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Assembly Source File | 1992-01-01 | 70KB | 1,473 lines

page 66,132 ;============================================================================= ; TEMPLATE - A template for a Terminate and stay resident program ; ; Written by Douglas Boling ; ; Revision History ; ; 1.0 Initial Release ; ;============================================================================= ;---------------------------------------------------------------------------- ; BIOS Data segment ;---------------------------------------------------------------------------- bios_data segment at 40h org 17h shift_state db ? ;State of keyboard shift keys org 4Eh video_buffoff dw ? ;Offset of video buffer org 63h video_ioregs dw ? ;I/O addr of video controller org 84h video_rows db ? ;Number of rows on the screen bios_data ends ;---------------------------------------------------------------------------- ; CODE segment ;---------------------------------------------------------------------------- code segment para public 'code' assume cs:code POPTIME EQU 18 ;Ticks allowed until popup RESSTACKSIZE EQU 512 ;Size of resident stack org 80h command_tail db ? org 100h begin: jmp initialize program db "Template 1.0 (c) 1992 Douglas Boling",13,10 db "Written by Douglas Boling$",26 ;----------------------------------------------------------------------------- ; Memory locations required for system overhead. ;----------------------------------------------------------------------------- hotshift db 0ah ;Shift combination for TSR ; <Alt> <Left shift> ; bit key ; 0 R Shift ; 1 L Shift ; 2 Ctrl ; 3 Alt dos_version dw 0 ;DOS version number mouse_flag db 0 ;Mouse driver present resident_sp dw 0 ;Resident stack pointer ems_flag db 0 ;Use expanded memory ems_segment dw 0 ;EMS page frame segment ems_version db 0 ;Version of EMS manager ems_handle dw 0 ;EMS handle used xms_flag db 0 ;Extended memory available xms_service dd -1 ;Entry pt for XMS manager xms_version db 0 ;Version of XMS manager indos_ptr dd -1 ;Pointer to INDOS flag criterr_ptr dd -1 ;Pointer to DOS crit err flag int08h dd -1 ;Int 2f vector (Timer) int09h dd -1 ;Int 09 vector (Keyboard HW) int10h dd -1 ;Int 10 vector (Video BIOS) int13h dd -1 ;Int 13 vector (Disk BIOS) int16h dd -1 ;Int 16 vector (BIOS Keyboard) int28h dd -1 ;Int 28 vector (DOS Idle) int2Fh dd -1 ;Int 2F vector (DOS Multiplex) int08_active db 0 ;Interrupt active flag int09_active db 0 ;Interrupt active flag int10_active db 0 ;Interrupt active flag int13_active db 0 ;Interrupt active flag int16_active db 0 ;Interrupt active flag int28_active db 0 ;Interrupt active flag int2F_active db 0 ;Interrupt active flag SWNotifyJT dw offset SWNInit ;Jump table used by switcher dw offset SWNQSuspend ; notification routine. dw offset SWNSuspend dw offset SWNActivate dw offset SWNActive dw offset SWNCSession dw offset SWNDSession dw offset SWNExit ;---------------------------------------------------------------------------- ;Switcher global data structures ;---------------------------------------------------------------------------- StartupInfo = $ sisVersion dw 3 ;Switcher structure ID sisNextDev dd 0 ;Ptr to prev startup structure sisVirtDevFile dd 0 ;Ptr to name of opt dev drvr sisReferenceData dd 0 ;Data for Win dev drivr sisInstData dd 0 ;Ptr to instance mem list InstItem1 dd 0 ;Ptr to instance data InstSize1 dw 0 ;Size of instance data InstItem2 dd 0 ;Ptr to instance stack InstSize2 dw 0 ;Size of instance stack dd 0 ;Ptr to next block = 0 to dw 0 ; terminate list ;============================================================================ ;Instance data ;============================================================================ TSRInstData = $ ;---------------------------------------------------------------------------- ;Switcher instance data structures ;---------------------------------------------------------------------------- SWService dd 0 ;Ptr to switcher service rtn CallbackInfo = $ scbiNext dd 0 ;Ptr to prev callback struc scbiEntryPoint dd 0 ;Ptr to local callback proc scbiReserved dd 0 ;Reserved scbiAPI dd 0 ;Ptr to info structures SwapInfo = $ dw 0 ;Zero swapinfo structure dw 0 ; since no API support dw 0 ; implimented by the TSR dw 0 dw 0 ;---------------------------------------------------------------------------- ;DOS State information ;---------------------------------------------------------------------------- saved_dta dd 0 ;saved pointer to curr DTA saved_psp dw 0 ;saved segment of curr PSP ss_register dw 0 ;SS register sp_register dw 0 ;SP register shift_save db 0 ;Keyboard shift lock state A20_state dw 0 ;Saved state of A20 line mem_alloc dw 0 ;DOS memory allocation strat linkflag db 0 ;DOS UMB link flag curr_disk db 0 ;Default disk at popup curr_dir db 64 dup (0) ;Default directory at popup errinfoarray: errAX dw 0 ;Saved extended error info errBX dw 0 errCX dw 0 errDX dw 0 errSI dw 0 errDI dw 0 errDS dw 0 errES dw 0 dw 3 dup (0) ;Reserved error table bytes vector1bh dd 0 ;int 1Bh vector (Break) vector23h dd 0 ;int 23h vector (Ctrl-C) vector24h dd 0 ;int 24h vector (Crit err) ;---------------------------------------------------------------------------- ;TSR State information ;---------------------------------------------------------------------------- popflag db 0 ;Request flag/timer main_active db 0 ;TSR active flag no_switch dw 0 ;Flag indicating switch OK ret_addr dw 0 ;Saved return addr for calls