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Assembly Source File | 1994-03-08 | 34.7 KB | 924 lines

;--------------------------------------------------------------------------; ; Program: DAT .Asm ; ; Purpose: Displays current date and time. ; ; Notes: Compiles under TURBO Assembler, v3.0. Should work on any ; ; machine running MS-DOS, v2.xx or higher. ; ; Status: Released into the public domain. Enjoy! If you use it, ; ; let me know what you think. You don't have to send ; ; any money, just comments and suggestions. ; ; Updates: 06-Mar-90, v1.0, GAT ; ; - initial version. ; ; 13-Mar-90, v1.1, GAT ; ; - added n option to suppress final CR/LF sequence. ; ; 19-Mar-90, GAT ; ; - fixed up on-line help message. ; ; 22-Apr-90, v1.2, GAT ; ; - revised most procedures based on work with ASK. ; ; 05-May-90, GAT ; ; - fixed bug in handling of non-zero return codes. ; ; 12-Jun-90, GAT ; ; - fixed bug in conv_Int2Ascii wrt DI's final value. ; ; 08-Jul-90, GAT ; ; - added macros to push/pop registers. ; ; 28-Aug-90, v1.3a, GAT ; ; - put equates and macros in separate files. ; ; - put common routines in libs. ; ; - added equates for date/time separators. ; ; 12-Oct-91, v1.3b, GAT ; ; - revised include file names. ; ; - replaced references to Push_M and Pop_M macros with ; ; calls to push and pop. ; ; - removed local stack: it's not necessary. ; ; 03-Jul-93, v1.3c, GAT ; ; - compiled with TASM v3.0. ; ; - version number now comes from makefile. ; ; - specified ??date in lowercase. ; ;--------------------------------------------------------------------------; ;--------------------------------------------------------------------------; ; Author: George A. Theall ; ; SnailMail: TifaWARE ; ; 610 South 48th St ; ; Philadelphia, PA. 19143 ; ; U.S.A. ; ; E-Mail: george@tifaware.com ; ; theall@popmail.tju.edu ; ; theall@mcneil.sas.upenn.edu ; ; george.theall@satalink.com ; ;--------------------------------------------------------------------------; ;--------------------------------------------------------------------------; ; D I R E C T I V E S ; ;--------------------------------------------------------------------------; DOSSEG MODEL tiny IDEAL LOCALS JUMPS FALSE EQU 0 TRUE EQU NOT FALSE BELL EQU 7 BS EQU 8 TAB EQU 9 CR EQU 13 LF EQU 10 ESCAPE EQU 27 ; nb: ESC is a TASM keyword SPACE EQU ' ' KEY_F1 EQU 3bh KEY_F2 EQU 3ch KEY_F3 EQU 3dh KEY_F4 EQU 3eh KEY_F5 EQU 3fh KEY_F6 EQU 40h KEY_F7 EQU 41h KEY_F8 EQU 42h KEY_F9 EQU 43h KEY_F10 EQU 44h KEY_HOME EQU 47h KEY_UP EQU 48h KEY_PGUP EQU 49h KEY_LEFT EQU 4bh KEY_RIGHT EQU 4dh KEY_END EQU 4fh KEY_DOWN EQU 50h KEY_PGDN EQU 51h KEY_INS EQU 52h KEY_DEL EQU 53h KEY_C_F1 EQU 5eh KEY_C_F2 EQU 5fh KEY_C_F3 EQU 60h KEY_C_F4 EQU 61h KEY_C_F5 EQU 62h KEY_C_F6 EQU 63h KEY_C_F7 EQU 64h KEY_C_F8 EQU 65h KEY_C_F9 EQU 66h KEY_C_F10 EQU 67h KEY_C_LEFT EQU 73h KEY_C_RIGHT EQU 74h KEY_C_END EQU 75h KEY_C_PGDN EQU 76h KEY_C_HOME EQU 77h KEY_C_PGUP EQU 84h KEY_F11 EQU 85h KEY_F12 EQU 86h KEY_C_F11 EQU 89h KEY_C_F12 EQU 8ah @16BIT EQU (@Cpu AND 8) EQ 0 @32BIT EQU (@Cpu AND 8) NOWARN RES MACRO PUSHA ;; Pushs all registers IF @Cpu AND 2 ;; if for 80186 or better pusha ;; use regular opcode ELSE ;; else push ax cx dx bx sp bp si di ;; nb: order matters! ;; nb: SP is not original! ENDIF ENDM MACRO POPA ;; Pops all registers IF @Cpu AND 2 ;; if for 80186 or better popa ;; use regular opcode ELSE ;; else pop di si bp bx bx dx cx ax ;; nb: order matters! ;; nb: don't pop SP! ENDIF ENDM NOWARN RES MACRO ZERO RegList ;; Zeros registers IRP Reg, <RegList> xor Reg, Reg ENDM ENDM DOS EQU 21h ; main MSDOS interrupt STDIN EQU 0 ; standard input STDOUT EQU 1 ; standard output STDERR EQU 2 ; error output STDAUX EQU 3 ; COM port STDPRN EQU 4 ; printer TSRMAGIC EQU 424bh ; magic number STRUC ISR Entry DW 10EBh ; short jump ahead 16 bytes OldISR DD ? ; next ISR in chain Sig DW TSRMAGIC ; magic number EOIFlag DB ? ; 0 (80) if soft(hard)ware int Reset DW ? ; short jump to hardware reset Reserved DB 7 dup (0) ENDS STRUC ISRHOOK Vector DB ? ; vector hooked Entry DW ? ; offset of TSR entry point ENDS STRUC TSRSIG Company DB 8 dup (" ") ; blank-padded company name Product DB 8 dup (" ") ; blank-padded product name Desc DB 64 dup (0) ; ASCIIZ product description ENDS GLOBAL at : PROC GLOBAL errmsg : PROC GLOBAL ProgName : BYTE ; needed for errmsg() GLOBAL EOL : BYTE ; ditto GLOBAL fgetc : PROC GLOBAL fputc : PROC GLOBAL fputs : PROC GLOBAL getchar : PROC GLOBAL getdate : PROC GLOBAL getswtch : PROC GLOBAL gettime : PROC GLOBAL getvdos : PROC GLOBAL getvect : PROC GLOBAL isatty : PROC GLOBAL kbhit : PROC GLOBAL pause : PROC GLOBAL putchar : PROC GLOBAL setvect : PROC GLOBAL sleep : PROC GLOBAL find_NextISR : PROC GLOBAL find_PrevISR : PROC GLOBAL hook_ISR : PROC GLOBAL unhook_ISR : PROC GLOBAL free_Env : PROC GLOBAL fake_Env : PROC GLOBAL check_ifInstalled : PROC GLOBAL install_TSR : PROC GLOBAL remove_TSR : PROC GLOBAL atoi : PROC GLOBAL atou : PROC GLOBAL utoa : PROC EOS EQU 0 ; terminates strings GLOBAL isalpha : PROC GLOBAL isdigit : PROC GLOBAL islower : PROC GLOBAL isupper : PROC GLOBAL iswhite : PROC GLOBAL memcmp : PROC GLOBAL strchr : PROC GLOBAL strcmp : PROC GLOBAL strlen : PROC GLOBAL tolower : PROC GLOBAL toupper : PROC ERRH equ 1 ; errorlevel if help given DATE_SEP equ '/' ; date separator TIME_SEP equ ':' ; time separator ;--------------------------------------------------------------------------; ; C O D E S E G M E N T ; ;--------------------------------------------------------------------------; CODESEG ORG 80h ; commandline LABEL CmdLen BYTE db ? LABEL CmdLine BYTE db 127 dup (?) ORG 100h ; start of .COM file STARTUPCODE jmp main ; skip over data and stack ;--------------------------------------------------------------------------; ; D A T A ; ;--------------------------------------------------------------------------; LABEL ProgName BYTE db 'dat: ', EOS LABEL EOL BYTE db '.', CR, LF, EOS LABEL HelpMsg BYTE db CR, LF db 'TifaWARE DAT, v', VERS_STR, ', ', ??date db ' - displays the current date and time.', CR, LF db 'Usage: dat [-options] [msg]', CR, LF, LF db 'Options:', CR, LF db ' -d = display date', CR, LF db ' -n = suppress final newline sequence', CR, LF db ' -t = display time', CR, LF db ' -? = display this help message', CR, LF, LF db 'msg is an optional message to display before ' db 'the date or time.', CR, LF, EOS LABEL Err1Msg BYTE db 'illegal option -- ' LABEL OptCh BYTE db ? db EOS LABEL TwoDigits BYTE ; space for two digits db 2 dup (?), EOS SwitCh db '-' ; char introducing options HFlag db 0 ; flag for on-line help DFlag db 0 ; flag for displaying date NFlag db 0 ; flag for suppressing CR/LF TFlag db 0 ; flag for displaying time MsgLen db 0 ; length of message text MsgTxt dw ? ; near pointer to message text RCode db 0 ; program return code ;--------------------------------------------------------------------------; ; P R O C E D U R E S ; ;--------------------------------------------------------------------------; ;---- put_TwoDigits -----------------------------------------------------; ; Purpose: Displays a number between 0 and 99 on STDOUT with a leading ; ; 0 as necessary. ; ; Notes: No validity checks are done. ; ; Entry: AL = number to display. ; ; Exit: n/a ; ; Calls: utoa, putchar, fputs ; ; Changes: [TwoDigits] ; ;--------------------------------------------------------------------------; PROC