*********************
*
*
*     MOVE DATA
*
*  COME HERE WITH LOCAL COUNT IN DE, GLOBAL IN HL
*
MBLK CALL COMP
 JNC RWP52  DE => HL, USE GLOBAL COUNT
 XCHG .  USE LOCAL COUNT
*
RWP52 CALL CKDEL  CHECK FOR DELIMITER
 MOV B,H
 MOV C,L  COUNT IN BC
*
 LHLD UDE  UPDATE NUMBERS
 DAD B
 SHLD UDE  SOU/DEST ADDRESS
 LHLD UBC
 CALL RWPS
 SHLD UBC  USER COUNT
 LHLD LCNT
 CALL RWPS
 SHLD LCNT  LOCAL COUNT
 LHLD FNBD
 DAD B
 SHLD FNBD  NBD
*
 LHLD SOU
 XCHG .  DE HAS SOURCE
 LHLD DEST  HL HAS DESTINATION
 JMP MOVEV  BC HAS COUNT, MOVE AND RETURN
*
*********************
*
*
*      CHECK FOR DELIMITER
*
*    SET FLAG IF FOUND
*    HL = COUNT
*    RETURN, HL = POSSIBLY REDUCED COUNT, DELFG SET
*
CKDEL LDA DELFG
 ORA A  SEE IF CHECKING FOR DELIMITERS AT ALL
 RZ .  NO
 PUSH H
 XCHG
 LHLD SOU  HL -> DATA, DE = MAX COUNT
*
*  LOOP FOR END OF COUNT OR DELIMITER
*
CKD20 MOV A,D  TEST IF OUT OF COUNT
 ORA E
 JZ CKD30
*
 DCX D  ACCOUNT FOR THIS ONE
 LDA UL  = DELIMITER
 CMP M
 JZ CKD50  FOUND!
 INX H
 JMP CKD20  LOOP
*
*  END OF COUNT... NOT FOUND
*
CKD30 POP H  RESTORE COUNT
 RET
*
*
*  FOUND, COMPUTE UPDATED COUNT
*
CKD50 POP H
 MOV B,D
 MOV C,E  DECREMENTED COUNT IN BC
 CALL RWPS  HL=HL-BC
 MVI A,1
 STA DELFG  SET FLAG
 RET .  ALL SET
*
 PAGE
*
*
*******************************************
*
*
*
*
*                  READ SINGLE BYTE OPERATION
*
*    "A"  HAS THE FILE NUMBER
*
*  THIS OPERATION USES THE USER STACK. THE
*  STANDARD ENTRY AND EXIT ROUTINES ARE NOT USED.
*
*    ERRORS:
*       ILLEGAL FILE NUMBER
*       PROTECTED FILE
*       EOF
*
RB CALL RWPREP  SAVE A BUNCH OF JUNK AND PREPARE
 CALL PROTST  CHECK IF PROTECTED
 DB PREA
*
 JMP RER0  ERROR - PROTECTED
 CALL PBUF  PREPARE BUFFER
*
*  CHECK IF BUFFER EMPTY
*
 LHLD FNBD
 XCHG
 LHLD FBDL  BBD BDL
 CALL COMP  COMPARE DE HL
 JC RB50  NBD LT BDL, OK
*
*  FILL BUFFER
*
 LHLD FBLKS
 CALL RDNB
 JMP RBEOF
*
*  LOAD BYTE AND UPDATE NBD
*
RB50 CALL UPNBD  GET THE BUFFER ADDRESS AND COUNT UP
 MOV A,M
 STA UA  SAVE BYTE
 CALL RBUF  RELEASE BUFFER
 CALL RFCB  RESTORE FCB
 LDA UA  RETURN WITH BYTE IN A
*
*
*  EVERYONE COMES HERE FOR CALL+2
*  RETURN THROUGH HL
*
RP2 POP H
RP3 INX H
 INX H
 INX H
 PCHL .  NORMAL RETURN
*
*
*  PROTECTED
*
RER0 CALL ERRL1
 DB PER0
*
*********************
*
*
*  PREPARE FOR READS AND WRITES
*
RWPREP STA UA  SAVE FILE NUMBER IN USER A
 MOV A,B
 STA UB  WRITE USES THIS
 LXI H,0
 SHLD WBUFSZ  CLEAR DANGLING BUFFER FLAG
 DAD SP
 INX H
 INX H
 SHLD UTOS  SET UTOS FOR ERRORS
