| Line 478... |
Line 478... |
| 478 |
int 0x21 ; segment of the original PSP is in BX now
|
478 |
int 0x21 ; segment of the original PSP is in BX now
|
| 479 |
|
479 |
|
| 480 |
; set DS to the original PSP
|
480 |
; set DS to the original PSP
|
| 481 |
mov ds, bx
|
481 |
mov ds, bx
|
| 482 |
|
482 |
|
| 483 |
; load the pointer to the JFT, save it on stack, and set DS to the JFT seg
|
483 |
; load the pointer to the original JFT, set DS to the JFT seg and BX to offset
|
| 484 |
lds bx, [0x34] ; loads offset at [0x34] into BX and segment at [0x36] into DS
|
484 |
lds bx, [0x34] ; same as "mov bx, [0x34]" + "mov ds, [0x36]", but smaller
|
| - |
|
485 |
|
| - |
|
486 |
; save the original process stdin and stdout (at [BX]) on stack, as well as a
|
| - |
|
487 |
; dword pointer to the original JFT
|
| 485 |
; same as "mov bx, [0x34]" + "mov ds, [0x36]", but smaller
|
488 |
push word [bx] ; original stdin and stdout (from the JFT at DS:BX)
|
| 486 |
push ds
|
489 |
push ds
|
| 487 |
push bx
|
490 |
push bx
|
| 488 |
|
491 |
|
| 489 |
; save the original process stdin and stdout (at [BX]) on stack
|
- |
|
| 490 |
push word [bx] ; original stdin and stdout (from the JFT)
|
- |
|
| 491 |
|
- |
|
| 492 |
; overwrite the original process stdin and stdout with stderr, in case stdout
|
492 |
; overwrite the original process stdin and stdout with stderr, in case stdout
|
| 493 |
; or stdin was redirected.
|
493 |
; or stdin was redirected.
|
| 494 |
mov dl, [bx+2] ; the process stderr (3rd entry of the JFT in original PSP)
|
494 |
mov dl, [bx+2] ; the process stderr (3rd entry of the JFT in original PSP)
|
| 495 |
mov dh, dl ; dup DL so I can overwrite stdin and stdout with one write
|
495 |
mov dh, dl ; dup DL so I can overwrite stdin and stdout with one write
|
| 496 |
mov [bx], dx
|
496 |
mov [bx], dx
|
| Line 640... |
Line 640... |
| 640 |
jmp CRITERR_ASKCHOICE ; invalid answer -> ask again
|
640 |
jmp CRITERR_ASKCHOICE ; invalid answer -> ask again
|
| 641 |
|
641 |
|
| 642 |
QUIT_WITH_AL_SET:
|
642 |
QUIT_WITH_AL_SET:
|
| 643 |
|
643 |
|
| 644 |
; restore original stdin/stdout handlers in the original JFT
|
644 |
; restore original stdin/stdout handlers in the original JFT
|
| 645 |
pop dx ; original process' stdin and stdout handlers
|
645 |
pop bx ; original process' JFT offset
|
| 646 |
pop bx ; original process' JFT offset
|
646 |
pop ds ; original process' JFT segment
|
| 647 |
pop ds ; original process' JFT segment
|
647 |
pop word [bx] ; original process' stdin and stdout handlers
|
| 648 |
mov [bx], dx
|
- |
|
| 649 |
|
648 |
|
| 650 |
; restore registers to their original values and quit the handler (AL is
|
649 |
; restore registers to their original values and quit the handler (AL is
|
| 651 |
; already set to a proper action value and AH does not matter since it was
|
650 |
; already set to a proper action value and AH does not matter since it was
|
| 652 |
; changed by the kernel's int 24h calling routine anyway)
|
651 |
; changed by the kernel's int 24h calling routine anyway)
|
| 653 |
popf
|
652 |
popf
|