ShellPkg/Include/Library/FileHandleLib.h

   1 /** @file
   2   Provides interface to EFI_FILE_HANDLE functionality.
   3
   4   Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #ifndef _FILE_HANDLE_LIBRARY_HEADER_
  16 #define _FILE_HANDLE_LIBRARY_HEADER_
  17
  18 #include <Protocol/SimpleFileSystem.h>
  19
  20 /// The tag for use in identifying UNICODE files.
  21 /// If the file is UNICODE, the first 16 bits of the file will equal this value.
  22 extern CONST UINT16 gUnicodeFileTag;
  23
  24 /**
  25   This function retrieves information about the file for the handle
  26   specified and stores it in the allocated pool memory.
  27
  28   This function allocates a buffer to store the file's information. It is the
  29   caller's responsibility to free the buffer.
  30
  31   @param[in] FileHandle         The file handle of the file for which information is
  32                                 being requested.
  33
  34   @retval NULL                  Information could not be retrieved.
  35   @retval !NULL                 The information about the file.
  36 **/
  37 EFI_FILE_INFO*
  38 EFIAPI
  39 FileHandleGetInfo (
  40   IN EFI_FILE_HANDLE            FileHandle
  41   );
  42
  43 /**
  44   This function sets the information about the file for the opened handle
  45   specified.
  46
  47   @param[in]  FileHandle        The file handle of the file for which information
  48                                 is being set.
  49
  50   @param[in]  FileInfo          The information to set.
  51
  52   @retval EFI_SUCCESS                   The information was set.
  53   @retval EFI_INVALID_PARAMETER A parameter was out of range or invalid.
  54   @retval EFI_UNSUPPORTED       The FileHandle does not support FileInfo.
  55   @retval EFI_NO_MEDIA                The device has no medium.
  56   @retval EFI_DEVICE_ERROR          The device reported an error.
  57   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  58   @retval EFI_WRITE_PROTECTED     The file or medium is write protected.
  59   @retval EFI_ACCESS_DENIED     The file was opened read only.
  60   @retval EFI_VOLUME_FULL       The volume is full.
  61 **/
  62 EFI_STATUS
  63 EFIAPI
  64 FileHandleSetInfo (
  65   IN EFI_FILE_HANDLE            FileHandle,
  66   IN CONST EFI_FILE_INFO        *FileInfo
  67   );
  68
  69 /**
  70   This function reads information from an opened file.
  71
  72   If FileHandle is not a directory, the function reads the requested number of
  73   bytes from the file at the file's current position and returns them in Buffer.
  74   If the read goes beyond the end of the file, the read length is truncated to the
  75   end of the file. The file's current position is increased by the number of bytes
  76   returned.  If FileHandle is a directory, the function reads the directory entry
  77   at the file's current position and returns the entry in Buffer. If the Buffer
  78   is not large enough to hold the current directory entry, then
  79   EFI_BUFFER_TOO_SMALL is returned and the current file position is not updated.
  80   BufferSize is set to be the size of the buffer needed to read the entry. On
  81   success, the current position is updated to the next directory entry. If there
  82   are no more directory entries, the read returns a zero-length buffer.
  83   EFI_FILE_INFO is the structure returned as the directory entry.
  84
  85   @param[in] FileHandle          The opened file handle.
  86   @param[in, out] BufferSize     On input, the size of buffer in bytes.  On return,
  87                                  the number of bytes written.
  88   @param[out] Buffer             The buffer to put read data into.
  89
  90   @retval EFI_SUCCESS           Data was read.
  91   @retval EFI_NO_MEDIA          The device has no media.
  92   @retval EFI_DEVICE_ERROR      The device reported an error.
  93   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  94   @retval EFI_BUFFER_TO_SMALL   Buffer is too small. ReadSize contains required
  95                                 size.
