Shareware Grab Bag

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Assembly Source File | 1985-06-03 | 12.9 KB | 410 lines

INCLUDE MACROS.ASM BEGINCOM FILEDIR JMP INIT000 ;GO TO INITIALIZATION CODE ; ; FILE DIRECTOR PROGRAM ; ; ; PATHFLAG DB 0 ;=1=PATH IS AVAILABLE PATH DB 127 DUP (?) ;FILE PATH FILENAME DB 64 DUP (?) CDPREFIX DB 3 DUP (?) ;CURRENT DRIVE PREFIX (IE C:\) CURDIR DB 64 DUP (?) CURDRV DB 0 ;CURRENT DRIVE SAVE SPECTYPE DB 0 ;0=HANDLE, 1 = FCB TYPE I/O FCBDRIVE DB 0 ;ORIGINAL FCB DRIVE SPECIFIER AXS DW 0 ;INBOUND REGISTER SAVE AREA BXS DW 0 CXS DW 0 DXS DW 0 DSS DW 0 ESS DW 0 SIS DW 0 DIS DW 0 ; ; SETUP FOR FAKE INTERRUPT INTO DOS ; DOS LABEL DWORD DOSOFF DW 0 DOSSEG DW 0 ; ; LIST OF THE DOS COMMANDS WE WANT TO TRAP ; TRAPTABL LABEL BYTE ;DOS CALLS TO TRAP DB 0FH,01H ; FCB OPEN FILE ;********DB 10H,01H ; FCB CLOSE FILE DB 3DH,00H ; HANDLE FILE OPEN TRAPTBLE EQU $ ;END OF TRAP TABLE PGM_ID DB 'File Director V2.0' PGM_IDL EQU ($-PGM_ID) PAGE ;**************************************************************************** ; ; File Director Mainline (All DOS interrupts come here) ; ;**************************************************************************** FDIR000: PUSH DS PUSH CX PUSH BX PUSH AX PUSH CS POP DS ;CS AND DS POINT TO THIS SEGMENT MOV BX,OFFSET TRAPTABL ;POINT TO TABLE OF TRAPS MOV CX,((TRAPTBLE-TRAPTABL)/2) ;ENTRY COUNT IN TABLE FDIR020: CMP AH,[BX] ;DOS CALL = TRAP NUMBER? JE FDIR040 ;YES-WERE OFF AND RUNNING INC BX INC BX LOOP FDIR020 ;CHECK NEXT TRAP ;FALL THRU = PASS CONTROL ON TO DOS POP AX POP BX POP CX POP DS JMP CS:DOS ;TRANSFER CONTROL TO DOS ; ; WE HAVE A FILE OPEN COMMAND - LETS FIND THE DAMN FILE ; FDIR040: MOV AL,[BX+1] ;SAVE WHETHER FCB OR HANDLE TYPE I/O MOV SPECTYPE,AL POP AX POP BX POP CX ;LEAVE DS ON STACK MOV AXS,AX ;SAVE ALL EASILY ACCESSABLE REGS MOV BXS,BX MOV CXS,CX MOV DXS,DX MOV SIS,SI MOV DIS,DI POP AX ;POP INBOUND DS PUSH AX ;AND THEN PUT IT BACK MOV DSS,AX ;SAVE IT MOV AX,ES ;GET INBOUND ES MOV ESS,AX ;SAVE IT ; ; CHECK DRIVE NUMBER ON FCB REQUEST ; CMP SPECTYPE,1 ;FCB OPERATION? JNE FDIR060 ;NO-SKIP THIS MOV BX,DXS ;GET FCB POINTER MOV AX,DSS MOV ES,AX ;ES:BX --> FCB CMP BYTE PTR ES:[BX],0FFH ;EXTENDED FCB? JNE FDIR050 ;NO-A REGULAR FCB ADD BX,7 ;MAKE BX --> DRIVE BYTE FDIR050: MOV AL,ES:[BX] ;GET DRIVE ASSIGNMENT MOV FCBDRIVE,AL ;SAVE DRIVE ; ;STACK HAS INBOUND DS ON TOP ; ; SEE IF THE FILE WILL OPEN 'AS IS' (IN THE CURRENT DIRECTORY/PATH) ; FDIR060: MOV AX,AXS ;RESTORE DOS COMMAND POP DS ;RESTORE INBOUND DS PUSHF ;FAKE AN INTERRUPT INSTR CALL CS:DOS ;CALL DOS FOR OPEN PUSH DS ;SAVE INBOUND DS PUSH AX ;SAVE DOS RETURN VALUE PUSHF ;SAVE CARRY FLAG FOR HANDLE I/O PUSH CS POP DS ;MAKE OUR SEGMENT ADDRESSABLE CMP PATHFLAG,0 ;IS THERE A PATH