win_enhanced db 0 ;Enhanced mode windows flag TSRInstDataEnd = $ ;============================================================================ ; VIDEOINT processes BIOS video services interrupt (Int 10h) ;============================================================================ videoint proc far assume cs:code,ds:nothing,es:nothing inc cs:int10_active pushf call cs:[int10h] ;Call old int dec cs:int10_active iret ;Return videoint endp ;============================================================================= ; DISKINT receives control when an interrupt 13h is generated. ;============================================================================= diskint proc far assume cs:code,ds:nothing,es:nothing pushf ;save flags register inc cs:int13_active ;set disk access flag call cs:[int13h] pushf ;save flags again dec cs:int13_active ;reset disk access flag popf ;restore flags ret 2 ;exit with flags intact diskint endp ;============================================================================ ; BIOSKEYINT processes the BIOS keyboard services ;============================================================================ bioskeyint proc far assume cs:code,ds:nothing,es:nothing pushf ;save flags register inc cs:int16_active ;set keyboard active flag call cs:[int16h] pushf ;save flags again dec cs:int16_active ;reset keyborard avtive flag popf ;restore flags ret 2 ;exit with flags intact bioskeyint endp ;============================================================================ ; TIMERINT processes timer interrupt (Int 08h) ;============================================================================ timerint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int08h] ;Call old int 8 cmp cs:int08_active,0 ;See if we are in this jne timerint_exit ; routine already cmp cs:popflag,0 ;See if we need to try to jne timer_check ; pop up timerint_exit: iret ;Return timer_check: push ax inc cs:int08_active ;Set int active flag call check_system ;See if system OK to pop up or ax,ax jne timerint_dec call main ;Call the TSR mov cs:popflag,1 timerint_dec: dec cs:popflag dec cs:int08_active ;Clear int active flag pop ax jmp short timerint_exit timerint endp ;============================================================================ ; KEYINT processes keyboard interrupts (Int 09h) ;============================================================================ keyint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int09h] ;Call old int 9 push ax push ds mov ax,40h mov ds,ax ;Set ES to bios data segment assume ds:bios_data mov al,ds:[shift_state] and al,0fh ;Mask lock bits cmp al,cs:[hotshift] pop ds pop ax je keyint_hotkey keyint_exit: iret ;Return keyint_hotkey: mov cs:popflag,POPTIME ;Set timer to pop up jmp short keyint_exit keyint endp ;============================================================================ ; IDLEINT processes DOS Idle interrupt (Int 28h) ;============================================================================ idleint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int28h] ;Call old int cmp cs:int28_active,0 ;See if we are in this jne idleint_exit ; routine already cmp cs:popflag,0 ;See if we need to try to jne idle_check ; pop up idleint_exit: iret ;Return idle_check: push ax inc cs:int28_active ;Set int active flag call check_system ;See if OK to pop up. Ignore or al,al ; INDOS since in idle. jne idleint_exit1 mov cs:popflag,0 ;Clear popup flag call main ;Call the TSR idleint_exit1: dec cs:int28_active ;Clear int active flag pop ax jmp short idleint_exit idleint endp ;============================================================================ ; MUXINT processes the DOS Multiplex interrupt ;============================================================================ muxint proc far assume cs:code,ds:nothing,es:nothing cmp ax,1605h ;See if Windows start je init_win cmp ax,4b05h ;See if switcher get instance je init_instance ; data. cmp ax,4b01h ;See if switcher build chain je chain_init muxint_jmp: jmp cs:[int2fh] ;Call old int close_win: test dx,01h ;See if enhanced mode Windows jne muxint_jmp dec cs:win_enhanced ;Clear enhanced mode flag jmp short muxint_jmp init_win: test dx,01h ;See if enhanced mode Windows jne init_instance inc cs:win_enhanced init_instance: pushf call cs:[int2fh] ;Call old int mov word ptr cs:[sisNextDev],bx mov word ptr cs:[sisNextDev+2],es push cs ;ES:BX point to switcher struc pop es mov bx,offset StartupInfo jmp short muxint_exit chain_init: pushf call cs:[int2fh] ;Call old int mov word ptr cs:[scbiNext],bx mov word ptr cs:[scbiNext+2],es push cs ;ES:BX point to switcher struc pop es mov bx,offset CallbackInfo muxint_exit: iret muxint endp ;--------------------------------------------------------------------------- ; Check System Determines if the system is in a state compatible with TSRs ; Exit: CF - Clear if OK to pop up ;--------------------------------------------------------------------------- check_system proc near assume cs:code,ds:nothing,es:nothing push bx push ds xor ax,ax or al,cs:int10_active ;Check BIOS video int or al,cs:int13_active ;Check BIOS disk int or al,cs:int16_active ;Check BIOS keyboard int lds bx,cs:criterr_ptr ;Check DOS critical error or al,byte ptr ds:[bx] ; flag lds bx,cs:indos_ptr ;Check INDOS flag mov ah,byte ptr ds:[bx] check_sys_exit: pop ds pop bx ret check_system endp ;============================================================================= ; CRITICALERR