Simtel MSDOS 1992 June

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/ Simtel MSDOS 1992 June / SIMTEL_0692.cdr / msdos / pcmag / vol5n16.arc / XDEL.ASM next >

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Assembly Source File | 1987-12-13 | 17.0 KB | 363 lines

TITLE XDEL.ASM SCANS CURRENT DIRECTORY ALLOWING FILE DELETION. ; COMMAND LINE SPECIFIES FILE MATCHING MASK ; DOS EQU 21H ;DOS FUNC INTERRUPT VIDEO EQU 10H ;BIOS VIDEO INTERRUPT CSEG SEGMENT ASSUME CS:CSEG, DS:CSEG, ES:CSEG, SS:CSEG ORG 80H PARM LABEL BYTE ;UNFORMATTED AREA OF PSP ORG 9EH FNAME LABEL BYTE ;FILE NAME RETURNED IN DTA ; WITHIN PSP BY 4EH CALL ORG 100H ENTRY: JMP BEGIN ;SKIP OVER DATA DB "Copyright 1986 Ziff-Davis Publishing Co.",1Ah APAGE DB 0 ;CURRENT VIDEO PAGE db 'ATTR=' ;PATCH POINT TO PRESET ATTR DB 0 ; SCREEN ATTRIBUTE COUNT DB 0 ;COUNT FILE NAMES DELIM DB 9,' ,;=' ;COMMAND LINE DELIMITERS DRIVE_NO DB ? ;DISK DRIVE (0=A, ETC) DRIVE_SPEC DB 3 DUP(0) ;DRIVE LETTER & ":" PATH_SPEC DB '\',65 DUP(0),0 ;CURRENT DIRECTORY ; FILE NAME MASK DELETE_PATH DB 14 DUP(0),0 ;NAME OF FILE TO DELETE MATCH_PATH DB 'A:*.*',9 DUP(0),0 ;FILE MATCH STRING INSTR DB 13,10,10,'Home - first file match ',9,9,9 DB 'PgDn - next file match ',13,10 DB 'F1 - delete last file shown',9,9,9 DB 'ESC - back to DOS',13,10 DB 80 DUP(205),13,0 HDR DB 9,9,9,' DIRECTORY PURGE UTILITY',13,10 DB 'Current Directory :',13,10,0 PATH_MSG DB 16,' ',0 ;RIGHT ARROW NOT_FOUND DB 13,10,'File not found',0 BAD_SPEC DB 13,10,'Invalid drive / file specification',13,10 DB 'Change directory before using XDEL',0 SPEC_ERROR: MOV DX,OFFSET BAD_SPEC ;ERROR MSG CALL PRT_ASCIIZ ;PRINT ERROR INT 20H ;RETURN TO DOS BEGIN: MOV AH,8 ;GET CHAR/ATTR AT CURSOR POS INT VIDEO ;BIOS CALL MOV APAGE,BH ;BH = ACTIVE PAGE CMP ATTR,0 ;ATTRIBUTE PRESET? JNE SCAN_CMD ;YES, USE SPECIFIED ATTR MOV ATTR,AH ;NO, SAVE CURRENT ATTR ; ;SEARCH UNFORMATTED AREA OF PSP FOR FILE NAME SPECIFICATION ;TO USE IN FILE MATCH COMPARISON ; SCAN_CMD: CLD ;SET DIRECTION FLAG MOV SI,1 + OFFSET PARM ;UNFORMATTED PSP AREA MOV DI,OFFSET DRIVE_SPEC ;DRIVE SPEC AREA SKIP_DELIM: CALL PARM_SCAN ;GET NEXT PARM BYTE JE SKIP_DELIM ;SKIP OVER