page ,132
subttl emwin.asm - Initialization and Termination for Windows
;***
;emwin.asm - Initialization and Termination for Windows
;
; Copyright (c) 1987-89, Microsoft Corporation
;
;Purpose:
; Initialization and Termination for Windows
;
; This Module contains Proprietary Information of Microsoft
; Corporation and should be treated as Confidential.
;
;Revision History:
; See emulator.hst
;
;*******************************************************************************
comment !
Windows/DOS interfaces to emulator/8087 functions
Certain emulator/8087 functions are performed by calling __fpmath
with an function code and arguments.
__fpmath general floating point math package interface used
by the emulator/8087 and float calls interfaces. This
is a far routine and must be far called.
entry:
bx = 0 initialize floating point math (program startup)
dx, ax, si input values ignored in WINDOWS emulator
returns:
ax = 0 if successful and using software floating point
1 if successful and using 8087
just terminates process if error
bx = 1 reset (FINIT) - finit ok even under WINDOWS;
typical usage will load control word afterward
so other tasks won't be hindered (as with _fpreset() call)
bx = 2 terminate floating point math (program termination)
bx = 3 set error signal address
dx:ax = segment:offset of user error handler
bx = 4 load user control word
(user should not use FLDCW instruction directly)
ax = user control word value
bx = 5 store user control word
returns:
ax = user control word value
bx = 6 truncate TOS to integer TOS
ax = user control word (only use round mode)
bx = 7 truncate TOS to 32-bit integer in DX:AX
ax = user control word (only use round mode)
bx = 8 store user status word
returns:
ax = user status word value
bx = 9 clear exceptions
bx = 10 return number of stack elements in ax
bx = 11 returns 1 if using 80x87, 0 if not
bx = 12 if ax = 0, turn off extended stack. if ax = 1, turn on e.s.
!
glb <functab>
functab label word
dw initialization ; 0 - initialize emulator/8087
dw reset ; 1 - reset emulator/8087 stack
dw termination ; 2 - terminate emulator/8087
dw setsignal ; 3 - set error signal address
dw loadcontrolword ; 4 - load user control word
dw storecontrolword ; 5 - store user control word
dw truncateTOS ; 6 - truncate TOS to integer TOS
dw truncateTOSto32int ; 7 - truncate TOS to integer in DX:AX
dw storestatusword ; 8 - store user status word
dw clearexceptions ; 9 - clear execeptions
dw NumStack ; 10 - report number of elements in stack
dw ReturnHave8087 ; 11 - report if using coprocessor
dw SetExtendedStack ; 12 - turn on or off extended stack
endfunc label word
SizeJmpTab equ 12
sEnd ecode
sBegin ecode
assumes cs, ecode
assumes ds, edata
public __fpmath
__fpmath proc far
cmp bx, SizeJmpTab
ja RetFPErr
shl bx, 1
push ds ; save DS
mov cx, EMULATOR_DATA
mov ds, cx
call functab[bx]
pop ds ; restore DS
EmuRet:
ret
RetFPErr:
or ax, -1
cwd
jmp EmuRet
__fpmath endp
subttl emwin.asm - Initialization and Termination
page
;*********************************************************************;
; ;
; Initialization and Termination ;
; ;
;*********************************************************************;
wastetime macro
push cx
mov cx,20 ;; wait for a short time
loop $
pop cx
endm
; program initialization
;
; entry dx:ax = task data area (segment and size) for standalone
; si = DOS environment segment for NO87 lookup ???
; DX,AX,SI - ignored in WINDOWS case
; these register inputs are ignored for Windows app
; program-time initialization
pub initialization ; all initialization is done when loaded
ifdef WF
cmp [Installed],0
jnz @F
.286p
push 0
call AllocSelector
mov [wfSel], ax ; Error checking??
mov ax, __WINFLAGS
; int 3
test ax, WF_WIN386
jz wfSlow1
cmp [Have8087], 0
je wfSlow1
or [wfGoFast], 1 ; We can use fast if Enh Mode & FPU
wfSlow1:
@@:
endif
inc [Installed] ; Installed will count number of apps
; using the emulator.
cmp [Have8087], 0 ; check for 8087/80287
je NoInstall87
extrn __FPINSTALL87:near
call __FPINSTALL87 ; set NMI (int 2) for this instance
NoInstall87:
call reset
xor ax, ax
ret
ifdef standalone
mov di,offset BEGstk ; di = base of register stack
mov [BASstk],di ; initialize stack base
mov cx,Reg87Len ; cx = register length
xchg ax,dx ; ax = task data segment size
sub ax,di ; ax = number bytes for stack
cwd ; dx:ax = number of bytes
div cx ; ax = number of entries
mul cx ; ax = number of bytes
add ax,di ; ax = top of stack
sub ax,cx ; Leave room for one on overflow
mov [LIMstk],ax ; set top of stack
endif ;standalone
; check if floating point emulator/8087 already installed (device driver)
; load time initialization
pub LoadTimeInit
push di
push si
push ds
mov ax,EMULATOR_DATA
mov ds,ax
mov ax, __WINFLAGS
and ax, WF_80x87
cmp ax, WF_80x87
jz WinHave87
ifdef only87
jmp loadiniterrorret
endif
jmp WinSet87
pub WinHave87
mov al,1
pub WinSet87
mov [Have8087],al
; real mode emulation and fixup on the fly vector setup
pub initvec
call SaveVectors
call SetVectors
pub loadinitfinish
; finish initialization
pub initfinish
mov [Installed], 0 ; Installed will count number of apps
call reset ; reset (0), FINIT if 8087 present and
; set up default control word
mov ax, 1 ; return non zero result
pub loadiniterrorret
pop ds
pop si
pop di
retf ; far return for dynalink lib entry pt.