receives control when an interrupt 24h is generated. ;============================================================================= criticalerr proc far assume cs:code,ds:nothing,es:nothing xor al,al ;Default to ignore cmp cs:dos_version,30ah ;See if before DOS 3.1 jl critical1 add al,3 critical1: iret criticalerr endp ;============================================================================= ; MAIN ;============================================================================= main proc near assume cs:code,ds:nothing,es:nothing cli inc cs:no_switch ;Don't allow switch inc cs:[main_active] ;set program status flag mov cs:ss_register,ss ;save SS and SP registers mov cs:sp_register,sp mov ax,cs ;switch to internal stack mov bx,resident_sp mov ss,ax mov sp,bx dec cs:no_switch sti ;enable interrupts call save_regs ;save all registers assume ds:code,es:nothing ;----------------------------------------------------------------------------- ;Point the interrupt 1Bh, 23h, and 24h vectors to internal handlers. ;----------------------------------------------------------------------------- mov ax,351bh ;get and save 1Bh vector int 21h mov word ptr vector1bh,bx mov word ptr vector1bh[2],es mov ax,251bh ;point interrupt to IRET mov dx,offset idleint_exit int 21h mov ax,3523h ;get and save 23h vector int 21h mov word ptr vector23h,bx mov word ptr vector23h[2],es mov ax,2523h ;Set to IRET mov dx,offset idleint_exit int 21h mov ax,3524h ;get and save 24h vector int 21h mov word ptr vector24h,bx mov word ptr vector24h[2],es mov ax,2524h ;point interrupt to internal mov dx,offset criticalerr ; critical error handler int 21h ;----------------------------------------------------------------------------- ;Save and switch to internal PSP ;----------------------------------------------------------------------------- mov ah,51h ;Get current PSP call dospspcall ;Beware DOS 2.0 - 3.0 mov saved_psp,bx ;save it push cs pop bx mov ah,50h ;Set internal PSP call dospspcall ;----------------------------------------------------------------------------- ;Save and switch to internal DTA ;----------------------------------------------------------------------------- mov ah,2fh int 21h ;Get current DTA mov word ptr saved_dta,bx ;save it mov word ptr saved_dta[2],es mov dx,offset command_tail ;use PSP for DTA mov ah,1ah ;Set DTA int 21h ;----------------------------------------------------------------------------- ;If DOS 3.x, save extended error information. ;----------------------------------------------------------------------------- cmp word ptr dos_version,030ah jb skip_err_save push ds ;save DS xor ax,ax ;Clear regs mov bx,ax mov cx,ax mov dx,ax mov di,ax mov si,ax mov ah,59h ;Extended error info int 21h ;Call DOS mov cs:[errDS],ds ;save returned DS pop ds ;Restore DS push bx mov bx,offset errinfoarray ;Save data in registers mov [bx],ax ; in this specific order. pop [bx+2] mov [bx+4],cx mov [bx+6],dx mov [bx+8],si mov [bx+10],di mov [bx+14],es skip_err_save: ;----------------------------------------------------------------------------- ;If using EMS memory, save EMS mapping context and map our page. ;----------------------------------------------------------------------------- cmp ems_flag,0 je skip_ems_save mov ah,47h ;Save mapping context mov dx,ems_handle int 67h or ah,ah jne clean_up xor ax,ax mov bx,ax call map_emsmem ;Map page jne clean_up skip_ems_save: ;----------------------------------------------------------------------------- ;Save default directory and drive ;----------------------------------------------------------------------------- mov ah,19h ;Get current disk int 21h mov curr_disk,al mov ah,47h ;Get current directory xor dl,dl mov si,offset curr_dir int 21h ;----------------------------------------------------------------------------- ;Save state of A20 line. ;----------------------------------------------------------------------------- cmp xms_flag,0 je skip_xms_save mov ah,7 ;Get state of A20 line call [xms_service] mov A20_state,ax skip_xms_save: ;----------------------------------------------------------------------------- ;Save UMB link and mem allocaton state. If DOS 5, link UMBs ;----------------------------------------------------------------------------- mov ax,5800h ;Get DOS mem alloc strategy int 21h mov mem_alloc,ax cmp dos_version,500h ;If DOS 5, save UMB link jb skip_umblink ; state. Then link UMBs mov ax,5802h int 21h mov linkflag,al ;Save UMB link state mov ax,5803h mov bx,1 ;Link UMBs int 21h skip_umblink: ;----------------------------------------------------------------------------- ;Save Mouse state ;----------------------------------------------------------------------------- cmp mouse_flag,0 je skip_mouse_save mov ax,17h mov dx,offset ResCodeEnd ;Save mouse state push cs pop es int 33h skip_mouse_save: ;----------------------------------------------------------------------------- ;Save Keyboard shift state ;----------------------------------------------------------------------------- mov ah,2 ;Get keyboard shift state int 16h mov shift_save,al ;============================================================================= ;Do work here ;============================================================================= mov ax,0e07h ;Beep the speaker int 10h work_1: mov ah,01 ;See if key available int 16h jne work_2 call TSR_idle ;Indicate TSR idle jmp short work_1 work_2: xor ah,ah int 16h cmp al,27 ;See if <Esc> key jne work_1 ;No, continue to