  96
  97 **/
  98 EFI_STATUS
  99 EFIAPI
 100 FileHandleRead(
 101   IN EFI_FILE_HANDLE            FileHandle,
 102   IN OUT UINTN                  *BufferSize,
 103   OUT VOID                      *Buffer
 104   );
 105
 106 /**
 107   Write data to a file.
 108
 109   This function writes the specified number of bytes to the file at the current
 110   file position. The current file position is advanced the actual number of bytes
 111   written, which is returned in BufferSize. Partial writes only occur when there
 112   has been a data error during the write attempt (such as "volume space full").
 113   The file is automatically grown to hold the data if required. Direct writes to
 114   opened directories are not supported.
 115
 116   @param[in] FileHandle          The opened file for writing.
 117   @param[in, out] BufferSize     On input, the number of bytes in Buffer.  On output,
 118                                  the number of bytes written.
 119   @param[in] Buffer              The buffer containing data to write is stored.
 120
 121   @retval EFI_SUCCESS           Data was written.
 122   @retval EFI_UNSUPPORTED       Writes to an open directory are not supported.
 123   @retval EFI_NO_MEDIA          The device has no media.
 124   @retval EFI_DEVICE_ERROR      The device reported an error.
 125   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
 126   @retval EFI_WRITE_PROTECTED   The device is write-protected.
 127   @retval EFI_ACCESS_DENIED     The file was opened for read only.
 128   @retval EFI_VOLUME_FULL       The volume is full.
 129 **/
 130 EFI_STATUS
 131 EFIAPI
 132 FileHandleWrite(
 133   IN EFI_FILE_HANDLE            FileHandle,
 134   IN OUT UINTN                  *BufferSize,
 135   IN VOID                       *Buffer
 136   );
 137
 138 /**
 139   Close an open file handle.
 140
 141   This function closes a specified file handle. All "dirty" cached file data is
 142   flushed to the device, and the file is closed. In all cases the handle is
 143   closed.
 144
 145   @param[in] FileHandle           The file handle to close.
 146
 147   @retval EFI_SUCCESS             The file handle was closed successfully.
 148 **/
 149 EFI_STATUS
 150 EFIAPI
 151 FileHandleClose (
 152   IN EFI_FILE_HANDLE            FileHandle
 153   );
 154
 155 /**
 156   Delete a file and close the handle.
 157
 158   This function closes and deletes a file. In all cases the file handle is closed.
 159   If the file cannot be deleted, the warning code EFI_WARN_DELETE_FAILURE is
 160   returned, but the handle is still closed.
 161
 162   @param[in] FileHandle             The file handle to delete.
 163
 164   @retval EFI_SUCCESS               The file was closed successfully.
 165   @retval EFI_WARN_DELETE_FAILURE   The handle was closed, but the file was not
 166                                     deleted.
 167   @retval INVALID_PARAMETER         One of the parameters has an invalid value.
 168 **/
 169 EFI_STATUS
 170 EFIAPI
 171 FileHandleDelete (
 172   IN EFI_FILE_HANDLE            FileHandle
 173   );
 174
 175 /**
 176   Set the current position in a file.
 177
 178   This function sets the current file position for the handle to the position
 179   supplied. With the exception of moving to position 0xFFFFFFFFFFFFFFFF, only
 180   absolute positioning is supported, and moving past the end of the file is
 181   allowed (a subsequent write would grow the file). Moving to position
 182   0xFFFFFFFFFFFFFFFF causes the current position to be set to the end of the file.
 183   If FileHandle is a directory, the only position that may be set is zero. This
 184   has the effect of starting the read process of the directory entries over again.
 185
 186   @param[in] FileHandle         The file handle on which the position is being set.
 187   @param[in] Position           The byte position from the begining of the file.
 188
 189   @retval EFI_SUCCESS           The operation completed sucessfully.
 190   @retval EFI_UNSUPPORTED       The request for non-zero is not valid on
 191                                 directories.
 192   @retval INVALID_PARAMETER     One of the parameters has an invalid value.