put_TwoDigits push ax bx dx di ZERO ah mov bx, STDOUT mov di, OFFSET TwoDigits call utoa ; treat it as unsigned int cmp al, 9 ; need a leading 0? ja SHORT @@WriteIt mov dl, '0' call putchar @@WriteIt: mov dx, di call fputs pop di dx bx ax ret ENDP put_TwoDigits ;---- skip_Spaces -------------------------------------------------------; ; Purpose: Skips past spaces in a string. ; ; Notes: Scanning stops with either a non-space *OR* CX = 0. ; ; Entry: DS:SI = start of string to scan. ; ; Exit: AL = next non-space character, ; ; CX is adjusted as necessary, ; ; DS:SI = pointer to next non-space. ; ; Calls: none ; ; Changes: AL, CX, SI ; ;--------------------------------------------------------------------------; PROC skip_Spaces jcxz SHORT @@Fin @@NextCh: lodsb cmp al, ' ' loopz @@NextCh jz SHORT @@Fin ; CX = 0; don't adjust inc cx ; adjust counters if cx > 0 dec si @@Fin: ret ENDP skip_Spaces ;---- get_Opt -----------------------------------------------------------; ; Purpose: Get a commandline option. ; ; Notes: none ; ; Entry: AL = option character, ; ; Exit: n/a ; ; Calls: tolower, errmsg ; ; Changes: AX, DX, ; ; [OptCh], [HFlag], [DFlag], [NFlag], [TFlag], ; ;--------------------------------------------------------------------------; PROC get_Opt mov [OptCh], al ; save for later call tolower ; use only lowercase in cmp. cmp al, 'd' jz SHORT @@OptD cmp al, 'n' jz SHORT @@OptN cmp al, 't' jz SHORT @@OptT cmp al, '?' jz SHORT @@OptH mov dx, OFFSET Err1Msg ; unrecognized option call errmsg ; then *** DROP THRU *** to OptH ; ; Various possible options. ; @@OptH: mov [HFlag], 1 ; set help flag jmp SHORT @@Fin @@OptD: mov [DFlag], 1 ; display date jmp SHORT @@Fin @@OptN: mov [NFlag], 1 ; no final CR/LF jmp SHORT @@Fin @@OptT: mov [TFlag], 1 ; display time @@Fin: ret ENDP get_Opt ;---- get_Arg -----------------------------------------------------------; ; Purpose: Gets a non-option from the set of commandline arguments. ; ; Notes: Anything left on the commandline is user's message text. ; ; Entry: CX = count of characters left in commandline, ; ; DS:SI = pointer to argument to process. ; ; Exit: CX = zero ; ; DS:SI = points to CR after commandline. ; ; Calls: none ; ; Changes: CX, SI ; ; [MsgLen], [MsgTxt] ; ;--------------------------------------------------------------------------; PROC get_Arg mov [MsgLen], cl ; for safekeeping mov [MsgTxt], si add si, cx ; adjust so nothing's left ZERO cl mov [BYTE PTR si], EOS ; finish off string ret ENDP get_Arg ;---- process_CmdLine ---------------------------------------------------; ; Purpose: Processes commandline arguments. ; ; Notes: A switch character by itself is ignored. ; ; No arguments whatsoever causes help flag to be set. ; ; Entry: n/a ; ; Exit: n/a ; ; Calls: skip_Spaces, get_Opt, get_Arg ; ; Changes: AX, CX, SI, ; ; DX (get_Opt), ; ; [DFlag], [TFlag], ; ; [OptCh], [NFlag] (get_Opt), ; ; [MsgLen], [MsgTxt] (get_Arg), ; ; Direction flag is cleared. ; ;--------------------------------------------------------------------------; PROC process_CmdLine cld ; forward, march! ZERO ch mov cl, [CmdLen] ; length of commandline mov si, OFFSET CmdLine ; offset to start of commandline call skip_Spaces ; check if any args supplied or cl, cl jnz SHORT @@ArgLoop ; yep mov [DFlag], 1 ; nope, so display date ... mov [TFlag], 1 ; and time jmp SHORT @@Fin ; ; For each blank-delineated argument on the commandline... ; @@ArgLoop: lodsb ; next character dec cl cmp al, [SwitCh] ; is it the switch character? jnz SHORT @@NonOpt ; no ; ; Isolate each option and process it. Stop when a space is reached. ; @@OptLoop: jcxz SHORT @@Fin ; abort if nothing left lodsb dec cl cmp al, ' ' jz SHORT @@NextArg ; abort when space reached call get_Opt jmp @@OptLoop ; ; Process the current argument, which is *not* an option. ; Then, *drop thru* to advance to next argument. ; @@NonOpt: dec si ; back up one character inc cl call get_Arg ; ; Skip over spaces until next argument is reached. ; @@NextArg: call skip_Spaces or cl, cl jnz @@ArgLoop @@Fin: ret ENDP process_CmdLine ;--------------------------------------------------------------------------; ; E N T R Y P O I N T ; ;--------------------------------------------------------------------------; ;---- main --------------------------------------------------------------; ; Purpose: Main section of program. ; ; Notes: none ; ; Entry: Arguments as desired ; ; Exit: Return code as follows: ; ; 0 => program ran successfully ; ; 1 => on-line help requested ; ; Calls: process_CmdLine, fputs, putchar, getdate, put_TwoDigits, ; ; gettime ; ; Changes: n/a ; ;--------------------------------------------------------------------------; main: ; ; Process commandline arguments. If the variable HFlag is set, then ; on-line help is displayed and the program immediately terminates. ; call process_CmdLine ; process commandline args cmp [HFlag], 0 ; is help needed? jz SHORT @@NoHelp ; no mov [RCode], ERRH ; yes, so set return code mov bx, STDERR mov dx, OFFSET HelpMsg ; point to help message call fputs ; display it jmp SHORT @@Fin ; and jump to end of program ; ; Display any message from commandline then get keypress from user. ; @@NoHelp: mov bx, STDOUT ; everything to stdout cmp [MsgLen], 0 ; anything to print out? jz SHORT @@Date? ; nope mov dx, [MsgTxt] ; display message text call fputs mov dl, ' ' ; and a space call putchar @@Date?: cmp [DFlag], 0 jz SHORT @@Time? call getdate mov al, dh ; dh = month call put_TwoDigits mov al, dl ; dl = day mov dl, DATE_SEP ; now we can use dl for DATE_SEP call putchar call put_TwoDigits call putchar ; dl still holds DATE_SEP mov ax, cx ; cx = year sub ax, 1900 ; assume 20th century call put_TwoDigits mov dl, ' ' call putchar @@Time?: cmp [TFlag], 0 ; display time? jz SHORT @@FinalEOL? ; no call gettime mov al, ch ; ch = hour call put_TwoDigits mov dl, TIME_SEP call putchar mov al, cl ; cl = minutes call put_TwoDigits @@FinalEOL?: cmp [NFlag], 0 ; suppress final CR/LF? jnz SHORT @@Fin ; no mov dx, OFFSET EOL+1 call fputs ; ; Ok, let's terminate the program and exit with proper return code. ; @@Fin: mov al, [RCode] mov ah, 4ch int DOS EVEN Buffer db ? ; space for single character ; nb: shared by fgetc() & fputc() ;-------------------------------------------------------------------------; ; Purpose: Reads a character from specified device. ; Notes: No checks are done on BX's validity. ; Buffer is shared by fputc(). Do *NOT* use in a ; multitasking environment like DESQview. ; Requires: 8086-class CPU and DOS v2.0 or better. ; Entry: BX = device handle. ; Exit: AL = character, ; Carry flag set on error (AX holds error code). ; Calls: none ; Changes: AX ; flags ;-------------------------------------------------------------------------; PROC fgetc push cx dx IF @DataSize NE 0 push ds mov ax, @data mov ds, ax ENDIF mov dx, OFFSET Buffer ; point to storage mov cx, 1 ; only need 1 char mov ah, 3fh int DOS ; get it jc SHORT @@Fin ; abort on error mov al, [Buffer] @@Fin: IF @DataSize NE 0 pop ds ENDIF pop dx cx ret ENDP fgetc ;-------------------------------------------------------------------------; ; Purpose: Writes a character to specified device. ; Notes: No checks are done on BX's validity. ; Buffer is shared by fputc(). Do *NOT* use in a ; multitasking environment