random-mirrors/MS-DOS
1
0
Fork 0
mirror of https://github.com/microsoft/MS-DOS.git synced 2024-12-01 18:15:47 +00:00
Code Issues Packages Projects Releases Wiki Activity
28fa262cc2
MS-DOS/v2.0/source/SYSINIT.ASM

1424 lines
37 KiB
NASM
Raw Normal View History

MS-DOS v2.0 Release
1983-08-13 01:53:34 +01:00
TITLE BIOS SYSTEM INITIALIZATION
FALSE EQU 0
TRUE EQU NOT FALSE
IBMVER EQU FALSE
IBM EQU IBMVER
IBMJAPVER EQU FALSE ; If TRUE set KANJI true also
MSVER EQU TRUE
ALTVECT EQU FALSE ; Switch to build ALTVECT version
HIGHMEM EQU FALSE
KANJI EQU FALSE
IF IBMVER OR IBMJAPVER
NOEXEC EQU TRUE
ELSE
NOEXEC EQU FALSE
ENDIF
; Set to agree with those in DOST:MSHEAD.ASM, ALTVECT version only
MAJOR_VERSION EQU 2
MINOR_VERSION EQU 0B ;2.11
DOSSIZE EQU 5000H
; Internal DOS data returned by DOSINIT
SYSINITVAR STRUC
DPBHEAD DD ? ; Pointer to head of DPB-FAT list
sft_addr DD ? ; Pointer to first FCB table
; The following address points to the CLOCK device
BCLOCK DD ?
; The following address is used by DISKSTATCHK it is always
; points to the console input device header
BCON DD ? ; Console device entry points
NUMIO DB 0 ; Number of disk tables
MAXSEC DW 0 ; Maximum allowed sector size
BUFFHEAD DD ? ; Head of buffer queue
DEVHEAD DD ?
SYSINITVAR ENDS
INCLUDE DOSSYM.ASM
INCLUDE DEVSYM.ASM
IF NOT IBM
IF NOT IBMJAPVER
EXTRN RE_INIT:FAR
ENDIF
ENDIF
SYSINITSEG SEGMENT PUBLIC 'SYSTEM_INIT'
ASSUME CS:SYSINITSEG,DS:NOTHING,ES:NOTHING,SS:NOTHING
EXTRN BADOPM:BYTE,CRLFM:BYTE,BADCOM:BYTE
EXTRN BADSIZ_PRE:BYTE,BADLD_PRE:BYTE
EXTRN BADSIZ_POST:BYTE,BADLD_POST:BYTE
EXTRN SYSSIZE:BYTE,BADCOUNTRY:BYTE
PUBLIC CURRENT_DOS_LOCATION
PUBLIC FINAL_DOS_LOCATION
PUBLIC DEVICE_LIST
PUBLIC MEMORY_SIZE
PUBLIC DEFAULT_DRIVE
PUBLIC BUFFERS
PUBLIC FILES
PUBLIC SYSINIT
IF HIGHMEM
PUBLIC DPBBUF_SIZ
ENDIF
SYSINIT:
JMP GOINIT
DOSINFO LABEL DWORD
DW 0000
CURRENT_DOS_LOCATION DW 0000
MSDOS LABEL DWORD
ENTRY_POINT LABEL DWORD
DW 0000
FINAL_DOS_LOCATION DW 0000
DEVICE_LIST DD 00000000
IF HIGHMEM
DPBBUF_SIZ DW (4472 + 15) / 16
ENDIF
MEMORY_SIZE DW 0001
DEFAULT_DRIVE DB 00
BUFFERS DB 2
FILES DB 8
COMMAND_LINE DB 2,0,"P" ; Default Command.com Args
DB 29 DUP (0)
ZERO DB 0
IF NOT NOEXEC
COMEXE EXEC0 <0,COMMAND_LINE,DEFAULT_DRIVE,ZERO>
ENDIF
COUNT DW 0000
CHRPTR DW 0000
BUFPTR LABEL DWORD ; LEAVE THIS STUFF IN ORDER!
MEMLO DW 0
PRMBLK LABEL WORD
MEMHI DW 0
LDOFF DW 0
AREA DW 0
PACKET DB 22
DB 0
DB 0 ; INITIALIZE CODE
DW 0
DB 8 DUP (?)
