173 lines
4.3 KiB
NASM
173 lines
4.3 KiB
NASM
page ,132
|
|
;----------------------------Module-Header------------------------------;
|
|
; Module Name: FLAT.ASM
|
|
;
|
|
; init/term routines for using flat pointers
|
|
;
|
|
; LocalAlloc should go through here!
|
|
;
|
|
;-----------------------------------------------------------------------;
|
|
.286
|
|
?PLM=1
|
|
?WIN=0
|
|
.xlist
|
|
include cmacros.inc
|
|
.list
|
|
|
|
;--------------------------------------------------------------------------;
|
|
;--------------------------------------------------------------------------;
|
|
|
|
sBegin Data
|
|
public flatBase
|
|
public flatSel
|
|
flatSel dw 0
|
|
flatBase dd 0
|
|
KernelLocalAlloc dd 0
|
|
sEnd
|
|
|
|
ifndef SEGNAME
|
|
SEGNAME equ <_TEXT>
|
|
endif
|
|
|
|
createSeg %SEGNAME, CodeSeg, word, public, CODE
|
|
|
|
sBegin CodeSeg
|
|
assumes cs,CodeSeg
|
|
assumes ds,Data
|
|
assumes es,nothing
|
|
|
|
externFP GetSelectorBase ; in KERNEL
|
|
externFP SetSelectorBase ; in KERNEL
|
|
externFP GetSelectorLimit ; in KERNEL
|
|
externFP SetSelectorLimit ; in KERNEL
|
|
externFP GlobalWire ; in KERNEL
|
|
externFP GlobalUnwire ; in KERNEL
|
|
externFP GlobalFix ; in KERNEL
|
|
externFP GlobalUnfix ; in KERNEL
|
|
; externFP KernelLocalAlloc ; in KERNEL
|
|
|
|
externFP GetProcAddress ; in KERNEL
|
|
externFP GetModuleHandle ; in KERNEL
|
|
|
|
externFP AllocSelector ; in KERNEL
|
|
externFP FreeSelector ; in KERNEL
|
|
|
|
;--------------------------------------------------------------------------;
|
|
;
|
|
; FlatInit
|
|
;
|
|
;--------------------------------------------------------------------------;
|
|
|
|
cProc FlatInit, <FAR, PUBLIC, PASCAL>
|
|
cBegin
|
|
; cCall GlobalWire, <ds>
|
|
cCall GlobalFix, <ds>
|
|
|
|
cCall AllocSelector,<ds>
|
|
mov [flatSel],ax
|
|
|
|
mov bx,ax
|
|
mov ax,0008h ; DPMI Set Limit
|
|
mov cx,-1
|
|
mov dx,-1
|
|
int 31h
|
|
|
|
; cCall SetSelectorLimit,<ax,-1,-1>
|
|
|
|
cCall GetSelectorBase, <ds>
|
|
mov word ptr flatBase[0],ax
|
|
mov word ptr flatBase[2],dx
|
|
cEnd
|
|
|
|
;--------------------------------------------------------------------------;
|
|
;
|
|
; FlatTerm
|
|
;
|
|
;--------------------------------------------------------------------------;
|
|
|
|
cProc FlatTerm, <FAR, PUBLIC, PASCAL>
|
|
cBegin
|
|
cCall SetSelectorLimit,<[flatSel],0,0>
|
|
cCall FreeSelector,<[flatSel]>
|
|
|
|
; cCall GlobalUnwire, <ds>
|
|
cCall GlobalUnfix, <ds>
|
|
mov word ptr [flatBase][0],0
|
|
mov word ptr [flatBase][2],0
|
|
mov [flatSel],0
|
|
cEnd
|
|
|
|
;--------------------------------------------------------------------------;
|
|
;
|
|
; LocalAlloc
|
|
;
|
|
;--------------------------------------------------------------------------;
|
|
|
|
szKernel: db "KERNEL",0
|
|
|
|
cProc LocalAlloc, <FAR, PUBLIC, PASCAL>
|
|
ParmW flags
|
|
ParmW bytes
|
|
cBegin
|
|
mov ax,word ptr [KernelLocalAlloc][0]
|
|
or ax,word ptr [KernelLocalAlloc][2]
|
|
jnz @f
|
|
|
|
lea ax,szKernel
|
|
cCall GetModuleHandle,<cs,ax>
|
|
cCall GetProcAddress,<ax, 0, 5>
|
|
|
|
mov word ptr [KernelLocalAlloc][0],ax
|
|
mov word ptr [KernelLocalAlloc][2],dx
|
|
|
|
@@: mov ax,word ptr [flatBase][0]
|
|
or ax,word ptr [flatBase][2]
|
|
pushf
|
|
jz @f
|
|
cCall FlatTerm
|
|
@@: cCall KernelLocalAlloc, <flags, bytes>
|
|
popf
|
|
jz @f
|
|
push ax
|
|
cCall FlatInit
|
|
pop ax
|
|
@@:
|
|
cEnd
|
|
|
|
;--------------------------------------------------------------------------;
|
|
;
|
|
; MapFlat - convert a 16:16 pointer into a 0:32 pointer
|
|
;
|
|
; note this function assumes the memory will *not* move
|
|
; while being accessed. If this is not true call GlobalFix
|
|
; on the memory
|
|
;
|
|
; INPUT:
|
|
; ptr16 16:16 pointer to map flat.
|
|
;
|
|
; OUTPUT:
|
|
; dx:ax flat pointer
|
|
;
|
|
;--------------------------------------------------------------------------;
|
|
assumes ds,Data
|
|
assumes es,nothing
|
|
|
|
cProc MapFlat, <NEAR>
|
|
ParmD ptr16
|
|
cBegin
|
|
mov ds,[flatSel]
|
|
|
|
push word ptr ptr16[2]
|
|
cCall GetSelectorBase
|
|
|
|
add ax,word ptr ptr16[0]
|
|
adc dx,0
|
|
|
|
sub ax,word ptr flatBase[0]
|
|
sbb dx,word ptr flatBase[2]
|
|
cEnd
|
|
|
|
sEnd
|
|
|
|
end
|