MdeModulePkg/Universal/Disk/UdfDxe/File.c

   1 /** @file
   2   Handle operations in files and directories from UDF/ECMA-167 file systems.
   3
   4   Copyright (C) 2014-2017 Paulo Alcantara <pcacjr@zytor.com>
   5
   6   This program and the accompanying materials are licensed and made available
   7   under the terms and conditions of the BSD License which accompanies this
   8   distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  12   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13 **/
  14
  15 #include "Udf.h"
  16
  17 EFI_FILE_PROTOCOL gUdfFileIoOps = {
  18   EFI_FILE_PROTOCOL_REVISION,
  19   UdfOpen,
  20   UdfClose,
  21   UdfDelete,
  22   UdfRead,
  23   UdfWrite,
  24   UdfGetPosition,
  25   UdfSetPosition,
  26   UdfGetInfo,
  27   UdfSetInfo,
  28   UdfFlush,
  29   NULL,
  30   NULL,
  31   NULL,
  32   NULL
  33 };
  34
  35 #define _ROOT_FILE(_PrivData) (_PrivData)->Root
  36 #define _PARENT_FILE(_PrivData) \
  37   ((_PrivData)->IsRootDirectory ? (_PrivData)->Root : &(_PrivData)->File)
  38 #define _FILE(_PrivData) _PARENT_FILE(_PrivData)
  39
  40 /**
  41   Open the root directory on a volume.
  42
  43   @param  This Protocol instance pointer.
  44   @param  Root Returns an Open file handle for the root directory
  45
  46   @retval EFI_SUCCESS          The device was opened.
  47   @retval EFI_UNSUPPORTED      This volume does not support the file system.
  48   @retval EFI_NO_MEDIA         The device has no media.
  49   @retval EFI_DEVICE_ERROR     The device reported an error.
  50   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
  51   @retval EFI_ACCESS_DENIED    The service denied access to the file.
  52   @retval EFI_OUT_OF_RESOURCES The volume was not opened due to lack of
  53                                resources.
  54
  55 **/
  56 EFI_STATUS
  57 EFIAPI
  58 UdfOpenVolume (
  59   IN   EFI_SIMPLE_FILE_SYSTEM_PROTOCOL  *This,
  60   OUT  EFI_FILE_PROTOCOL                **Root
  61   )
  62 {
  63   EFI_TPL                     OldTpl;
  64   EFI_STATUS                  Status;
  65   PRIVATE_UDF_SIMPLE_FS_DATA  *PrivFsData;
  66   PRIVATE_UDF_FILE_DATA       *PrivFileData;
  67
  68   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
  69
  70   if (This == NULL || Root == NULL) {
  71     Status = EFI_INVALID_PARAMETER;
  72     goto Error_Invalid_Params;
  73   }
  74
  75   PrivFsData = PRIVATE_UDF_SIMPLE_FS_DATA_FROM_THIS (This);
  76
  77   if (PrivFsData->OpenFiles == 0) {
  78     //
  79     // There is no more open files. Read volume information again since it was
  80     // cleaned up on the last UdfClose() call.
  81     //
  82     Status = ReadUdfVolumeInformation (
  83       PrivFsData->BlockIo,
  84       PrivFsData->DiskIo,
  85       &PrivFsData->Volume
  86       );
  87     if (EFI_ERROR (Status)) {
  88       goto Error_Read_Udf_Volume;
  89     }
  90   }
  91
  92   CleanupFileInformation (&PrivFsData->Root);
  93
  94   //
  95   // Find root directory file.
