src/chrome/browser/spellchecker/spellcheck_hunspell_dictionary.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 "chrome/browser/spellchecker/spellcheck_hunspell_dictionary.h"
   6
   7 #include "base/files/file_util.h"
   8 #include "base/files/memory_mapped_file.h"
   9 #include "base/logging.h"
  10 #include "base/message_loop/message_loop.h"
  11 #include "base/path_service.h"
  12 #include "chrome/browser/spellchecker/spellcheck_platform_mac.h"
  13 #include "chrome/browser/spellchecker/spellcheck_service.h"
  14 #include "chrome/common/chrome_paths.h"
  15 #include "chrome/common/spellcheck_common.h"
  16 #include "chrome/common/spellcheck_messages.h"
  17 #include "content/public/browser/browser_thread.h"
  18 #include "content/public/browser/render_process_host.h"
  19 #include "net/base/load_flags.h"
  20 #include "net/url_request/url_fetcher.h"
  21 #include "net/url_request/url_request_context_getter.h"
  22 #include "third_party/hunspell/google/bdict.h"
  23 #include "url/gurl.h"
  24
  25 using content::BrowserThread;
  26
  27 namespace {
  28
  29 // Close the file.
  30 void CloseDictionary(base::File file) {
  31   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
  32   file.Close();
  33 }
  34
  35 // Saves |data| to file at |path|. Returns true on successful save, otherwise
  36 // returns false.
  37 bool SaveDictionaryData(scoped_ptr<std::string> data,
  38                         const base::FilePath& path) {
  39   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
  40
  41   size_t bytes_written =
  42       base::WriteFile(path, data->data(), data->length());
  43   if (bytes_written != data->length()) {
  44     bool success = false;
  45 #if defined(OS_WIN)
  46     base::FilePath dict_dir;
  47     PathService::Get(chrome::DIR_USER_DATA, &dict_dir);
  48     base::FilePath fallback_file_path =
  49         dict_dir.Append(path.BaseName());
  50     bytes_written =
  51         base::WriteFile(fallback_file_path, data->data(), data->length());
  52     if (bytes_written == data->length())
  53       success = true;
  54 #endif
  55
  56     if (!success) {
  57       base::DeleteFile(path, false);
  58       return false;
  59     }
  60   }
  61
  62   return true;
  63 }
  64
  65 }  // namespace
  66
  67 SpellcheckHunspellDictionary::DictionaryFile::DictionaryFile() {
  68  }
  69
  70  SpellcheckHunspellDictionary::DictionaryFile::~DictionaryFile() {
  71   if (file.IsValid()) {
  72     BrowserThread::PostTask(
  73         BrowserThread::FILE,
  74         FROM_HERE,
  75         base::Bind(&CloseDictionary, Passed(&file)));
  76   }
  77 }
  78
  79 SpellcheckHunspellDictionary::DictionaryFile::DictionaryFile(RValue other)
  80     : path(other.object->path),
  81       file(other.object->file.Pass()) {
  82 }
  83
  84 SpellcheckHunspellDictionary::DictionaryFile&
  85 SpellcheckHunspellDictionary::DictionaryFile::operator=(RValue other) {
  86   if (this != other.object) {
  87     path = other.object->path;
  88     file = other.object->file.Pass();
  89   }
  90   return *this;
  91 }
  92
  93 SpellcheckHunspellDictionary::SpellcheckHunspellDictionary(
  94     const std::string& language,
  95     net::URLRequestContextGetter* request_context_getter,
  96     SpellcheckService* spellcheck_service)
  97     : language_(language),
  98       use_platform_spellchecker_(false),
  99       request_context_getter_(request_context_getter),
 100       spellcheck_service_(spellcheck_service),
 101       download_status_(DOWNLOAD_NONE),
 102       weak_ptr_factory_(this) {
 103 }
 104
 105 SpellcheckHunspellDictionary::~SpellcheckHunspellDictionary() {
 106 }
 107
 108 void SpellcheckHunspellDictionary::Load() {
 109   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 110
 111 #if defined(OS_MACOSX)
 112   if (spellcheck_mac::SpellCheckerAvailable() &&
 113       spellcheck_mac::PlatformSupportsLanguage(language_)) {
 114     use_platform_spellchecker_ = true;
 115     spellcheck_mac::SetLanguage(language_);
 116     base::MessageLoop::current()->PostTask(FROM_HERE,
 117         base::Bind(
 118             &SpellcheckHunspellDictionary::InformListenersOfInitialization,
 119             weak_ptr_factory_.GetWeakPtr()));
 120     return;
 121   }
 122 #endif  // OS_MACOSX
 123
 124   BrowserThread::PostTaskAndReplyWithResult(
 125       BrowserThread::FILE,
 126       FROM_HERE,
 127       base::Bind(&InitializeDictionaryLocation, language_),
