base/files/file_util_proxy.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 "base/files/file_util_proxy.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/file_util.h"
  10 #include "base/location.h"
  11 #include "base/message_loop/message_loop_proxy.h"
  12 #include "base/task_runner.h"
  13 #include "base/task_runner_util.h"
  14
  15 namespace base {
  16
  17 namespace {
  18
  19 void CallWithTranslatedParameter(const FileUtilProxy::StatusCallback& callback,
  20                                  bool value) {
  21   DCHECK(!callback.is_null());
  22   callback.Run(value ? PLATFORM_FILE_OK : PLATFORM_FILE_ERROR_FAILED);
  23 }
  24
  25 // Helper classes or routines for individual methods.
  26 class CreateOrOpenHelper {
  27  public:
  28   CreateOrOpenHelper(TaskRunner* task_runner,
  29                      const FileUtilProxy::CloseTask& close_task)
  30       : task_runner_(task_runner),
  31         close_task_(close_task),
  32         file_handle_(kInvalidPlatformFileValue),
  33         created_(false),
  34         error_(PLATFORM_FILE_OK) {}
  35
  36   ~CreateOrOpenHelper() {
  37     if (file_handle_ != kInvalidPlatformFileValue) {
  38       task_runner_->PostTask(
  39           FROM_HERE,
  40           base::Bind(base::IgnoreResult(close_task_), file_handle_));
  41     }
  42   }
  43
  44   void RunWork(const FileUtilProxy::CreateOrOpenTask& task) {
  45     error_ = task.Run(&file_handle_, &created_);
  46   }
  47
  48   void Reply(const FileUtilProxy::CreateOrOpenCallback& callback) {
  49     DCHECK(!callback.is_null());
  50     callback.Run(error_, PassPlatformFile(&file_handle_), created_);
  51   }
  52
  53  private:
  54   scoped_refptr<TaskRunner> task_runner_;
  55   FileUtilProxy::CloseTask close_task_;
  56   PlatformFile file_handle_;
  57   bool created_;
  58   PlatformFileError error_;
  59   DISALLOW_COPY_AND_ASSIGN(CreateOrOpenHelper);
  60 };
  61
  62 class CreateTemporaryHelper {
  63  public:
  64   explicit CreateTemporaryHelper(TaskRunner* task_runner)
  65       : task_runner_(task_runner),
  66         file_handle_(kInvalidPlatformFileValue),
  67         error_(PLATFORM_FILE_OK) {}
  68
  69   ~CreateTemporaryHelper() {
  70     if (file_handle_ != kInvalidPlatformFileValue) {
  71       FileUtilProxy::Close(
  72           task_runner_.get(), file_handle_, FileUtilProxy::StatusCallback());
  73     }
  74   }
  75
  76   void RunWork(int additional_file_flags) {
  77     // TODO(darin): file_util should have a variant of CreateTemporaryFile
  78     // that returns a FilePath and a PlatformFile.