;*
;* DLL termination routine.
;*
public WEP
WEP label far
push ds
push ax
push si
push di
mov ax,EMULATOR_DATA
mov ds,ax
call reset
call RestoreVectors
pop di
pop si
pop ax
pop ds
retf 2 ; WEP functions are called with a word paramater.
;------ program termination ----------------------------------------------------
pub termination
call reset ; reset chip for other apps
dec [Installed] ; if Installed is not 0, someone is
jnz termrealdone ; still using the emulator.
ifdef WF
xor ax, ax
xchg ax, [wfSel]
or ax, ax
jz @F
push ax
call FreeSelector
@@:
endif
ifndef only87
cmp [Have8087],0 ; Non zero if 8087 chip exists
je termrealdone
endif ;only87
extrn __FPTERMINATE87:near ; reset NMI (int 2) for this instance
call __FPTERMINATE87
pub termrealdone
ret
subttl emwin.asm - reset and clearexceptions
page
;*********************************************************************;
; ;
; Reset and Clearexceptions ;
; ;
;*********************************************************************;
pub reset
ifndef only87
cmp [Have8087],0 ; Nonzero if 8087 chip exists
je NoFINIT
endif ;only87
fninit
fwait ; Workaround for 80387 bug.
fninit
pub NoFINIT
mov ax, [BASstk]
mov [CURstk], ax ; reset stack to bottom
mov ax, InitControlWord ; setup initial control word
call loadcontrolword
; fall into clearexceptions
pub clearexceptions
xor ax, ax
ifndef only87
cmp al, [Have8087] ; Nonzero if 8087 chip exists
je NoFCLEX
endif ;only87
fclex ; clear exceptions
pub NoFCLEX
ifndef only87
mov [StatusWord], ax ; clear status word
endif ;only87
mov [UserStatusWord], ax ; clear exception status word
ret
subttl emwin.asm - setsignal ---------------------------------
page
;*********************************************************************;
; ;
; Setsignal ;
; ;
;*********************************************************************;
pub setsignal
push ds
mov ds, dx ; set TSKINT to SignalAddress
mov dx, ax
mov ax, 25h*256 + TSKINT
IntDOS
pop ds
ret
pub SaveVectors
mov cx, NUMVEC ; save old vectors under DOS 3
mov ax, 35h*256 + BEGINT ; get vector
mov di, offset oldvec ; di = old vector table
pub getvecs
IntDOS
inc ax
mov [di], bx ; save old vector
mov [di+2], es
add di, 4
loop getvecs
ret
pub SetVectors
ifndef only87
mov dx, offset DStrap ; assume emulator
mov si, offset SOtrap
mov di, offset FWtrap
ifdef WINDOWS
mov ax, __WINFLAGS ; if we are in PMODE & win386 increment all of
and ax, WF_PMODE or WF_WIN386 ; the handler address past the "sti".
cmp ax, WF_PMODE or WF_WIN386
jne NotPmode1
inc dx
inc si
inc di
lab NotPmode1
endif ;WINDOWS
cmp [Have8087], 0 ; are we using 8087 ?
jz SetEmVecs ; no - go ahead and set them
endif ;only87
mov dx, offset DSFixUpOnFly ; set up for fixup-on-the-fly
mov si, offset SOFixUpOnFly
mov di, offset FWFixUpOnFly
ifdef WINDOWS
mov ax, __WINFLAGS ; if we are in PMODE & win386 increment all of
and ax, WF_PMODE or WF_WIN386 ; the handler address past the "sti".
cmp ax, WF_PMODE or WF_WIN386
jne NotPmode2
inc dx
inc si
inc di
lab NotPmode2
endif ;WINDOWS
pub SetEmVecs
push ds
push cs
pop ds
mov ax, 25h*256 + BEGINT
mov cx, 8 ; 8 vectors for DStrap
pub SetDSLoop
IntDOS ; set vector
inc ax ; bump to next one
loop SetDSLoop
mov dx, si ; set Segtrap
IntDOS
inc ax
mov dx, di ; set FWtrap
IntDOS
pop ds ; restore task data area
ret
pub RestoreVectors
mov cx, NUMVEC
mov ax, 25h*256 + BEGINT ; Dos set vector.