TO CHASE? JE FDIR090 ;NO-RETURN TO APPLICATION CMP SPECTYPE,0 ;IS THIS A COMMAND TO OPEN WITH A HANDLE JNE FDIR080 ;NO-ITS AN FCB ; ; HANDLE OPS - INITIAL TRY ; POPF PUSHF ;SAVE FLAGS AGAIN JNC FDIR090 ;IF IT OPENED, GO BACK TO APPLICATION CMP AX,2 ;FILE NOT FOUND ERROR JNE FDIR090 ;NO-A DIFFERENT ERROR, RET TO APPLICATION JMP FDIR100 ;LETS GO INTO THE PATH CHASE CODE FDIR080: ; ; FCB OPS - INITIAL TRY ; OR AL,AL ;FILE OPEN OK? JNZ FDIR400 ;NO-GO TO FCB CHASE FDIR090: JMP FDIR800 ;** TST ** FOR NOW - JUST ABORT ON FCB'S PAGE ;**************************************************************************** ; ; File Director HANDLE chase code STACK HAS FLAGS, AX, THEN INBOUND DS ; ;**************************************************************************** FDIR100: POP AX ;REMOVE FLAGS AND AX FROM STACK POP AX ;LEAVE DS ON THERE MOV SI,OFFSET PATH FDIR120: CALL BLDNAME ;BUILD FILENAME IN FILENAME AREA ; ; LETS TRY OPENING WITH THIS PATH ; MOV DX,OFFSET FILENAME ;DS:DX POINT TO FILENAME MOV AX,AXS ;GET DOS OPEN COMMAND PUSHF CALL DOS ;TRY TO OPEN PUSH AX PUSHF ;SAVE DOS RETURNED FLAGS JNC FDIR190 ;OPENED-RETURN TO APPLICATION ; ; OPEN FAILED - TRY NEXT PATH IF ANY ; FDIR160: CMP BYTE PTR [SI],0 ;ALL POSSIBILITIES TRIED? JE FDIR190 ;YES-GIVE UP INC SI ;ELSE-BUMP PAST SEP CHARACTER POP AX POP AX ;POP DOS FLAGS AND RETURN CODE OFF STK JMP FDIR120 ;AND GO BUILD ANOTHER NAME FDIR190: POP BX ;POP FLAGS OFF POP AX ;GET HANDLE OR ERROR CODE PUSH BX POPF ;GET OLD FLAGS TO TEST JNC FDIR195 ;IF NO ERROR-SKIP ALTER ERROR CODE CMP AX,3 ;INVALID PATH? JNE FDIR195 ;NO-RETURN TO APPL DEC AX ;CONVERT TO FILE NOT FOUND FDIR195: PUSH AX PUSH BX ;PUSH AX & FLAGS BACK JMP FDIR800 ;RETURN TO APPLICATION ;**************************************************************************** ; ; File Director FCB chase code STACK HAS FLAGS, AX, THEN INBOUND DS ; ;**************************************************************************** FDIR400: FDIR410: CMP FCBDRIVE,0 ;GENERIC DRIVE REQUEST? JE FDIR420 ;YES-GO CHASE IT JMP FDIR800 ;SPECIFIC DRIVE REQUESTED-RETURN ERROR ; ; ; FDIR420: POPF POP AX ;REMOVE FLAGS & RET CODE FROM STACK MOV SI,OFFSET PATH FDIR440: CALL BLDPATH ;SET UP A NEW PATH MOV BX,WORD PTR FILENAME MOV WORD PTR CDPREFIX,BX ;COPY PREFIX MOV CDPREFIX+2,'\' ;CURRENT DIRECTORY PREFIX SET UP MOV DL,FILENAME ;GET DRIVE LETTER SUB DL,'A' ;INDEX (A=1,B=2,ETC) INC DL PUSH SI ;SAVE PATH POINTER MOV SI,OFFSET CURDIR ;CURRENT DIRECTORY SAVE AREA MOV AH,47H ;GET CURRENT DIRECTORY COMMAND PUSHF ;FAKE AN INTERRUPT CALL CS:DOS ;CALL DOS FOR THIS ; ;CURRENT DIRECTORY IS AT CURDIR FOR RESTORE POP SI ;RESTORE PATH POINTER MOV DX,OFFSET FILENAME ;POINT TO FILE NAME AREA (CONTAINS PATH) MOV AH,3BH ;CHANGE CURRENT DIRECTORY PUSHF ;FAKE