10 ! DISK CHECKER - DAVE SMALL
13 ! Creative Computing -
15 ! May 1982, pp.186-190
20 !
30 GOTO 290
40 ' SUBROUTINES PLACED IN FRONT
50 ' FOR SPEED, NO COMMENTING.
60 !
70 ' DISK READ SUBROUTINE
80 POKE DCB+1,DFROM
90 POKE DCB+2,82
100 BHI=INT(BUFF/256):BLO=BUFF-(BHI*256)
110 POKE DCB+4,BLO
120 POKE DCB+5,BHI
130 SHI=INT(RSECTOR/256):SLO=RSECTOR-(SHI*256)
140 POKE DCB+10,SLO:POKE DCB+11,SHI
150 X=USR(CALL)
160 DSTATS=PEEK(DCB+3)
170 RETURN
180 ' DISK WRITE SUBROUTINE - (SAMPLE)
190 POKE DCB+1,DTO
200 POKE DCB+2,87
210 BHI=INT(BUFF/256):BLO=BUFF-(BHI*256)
220 POKE DCB+4,BLO
230 POKE DCB+5,BHI
240 SHI=INT(RSECTOR/256):SLO=RSECTOR-(SHI*256)
250 POKE DCB+10,SLO:POKE DCB+11,SHI
260 PRINT "ERROR":GRAPHICS 0
270 DSTATS=PEEK(DCB+3)
280 RETURN
290 REM DISK CHECKER
300 ' DOES SECTOR TRACE OF ALL
310 ' FILES IN THE DIRECTORY.
320 ' PRODUCES LISTING WITH OK/BAD.
330 !
340 ' ASSUMES 48K, MICROSOFT.
350 !
360 ' GET DISK NUMBER, WELCOME.---
370 GRAPHICS 0:SETCOLOR 8,9,4:POKE 82,0:POKE 83,39
380 CLEAR
390 PRINT "          DISK CHECKER          "
400 PRINT:PRINT "INPUT DRIVE NUMBER";
410 INPUT DF$
420 IF DF$="" THEN DFROM=1:GOTO 440
430 DFROM=VAL(DF$)
440 DTO=DFROM
450 CALL=&E453  !DSKINV ADDRESS
460 ! NOTE: MICROSOFT CAN CALL
470 ! DSKINV$ DIRECTLY, NO PLA
480 ! NEEDED
490 DCB=&300
500 OPTION RESERVE 20*128
510 B=VARPTR(RESERVE)
520 IF B<0 THEN B=B+65536
530 ! FIRST, READ IN DIRECTORY----
540 PRINT "GETTING DIRECTORY."
550 INCR=0
560 FOR RSECTOR=360 TO 368
570 BUFF=B+(128*INCR)  !INPUT AREA
580 GOSUB 70           !GET SECTOR
590 IF DSTATS=1 THEN 630
600 PRINT "***DISK RETRY,DIRECTORY SECTOR ";RSECTOR
610 PRINT "***STATUS =";DSTATS
620 GOTO 570
630 INCR=INCR+1
640 PRINT INCR
650 NEXT RSECTOR
660 PRINT
670 PRINT "WAIT -- BUILDING TABLES."
680 ! OK, NOW EXAMINE DIRECTORY.
690 !     PRODUCE LISTING FIRST OFF.
700 !NOTE 360=VTOC, NOT DIR.
