 296   storage = GetStorageForString(base::UTF16ToUTF8(data));
 297   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 298       Clipboard::GetPlainTextFormatType().ToFormatEtc(), storage));
 299 }
 300
 301 void OSExchangeDataProviderWin::SetURL(const GURL& url,
 302                                        const base::string16& title) {
 303   // NOTE WELL:
 304   // Every time you change the order of the first two CLIPFORMATS that get
 305   // added here, you need to update the EnumerationViaCOM test case in
 306   // the _unittest.cc file to reflect the new arrangement otherwise that test
 307   // will fail! It assumes an insertion order.
 308
 309   // Add text/x-moz-url for drags from Firefox
 310   base::string16 x_moz_url_str = base::UTF8ToUTF16(url.spec());
 311   x_moz_url_str += '\n';
 312   x_moz_url_str += title;
 313   STGMEDIUM* storage = GetStorageForString(x_moz_url_str);
 314   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 315       Clipboard::GetMozUrlFormatType().ToFormatEtc(), storage));
 316
 317   // Add a .URL shortcut file for dragging to Explorer.
 318   base::string16 valid_file_name;
 319   CreateValidFileNameFromTitle(url, title, &valid_file_name);
 320   std::string shortcut_url_file_contents;
 321   GetInternetShortcutFileContents(url, &shortcut_url_file_contents);
 322   SetFileContents(base::FilePath(valid_file_name), shortcut_url_file_contents);
 323
 324   // Add a UniformResourceLocator link for apps like IE and Word.
 325   storage = GetStorageForString(base::UTF8ToUTF16(url.spec()));
 326   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 327       Clipboard::GetUrlWFormatType().ToFormatEtc(), storage));
 328   storage = GetStorageForString(url.spec());
 329   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 330       Clipboard::GetUrlFormatType().ToFormatEtc(), storage));
 331
 332   // TODO(beng): add CF_HTML.
 333   // http://code.google.com/p/chromium/issues/detail?id=6767
 334
 335   // Also add text representations (these should be last since they're the
 336   // least preferable).
 337   SetString(base::UTF8ToUTF16(url.spec()));
 338 }
 339
 340 void OSExchangeDataProviderWin::SetFilename(const base::FilePath& path) {
 341   STGMEDIUM* storage = GetStorageForFileName(path);
 342   DataObjectImpl::StoredDataInfo* info = new DataObjectImpl::StoredDataInfo(
 343       Clipboard::GetCFHDropFormatType().ToFormatEtc(), storage);
 344   data_->contents_.push_back(info);
 345
 346   storage = GetIDListStorageForFileName(path);
 347   if (!storage)
 348     return;
 349   info = new DataObjectImpl::StoredDataInfo(
 350       Clipboard::GetIDListFormatType().ToFormatEtc(), storage);
 351   data_->contents_.push_back(info);
 352 }
 353
 354 void OSExchangeDataProviderWin::SetFilenames(
 355     const std::vector<FileInfo>& filenames) {
 356   for (size_t i = 0; i < filenames.size(); ++i) {
 357     STGMEDIUM* storage = GetStorageForFileName(filenames[i].path);
 358     DataObjectImpl::StoredDataInfo* info = new DataObjectImpl::StoredDataInfo(
 359         Clipboard::GetCFHDropFormatType().ToFormatEtc(), storage);
 360     data_->contents_.push_back(info);
 361   }
 362 }
 363
 364 void OSExchangeDataProviderWin::SetPickledData(
 365     const OSExchangeData::CustomFormat& format,
 366     const Pickle& data) {
 367   STGMEDIUM* storage = GetStorageForBytes(data.data(), data.size());
 368   data_->contents_.push_back(
 369       new DataObjectImpl::StoredDataInfo(format.ToFormatEtc(), storage));
 370 }
 371
 372 void OSExchangeDataProviderWin::SetFileContents(
 373     const base::FilePath& filename,
 374     const std::string& file_contents) {
 375   // Add CFSTR_FILEDESCRIPTOR
 376   STGMEDIUM* storage = GetStorageForFileDescriptor(filename);
 377   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 378       Clipboard::GetFileDescriptorFormatType().ToFormatEtc(), storage));
 379
 380   // Add CFSTR_FILECONTENTS
 381   storage = GetStorageForBytes(file_contents.data(), file_contents.length());
 382   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 383       Clipboard::GetFileContentZeroFormatType().ToFormatEtc(), storage));
 384 }
 385
 386 void OSExchangeDataProviderWin::SetHtml(const base::string16& html,
 387                                         const GURL& base_url) {
 388   // Add both MS CF_HTML and text/html format.  CF_HTML should be in utf-8.
