;-----------------------------------------------------------------------;
; Picture of stack upon entering 32-bit half of WNDPROC callback:
;
;       +-----------------------+
;       | callback parameters   |
;       +-----------------------+
;       | retf to Win3.0        |
;       |                       |
;       +-----------------------+
;       | 32-bit pfn            |
;       |                       |
;       +-----------------------+
;       | iCallbackType         |
;       |                       |
;       +-----------------------+
;       | bp                    | <-- bp/ebp, references up
;       +-----------------------+
;       | si                    |
;       +-----------------------+
;       | di                    |
;       +-----------------------+
;       | ds                    | <-- si/esi, references down if necessary
;       +-----------------------+
;       | THKSPACE16            |       if necessary
;       +-----------------------+
;       | MSGSTRUCT             |       if necessary
;       +-----------------------+
;       | repacked structure(s) |       if necessary
;       +-----------------------+
;       | retf to thunk cleanup |       if necessary
;       |                       |
;       +-----------------------+
;       | ss, sp                | <-- ebx, references saved ss:sp
;       |                       |
;       +-----------------------+
;       | dword alignment pad   |       if necessary
;       +-----------------------+
;-----------------------------------------------------------------------;
;-----------------------------------------------------------------------;
; Picture of stack upon entering 32-bit half of non-WNDPROC callback:
;
;       +-----------------------+
;       | callback parameters   |
;       +-----------------------+
;       | retf to Win3.0        |
;       |                       |
;       +-----------------------+
;       | 32-bit pfn            |
;       |                       |
;       +-----------------------+
;       | iCallbackType         |
;       |                       |
;       +-----------------------+
;       | bp                    | <-- bp/ebp, references up
;       +-----------------------+
;       | si                    |
;       +-----------------------+
;       | di                    |
;       +-----------------------+
;       | ds                    |
;       +-----------------------+
;       | ss, sp                | <-- ebx, references saved ss:sp
;       |                       |
;       +-----------------------+
;       | dword alignment pad   |       if necessary
;       +-----------------------+
;-----------------------------------------------------------------------;

;-----------------------------------------------------------------------;
; ParameterFrame
;
; base
;       The register on which to base addresses.
;
; Define the parameter frame for 16->32 callbacks. This should match
; the picture above.
;-----------------------------------------------------------------------;
ParameterFrame macro base
    base&_pParams           equ     <          [base+14]>
    ;retf                           <dword ptr [base+10]>
    base&_pCallback32       equ     <dword ptr [base+ 6]>
    base&_iCallbackType     equ     <dword ptr [base+ 2]>
    ;bp                             < word ptr [base+ 0]>
    ;si                             < word ptr [base- 2]>
    ;di                             < word ptr [base- 4]>
    ;ds                             < word ptr [base- 6]>
    ;ss,sp                          <dword ptr [base-10]>
    base&_addr_registers    equ     <          [base-10]>
endm

;-----------------------------------------------------------------------;
; LocalFrame
;
; base
;       The register on which to base addresses.
;
; segovr
;       The segment override necessary, if any.
;
; Define the local variable frame. The variables will be accessed via
; the THKSPACE16 structure offsets.  The base&_cleanup label is used
; for discarding the local variables and any extra space used by the
; thunk.
;-----------------------------------------------------------------------;
LocalFrame macro base, segovr
    base&_cleanup equ <dword ptr segovr&[base]>
    base&_space   equ <          segovr&[base - (size THKSPACE16)]>
endm

ParameterFrame  ebp
LocalFrame      esi

ParameterFrame  bp
LocalFrame      bp
LocalFrame      si, ss:
LocalFrame      bx, ss:

;-----------------------------------------------------------------------;
;Equates related to stack frame setup by thunk-compiler generated
;dispatcher.
;-----------------------------------------------------------------------;

ifdef FSAVEALL
offsetThkParams equ 72          ;must match value generated by thunk.exe
else
offsetThkParams equ 40          ;must match value generated by thunk.exe
endif

bp_top  equ     <[bp+offsetThkParams]>
bx_top  equ     <ss:[bx+offsetThkParams]>