  79     file_util::CreateTemporaryFile(&file_path_);
  80
  81     int file_flags =
  82         PLATFORM_FILE_WRITE |
  83         PLATFORM_FILE_TEMPORARY |
  84         PLATFORM_FILE_CREATE_ALWAYS |
  85         additional_file_flags;
  86
  87     error_ = PLATFORM_FILE_OK;
  88     file_handle_ = CreatePlatformFile(file_path_, file_flags, NULL, &error_);
  89   }
  90
  91   void Reply(const FileUtilProxy::CreateTemporaryCallback& callback) {
  92     DCHECK(!callback.is_null());
  93     callback.Run(error_, PassPlatformFile(&file_handle_), file_path_);
  94   }
  95
  96  private:
  97   scoped_refptr<TaskRunner> task_runner_;
  98   PlatformFile file_handle_;
  99   FilePath file_path_;
 100   PlatformFileError error_;
 101   DISALLOW_COPY_AND_ASSIGN(CreateTemporaryHelper);
 102 };
 103
 104 class GetFileInfoHelper {
 105  public:
 106   GetFileInfoHelper()
 107       : error_(PLATFORM_FILE_OK) {}
 108
 109   void RunWorkForFilePath(const FilePath& file_path) {
 110     if (!PathExists(file_path)) {
 111       error_ = PLATFORM_FILE_ERROR_NOT_FOUND;
 112       return;
 113     }
 114     if (!file_util::GetFileInfo(file_path, &file_info_))
 115       error_ = PLATFORM_FILE_ERROR_FAILED;
 116   }
 117
 118   void RunWorkForPlatformFile(PlatformFile file) {
 119     if (!GetPlatformFileInfo(file, &file_info_))
 120       error_ = PLATFORM_FILE_ERROR_FAILED;
 121   }
 122
 123   void Reply(const FileUtilProxy::GetFileInfoCallback& callback) {
 124     if (!callback.is_null()) {
 125       callback.Run(error_, file_info_);
 126     }
 127   }
 128
 129  private:
 130   PlatformFileError error_;
 131   PlatformFileInfo file_info_;
 132   DISALLOW_COPY_AND_ASSIGN(GetFileInfoHelper);
 133 };
 134
 135 class ReadHelper {
 136  public:
 137   explicit ReadHelper(int bytes_to_read)
 138       : buffer_(new char[bytes_to_read]),
 139         bytes_to_read_(bytes_to_read),
 140         bytes_read_(0) {}
 141
 142   void RunWork(PlatformFile file, int64 offset) {
 143     bytes_read_ = ReadPlatformFile(file, offset, buffer_.get(), bytes_to_read_);
 144   }
 145
 146   void Reply(const FileUtilProxy::ReadCallback& callback) {
 147     if (!callback.is_null()) {
 148       PlatformFileError error =
 149           (bytes_read_ < 0) ? PLATFORM_FILE_ERROR_FAILED : PLATFORM_FILE_OK;
 150       callback.Run(error, buffer_.get(), bytes_read_);
 151     }
 152   }
 153
 154  private:
 155   scoped_ptr<char[]> buffer_;
 156   int bytes_to_read_;
 157   int bytes_read_;
 158   DISALLOW_COPY_AND_ASSIGN(ReadHelper);
 159 };
 160
 161 class WriteHelper {
 162  public:
 163   WriteHelper(const char* buffer, int bytes_to_write)
 164       : buffer_(new char[bytes_to_write]),
 165         bytes_to_write_(bytes_to_write),
 166         bytes_written_(0) {
 167     memcpy(buffer_.get(), buffer, bytes_to_write);
 168   }
 169
 170   void RunWork(PlatformFile file, int64 offset) {
 171     bytes_written_ = WritePlatformFile(file, offset, buffer_.get(),
 172                                        bytes_to_write_);
 173   }
 174
 175   void Reply(const FileUtilProxy::WriteCallback& callback) {
 176     if (!callback.is_null()) {
 177       PlatformFileError error =
 178           (bytes_written_ < 0) ? PLATFORM_FILE_ERROR_FAILED : PLATFORM_FILE_OK;
 179       callback.Run(error, bytes_written_);
 180     }
 181   }
 182
 183  private:
 184   scoped_ptr<char[]> buffer_;
 185   int bytes_to_write_;
 186   int bytes_written_;
 187   DISALLOW_COPY_AND_ASSIGN(WriteHelper);
 188 };
 189
 190 PlatformFileError CreateOrOpenAdapter(
 191     const FilePath& file_path, int file_flags,
 192     PlatformFile* file_handle, bool* created) {
 193   DCHECK(file_handle);
 194   DCHECK(created);
 195   if (!DirectoryExists(file_path.DirName())) {
 196     // If its parent does not exist, should return NOT_FOUND error.