 JMP PFCB  PREPARE FCB AND RETURN
*
*
*  UDATE NEXT BYTE DISPLACEMENT AND RETURN BUFFER ADDRESS
*
UPNBD LHLD FNBD  GET NEXT BYTE DISPLACEMENT
 INX H  BUMP IT FOR THIS BYTE
 SHLD FNBD
 DCX H  ADJUST COUNT TO POINT TO CURRENT POSITION
 XCHG
 LHLD TBUFA
 DAD D  HL = NBD + BUFF ADDRESS
 RET
*
 PAGE
*
*
*******************************************
*
*
*
*
*                WRITE SINGLE BYTE OPERATION
*
*  A HAS THE FILE NUMBER
*  B HAS THE BYTE
*
*
*  ON RETURN,
*    A,B ARE UNCHANGED
*
*  THIS OPERATION USES THE USER STACK. STANDARD ENTRY,
*  EXIT, AND ERROR ROUTINES ARE NOT USED
*
*    ERRORS:
*       ILLEGAL FILE NUMBER
*       PROTECTED FILE
*       DISK FULL
*
*
*
WB CALL RWPREP  PREPARE EVERYTHING
 CALL PROTST  CHECK PROTECTION
 DB PWRI
 JMP RER0  ERROR - PROTECTED
 CALL PBUF  PREPARE BUFFER
*
*  CHECK FOR FULL BLOCK
*
 LHLD FNBD
 XCHG
 LHLD FBLKS  NBD BLOCK SIZE
 CALL COMP  COMPARE DE HL
 JC WB50  NBD LT BLOCKSIZE
 CALL WDBR  BUFFER IS FULL...WRITE IT
*
*  STORE BYTE, UPDATE NBD
*
WB50 CALL UPNBD
 LDA UB
 MOV M,A  STORE BYTE
 MVI A,1
 STA FFLAG  SET DIRTY
*
*  UPDATE BDL IF NECESSARY
*
 INX D
 LHLD FBDL  DE HAS NBD
 CALL COMP
 JC WB60  NBD LT BDL, LEAVE BDL ALONE
 XCHG
 SHLD FBDL  UPDATE BOL
*
*  FINISH UP
*
WB60 CALL FDB  FLUSH BUFFER IF DEVICE FILE
 CALL RBUF  RESTORE BUFFER
 CALL RFCB  RESTORE FCB
 LDA UB
 MOV B,A  SET B
 LDA UA  RESTORE A
 JMP RP2
*
 PAGE
*
*
*******************************************
*
*
*
*
*               MOVE FILE POINTER OPERATION (SPACE)
*
*     UA HAS   FILE NUMBER
*     UBC HAS  DELTA VALUE
*     UD= 0    FOR REWIND
*        -1    FOR SPACE-TO-END
*         1    FOR SPACE FOREWARD
*     200(8)   FOR SPACE BACKWARDS
*     UL       DELIMITER IF DSPACE
*
*
*    ERRORS:
*       ILLEGAL FILE NUMBER
*       EOF/BOF
*
*
*  DELIMITER SPACE ENTRY
*
DSPACE MVI A,-1
 JMP SPA01
*
*
*  STANDARD SPACE ENTRY
*
SPACE XRA A
SPA01 STA DELFG  SETUP DELIMITER SCAN FLAG
 CALL PFCB  PREPARE FCB
 CALL PBUF  PREPARE BUFFER
 CALL WDBUF  FLUSH OUT ANYTHING
 LDA UD
 ORA A  LOOK AT OPTIONS
 JNZ SPA20  NOT REWIND
*
*  D=0...REWIND FILE
*
 LHLD FBLKS  GET BLOCK SIZE
 XCHG
 LHLD TBUFA  DE=COUNT, HL->BUFFER
 CALL DVBR  DO THE REWIND
 DB DTREW
*
 SHLD FBDL  GOOD, SET BDL FROM HEADER COUNT
 LXI H,0
 SHLD FNBD
 JMP SPA80
*
*********************
*
*
*  (PART OF DISK INTERFACE)  COME HERE TO REWIND DISK FILE
*
DDREW LHLD FCURSC  CURRENT SECTOR AND TRACK
 XCHG
 LHLD FFBA  FIRST SECTOR AND TRACK