  96   //
  97   Status = FindRootDirectory (
  98     PrivFsData->BlockIo,
  99     PrivFsData->DiskIo,
 100     &PrivFsData->Volume,
 101     &PrivFsData->Root
 102     );
 103   if (EFI_ERROR (Status)) {
 104     goto Error_Find_Root_Dir;
 105   }
 106
 107   PrivFileData =
 108     (PRIVATE_UDF_FILE_DATA *) AllocateZeroPool (sizeof (PRIVATE_UDF_FILE_DATA));
 109   if (PrivFileData == NULL) {
 110     Status = EFI_OUT_OF_RESOURCES;
 111     goto Error_Alloc_Priv_File_Data;
 112   }
 113
 114   PrivFileData->Signature        = PRIVATE_UDF_FILE_DATA_SIGNATURE;
 115   PrivFileData->SimpleFs         = This;
 116   PrivFileData->Root             = &PrivFsData->Root;
 117   PrivFileData->IsRootDirectory  = TRUE;
 118
 119   CopyMem ((VOID *)&PrivFileData->FileIo, (VOID *)&gUdfFileIoOps,
 120            sizeof (EFI_FILE_PROTOCOL));
 121
 122   *Root = &PrivFileData->FileIo;
 123
 124   PrivFsData->OpenFiles++;
 125
 126   gBS->RestoreTPL (OldTpl);
 127
 128   return EFI_SUCCESS;
 129
 130 Error_Alloc_Priv_File_Data:
 131   CleanupFileInformation (&PrivFsData->Root);
 132
 133 Error_Find_Root_Dir:
 134
 135 Error_Read_Udf_Volume:
 136 Error_Invalid_Params:
 137   gBS->RestoreTPL (OldTpl);
 138
 139   return Status;
 140 }
 141
 142 /**
 143   Opens a new file relative to the source file's location.
 144
 145   @param  This       The protocol instance pointer.
 146   @param  NewHandle  Returns File Handle for FileName.
 147   @param  FileName   Null terminated string. "\", ".", and ".." are supported.
 148   @param  OpenMode   Open mode for file.
 149   @param  Attributes Only used for EFI_FILE_MODE_CREATE.
 150
 151   @retval EFI_SUCCESS          The device was opened.
 152   @retval EFI_NOT_FOUND        The specified file could not be found on the
 153                                device.
 154   @retval EFI_NO_MEDIA         The device has no media.
 155   @retval EFI_MEDIA_CHANGED    The media has changed.
 156   @retval EFI_DEVICE_ERROR     The device reported an error.
 157   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 158   @retval EFI_ACCESS_DENIED    The service denied access to the file.
 159   @retval EFI_OUT_OF_RESOURCES The volume was not opened due to lack of
 160                                resources.
 161   @retval EFI_VOLUME_FULL      The volume is full.
 162
 163 **/
 164 EFI_STATUS
 165 EFIAPI
 166 UdfOpen (
 167   IN   EFI_FILE_PROTOCOL  *This,
 168   OUT  EFI_FILE_PROTOCOL  **NewHandle,
 169   IN   CHAR16             *FileName,
 170   IN   UINT64             OpenMode,
 171   IN   UINT64             Attributes
 172   )
 173 {
 174   EFI_TPL                     OldTpl;
 175   EFI_STATUS                  Status;
 176   PRIVATE_UDF_FILE_DATA       *PrivFileData;
 177   PRIVATE_UDF_SIMPLE_FS_DATA  *PrivFsData;
 178   CHAR16                      FilePath[UDF_PATH_LENGTH];
 179   UDF_FILE_INFO               File;
 180   PRIVATE_UDF_FILE_DATA       *NewPrivFileData;
 181   CHAR16                      *TempFileName;
 182
 183   ZeroMem (FilePath, sizeof FilePath);
 184   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 185
 186   if (This == NULL || NewHandle == NULL || FileName == NULL) {
 187     Status = EFI_INVALID_PARAMETER;
 188     goto Error_Invalid_Params;
 189   }
 190
 191   if (OpenMode != EFI_FILE_MODE_READ) {
 192     Status = EFI_WRITE_PROTECTED;
 193     goto Error_Invalid_Params;
 194   }
 195
 196   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 197
