MdePkg/Library/UefiDriverEntryPoint/DriverEntryPoint.c

/** @file
  Entry point to a EFI/DXE driver.

Copyright (c) 2006, Intel Corporation<BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

/**
  Unload function that is registered in the LoadImage protocol.  It un-installs
  protocols produced and deallocates pool used by the driver.  Called by the core
  when unloading the driver.

  @param  ImageHandle

  @retval EFI_SUCCESS

**/
EFI_STATUS
EFIAPI
_DriverUnloadHandler (
  EFI_HANDLE ImageHandle
  )
{
  EFI_STATUS  Status;

  //
  // If an UnloadImage() handler is specified, then call it
  //
  Status = ProcessModuleUnloadList (ImageHandle);

  //
  // If the driver specific unload handler does not return an error, then call all of the
  // library destructors.  If the unload handler returned an error, then the driver can not be
  // unloaded, and the library destructors should not be called
  //
  if (!EFI_ERROR (Status)) {
    ProcessLibraryDestructorList (ImageHandle, gST);
  }

  //
  // Return the status from the driver specific unload handler
  //
  return Status;
}

/**
  Enrty point to DXE Driver.

  @param  ImageHandle ImageHandle of the loaded driver.
  @param  SystemTable Pointer to the EFI System Table.

  @retval  EFI_SUCCESS One or more of the drivers returned a success code.
  @retval  !EFI_SUCESS The return status from the last driver entry point in the list.

**/
EFI_STATUS
EFIAPI
_ModuleEntryPoint (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  EFI_STATUS                 Status;
  EFI_LOADED_IMAGE_PROTOCOL  *LoadedImage;

  if (_gUefiDriverRevision != 0) {
    //
    // Make sure that the EFI/UEFI spec revision of the platform is >= EFI/UEFI spec revision of the driver
    //
    if (SystemTable->Hdr.Revision < _gUefiDriverRevision) {
      return EFI_INCOMPATIBLE_VERSION;
    }
  }

  //
  // Call constructor for all libraries
  //
  ProcessLibraryConstructorList (ImageHandle, SystemTable);

  //
  //  Install unload handler...
  //
  if (_gDriverUnloadImageCount != 0) {
    Status = gBS->HandleProtocol (
                    ImageHandle,
                    &gEfiLoadedImageProtocolGuid,
                    (VOID **)&LoadedImage
                    );
    ASSERT_EFI_ERROR (Status);
    LoadedImage->Unload = _DriverUnloadHandler;
  }

  //
  // Call the driver entry point
  //
  Status = ProcessModuleEntryPointList (ImageHandle, SystemTable);

  //
  // If all of the drivers returned errors, then invoke all of the library destructors
  //
  if (EFI_ERROR (Status)) {
    ProcessLibraryDestructorList (ImageHandle, SystemTable);
  }

  //
  // Return the cummalative return status code from all of the driver entry points
  //
  return Status;
}


/**
  Enrty point wrapper of DXE Driver.

  @param  ImageHandle ImageHandle of the loaded driver.
  @param  SystemTable Pointer to the EFI System Table.

  @retval  EFI_SUCCESS One or more of the drivers returned a success code.
  @retval  !EFI_SUCESS The return status from the last driver entry point in the list.

**/
EFI_STATUS
EFIAPI
EfiMain (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  return _ModuleEntryPoint (ImageHandle, SystemTable);
}