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;******************************************************************************

;* Copyright 1991 Advanced Micro Devices, Inc.

;*

;* This software is the property of Advanced Micro Devices, Inc  (AMD)  which

;* specifically  grants the user the right to modify, use and distribute this

;* software provided this notice is not removed or altered.  All other rights

;* are reserved by AMD.

;*

;* AMD MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS

;* SOFTWARE.  IN NO EVENT SHALL AMD BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL

;* DAMAGES IN CONNECTION WITH OR ARISING FROM THE FURNISHING, PERFORMANCE, OR

;* USE OF THIS SOFTWARE.

;*

;* Comments about this software should be directed to udi@amd.com. If access

;* to electronic mail isn't available, send mail to:

;*

;* Advanced Micro Devices, Inc.

;* 29K Support Products

;* Mail Stop 573

;* 5900 E. Ben White Blvd.

;* Austin, TX 78741

;*****************************************************************************

;*       $Id: dosdfe.asm,v 1.1.1.1 2001-05-18 11:27:55 markom Exp $

;*       $Id: @(#)dosdfe.asm    2.5, AMD

;*

IFNDEF  DOS386

        DOSSEG

ENDIF

        INCLUDE udidos.ah

IFDEF   DOS386

rmcode  segment byte public use16

rmcode  ends

rmdata  segment dword public use16

rmdata  ends

pmdata  segment dword public use32

pmdata  ends

pmcode  segment byte public use32

pmcode  ends

dgroup  group   rmdata,pmdata

rmcode  segment

;

; Symbol marking start of real mode code & data,

; used at link time to specify the real mode

; code & data size

;

        public  start_real

start_real label        byte

rmcode  ends

;

; Data that needs to be accessed in both real

; mode and protected mode

;

rmdata  segment

        public code_selector, data_selector, call_prot

        ; these get filled in by protected mode startup code

code_selector  DW ?

data_selector  DW ?

call_prot       DD ?

rmdata  ends

rmdata  segment

        public  TermStruct              ; No auto underscore for Watcom C or HighC386

TermStruct      DOSTerm <>              ; Don't initialize, it will get filled at run time.

        public  UDITerminate            ; need this so we can set up real addr into TermSTruct

rmdata  ends

rmcode  segment

ELSE    ; not DOS386

        PUBLIC  _TermStruct

        .MODEL  LARGE

        .DATA

_TermStruct  DOSTerm 

        .CODE

ENDIF  ; DOS386

UDITerminate    PROC    FAR

;

; Retrieve registers from save area

IFDEF   DOS386

        ASSUME  CS:rmcode

        mov     bx, OFFSET TermStruct   ; in 386 mode, the pointer we pass to TIP

                                        ; has UDITerminate seg = seg(rmcode)

        mov     ax, cs

ELSE    ; not DOS386

        mov     bx, OFFSET _TermStruct

        mov     ax, DGROUP

ENDIF   ; DOS386

        mov     es, ax

        mov     ss, es:[bx].sss

        mov     sp, es:[bx].ssp

        mov     ds, es:[bx].sds

        mov     si, es:[bx].ssi

        mov     di, es:[bx].sdi

        mov     bp, es:[bx].sbp

        mov     ax, es:[bx].retval

        ret                             ; far return because of PROC FAR

UDITerminate ENDP

IFDEF   DOS386

rmcode  ends

pmcode segment

        ASSUME CS:pmcode

        ASSUME DS:dgroup

        public  GetCS

GetCS   PROC NEAR

        mov     ax, cs

        ret

GetCS   ENDP

        public  GetDS

GetDS   PROC NEAR

        mov     ax, ds

        ret

GetDS   ENDP

        public  _exp_call_to

_exp_call_to PROC NEAR

        push    ebp

        mov     ebp, esp

        push    es              ; save at least all regs required by hc386

        push    gs

        push    fs

        push    ds

        push    ebx

        push    esi

        push    edi

        mov     ebx, [ebp+8]

        mov     ax, [ebx+0ah]   ; new ss,ds,etc.

        mov     ecx, [ebx+6]    ; new sp

        sub     ecx, 256        ; back up past TIPname space

        mov     es, ax

        mov     gs, ax

        mov     fs, ax

        mov     ds, ax

        mov     edx, esp

        mov     si, ss  ; save old ss:sp

        mov     ss, ax

        mov     esp, ecx

        ; now on new stack, save old stack

        push    edx

        push    si

        call    fword ptr cs:[ebx]

        ; restore old stack

        pop     si

        pop     edx

        mov     ss,si

        mov     esp,edx

        ; now we are back on original stack

        pop     edi

        pop     esi

        pop     ebx

        pop     ds

        pop     fs

        pop     gs

        pop     es

        pop     ebp

        ret                     ; eax will be the return

_exp_call_to ENDP

pmcode ends

rmdata   segment

;

; Symbol marking end of real mode code & data,

; used at link time to specify the real mode

; code & data size

;

        public  end_real

end_real label  byte

rmdata   ends

ENDIF   ; DOS386

        END