wait mov ax,0e07h ;Beep the speaker again int 10h ;----------------------------------------------------------------------------- ;Clean up DOS for return to forground task. ;----------------------------------------------------------------------------- clean_up: push cs pop ds assume ds:code,es:nothing ;----------------------------------------------------------------------------- ;Restore Keyboard shift state ;----------------------------------------------------------------------------- mov ax,bios_data ;Point ES to BIOS data seg mov es,ax assume es:bios_data mov al,shift_save and al,0f0h ;Look only at lock bits mov es:[shift_state],al push cs pop es assume es:code ;----------------------------------------------------------------------------- ;Restore Mouse state ;----------------------------------------------------------------------------- cmp mouse_flag,0 je skip_mouse_restore mov ax,17h mov dx,offset ResCodeEnd ;Restore mouse state int 33h skip_mouse_restore: ;----------------------------------------------------------------------------- ;Restore UMB link state, link and allocation strat ;----------------------------------------------------------------------------- mov ax,5801h ;Set DOS mem alloc strategy mov bx,mem_alloc int 21h cmp dos_version,500h ;If DOS 5, restore UMB link jb skip_umblink_restore ; state. mov ax,5803h ;Set UMB link state xor bh,bh mov bl,linkflag int 21h skip_umblink_restore: ;----------------------------------------------------------------------------- ;Restore A20 line ;----------------------------------------------------------------------------- cmp xms_flag,0 je skip_xms_restore mov ah,5 ;Assume local disable A20 cmp A20_state,0 je xms_restore_1 inc ah ;Change to local enable A20 xms_restore_1: call [xms_service] ;Restore A20 line state mov A20_state,ax skip_xms_restore: ;----------------------------------------------------------------------------- ;If using EMS memory, restore EMS mapping context. ;----------------------------------------------------------------------------- cmp ems_flag,0 je ems_restore_skip mov ah,48h ;Restore mapping context mov dx,ems_handle int 67h ems_restore_skip: ;----------------------------------------------------------------------------- ;Restore default directory and drive ;----------------------------------------------------------------------------- mov ah,0eh ;Set default disk mov dl,curr_disk int 21h mov ah,3bh ;Set current directory mov dx,offset curr_dir int 21h ;----------------------------------------------------------------------------- ;Restore extended error info. ;----------------------------------------------------------------------------- cmp word ptr dos_version,30ah ;DOS 3.1 and up jb skip_err_restore mov ax,5d0ah ;Restore ext error info mov dx,offset errinfoarray ;point to Saved info int 21h skip_err_restore: ;----------------------------------------------------------------------------- ;Restore PSP and DTA ;----------------------------------------------------------------------------- mov bx,saved_psp ;Get old PSP mov ah,50h ;Restore PSP call dospspcall push ds lds dx,[saved_dta] mov ah,1ah ;Restore DTA int 21h ;----------------------------------------------------------------------------- ;Reset the displaced interrupt 1Bh, 23h, and 24h vectors. ;----------------------------------------------------------------------------- mov ax,2524h ;reset int 24h vector lds dx,cs:[vector24h] int 21h mov ax,2523h ;reset int 24h vector lds dx,cs:[vector23h] int 21h mov ax,251bh ;reset int 1Bh vector lds dx,cs:[vector1bh] int 21h pop ds ;----------------------------------------------------------------------------- ;Restore register values, switch back to original stack, and return to caller. ;----------------------------------------------------------------------------- main_exit: call restore_regs ;Restore registers assume ds:nothing cli ;make sure interrupts are off inc cs:no_switch ;Don't allow task switch mov ss,cs:ss_register ;switch to original stack mov sp,cs:sp_register dec cs:[main_active] ;clear program status flag dec cs:no_switch ;Allow task switch sti ;interrupts on ret ;Return to interrupt routine main endp ;----------------------------------------------------------------------------- ; DOSPSPCALL modifies critical error flag on PSP calls to DOS is using 2.x ;----------------------------------------------------------------------------- dospspcall proc near assume cs:code cmp cs:[dos_version],30Ah ;See if DOS < 3.1 jae dospspcall_ok ;no, just call DOS push ds push di lds di,cs:criterr_ptr ;retrieve crit err flag adr inc byte ptr [di] ;Set DOS in crit error state pop di pop ds int 21h ;Call DOS push ds push di lds di,cs:criterr_ptr ;retrieve crit err flag adr dec byte ptr [di] ;Set DOS in crit error state pop di pop ds ret dospspcall_ok: int 21h ;Call DOS ret dospspcall endp ;----------------------------------------------------------------------------- ; STOP SWITCH Signals the task switcher (if active) to not switch this ; session. ;----------------------------------------------------------------------------- stop_switch proc near assume cs:code inc cs:no_switch ;Set no switch flag for TS cmp win_enhanced,0 jne stop_switch_1 stop_switch_exit: ret stop_switch_1: mov ax,1681h ;Win begin critical section int 2fh jmp short stop_switch_exit stop_switch endp ;----------------------------------------------------------------------------- ; GO SWITCH Signals the task switcher (if