audk/Nt32Pkg/Library/PeiNt32PeCoffExtraActionLib/PeiNt32PeCoffExtraActionLib.c

/**@file

Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent

Module Name:

  PeiNt32PeCoffExtraActionLib.c

Abstract:

  Provides services to perform additional actions to relocate and unload
  PE/Coff image for NT32 environment specific purpose such as souce level debug.
  This version only works for PEI phase  


**/
//
// The package level header files this module uses
//
#include <PiPei.h>
#include <WinNtPeim.h>

//
// The protocols, PPI and GUID defintions for this module
//
#include <Ppi/NtThunk.h>

#include <PiPei.h>
#include <Library/PeCoffLib.h>
#include <Library/PeiServicesLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseLib.h>
#include <Library/PeCoffExtraActionLib.h>

//
// Cache of WinNtThunk protocol
//
EFI_WIN_NT_THUNK_PROTOCOL   *mWinNt = NULL;

/**
  The function caches the pointer of the WinNT thunk functions
  It will ASSERT() if NT thunk ppi is not installed.

  @retval EFI_SUCCESS   WinNT thunk protocol is found and cached.

**/
EFI_STATUS
EFIAPI
Nt32PeCoffGetWinNtThunkStucture (
  )
{
	PEI_NT_THUNK_PPI  *NtThunkPpi;
  EFI_STATUS        Status;


  //
  // Locate NtThunkPpi for retrieving standard output handle
  //
  Status = PeiServicesLocatePpi (
              &gPeiNtThunkPpiGuid,
              0,
              NULL,
              (VOID **) &NtThunkPpi
              );

  ASSERT_EFI_ERROR (Status);

  mWinNt  = (EFI_WIN_NT_THUNK_PROTOCOL *) NtThunkPpi->NtThunk ();
  
  return EFI_SUCCESS;
}

/**
  Convert the passed in Ascii string to Unicode.
  
  This function  Convert the passed in Ascii string to Unicode.Optionally return
   the length of the strings..

  @param  AsciiString    Pointer to an AscII string
  @param  StrLen         Length of string

  @return  Pointer to malloc'ed Unicode version of Ascii

**/
CHAR16 *
AsciiToUnicode (
  IN  CHAR8   *Ascii,
  IN  UINTN   *StrLen OPTIONAL
  )
{
  UINTN   Index;
  CHAR16  *Unicode;

  //
  // Allocate a buffer for unicode string
  //
  for (Index = 0; Ascii[Index] != '\0'; Index++)
    ;
  Unicode = mWinNt->HeapAlloc ( mWinNt->GetProcessHeap (),
                                HEAP_ZERO_MEMORY,
                                ((Index + 1) * sizeof (CHAR16))
                               ); 
  if (Unicode == NULL) {
    return NULL;
  }

  for (Index = 0; Ascii[Index] != '\0'; Index++) {
    Unicode[Index] = (CHAR16) Ascii[Index];
  }

  Unicode[Index] = '\0';

  if (StrLen != NULL) {
    *StrLen = Index;
  }

  return Unicode;
}

/**
  Performs additional actions after a PE/COFF image has been loaded and relocated.

  For NT32, this function load symbols to support source level debugging.

  If ImageContext is NULL, then ASSERT().

  @param  ImageContext  Pointer to the image context structure that describes the
                        PE/COFF image that has already been loaded and relocated.

**/
VOID
EFIAPI
PeCoffLoaderRelocateImageExtraAction (
  IN OUT PE_COFF_LOADER_IMAGE_CONTEXT  *ImageContext
  )
{
  VOID              *DllEntryPoint;
  CHAR16            *DllFileName;
  HMODULE           Library;
  UINTN             Index;
  
  ASSERT (ImageContext != NULL);

  if (mWinNt == NULL) {
    Nt32PeCoffGetWinNtThunkStucture ();
  }
	//
  // If we load our own PE COFF images the Windows debugger can not source
  //  level debug our code. If a valid PDB pointer exists usw it to load
  //  the *.dll file as a library using Windows* APIs. This allows 
  //  source level debug. The image is still loaded and relocated
  //  in the Framework memory space like on a real system (by the code above),
  //  but the entry point points into the DLL loaded by the code bellow. 
  //

  DllEntryPoint = NULL;

  //
  // Load the DLL if it's not an EBC image.
  //
  if ((ImageContext->PdbPointer != NULL) &&
      (ImageContext->Machine != EFI_IMAGE_MACHINE_EBC)) {
    //
    // Convert filename from ASCII to Unicode
    //
    DllFileName = AsciiToUnicode (ImageContext->PdbPointer, &Index);

    //
    // Check that we have a valid filename
    //
    if (Index < 5 || DllFileName[Index - 4] != '.') {
      mWinNt->HeapFree (mWinNt->GetProcessHeap (), 0, DllFileName);

      //
      // Never return an error if PeCoffLoaderRelocateImage() succeeded.
      // The image will run, but we just can't source level debug. If we
      // return an error the image will not run.
      //
      return;
    }
    //
    // Replace .PDB with .DLL on the filename
    //
    DllFileName[Index - 3]  = 'D';
    DllFileName[Index - 2]  = 'L';
    DllFileName[Index - 1]  = 'L';

    //
    // Load the .DLL file into the user process's address space for source 
    // level debug
    //
    Library = mWinNt->LoadLibraryEx  (DllFileName, NULL, DONT_RESOLVE_DLL_REFERENCES);
    if (Library != NULL) {
      //
      // InitializeDriver is the entry point we put in all our EFI DLL's. The
      // DONT_RESOLVE_DLL_REFERENCES argument to LoadLIbraryEx() suppresses the 
      // normal DLL entry point of DllMain, and prevents other modules that are
      // referenced in side the DllFileName from being loaded. There is no error 
      // checking as the we can point to the PE32 image loaded by Tiano. This 
      // step is only needed for source level debugging
      //
      DllEntryPoint = (VOID *) (UINTN) mWinNt->GetProcAddress (Library, "InitializeDriver");

    }

    if ((Library != NULL) && (DllEntryPoint != NULL)) {
      ImageContext->EntryPoint  = (EFI_PHYSICAL_ADDRESS) (UINTN) DllEntryPoint;
      DEBUG ((EFI_D_INFO, "LoadLibraryEx (%s,\n               NULL, DONT_RESOLVE_DLL_REFERENCES)\n", DllFileName));
     } else {
      DEBUG ((EFI_D_ERROR, "WARNING: No source level debug %s. \n", DllFileName));
    }

    mWinNt->HeapFree (mWinNt->GetProcessHeap (), 0, DllFileName);
  }

  //
  // Never return an error if PeCoffLoaderRelocateImage() succeeded.
  // The image will run, but we just can't source level debug. If we
  // return an error the image will not run.
  //
  return;
}  

/**
  Performs additional actions just before a PE/COFF image is unloaded.  Any resources
  that were allocated by PeCoffLoaderRelocateImageExtraAction() must be freed.
  
  For NT32, this function unloads symbols for source level debugging.

  If ImageContext is NULL, then ASSERT().
  
  @param  ImageContext  Pointer to the image context structure that describes the
                        PE/COFF image that is being unloaded.

**/
VOID
EFIAPI
PeCoffLoaderUnloadImageExtraAction (
  IN OUT PE_COFF_LOADER_IMAGE_CONTEXT  *ImageContext
  )
{
  ASSERT (ImageContext != NULL);
}