 198   PrivFsData = PRIVATE_UDF_SIMPLE_FS_DATA_FROM_THIS (PrivFileData->SimpleFs);
 199
 200   //
 201   // Build full path
 202   //
 203   if (*FileName == L'\\') {
 204     StrCpyS (FilePath, UDF_PATH_LENGTH, FileName);
 205   } else {
 206     StrCpyS (FilePath, UDF_PATH_LENGTH, PrivFileData->AbsoluteFileName);
 207     StrCatS (FilePath, UDF_PATH_LENGTH, L"\\");
 208     StrCatS (FilePath, UDF_PATH_LENGTH, FileName);
 209   }
 210
 211   MangleFileName (FilePath);
 212   if (FilePath[0] == L'\0') {
 213     Status = EFI_NOT_FOUND;
 214     goto Error_Bad_FileName;
 215   }
 216
 217   Status = FindFile (
 218     PrivFsData->BlockIo,
 219     PrivFsData->DiskIo,
 220     &PrivFsData->Volume,
 221     FilePath,
 222     _ROOT_FILE (PrivFileData),
 223     _PARENT_FILE (PrivFileData),
 224     &_PARENT_FILE(PrivFileData)->FileIdentifierDesc->Icb,
 225     &File
 226     );
 227   if (EFI_ERROR (Status)) {
 228     goto Error_Find_File;
 229   }
 230
 231   NewPrivFileData =
 232     (PRIVATE_UDF_FILE_DATA *)AllocateZeroPool (sizeof (PRIVATE_UDF_FILE_DATA));
 233   if (NewPrivFileData == NULL) {
 234     Status = EFI_OUT_OF_RESOURCES;
 235     goto Error_Alloc_New_Priv_File_Data;
 236   }
 237
 238   CopyMem ((VOID *)NewPrivFileData, (VOID *)PrivFileData,
 239            sizeof (PRIVATE_UDF_FILE_DATA));
 240   CopyMem ((VOID *)&NewPrivFileData->File, &File, sizeof (UDF_FILE_INFO));
 241
 242   NewPrivFileData->IsRootDirectory = FALSE;
 243
 244   StrCpyS (NewPrivFileData->AbsoluteFileName, UDF_PATH_LENGTH, FilePath);
 245   FileName = NewPrivFileData->AbsoluteFileName;
 246
 247   while ((TempFileName = StrStr (FileName, L"\\")) != NULL) {
 248     FileName = TempFileName + 1;
 249   }
 250
 251   StrCpyS (NewPrivFileData->FileName, UDF_PATH_LENGTH, FileName);
 252
 253   Status = GetFileSize (
 254     PrivFsData->BlockIo,
 255     PrivFsData->DiskIo,
 256     &PrivFsData->Volume,
 257     &NewPrivFileData->File,
 258     &NewPrivFileData->FileSize
 259     );
 260   if (EFI_ERROR (Status)) {
 261     DEBUG ((
 262       DEBUG_ERROR,
 263       "%a: GetFileSize() fails with status - %r.\n",
 264       __FUNCTION__, Status
 265       ));
 266     goto Error_Get_File_Size;
 267   }
 268
 269   NewPrivFileData->FilePosition = 0;
 270   ZeroMem ((VOID *)&NewPrivFileData->ReadDirInfo,
 271            sizeof (UDF_READ_DIRECTORY_INFO));
 272
 273   *NewHandle = &NewPrivFileData->FileIo;
 274
 275   PrivFsData->OpenFiles++;
 276
 277   gBS->RestoreTPL (OldTpl);
 278
 279   return Status;
 280
 281 Error_Get_File_Size:
 282   FreePool ((VOID *)NewPrivFileData);
 283
 284 Error_Alloc_New_Priv_File_Data:
 285   CleanupFileInformation (&File);
 286
 287 Error_Find_File:
 288 Error_Bad_FileName:
 289 Error_Invalid_Params:
 290   gBS->RestoreTPL (OldTpl);
 291
 292   return Status;
 293 }
 294
 295 /**
 296   Read data from the file.
 297
 298   @param  This       Protocol instance pointer.
 299   @param  BufferSize On input size of buffer, on output amount of data in
 300                      buffer.
 301   @param  Buffer     The buffer in which data is read.
 302
 303   @retval EFI_SUCCESS          Data was read.
 304   @retval EFI_NO_MEDIA         The device has no media.
 305   @retval EFI_DEVICE_ERROR     The device reported an error.
 306   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 307   @retval EFI_BUFFER_TO_SMALL  BufferSize is too small. BufferSize contains
 308                                required size.
