GENSHIMSRC

15/08/03

Here is the user documentation that GENSHIMSRC.BAT itself produces:

genshimsrc

	Generate source for a shim DLL and its associated deffile from a supplied deffile

Usage:

	genshimsrc [options] deffile

Where:

	[deffile]     The source deffile

Options:

	--srcpath         the path for the output source file (defaults to CWD)

	--defpath         the path for the output DEF file (defaults to srcpath)

	--name            the name to use for the output files (defaults to shim)

	--version         the version to use for the output DEF file (defaults to 0.0)

	--alignstack      use shims which align the stack to an 8 byte boundary

The following invocation

    genshimsrc.bat --name=xuser-7_0 xuseru.def

would produce two files: xuser-7_0.cia and xuser-7_0{00000000}.def (in CWD). 

The version encoded in the DEF file name can be changed by supplying

the --version option. e.g.

    genshimsrc.bat --name=xuser-7_0 --version=1.0 xuseru.def

would produce two files: xuser-7_0.cia and xuser-7_0{00010000}.def (in CWD). 

The primary purpose of GENSHIMSRC is to allow 'DLL ordinal skew' to be

repaired. It achieves this by generating 'trampoline' functions at the

old ordinal which get linked against import stubs which will be

resolved by the loader at the new ordinal. However the generated files

make it easy for the programmer to inject code into the trampoline if

the need arises by identifying each trampoline with the function it is

derived from. The generated .DEF file also permits a usable IMPORT lib

to be produced for the shim DLL if it is necessary.

As alluded to above, for each entry in the supplied .DEF file

GENSHIMSRC generates an exported (trampoline) function in the .CIA

file and a corresponding entry in the associated .DEF file. Assume the

following entry appears in the supplied .DEF file

AddL__9CObjectIxP7CObject @ 11 NONAME ; CObjectIx::AddL(CObject *)xxxxx

This results in the following source code being generated in the .CIA file

EXPORT_C __NAKED__ int export_at_ordinal_11()

//

// CObjectIx::AddL(CObject *)

//

	{

	asm("B AddL__9CObjectIxP7CObject");

	}

and the following entry being generated in the generated .DEF file

AddL__9CObjectIxP7CObject=export_at_ordinal_11__Fv @ 11 NONAME ; CObjectIx::AddL(CObject *)

These can be incorporated into a buildable project by providing a MMP file which contains:

version			0.0		explicit

target			xuser.dll

targettype		dll

sourcepath		.

source			xuser-7_0.cia

library			xuser{1.0}.lib

systeminclude	..\..\include

deffile			..\..\~\xuser-7_0.def

N.B. There is nothing special about the MMP file.