like DESQview. ; Requires: 8086-class CPU and DOS v2.0 or better. ; Entry: AL = character to display, ; BX = device handle. ; Exit: AL = 1 if successful, ; Carry flag set on error (AX holds error code). ; Calls: none ; Changes: AX ;-------------------------------------------------------------------------; PROC fputc push cx dx IF @DataSize NE 0 push ds mov dx, @data mov ds, ax ENDIF mov dx, OFFSET Buffer ; point to storage mov [Buffer], al ; save char mov cx, 1 ; only write 1 char mov ah, 40h int DOS IF @DataSize NE 0 pop ds ENDIF pop dx cx ret ENDP fputc ;-------------------------------------------------------------------------; ; Purpose: Reads a character from STDIN. ; Notes: Character is echoed to display. ; Requires: 8086-class CPU and DOS v1.0 or better. ; Entry: n/a ; Exit: AL = character. ; Calls: none ; Changes: AX ;-------------------------------------------------------------------------; PROC getchar mov ah, 1 int DOS ret ENDP getchar ;-------------------------------------------------------------------------; ; Purpose: Writes a character to STDOUT device. ; Notes: none ; Requires: 8086-class CPU and DOS v1.0 or better. ; Entry: DL = character to display. ; Exit: n/a ; Calls: none ; Changes: none ;-------------------------------------------------------------------------; PROC putchar push ax mov ah, 2 int DOS pop ax ret ENDP putchar ;-------------------------------------------------------------------------; ; Purpose: Checks if a character is ready for input from STDIN. ; Notes: none ; Requires: 8086-class CPU and DOS v1.0 or better. ; Entry: n/a ; Exit: zf = 1 if character available. ; Calls: none ; Changes: flags ;-------------------------------------------------------------------------; PROC kbhit push ax mov ah, 0bh int DOS cmp al, 0ffh ; AL = FFh if character ready pop ax ret ENDP kbhit EVEN ;-------------------------------------------------------------------------; ; Purpose: Writes an ASCIIZ string to specified device. ; Notes: A zero-length string doesn't seem to cause problems when ; this output function is used. ; Requires: 8086-class CPU and DOS v2.0 or better. ; Entry: BX = device handle, ; DS:DX = pointer to string. ; Exit: Carry flag set if EOS wasn't found or handle is invalid. ; Calls: strlen ; Changes: none ;-------------------------------------------------------------------------; PROC fputs push ax cx di es mov ax, ds mov es, ax mov di, dx call strlen ; set CX = length of string jc SHORT @@Fin ; abort if problem finding end mov ah, 40h ; MS-DOS raw output function int DOS @@Fin: pop es di cx ax ret ENDP fputs EVEN ;-------------------------------------------------------------------------; ; Purpose: Writes an error message to stderr. ; Notes: none ; Requires: 8086-class CPU and DOS v2.0 or better. ; Entry: DS:DX = pointer to error message. ; Exit: n/a ; Calls: fputs ; Changes: none ;-------------------------------------------------------------------------; PROC errmsg push bx dx mov bx, STDERR mov dx, OFFSET ProgName ; display program name call fputs pop dx ; recover calling parameters push dx ; and save again to avoid change call fputs ; display error message mov dx, OFFSET EOL call fputs pop dx bx ret ENDP errmsg EVEN ;-------------------------------------------------------------------------; ; Purpose: Gets current system date, based on DOS's internal clock. ; Notes: none ; Requires: 8086-class CPU and DOS v1.0 or better. ; Entry: n/a ; Exit: AL = day of week (0 = Sunday) ; DL = day (1 to 31) ; DH = month (1 to 12) ; CX = year (1980 to 2099) ; Calls: none ; Changes: AX, CX, DX ;-------------------------------------------------------------------------; PROC