 193 **/
 194 EFI_STATUS
 195 EFIAPI
 196 FileHandleSetPosition (
 197   IN EFI_FILE_HANDLE    FileHandle,
 198   IN UINT64             Position
 199   );
 200
 201 /**
 202   Gets a file's current position.
 203
 204   This function retrieves the current file position for the file handle. For
 205   directories, the current file position has no meaning outside of the file
 206   system driver. As such, the operation is not supported. An error is returned
 207   if FileHandle is a directory.
 208
 209   @param[in] FileHandle         The open file handle on which to get the position.
 210   @param[out] Position          The byte position from begining of file.
 211
 212   @retval EFI_SUCCESS           The operation completed successfully.
 213   @retval INVALID_PARAMETER     One of the parameters has an invalid value.
 214   @retval EFI_UNSUPPORTED       The request is not valid on directories.
 215 **/
 216 EFI_STATUS
 217 EFIAPI
 218 FileHandleGetPosition (
 219   IN EFI_FILE_HANDLE            FileHandle,
 220   OUT UINT64                    *Position
 221   );
 222 /**
 223   Flushes data on a file.
 224
 225   This function flushes all modified data associated with a file to a device.
 226
 227   @param[in] FileHandle         The file handle on which to flush data.
 228
 229   @retval EFI_SUCCESS           The data was flushed.
 230   @retval EFI_NO_MEDIA          The device has no media.
 231   @retval EFI_DEVICE_ERROR      The device reported an error.
 232   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
 233   @retval EFI_WRITE_PROTECTED   The file or medium is write protected.
 234   @retval EFI_ACCESS_DENIED     The file was opened for read only.
 235 **/
 236 EFI_STATUS
 237 EFIAPI
 238 FileHandleFlush (
 239   IN EFI_FILE_HANDLE            FileHandle
 240   );
 241
 242 /**
 243   Function to determine if a given handle is a directory handle.
 244
 245   If DirHandle is NULL, then ASSERT().
 246
 247   Open the file information on the DirHandle, and verify that the Attribute
 248   includes EFI_FILE_DIRECTORY bit set.
 249
 250   @param[in] DirHandle          The handle to open the file.
 251
 252   @retval EFI_SUCCESS           DirHandle is a directory.
 253   @retval EFI_INVALID_PARAMETER DirHandle did not have EFI_FILE_INFO available.
 254   @retval EFI_NOT_FOUND         DirHandle is not a directory.
 255 **/
 256 EFI_STATUS
 257 EFIAPI
 258 FileHandleIsDirectory (
 259   IN EFI_FILE_HANDLE            DirHandle
 260   );
 261
 262 /**
 263   Retrieves the first file from a directory.
 264
 265   This function opens a directory and gets the first file's information in the
 266   directory. The caller the uses FileHandleFindNextFile() to get other files.  When
 267   complete, the caller is responsible for calling FreePool() on *Buffer.
 268
 269   @param[in] DirHandle          The file handle of the directory to search.
 270   @param[out] Buffer            The pointer to pointer to buffer for file's information.
 271
 272   @retval EFI_SUCCESS           Found the first file.
 273   @retval EFI_NOT_FOUND         Cannot find the directory.
 274   @retval EFI_NO_MEDIA          The device has no media.
 275   @retval EFI_DEVICE_ERROR      The device reported an error.
 276   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
 277   @return Others                The status of FileHandleGetInfo, FileHandleSetPosition,
 278                                 or FileHandleRead.
 279 **/
 280 EFI_STATUS
 281 EFIAPI
 282 FileHandleFindFirstFile (
 283   IN EFI_FILE_HANDLE            DirHandle,
 284   OUT EFI_FILE_INFO             **Buffer
 285   );
 286 /**
 287   Retrieves the next file in a directory.
 288
 289   To use this function, caller must call the FileHandleFindFirstFile() to get the
 290   first file, and then use this function get other files. This function can be
 291   called for several times to get each file's information in the directory. If
 292   the call of FileHandleFindNextFile() got the last file in the directory, the next
 293   call of this function has no file to get. *NoFile will be set to TRUE and the
 294   Buffer memory will be automatically freed.
 295
 296   @param[in] DirHandle          The file handle of the directory.