 CALL COMP  CHECK IF CORRECT BLOCK IS IN
 JZ REW10  YES
 SHLD FCURSC  SET AS CURRENT SECTOR
 CALL RBLK  PRIME WITH FIRST BLOCK
 RET .  HL HAS COUNT IN SECTOR
*
*
* CURRENT BLOCK IS IN
*
REW10 LHLD FBDL  RETURN SIZE
 RET
*
*
*   SPACE FORWARD OR BACKWARD
*
SPA20 JP SPAF  (S)HE WANTS FOREWARD
 INR A
 JNZ SPAB  (S)HE WANTS BACKWARDS
*
*  MOVE TO EOF
*
SPA22 LHLD FBLKS
 CALL RDNB  READ NEXT BLOCK
 JMP SPA25  EOF
 JMP SPA22  TRY AGAIN
*
*
SPA25 LHLD FBDL
 SHLD FNBD  SET NBD=BDL
 JMP SPA80  GO QUIT
*
*
*    SPACE FOREWARD
*
SPAF LHLD FNBD
 XCHG .  DE HAS NBD
 LHLD FBDL  HL HAS BDL
 CALL ARITH  HL=HL-DE
 XCHG .  DE HAS BDL-NBD
 CALL UPCNT  GET MAXIMUM COUNT TO HL
 PUSH H
 LHLD TBUFA  COMPUTE -> DATA
 XCHG
 LHLD FNBD
 DAD D  -> DATA
 SHLD SOU  SET DATA SOURCE POINTER
 POP H  GET BACK COUNT
*
*  IF DELIMITED, DO PRESCAN FOR DELIMITER
*
 CALL CKDEL  FIND NEW COUNT IF DELIMITED
 XCHG .  DE HAS MIN OF USER, LOCAL CNT.
 LHLD FNBD
 DAD D
 SHLD FNBD  UPDATE NBD
 LHLD UBC
 CALL ARITH  HL=HL-DE= NEW USER COUNT
 SHLD UBC  UPDATE USER COUNT
*
*  TEST FOR ZERO COUNT OR DELIMITER
*
 ORA L  "A" HAS "H" FROM ARITH
 JZ SPA80  YES, GO QUIT
*
 LDA DELFG  CHECK IF DELIMITER SEEN
 DCR A
 JZ SPA80  YES, GO QUIT
*
*  NO, MOVE TO NEXT BLOCK
*
 CALL RDNB  MOVE TO NEXT
 JMP SEOF  EOF
 JMP SPAF
*
*********************
*
*
*    FIND MIN OF UBC, AND DE INTO HL
*
UPCNT LHLD UBC
 CALL COMP
 RNC .  HL GE DE
 XCHG .  DE LT HL
 RET
*
*********************
*
*    SPACE REVERSE
*
SPAB LHLD FNBD
SPABX XCHG .  DE HAS NBD
 LHLD UBC
 CALL UPCNT  HL GETS MIN OF DE,HL
*
*  HL = MAX COUNT, THIS BUFFER
*  SCAN BACKWARD FOR DEL
*
 LDA DELFG
 ORA A
 JZ SPA69  NO DELIMITER TO LOOK FOR, SKIP THIS JUNK
*
*   CHECK FOR DELIMITER BACKWARDS
*
 PUSH H
 MOV B,H
 MOV C,L  BC = MAX COUNT
 LHLD TBUFA
 XCHG
 LHLD FNBD
 DAD D  HL -> BUFFER END (NEXT CHAR)
*
SPA60 MOV A,B
 ORA C  CHECK FOR ZERO COUNT
 JZ SPA63  YES, END OF BUFFER, NOT FOUND
 DCX H
 LDA UL  = DELIMITER
 CMP M
 DCX B
 JNZ SPA60  TRY AGAIN
 INX B  RESTORE THE COUNT
*
*   FOUND THE DELIMITER...TIME TO QUIT
*
SPA65 POP H
 CALL RWPS  HL = HL - BC
 MVI A,1
 STA DELFG  SET DELIM FOUND FLAG
*
*  UPDATE NBD
*
SPA69 XCHG .  BUFFER ADDRESS TO DE
 LHLD FNBD  OLD BUFFER DISPLACEMENT
 CALL ARITH  HL=HL-DE
 SHLD FNBD
*
*  UPDATE USER COUNT (UBC)
*
 LHLD UBC
 CALL ARITH  HL=HL-DE
 SHLD UBC
 ORA L  IS COUNT ZERO? A HAS H FROM ARITH
 JZ SPA80  YES, GO QUIT
*
 LDA DELFG
 DCR A
 JNZ SPA81  DELIMITER NOT FOUND
*
*  DONE, END OF COUNT OR DELIMITER FOUND
*