getdate mov ah, 2ah ; MS-DOS get system date function int DOS ret ENDP getdate ;-------------------------------------------------------------------------; ; Purpose: Gets current system time, based on DOS's internal clock. ; Notes: none ; Requires: 8086-class CPU and DOS v1.0 or better. ; Entry: n/a ; Exit: CL = minutes (0 - 59) ; CH = hour (0 - 23) ; DL = hundredths of seconds (0 - 99) ; DH = seconds (0 - 59) ; Calls: none ; Changes: CX, DX ;-------------------------------------------------------------------------; PROC gettime push ax mov ah, 2ch ; MS-DOS get system time function int DOS pop ax ret ENDP gettime EVEN ;-------------------------------------------------------------------------; ; Purpose: Converts an *unsigned* integer in range [0, 65535] to ; an ASCIIZ string of digits. ; Notes: No checks are made to ensure storage area is big enough. ; A terminating null is added. ; Requires: 8086-class CPU. ; Entry: AX = unsigned integer value, ; ES:DI = pointer to string storage area. ; Exit: ES:DI = pointer to start of string. ; Calls: none ; Changes: DI ;-------------------------------------------------------------------------; PROC utoa push ax bx cx dx di mov bx, 10 ; conversion factor ZERO cx ; track # digits in string @@NewDigit: ; for each character ZERO dx ; dx:ax is dividend so make dx 0 div bx ; ax = dx:ax / 10 push dx ; dx = dx:ax mod 10 inc cl ; one more digit processed or ax, ax ; anything left? jnz @@NewDigit @@NextChar: ; for each power of ten pop ax add al, '0' mov [BYTE PTR di], al inc di loop @@NextChar mov [BYTE PTR di], EOS ; don't forget to end it! pop di dx cx bx ax ret ENDP utoa EVEN ;-------------------------------------------------------------------------; ; Purpose: Converts character to lowercase. ; Notes: none ; Requires: 8086-class CPU. ; Entry: AL = character to be converted. ; Exit: AL = converted character. ; Calls: none ; Changes: AL ; flags ;-------------------------------------------------------------------------; PROC tolower cmp al, 'A' ; if < 'A' then done jb SHORT @@Fin cmp al, 'Z' ; if > 'Z' then done ja SHORT @@Fin or al, 20h ; make it lowercase @@Fin: ret ENDP tolower ;-------------------------------------------------------------------------; ; Purpose: Converts character to uppercase. ; Notes: none ; Requires: 8086-class CPU. ; Entry: AL = character to be converted. ; Exit: AL = converted character. ; Calls: none ; Changes: AL ; flags ;-------------------------------------------------------------------------; PROC toupper cmp al, 'a' ; if < 'a' then done jb SHORT @@Fin cmp al, 'z' ; if > 'z' then done ja SHORT @@Fin and al, not 20h ; make it uppercase @@Fin: ret ENDP toupper EVEN ;-------------------------------------------------------------------------; ; Purpose: Calculates length of an ASCIIZ string. ; Notes: Terminal char is _not_ included in the count. ; Requires: 8086-class CPU. ; Entry: ES:DI = pointer to string. ; Exit: CX = length of string, ; cf = 0 and zf = 1 if EOS found, ; cf = 1 and zf = 0 if EOS not found within segment. ; Calls: none ; Changes: CX, ; flags ;-------------------------------------------------------------------------; PROC strlen push ax di pushf cld ; scan forward only mov al, EOS ; character to search for mov cx, di ; where are we now not cx ; what's left in segment - 1 push cx ; save char count repne scasb je SHORT @@Done scasb ; test final char dec cx ; avoids trouble with "not" below @@Done: pop ax ; get original count sub cx, ax ; subtract current count not cx ; and invert it popf ; restore df dec di cmp [BYTE PTR es:di], EOS je SHORT @@Fin ; cf = 0 if equal stc ; set cf => error @@Fin: pop di ax ret ENDP strlen END