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Microsoft OS/2 SDK 2.0 05-30-1990

;Thunk Compiler Version 13.25  Jan 10 1990 11:56:04
;File Compiled Fri Apr 13 14:00:54 1990

;Command Line: thunk -y thunks.mif thunks.asm 

;	Static Name Aliases
;

	TITLE	$thunks.asm

	.386

;Error codes taken out of error.h

ERROR_NOMEMORY EQU 8

ERROR_INVALIDPARAM EQU 87

PUBLIC	DEBUG32OUTPUT

CODE32	SEGMENT	DWORD USE32 PUBLIC 'CODE'


EXTRN	DOS32ALLOCMEM:NEAR

EXTRN	DOS32FREEMEM:NEAR

EXTRN	THK32ALIASMEM:NEAR

EXTRN	THK32FREEALIAS:NEAR

EXTRN	THK32ALLOCBLOCK:NEAR

EXTRN	THK32FREEBLOCK:NEAR

EXTRN	THK32HANDLEBOUNDARY:NEAR

EXTRN	THK32HANDLESTRING:NEAR

EXTRN	THK32DEALLOC:NEAR

EXTRN	THK32ALLOCVARLEN:NEAR

CODE32	ENDS
DATA32	SEGMENT	DWORD USE32 PUBLIC 'DATA'

DATA32	ENDS
EXTRN	DEBUGOUTPUT:FAR
CODE16	SEGMENT	WORD USE16 PUBLIC 'CODE'


CODE16	ENDS

;Create a dummy label to trick MASM into correct fixups

CODE16	SEGMENT

T_DEBUGOUTPUT	LABEL FAR

CODE16	ENDS


CODE32	SEGMENT
	ASSUME CS:FLAT,DS:FLAT,ES:FLAT
DEBUG32OUTPUT PROC

	push	ebp
	mov	ebp,esp


	cld			;Assume direction flag clear
	xor	eax,eax
	push	eax		; temp storage for return value
	push	esi
	push	edi
	push	eax		; temp storage 
	push	eax		;Error flag for cleanup
	push	eax		; temp storage for Stack Allocation Flags
	push	eax		; temp storage for BMP Flags
	push	eax		; temp storage for Alias Flags
	push	eax		; temp storage for ptr param #1
;* Compare stack selector against FLAT:R3DSB
;* If the selector is not equal, then don't bump stack.

	mov	ax,ss
	cmp	ax,seg FLAT:DATA32		; standard 32 bit stack?
	jne	short L1		; if not, skip bumping code

;* Bump the stack down if too near 64K boundary.

	mov	eax,esp
	cmp	ax,1024
	jae	short L1
	xor	ax,ax
	mov	esp,eax		; bump the stack down


;Insure that 1 DWORD exists on stack
	push	eax
L1:


; ****> BEGIN Pointer/Structure Section



	mov	esi,[ebp+8]		;fpchText base address

;Pointer fpchText --> pchText
	or	esi,esi
	jz	L2

	mov	[ebp-36],esi
;Handle String Parameters

	push	-32		;Alias flag offset
	push	1		;Flag Mask
	pop	edx
	call	THK32HANDLESTRING
	jc	ERR_DEBUG32OUTPUT			;jmp if too long
	mov	[ebp-36],edi

L2:

; ****> END Pointer/Structure Section

;* Create new call frame, using 16-bit semantics.

	push	es
	push	ebx
	push	ebp			; save ebp
	mov	eax,esp			; save current esp
	push	ss
	push	eax


	mov	dx,ss			; get cpl bits to use as dpl bits
	and	dx,3			; mask off rest of register

	or	dl,4			;Force LDT bit on


	;From Name: fpchText  Type: string
	mov	eax,DWORD PTR [ebp-36]
	or	eax,eax
	jz	short L3			;NULL pointer

	ror	eax,16			; CRMA on structure pointer
	shl	ax,3
	or	al,dl
	rol	eax,16
L3:	push	eax


;* Convert SS:ESP to 16-bit SS:SP.

	mov	eax,esp			; use CRMA on ESP
	ror	eax,16
	shl	ax,3
	or	al,dl
	rol	eax,16

	push	eax			; push new stack pointer
	lss	sp,DWORD PTR [esp]	; ss:sp = 16-bit ptr

;* Jump to 16-bit segment to issue call (so that 16-bit API can RETF).

	jmp	FAR PTR T_DEBUGOUTPUT


INVP_DEBUG32OUTPUT:
	push	87
	pop	eax
	mov	BYTE PTR [ebp-20],1		;Set flag
	jmp	short L4

NOMEM_DEBUG32OUTPUT:
	push	8
	pop	eax

ERR_DEBUG32OUTPUT:
	mov	BYTE PTR [ebp-20],1		;Set flag
	jmp	short L4
R_DEBUGOUTPUT:				; label defining return jmp location


;* Restore 32-bit SS:ESP - it is on top of stack.

	movzx	esp,sp			; make sure that esp is correct
	lss	esp,[esp]
	pop	ebp
	pop	ebx
	pop	es



;Convert Return Code
;SHORT --> LONG
	movsx	eax,ax
L4:
;Functions contain pointers, save return code
	mov	[ebp-4],eax		;Save return code

; ****> BEGIN Pointer/Structure Unpack Section


;Undo Pointer fpchText --> pchText


	mov	esi,[ebp-36]		;fpchText temp address
	or	esi,esi
	jz	L5



	mov	edi,[ebp+8]		;fpchText original address
;Types are identical and no imbedded pointers exist
;This means that we treated the pointer as a buffer
;If temp address == original address then no work required
	cmp	esi,edi
	je	L5
;Handle String Parameters
;Strings are never copied out
	push	-32		;Alloc Flag Offset
	mov	edx,1

	call	THK32DEALLOC


L5:		;No action required

; ****> END Pointer/Structure Unpack Section

;* 32-bit return code.

	lea	esp,[ebp-12]
	pop	edi
	pop	esi
	pop	eax		;Pop saved return code
	leave
	ret				; Remove parameters

DEBUG32OUTPUT endp

CODE32	ENDS

;* 16-bit code to make API call.

CODE16	SEGMENT

	ASSUME CS:CODE16
	.errnz ($ - T_DEBUGOUTPUT)

	call	FAR PTR DEBUGOUTPUT		; call 16-bit version
	jmp	FAR PTR FLAT:R_DEBUGOUTPUT		; jump back

CODE16	ENDS



CODE32	SEGMENT


	ASSUME CS:FLAT,DS:FLAT,SS:FLAT

THK32COPYBLOCK:

; Copy ECX bytes from ESI to EDI
	mov	eax,3
	and	eax,ecx
	shr	ecx,2
	rep movsd
	mov	ecx,eax
	rep movsb

	ret

CODE32	ENDS

	END

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