UNITCOUNT DB 0
BREAK_ADDR DD 0
BPB_ADDR DD 0
GOINIT:
CLD
XOR SI,SI
MOV DI,SI
IF MSVER
MOV CX,[MEMORY_SIZE]
CMP CX,1
JNZ NOSCAN
MOV CX,2048 ; START SCANNING AT 32K BOUNDARY
XOR BX,BX
MEMSCAN:INC CX
JZ SETEND
MOV DS,CX
MOV AL,[BX]
NOT AL
MOV [BX],AL
CMP AL,[BX]
NOT AL
MOV [BX],AL
JZ MEMSCAN
SETEND:
MOV [MEMORY_SIZE],CX
ENDIF
IF IBMVER OR IBMJAPVER
MOV CX,[MEMORY_SIZE]
ENDIF
NOSCAN:
MOV AX,CS
MOV DS,AX
ASSUME DS:SYSINITSEG
IF HIGHMEM
SUB CX,(DOSSIZE / 16) ; Leave room for DOS
SUB CX,CS:[DPBBUF_SIZ] ; Allow OEM to tune
ENDIF
MOV AX,OFFSET SYSSIZE + 15
SHR AX,1 ; Divide by 16 for paras
SHR AX,1
SHR AX,1
SHR AX,1
SUB CX,AX
MOV ES,CX
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW ; RELOCATE SYSINIT
ASSUME ES:SYSINITSEG
PUSH ES
MOV AX,OFFSET SYSIN
PUSH AX
AAA PROC FAR
RET
AAA ENDP
;
; MOVE THE DOS TO ITS PROPER LOCATION
;
SYSIN:
ASSUME DS:NOTHING,ES:SYSINITSEG,SS:NOTHING
MOV AX,[CURRENT_DOS_LOCATION]
MOV DS,AX
MOV AX,[FINAL_DOS_LOCATION]
MOV ES,AX
ASSUME ES:NOTHING
XOR SI,SI
MOV DI,SI
MOV CX,DOSSIZE/2
REP MOVSW
LDS SI,[DEVICE_LIST]
MOV DX,[MEMORY_SIZE]
CLI
MOV AX,CS
MOV SS,AX
MOV SP,OFFSET LOCSTACK
ASSUME SS:SYSINITSEG
IF NOT ALTVECT
STI ; Leave INTs disabled for ALTVECT
ENDIF
LOCSTACK LABEL BYTE
CALL MSDOS
MOV WORD PTR [DOSINFO+2],ES ; SAVE POINTER TO DOS INFO
MOV WORD PTR [DOSINFO],DI
IF NOT IBM
IF NOT IBMJAPVER
CALL RE_INIT ; Re-call the BIOS
ENDIF
ENDIF
STI
CLD
IF HIGHMEM
PUSH DS
MOV BX,DS
ADD BX,10H
MOV ES,BX
PUSH CS
POP DS
XOR SI,SI
MOV DI,SI
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW
POP DS
PUSH ES
MOV AX,OFFSET SECONDRELOC
PUSH AX
BBB PROC FAR
RET
BBB ENDP
SECONDRELOC:
MOV AX,CS
CLI
MOV SS,AX
MOV SP,OFFSET LOCSTACK
STI
ELSE
MOV BX,CS
SUB BX,10H
MOV ES,BX
XOR SI,SI
MOV DI,SI
MOV CX,80H
REP MOVSW
MOV AH,SET_CURRENT_PDB
INT 21H
ENDIF
PUSH DS
PUSH CS
POP DS
MOV DX,OFFSET INT24 ; SET UP INT 24 HANDLER
MOV AX,(SET_INTERRUPT_VECTOR SHL 8) OR 24H
INT 21H
IF ALTVECT
MOV DX,OFFSET BOOTMES
CALL PRINT ; Print message DOSINIT couldn't
ENDIF
POP DS
MOV DL,[DEFAULT_DRIVE]
OR DL,DL
JZ NODRVSET
DEC DL ; A = 0
MOV AH,SET_DEFAULT_DRIVE
INT 21H ; SELECT THE DISK
NODRVSET:
CALL DOCONF ; DO THE CONFIG STUFF
IF HIGHMEM
PUSH DS
MOV AX,OFFSET SYSSIZE + 15
MOV CL,4
SHR AX,CL ; Divide by 16 to get para
MOV CX,ES
SUB CX,AX
MOV ES,CX
PUSH CS
POP DS
XOR SI,SI
MOV DI,SI
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW
