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_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(task_runner_, file_handle_,
  72                            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 (!file_util::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
 191 PlatformFileError CreateOrOpenAdapter(
 192     const FilePath& file_path, int file_flags,
 193     PlatformFile* file_handle, bool* created) {
 194   DCHECK(file_handle);
 195   DCHECK(created);
 196   if (!file_util::DirectoryExists(file_path.DirName())) {
 197     // If its parent does not exist, should return NOT_FOUND error.
 198     return PLATFORM_FILE_ERROR_NOT_FOUND;
 199   }
 200   PlatformFileError error = PLATFORM_FILE_OK;
 201   *file_handle = CreatePlatformFile(file_path, file_flags, created, &error);
 202   return error;
 203 }
 204
 205 PlatformFileError CloseAdapter(PlatformFile file_handle) {
 206   if (!ClosePlatformFile(file_handle)) {
 207     return PLATFORM_FILE_ERROR_FAILED;
 208   }
 209   return PLATFORM_FILE_OK;
 210 }
 211
 212 PlatformFileError DeleteAdapter(const FilePath& file_path, bool recursive) {
 213   if (!file_util::PathExists(file_path)) {
 214     return PLATFORM_FILE_ERROR_NOT_FOUND;
 215   }
 216   if (!file_util::Delete(file_path, recursive)) {
 217     if (!recursive && !file_util::IsDirectoryEmpty(file_path)) {
 218       return PLATFORM_FILE_ERROR_NOT_EMPTY;
 219     }
 220     return PLATFORM_FILE_ERROR_FAILED;
 221   }
 222   return PLATFORM_FILE_OK;
 223 }
 224
 225 }  // namespace
 226
 227 // static
 228 bool FileUtilProxy::CreateOrOpen(
 229     TaskRunner* task_runner,
 230     const FilePath& file_path, int file_flags,
 231     const CreateOrOpenCallback& callback) {
 232   return RelayCreateOrOpen(
 233       task_runner,
 234       base::Bind(&CreateOrOpenAdapter, file_path, file_flags),
 235       base::Bind(&CloseAdapter),
 236       callback);
 237 }
 238
 239 // static
 240 bool FileUtilProxy::CreateTemporary(
 241     TaskRunner* task_runner,
 242     int additional_file_flags,
 243     const CreateTemporaryCallback& callback) {
 244   CreateTemporaryHelper* helper = new CreateTemporaryHelper(task_runner);
 245   return task_runner->PostTaskAndReply(
 246       FROM_HERE,
 247       Bind(&CreateTemporaryHelper::RunWork, Unretained(helper),
 248            additional_file_flags),
 249       Bind(&CreateTemporaryHelper::Reply, Owned(helper), callback));
 250 }
 251
 252 // static
 253 bool FileUtilProxy::Close(
 254     TaskRunner* task_runner,
 255     base::PlatformFile file_handle,
 256     const StatusCallback& callback) {
 257   return RelayClose(
 258       task_runner,
 259       base::Bind(&CloseAdapter),
 260       file_handle, callback);
 261 }
 262
 263 // Retrieves the information about a file. It is invalid to pass NULL for the
 264 // callback.
 265 bool FileUtilProxy::GetFileInfo(
 266     TaskRunner* task_runner,
 267     const FilePath& file_path,
 268     const GetFileInfoCallback& callback) {
 269   GetFileInfoHelper* helper = new GetFileInfoHelper;
 270   return task_runner->PostTaskAndReply(
 271       FROM_HERE,
 272       Bind(&GetFileInfoHelper::RunWorkForFilePath,
 273            Unretained(helper), file_path),
 274       Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
 275 }
 276
 277 // static
 278 bool FileUtilProxy::GetFileInfoFromPlatformFile(
 279     TaskRunner* task_runner,
 280     PlatformFile file,
 281     const GetFileInfoCallback& callback) {
 282   GetFileInfoHelper* helper = new GetFileInfoHelper;
 283   return task_runner->PostTaskAndReply(
 284       FROM_HERE,
 285       Bind(&GetFileInfoHelper::RunWorkForPlatformFile,
 286            Unretained(helper), file),
 287       Bind(&GetFileInfoHelper::Reply, Owned(helper), callback));
 288 }
 289
 290 // static
 291 bool FileUtilProxy::Delete(TaskRunner* task_runner,
 292                            const FilePath& file_path,
 293                            bool recursive,
 294                            const StatusCallback& callback) {
 295   return base::PostTaskAndReplyWithResult(
 296       task_runner, FROM_HERE,
 297       Bind(&DeleteAdapter, file_path, recursive),
