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Assembly Source File | 1995-11-01 | 20.1 KB | 465 lines

;============================================================================= ; AllKeys- Returns popup stolen key combinations back to the applications. ; Load "ALLKEYS" before and after your pop-ups. ; Then press Ctrl-Alt-Z to toggle ALLKEYS on/off. ; "beep..BEEP" signals all keys on. "BEEP..beep" signals all keys off. ;============================================================================= CSEG SEGMENT PARA PUBLIC 'CODE' ASSUME CS:CSEG, DS:CSEG, ES:CSEG, SS:CSEG ORG 100H FIRST: JMP INIT COPYRIGHT DB "ALLKEYS 1.0 (c) 1988 Ziff Communications Co.",13,10 DB "PC Magazine ",254," Robert L. Morton",13,10 DB "Low copy installed",13,10,"$" MESG1 DB "ALLKEYS high copy installed",13,10 DB "Ctrl-Alt-Z to toggle tsr's on/off",13,10,"$" MESG2 DB "ALLKEYS already installed high and low",13,10,"$" MESG3 DB "Vectors could not be restored - ALLKEYS disabled",13,10,"$" MESG4 DB "ALLKEYS not loaded yet",13,10,"$" MESG5 DB "ALLKEYS un-installed",13,10,"$" ORIG_INT9 DW 0,0 ;The original int 9 vector ORIG_INT16 DW 0,0 ;The original int 16h vector USED_INT9 DW 0,0 ;The used int 9 vector USED_INT16 DW 0,0 ;The used int 16h vector HOTKEY DB 44 ;Our HOT key: "Z" SHIFT_MASK DB 0CH ;Our shift mask: "Ctrl-Alt" ALLKEYS DB 0 ;Allkeys on/off status flag. DISABLE DB 0 ;If set to 1, Allkeys will not respond ; to Ctrl-Alt-Z combination and all ; keystrokes will be processed normally. TONE_LOW DW 500 ;Low boundary "beep" TONE_HIGH DW 1500 ;High boundary "BEEP" TONE_STEP DW 500 ;Step between tones TONE_LENGTH DW 50 ;Length of each tone ;----------------------------------------------------------------------------- ; New interrupt 9 handling routine. ;----------------------------------------------------------------------------- NEW_INT9 PROC NEAR ASSUME CS:CSEG, DS:NOTHING, ES:NOTHING, SS:NOTHING STI ;Enable interrupts PUSH AX ;Save AX CMP CS:DISABLE,0 ;Are we disabled? JNE KB1 ;Jump out if so. IN AL,60H ;Get key just pressed CMP AL,CS:HOTKEY ;Was it our HOT key? JNE KB2 ;If not, jump KB2 MOV AH,2 ;Get shift status. INT 16H AND AL,0FH ;Mask out shift keys CMP AL,CS:SHIFT_MASK ;Was it our shift mask? JNE KB2 ;If not, jump KB2 CALL KB_RESET ;Reset keyboard XOR CS:ALLKEYS,0FFH ;Toggle request flag CALL BEEP_STATUS ;Beep Allkeys' status KB1: POP AX ;Restore AX JMP DWORD PTR CS:USED_INT9 ;Exit through popup chain KB2: CMP CS:ALLKEYS,0 ;Allkeys' request flag set? JE KB1 ;If not, jump KB1 POP AX ;Restore AX JMP DWORD PTR CS:ORIG_INT9 ;Skip popup chain and exit ; directly to original. NEW_INT9 ENDP ;----------------------------------------------------------------------------- ; New interrupt 16h handling routine. ;----------------------------------------------------------------------------- NEW_INT16 PROC NEAR ASSUME CS:CSEG, DS:NOTHING, ES:NOTHING, SS:NOTHING STI ;Enable interrupts CMP CS:DISABLE,0 ;Are we disabled? JNE INT16_OUT ;Jump out if so. CMP