LEADING DELIMS DEC SI ;POINT TO 1ST BYTE OF SPEC CMP AL,13 ;CARRIAGE RETURN ? JZ GET_DRIVE ;YES, NO PARM SPECIFIED CMP BYTE PTR [SI + 1],':' ;DRIVE SPEC PRESENT? JNZ GET_DRIVE ;NO, GET DEFAULT DRIVE LODSW ;GET DRIVE AND ":" AND AL,0DFH ;CAPITALIZE DRIVE LETTER JMP STORE_DRIVE ;SKIP DEFAULT DRIVE CHECK GET_DRIVE: MOV AH,019H ;GET CURRENT DRIVE (0=A,ETC) INT DOS ; THRU DOS CALL ADD AL,'A' ;CHANGE TO LETTER MOV AH,':' ;DRIVE SPEC SEPARATOR STORE_DRIVE: CMP AL,'A' ;VALID RANGE OF DRIVES JB SPEC_ERROR ; INVALID DRIVE CMP AL,'Z' JA SPEC_ERROR STOSW ;SAVE DRIVE SPEC AND ":" MOV DI,OFFSET DELETE_PATH ;DELETE RTN PATH STOSW ;LOAD DRIVE MOV DI,OFFSET MATCH_PATH ;FILE MATCHING PATH STOSW ;LOAD DRIVE SUB AL,'A' ;CHG DRIVE TO NUM (0=A, ETC) MOV DRIVE_NO,AL ;SAVE DRIVE CMP BYTE PTR [SI],13 ;CARRIAGE RETURN ? JE GLOBAL_SCAN ;YES, SCAN *.* MOV CX,12 ;MAX LENGTH FILE SPEC PARSE: CALL PARM_SCAN ;GET NEXT PARM BYTE JE PARSE ;SKIP DELIMS CMP AL,13 ;CARRIAGE RETURN? JE END_SPEC ;YES, END OF FILE SPEC CMP AL,'\' ;PATH SPECIFIED? JE SPEC_ERROR ;YES, ERROR STOSB ;MOVE BYTE TO MATCH PATH DEC CX ;COUNT FILE SPEC LENGTH JCXZ END_SPEC ;IF CX = 0, STOP BUILD JMP PARSE END_SPEC: MOV BYTE PTR [DI],0 ;TRAILING ZERO GLOBAL_SCAN: CALL GET_PATH ;GET PATH FOR DRIVE SPEC RESTART: CALL CLR_SCR ;CLEAR SCREEN MOV DX,OFFSET HDR ;SCREEN TITLE LINE CALL PRT_ASCIIZ ; AND PRINT MOV DX,OFFSET PATH_MSG ;DIRECTORY INFO MSG CALL PRT_ASCIIZ ; AND PRINT MOV DX,OFFSET DRIVE_SPEC ;DRIVE/PATH/FILE CALL PRT_ASCIIZ ; AND PRINT MOV DX,OFFSET PATH_SPEC ;PATH_SPEC CALL PRT_ASCIIZ ; AND PRINT MOV DX,OFFSET MATCH_PATH + 2 ;FILE SPEC CALL PRT_ASCIIZ ; AND PRINT MOV DX,OFFSET INSTR ;INSTRUCTION LINE CALL PRT_ASCIIZ ; AND PRINT MOV COUNT,0 ;INITIALIZE FILE COUNTER MOV DX,OFFSET MATCH_PATH ;ADDRESS OF SEARCH MATCH MOV CX,0 ;ATTRIBUTE FOR FILES MOV AH,04EH ;FIND FIRST MATCH INT DOS ; THRU DOS FUNC CALL JC ERROR_RTN ;CARRY SET = ERROR FILE_LOOP: MOV DX,OFFSET FNAME ;POINT TO FILE NAME CALL PRT_ASCIIZ ; AND PRINT ;CX = FILE NAME LENGTH ADD COUNT,1 ;INCREMENT COUNT READ_KYBD: CALL GET_KEY ;GET KEY INSTRUCTION CMP AL,27 ;ESCAPE KEY? JE END_PGM ;YES, END PGM ; ; EXTENDED KEY TESTS ; CMP AL,59 ;FUNC KEY 1? JE DEL_IT ;YES, DELETE FILE CMP AL,71 ;HOME KEY? JE RESTART ;YES, RESTART CMP AL,81 ;PAGE DOWN? JE SKIP_IT ;YES, SKIP TO NEXT FILE JMP READ_KYBD ;NO, IGNORE KEY DEL_IT: PUSH CX ;SAVE FILE NAME LENGTH MOV SI,OFFSET FNAME ;POINT TO FILE NAME MOV DI,OFFSET DELETE_PATH + 2 ;DELETE PATH FILE SPEC MOV CX,13 ;BYTES TO MOVE REP MOVSB ;MOVE FILE NAME POP CX ;RESTORE FILE NAME LENGTH CALL DEL_RTN ;DELETE FILE JC SOUND_ALARM ;CARRY SET - NOT DELETED MOV DL,017 ;"LEFT POINTER" CHAR CALL PRT_CHAR ; AND PRINT INC CX ;INCREMENT STRING COUNT JMP SKIP_IT ;SKIP TO NEXT FILE SOUND_ALARM: MOV DL,07 ;CTRL-G "BEEP" CHAR CALL PRT_CHAR ; PRINT JMP READ_KYBD ;READ KEYBOARD AGAIN SKIP_IT: CALL SPACE_FILL ;POSITION FOR NEXT NAME CALL NEXT_FILE ;FIND NEXT FILE MATCH JC END_PGM ;CARRY SET = NO MORE FILES CMP COUNT,80 ;80 FILE NAMES DISPLAYED? JB FILE_LOOP ;NO, SKIP SCROLL CALL SCROLL_HALF ;SCROLL HALF OF WINDOW SUB COUNT,40 ;SUBTRACT 40 FROM FILE COUNT JMP FILE_LOOP ;KEEP GOING ERROR_RTN: MOV DX,OFFSET NOT_FOUND ;POINT TO MSG CALL PRT_ASCIIZ ; AND PRINT END_PGM: INT 20H ;RETURN TO DOS ;* * * * * * * * * * S U B R O U T I N E S * * * * * * * * * * * * * * * ; ;GET NEXT PARAMTER BYTE AND COMPARE AGAINST DELIMITER TABLE ; ZERO FLAG INDICATES BYTE IN AL IS DELIMITER ; PARM_SCAN: PUSH CX PUSH DI LODSB ;GET BYTE AT DS:[SI] MOV DI,OFFSET DELIM ;POINT TO DELIM STRING MOV CX,5 ;LENGTH OF DELIM STRING REPNE SCASB ;SCAN DELIM UNTIL CX=0 ; OR AL=DS:[DI] POP DI POP CX RET ; ;GET CURRENT DIRECTORY PATH FOR DRIVE SPECIFIED ; GET_PATH: PUSH SI ;SAVE INDEX TO COMMAND LINE MOV AH,047H ;GET CURRENT DIRECTORY MOV DL,DRIVE_NO ;GET DRIVE NUMBER (0=A,ETC) INC DL ;DL = (0=DEFAULT, 1=A, ETC) MOV SI,OFFSET PATH_SPEC + 1 ;SAVE DIRECTORY TO DS:[SI] INT DOS ;DOS CALL SUB AL,AL ;ASCIIZ ZERO BYTE CMP [SI],AL ;CHECK IF ROOT DIR JZ ROOT_DIR ;IF SO, SKIP SEARCH MOV DI,SI ;SCAN PATH FOR HEX 0 MOV CX,64 ;BYTES TO SEARCH REPNZ SCASB ;DO SEARCH FOR TRAILING ZERO DEC DI ;DI POINTS TO END ZERO MOV AL,'\' ;OVERLAY WITH BACK SLASH STOSB ;APPEND TO PATH ROOT_DIR: POP SI ;RESTORE INDEX RET ; ;FINDS NEXT FILE NAME WHICH MATCHES MASK ; NEXT_FILE: PUSH CX MOV DX,OFFSET MATCH_PATH ;ADDRESS OF MATCH STRING MOV CX,0 ;ATTRIBUTE FOR FILES MOV AH,04FH ;FIND NEXT MATCH INT DOS ;DOS FUNC CALL POP CX RET ; ;SPACES OUT FILE NAME TO LENGTH OF 16 BYTES (FIVE NAME PER LINE) ; SPACE_FILL: CMP CX,16 ;PRINTED 16 BYTES? JAE SPC_EXIT ;YES, EXIT MOV DL,' ' ;NO, PRINT SPACE AFTER NAME CALL PRT_CHAR ;PRINT CHAR INC CX ;INCREMENT CX (STRING COUNT) JMP SPACE_FILL ;KEEP GOING SPC_EXIT: RET ; ;PRINTS ASCIIZ STRING POINTED TO BY DS:DX ; CX RETURNS NUMBER OF BYTES PRINTED ; PRT_ASCIIZ: PUSH SI PUSH DX SUB CX,CX ;INIT BYTE COUNT MOV SI,DX ;SET SOURCE INDEX ASC_LOOP: MOV DL,BYTE PTR [SI] ;POINT TO CHAR IN ASCIIZ CMP DL,0 ;FOUND TRAILING ZERO? JZ ASC_EXIT ;YES, EXIT CALL PRT_CHAR ;NO, PRINT CHAR INC SI ;POINT TO NEXT BYTE INC CX ;INCR BYTES PRINTED JMP ASC_LOOP ;KEEP GOING ASC_EXIT: POP DX POP SI RET ; ;PRINTS CHARACTER IN DL ; PRT_CHAR: PUSH AX MOV AH,2 ;PRINT CHAR IN DL INT DOS ;DOS FUNC CALL POP AX RET ; ; ACCEPT ONLY ESCAPE, AND ALL EXTENDED KEY CODES ; GET_KEY: MOV AH,0 ;GET NEXT KEYBOARD CHAR INT 16H ;BIOS CALL CMP AL,27 ;ESCAPE KEY? JE GET_EXIT ;YES, EXIT CMP AL,0 ;EXTENDED KEY? JNZ GET_KEY ;NO, IGNORE XCHG AH,AL ;SWAP SCAN CODE INTO AL GET_EXIT: RET ; ;DELETES FILE NAME IN FIELD "FNAME" ; CARRY FLAG SET - FILE COULD NOT BE DELETED ; CARRY FLAG CLEAR - FILE WAS SUCCESFULLY DELETED ; DEL_RTN: MOV DX,OFFSET DELETE_PATH ;POINT TO DELETE PATH MOV AH,041H ;DELETE FILE FUNC INT DOS ;DOS CALL RET ; ;CLEARS ENTIRE SCREEN AND POSITIONS CURSOR IN UPPER LEFT CORNER ; CLR_SCR: MOV AH,2 ;SET CURSOR POSITION MOV BH,APAGE ;SET CURR PAGE MOV DX,0 ; UPPER LEFT CORNER INT VIDEO ;BIOS CALL MOV BH,ATTR ;ATTRIBUTE TO BH MOV AX,0600H ;SCROLL UP BIOS FUNC MOV CX,0 ;UPPER LEFT WINDOW CORNER MOV DX,1850H ;LOWER RIGHT CORNER 24 X 80 INT VIDEO ;BIOS CALL RET ; ;SCROLLS TOP HALF OF FILE DISPLAY AREA AND POSITIONS CURSOR ON BLANK LINE ; SCROLL_HALF: MOV AH,2 ;SET CURSOR POSITION MOV BH,APAGE ;SET CURR PAGE MOV DX,0F00H ;PUT CURSOR ON LINE 15 INT VIDEO ;BIOS CALL MOV BH,ATTR ;ATTRIBUTE TO BH MOV AX,0608H ;SCROLL UP EIGHT LINES MOV CX,0700H ;UPPER LEFT CORNER OF WINDOW MOV DX,1850H ;LOWER RIGHT CORNER 24 X 80 INT VIDEO ;BIOS CALL RET CSEG ENDS END ENTRY