POP DS
PUSH ES
MOV AX,OFFSET THIRDRELOC
PUSH AX
CCC PROC FAR
RET
CCC ENDP
THIRDRELOC:
MOV AX,CS
CLI
MOV SS,AX
MOV SP,OFFSET LOCSTACK
STI
ENDIF
IF NOEXEC
MOV BP,DS ; SAVE COMMAND.COM SEGMENT
PUSH DS
POP ES
MOV BX,CS
SUB BX,10H
MOV DS,BX
XOR SI,SI
MOV DI,SI
MOV CX,80H
REP MOVSW
MOV BX,ES
MOV AH,SET_CURRENT_PDB
INT 21H
MOV ES:[PDB_PARENT_PID],ES ; WE ARE THE ROOT
ENDIF
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
MOV AL,[FILES]
CBW
MOV CX,AX
XOR BX,BX ; Close standard input
MOV AH,CLOSE
INT 21H
MOV BX,2
RCCLLOOP: ; Close everybody but standard output
MOV AH,CLOSE
INT 21H
INC BX
LOOP RCCLLOOP
MOV DX,OFFSET CONDEV
MOV AL,2
MOV AH,OPEN ; OPEN CON FOR READ/WRITE
STC
INT 21H
JNC GOAUX
CALL BADFIL
JMP SHORT GOAUX2
GOAUX: PUSH AX
MOV BX,1 ; close standard output
MOV AH,CLOSE
INT 21H
POP AX
MOV BX,AX ; New device handle
MOV AH,XDUP
INT 21H ; Dup to 1, STDOUT
MOV AH,XDUP
INT 21H ; Dup to 2, STDERR
GOAUX2: MOV DX,OFFSET AUXDEV
MOV AL,2 ; READ/WRITE ACCESS
CALL OPEN_DEV
MOV DX,OFFSET PRNDEV
MOV AL,1 ; WRITE ONLY
CALL OPEN_DEV
;
; SET UP THE PARAMETERS FOR COMMAND
;
GOSET:
MOV SI,OFFSET COMMAND_LINE+1
IF NOEXEC
MOV DI,81H
ELSE
PUSH DS
POP ES
MOV DI,SI
ENDIF
MOV CL,-1
COMTRANLP: ; FIND LENGTH OF COMMAND LINE
INC CL
LODSB
STOSB ; COPY COMMAND LINE IN
OR AL,AL
JNZ COMTRANLP
DEC DI
MOV AL,0DH
STOSB
IF NOEXEC
MOV ES:[80H],CL
MOV AL,[DEFAULT_DRIVE]
MOV ES:[5CH],AL
ELSE
MOV [COMMAND_LINE],CL ; Count
ENDIF
PUSH CS
POP ES
ASSUME ES:SYSINITSEG
MOV DX,OFFSET COMMND ; NOW POINTING TO FILE DESCRIPTION
IF NOEXEC
MOV ES,BP ; SET LOAD ADDRESS
MOV BX,100H
CALL LDFIL ; READ IN COMMAND
JC COMERR
MOV DS,BP
CLI
MOV DX,80H
MOV SS,BP
MOV SP,DX
STI
XOR AX,AX ; PUSH A WORD OF ZEROS
PUSH AX
MOV AH,SET_DMA ; SET DISK TRANFER ADDRESS
INT 21H
PUSH BP ; SET HIGH PART OF JUMP ADDRESS
MOV AX,100H
PUSH AX ; SET LOW PART OF JUMP ADDRESS
CCC PROC FAR
RET ; CRANK UP COMMAND!
CCC ENDP
ELSE
MOV BX,OFFSET COMEXE
MOV WORD PTR [BX.EXEC0_COM_LINE+2],CS
MOV WORD PTR [BX.EXEC0_5C_FCB+2],CS
MOV WORD PTR [BX.EXEC0_6C_FCB+2],CS
XOR AX,AX
MOV AH,EXEC
STC ; IN CASE OF INT 24
INT 21H ; GO START UP COMMAND
ENDIF
COMERR:
MOV DX,OFFSET BADCOM ; WANT TO PRINT COMMAND ERROR
CALL BADFIL
STALL: JMP STALL
DOCONF:
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
MOV BX,0FFFFH
MOV AH,ALLOC
INT 21H ; FIRST TIME FAILS
MOV AH,ALLOC
INT 21H ; SECOND TIME GETS IT
MOV [AREA],AX