 389   std::string utf8_html = base::UTF16ToUTF8(html);
 390   std::string url = base_url.is_valid() ? base_url.spec() : std::string();
 391
 392   std::string cf_html = ClipboardUtil::HtmlToCFHtml(utf8_html, url);
 393   STGMEDIUM* storage = GetStorageForBytes(cf_html.c_str(), cf_html.size());
 394   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 395       Clipboard::GetHtmlFormatType().ToFormatEtc(), storage));
 396
 397   STGMEDIUM* storage_plain = GetStorageForBytes(utf8_html.c_str(),
 398                                                 utf8_html.size());
 399   data_->contents_.push_back(new DataObjectImpl::StoredDataInfo(
 400       Clipboard::GetTextHtmlFormatType().ToFormatEtc(), storage_plain));
 401 }
 402
 403 bool OSExchangeDataProviderWin::GetString(base::string16* data) const {
 404   return ClipboardUtil::GetPlainText(source_object_, data);
 405 }
 406
 407 bool OSExchangeDataProviderWin::GetURLAndTitle(
 408     OSExchangeData::FilenameToURLPolicy policy,
 409     GURL* url,
 410     base::string16* title) const {
 411   base::string16 url_str;
 412   bool success = ClipboardUtil::GetUrl(
 413       source_object_,
 414       url,
 415       title,
 416       policy == OSExchangeData::CONVERT_FILENAMES ? true : false);
 417   if (success) {
 418     DCHECK(url->is_valid());
 419     return true;
 420   } else if (GetPlainTextURL(source_object_, url)) {
 421     if (url->is_valid())
 422       *title = net::GetSuggestedFilename(*url, "", "", "", "", std::string());
 423     else
 424       title->clear();
 425     return true;
 426   }
 427   return false;
 428 }
 429
 430 bool OSExchangeDataProviderWin::GetFilename(base::FilePath* path) const {
 431   std::vector<base::string16> filenames;
 432   bool success = ClipboardUtil::GetFilenames(source_object_, &filenames);
 433   if (success)
 434     *path = base::FilePath(filenames[0]);
 435   return success;
 436 }
 437
 438 bool OSExchangeDataProviderWin::GetFilenames(
 439     std::vector<FileInfo>* filenames) const {
 440   std::vector<base::string16> filenames_local;
 441   bool success = ClipboardUtil::GetFilenames(source_object_, &filenames_local);
 442   if (success) {
 443     for (size_t i = 0; i < filenames_local.size(); ++i)
 444       filenames->push_back(
 445           FileInfo(base::FilePath(filenames_local[i]), base::FilePath()));
 446   }
 447   return success;
 448 }
 449
 450 bool OSExchangeDataProviderWin::GetPickledData(
 451     const OSExchangeData::CustomFormat& format,
 452     Pickle* data) const {
 453   DCHECK(data);
 454   bool success = false;
 455   STGMEDIUM medium;
 456   FORMATETC format_etc = format.ToFormatEtc();
 457   if (SUCCEEDED(source_object_->GetData(&format_etc, &medium))) {
 458     if (medium.tymed & TYMED_HGLOBAL) {
 459       base::win::ScopedHGlobal<char*> c_data(medium.hGlobal);
 460       DCHECK_GT(c_data.Size(), 0u);
 461       *data = Pickle(c_data.get(), static_cast<int>(c_data.Size()));
 462       success = true;
 463     }
 464     ReleaseStgMedium(&medium);
 465   }
 466   return success;
 467 }
 468
 469 bool OSExchangeDataProviderWin::GetFileContents(
 470     base::FilePath* filename,
 471     std::string* file_contents) const {
 472   base::string16 filename_str;
 473   if (!ClipboardUtil::GetFileContents(source_object_, &filename_str,
 474                                       file_contents)) {
 475     return false;
 476   }
 477   *filename = base::FilePath(filename_str);
 478   return true;
 479 }
 480
 481 bool OSExchangeDataProviderWin::GetHtml(base::string16* html,
