sbsv1_os/e32toolp/docs/genshimsrc.txt
branchRCL_3
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62:7416fe50a180 73:22bdd8a90cc4
       
     1 GENSHIMSRC
       
     2 15/08/03
       
     3 
       
     4 Here is the user documentation that GENSHIMSRC.BAT itself produces:
       
     5 
       
     6 genshimsrc
       
     7 
       
     8 	Generate source for a shim DLL and its associated deffile from a supplied deffile
       
     9 
       
    10 Usage:
       
    11 	genshimsrc [options] deffile
       
    12 
       
    13 Where:
       
    14 	[deffile]     The source deffile
       
    15 
       
    16 Options:
       
    17 	--srcpath         the path for the output source file (defaults to CWD)
       
    18 	--defpath         the path for the output DEF file (defaults to srcpath)
       
    19 	--name            the name to use for the output files (defaults to shim)
       
    20 	--version         the version to use for the output DEF file (defaults to 0.0)
       
    21 	--alignstack      use shims which align the stack to an 8 byte boundary
       
    22 
       
    23 The following invocation
       
    24 
       
    25     genshimsrc.bat --name=xuser-7_0 xuseru.def
       
    26 
       
    27 would produce two files: xuser-7_0.cia and xuser-7_0{00000000}.def (in CWD). 
       
    28 
       
    29 The version encoded in the DEF file name can be changed by supplying
       
    30 the --version option. e.g.
       
    31 
       
    32     genshimsrc.bat --name=xuser-7_0 --version=1.0 xuseru.def
       
    33 
       
    34 would produce two files: xuser-7_0.cia and xuser-7_0{00010000}.def (in CWD). 
       
    35 
       
    36 The primary purpose of GENSHIMSRC is to allow 'DLL ordinal skew' to be
       
    37 repaired. It achieves this by generating 'trampoline' functions at the
       
    38 old ordinal which get linked against import stubs which will be
       
    39 resolved by the loader at the new ordinal. However the generated files
       
    40 make it easy for the programmer to inject code into the trampoline if
       
    41 the need arises by identifying each trampoline with the function it is
       
    42 derived from. The generated .DEF file also permits a usable IMPORT lib
       
    43 to be produced for the shim DLL if it is necessary.
       
    44 
       
    45 As alluded to above, for each entry in the supplied .DEF file
       
    46 GENSHIMSRC generates an exported (trampoline) function in the .CIA
       
    47 file and a corresponding entry in the associated .DEF file. Assume the
       
    48 following entry appears in the supplied .DEF file
       
    49 
       
    50 AddL__9CObjectIxP7CObject @ 11 NONAME ; CObjectIx::AddL(CObject *)xxxxx
       
    51 
       
    52 This results in the following source code being generated in the .CIA file
       
    53 
       
    54 EXPORT_C __NAKED__ int export_at_ordinal_11()
       
    55 //
       
    56 // CObjectIx::AddL(CObject *)
       
    57 //
       
    58 	{
       
    59 	asm("B AddL__9CObjectIxP7CObject");
       
    60 	}
       
    61 
       
    62 and the following entry being generated in the generated .DEF file
       
    63 
       
    64 AddL__9CObjectIxP7CObject=export_at_ordinal_11__Fv @ 11 NONAME ; CObjectIx::AddL(CObject *)
       
    65 
       
    66 These can be incorporated into a buildable project by providing a MMP file which contains:
       
    67 
       
    68 
       
    69 version			0.0		explicit
       
    70 target			xuser.dll
       
    71 targettype		dll
       
    72 sourcepath		.
       
    73 source			xuser-7_0.cia
       
    74 library			xuser{1.0}.lib
       
    75 systeminclude	..\..\include
       
    76 deffile			..\..\~\xuser-7_0.def
       
    77 
       
    78 
       
    79 N.B. There is nothing special about the MMP file.