 297   @param[out] Buffer            The pointer to buffer for file's information.
 298   @param[out] NoFile            The pointer to boolean when last file is found.
 299
 300   @retval EFI_SUCCESS           Found the next file, or reached last file.
 301   @retval EFI_NO_MEDIA          The device has no media.
 302   @retval EFI_DEVICE_ERROR      The device reported an error.
 303   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
 304 **/
 305 EFI_STATUS
 306 EFIAPI
 307 FileHandleFindNextFile(
 308   IN EFI_FILE_HANDLE             DirHandle,
 309   OUT EFI_FILE_INFO              *Buffer,
 310   OUT BOOLEAN                    *NoFile
 311   );
 312
 313 /**
 314   Retrieve the size of a file.
 315
 316   If FileHandle is NULL then ASSERT().
 317   If Size is NULL then ASSERT().
 318
 319   This function extracts the file size info from the FileHandle's EFI_FILE_INFO
 320   data.
 321
 322   @param[in] FileHandle         The file handle from which size is retrieved.
 323   @param[out] Size              The pointer to size.
 324
 325   @retval EFI_SUCCESS           The operation completed successfully.
 326   @retval EFI_DEVICE_ERROR      Cannot access the file.
 327 **/
 328 EFI_STATUS
 329 EFIAPI
 330 FileHandleGetSize (
 331   IN EFI_FILE_HANDLE            FileHandle,
 332   OUT UINT64                    *Size
 333   );
 334
 335 /**
 336   Set the size of a file.
 337
 338   If FileHandle is NULL then ASSERT().
 339
 340   This function changes the file size info from the FileHandle's EFI_FILE_INFO
 341   data.
 342
 343   @param[in] FileHandle         The file handle whose size is to be changed.
 344   @param[in] Size               The new size.
 345
 346   @retval EFI_SUCCESS           The operation completed successfully.
 347   @retval EFI_DEVICE_ERROR      Cannot access the file.
 348 **/
 349 EFI_STATUS
 350 EFIAPI
 351 FileHandleSetSize (
 352   IN EFI_FILE_HANDLE            FileHandle,
 353   IN UINT64                     Size
 354   );
 355
 356 /**
 357   Function to get a full filename given a EFI_FILE_HANDLE somewhere lower on the
 358   directory 'stack'.
 359
 360   @param[in] Handle             Handle to the Directory or File to create path to.
 361   @param[out] FullFileName      Pointer to pointer to generated full file name.  It
 362                                 is the responsibility of the caller to free this memory
 363                                 with a call to FreePool().
 364   @retval EFI_SUCCESS           The operation was successful and FullFileName is valid.
 365   @retval EFI_INVALID_PARAMETER Handle was NULL.
 366   @retval EFI_INVALID_PARAMETER FullFileName was NULL.
 367   @retval EFI_OUT_OF_MEMORY     A memory allocation failed.
 368 **/
 369 EFI_STATUS
 370 EFIAPI
 371 FileHandleGetFileName (
 372   IN CONST EFI_FILE_HANDLE      Handle,
 373   OUT CHAR16                    **FullFileName
 374   );
 375
 376 /**
 377   Function to read a single line (up to but not including the \n) from a file.
 378
 379   If the position upon start is 0, then the Ascii Boolean will be set.  This should be
 380   maintained and not changed for all operations with the same file.
 381
 382   @param[in]       Handle        FileHandle to read from.
 383   @param[in, out]  Buffer        The pointer to buffer to read into.
 384   @param[in, out]  Size          The pointer to number of bytes in Buffer.
 385   @param[in]       Truncate      If the buffer is large enough, this has no effect.
 386                                  If the buffer is is too small and Truncate is TRUE,
 387                                  the line will be truncated.