710 DIM INFO(64,6)     ! FILE INFO
720 DIM NIME$(64)      ! NAME INFO
730 DIM DEAD(64)       ! FILE BOMBED?
740 FOR Z%=1 TO 64:DEAD(Z%)=0:NEXT Z%
750 '
760 Z=B+128    ! START OF DIR ENTRY
770 ! BUILD FLAG AND INFO TABLE
780 FNUM=1
790 FOR LOC=Z TO Z+(64*16) STEP 16
800 ! LOC=ENTRIES' STARTING ADDR
810 FLAG%=PEEK(LOC)
820 IF(FLAG% AND &80)=&80 THEN INFO(FNUM,3)=1
830 IF(FLAG% AND &40)=&40 THEN INFO(FNUM,4)=1
840 IF(FLAG% AND &20)=&20 THEN INFO(FNUM,5)=1
850 IF (FLAG% AND 1)=1 THEN INFO(NUM,6)=1
860 ! SECTOR INFO-----------------------
870 INFO(FNUM,1)=PEEK(LOC+1)+256*PEEK(LOC+2)
880 INFO(FNUM,2)=PEEK(LOC+3)+256*PEEK(LOC+4)
890 ! NOW GET NAME DATA..---------------
900 NIME$(FNUM)=""
910 FOR Z%=5 TO 15
920 NIME$(FNUM)=NIME$(FNUM)+CHR$(PEEK(LOC+Z%))
930 NEXT Z%
940 ! CHECK FOR END OF ENTRIES
950 IF PEEK(LOC+5)=0 THEN 1020
960 !
970 FNUM=FNUM+1
980 IF FNUM/5=INT(FNUM/5) THEN PRINT FNUM;
990 NEXT LOC
1000 PRINT "DIR TOTALLY FULL."
1010 GOTO 1030
1020 PRINT "DIR PARTLY FULL."
1030 FNUM=FNUM-1
1040 PRINT
1050 PRINT "NUMBER OF ENTRIES =";FNUM
1060 ! OUTPUT DIRECTORY
1070 ! ENTRY POINT FROM BELOW
1080 IF FNUM=0 THEN 1320 ! EMPTY DISK
1090 PRINT
1100 PRINT "  D=DELETED / U=USED / L=LOCKED / O=OPEN"
1110 PRINT " SC=SECTOR COUNT(LEN)"
1120 PRINT " SS=STARTING SECTOR"
1130 PRINT " +=GOOD FILE-=BAD FILE ?=UNKNOWN"
1140 PRINT
1150 FOR F=1 TO FNUM
1160 PRINT USING "##";F;
1170 IF DEAD(F)=-1 THEN PRINT "+";
1180 IF DEAD(F)=1 THEN PRINT "-";
1190 IF DEAD(F)=0 THEN PRINT "?";
1200 PRINT "!";NIME$(F);"!";
1210 IF INFO(F,3)=1 THEN PRINT "D"; ELSE PRINT " ";
1220 IF INFO(F,4)=1 THEN PRINT "U"; ELSE PRINT " ";
1230 IF INFO(F,5)=1 THEN PRINT "L"; ELSE PRINT " ";
1240 IF INFO(F,6)=1 THEN PRINT "O"; ELSE PRINT " ";
1250 PRINT "!SC:";
1260 PRINT USING "###";INFO(F,1);
1270 PRINT "!SS:";
1280 PRINT USING "###";INFO(F,2)
1290 IF F/20=INT(F/20) THEN INPUT RET$
1300 NEXT F
1310 GOTO 1390
1320 PRINT "EMPTY DISK -- NO ENTRIES"
1330 STOP
1340 PRINT
1350 ! ENTRY POINT (BELOW)
1360 PRINT "PRESS RETURN."
1370 INPUT RET$:CLS:GOTO 1420
1380 GOTO 1400
1390 PRINT "PRESS RETURN."
1400 INPUT RET$
1410 ! NEXT IS ENTRY POINT
1420 PRINT "}SELECT :
1430 PRINT "1. 'n' A FILE NUMBER TO CHECK."
1440 PRINT "2. 'A' TO CHECK ALL FILES."
1450 PRINT "3. 'D' TO SEE DIRECTORY LIST AGAIN."
1460 PRINT "NOTE: ERRORS SHOW UP ON DIR LISTING"
1470 PRINT "      AFTER THEY OCCUR IN SEARCH."
1480 INPUT N$
1490 IF N$="A" THEN FILE=128:GOTO 1690
1500 IF N$="D" THEN GRAPHICS 0:GOTO 1070
1510 ON ERROR 1540
1520 FILE=VAL(N$)
1530 GOTO 1560
1540 PRINT "ERROR. RE-ENTER."
1550 RESUME 1420
1560 ! --- PROCESS. CHECK.
