Function GetNvramVariable

rEFIt_UEFI/Platform/Nvram.cpp:98–137

Reads and returns value of NVRAM variable. */

/** Reads and returns value of NVRAM variable. */
VOID *GetNvramVariable(
	IN      CONST CHAR16   *VariableName,
	IN      EFI_GUID *VendorGuid,
	OUT     UINT32   *Attributes    OPTIONAL,
	OUT     UINTN    *DataSize      OPTIONAL)
{
  EFI_STATUS Status;
  VOID       *Data       = NULL;
  //
  // Pass in a zero size buffer to find the required buffer size.
  //
  UINTN      IntDataSize = 0;
  
  Status = gRT->GetVariable (VariableName, VendorGuid, Attributes, &IntDataSize, NULL);
  if (IntDataSize == 0) {
    return NULL;
  }

  if (Status == EFI_BUFFER_TOO_SMALL) {
    //
    // Allocate the buffer to return
    //
    Data = (__typeof__(Data))AllocateZeroPool(IntDataSize + 1);
    if (Data != NULL) {
      //
      // Read variable into the allocated buffer.
      //
      Status = gRT->GetVariable (VariableName, VendorGuid, Attributes, &IntDataSize, Data);
      if (EFI_ERROR(Status)) {
        FreePool(Data);
        IntDataSize = 0;
        Data = NULL;
      }
    }
  }
  if (DataSize != NULL) {
    *DataSize = IntDataSize;
  }
  return Data;
}

/** Reads and returns value of NVRAM variable. */
XString8 GetNvramVariableAsXString8(