 482                                         GURL* base_url) const {
 483   std::string url;
 484   bool success = ClipboardUtil::GetHtml(source_object_, html, &url);
 485   if (success)
 486     *base_url = GURL(url);
 487   return success;
 488 }
 489
 490 bool OSExchangeDataProviderWin::HasString() const {
 491   return ClipboardUtil::HasPlainText(source_object_);
 492 }
 493
 494 bool OSExchangeDataProviderWin::HasURL(
 495     OSExchangeData::FilenameToURLPolicy policy) const {
 496   return (ClipboardUtil::HasUrl(
 497               source_object_,
 498               policy == OSExchangeData::CONVERT_FILENAMES ? true : false) ||
 499           HasPlainTextURL(source_object_));
 500 }
 501
 502 bool OSExchangeDataProviderWin::HasFile() const {
 503   return ClipboardUtil::HasFilenames(source_object_);
 504 }
 505
 506 bool OSExchangeDataProviderWin::HasFileContents() const {
 507   return ClipboardUtil::HasFileContents(source_object_);
 508 }
 509
 510 bool OSExchangeDataProviderWin::HasHtml() const {
 511   return ClipboardUtil::HasHtml(source_object_);
 512 }
 513
 514 bool OSExchangeDataProviderWin::HasCustomFormat(
 515     const OSExchangeData::CustomFormat& format) const {
 516   FORMATETC format_etc = format.ToFormatEtc();
 517   return (source_object_->QueryGetData(&format_etc) == S_OK);
 518 }
 519
 520 void OSExchangeDataProviderWin::SetDownloadFileInfo(
 521     const OSExchangeData::DownloadFileInfo& download) {
 522   // If the filename is not provided, set storage to NULL to indicate that
 523   // the delay rendering will be used.
 524   // TODO(dcheng): Is it actually possible for filename to be empty here? I
 525   // think we always synthesize one in WebContentsDragWin.
 526   STGMEDIUM* storage = NULL;
 527   if (!download.filename.empty())
 528     storage = GetStorageForFileName(download.filename);
 529
 530   // Add CF_HDROP.
 531   DataObjectImpl::StoredDataInfo* info = new DataObjectImpl::StoredDataInfo(
 532       Clipboard::GetCFHDropFormatType().ToFormatEtc(), storage);
 533   info->downloader = download.downloader;
 534   data_->contents_.push_back(info);
 535 }
 536
 537 void OSExchangeDataProviderWin::SetDragImage(
 538     const gfx::ImageSkia& image,
 539     const gfx::Vector2d& cursor_offset) {
 540   drag_image_ = image;
 541   drag_image_offset_ = cursor_offset;
 542 }
 543
 544 const gfx::ImageSkia& OSExchangeDataProviderWin::GetDragImage() const {
 545   return drag_image_;
 546 }
 547
 548 const gfx::Vector2d& OSExchangeDataProviderWin::GetDragImageOffset() const {
 549   return drag_image_offset_;
 550 }
 551
 552 ///////////////////////////////////////////////////////////////////////////////
 553 // DataObjectImpl, IDataObject implementation:
 554
 555 // The following function, DuplicateMedium, is derived from WCDataObject.cpp
 556 // in the WebKit source code. This is the license information for the file:
 557 /*
 558  * Copyright (C) 2007 Apple Inc.  All rights reserved.
 559  *
 560  * Redistribution and use in source and binary forms, with or without
 561  * modification, are permitted provided that the following conditions
 562  * are met:
 563  * 1. Redistributions of source code must retain the above copyright
 564  *    notice, this list of conditions and the following disclaimer.
 565  * 2. Redistributions in binary form must reproduce the above copyright
 566  *    notice, this list of conditions and the following disclaimer in the
 567  *    documentation and/or other materials provided with the distribution.