1570 IF FILE>FNUM OR FILE<0 OR FILE<>INT(FILE) THEN PRINT "ERROR.":GOTO 1420
1580 ! SINGLE ENTRY HANDLER
1590 PRINT "TRACING--'SELECT' TO ABORT."
1600 SS=INFO(FILE,2)   ! STARTING SECT
1610 SC=INFO(FILE,1)   ! SECTOR COUNT
1620 RSECTOR =SS
1630 ! GO TRACE IT...ARROR=RETURN
1640 GOSUB 1850
1650 IF ARROR=1 THEN PRINT "***BAD FILE***"
1660 IF ARROR=1 THEN DEAD(FILE)=1 ELSE DEAD(FILE)=-1
1670 GOSUB 2110        ! MARK FILE NAME
1680 GOTO 1350
1690 ! ALL ENTRIES HANDLER
1700 FOR FILE=1 TO FNUM
1710 CLS
1720 PRINT "TRACING FILE #";FILE
1730 IF LP=1 THEN PRINT #3,"TRACING FILE #";FILE
1740 PRINT "PRESS 'SELECT' TO ABORT."
1750 SS=INFO(FILE,2) ! STARTING SECT
1760 SC=INFO(FILE,1) ! SECTOR COUNT
1770 RSECTOR=SS
1780 GOSUB 1850
1790 IF ARROR=1 THEN PRINT "***BAD FILE***" **"
1800 IF ARROR=1 THEN DEAD(FILE)=1 ELSE DEAD(FILE)=-1
1810 GOSUB 2110
1820 NEXT FILE
1830 PRINT "COMPLETED."
1840 GOTO 1350
1850 ! TRACING SUBROUTINE
1860 ARROR=0
1870 PRINT
1880 PRINT "---SEC CNT=";SC;" READING SEC ";RSECTOR
1890 POKE &D01F,0      ' CLEAR BUTTONS
1900 GOSUB 70          'READ
1910 ! CHECK BUTTONS
1920 IF PEEK(&D01F)<>7 THEN RETURN
1930 IF DSTATS=1 THEN 1960
1940 PRINT "+++ERROR. DSTATS=";DSTATS;" ON SECTOR ";RSECTOR
1950 GOTO 1900         'RETRY
1960 IF SC=0 THEN RETURN
1970 SC=SC-1           ! DECR S COUNT
1980 ! GET FORWARD POINTER + FNUM
1990 FWD=(PEEK(BUFF+125) AND 3)*256
2000 FWD=FWD+PEEK(BUFF+126)
2010 FN=INT((PEEK(BUFF+125) AND &FC)/4) ! HENCE, SHIFTED 2 BITS RIGHT
2020 FN=FN+1   ! (DISK STARTS AT 0)
2030 PRINT "---DATA: FILE NUM=";FN;"  FWD SEC =";FWD
2040 IF FN<>FILE THEN PRINT "FILE NUMBER ERROR.":ARROR=1
2050 IF FWD>720 OR FWD<0 THEN PRINT "FORWARD PTR OUT OF RANGE, ABORT.:ARROR=1:RETURN
2060 IF FWD=0 THEN 2090
2070 RSECTOR=FWD
2080 GOTO 1870
2090 PRINT "COMPLETED."
2100 RETURN
2110 ! MARK A FILE AS BAD IN NAME.
2120 ! SET HIGH BIT SO IT SHOWS
2130 ! UP IN INVERSE VODEO..
2140 IF ARROR=0 THEN RETURN
2150 Z$=NIME$(FILE)
2160 NIME$(FILE)=""
2170 FOR Z=1 TO LEN(Z$)
2180 NIME$(FILE)=NIME$(FILE)+CHR$((ASC(MID$(Z$,Z,1)) OR &80))  ! SET HIGH BIT
2190 NEXT Z
2200 RETURN