SPA80 CALL RBUF  RELEASE BUFFER
 JMP NRET
*
*
*  READ LAST SECTOR
*
SPA81 LHLD FBLKS
 XCHG
 LHLD TBUFA
 CALL DVBR  READ LAST BLOCK
 DB DTRLB
*
 JMP SEOF  EOF
 SHLD FBDL  SET SIZE
 SHLD FNBD  AND PTR TO END
 JMP SPABX  CONTINUE
*
*
* NOT FOUND IN THIS BUFFER
*
SPA63 POP H
 JMP SPA69  MAKE LIKE NOTHING HAPPENED
*
*
*    EOF
*
SEOF CALL RBUF
 CALL ERRL2  ERROR
 DB EER0
*
EOFER EQU SEOF
RBEOF EQU SEOF
*
 PAGE
*
*
*******************************************
*
*
*
*
*                CLOSE FILE OPERATION
*
*    UA HAS FILE NUMBER
*    THE FCB IS RELEASED
*
*    ERRORS:
*       ILLEGAL FILE NUMBER
*
*
*
CLOSE LDA UA  GET FILE NUMBER
 LXI H,SYSFIL
 CMP M
 JC NRET  OK, IT'S DONE BUT NOT SO!!!
 CALL PFCB
 CALL CLOSIT  CLOSE THE FILE
 JMP NRET  DONE
*
*********************
*
*
*       CLOSE FILE SUBROUTINE
*
*  COME HERE WITH CURRENT FCB SET
*
CLOSIT CALL CLBUF  CLOSE BUFFER
 LHLD FDLTA
 MOV A,H
 ORA L  NO CHANGE... NOT NEEDED
 JZ CLO30
 LHLD FID
 CALL SDIRX  SEARCH DIRECTORY BY ID
*
*    UPDATE FILE SIZE
*
 LHLD DBUF
 LXI D,DENBL-DEBUF  DISPLACEMENT TO SIZE
 DAD D
 XCHG
 LHLD FDLTA  GET NUMBER BLOCKS ALLOCATED
 LDAX D
 ADD L  UPDATE
 STAX D  FILE
 INX D  SIZE
 LDAX D  IN
 ADC H  BLOCKS
 STAX D
 CALL WDSK  REWRITE DIRECTORY
*
CLO30 LXI H,0
 SHLD FID  RELEASE THE FILE CONTROL BLOCK
 RET
*
*********************
*
*
*    WRITE DIRTY BLOCK AND DEALLOCATE BUFFER
*
CLBUF LHLD FBUFA
 INX H
 MOV A,H
 ORA L
 RZ .  UNBUFFERED, NOTHING TO DO
 DCX H
 SHLD TBUFA  SET TBUFA FOR UTILITIES
 CALL WDBUF  FLUSH BUFFER
 CALL DVBR  TAKE CLOSE DRIVER
 DB DTCLO  ENTRY
*
*    COME HERE TO JUST RELEASE BUFFER
*
CLBUX LHLD FBUFA
 INX H
 MOV A,H
 ORA L
 RZ .  UNBUFFERED, QUIT
 DCX H
 XCHG .  DE HAS BUFFER ADDRESS
 LHLD MINAD  HL HAS BOTTOM OF SYS GLOBAL
 CALL COMP
 RC .  DE LT HL, USER BUFFER
 LXI H,SYSTOP  NOW TOP OF SYSTEM
 CALL COMP
 RNC .  DE GT HL USER BUFFER
*
*  RELEASE BUFFER
*
 LHLD FBLKS
 XCHG .  DE HAS SIZE, HL HAS ADDRESS
 CALL DLBUF  DEALLOCATE BUFFER
 RET
*
 PAGE
*
*
*******************************************
*
*
*
*                   CLOSE MULTIPLE FILES
*
*     UA = UNIT #<0-254>  CLOSE ALL ON UNIT SPECIFIED
*        = 255            CLOSE ALL OPEN FILES
*
*     ERRORS:  NONE OTHER THAN DISK
*
*
CA MVI A,0
 STA CLCNT  COUNT UP FROM ZERO THROUGH FCB'S
 LHLD FCBASE  START AT FIRST FCB
*
*   LOOP HERE WITH NEXT FCB (PNTR ON TOS)
*
CA20 PUSH H  SAVE FCB POINTER
*
*  SEE IF FILE # < SYSFIL
*
 LXI H,SYSFIL
 LDA CLCNT
 CMP M  IS FILE# < SYSFIL?