 197     return PLATFORM_FILE_ERROR_NOT_FOUND;
 198   }
 199   PlatformFileError error = PLATFORM_FILE_OK;
 200   *file_handle = CreatePlatformFile(file_path, file_flags, created, &error);
 201   return error;
 202 }
 203
 204 PlatformFileError CloseAdapter(PlatformFile file_handle) {
 205   if (!ClosePlatformFile(file_handle)) {
 206     return PLATFORM_FILE_ERROR_FAILED;
 207   }
 208   return PLATFORM_FILE_OK;
 209 }
 210
 211 PlatformFileError DeleteAdapter(const FilePath& file_path, bool recursive) {
 212   if (!PathExists(file_path)) {
 213     return PLATFORM_FILE_ERROR_NOT_FOUND;
 214   }
 215   if (!base::DeleteFile(file_path, recursive)) {
 216     if (!recursive && !file_util::IsDirectoryEmpty(file_path)) {
 217       return PLATFORM_FILE_ERROR_NOT_EMPTY;
 218     }
 219     return PLATFORM_FILE_ERROR_FAILED;
 220   }
 221   return PLATFORM_FILE_OK;
 222 }
 223
 224 }  // namespace
 225
 226 // static
 227 bool FileUtilProxy::CreateOrOpen(
 228     TaskRunner* task_runner,
 229     const FilePath& file_path, int file_flags,
 230     const CreateOrOpenCallback& callback) {
 231   return RelayCreateOrOpen(
 232       task_runner,
 233       base::Bind(&CreateOrOpenAdapter, file_path, file_flags),
 234       base::Bind(&CloseAdapter),
 235       callback);
 236 }
 237
 238 // static
 239 bool FileUtilProxy::CreateTemporary(
 240     TaskRunner* task_runner,
 241     int additional_file_flags,
 242     const CreateTemporaryCallback& callback) {
 243   CreateTemporaryHelper* helper = new CreateTemporaryHelper(task_runner);
 244   return task_runner->PostTaskAndReply(
 245       FROM_HERE,
 246       Bind(&CreateTemporaryHelper::RunWork, Unretained(helper),
 247            additional_file_flags),
 248       Bind(&CreateTemporaryHelper::Reply, Owned(helper), callback));
 249 }
 250
 251 // static
 252 bool FileUtilProxy::Close(
 253     TaskRunner* task_runner,
 254     base::PlatformFile file_handle,
 255     const StatusCallback& callback) {
 256   return RelayClose(
 257       task_runner,
 258       base::Bind(&CloseAdapter),
 259       file_handle, callback);
 260 }
 261
 262 // Retrieves the information about a file. It is invalid to pass NULL for the
 263 // callback.
 264 bool FileUtilProxy::GetFileInfo(
 265     TaskRunner* task_runner,
 266     const FilePath& file_path,
 267     const GetFileInfoCallback& callback) {
 268   GetFileInfoHelper* helper = new GetFileInfoHelper;
 269   return task_runner->PostTaskAndReply(
 270       FROM_HERE,
 271       Bind(&GetFileInfoHelper::RunWorkForFilePath,
 272            Unretained(helper), file_path),
 273       Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
 274 }
 275
 276 // static
 277 bool FileUtilProxy::GetFileInfoFromPlatformFile(
 278     TaskRunner* task_runner,
 279     PlatformFile file,
 280     const GetFileInfoCallback& callback) {
 281   GetFileInfoHelper* helper = new GetFileInfoHelper;
 282   return task_runner->PostTaskAndReply(
 283       FROM_HERE,
 284       Bind(&GetFileInfoHelper::RunWorkForPlatformFile,
 285            Unretained(helper), file),
 286       Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
 287 }
 288
 289 // static
 290 bool FileUtilProxy::DeleteFile(TaskRunner* task_runner,
 291                                const FilePath& file_path,
 292                                bool recursive,
 293                                const StatusCallback& callback) {
 294   return base::PostTaskAndReplyWithResult(
 295       task_runner, FROM_HERE,
 296       Bind(&DeleteAdapter, file_path, recursive),
 297       callback);
 298 }
 299
 300 // static
 301 bool FileUtilProxy::Read(
 302     TaskRunner* task_runner,
 303     PlatformFile file,