active) it is OK to switch this ; session. ;----------------------------------------------------------------------------- go_switch proc near assume cs:code dec cs:no_switch ;Clear switch flag for TS cmp win_enhanced,0 jne go_switch_1 go_switch_exit: ret go_switch_1: mov ax,1682h ;Win end critical section int 2fh jmp short go_switch_exit go_switch endp ;----------------------------------------------------------------------------- ; TSR IDLE Signals the system that the TSR is idle. ;----------------------------------------------------------------------------- TSR_idle proc near assume cs:code int 28h ;Old DOS Idle cmp dos_version,300h ;No Multiplex interrupt for jb TSR_Idle_exit ; DOS 2.x mov ax,1680h ;Win-OS/2 release timeslice. int 2fh TSR_idle_exit: ret TSR_idle endp ;============================================================================ ; SWNOTIFY Routine to parse switcher notification messages ;============================================================================ SWNotify proc far assume cs:code,ds:nothing,es:nothing push si push ds push cs pop ds assume ds:code mov word ptr [SWService],di ;Save ptr to service rtn mov word ptr [SWService+2],es cmp ax,7 ja SWN1 ;If unknown type, skip mov si,ax shl si,1 call [SWNotifyJT+si] ;Call proper notification func mov ax,0 SWN1: pop ds pop si ret ;--------------------------------------------------------------------------- ; SWINIT - Switcher initialization notification ;--------------------------------------------------------------------------- SWNInit proc near assume cs:code,ds:code mov ax,0 ;Allow switcher init ret SWNInit endp ;--------------------------------------------------------------------------- ; SWQSUSPENDINIT - Switcher query suspend notification ;--------------------------------------------------------------------------- SWNQSuspend proc near assume cs:code,ds:code mov ax,no_switch ;Switch only if not in ret ; critical section SWNQSuspend endp ;--------------------------------------------------------------------------- ; SWSUSPEND - Switcher suspend notification ;--------------------------------------------------------------------------- SWNSuspend proc near assume cs:code,ds:code mov ax,no_switch ;Switch only if not in ret ; critical section SWNSuspend endp ;--------------------------------------------------------------------------- ; SWACTIVATE - Switcher going active notification ;--------------------------------------------------------------------------- SWNActivate proc near assume cs:code,ds:code mov ax,0 ;Allow session activate ret SWNActivate endp ;--------------------------------------------------------------------------- ; SWACTIVE - Switcher session active notification ;--------------------------------------------------------------------------- SWNActive proc near assume cs:code,ds:code mov ax,0 ;Allow session activate ret SWNActive endp ;--------------------------------------------------------------------------- ; SWCSESSION - Switcher create session notification ;--------------------------------------------------------------------------- SWNCSession proc near assume cs:code,ds:code mov ax,0 ;Allow session create ret SWNCSession endp ;--------------------------------------------------------------------------- ; SWDSESSION - Switcher destroy session notification ;--------------------------------------------------------------------------- SWNDSession proc near assume cs:code,ds:code mov ax,0 ;Allow session destroy ret SWNDSession endp ;--------------------------------------------------------------------------- ; SWEXIT - Switcher exit notification ;--------------------------------------------------------------------------- SWNExit proc near assume cs:code,ds:code mov ax,0 ;Allow switcher exit ret SWNExit endp SWNotify endp ;----------------------------------------------------------------------------- ; GETEMSMEM Allocates pages of memory from the Expanded memory manager ; Entry: BX - number of 16K pages to request ; Exit: DX - handle to pages ; ZF - Set if call successful ;----------------------------------------------------------------------------- get_emsmem proc near mov ah,43h ;Allocate EMS pages int 67h or ah,ah ret get_emsmem endp ;----------------------------------------------------------------------------- ; FREEEMSMEM Frees pages of memory from the Expanded memory manager ; Entry: DX - handle to memory pages to free ; Exit: ZF - Set if call successful ;----------------------------------------------------------------------------- free_emsmem proc near mov ah,45h ;Free EMS page int 67h or ah,ah ret free_emsmem endp ;----------------------------------------------------------------------------- ; MAPEMSMEM Maps a page of Expanded memory to the EMS page frame ; Entry: AL - Physical page in page frame ; BX - logical page to map ; DX - handle to memory pages ; Exit: ZF - Set if call successful ;----------------------------------------------------------------------------- map_emsmem proc near mov ah,44h ;Map EMS page int 67h or ah,ah ret map_emsmem endp ;----------------------------------------------------------------------------- ; SAVEREGS saves all the registers used in the interrupt routines and sets DS. ;----------------------------------------------------------------------------- save_regs proc near pop cs:[ret_addr] ;Get address to return to push ax ;save all registers push bx push cx push dx push bp push si push di push ds push es push cs ;Set DS = CS pop ds