 309
 310 **/
 311 EFI_STATUS
 312 EFIAPI
 313 UdfRead (
 314   IN      EFI_FILE_PROTOCOL  *This,
 315   IN OUT  UINTN              *BufferSize,
 316   OUT     VOID               *Buffer
 317   )
 318 {
 319   EFI_TPL                         OldTpl;
 320   EFI_STATUS                      Status;
 321   PRIVATE_UDF_FILE_DATA           *PrivFileData;
 322   PRIVATE_UDF_SIMPLE_FS_DATA      *PrivFsData;
 323   UDF_VOLUME_INFO                 *Volume;
 324   UDF_FILE_INFO                   *Parent;
 325   UDF_READ_DIRECTORY_INFO         *ReadDirInfo;
 326   EFI_BLOCK_IO_PROTOCOL           *BlockIo;
 327   EFI_DISK_IO_PROTOCOL            *DiskIo;
 328   UDF_FILE_INFO                   FoundFile;
 329   UDF_FILE_IDENTIFIER_DESCRIPTOR  *NewFileIdentifierDesc;
 330   VOID                            *NewFileEntryData;
 331   CHAR16                          FileName[UDF_FILENAME_LENGTH];
 332   UINT64                          FileSize;
 333   UINT64                          BufferSizeUint64;
 334
 335   ZeroMem (FileName, sizeof FileName);
 336   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 337
 338   if (This == NULL || BufferSize == NULL || (*BufferSize != 0 &&
 339                                              Buffer == NULL)) {
 340     Status = EFI_INVALID_PARAMETER;
 341     goto Error_Invalid_Params;
 342   }
 343
 344   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 345   PrivFsData = PRIVATE_UDF_SIMPLE_FS_DATA_FROM_THIS (PrivFileData->SimpleFs);
 346
 347   BlockIo                = PrivFsData->BlockIo;
 348   DiskIo                 = PrivFsData->DiskIo;
 349   Volume                 = &PrivFsData->Volume;
 350   ReadDirInfo            = &PrivFileData->ReadDirInfo;
 351   NewFileIdentifierDesc  = NULL;
 352   NewFileEntryData       = NULL;
 353
 354   Parent = _PARENT_FILE (PrivFileData);
 355
 356   Status = EFI_VOLUME_CORRUPTED;
 357
 358   if (IS_FID_NORMAL_FILE (Parent->FileIdentifierDesc)) {
 359     if (PrivFileData->FilePosition > PrivFileData->FileSize) {
 360       //
 361       // File's position is beyond the EOF
 362       //
 363       Status = EFI_DEVICE_ERROR;
 364       goto Error_File_Beyond_The_Eof;
 365     }
 366
 367     if (PrivFileData->FilePosition == PrivFileData->FileSize) {
 368       *BufferSize = 0;
 369       Status = EFI_SUCCESS;
 370       goto Done;
 371     }
 372
 373     BufferSizeUint64 = *BufferSize;
 374
 375     Status = ReadFileData (
 376       BlockIo,
 377       DiskIo,
 378       Volume,
 379       Parent,
 380       PrivFileData->FileSize,
 381       &PrivFileData->FilePosition,
 382       Buffer,
 383       &BufferSizeUint64
 384       );
 385     ASSERT (BufferSizeUint64 <= MAX_UINTN);
 386     *BufferSize = (UINTN)BufferSizeUint64;
 387   } else if (IS_FID_DIRECTORY_FILE (Parent->FileIdentifierDesc)) {
 388     if (ReadDirInfo->FidOffset == 0 && PrivFileData->FilePosition > 0) {
 389       Status = EFI_DEVICE_ERROR;
 390       *BufferSize = 0;
 391       goto Done;
 392     }
 393
 394     for (;;) {
 395       Status = ReadDirectoryEntry (
 396         BlockIo,
 397         DiskIo,
 398         Volume,
 399         &Parent->FileIdentifierDesc->Icb,
 400         Parent->FileEntry,
 401         ReadDirInfo,
 402         &NewFileIdentifierDesc
 403         );
 404       if (EFI_ERROR (Status)) {
 405         if (Status == EFI_DEVICE_ERROR) {
 406           FreePool (ReadDirInfo->DirectoryData);
 407           ZeroMem ((VOID *)ReadDirInfo, sizeof (UDF_READ_DIRECTORY_INFO));
 408
 409           *BufferSize = 0;
 410           Status = EFI_SUCCESS;
 411         }
 412
 413         goto Done;
 414       }
 415       //
 416       // After calling function ReadDirectoryEntry(), if 'NewFileIdentifierDesc'
 417       // is NULL, then the 'Status' must be EFI_OUT_OF_RESOURCES. Hence, if the
 418       // code reaches here, 'NewFileIdentifierDesc' must be not NULL.
 419       //
 420       // The ASSERT here is for addressing a false positive NULL pointer
 421       // dereference issue raised from static analysis.