 304     int64 offset,
 305     int bytes_to_read,
 306     const ReadCallback& callback) {
 307   if (bytes_to_read < 0) {
 308     return false;
 309   }
 310   ReadHelper* helper = new ReadHelper(bytes_to_read);
 311   return task_runner->PostTaskAndReply(
 312       FROM_HERE,
 313       Bind(&ReadHelper::RunWork, Unretained(helper), file, offset),
 314       Bind(&ReadHelper::Reply, Owned(helper), callback));
 315 }
 316
 317 // static
 318 bool FileUtilProxy::Write(
 319     TaskRunner* task_runner,
 320     PlatformFile file,
 321     int64 offset,
 322     const char* buffer,
 323     int bytes_to_write,
 324     const WriteCallback& callback) {
 325   if (bytes_to_write <= 0 || buffer == NULL) {
 326     return false;
 327   }
 328   WriteHelper* helper = new WriteHelper(buffer, bytes_to_write);
 329   return task_runner->PostTaskAndReply(
 330       FROM_HERE,
 331       Bind(&WriteHelper::RunWork, Unretained(helper), file, offset),
 332       Bind(&WriteHelper::Reply, Owned(helper), callback));
 333 }
 334
 335 // static
 336 bool FileUtilProxy::Touch(
 337     TaskRunner* task_runner,
 338     PlatformFile file,
 339     const Time& last_access_time,
 340     const Time& last_modified_time,
 341     const StatusCallback& callback) {
 342   return base::PostTaskAndReplyWithResult(
 343       task_runner,
 344       FROM_HERE,
 345       Bind(&TouchPlatformFile, file,
 346            last_access_time, last_modified_time),
 347       Bind(&CallWithTranslatedParameter, callback));
 348 }
 349
 350 // static
 351 bool FileUtilProxy::Touch(
 352     TaskRunner* task_runner,
 353     const FilePath& file_path,
 354     const Time& last_access_time,
 355     const Time& last_modified_time,
 356     const StatusCallback& callback) {
 357   return base::PostTaskAndReplyWithResult(
 358       task_runner,
 359       FROM_HERE,
 360       Bind(&file_util::TouchFile, file_path,
 361            last_access_time, last_modified_time),
 362       Bind(&CallWithTranslatedParameter, callback));
 363 }
 364
 365 // static
 366 bool FileUtilProxy::Truncate(
 367     TaskRunner* task_runner,
 368     PlatformFile file,
 369     int64 length,
 370     const StatusCallback& callback) {
 371   return base::PostTaskAndReplyWithResult(
 372       task_runner,
 373       FROM_HERE,
 374       Bind(&TruncatePlatformFile, file, length),
 375       Bind(&CallWithTranslatedParameter, callback));
 376 }
 377
 378 // static
 379 bool FileUtilProxy::Flush(
 380     TaskRunner* task_runner,
 381     PlatformFile file,
 382     const StatusCallback& callback) {
 383   return base::PostTaskAndReplyWithResult(
 384       task_runner,
 385       FROM_HERE,
 386       Bind(&FlushPlatformFile, file),
 387       Bind(&CallWithTranslatedParameter, callback));
 388 }
 389
 390 // static
 391 bool FileUtilProxy::RelayCreateOrOpen(
 392     TaskRunner* task_runner,
 393     const CreateOrOpenTask& open_task,
 394     const CloseTask& close_task,
 395     const CreateOrOpenCallback& callback) {
 396   CreateOrOpenHelper* helper = new CreateOrOpenHelper(
 397       task_runner, close_task);
 398   return task_runner->PostTaskAndReply(
 399       FROM_HERE,
 400       Bind(&CreateOrOpenHelper::RunWork, Unretained(helper), open_task),
 401       Bind(&CreateOrOpenHelper::Reply, Owned(helper), callback));
 402 }
 403
 404 // static
 405 bool FileUtilProxy::RelayClose(
 406     TaskRunner* task_runner,
 407     const CloseTask& close_task,
 408     PlatformFile file_handle,
 409     const StatusCallback& callback) {
 410   return base::PostTaskAndReplyWithResult(
 411       task_runner, FROM_HERE, Bind(close_task, file_handle), callback);
 412 }
 413
 414 }  // namespace base