 128       base::Bind(
 129           &SpellcheckHunspellDictionary::InitializeDictionaryLocationComplete,
 130           weak_ptr_factory_.GetWeakPtr()));
 131 }
 132
 133 void SpellcheckHunspellDictionary::RetryDownloadDictionary(
 134       net::URLRequestContextGetter* request_context_getter) {
 135   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 136   request_context_getter_ = request_context_getter;
 137   DownloadDictionary(GetDictionaryURL());
 138 }
 139
 140 bool SpellcheckHunspellDictionary::IsReady() const {
 141   return GetDictionaryFile().IsValid() || IsUsingPlatformChecker();
 142 }
 143
 144 const base::File& SpellcheckHunspellDictionary::GetDictionaryFile() const {
 145   return dictionary_file_.file;
 146 }
 147
 148 const std::string& SpellcheckHunspellDictionary::GetLanguage() const {
 149   return language_;
 150 }
 151
 152 bool SpellcheckHunspellDictionary::IsUsingPlatformChecker() const {
 153   return use_platform_spellchecker_;
 154 }
 155
 156 void SpellcheckHunspellDictionary::AddObserver(Observer* observer) {
 157   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 158   observers_.AddObserver(observer);
 159 }
 160
 161 void SpellcheckHunspellDictionary::RemoveObserver(Observer* observer) {
 162   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 163   observers_.RemoveObserver(observer);
 164 }
 165
 166 bool SpellcheckHunspellDictionary::IsDownloadInProgress() {
 167   return download_status_ == DOWNLOAD_IN_PROGRESS;
 168 }
 169
 170 bool SpellcheckHunspellDictionary::IsDownloadFailure() {
 171   return download_status_ == DOWNLOAD_FAILED;
 172 }
 173
 174 void SpellcheckHunspellDictionary::OnURLFetchComplete(
 175     const net::URLFetcher* source) {
 176   DCHECK(source);
 177   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 178   scoped_ptr<net::URLFetcher> fetcher_destructor(fetcher_.release());
 179
 180   if ((source->GetResponseCode() / 100) != 2) {
 181     // Initialize will not try to download the file a second time.
 182     InformListenersOfDownloadFailure();
 183     return;
 184   }
 185
 186   // Basic sanity check on the dictionary. There's a small chance of 200 status
 187   // code for a body that represents some form of failure.
 188   scoped_ptr<std::string> data(new std::string);
 189   source->GetResponseAsString(data.get());
 190   if (data->size() < 4 || data->compare(0, 4, "BDic") != 0) {
 191     InformListenersOfDownloadFailure();
 192     return;
 193   }
 194
 195   // To prevent corrupted dictionary data from causing a renderer crash, scan
 196   // the dictionary data and verify it is sane before save it to a file.
 197   // TODO(rlp): Adding metrics to RecordDictionaryCorruptionStats
 198   if (!hunspell::BDict::Verify(data->data(), data->size())) {
 199     // Let PostTaskAndReply caller send to InformListenersOfInitialization
 200     // through SaveDictionaryDataComplete().
 201     SaveDictionaryDataComplete(false);
 202     return;
 203   }
 204
 205   BrowserThread::PostTaskAndReplyWithResult<bool>(
 206       BrowserThread::FILE,
 207       FROM_HERE,
 208       base::Bind(&SaveDictionaryData,
 209                  base::Passed(&data),
 210                  dictionary_file_.path),
 211       base::Bind(&SpellcheckHunspellDictionary::SaveDictionaryDataComplete,
 212                  weak_ptr_factory_.GetWeakPtr()));
 213 }
 214
 215 GURL SpellcheckHunspellDictionary::GetDictionaryURL() {
 216   static const char kDownloadServerUrl[] =
 217       "http://cache.pack.google.com/edgedl/chrome/dict/";
 218   std::string bdict_file = dictionary_file_.path.BaseName().MaybeAsASCII();
 219
 220   DCHECK(!bdict_file.empty());
 221
 222   return GURL(std::string(kDownloadServerUrl) +
 223               base::StringToLowerASCII(bdict_file));
 224 }
 225
 226 void SpellcheckHunspellDictionary::DownloadDictionary(GURL url) {
 227   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 228   DCHECK(request_context_getter_);
 229
 230   download_status_ = DOWNLOAD_IN_PROGRESS;
 231   FOR_EACH_OBSERVER(Observer, observers_, OnHunspellDictionaryDownloadBegin());
 232
 233   fetcher_.reset(net::URLFetcher::Create(url, net::URLFetcher::GET, this));
 234   fetcher_->SetRequestContext(request_context_getter_);
 235   fetcher_->SetLoadFlags(
 236       net::LOAD_DO_NOT_SEND_COOKIES | net::LOAD_DO_NOT_SAVE_COOKIES);
 237   fetcher_->Start();
 238   // Attempt downloading the dictionary only once.