 568  *
 569  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 570  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 571  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 572  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 573  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 574  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 575  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 576  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 577  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 578  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 579  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 580  */
 581 static void DuplicateMedium(CLIPFORMAT source_clipformat,
 582                             STGMEDIUM* source,
 583                             STGMEDIUM* destination) {
 584   switch (source->tymed) {
 585     case TYMED_HGLOBAL:
 586       destination->hGlobal =
 587           static_cast<HGLOBAL>(OleDuplicateData(
 588               source->hGlobal, source_clipformat, 0));
 589       break;
 590     case TYMED_MFPICT:
 591       destination->hMetaFilePict =
 592           static_cast<HMETAFILEPICT>(OleDuplicateData(
 593               source->hMetaFilePict, source_clipformat, 0));
 594       break;
 595     case TYMED_GDI:
 596       destination->hBitmap =
 597           static_cast<HBITMAP>(OleDuplicateData(
 598               source->hBitmap, source_clipformat, 0));
 599       break;
 600     case TYMED_ENHMF:
 601       destination->hEnhMetaFile =
 602           static_cast<HENHMETAFILE>(OleDuplicateData(
 603               source->hEnhMetaFile, source_clipformat, 0));
 604       break;
 605     case TYMED_FILE:
 606       destination->lpszFileName =
 607           static_cast<LPOLESTR>(OleDuplicateData(
 608               source->lpszFileName, source_clipformat, 0));
 609       break;
 610     case TYMED_ISTREAM:
 611       destination->pstm = source->pstm;
 612       destination->pstm->AddRef();
 613       break;
 614     case TYMED_ISTORAGE:
 615       destination->pstg = source->pstg;
 616       destination->pstg->AddRef();
 617       break;
 618   }
 619
 620   destination->tymed = source->tymed;
 621   destination->pUnkForRelease = source->pUnkForRelease;
 622   if (destination->pUnkForRelease)
 623     destination->pUnkForRelease->AddRef();
 624 }
 625
 626 DataObjectImpl::DataObjectImpl()
 627     : is_aborting_(false),
 628       in_drag_loop_(false),
 629       in_async_mode_(false),
 630       async_operation_started_(false),
 631       observer_(NULL) {
 632 }
 633
 634 DataObjectImpl::~DataObjectImpl() {
 635   StopDownloads();
 636   if (observer_)
 637     observer_->OnDataObjectDisposed();
 638 }
 639
 640 void DataObjectImpl::StopDownloads() {
 641   for (StoredData::iterator iter = contents_.begin();
 642        iter != contents_.end(); ++iter) {
 643     if ((*iter)->downloader.get()) {
 644       (*iter)->downloader->Stop();
 645       (*iter)->downloader = 0;
 646     }
 647   }
 648 }
 649
 650 void DataObjectImpl::RemoveData(const FORMATETC& format) {
 651   if (format.ptd)
 652     return;  // Don't attempt to compare target devices.
 653
 654   for (StoredData::iterator i = contents_.begin(); i != contents_.end(); ++i) {
 655     if (!(*i)->format_etc.ptd &&
 656         format.cfFormat == (*i)->format_etc.cfFormat &&
 657         format.dwAspect == (*i)->format_etc.dwAspect &&
 658         format.lindex == (*i)->format_etc.lindex &&
 659         format.tymed == (*i)->format_etc.tymed) {
 660       contents_.erase(i);
 661       return;
 662     }
 663   }
 664 }
 665
 666 void DataObjectImpl::OnDownloadCompleted(const base::FilePath& file_path) {
 667   DataObjectImpl::StoredData::iterator iter = contents_.begin();
 668   for (; iter != contents_.end(); ++iter) {
 669     if ((*iter)->format_etc.cfFormat == CF_HDROP) {
 670       // Release the old storage.
 671       if ((*iter)->owns_medium) {
 672         ReleaseStgMedium((*iter)->medium);
 673         delete (*iter)->medium;
 674       }
 675
 676       // Update the storage.