 298       callback);
 299 }
 300
 301 // static
 302 bool FileUtilProxy::RecursiveDelete(
 303     TaskRunner* task_runner,
 304     const FilePath& file_path,
 305     const StatusCallback& callback) {
 306   return base::PostTaskAndReplyWithResult(
 307       task_runner, FROM_HERE,
 308       Bind(&DeleteAdapter, file_path, true /* recursive */),
 309       callback);
 310 }
 311
 312 // static
 313 bool FileUtilProxy::Read(
 314     TaskRunner* task_runner,
 315     PlatformFile file,
 316     int64 offset,
 317     int bytes_to_read,
 318     const ReadCallback& callback) {
 319   if (bytes_to_read < 0) {
 320     return false;
 321   }
 322   ReadHelper* helper = new ReadHelper(bytes_to_read);
 323   return task_runner->PostTaskAndReply(
 324       FROM_HERE,
 325       Bind(&ReadHelper::RunWork, Unretained(helper), file, offset),
 326       Bind(&ReadHelper::Reply, Owned(helper), callback));
 327 }
 328
 329 // static
 330 bool FileUtilProxy::Write(
 331     TaskRunner* task_runner,
 332     PlatformFile file,
 333     int64 offset,
 334     const char* buffer,
 335     int bytes_to_write,
 336     const WriteCallback& callback) {
 337   if (bytes_to_write <= 0 || buffer == NULL) {
 338     return false;
 339   }
 340   WriteHelper* helper = new WriteHelper(buffer, bytes_to_write);
 341   return task_runner->PostTaskAndReply(
 342       FROM_HERE,
 343       Bind(&WriteHelper::RunWork, Unretained(helper), file, offset),
 344       Bind(&WriteHelper::Reply, Owned(helper), callback));
 345 }
 346
 347 // static
 348 bool FileUtilProxy::Touch(
 349     TaskRunner* task_runner,
 350     PlatformFile file,
 351     const Time& last_access_time,
 352     const Time& last_modified_time,
 353     const StatusCallback& callback) {
 354   return base::PostTaskAndReplyWithResult(
 355       task_runner,
 356       FROM_HERE,
 357       Bind(&TouchPlatformFile, file,
 358            last_access_time, last_modified_time),
 359       Bind(&CallWithTranslatedParameter, callback));
 360 }
 361
 362 // static
 363 bool FileUtilProxy::Touch(
 364     TaskRunner* task_runner,
 365     const FilePath& file_path,
 366     const Time& last_access_time,
 367     const Time& last_modified_time,
 368     const StatusCallback& callback) {
 369   return base::PostTaskAndReplyWithResult(
 370       task_runner,
 371       FROM_HERE,
 372       Bind(&file_util::TouchFile, file_path,
 373            last_access_time, last_modified_time),
 374       Bind(&CallWithTranslatedParameter, callback));
 375 }
 376
 377 // static
 378 bool FileUtilProxy::Truncate(
 379     TaskRunner* task_runner,
 380     PlatformFile file,
 381     int64 length,
 382     const StatusCallback& callback) {
 383   return base::PostTaskAndReplyWithResult(
 384       task_runner,
 385       FROM_HERE,
 386       Bind(&TruncatePlatformFile, file, length),
 387       Bind(&CallWithTranslatedParameter, callback));
 388 }
 389
 390 // static
 391 bool FileUtilProxy::Flush(
 392     TaskRunner* task_runner,
 393     PlatformFile file,
 394     const StatusCallback& callback) {
 395   return base::PostTaskAndReplyWithResult(
 396       task_runner,
 397       FROM_HERE,
 398       Bind(&FlushPlatformFile, file),
 399       Bind(&CallWithTranslatedParameter, callback));
 400 }
 401
 402 // static
 403 bool FileUtilProxy::RelayCreateOrOpen(
 404     TaskRunner* task_runner,
 405     const CreateOrOpenTask& open_task,
 406     const CloseTask& close_task,
 407     const CreateOrOpenCallback& callback) {
 408   CreateOrOpenHelper* helper = new CreateOrOpenHelper(
 409       task_runner, close_task);
 410   return task_runner->PostTaskAndReply(
 411       FROM_HERE,
 412       Bind(&CreateOrOpenHelper::RunWork, Unretained(helper), open_task),
 413       Bind(&CreateOrOpenHelper::Reply, Owned(helper), callback));
 414 }
 415
 416 // static
 417 bool FileUtilProxy::RelayClose(
 418     TaskRunner* task_runner,
 419     const CloseTask& close_task,
 420     PlatformFile file_handle,
 421     const StatusCallback& callback) {
 422   return base::PostTaskAndReplyWithResult(
 423       task_runner, FROM_HERE, Bind(close_task, file_handle), callback);
 424 }
 425
 426 }  // namespace base