IF HIGHMEM
ADD AX,BX
ENDIF
MOV [MEMHI],AX
MOV AX,(CHAR_OPER SHL 8) ; GET SWITCH CHARACTER
INT 21H
MOV [COMMAND_LINE+1],DL
MOV DX,OFFSET CONFIG ; NOW POINTING TO FILE DESCRIPTION
MOV AX,OPEN SHL 8 ; OPEN FILE "CONFIG.SYS"
STC ; IN CASE OF INT 24
INT 21H ; FUNCTION REQUEST
JC ENDFILE
JMP NOPROB ; PROBLEM WITH OPEN
ENDFILE:
PUSH CS
POP DS
CALL ROUND
MOV AL,[FILES]
SUB AL,5
JBE DOBUFF
CBW
IF HIGHMEM
PUSH AX
MOV BL,SIZE SF_ENTRY
MUL BL
ADD AX,15+6
MOV CL,4
SHR AX,CL
SUB [MEMHI],AX
POP AX
ENDIF
MOV BX,[MEMLO]
MOV DX,[MEMHI]
LDS DI,[DOSINFO] ; GET POINTER TO DOS DATA
LDS DI,[DI+SFT_ADDR] ; DS:BP POINTS TO SFT
MOV WORD PTR [DI+SFT_LINK],BX
MOV WORD PTR [DI+SFT_LINK+2],DX ; SET POINTER TO NEW SFT
PUSH CS
POP DS
LES DI,DWORD PTR [MEMLO] ; POINT TO NEW SFT
MOV WORD PTR ES:[DI+SFT_LINK],-1
MOV ES:[DI+SFT_COUNT],AX
MOV BL,SIZE SF_ENTRY
MUL BL ; AX = NUMBER OF BYTES TO CLEAR
MOV CX,AX
IF HIGHMEM
MOV AX,6
ELSE
ADD [MEMLO],AX ; ALLOCATE MEMORY
MOV AX,6
ADD [MEMLO],AX ; REMEMBER THE HEADER TOO
ENDIF
ADD DI,AX
XOR AX,AX
REP STOSB ; CLEAN OUT THE STUFF
DOBUFF: CALL ROUND
DEC [BUFFERS]
JZ BUF1
PUSH DS
LES DI,BUFPTR
LDS BX,DOSINFO
IF HIGHMEM
MOV AX,[BX.MAXSEC]
ADD AX,BUFINSIZ + 15
MOV CL,4
SHR AX,CL
SUB CS:[MEMHI],AX
MOV ES,CS:[MEMHI]
ENDIF
MOV AX,WORD PTR [BX.BUFFHEAD]
MOV WORD PTR ES:[DI.NEXTBUF],AX
MOV AX,WORD PTR [BX.BUFFHEAD+2]
MOV WORD PTR ES:[DI.NEXTBUF+2],AX
MOV WORD PTR [BX.BUFFHEAD],DI
MOV WORD PTR [BX.BUFFHEAD+2],ES
MOV WORD PTR ES:[DI.BUFDRV],00FFH ; NEW BUFFER FREE
MOV BX,[BX.MAXSEC]
POP DS
IF NOT HIGHMEM
ADD BX,BUFINSIZ
ADD [MEMLO],BX
ENDIF
JMP DOBUFF
BUF1: CALL ROUND
MOV BX,[MEMHI]
MOV AX,[AREA]
MOV ES,AX ; CALC WHAT WE NEEDED
SUB BX,AX
IF HIGHMEM
DEC BX ; Arena
PUSH BX
ENDIF
MOV AH,SETBLOCK
INT 21H ; GIVE THE REST BACK
IF NOT HIGHMEM
PUSH ES
MOV AX,ES
DEC AX
MOV ES,AX
MOV ES:[arena_owner],8 ; Set impossible owner
POP ES
ENDIF
IF HIGHMEM
MOV BX,0FFFFH
MOV AH,ALLOC
INT 21H
MOV AH,ALLOC
INT 21H
PUSH ES
DEC AX
MOV ES,AX
MOV ES:[arena_owner],8 ; Set impossible owner
POP ES
IF NOT NOEXEC
MOV ES,[AREA]
MOV AH,DEALLOC
INT 21H
ENDIF
POP BX
MOV AX,[AREA]
MOV DS,AX
ADD AX,BX
MOV ES,AX
ELSE
IF NOEXEC
MOV BX,0FFFFH ; ALLOCATE THE REST OF MEM FOR COMMAND
MOV AH,ALLOC
INT 21H
MOV AH,ALLOC
INT 21H
MOV DS,AX
ENDIF
ENDIF
RET
BADOP: MOV DX,OFFSET BADOPM ; WANT TO PRINT COMMAND ERROR
CALL PRINT
JMP COFF
NOPROB: ; GET FILE SIZE (NOTE < 64K!!)
