diff options
Diffstat (limited to 'gnu-efi/gnu-efi-3.0/lib/sread.c')
| -rw-r--r-- | gnu-efi/gnu-efi-3.0/lib/sread.c | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/gnu-efi/gnu-efi-3.0/lib/sread.c b/gnu-efi/gnu-efi-3.0/lib/sread.c new file mode 100644 index 0000000..888f954 --- /dev/null +++ b/gnu-efi/gnu-efi-3.0/lib/sread.c @@ -0,0 +1,358 @@ +/*++ + +Copyright (c) 1998 Intel Corporation + +Module Name: + + sread.c + +Abstract: + + Simple read file access + + + +Revision History + +--*/ + +#include "lib.h" + +#define SIMPLE_READ_SIGNATURE EFI_SIGNATURE_32('s','r','d','r') +typedef struct _SIMPLE_READ_FILE { + UINTN Signature; + BOOLEAN FreeBuffer; + VOID *Source; + UINTN SourceSize; + EFI_FILE_HANDLE FileHandle; +} SIMPLE_READ_HANDLE; + + + +EFI_STATUS +OpenSimpleReadFile ( + IN BOOLEAN BootPolicy, + IN VOID *SourceBuffer OPTIONAL, + IN UINTN SourceSize, + IN OUT EFI_DEVICE_PATH **FilePath, + OUT EFI_HANDLE *DeviceHandle, + OUT SIMPLE_READ_FILE *SimpleReadHandle + ) +/*++ + +Routine Description: + + Opens a file for (simple) reading. The simple read abstraction + will access the file either from a memory copy, from a file + system interface, or from the load file interface. + +Arguments: + +Returns: + + A handle to access the file + +--*/ +{ + SIMPLE_READ_HANDLE *FHand; + EFI_DEVICE_PATH *UserFilePath; + EFI_DEVICE_PATH *TempFilePath; + EFI_DEVICE_PATH *TempFilePathPtr; + FILEPATH_DEVICE_PATH *FilePathNode; + EFI_FILE_HANDLE FileHandle, LastHandle; + EFI_STATUS Status; + EFI_LOAD_FILE_INTERFACE *LoadFile; + + FHand = NULL; + UserFilePath = *FilePath; + + // + // Allocate a new simple read handle structure + // + + FHand = AllocateZeroPool (sizeof(SIMPLE_READ_HANDLE)); + if (!FHand) { + Status = EFI_OUT_OF_RESOURCES; + goto Done; + } + + *SimpleReadHandle = (SIMPLE_READ_FILE) FHand; + FHand->Signature = SIMPLE_READ_SIGNATURE; + + // + // If the caller passed a copy of the file, then just use it + // + + if (SourceBuffer) { + FHand->Source = SourceBuffer; + FHand->SourceSize = SourceSize; + *DeviceHandle = NULL; + Status = EFI_SUCCESS; + goto Done; + } + + // + // Attempt to access the file via a file system interface + // + + FileHandle = NULL; + Status = uefi_call_wrapper(BS->LocateDevicePath, 3, &FileSystemProtocol, FilePath, DeviceHandle); + if (!EFI_ERROR(Status)) { + FileHandle = LibOpenRoot (*DeviceHandle); + } + + Status = FileHandle ? EFI_SUCCESS : EFI_UNSUPPORTED; + + // + // To access as a filesystem, the filepath should only + // contain filepath components. Follow the filepath nodes + // and find the target file + // + + FilePathNode = (FILEPATH_DEVICE_PATH *) *FilePath; + while (!IsDevicePathEnd(&FilePathNode->Header)) { + + // + // For filesystem access each node should be a filepath component + // + + if (DevicePathType(&FilePathNode->Header) != MEDIA_DEVICE_PATH || + DevicePathSubType(&FilePathNode->Header) != MEDIA_FILEPATH_DP) { + Status = EFI_UNSUPPORTED; + } + + // + // If there's been an error, stop + // + + if (EFI_ERROR(Status)) { + break; + } + + // + // Open this file path node + // + + LastHandle = FileHandle; + FileHandle = NULL; + + Status = uefi_call_wrapper( + LastHandle->Open, + 5, + LastHandle, + &FileHandle, + FilePathNode->PathName, + EFI_FILE_MODE_READ, + 0 + ); + + // + // Close the last node + // + + uefi_call_wrapper(LastHandle->Close, 1, LastHandle); + + // + // Get the next node + // + + FilePathNode = (FILEPATH_DEVICE_PATH *) NextDevicePathNode(&FilePathNode->Header); + } + + // + // If success, return