AN INTERRUPT CALL CS:DOS ;CALL DOS FOR THIS JC FDIR500 ;IF ERROR-TRY NEXT PATH MOV BX,DXS ;GET FCB POINTER MOV AX,DSS MOV ES,AX ;ES:BX --> FCB CMP BYTE PTR ES:[BX],0FFH ;EXTENDED FCB? JNE FDIR450 ;NO-A REGULAR FCB ADD BX,7 ;MAKE BX --> DRIVE BYTE FDIR450: MOV AL,FILENAME ;GET DRIVE LETTER FOR THIS PATH SUB AL,'A' ;FIX UP FOR CHARACTER FORMAT INC AL ;+1 SINCE DRIVE A = 1 MOV BYTE PTR ES:[BX],AL ;RESET DRIVE BASED ON PATH MOV AX,AXS ;GET DOS COMMAND MOV DX,DXS POP DS ;DS:DS --> FCB PUSHF ;FAKE AN INT INSTRUCTION CALL CS:DOS ;TRY TO OPEN PUSH DS PUSH AX PUSHF ;SAVE REGS FOR RETURNING PUSH CS POP DS ;RESTORE OUR OWN DS CMP AL,0 ;OPEN OK? JE FDIR600 ;YES-APPLICATION RETURN ; ; OPEN FAILED - TRY NEXT PATH ; FDIR500: CMP BYTE PTR [SI],0 ;HAVE ALL PATHS BEEN SEARCHED? JE FDIR600 ;YES RETURN TO APPL ; ;RESTORE THE OLD 'CURRENT DIRECTORY' MOV DX,OFFSET CDPREFIX ;POINT TO SAVED CURRENT DIRECTORY INFO MOV AH,3BH ;CHANGE CURRENT DIRECTORY PUSHF ;FAKE AN INTERRUPT CALL CS:DOS ;CALL DOS FOR THIS INC SI ;PAST SEPERATOR CHAR POP AX POP AX ;REMOVE FLAGS & AX FROM STACK JMP FDIR440 ;AND TRY ANOTHER PATH ; ; RESET THE ORIGINAL DIRECTORY IN USE BEFORE FILE OPENED ; FDIR600: MOV DX,OFFSET CDPREFIX ;POINT TO SAVED CURRENT DIRECTORY INFO MOV AH,3BH ;CHANGE CURRENT DIRECTORY PUSHF ;FAKE AN INTERRUPT CALL CS:DOS ;CALL DOS FOR THIS ; ; ; RETURN TO APPLICATION WHETHER SUCESSFUL OR NOT ; FDIR800: ;RETURN TO APPLICATION AFTER SEARCH ; ; RETURN TO APPLICATION ; MOV AX,ESS MOV ES,AX MOV BX,BXS MOV CX,CXS MOV DX,DXS MOV SI,SIS MOV DI,DIS ;RESTORE BX,CX,DX,SI,DI POPF ;RESTORE DOS RETURN FLAGS POP AX ;RESTORE DOS RETURN CODE/HANDLE POP DS ;POP USERS DS DUMMY PROC FAR RET 2 ;RETURN TO APPLICATION W/ DOS FLAGS DUMMY ENDP PAGE ;****************************************************************************** ; ; BUILD FILE NAME IN FILENAME AREA. SI POINTS TO CURRENT SPOT IN PATH LIST ; ;****************************************************************************** BLDNAME PROC NEAR CALL BLDPATH ; NEW PATH BUILT, APPEND FILE NAME ; DEC DI ;POINT TO LAST PATH CHARACTER CMP BYTE PTR [DI],'\' ;IS THERE A SEPERATOR? JE BLDN120 ;YES-THEN READY FOR FILE NAME INC DI MOV BYTE PTR [DI],'\' ;ELSE-INSTALL SEPERATOR BLDN120: INC DI ;POINT TO NEXT AVAILABLE FILENAME BYTE MOV BX,DXS ;BX HAS OFFSET OF FILE NAME MOV AX,DSS ;GET INBOUND DS MOV ES,AX ;INTO ES BLDN140: MOV AL,ES:[BX] ;GET CHAR FROM FILE NAME MOV [DI],AL ;SAVE FOLLOWING THE NEW PATH INC BX INC DI ;BUMP POINTERS CMP AL,0 ;AT END OF FILENAME? JNE BLDN140 ;NO-KEEP MOVING RET BLDNAME ENDP ; ; ; BLDPATH PROC NEAR BLDN100: MOV DI,OFFSET FILENAME BLDP120: MOV AL,[SI] ;GET A PATH CHARACTER CMP AL,';' ;PATH COMPLETE? JE BLDP140 ;YES-TRY OPENING UP CMP AL,0 ;END OF POSSIBLE PATHS JE BLDP140 ;YES-TRY OPEN (LAST POSSIBLE TRY) MOV [DI],AL ;SAVE PATH CHARACTER INC DI INC SI JMP BLDP120 ;BUILD COMPLETE PATH BLDP140: MOV BYTE PTR [DI],0 ;NOW HAVE AN ASCIIZ PATH RET BLDPATH ENDP ENDRES EQU $ PAGE ; ; NON-RESIDENT CODE ; DONEMSG DB 13,10,'FILE-DIRECTOR PATH SET UP',13,10,'$' PATHMSG DB 13,10,'CURRENT PATH:',13,10,'$' NONEMSG DB '==NONE==',13,10,'$' RESFLAG DB 0 ;ASSUME ALREADY RESIDENT INIT000: @DOS 35H,21H ;GET DOS'S OWN INTERRUPT VECTOR MOV DI,OFFSET PGM_ID ;POINT TO NAME IN RESIDENT PGM (IF ANY) MOV SI,DI ;OFFSET THE SAME IN THIS PROGRAM MOV CX,PGM_IDL ;LENGTH TO COMPARE REP CMPSB ;IS FILE DIRECTOR RESIDENT? JE INIT100 ;YES-DONT KEEP RESIDENT PUSH DS POP ES ;RESTORE ES POINTING TO THIS SEGMENT MOV RESFLAG,1 ;NOT RESIDENT - POINTERS ARE SET UP TO LOAD INIT100: SUB DX,DX ;ACTUAL CHARACTER COUNT MOV SI,80H ;ADDRESS OF PARM LENGTH COUNT SUB CH,CH MOV CL,[SI] ;BYTES TO MOVE MOV DI,OFFSET PATH ;POINT TO INPUT PATH ES POINTS TO STORAGE OR CX,CX ;ANY BYTES INPUT? JZ INIT920 ;NO-DISPLAY PATH INIT120: INC SI ;POINT TO CHARACTER TO MOVE MOV AL,[SI] ;GET A CHAR CMP AL,' ' ;BLANK? JE INIT140 ;YES-DISCARD MOV ES:[DI],AL ;ELSE-SAVE IT INC DI ;BUMP 'FROM' POINTER INC DX ;CHARACTER MOVED COUNTER INIT140: LOOP INIT120 OR DX,DX ;ALL BLANK? JZ INIT920 ;YES-DISPLAY PATH MOV ES:PATHFLAG,1 ;ASSUME VALID PATH CMP DL,1 ;SINGLE CHARACTER? JNE INIT160 ;NO-THEN PROBABLY A GOOD PATH CMP AL,';' ;SINGLE SEMICOLON? JNE INIT160 ;NO-AN INVALID BUT ACCEPTABLE PATH MOV ES:PATHFLAG,0 ;SET NO PATH AVAILABLE INIT160: JZ INIT920 ;YES-DISPLAY CURRENT PATH MOV BYTE PTR ES:[DI],0 ;MAKE IT AN ASCIIZ STRING MOV DX,OFFSET DONEMSG @DOS 9 ;SEND DONE MESSAGE CMP RESFLAG,1 ;NEED TO KEEP IN CORE? JE INIT400 ;YES-SET DOS INTERRUPT VECTOR INT 20H ;ELSE - JUST SAY GOODBYE INIT400: SUB AX,AX MOV ES,AX ;ADDRESS LO CORE (DONT CHANGE INT 21 W/DOS) MOV BX,21H*4 ;ES:BX --> VECTOR FOR DOS MOV AX,ES:[BX] ;GET DOS'S OFFSET MOV DOSOFF,AX MOV AX,ES:[BX+2] ;GET DOS'S SEGMENT MOV DOSSEG,AX ;POINTER INTO DOS IS SET MOV AX,OFFSET FDIR000 ;OFFSET TO THE FILE DIRECTOR MAINLINE CLI ;CANT HAVE INTS DURING VECTOR UPDATE MOV ES:[BX],AX ;UPDATE DOS OFFSETT MOV AX,CS ;NEW SEGMENT FOR DOS INT 21H MOV ES:[BX+2],AX ;UPDATE DOS SEGMENT STI ;INTS OK NOW MOV DX,OFFSET ENDRES ;POINT TO END OF RESIDENT CODE INIT900: INT 27H ;STAY RESIDENT ; ; DISPLAY CURRENT PATH ES:DI --> PATH ; INIT920: MOV DX,OFFSET PATHMSG @DOS 9 MOV AL,ES:PATHFLAG ;IS THERE A PATH OR AL,AL JNZ INIT930 ;YES-DISPLAY IT MOV DX,OFFSET NONEMSG @DOS 9 ;DISPLAY '==NONE==' INT 20H ;ABORT INIT930: MOV DL,ES:[DI] ;GET PATH CHARACTER OR DL,DL ;END? JZ INIT960 ;YES-APPEND CR/LF @DOS 2 ;DISPLAY CHAR INC DI JMP INIT930 ;DO NEXT INIT960: MOV DL,13 ;ADD CR/LF @DOS 2 MOV DL,10 @DOS 2 INT 20H ;ALL DONE ENDCOM FILEDIR