 422       //
 423       ASSERT (NewFileIdentifierDesc != NULL);
 424
 425       if (!IS_FID_PARENT_FILE (NewFileIdentifierDesc)) {
 426         break;
 427       }
 428
 429       FreePool ((VOID *)NewFileIdentifierDesc);
 430     }
 431
 432     Status = FindFileEntry (
 433       BlockIo,
 434       DiskIo,
 435       Volume,
 436       &NewFileIdentifierDesc->Icb,
 437       &NewFileEntryData
 438       );
 439     if (EFI_ERROR (Status)) {
 440       goto Error_Find_Fe;
 441     }
 442     ASSERT (NewFileEntryData != NULL);
 443
 444     if (FE_ICB_FILE_TYPE (NewFileEntryData) == UdfFileEntrySymlink) {
 445       Status = ResolveSymlink (
 446         BlockIo,
 447         DiskIo,
 448         Volume,
 449         Parent,
 450         NewFileEntryData,
 451         &FoundFile
 452         );
 453       if (EFI_ERROR (Status)) {
 454         goto Error_Resolve_Symlink;
 455       }
 456
 457       FreePool ((VOID *)NewFileEntryData);
 458       NewFileEntryData = FoundFile.FileEntry;
 459
 460       Status = GetFileNameFromFid (NewFileIdentifierDesc, FileName);
 461       if (EFI_ERROR (Status)) {
 462         FreePool ((VOID *)FoundFile.FileIdentifierDesc);
 463         goto Error_Get_FileName;
 464       }
 465
 466       FreePool ((VOID *)NewFileIdentifierDesc);
 467       NewFileIdentifierDesc = FoundFile.FileIdentifierDesc;
 468     } else {
 469       FoundFile.FileIdentifierDesc  = NewFileIdentifierDesc;
 470       FoundFile.FileEntry           = NewFileEntryData;
 471
 472       Status = GetFileNameFromFid (FoundFile.FileIdentifierDesc, FileName);
 473       if (EFI_ERROR (Status)) {
 474         goto Error_Get_FileName;
 475       }
 476     }
 477
 478     Status = GetFileSize (
 479       BlockIo,
 480       DiskIo,
 481       Volume,
 482       &FoundFile,
 483       &FileSize
 484       );
 485     if (EFI_ERROR (Status)) {
 486       goto Error_Get_File_Size;
 487     }
 488
 489     Status = SetFileInfo (
 490       &FoundFile,
 491       FileSize,
 492       FileName,
 493       BufferSize,
 494       Buffer
 495       );
 496     if (EFI_ERROR (Status)) {
 497       goto Error_Set_File_Info;
 498     }
 499
 500     PrivFileData->FilePosition++;
 501     Status = EFI_SUCCESS;
 502   } else if (IS_FID_DELETED_FILE (Parent->FileIdentifierDesc)) {
 503     Status = EFI_DEVICE_ERROR;
 504   }
 505
 506 Error_Set_File_Info:
 507 Error_Get_File_Size:
 508 Error_Get_FileName:
 509 Error_Resolve_Symlink:
 510   if (NewFileEntryData != NULL) {
 511     FreePool (NewFileEntryData);
 512   }
 513
 514 Error_Find_Fe:
 515   if (NewFileIdentifierDesc != NULL) {
 516     FreePool ((VOID *)NewFileIdentifierDesc);
 517   }
 518
 519 Done:
 520 Error_File_Beyond_The_Eof:
 521 Error_Invalid_Params:
 522   gBS->RestoreTPL (OldTpl);
 523
 524   return Status;
 525 }
 526
 527 /**
 528   Close the file handle.
 529
 530   @param  This Protocol instance pointer.
 531
 532   @retval EFI_SUCCESS The file was closed.
 533
 534 **/
 535 EFI_STATUS
 536 EFIAPI
 537 UdfClose (
 538   IN EFI_FILE_PROTOCOL *This
 539   )
 540 {
 541   EFI_TPL                     OldTpl;
 542   EFI_STATUS                  Status;
 543   PRIVATE_UDF_FILE_DATA       *PrivFileData;
 544
 545   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 546
 547   Status = EFI_SUCCESS;
 548
 549   if (This == NULL) {
 550     Status = EFI_INVALID_PARAMETER;
 551     goto Exit;
 552   }
 553
 554   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 555
 556   if (!PrivFileData->IsRootDirectory) {
 557     CleanupFileInformation (&PrivFileData->File);
 558
 559     if (PrivFileData->ReadDirInfo.DirectoryData != NULL) {
 560       FreePool (PrivFileData->ReadDirInfo.DirectoryData);
 561     }
 562   }
 563
 564   FreePool ((VOID *)PrivFileData);
 565
 566 Exit:
 567   gBS->RestoreTPL (OldTpl);
 568
 569   return Status;
 570 }
 571
 572 /**
 573   Close and delete the file handle.
 574
 575   @param  This                     Protocol instance pointer.