 388                                  If the buffer is is too small and Truncate is FALSE,
 389                                  then no read will occur.
 390
 391   @param[in, out]  Ascii         Boolean value for indicating whether the file is
 392                                  Ascii (TRUE) or UCS2 (FALSE).
 393
 394   @retval EFI_SUCCESS           The operation was successful.  The line is stored in
 395                                 Buffer.
 396   @retval EFI_INVALID_PARAMETER Handle was NULL.
 397   @retval EFI_INVALID_PARAMETER Size was NULL.
 398   @retval EFI_BUFFER_TOO_SMALL  Size was not large enough to store the line.
 399                                 Size was updated to the minimum space required.
 400   @sa FileHandleRead
 401 **/
 402 EFI_STATUS
 403 EFIAPI
 404 FileHandleReadLine(
 405   IN EFI_FILE_HANDLE            Handle,
 406   IN OUT CHAR16                 *Buffer,
 407   IN OUT UINTN                  *Size,
 408   IN BOOLEAN                    Truncate,
 409   IN OUT BOOLEAN                *Ascii
 410   );
 411
 412 /**
 413   Function to read a single line from a file. The \n is not included in the returned
 414   buffer.  The returned buffer must be callee freed.
 415
 416   If the position upon start is 0, then the Ascii Boolean will be set.  This should be
 417   maintained and not changed for all operations with the same file.
 418
 419   @param[in]       Handle        FileHandle to read from.
 420   @param[in, out]  Ascii         Boolean value for indicating whether the file is
 421                                  Ascii (TRUE) or UCS2 (FALSE).
 422
 423   @return                       The line of text from the file.
 424
 425   @sa FileHandleReadLine
 426 **/
 427 CHAR16*
 428 EFIAPI
 429 FileHandleReturnLine(
 430   IN EFI_FILE_HANDLE            Handle,
 431   IN OUT BOOLEAN                *Ascii
 432   );
 433
 434 /**
 435   Function to write a line of unicode text to a file.
 436
 437   If Handle is NULL, ASSERT.
 438
 439   @param[in]     Handle         FileHandle to write to.
 440   @param[in]     Buffer         Buffer to write, if NULL the function will
 441                                 take no action and return EFI_SUCCESS.
 442
 443   @retval  EFI_SUCCESS          The data was written.
 444   @retval  other                Failure.
 445
 446   @sa FileHandleWrite
 447 **/
 448 EFI_STATUS
 449 EFIAPI
 450 FileHandleWriteLine(
 451   IN EFI_FILE_HANDLE Handle,
 452   IN CHAR16          *Buffer
 453   );
 454
 455 /**
 456   Function to take a formatted argument and print it to a file.
 457
 458   @param[in] Handle   The file handle for the file to write to.
 459   @param[in] Format   The format argument (see printlib for the format specifier).
 460   @param[in] ...      The variable arguments for the format.
 461
 462   @retval EFI_SUCCESS The operation was successful.
 463   @retval other       A return value from FileHandleWriteLine.
 464
 465   @sa FileHandleWriteLine
 466 **/
 467 EFI_STATUS
 468 EFIAPI
 469 FileHandlePrintLine(
 470   IN EFI_FILE_HANDLE  Handle,
 471   IN CONST CHAR16     *Format,
 472   ...
 473   );
 474
 475 /**
 476   Function to determine if a FILE_HANDLE is at the end of the file.
 477
 478   This will NOT work on directories.
 479
 480   If Handle is NULL, then ASSERT().
 481
 482   @param[in] Handle     The file handle.
 483
 484   @retval TRUE          The position is at the end of the file.
 485   @retval FALSE         The position is not at the end of the file.
 486 **/
 487 BOOLEAN
 488 EFIAPI
 489 FileHandleEof(
 490   IN EFI_FILE_HANDLE Handle
 491   );
 492
 493 #endif //_FILE_HANDLE_LIBRARY_HEADER_
 494