 677       (*iter)->owns_medium = true;
 678       (*iter)->medium = GetStorageForFileName(file_path);
 679
 680       break;
 681     }
 682   }
 683   DCHECK(iter != contents_.end());
 684 }
 685
 686 void DataObjectImpl::OnDownloadAborted() {
 687 }
 688
 689 HRESULT DataObjectImpl::GetData(FORMATETC* format_etc, STGMEDIUM* medium) {
 690   if (is_aborting_)
 691     return DV_E_FORMATETC;
 692
 693   StoredData::iterator iter = contents_.begin();
 694   while (iter != contents_.end()) {
 695     if ((*iter)->format_etc.cfFormat == format_etc->cfFormat &&
 696         (*iter)->format_etc.lindex == format_etc->lindex &&
 697         ((*iter)->format_etc.tymed & format_etc->tymed)) {
 698       // If medium is NULL, delay-rendering will be used.
 699       if ((*iter)->medium) {
 700         DuplicateMedium((*iter)->format_etc.cfFormat, (*iter)->medium, medium);
 701       } else {
 702         // Fail all GetData() attempts for DownloadURL data if the drag and drop
 703         // operation is still in progress.
 704         if (in_drag_loop_)
 705           return DV_E_FORMATETC;
 706
 707         bool wait_for_data = false;
 708
 709         // In async mode, we do not want to start waiting for the data before
 710         // the async operation is started. This is because we want to postpone
 711         // until Shell kicks off a background thread to do the work so that
 712         // we do not block the UI thread.
 713         if (!in_async_mode_ || async_operation_started_)
 714           wait_for_data = true;
 715
 716         if (!wait_for_data)
 717           return DV_E_FORMATETC;
 718
 719         // Notify the observer we start waiting for the data. This gives
 720         // an observer a chance to end the drag and drop.
 721         if (observer_)
 722           observer_->OnWaitForData();
 723
 724         // Now we can start the download.
 725         if ((*iter)->downloader.get()) {
 726           (*iter)->downloader->Start(this);
 727           if (!(*iter)->downloader->Wait()) {
 728             is_aborting_ = true;
 729             return DV_E_FORMATETC;
 730           }
 731         }
 732
 733         // The stored data should have been updated with the final version.
 734         // So we just need to call this function again to retrieve it.
 735         return GetData(format_etc, medium);
 736       }
 737       return S_OK;
 738     }
 739     ++iter;
 740   }
 741
 742   return DV_E_FORMATETC;
 743 }
 744
 745 HRESULT DataObjectImpl::GetDataHere(FORMATETC* format_etc,
 746                                     STGMEDIUM* medium) {
 747   return DATA_E_FORMATETC;
 748 }
 749
 750 HRESULT DataObjectImpl::QueryGetData(FORMATETC* format_etc) {
 751   StoredData::const_iterator iter = contents_.begin();
 752   while (iter != contents_.end()) {
 753     if ((*iter)->format_etc.cfFormat == format_etc->cfFormat)
 754       return S_OK;
 755     ++iter;
 756   }
 757   return DV_E_FORMATETC;
 758 }
 759
 760 HRESULT DataObjectImpl::GetCanonicalFormatEtc(
 761     FORMATETC* format_etc, FORMATETC* result) {
 762   format_etc->ptd = NULL;
 763   return E_NOTIMPL;
 764 }
 765
 766 HRESULT DataObjectImpl::SetData(
 767     FORMATETC* format_etc, STGMEDIUM* medium, BOOL should_release) {
 768   RemoveData(*format_etc);
 769
 770   STGMEDIUM* local_medium = new STGMEDIUM;
 771   if (should_release) {
 772     *local_medium = *medium;
 773   } else {
 774     DuplicateMedium(format_etc->cfFormat, medium, local_medium);
 775   }
 776
 777   DataObjectImpl::StoredDataInfo* info =
 778       new DataObjectImpl::StoredDataInfo(*format_etc, local_medium);
 779   info->medium->tymed = format_etc->tymed;
 780   info->owns_medium = !!should_release;
 781   // Make newly added data appear first.
 782   // TODO(dcheng): Make various setters agree whether elements should be
 783   // prioritized from front to back or back to front.