 576
 577   @retval EFI_SUCCESS              The file was closed and deleted.
 578   @retval EFI_WARN_DELETE_FAILURE  The handle was closed but the file was not
 579                                    deleted.
 580
 581 **/
 582 EFI_STATUS
 583 EFIAPI
 584 UdfDelete (
 585   IN EFI_FILE_PROTOCOL  *This
 586   )
 587 {
 588   PRIVATE_UDF_FILE_DATA *PrivFileData;
 589
 590   if (This == NULL) {
 591     return EFI_INVALID_PARAMETER;
 592   }
 593
 594   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 595
 596   (VOID)PrivFileData->FileIo.Close(This);
 597
 598   return EFI_WARN_DELETE_FAILURE;
 599 }
 600
 601 /**
 602   Write data to a file.
 603
 604   @param  This       Protocol instance pointer.
 605   @param  BufferSize On input size of buffer, on output amount of data in
 606                      buffer.
 607   @param  Buffer     The buffer in which data to write.
 608
 609   @retval EFI_SUCCESS          Data was written.
 610   @retval EFI_UNSUPPORTED      Writes to Open directory are not supported.
 611   @retval EFI_NO_MEDIA         The device has no media.
 612   @retval EFI_DEVICE_ERROR     The device reported an error.
 613   @retval EFI_DEVICE_ERROR     An attempt was made to write to a deleted file.
 614   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 615   @retval EFI_WRITE_PROTECTED  The device is write protected.
 616   @retval EFI_ACCESS_DENIED    The file was open for read only.
 617   @retval EFI_VOLUME_FULL      The volume is full.
 618
 619 **/
 620 EFI_STATUS
 621 EFIAPI
 622 UdfWrite (
 623   IN      EFI_FILE_PROTOCOL  *This,
 624   IN OUT  UINTN              *BufferSize,
 625   IN      VOID               *Buffer
 626   )
 627 {
 628   return EFI_UNSUPPORTED;
 629 }
 630
 631 /**
 632   Get file's current position.
 633
 634   @param  This      Protocol instance pointer.
 635   @param  Position  Byte position from the start of the file.
 636
 637   @retval EFI_SUCCESS      Position was updated.
 638   @retval EFI_UNSUPPORTED  Seek request for directories is not valid.
 639
 640 **/
 641 EFI_STATUS
 642 EFIAPI
 643 UdfGetPosition (
 644   IN   EFI_FILE_PROTOCOL  *This,
 645   OUT  UINT64             *Position
 646   )
 647 {
 648   PRIVATE_UDF_FILE_DATA *PrivFileData;
 649
 650   if (This == NULL || Position == NULL) {
 651     return EFI_INVALID_PARAMETER;
 652   }
 653
 654   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 655
 656   //
 657   // As per UEFI spec, if the file handle is a directory, then the current file
 658   // position has no meaning and the operation is not supported.
 659   //
 660   if (IS_FID_DIRECTORY_FILE (PrivFileData->File.FileIdentifierDesc)) {
 661     return  EFI_UNSUPPORTED;
 662   }
 663
 664   //
 665   // The file is not a directory. So, return its position.
 666   //
 667   *Position = PrivFileData->FilePosition;
 668
 669   return EFI_SUCCESS;
 670 }
 671
 672 /**
 673   Set file's current position.
 674
 675   @param  This      Protocol instance pointer.
 676   @param  Position  Byte position from the start of the file.
 677
 678   @retval EFI_SUCCESS      Position was updated.
 679   @retval EFI_UNSUPPORTED  Seek request for non-zero is not valid on open.
 680
 681 **/
 682 EFI_STATUS
 683 EFIAPI
 684 UdfSetPosition (
 685   IN EFI_FILE_PROTOCOL  *This,
 686   IN UINT64             Position
 687   )
 688 {
 689   EFI_STATUS                      Status;
 690   PRIVATE_UDF_FILE_DATA           *PrivFileData;
 691   UDF_FILE_IDENTIFIER_DESCRIPTOR  *FileIdentifierDesc;
 692
 693   if (This == NULL) {
 694     return EFI_INVALID_PARAMETER;
 695   }
 696
 697   Status = EFI_UNSUPPORTED;
 698
 699   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 700
 701   FileIdentifierDesc = _FILE (PrivFileData)->FileIdentifierDesc;
 702   ASSERT (FileIdentifierDesc != NULL);
 703   if (IS_FID_DIRECTORY_FILE (FileIdentifierDesc)) {
 704     //
 705     // If the file handle is a directory, the _only_ position that may be set is
 706     // zero. This has no effect of starting the read proccess of the directory
 707     // entries over.