 JC CA50  YES, SKIP
 POP H
 PUSH H  RESTORE HL
*
*  CHECK FILE ID FOR A OPEN FILE FCB (REAL? OOOBOY)
*
 LXI D,FID-FCBORG
 DAD D  MOVE TO FID BYTES
 MOV A,M
 INX H
 ORA M  CHECK IF ID=0
 JZ CA50  YES, SKIP IT
*
*  CHECK IF DESIRED UNIT
*
 LXI D,FUNIT-FID-1
 DAD D  MOVE TO UNIT NUMBER
 LDA UA
 CPI 255  CLOSE ALL
 JZ CA30  YES
 CMP M  CHECK IF THIS UNIT
 JNZ CA50  NOT THE ONE, LEAVE OPEN
*
*  CLOSE CURRENT FILE
*
CA30 POP H  GET POINTER TO FCB
 PUSH H
 CALL PFC6  SETUP FCB
 CALL CLOSIT  CLOSE THE FILE
 CALL RFCB  RESTORE FCB
*
*  MOVE TO NEXT FILE
*
CA50 LXI H,CLCNT  --> COUNTER
 INR M  COUNT UP
 LDA NFCB  = # OF FCB'S
 CMP M  HAVE WE DONE EM ALL?
 JZ NRET  YES, DONE
*
*  STILL MORE
*
 POP H
 LXI D,LNFCB
 DAD D  MOVE TO NEXT FILE
 JMP CA20  AND LOOP
*
 PAGE
*
*
*******************************************
*
*
*
*                 ENDFILE OPERATION
*
*    UA HAS FILE NUMBER
*
*    ERRORS:
*       ILLEGAL FILE NUMBER
*       PROTECTED FILE
*
*
EOF CALL PFCB  PREPARE FCB
 CALL PROTST
 DB PWRI
 JMP RER0  ERROR - PROTECTED FILE
 CALL PBUF  PREPARE BUFFER
 LHLD FNBD
 SHLD FBDL  SET BDL TO CURRENT POINTER
 XCHG
 LHLD TBUFA  DE=CT, HL=BUF
 CALL DVBR  CALL DRIVER
 DB DTEOF
*
EOF1A CALL WDB50  CLEAR THE DIRTY FLAG
 CALL RBUF  RELEASE BUFFER
 JMP NRET  RETURN
*
*********************
*
*
*  DISK FILE CLOSE (PART OF DISK INTERFACE)
*
DDEOF LHLD FID
 CALL SFCBS
 JMP RER0  OPEN MORE THAN ONCE, ERROR
 JMP EOF10  OPEN ONCE, OK
*
EOF10 LHLD FFORE
 SHLD ETMP  SAVE FORE PTR
 LHLD FNBD
 SHLD FBDL  SET BDL,ALSO
 MOV A,H
 ORI 128  SET HIGH BIT
 MOV H,A
 SHLD FFORE  SET EOF AND BYTE COUNT
 LHLD FCURSC
 SHLD ECRS  SAVE CURRENT SECTOR
 CALL WBLK  WRITE BLOCK
*
*  RELEASE ALL  BLOCKS PAST THIS ONE
*
 LHLD ETMP
 SHLD FFORE  RESTORE FORE PTR
*
EOF20 CALL DDRNB  MOVE TO NEXT BLOCK
 JMP EOF50  EOF, DONE
 CALL RFBLK  RELEASE BLOCK
 JMP EOF20  MOVE TO NEXT
*
*
EOF50 LHLD FINDX  GET INDEX FILE
 MOV A,H  IS THERE AN INDEX
 ORA L
 JZ EOF60  NO, DONE
 CALL RBUF  RELEASE BUFFER
 CALL RFCB  YES,RESTRE FCB, THEN
 JMP RNDOM  UPDATE INDEX
*
*
EOF60 LHLD FCURSC  TEST IF AT CORRECT BLOCK
 XCHG
 LHLD ECRS
 CALL COMP
 JZ EOF70  DON'T READ
 SHLD FCURSC
 CALL RBLK  RESTORE CURRENT BLOCK
 SHLD FBDL  SET BDL
*
EOF70 LHLD FBDL
 SHLD FNBD  SET NBD
 JMP EOF1A
*
*
EOFE0 EQU RER0  PROTECTED FILE
*
*