 239   request_context_getter_ = NULL;
 240 }
 241
 242 // The default_dictionary_file can either come from the standard list of
 243 // hunspell dictionaries (determined in InitializeDictionaryLocation), or it
 244 // can be passed in via an extension. In either case, the file is checked for
 245 // existence so that it's not re-downloaded.
 246 // For systemwide installations on Windows, the default directory may not
 247 // have permissions for download. In that case, the alternate directory for
 248 // download is chrome::DIR_USER_DATA.
 249 SpellcheckHunspellDictionary::DictionaryFile
 250 SpellcheckHunspellDictionary::OpenDictionaryFile(const base::FilePath& path) {
 251   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 252   DictionaryFile dictionary;
 253
 254 #if defined(OS_WIN)
 255   // Check if the dictionary exists in the fallback location. If so, use it
 256   // rather than downloading anew.
 257   base::FilePath user_dir;
 258   PathService::Get(chrome::DIR_USER_DATA, &user_dir);
 259   base::FilePath fallback = user_dir.Append(path.BaseName());
 260   if (!base::PathExists(path) && base::PathExists(fallback))
 261     dictionary.path = fallback;
 262   else
 263     dictionary.path = path;
 264 #else
 265   dictionary.path = path;
 266 #endif
 267
 268   // Read the dictionary file and scan its data to check for corruption. The
 269   // scoping closes the memory-mapped file before it is opened or deleted.
 270   bool bdict_is_valid;
 271   {
 272     base::MemoryMappedFile map;
 273     bdict_is_valid =
 274         base::PathExists(dictionary.path) &&
 275         map.Initialize(dictionary.path) &&
 276         hunspell::BDict::Verify(reinterpret_cast<const char*>(map.data()),
 277                                 map.length());
 278   }
 279   if (bdict_is_valid) {
 280     dictionary.file.Initialize(dictionary.path,
 281                                base::File::FLAG_READ | base::File::FLAG_OPEN);
 282   } else {
 283     base::DeleteFile(dictionary.path, false);
 284   }
 285
 286   return dictionary.Pass();
 287 }
 288
 289 // The default place where the spellcheck dictionary resides is
 290 // chrome::DIR_APP_DICTIONARIES.
 291 SpellcheckHunspellDictionary::DictionaryFile
 292 SpellcheckHunspellDictionary::InitializeDictionaryLocation(
 293     const std::string& language) {
 294   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 295
 296   // Initialize the BDICT path. Initialization should be in the FILE thread
 297   // because it checks if there is a "Dictionaries" directory and create it.
 298   base::FilePath dict_dir;
 299   PathService::Get(chrome::DIR_APP_DICTIONARIES, &dict_dir);
 300   base::FilePath dict_path =
 301       chrome::spellcheck_common::GetVersionedFileName(language, dict_dir);
 302
 303   return OpenDictionaryFile(dict_path);
 304 }
 305
 306 void SpellcheckHunspellDictionary::InitializeDictionaryLocationComplete(
 307     DictionaryFile file) {
 308   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 309   dictionary_file_ = file.Pass();
 310
 311   if (!dictionary_file_.file.IsValid()) {
 312
 313     // Notify browser tests that this dictionary is corrupted. Skip downloading
 314     // the dictionary in browser tests.
 315     // TODO(rouslan): Remove this test-only case.
 316     if (spellcheck_service_->SignalStatusEvent(
 317           SpellcheckService::BDICT_CORRUPTED)) {
 318       request_context_getter_ = NULL;
 319     }
 320
 321     if (request_context_getter_) {
 322       // Download from the UI thread to check that |request_context_getter_| is
 323       // still valid.
 324       DownloadDictionary(GetDictionaryURL());
 325       return;
 326     }
 327   }
 328
 329   InformListenersOfInitialization();
 330 }
 331
 332 void SpellcheckHunspellDictionary::SaveDictionaryDataComplete(
 333     bool dictionary_saved) {
 334   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 335
 336   if (dictionary_saved) {
 337     download_status_ = DOWNLOAD_NONE;
 338     FOR_EACH_OBSERVER(Observer,
 339                       observers_,
 340                       OnHunspellDictionaryDownloadSuccess());
 341     Load();
 342   } else {
 343     InformListenersOfDownloadFailure();
 344     InformListenersOfInitialization();
 345   }
 346 }
 347
 348 void SpellcheckHunspellDictionary::InformListenersOfInitialization() {
 349   FOR_EACH_OBSERVER(Observer, observers_, OnHunspellDictionaryInitialized());
 350 }
 351
 352 void SpellcheckHunspellDictionary::InformListenersOfDownloadFailure() {
 353   download_status_ = DOWNLOAD_FAILED;
 354   FOR_EACH_OBSERVER(Observer,
 355                     observers_,
 356                     OnHunspellDictionaryDownloadFailure());
 357 }