 708     //
 709     if (Position == 0) {
 710       PrivFileData->FilePosition = Position;
 711       PrivFileData->ReadDirInfo.FidOffset = 0;
 712       Status = EFI_SUCCESS;
 713     }
 714   } else if (IS_FID_NORMAL_FILE (FileIdentifierDesc)) {
 715     //
 716     // Seeking to position 0xFFFFFFFFFFFFFFFF causes the current position to be
 717     // set to the EOF.
 718     //
 719     if (Position == 0xFFFFFFFFFFFFFFFF) {
 720       PrivFileData->FilePosition = PrivFileData->FileSize - 1;
 721     } else {
 722       PrivFileData->FilePosition = Position;
 723     }
 724
 725     Status = EFI_SUCCESS;
 726   }
 727
 728   return Status;
 729 }
 730
 731 /**
 732   Get information about a file.
 733
 734   @param  This            Protocol instance pointer.
 735   @param  InformationType Type of information to return in Buffer.
 736   @param  BufferSize      On input size of buffer, on output amount of data in
 737                           buffer.
 738   @param  Buffer          The buffer to return data.
 739
 740   @retval EFI_SUCCESS          Data was returned.
 741   @retval EFI_UNSUPPORTED      InformationType is not supported.
 742   @retval EFI_NO_MEDIA         The device has no media.
 743   @retval EFI_DEVICE_ERROR     The device reported an error.
 744   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 745   @retval EFI_WRITE_PROTECTED  The device is write protected.
 746   @retval EFI_ACCESS_DENIED    The file was open for read only.
 747   @retval EFI_BUFFER_TOO_SMALL Buffer was too small; required size returned in
 748                                BufferSize.
 749
 750 **/
 751 EFI_STATUS
 752 EFIAPI
 753 UdfGetInfo (
 754   IN      EFI_FILE_PROTOCOL  *This,
 755   IN      EFI_GUID           *InformationType,
 756   IN OUT  UINTN              *BufferSize,
 757   OUT     VOID               *Buffer
 758   )
 759 {
 760   EFI_STATUS                  Status;
 761   PRIVATE_UDF_FILE_DATA       *PrivFileData;
 762   PRIVATE_UDF_SIMPLE_FS_DATA  *PrivFsData;
 763   EFI_FILE_SYSTEM_INFO        *FileSystemInfo;
 764   UINTN                       FileSystemInfoLength;
 765   CHAR16                      *String;
 766   UDF_FILE_SET_DESCRIPTOR     *FileSetDesc;
 767   UINTN                       Index;
 768   UINT8                       *OstaCompressed;
 769   UINT8                       CompressionId;
 770   UINT64                      VolumeSize;
 771   UINT64                      FreeSpaceSize;
 772   CHAR16                      VolumeLabel[64];
 773
 774   if (This == NULL || InformationType == NULL || BufferSize == NULL ||
 775       (*BufferSize != 0 && Buffer == NULL)) {
 776     return EFI_INVALID_PARAMETER;
 777   }
 778
 779   PrivFileData = PRIVATE_UDF_FILE_DATA_FROM_THIS (This);
 780
 781   PrivFsData = PRIVATE_UDF_SIMPLE_FS_DATA_FROM_THIS (PrivFileData->SimpleFs);
 782
 783   Status = EFI_UNSUPPORTED;
 784
 785   if (CompareGuid (InformationType, &gEfiFileInfoGuid)) {
 786     Status = SetFileInfo (
 787       _FILE (PrivFileData),
 788       PrivFileData->FileSize,
 789       PrivFileData->FileName,
 790       BufferSize,
 791       Buffer
 792       );
 793   } else if (CompareGuid (InformationType, &gEfiFileSystemInfoGuid)) {
 794     String = VolumeLabel;
 795
 796     FileSetDesc = &PrivFsData->Volume.FileSetDesc;
 797
 798     OstaCompressed = &FileSetDesc->LogicalVolumeIdentifier[0];
 799
 800     CompressionId = OstaCompressed[0];
 801     if (!IS_VALID_COMPRESSION_ID (CompressionId)) {
 802       return EFI_VOLUME_CORRUPTED;
 803     }
 804
 805     for (Index = 1; Index < 128; Index++) {
 806       if (CompressionId == 16) {
 807         *String = *(UINT8 *)(OstaCompressed + Index) << 8;
 808         Index++;
 809       } else {
 810         *String = 0;
 811       }
 812
 813       if (Index < 128) {
 814         *String |= (CHAR16)(*(UINT8 *)(OstaCompressed + Index));
 815       }
 816
 817       //
 818       // Unlike FID Identifiers, Logical Volume Identifier is stored in a
 819       // NULL-terminated OSTA compressed format, so we must check for the NULL
 820       // character.