CS:ALLKEYS,0 ;Allkeys' request flag set? JE INT16_OUT ;No - Leave through used 16h JMP DWORD PTR CS:ORIG_INT16 ;Yes- Leave through original INT16_OUT: JMP DWORD PTR CS:USED_INT16 NEW_INT16 ENDP ;----------------------------------------------------------------------------- ; Routine to beep Allkeys' status through the speaker. ; If Allkeys is on, "beep..BEEP". If Allkeys is off, "BEEP..beep". ;----------------------------------------------------------------------------- BEEP_STATUS PROC NEAR ASSUME CS:CSEG, DS:NOTHING, ES:NOTHING, SS:NOTHING PUSH CX ;Save needed registers PUSH DS PUSH CS ;Point DS to our data POP DS ASSUME DS:CSEG CMP ALLKEYS,0 ;Allkeys off? JE BS2 ;If so, jump BS2 ;Allkeys on - Ascend from a LOW tone to a HIGH tone. MOV CX,TONE_LOW ;Start at the bottom BS1: CALL SOUND ;Make the sound ADD CX,TONE_STEP ;Add the next step CMP CX,TONE_HIGH ;Are we over the top? JNA BS1 ;No - then keep on going JMP BS_OUT ;Yes- then jump out ;Allkeys off- Descend from a HIGH tone to a LOW tone. BS2: MOV CX,TONE_HIGH ;Start at the top BS3: CALL SOUND ;Make the sound SUB CX,TONE_STEP ;Subtract the next step CMP CX,TONE_LOW ;Are we below the bottom? JNB BS3 ;No, then keep on going BS_OUT: POP DS ;Restore used registers POP CX RET BEEP_STATUS ENDP ;----------------------------------------------------------------------------- ; Routine to produce a sound through the speaker. ; CX contains the frequency. Variable TONE_LENGTH contains the length. ;----------------------------------------------------------------------------- SOUND PROC NEAR ASSUME CS:CSEG, DS:CSEG, ES:NOTHING, SS:NOTHING PUSH AX ;Save needed registers PUSH CX PUSH DX ;Convert the frequency. MOV DX,12h ;Upper part MOV AX,34DEh ;Lower part DIV CX ;Divide by frequency MOV CX,AX ;to get quotient. ;Set the tone. MOV AL,CL ;Send low byte OUT 42h,AL ;out to the timer. MOV AL,CH ;Send high byte OUT 42h,AL ;out to the timer. ;Turn the tone on. IN AL,61h ;Get contents of system port B OR AL,3 ;Turn speaker and timer on OUT 61h,AL ;Send out new values to port B ;Delay MOV CX,TONE_LENGTH ;Put delay count in CX CALL DELAY ;Delay ;Turn the tone off. IN AL,61h ;Get port B again AND AL,0FCh ;Turn off timer and speaker OUT 61h,AL POP DX ;Restore used registers POP CX POP AX RET SOUND ENDP ;----------------------------------------------------------------------------- ; Routine to delay. CX contains the factor. ;----------------------------------------------------------------------------- DELAY PROC NEAR PUSH CX ;Save outside CX MOV CX,0FFH ;Move timing constant in CX DELAY1: LOOP DELAY1 ;Loop for inside POP CX ;Restore outside CX LOOP DELAY ;Loop for outside RET DELAY ENDP ;----------------------------------------------------------------------------- ; Routine to reset keyboard and 8259 interrupt controller. ;----------------------------------------------------------------------------- KB_RESET PROC NEAR IN AL,61H ;Get control port value MOV AH,AL ;Save in AH OR AL,80H ;Set bit 7 OUT 61H,AL ;Output reset value MOV AL,AH ;Send original value... JMP SHORT $+2 ;Take your time OUT 61H,AL ;...to enable keyboard CLI ;No interrupts now MOV AL,20H ;Send end of interrupt OUT 20H,AL ;value to 8259. STI ;Re-enable interrupts RET KB_RESET ENDP ;----------------------------------------------------------------------------- ; Initialization for Allkeys.... ;----------------------------------------------------------------------------- INIT PROC NEAR ASSUME CS:CSEG, DS:CSEG, ES:CSEG, SS:CSEG ;Check if the "/U" parameter was entered on the command line. MOV SI,80h ;Point to parm line CMP BYTE PTR [SI],0 ;Any chars entered? JNE INIT1 ;Yes-jump init1 JMP INIT8 ;No -jump init8 INIT1: MOV CL,[SI] ;Put parm length in CL XOR CH,CH ;Make 16 bit INC SI ;Point to next byte CLD ;Forward INIT2: LODSB ;Load a byte into AL CMP AL,"/" ;Is it our switch? JE INIT3 ;Jump if so LOOP INIT2 ;Keep on looking JMP INIT8 ;No switch found. Jump init8. INIT3: AND BYTE PTR [SI],0DFh ;Change char to uppercase CMP BYTE PTR [SI],"U" ;Is it a "U"? JE INIT4 ;Yes-jump init4 JMP INIT8 ;No -jump init8 ;"/U" parameter found. Make sure we're loaded. INIT4: CALL SEC_COPY ;Check for a second copy. JC INIT5 ;Jump if found. MOV DX,OFFSET MESG4 ;Print error message ERR_EXIT: MOV AH,9 INT 21H MOV AX,4C01h ;Terminate with errorlevel 1 INT 21H ;Modify resident copy to avoid future searches. INIT5: ASSUME DS:CSEG, ES:NOTHING PUSH ES ;Point DS at the resident POP DS ; copy of Allkeys. XOR AX,AX ;Point ES at the int vector MOV ES,AX ; table at bottom of memory. MOV WORD PTR [FIRST],0FFh ;This instruction modifies it ;Check if int 9 and 16h vectors point to the resident copy. MOV AX,DS ;Put seg of orig copy in AX CMP AX,ES:[ 9*4+2] ;Compare it to int 9 seg JNE INIT6 ;Jump if different CMP AX,ES:[16h*4+2] ;Compare it to int 16h seg JNE INIT6 ;Jump if different ;Int 9 and 16h vectors point to resident copy. ;Restore int 9 and 16h vectors and release resident copy from memory. ;Then terminate. ASSUME DS:NOTHING, ES:CSEG PUSH DS ;Point ES at the resident POP ES ; copy of Allkeys. MOV AX,2509H ;Restore interrupt 9 MOV DX,ES:[USED_INT9 ] MOV DS,ES:[USED_INT9+2] INT 21H MOV AX,2516H ;Restore interrupt 16h MOV DX,ES:[USED_INT16 ] MOV DS,ES:[USED_INT16+2] INT 21H MOV AH,49H ;Have DOS release it from INT 21H ; memory. ASSUME DS:CSEG, ES:CSEG PUSH CS ;Point DS back at our data POP DS MOV DX,OFFSET MESG5 ;Display status message. OK_EXIT: MOV AH,9 INT 21H MOV AX,4C00h ;Terminate with no errorlevel INT 21H ;Int 9 and 16h vectors do not point to resident copy. ;Check if resident copy was only installed LOW. INIT6: CMP USED_INT9,0 ;Only installed LOW? JNE INIT7 ;Jump if not ;Allkeys only installed LOW. ;Just simply release it from memory and terminate. ASSUME DS:CSEG, ES:CSEG PUSH DS ;Point ES at the resident POP ES ; copy of Allkeys. PUSH CS ;Point DS back to our data. POP DS MOV AH,49H ;Have DOS release it from INT 21H ; memory. MOV DX,OFFSET MESG5 ;Display OK message JMP OK_EXIT ; and terminate. ;Allkeys