MOV BX,AX
XOR CX,CX
XOR DX,DX
MOV AX,(LSEEK SHL 8) OR 2
INT 21H
MOV [COUNT],AX
XOR DX,DX
MOV AX,LSEEK SHL 8 ; Reset pointer to beginning of file
INT 21H
MOV DX,CS
IF HIGHMEM
MOV AX,OFFSET SYSSIZE + 15
MOV CL,4
SHR AX,CL
ADD DX,AX
ELSE
MOV AX,[COUNT]
ADD AX,15
MOV CL,4
SHR AX,CL ; NUMBER OF SEGMENTS
SUB DX,AX
SUB DX,11H ; ROOM FOR HEADER
ENDIF
MOV DS,DX
MOV ES,DX
ASSUME DS:NOTHING,ES:NOTHING
XOR DX,DX
MOV CX,[COUNT]
MOV AH,READ
STC ; IN CASE OF INT 24
INT 21H ; Function request
PUSHF
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
PUSH AX
MOV AH,CLOSE
INT 21H
POP AX
POPF
JC CONFERR ; IF NOT WE'VE GOT A PROBLEM
CMP CX,AX
JZ GETCOM ; COULDN'T READ THE FILE
CONFERR:
MOV DX,OFFSET CONFIG ; WANT TO PRINT CONFIG ERROR
CALL BADFIL
ENDFILV:JMP ENDFILE
GETCOM:
CALL ORGANIZE ; ORGANIZE THE FILE
CALL GETCHR
CONFLP: JC ENDFILV
MOV AH,AL
CALL GETCHR
CMP AH,'B' ; BUFFER COMMAND?
JNZ TRYC
CALL GETNUM
JZ COFF
CMP AX,100
JAE badop
MOV [BUFFERS],AL
JMP SHORT COFF
TRYC: CMP AH,'C'
JZ GOTC
JMP TRYD
GOTC:
CMP AL,'O' ; FIRST LETTER OF "ON"
JNZ COFF
CALL GETCHR
JC ENDFILV
CMP AL,'N' ; SECOND LETTER OF "ON"
JNZ COFF
MOV AH,SET_CTRL_C_TRAPPING ; TURN ON CONTROL-C CHECK
MOV AL,1
MOV DL,AL
INT 21H
COFF: PUSH CS
POP DS
CALL NEWLINE
JMP CONFLP
TRYD: CMP AH,'D'
JZ GOTD
JMP TRYF
GOTD: MOV BX,CS
MOV DS,BX
MOV WORD PTR [BPB_ADDR],SI
MOV WORD PTR [BPB_ADDR+2],ES
CALL ROUND
IF HIGHMEM
PUSH DS
PUSH ES
POP DS
MOV DX,SI
MOV AX,OPEN SHL 8
STC ; In case INT 24H
INT 21H
POP DS
JC BADBRK
MOV BX,AX
XOR DX,DX
MOV CX,DX
MOV AX,(LSEEK SHL 8) OR 2
INT 21H
PUSH AX
MOV AH,CLOSE
INT 21H
POP AX ; DX:AX is size of file
ADD AX,15
ADC DX,0
MOV CL,4
SHR AX,CL
MOV CL,12
SHL DX,CL
OR AX,DX ; AX is size in PARA
MOV CX,[MEMHI]
SUB [MEMHI],AX
JNC SIZEOK
MOV [MEMHI],CX ; Not enough memory
JMP SHORT BADBRK
SIZEOK:
MOV BX,CS
ENDIF
XOR AX,AX
MOV WORD PTR [ENTRY_POINT],AX
MOV AX,[MEMHI]
MOV WORD PTR [ENTRY_POINT+2],AX ; SET ENTRY POINT
IF NOT NOEXEC
MOV [LDOFF],AX ; SET LOAD OFFSET
ENDIF
PUSH ES
POP DS
MOV DX,SI ; DS:DX POINTS TO FILE NAME
IF NOEXEC
LES BX,DWORD PTR CS:[MEMLO]
CALL LDFIL ; LOAD IN THE DEVICE DRIVER
ELSE
MOV ES,BX
MOV BX,OFFSET PRMBLK ; ES:BX POINTS TO PARAMETERS
MOV AL,3
MOV AH,EXEC
STC ; IN CASE OF INT 24
INT 21H ; LOAD IN THE DEVICE DRIVER
ENDIF
PUSH DS
POP ES ; ES:SI BACK TO CONFIG.SYS
PUSH CS
POP DS ; DS BACK TO SYSINIT
JNC GOODLD
BADBRK: CALL BADLOAD
JMP COFF
GOODLD: PUSH ES ; INITIALIZE THE DEVICE
PUSH SI
PUSH CS
POP ES
MOV BX,SDEVSTRAT
CALL CALLDEV
MOV BX,SDEVINT
CALL CALLDEV
PUSH CS
POP DS
IF NOT HIGHMEM
MOV AX,WORD PTR [BREAK_ADDR+2] ; REMOVE THE INIT CODE
CMP AX,[MEMORY_SIZE]
JB BREAKOK
POP SI
POP ES
JMP BADBRK
BREAKOK:
MOV [MEMHI],AX
MOV AX,WORD PTR [BREAK_ADDR]; REMOVE THE INIT CODE
MOV [MEMLO],AX
ENDIF
LDS DX,[ENTRY_POINT] ; SET DS:DX TO HEADER
MOV SI,DX
ADD SI,SDEVATT ; DS:SI POINTS TO ATTRIBUTES
LES DI,CS:[DOSINFO] ; ES:DI POINT TO DOS INFO
MOV AX,DS:[SI] ; GET ATTRIBUTES
TEST AX,DEVTYP ; TEST IF BLOCK DEV
JZ ISBLOCK
TEST AX,ISCIN ; IS IT A CONSOLE IN?