mov di, offset oldvec ; di = old vector table
pub ResetVecLoop
push ds
lds dx, [di] ; get old vector value
IntDOS
pop ds
inc ax
add di,4
loop ResetVecLoop
ret
pub NumStack ; returns the number of stack elements in ax
xor dx, dx ; dx will count nonzero elements
ifndef only87
cmp Have8087, 0
je CountEmulatorStack
endif ;only87
sub sp, 14 ; need 14 bytes for fstenv
mov bx, sp
fstenv ss:[bx]
fldcw ss:[bx] ; reset control word
mov ax, ss:[bx+4] ; put tag word in ax
add sp, 14 ; reset stack
mov cx, 8
pub NotEmptyLoop
mov bx, ax
shr ax, 1
shr ax, 1
and bx, 3
cmp bx, 3
je StackEntryEmpty
inc dx ; stack element was not empty
pub StackEntryEmpty
loop NotEmptyLoop
pub CountEmulatorStack
mov ax, CURstk
sub ax, BASstk
mov bl, Reg87Len
div bl
add ax, dx ; add elements on 80x87 stack
ret
ReturnHave8087 proc near
mov al, [Have8087]
cbw
ret
ReturnHave8087 endp
SetExtendedStack proc near
mov [ExtendStack], ax
ret
SetExtendedStack endp
;***
;int far pascal __Win87EmInfo( WinInfoStruct far * p, int cb );
;
;Purpose:
; returns information about win87em.exe to CodeView
;
;Entry:
; WinInfoStruct far * p
; int cb - size of WinInfoStruct
;
;Exit:
; returns non zero if error.
;
;
;Uses:
;
;Exceptions:
;
;*******************************************************************************
cProc __WIN87EMINFO,<PUBLIC,FAR,PLM>,<ds>
parmD p
parmW cb
cBegin
or ax, -1
cmp [cb], size WinInfoStruct
jb WIDone
mov ax, edataBASE
mov es, ax
assumes es, edata
lds bx, [p]
assumes ds, nothing
mov [bx.WI_Version], (major_ver shl 8) + minor_ver
mov [bx.WI_SizeSaveArea], Size80x87Area + edataOFFSET __fptaskdata
mov [bx.WI_WinDataSeg], es
mov [bx.WI_WinCodeSeg], cs
mov al, [Have8087]
cbw
mov [bx.WI_Have80x87], ax
assumes es, nothing
xor ax, ax ; return 0 if no error
mov [bx.WI_Unused], ax
WIDone:
cEnd
;***
;int far pascal __Win87EmSave( void far * p, int cb );
;
;Purpose:
; saves win87em.exe info in p
;
;Entry:
; void far * p - pointer to save area.
; int cb - size of save area.
;
;Exit:
; returns non zero if error.
;
;Uses:
;
;Exceptions:
;
;*******************************************************************************
cProc __WIN87EMSAVE,<PUBLIC,FAR,PLM>,<ds,si,di>
parmD p
parmW cb
cBegin
or ax, -1
cmp [cb], Size80x87Area + edataOFFSET __fptaskdata
jb WSDone
mov ax, edataBASE
mov ds, ax
assumes ds, edata
les di, [p]
assumes es, nothing
cmp [Have8087], 0
je NoSave80x87
fsave es:[di.WSA_Save80x87]
NoSave80x87:
add di, (WSA_SaveEm - WSA_Save80x87)
xor si, si
mov cx, edataOFFSET __fptaskdata
shr cx, 1
rep movsw
jnc NoSaveLastByte
movsb
NoSaveLastByte:
xor ax, ax ; return 0 if no error.
WSDone:
cEnd
;***
;int far pascal __Win87EmRestore( void far * p, int cb );
;
;Purpose:
; retores win87em.exe info from p
;
;Entry:
; void far * p - pointer to save area.
; int cb - size of save area.
;
;Exit:
; returns non zero if error.
;
;Uses:
;
;Exceptions:
;
;*******************************************************************************
cProc __WIN87EMRESTORE,<PUBLIC,FAR,PLM>,<ds,si,di>
parmD p
parmW cb
cBegin
or ax, -1
cmp [cb], Size80x87Area + edataOFFSET __fptaskdata
jb WRDone
mov ax, edataBASE
mov es, ax
assumes es, edata
lds si, [p]
assumes ds, nothing
add si, (WSA_SaveEm - WSA_Save80x87)
xor di, di
mov cx, edataOFFSET __fptaskdata
shr cx, 1
rep movsw
jnc NoRestoreLastByte
movsb
NoRestoreLastByte:
mov si, [OFF_p] ; reset source pointer.
cmp [Have8087], 0
je NoRestore80x87
frstor [si.WSA_Save80x87]
NoRestore80x87:
xor ax, ax ; return 0 if no error.
WRDone:
cEnd
assumes ds, edata
assumes es, nothing