installed HIGH and LOW. ;Set DISABLE flag to disable Allkeys. Then terminate. INIT7: MOV DISABLE,1 ;Disable Allkeys MOV DX,OFFSET MESG3 ;Print error message JMP ERR_EXIT ; and terminate. ;"/U" parameter wasn't entered. Check to see if Allkeys already loaded. INIT8: ASSUME DS:CSEG, ES:CSEG CALL SEC_COPY ;Check for a second copy JC INIT9 ;Jump if found ;Second copy not found. ;Release the environment to conserve memory. ;Save the current interrupts 9 and 16h. Then TSR. ASSUME DS:CSEG, ES:NOTHING MOV AX,WORD PTR DS:[2CH] ;Release the environment. MOV ES,AX MOV AH,49H INT 21H MOV AX,3509H ;Get interrupt 9 INT 21H MOV [ORIG_INT9 ],BX ;Save the offset MOV [ORIG_INT9+2],ES ;Save the segment MOV AX,3516H ;Get interrupt 16h INT 21H MOV [ORIG_INT16 ],BX ;Save the offset MOV [ORIG_INT16+2],ES ;Save the segment MOV DX,OFFSET COPYRIGHT ;Display copyright MOV AH,9 INT 21H MOV AX,3100h ;Terminate and leave all MOV DX,(OFFSET INIT - OFFSET CSEG + 15) SHR 4 INT 21H ; code but the init portion ; resident in memory. (TSR) ;Second copy was found. ;Make sure Allkeys not already installed high and low. INIT9: ASSUME DS:CSEG, ES:CSEG PUSH ES ;Point DS at the original POP DS ; copy of Allkeys. CMP USED_INT9,0 ;Already installed high & low? JE INIT10 ;Jump if not. MOV DX,OFFSET MESG2 ;Display error message JMP ERR_EXIT ; and terminate. ;Obtain and save the used interrupts 9 and 16h to the original copy. INIT10: ASSUME DS:CSEG, ES:NOTHING MOV AX,3509H ;Get used interrupt 9 INT 21H MOV [USED_INT9 ],BX ;Save the offset MOV [USED_INT9+2],ES ;Save the segment MOV AX,3516H ;Get used interrupt 16h INT 21H MOV [USED_INT16 ],BX ;Save the offset MOV [USED_INT16+2],ES ;Save the segment ;Activate Allkeys by pointing interrupt vectors 9 and 16h ;to the resident copy's new interrupt 9 and 16h handlers. MOV AX,2509H ;Set interrupt 9 MOV DX,OFFSET NEW_INT9 INT 21H MOV AX,2516H ;Set interrupt 16h MOV DX,OFFSET NEW_INT16 INT 21H MOV DX,OFFSET MESG1 ;Display ready message JMP OK_EXIT ; and terminate. INIT ENDP ;----------------------------------------------------------------------------- ; Routine to search through memory for a previous loaded copy of Allkeys. ; If found, on return, CF will be set and ES will point to previous copy. ;----------------------------------------------------------------------------- SEC_COPY PROC NEAR ASSUME CS:CSEG, DS:CSEG, ES:NOTHING, SS:CSEG MOV WORD PTR [FIRST],0 ;Modify to avoid false alarm MOV BX,600h ;BX= start of our search MOV AX,CS ;AX= end of our search CLD ;Forward NEXT_PARA: INC BX ;Next paragraph CMP AX,BX ;If current paragraph... MOV ES,BX ;Set search segment JE END_SEARCH ;...stop MOV SI,OFFSET FIRST ;Compare FIRST label MOV DI,SI ;Offset is same MOV CX,16 ;Only FIRST 16 bytes REP CMPSB ;Compare DS:SI TO ES:DI OR CX,CX ;All matched? JNZ NEXT_PARA ;No, keep on looking. STC ;Found a copy in memory. RET ; Set CF and RETurn. END_SEARCH: CLC ;Didn't find a copy. RET ; Clear CF and RETurn. SEC_COPY ENDP CSEG ENDS END FIRST