 821       //
 822       if (*String == L'\0') {
 823         break;
 824       }
 825
 826       String++;
 827     }
 828
 829     *String = L'\0';
 830
 831     FileSystemInfoLength = StrSize (VolumeLabel) +
 832                            sizeof (EFI_FILE_SYSTEM_INFO);
 833     if (*BufferSize < FileSystemInfoLength) {
 834       *BufferSize = FileSystemInfoLength;
 835       return EFI_BUFFER_TOO_SMALL;
 836     }
 837
 838     FileSystemInfo = (EFI_FILE_SYSTEM_INFO *)Buffer;
 839     StrCpyS (FileSystemInfo->VolumeLabel, ARRAY_SIZE (VolumeLabel),
 840              VolumeLabel);
 841     Status = GetVolumeSize (
 842       PrivFsData->BlockIo,
 843       PrivFsData->DiskIo,
 844       &PrivFsData->Volume,
 845       &VolumeSize,
 846       &FreeSpaceSize
 847       );
 848     if (EFI_ERROR (Status)) {
 849       return Status;
 850     }
 851
 852     FileSystemInfo->Size        = FileSystemInfoLength;
 853     FileSystemInfo->ReadOnly    = TRUE;
 854     FileSystemInfo->BlockSize   =
 855       PrivFsData->Volume.LogicalVolDesc.LogicalBlockSize;
 856     FileSystemInfo->VolumeSize  = VolumeSize;
 857     FileSystemInfo->FreeSpace   = FreeSpaceSize;
 858
 859     *BufferSize = FileSystemInfoLength;
 860     Status = EFI_SUCCESS;
 861   }
 862
 863   return Status;
 864 }
 865
 866 /**
 867   Set information about a file.
 868
 869   @param  This            Protocol instance pointer.
 870   @param  InformationType Type of information in Buffer.
 871   @param  BufferSize      Size of buffer.
 872   @param  Buffer          The data to write.
 873
 874   @retval EFI_SUCCESS          Data was set.
 875   @retval EFI_UNSUPPORTED      InformationType is not supported.
 876   @retval EFI_NO_MEDIA         The device has no media.
 877   @retval EFI_DEVICE_ERROR     The device reported an error.
 878   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 879   @retval EFI_WRITE_PROTECTED  The device is write protected.
 880   @retval EFI_ACCESS_DENIED    The file was open for read only.
 881
 882 **/
 883 EFI_STATUS
 884 EFIAPI
 885 UdfSetInfo (
 886   IN EFI_FILE_PROTOCOL  *This,
 887   IN EFI_GUID           *InformationType,
 888   IN UINTN              BufferSize,
 889   IN VOID               *Buffer
 890   )
 891 {
 892   return EFI_WRITE_PROTECTED;
 893 }
 894
 895 /**
 896   Flush data back for the file handle.
 897
 898   @param  This Protocol instance pointer.
 899
 900   @retval EFI_SUCCESS          Data was flushed.
 901   @retval EFI_UNSUPPORTED      Writes to Open directory are not supported.
 902   @retval EFI_NO_MEDIA         The device has no media.
 903   @retval EFI_DEVICE_ERROR     The device reported an error.
 904   @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
 905   @retval EFI_WRITE_PROTECTED  The device is write protected.
 906   @retval EFI_ACCESS_DENIED    The file was open for read only.
 907   @retval EFI_VOLUME_FULL      The volume is full.
 908
 909 **/
 910 EFI_STATUS
 911 EFIAPI
 912 UdfFlush (
 913   IN EFI_FILE_PROTOCOL *This
 914   )
 915 {
 916   return EFI_WRITE_PROTECTED;
 917 }