 784   contents_.insert(contents_.begin(), info);
 785
 786   return S_OK;
 787 }
 788
 789 HRESULT DataObjectImpl::EnumFormatEtc(
 790     DWORD direction, IEnumFORMATETC** enumerator) {
 791   if (direction == DATADIR_GET) {
 792     FormatEtcEnumerator* e =
 793         new FormatEtcEnumerator(contents_.begin(), contents_.end());
 794     e->AddRef();
 795     *enumerator = e;
 796     return S_OK;
 797   }
 798   return E_NOTIMPL;
 799 }
 800
 801 HRESULT DataObjectImpl::DAdvise(
 802     FORMATETC* format_etc, DWORD advf, IAdviseSink* sink, DWORD* connection) {
 803   return OLE_E_ADVISENOTSUPPORTED;
 804 }
 805
 806 HRESULT DataObjectImpl::DUnadvise(DWORD connection) {
 807   return OLE_E_ADVISENOTSUPPORTED;
 808 }
 809
 810 HRESULT DataObjectImpl::EnumDAdvise(IEnumSTATDATA** enumerator) {
 811   return OLE_E_ADVISENOTSUPPORTED;
 812 }
 813
 814 ///////////////////////////////////////////////////////////////////////////////
 815 // DataObjectImpl, IDataObjectAsyncCapability implementation:
 816
 817 HRESULT DataObjectImpl::EndOperation(
 818     HRESULT result, IBindCtx* reserved, DWORD effects) {
 819   async_operation_started_ = false;
 820   return S_OK;
 821 }
 822
 823 HRESULT DataObjectImpl::GetAsyncMode(BOOL* is_op_async) {
 824   *is_op_async = in_async_mode_ ? TRUE : FALSE;
 825   return S_OK;
 826 }
 827
 828 HRESULT DataObjectImpl::InOperation(BOOL* in_async_op) {
 829   *in_async_op = async_operation_started_ ? TRUE : FALSE;
 830   return S_OK;
 831 }
 832
 833 HRESULT DataObjectImpl::SetAsyncMode(BOOL do_op_async) {
 834   in_async_mode_ = (do_op_async == TRUE);
 835   return S_OK;
 836 }
 837
 838 HRESULT DataObjectImpl::StartOperation(IBindCtx* reserved) {
 839   async_operation_started_ = true;
 840   return S_OK;
 841 }
 842
 843 ///////////////////////////////////////////////////////////////////////////////
 844 // DataObjectImpl, IUnknown implementation:
 845
 846 HRESULT DataObjectImpl::QueryInterface(const IID& iid, void** object) {
 847   if (!object)
 848     return E_POINTER;
 849   if (IsEqualIID(iid, IID_IDataObject) || IsEqualIID(iid, IID_IUnknown)) {
 850     *object = static_cast<IDataObject*>(this);
 851   } else if (in_async_mode_ &&
 852              IsEqualIID(iid, __uuidof(IDataObjectAsyncCapability))) {
 853     *object = static_cast<IDataObjectAsyncCapability*>(this);
 854   } else {
 855     *object = NULL;
 856     return E_NOINTERFACE;
 857   }
 858   AddRef();
 859   return S_OK;
 860 }
 861
 862 ULONG DataObjectImpl::AddRef() {
 863   base::RefCountedThreadSafe<DownloadFileObserver>::AddRef();
 864   return 0;
 865 }
 866
 867 ULONG DataObjectImpl::Release() {
 868   base::RefCountedThreadSafe<DownloadFileObserver>::Release();
 869   return 0;
 870 }
 871
 872 ///////////////////////////////////////////////////////////////////////////////
 873 // DataObjectImpl, private:
 874
 875 static STGMEDIUM* GetStorageForBytes(const void* data, size_t bytes) {
 876   HANDLE handle = GlobalAlloc(GPTR, static_cast<int>(bytes));
 877   if (handle) {
 878     base::win::ScopedHGlobal<uint8*> scoped(handle);
 879     memcpy(scoped.get(), data, bytes);
 880   }
 881
 882   STGMEDIUM* storage = new STGMEDIUM;
 883   storage->hGlobal = handle;
 884   storage->tymed = TYMED_HGLOBAL;
 885   storage->pUnkForRelease = NULL;
 886   return storage;
 887 }
 888
 889 template <typename T>
 890 static STGMEDIUM* GetStorageForString(const std::basic_string<T>& data) {
 891   return GetStorageForBytes(
 892       data.c_str(),
 893       (data.size() + 1) * sizeof(typename std::basic_string<T>::value_type));
 894 }
 895
 896 static void GetInternetShortcutFileContents(const GURL& url,
 897                                             std::string* data) {
 898   DCHECK(data);
 899   static const std::string kInternetShortcutFileStart =
 900       "[InternetShortcut]\r\nURL=";
 901   static const std::string kInternetShortcutFileEnd =
 902       "\r\n";
 903   *data = kInternetShortcutFileStart + url.spec() + kInternetShortcutFileEnd;
 904 }
 905
 906 static void CreateValidFileNameFromTitle(const GURL& url,
 907                                          const base::string16& title,
 908                                          base::string16* validated) {
 909   if (title.empty()) {
 910     if (url.is_valid()) {
 911       *validated = net::GetSuggestedFilename(url, "", "", "", "",
 912                                              std::string());
 913     } else {
 914       // Nothing else can be done, just use a default.