assume ds:code jmp word ptr [ret_addr] ;Return save_regs endp ;----------------------------------------------------------------------------- ;RESTOREREGS restores register values. ;----------------------------------------------------------------------------- restore_regs proc near pop ret_addr ;Save return address pop es ;restore registers pop ds assume ds:nothing pop di pop si pop bp pop dx pop cx pop bx pop ax jmp word ptr cs:[ret_addr] ;Return restore_regs endp ;============================================================================= ; End of resident code. Resident stack and mouse save area sits just ; above resident code ;============================================================================= ResCodeEnd = $ ;============================================================================= ; Non-Resident data ;============================================================================= errmsg1 db 13,10,"Usage: TEMPLATE [/U][/X][/E]$" errmsg2 db "Bad switch$" errmsg3 db "Expanded memory driver not found$" errmsg4 db "DOS 2.0 or greater required$" errmsg5 db "Not able to uninstall$" errmsg6 db "TEMPLATE not installed$" infomsg1 db "TEMPLATE installed$" infomsg2 db "TEMPLATE removed$" errmsg8 db "Program uninstalled$" errmsg9 db "Can't install$" installed_seg dw 0 ;Segment of installed code TSRResident db 0 ;TSR already installed flag def_disk db ? ;Default disk drive ems_header db "EMMXXXX0" ;EMS driver header mouse_savesize dw 0 ;Size of mouse save area cmd_switches db "eu" ;Letters of valid commands. cmd_switch_end = $ cmd_jmptbl dw offset remove ;Jump table to rouines that dw offset use_expanded ; impliment the cmd line args ;============================================================================= ; INITIALIZE ;============================================================================= initialize proc near assume cs:code, ds:code cld ;String operations UP mov dx,offset program ;Print copyright call message ;----------------------------------------------------------------------------- ;Get DOS version, Determine if TSR already installed. ;----------------------------------------------------------------------------- mov ah,30h ;Get DOS version int 21h xchg al,ah ;Put version in proper order mov dos_version,ax ;Save DOS version cmp ax,200h ;See if at least DOS ver 2 ja init_0 mov dx,offset errmsg4 jmp short error_exit init_0: call find_copy ;See if TSR already installed jc init_1 inc TSRResident ;Set already installed flag mov installed_seg,es ;save installed code segment init_1: push cs pop es ;----------------------------------------------------------------------------- ;Parse the command line for switches. ;----------------------------------------------------------------------------- mov di,offset command_tail ;Point SI to command line text xor cx,cx or cl,[di] ;Get length of command line. jz init_3 ;If 0, skip parse inc di init_2: mov al,"/" ;Put switch in AL repne scasb ;Scan for cmd line switches jne init_3 mov al,[di] or al,20h ;Make lower case push cx push di mov di,offset cmd_switches mov cx,offset cmd_switch_end - offset cmd_switches repne scasb mov bx,cx ;Copy index into list pop di pop cx mov dx,offset errmsg2 ;Command not found msg jne error_exit shl bx,1 ;Convert to word offset push cx push di call cs:[bx+cmd_jmptbl] ;Call command routine. pop di pop cx jc error_exit ;If error terminate parse. jcxz init_3 ;If at file end, exit parse. jmp short init_2 init_3: ;----------------------------------------------------------------------------- ;If not installed, install. ;----------------------------------------------------------------------------- cmp TSRResident,0 ;Is TSR installed? je install mov ax,4c00h ;No, terminate with RC = 0. int 21h ;============================================================================= ;Display error message and exit with Return Code = 1. ;============================================================================= error_exit: call message mov es,installed_seg ;point ES to installed code dec es:[main_active] ;enable background task. mov ax,4c01h ;Exit RC = 1 int 21h ;============================================================================= ;Install. Get address of INDOS and DOS Critical Error flags. ;============================================================================= install: mov ah,34h ;Get INDOS address from DOS int 21h mov word ptr [indos_ptr],bx mov word ptr [indos_ptr+2],es call find_cefptr ;Find critical error flag jnc ceffound mov dx,offset errmsg9 ;Critical error flag not found jmp short error_exit ceffound: mov word ptr criterr_ptr,bx ;store it mov word ptr criterr_ptr[2],es ;----------------------------------------------------------------------------- ;Initialize task switcher structures. See if task switcher active. ;----------------------------------------------------------------------------- cmp word ptr dos_version,300h ;DOS 3.0 and up jb nowin mov ax,offset TSRInstData ;Init instance memory struc mov word ptr [InstItem1],ax mov word ptr [InstItem1+2],cs mov ax,offset TSRInstDataEnd - offset TSRInstData mov [InstSize1],ax mov ax,offset ResCodeEnd ;Init instance stack struc mov word ptr [InstItem2],ax mov word ptr [InstItem2+2],cs mov ax,RESSTACKSIZE mov [InstSize2],ax mov ax,offset InstItem1 ;Init ptr to instance mov word ptr [sisInstData],ax ; memory structure. mov word ptr [sisInstData+2],cs mov ax,offset SWNotify ;Init ptr to mov word ptr [scbiEntryPoint],ax ; notification mov word ptr [scbiEntryPoint+2],cs ; routine. mov ax,4b02h ;See if switcher active int 2fh ;Use multiplex interrupt or ax,ax jne noswitcher mov word ptr [SWService],di ;Save ptr to service routine mov word ptr [SWService+2],es mov ax,4 ;Hook notification chain push cs ;ES:BX point to callback struc pop es mov di,offset CallbackInfo call SWService noswitcher: ;----------------------------------------------------------------------------- ;Check for Windows active ;----------------------------------------------------------------------------- mov ax,1600h ;See if Enhanced mode windows int 2fh or al,al je nowin inc win_enhanced ;Set enhanced mode flag nowin: ;----------------------------------------------------------------------------- ;Determine if extended memory manager active ;----------------------------------------------------------------------------- mov ax,4300h ;Look for HIMEM.SYS int 2fh or al,al jne noxms mov ax,4310h ;Get entry point for XMM int 2fh mov word ptr [xms_service],bx mov word ptr [xms_service+2],es push cs pop es inc xms_flag noxms: ;----------------------------------------------------------------------------- ;Set up EMS memory if necessary. ;----------------------------------------------------------------------------- cmp ems_flag,0 ;See if expanded memory je no_emsmem ; requested call check4ems ;See if EMS driver installed jnc install_1 mov dx,offset errmsg3 ;EMS driver error jmp error_exit install_1: mov ems_segment,bx ;Save seg of EMS page frame mov ems_version,dl ;Save EMS version mov bx,1 ;Allocate 1 page call get_emsmem mov ems_handle,dx ;Save EMS handle xor al,al ;Map to EMS page 0 xor bx,bx call map_emsmem no_emsmem: ;----------------------------------------------------------------------------- ;See if mouse driver loaded ;----------------------------------------------------------------------------- xor ax,ax int 33h or ax,ax je no_mouse inc mouse_flag ;Set mouse found flag, get mov ax,15h ; size of mouse driver save int 33h ; context area. mov mouse_savesize,bx no_mouse: ;----------------------------------------------------------------------------- ;Set interrupts used by TSR ;----------------------------------------------------------------------------- mov al,08h ;Get/set the timer interrupt mov dx,offset timerint mov di,offset int08h call set_interrupt mov al,09h ;Get/set the keyboard int mov dx,offset keyint mov di,offset int09h call set_interrupt mov al,10h ;Get/set the video interrupt mov dx,offset videoint mov di,offset int10h call set_interrupt mov al,13h ;Get/set the disk interrupt mov dx,offset diskint mov di,offset int13h call set_interrupt mov al,16h ;Get/set the BIOS keyboard int mov dx,offset bioskeyint mov di,offset int16h call set_interrupt mov al,28h ;Get/set the DOS idle int mov dx,offset idleint mov di,offset int28h call set_interrupt cmp dos_version,300h ;DOS 3.0 and up jb skip_hook2f mov al,2fh ;Get/set the DOS multiplex int mov dx,offset muxint mov di,offset int2fh call set_interrupt skip_hook2f: ;----------------------------------------------------------------------------- ;Deallocate the program's environment block. ;----------------------------------------------------------------------------- mov ax,ds:[2ch] ;get environment segment mov es,ax mov ah,49h ;free it int 21h mov dx,offset infomsg1 ;Tell user that we are call message ; installed. mov ax,3100h ;terminate with ERRORLEVEL = 0 mov dx,offset ResCodeEnd-offset code + RESSTACKSIZE add dx,mouse_savesize mov resident_sp,dx add dx,15 mov cl,4 shr dx,cl int 21h initialize endp ;----------------------------------------------------------------------------- ; USE EXPANDED Sets a flag to use expanded memory ;----------------------------------------------------------------------------- use_expanded proc near mov ems_flag,1 ret use_expanded endp ;----------------------------------------------------------------------------- ; REMOVE deallocates the memory block addressed by ES and restores the ; interrupt vectors displaced on installation. ; Exit: CF clear - program uninstalled ; CF set - can't uninstall ;----------------------------------------------------------------------------- remove proc near assume cs:code,ds:code cmp TSRResident,0 ;See if TSR installed jne remove_1 mov dx,offset errmsg6 jmp remove_error1 remove_1: mov es,installed_seg mov ax,5 ;Unhook notification chain mov di,offset CallbackInfo cmp word ptr es:[SWService+2],0 je remove_2 call es:[SWService] remove_2: mov al,8 ;check interrupt 8 vector call checkvector jne jmp_remove_error mov al,9 ;check interrupt 9 vector call checkvector jne jmp_remove_error mov al,10h ;check interrupt 10 vector call checkvector jne jmp_remove_error mov al,13h ;check interrupt 13h vector call checkvector jne jmp_remove_error mov al,16h ;check interrupt 16 vector call checkvector jne jmp_remove_error mov al,28h ;check interrupt 28h vector call checkvector je remove_3 jmp_remove_error: jmp remove_error remove_3: cmp dos_version,300h ;DOS 3.0 and up jb skip_check2f mov al,2Fh ;check interrupt 2Fh vector call checkvector jne remove_error skip_check2f: cmp ems_flag,0 ;If using Expanded memory je skip_remove_ems ; free it mov dx,ems_handle ;Free Expanded memory call free_emsmem jne remove_error skip_remove_ems: push ds ;save DS assume ds:nothing mov ax,2508h ;restore interrupt 8 vector lds dx,es:[int08h] int 21h mov ax,2509h ;restore interrupt 9 vector lds dx,es:[int09h] int 21h mov ax,2510h ;restore interrupt 10 vector lds dx,es:[int10h] int 21h mov ax,2513h ;restore interrupt 13h vector lds dx,es:[int13h] int 21h mov ax,2516h ;restore interrupt 16 vector lds dx,es:[int16h] int 21h mov ax,2528h ;restore interrupt 28h vector lds dx,es:[int28h] int 21h cmp cs:dos_version,300h ;DOS 3.0 and up jb skip_restore2f mov ax,252Fh ;restore interrupt 2Fh vector lds dx,es:[int2Fh] int 21h skip_restore2f: pop ds ;Restore DS assume ds:code not word ptr es:[begin] ;Destroy fingerprint mov ah,49h ;Free memory given to int 21h ; original program block jc remove_error ;branch on error mov dx,offset infomsg2 ;Indicate program removed call message clc ;clear CF for exit remove_exit: ret ;exit with CF intact remove_error: mov dx,offset errmsg5 remove_error1: stc jmp remove_exit ;Error during remove remove endp ;----------------------------------------------------------------------------- ; CHECKVECTOR is called by REMOVE to compare the segment pointed to by an ; interrupt vector against a segment value supplied by the caller. ; Entry: AL - interrupt number ; Exit: ZF clear - segments do not match ; ZF set - segments match ;----------------------------------------------------------------------------- checkvector proc near push es mov cx,es mov ah,35h ;get vector int 21h mov ax,es ;transfer segment to AX cmp ax,cx ;compare pop es ret checkvector endp ;----------------------------------------------------------------------------- ; SETINTERRUPT Get and sets an interrupt ; Entry: AL - Interrupt number ; DX - Pointer to new interrupt routine ; DI - Pointer to storage location for old interrupt vector ;----------------------------------------------------------------------------- assume cs:code,ds:code,es:nothing set_interrupt proc near push es push ax mov ah,35h ;DOS get interrupt int 21h pop ax mov word ptr [di],bx ;Save old vector mov word ptr [di+2],es mov ah,25h ;DOS set interrupt int 21h pop es ret set_interrupt endp ;----------------------------------------------------------------------------- ; FINDCOPY Determines if the TSR is already resident ; Exit: CF - Clear if copy found ; ES - Segment of installed code (if CF = 0) ;----------------------------------------------------------------------------- find_copy proc near not word ptr [begin] ;initialize fingerprint mov bx,0a000h ;Start scan in UMBs mov ax,cs ;keep CS value in AX find_copy1: inc bx ;increment search segment value mov es,bx cmp ax,bx ;not installed if current je find_copy2 ; segment is looped back to mov si,offset begin ;search this segment for ASCII mov di,si ; fingerprint mov cx,16 repe cmpsb jne find_copy1 ;loop back if not found clc ;Set copy found flag find_copy_exit: ret find_copy2: stc jmp short find_copy_exit ret find_copy endp ;----------------------------------------------------------------------------- ; GETCEFPtr Returns a pointer to the DOS ErrorMode flag ; Exit: CF - Clear if ErrorMode Flag found ; ES:BX - Segment:offset of ErrorMode flag ; ; For versions of DOS before 3.1, search for following code in DOS seg ; ; 36: 80 3E ???? 00 cmp byte ptr ss:[ErrorMode],0 ; 75 ?? jne near label ; CD 28 int 28h ; ; For DOS 3.1 and later, ErrorMode sits before InDOS flag ; ;----------------------------------------------------------------------------- find_cefptr proc near mov ah,34h ;Get ptr to INDOS int 21h ;After DOS 3.1, the CEF is dec bx ; documented to be the byte cmp dos_version,30ah ; before the INDOS flag jnc find_cef_exit mov ax,3e80h ;CMP opcode mov cx,-1 ;Max segment size mov di,bx ;Start at INDOS address find_cef_1: repne scasb ;Scan for CMP jcxz find_cef_notfound ;Error if CMP not found cmp es:[di],ah ;Check other half of CMP opcode jne find_cef_1 cmp byte ptr es:[di+4],075h ;Check for JNE jne find_cef_1 cmp word ptr es:[di+6],028cdh ; Check for Int 28h call jne find_cef_1 ;Resume loop if not found find_cef_found: inc di mov bx,es:[di] ;Get offset of ErrorMode flag clc find_cef_exit: ret find_cef_notfound: stc jmp short find_cef_exit find_cefptr endp ;----------------------------------------------------------------------------- ; CHECK4EMS Determines if an Expanded memory driver is loaded. ; Exit: BX - Segment of EMS page frame if CF clear ; DL - EMS driver version number ; CF - Clear if EMS driver found ;----------------------------------------------------------------------------- check4ems proc near push es push di mov ax,3567h ;Get EMS vector int 21h mov di,0ah ;Using the segment from the mov si,offset ems_header ; 67h vector, look at offset mov cx,8 ; 0ah. Compare the next 8 cld ; bytes with the expected repe cmpsb ; EMS header. If they are pop di ; the same, EMS driver pop es ; found. je check4ems_found check4ems_error: stc ;Set not found flag jmp short check4ems_exit check4ems_found: mov ah,40h ;Check status int 67h or ah,ah jne check4ems_error mov ah,41h ;Get page frame segment int 67h or ah,ah jne check4ems_error mov ah,47h ;Get EMM version number int 67h or ah,ah jne check4ems_error mov dl,al ;Copy version number check4ems_exit: ret check4ems endp ;---------------------------------------------------------------------- ; MESSAGE Prints a message to screen ; Entry: DX - Offset of '$' terminated message ;---------------------------------------------------------------------- crlf$ db 13,10,"$" message proc near assume cs:code,ds:code mov ah,9 ;Print string int 21h mov dx,offset crlf$ ;Append carrage return mov ah,9 int 21h ret message endp EndOfCode = $ code ends end begin