JZ TRYCLK
MOV WORD PTR ES:[DI.BCON],DX
MOV WORD PTR ES:[DI.BCON+2],DS
TRYCLK: TEST AX,ISCLOCK ; IS IT A CLOCK DEVICE?
JZ GOLINK
MOV WORD PTR ES:[DI+BCLOCK],DX
MOV WORD PTR ES:[DI+BCLOCK+2],DS
GOLINK: JMP LINKIT
ISBLOCK:
MOV AL,CS:[UNITCOUNT] ; IF NO UNITS FOUND....
OR AL,AL
JNZ PERDRV
IF NOT HIGHMEM
MOV CS:[MEMLO],0 ; ...ERASE THE DEVICE
ENDIF
MOV AX,-1
JMP ENDDEV
PERDRV:
CBW
MOV CX,AX
MOV DH,AH
MOV DL,ES:[DI.NUMIO] ; GET NUMBER OF DEVICES
ADD ES:[DI.NUMIO],AL ; UPDATE THE AMOUNT
LDS BX,CS:[BPB_ADDR] ; POINT TO BPB ARRAY
PERUNIT:
LES BP,CS:[DOSINFO]
LES BP,DWORD PTR ES:[BP.DPBHEAD]; GET FIRST DPB
SCANDPB:CMP WORD PTR ES:[BP.DPB_NEXT_DPB],-1
JZ FOUNDPB
LES BP,ES:[BP.DPB_NEXT_DPB]
JMP SCANDPB
FOUNDPB:
MOV AX,CS:[MEMLO]
MOV WORD PTR ES:[BP.DPB_NEXT_DPB],AX
IF HIGHMEM
MOV AX,(DPBSIZ + 15) / 16
SUB CS:[MEMHI],AX
ENDIF
MOV AX,CS:[MEMHI]
MOV WORD PTR ES:[BP.DPB_NEXT_DPB+2],AX
LES BP,DWORD PTR CS:[MEMLO]
IF NOT HIGHMEM
ADD WORD PTR CS:[MEMLO],DPBSIZ
ENDIF
MOV WORD PTR ES:[BP.DPB_NEXT_DPB],-1
MOV ES:[BP.DPB_FIRST_ACCESS],-1
MOV SI,[BX] ; DS:SI POINTS TO BPB
INC BX
INC BX ; POINT TO NEXT GUY
MOV WORD PTR ES:[BP.DPB_DRIVE],DX
MOV AH,SETDPB ; HIDDEN SYSTEM CALL
INT 21H
MOV AX,ES:[BP.DPB_SECTOR_SIZE]
PUSH ES
LES DI,CS:[DOSINFO] ; ES:DI POINT TO DOS INFO
CMP AX,ES:[DI.MAXSEC]
POP ES
JBE NOTMAX
POP SI
POP ES
MOV DX,OFFSET BADSIZ_PRE
MOV BX,OFFSET BADSIZ_POST
CALL PRNERR
JMP COFF
NOTMAX: PUSH DS
PUSH DX
LDS DX,CS:[ENTRY_POINT]
MOV WORD PTR ES:[BP.DPB_DRIVER_ADDR],DX
MOV WORD PTR ES:[BP.DPB_DRIVER_ADDR+2],DS
POP DX
POP DS
INC DX
INC DH
LOOP PERUNIT
LINKIT:
LES DI,CS:[DOSINFO] ; ES:DI = DOS TABLE
MOV CX,WORD PTR ES:[DI.DEVHEAD] ; DX:CX = HEAD OF LIST
MOV DX,WORD PTR ES:[DI.DEVHEAD+2]
LDS SI,CS:[ENTRY_POINT] ; DS:SI = DEVICE LOCATION
MOV WORD PTR ES:[DI.DEVHEAD],SI ; SET HEAD OF LIST IN DOS
MOV WORD PTR ES:[DI.DEVHEAD+2],DS
MOV AX,DS:[SI] ; GET POINTER TO NEXT DEVICE
MOV WORD PTR CS:[ENTRY_POINT],AX; AND SAVE IT
MOV WORD PTR DS:[SI],CX ; LINK IN THE DRIVER
MOV WORD PTR DS:[SI+2],DX
ENDDEV:
POP SI
POP ES
INC AX ; AX = FFFF?