 915       *validated =
 916           l10n_util::GetStringUTF16(IDS_APP_UNTITLED_SHORTCUT_FILE_NAME);
 917     }
 918   } else {
 919     *validated = title;
 920     base::i18n::ReplaceIllegalCharactersInPath(validated, '-');
 921   }
 922   static const wchar_t extension[] = L".url";
 923   static const size_t max_length = MAX_PATH - arraysize(extension);
 924   if (validated->size() > max_length)
 925     validated->erase(max_length);
 926   *validated += extension;
 927 }
 928
 929 static STGMEDIUM* GetStorageForFileName(const base::FilePath& path) {
 930   const size_t kDropSize = sizeof(DROPFILES);
 931   const size_t kTotalBytes =
 932       kDropSize + (path.value().length() + 2) * sizeof(wchar_t);
 933   HANDLE hdata = GlobalAlloc(GMEM_MOVEABLE, kTotalBytes);
 934
 935   base::win::ScopedHGlobal<DROPFILES*> locked_mem(hdata);
 936   DROPFILES* drop_files = locked_mem.get();
 937   drop_files->pFiles = sizeof(DROPFILES);
 938   drop_files->fWide = TRUE;
 939   wchar_t* data = reinterpret_cast<wchar_t*>(
 940       reinterpret_cast<BYTE*>(drop_files) + kDropSize);
 941   const size_t copy_size = (path.value().length() + 1) * sizeof(wchar_t);
 942   memcpy(data, path.value().c_str(), copy_size);
 943   data[path.value().length() + 1] = L'\0';  // Double NULL
 944
 945   STGMEDIUM* storage = new STGMEDIUM;
 946   storage->tymed = TYMED_HGLOBAL;
 947   storage->hGlobal = hdata;
 948   storage->pUnkForRelease = NULL;
 949   return storage;
 950 }
 951
 952 static LPITEMIDLIST PIDLNext(LPITEMIDLIST pidl) {
 953   return reinterpret_cast<LPITEMIDLIST>(
 954       reinterpret_cast<BYTE*>(pidl) + pidl->mkid.cb);
 955 }
 956
 957 static size_t PIDLSize(LPITEMIDLIST pidl) {
 958   size_t s = 0;
 959   while (pidl->mkid.cb > 0) {
 960     s += pidl->mkid.cb;
 961     pidl = PIDLNext(pidl);
 962   }
 963   // We add 2 because an LPITEMIDLIST is terminated by two NULL bytes.
 964   return 2 + s;
 965 }
 966
 967 static LPITEMIDLIST GetNthPIDL(CIDA* cida, int n) {
 968   return reinterpret_cast<LPITEMIDLIST>(
 969       reinterpret_cast<LPBYTE>(cida) + cida->aoffset[n]);
 970 }
 971
 972 static LPITEMIDLIST GetPidlFromPath(const base::FilePath& path) {
 973   LPITEMIDLIST pidl = NULL;
 974   LPSHELLFOLDER desktop_folder = NULL;
 975   LPWSTR path_str = const_cast<LPWSTR>(path.value().c_str());
 976
 977   if (FAILED(SHGetDesktopFolder(&desktop_folder)))
 978     return NULL;
 979
 980   HRESULT hr = desktop_folder->ParseDisplayName(
 981       NULL, NULL, path_str, NULL, &pidl, NULL);
 982
 983   return SUCCEEDED(hr) ? pidl : NULL;
 984 }
 985
 986 static STGMEDIUM* GetIDListStorageForFileName(const base::FilePath& path) {
 987   LPITEMIDLIST pidl = GetPidlFromPath(path);
 988   if (!pidl)
 989     return NULL;
 990
 991   // When using CFSTR_SHELLIDLIST the hGlobal field of the STGMEDIUM is a
 992   // pointer to a CIDA*. A CIDA is a variable length struct that contains a PIDL
 993   // count (a UINT), an array of offsets of the following PIDLs (a UINT[]) and
 994   // then a series of PIDLs laid out contiguously in memory. A PIDL is
 995   // represented by an ITEMIDLIST struct, which contains a single SHITEMID.