the FHand + // + + if (!EFI_ERROR(Status)) { + ASSERT(FileHandle); + FHand->FileHandle = FileHandle; + goto Done; + } + + // + // Cleanup from filesystem access + // + + if (FileHandle) { + uefi_call_wrapper(FileHandle->Close, 1, FileHandle); + FileHandle = NULL; + *FilePath = UserFilePath; + } + + // + // If the error is something other then unsupported, return it + // + + if (Status != EFI_UNSUPPORTED) { + goto Done; + } + + // + // Attempt to access the file via the load file protocol + // + + Status = LibDevicePathToInterface (&LoadFileProtocol, *FilePath, (VOID*)&LoadFile); + if (!EFI_ERROR(Status)) { + + TempFilePath = DuplicateDevicePath (*FilePath); + + TempFilePathPtr = TempFilePath; + + Status = uefi_call_wrapper(BS->LocateDevicePath, 3, &LoadFileProtocol, &TempFilePath, DeviceHandle); + + FreePool (TempFilePathPtr); + + // + // Determine the size of buffer needed to hold the file + // + + SourceSize = 0; + Status = uefi_call_wrapper( + LoadFile->LoadFile, + 5, + LoadFile, + *FilePath, + BootPolicy, + &SourceSize, + NULL + ); + + // + // We expect a buffer too small error to inform us + // of the buffer size needed + // + + if (Status == EFI_BUFFER_TOO_SMALL) { + SourceBuffer = AllocatePool (SourceSize); + + if (SourceBuffer) { + FHand->FreeBuffer = TRUE; + FHand->Source = SourceBuffer; + FHand->SourceSize = SourceSize; + + Status = uefi_call_wrapper( + LoadFile->LoadFile, + 5, + LoadFile, + *FilePath, + BootPolicy, + &SourceSize, + SourceBuffer + ); + } + } + + // + // If success, return FHand + // + + if (!EFI_ERROR(Status) || Status == EFI_ALREADY_STARTED) { + goto Done; + } + } + + // + // Nothing else to try + // + + DEBUG ((D_LOAD|D_WARN, "OpenSimpleReadFile: Device did not support a known load protocol\n")); + Status = EFI_UNSUPPORTED; + +Done: + + // + // If the file was not accessed, clean up + // + if (EFI_ERROR(Status) && (Status != EFI_ALREADY_STARTED)) { + if (FHand) { + if (FHand->FreeBuffer) { + FreePool (FHand->Source); + } + + FreePool (FHand); + } + } + + return Status; +} + +EFI_STATUS +ReadSimpleReadFile ( + IN SIMPLE_READ_FILE UserHandle, + IN UINTN Offset, + IN OUT UINTN *ReadSize, + OUT VOID *Buffer + ) +{ + UINTN EndPos; + SIMPLE_READ_HANDLE *FHand; + EFI_STATUS Status; + + FHand = UserHandle; + ASSERT (FHand->Signature == SIMPLE_READ_SIGNATURE); + if (FHand->Source) { + + // + // Move data from our local copy of the file + // + + EndPos = Offset + *ReadSize; + if (EndPos > FHand->SourceSize) { + *ReadSize = FHand->SourceSize - Offset; + if (Offset >= FHand->SourceSize) { + *ReadSize = 0; + } + } + + CopyMem (Buffer, (CHAR8 *) FHand->Source + Offset, *ReadSize); + Status = EFI_SUCCESS; + + } else { + + // + // Read data from the file + // + + Status = uefi_call_wrapper(FHand->FileHandle->SetPosition, 2, FHand->FileHandle, Offset); + + if (!EFI_ERROR(Status)) { + Status = uefi_call_wrapper(FHand->FileHandle->Read, 3, FHand->FileHandle, ReadSize, Buffer); + } + } + + return Status; +} + + +VOID +CloseSimpleReadFile ( + IN SIMPLE_READ_FILE UserHandle + ) +{ + SIMPLE_READ_HANDLE *FHand; + + FHand = UserHandle; + ASSERT (FHand->Signature == SIMPLE_READ_SIGNATURE); + + // + // Free any file handle we opened + // + + if (FHand->FileHandle) { + uefi_call_wrapper(FHand->FileHandle->Close, 1, FHand->FileHandle); + } + + // + // If we allocated the Source buffer, free it + // + + if (FHand->FreeBuffer) { + FreePool (FHand->Source); + } + + // + // Done with this simple read file handle + // + + FreePool (FHand); +} |