JZ COFFV
JMP GOODLD ; OTHERWISE PRETEND WE LOADED IT IN
COFFV: JMP COFF
TRYQ:
CMP AH,'Q'
JNZ TRYW
CALL GETNUM
JZ COFFV
OR AH,AH
JNZ COFFV
MOV AH,INTERNATIONAL ; AL is country code
MOV DX,-1 ; Set country
INT 21H
JNC COFFV
MOV DX,OFFSET BADCOUNTRY
CALL PRINT
JMP COFFV
TRYF:
CMP AH,'F'
JNZ TRYQ
CALL GETNUM
JZ COFFV
CMP AX,100
JAE TryX
MOV [FILES],AL
JMP COFFV
TRYW:
CMP AH,'W'
JNZ TRYA
MOV DL,AL
MOV AX,(CHAR_OPER SHL 8) OR 1 ; SET SWITCH CHARACTER
MOV [COMMAND_LINE+1],DL
INT 21H
JMP COFF
TRYA:
CMP AH,'A'
JNZ TRYS
CMP AL,'F' ; FIRST LETTER OF "FALSE"
JNZ COFFJ
MOV AX,(CHAR_OPER SHL 8) OR 3 ; TURN ON "/DEV" PREFIX
XOR DL,DL
INT 21H
COFFJ: JMP COFF
TRYS:
CMP AH,'S'
JNZ TRYX
MOV [COMMAND_LINE+1],0
MOV DI,OFFSET COMMND + 1
MOV [DI-1],AL
STORESHELL:
CALL GETCHR
OR AL,AL
JZ GETSHPARMS
CMP AL," "
JB ENDSH
MOV [DI],AL
INC DI
JMP STORESHELL
ENDSH:
MOV BYTE PTR [DI],0
CALL GETCHR
CMP AL,10
JNZ CONV
CALL GETCHR
CONV: JMP CONFLP
TRYX:
JMP BADOP
GETSHPARMS:
MOV BYTE PTR [DI],0
MOV DI,OFFSET COMMAND_LINE+1
PARMLOOP:
CALL GETCHR
CMP AL," "
JB ENDSH
MOV [DI],AL
INC DI
JMP PARMLOOP
GETCHR: MOV CX,COUNT
JCXZ NOCHAR
MOV SI,CHRPTR
MOV AL,ES:[SI]
DEC COUNT
INC CHRPTR
CLC
RET
NOCHAR: STC
RET
ORGANIZE:
MOV CX,[COUNT]
JCXZ NOCHAR
CALL MAPCASE
XOR SI,SI
MOV DI,SI
ORG1: CALL GET ; SKIP LEADING CONTROL CHARACTERS
CMP AL,' '
JB ORG1
PUSH CX
PUSH SI
PUSH DI
MOV BP,SI
DEC BP
MOV SI,OFFSET COMTAB ; Prepare to search command table
MOV CH,0
FINDCOM:
MOV DI,BP
MOV CL,[SI]
INC SI
JCXZ NOCOM
REPE CMPSB
LAHF
ADD SI,CX ; Bump to next position without affecting flags
SAHF
LODSB ; Get indicator letter
JNZ FINDCOM
POP DI
POP SI
POP CX
JMP SHORT GOTCOM
NOCOM:
POP DI
POP SI
POP CX
MOV AL,'Z'
GOTCOM: STOSB ; SAVE INDICATOR CHAR IN BUFFER
ORG2: CALL GET2 ; SKIP NAME UNTIL DELIMETER
CALL DELIM ;
JNZ ORG2
CALL GET ; GET CHARS TO RIGHT OF EQUALS SIGN
STOSB
ORG4: CALL GET2
STOSB
CMP AL,' '
JA ORG4
CMP AL,10
JZ ORG1
MOV BYTE PTR ES:[DI-1],0
ORG5: CALL GET2
STOSB
CMP AL,10
JNZ ORG5
JMP ORG1
GET2:
JCXZ NOGET
MOV AL,ES:[SI]
INC SI
DEC CX
RET
GET: JCXZ NOGET
MOV AL,ES:[SI]
INC SI
DEC CX
CALL DELIM
JZ GET
GRET: RET
DELIM: CMP AL,' '
JZ GRET
CMP AL,9
JZ GRET
CMP AL,'='
JZ GRET
CMP AL,','
JZ GRET
CMP AL,';'
RET
NOGET: POP CX
MOV COUNT,DI
XOR SI,SI
MOV CHRPTR,SI
RET
;
; NEWLINE RETURNS WITH FIRST CHARACTER OF NEXT LINE
;
NEWLINE:CALL GETCHR ; SKIP NON-CONTROL CHARACTERS
JC NONEW
CMP AL,10 ; LOOK FOR LINE FEED