 996   // Despite only containing a single SHITEMID, ITEMIDLISTs are so-named because
 997   // SHITEMIDs contain their own size and so given one, the next can be found by
 998   // looking at the section of memory after it. The end of a list is indicated
 999   // by two NULL bytes.
1000   // Here we require two PIDLs - the first PIDL is the parent folder and is
1001   // NULL here to indicate that the parent folder is the desktop, and the second
1002   // is the PIDL of |path|.
1003   const size_t kPIDLCountSize = sizeof(UINT);
1004   const size_t kPIDLOffsetsSize = 2 * sizeof(UINT);
1005   const size_t kFirstPIDLOffset = kPIDLCountSize + kPIDLOffsetsSize;
1006   const size_t kFirstPIDLSize = 2;  // Empty PIDL - 2 NULL bytes.
1007   const size_t kSecondPIDLSize = PIDLSize(pidl);
1008   const size_t kCIDASize = kFirstPIDLOffset + kFirstPIDLSize + kSecondPIDLSize;
1009   HANDLE hdata = GlobalAlloc(GMEM_MOVEABLE, kCIDASize);
1010
1011   base::win::ScopedHGlobal<CIDA*> locked_mem(hdata);
1012   CIDA* cida = locked_mem.get();
1013   cida->cidl = 1;     // We have one PIDL (not including the 0th root PIDL).
1014   cida->aoffset[0] = kFirstPIDLOffset;
1015   cida->aoffset[1] = kFirstPIDLOffset + kFirstPIDLSize;
1016   LPITEMIDLIST idl = GetNthPIDL(cida, 0);
1017   idl->mkid.cb = 0;
1018   idl->mkid.abID[0] = 0;
1019   idl = GetNthPIDL(cida, 1);
1020   memcpy(idl, pidl, kSecondPIDLSize);
1021
1022   STGMEDIUM* storage = new STGMEDIUM;
1023   storage->tymed = TYMED_HGLOBAL;
1024   storage->hGlobal = hdata;
1025   storage->pUnkForRelease = NULL;
1026   return storage;
1027 }
1028
1029 static STGMEDIUM* GetStorageForFileDescriptor(
1030     const base::FilePath& path) {
1031   base::string16 file_name = path.value();
1032   DCHECK(!file_name.empty());
1033   HANDLE hdata = GlobalAlloc(GPTR, sizeof(FILEGROUPDESCRIPTOR));
1034   base::win::ScopedHGlobal<FILEGROUPDESCRIPTOR*> locked_mem(hdata);
1035
1036   FILEGROUPDESCRIPTOR* descriptor = locked_mem.get();
1037   descriptor->cItems = 1;
1038   descriptor->fgd[0].dwFlags = FD_LINKUI;
1039   wcsncpy_s(descriptor->fgd[0].cFileName, MAX_PATH, file_name.c_str(),
1040             std::min(file_name.size(), static_cast<size_t>(MAX_PATH - 1u)));
1041
1042   STGMEDIUM* storage = new STGMEDIUM;
1043   storage->tymed = TYMED_HGLOBAL;
1044   storage->hGlobal = hdata;
1045   storage->pUnkForRelease = NULL;
1046   return storage;
1047 }
1048
1049 ///////////////////////////////////////////////////////////////////////////////
1050 // OSExchangeData, public:
1051
1052 // static
1053 OSExchangeData::Provider* OSExchangeData::CreateProvider() {
1054   return new OSExchangeDataProviderWin();
1055 }
1056
1057 }  // namespace ui