JNZ NEWLINE
CALL GETCHR
NONEW: RET
MAPCASE:
PUSH CX
PUSH SI
PUSH DS
PUSH ES
POP DS
XOR SI,SI
CONVLOOP:
LODSB
IF KANJI
CALL TESTKANJ
JZ NORMCONV
INC SI ; Skip next char
DEC CX
JCXZ CONVDONE ; Just ignore 1/2 kanji error
; Fall through, know AL is not in 'a'-'z' range
NORMCONV:
ENDIF
CMP AL,'a'
JB NOCONV
CMP AL,'z'
JA NOCONV
SUB AL,20H
MOV [SI-1],AL
NOCONV:
LOOP CONVLOOP
CONVDONE:
POP DS
POP SI
POP CX
RET
IF KANJI
TESTKANJ:
CMP AL,81H
JB NOTLEAD
CMP AL,9FH
JBE ISLEAD
CMP AL,0E0H
JB NOTLEAD
CMP AL,0FCH
JBE ISLEAD
NOTLEAD:
PUSH AX
XOR AX,AX ; Set zero
POP AX
RET
ISLEAD:
PUSH AX
XOR AX,AX ; Set zero
INC AX ; Reset zero
POP AX
RET
ENDIF
ASSUME DS:NOTHING
ROUND: MOV AX,[MEMLO]
IF NOT HIGHMEM
ADD AX,15
ENDIF
SHR AX,1
SHR AX,1
SHR AX,1
SHR AX,1
ADD [MEMHI],AX
XOR AX,AX
MOV [MEMLO],AX
RET
CALLDEV:MOV DS,WORD PTR CS:[ENTRY_POINT+2]
ADD BX,WORD PTR CS:[ENTRY_POINT]; Do a little relocation
MOV AX,DS:[BX]
PUSH WORD PTR CS:[ENTRY_POINT]
MOV WORD PTR CS:[ENTRY_POINT],AX
MOV BX,OFFSET PACKET
CALL [ENTRY_POINT]
POP WORD PTR CS:[ENTRY_POINT]
RET
BADNUM: POP AX ; POP RETURN ADDRESS
JMP BADOP
ToDigit:
SUB AL,'0'
JB NotDig
CMP AL,9
JA NotDig
CLC
RET
NotDig: STC
RET
GETNUM: XOR BX,BX ; running count is zero
B2: CALL ToDigit ; do we have a digit
JC BadNum ; no, bomb
XCHG AX,BX ; put total in AX
PUSH BX ; save digit
MOV BX,10 ; base of arithmetic
MUL BX ; shift by one decimal digit
POP BX ; get back digit
ADD AL,BL ; get total
ADC AH,0 ; make that 16 bits
JC BADNUM ; too big a number
XCHG AX,BX ; stash total
CALL GETCHR ; GET NEXT DIGIT
JC B1 ; no more characters
OR AL,AL ; end of line separator?
JNZ B2 ; no, try as a valid character
INC COUNT ; one more character to scan
DEC CHRPTR ; back up over separator
B1: MOV AX,BX ; get proper count
OR AX,AX
RET
;
; ES:SI POINTS TO FILE NAME (NUL TERMINATED)
; DS:DX POINTS TO STRING TO OUTPUT IN FRONT OF NAME ($ TERM)
;
BADFIL:
PUSH CS
POP ES
MOV SI,DX
BADLOAD:
MOV DX,OFFSET BADLD_PRE ; WANT TO PRINT CONFIG ERROR
MOV BX,OFFSET BADLD_POST
PRNERR:
PUSH CS
POP DS
MOV AH,STD_CON_STRING_OUTPUT
INT 21H
PRN1: MOV DL,ES:[SI]
OR DL,DL
JZ PRN2
MOV AH,STD_CON_OUTPUT
INT 21H
INC SI
JMP PRN1
PRN2: MOV DX,BX
PRINT: MOV AH,STD_CON_STRING_OUTPUT
INT 21H
RET
;
; LOAD FILE CALLED [DS:DX] AT MEMORY LOCATION ES:BX
;
LDFIL:
PUSH AX
PUSH BX
PUSH CX
PUSH DX
PUSH SI
PUSH DS
PUSH BX
XOR AX,AX ; OPEN THE FILE
MOV AH,OPEN
STC ; IN CASE OF INT 24
INT 21H
POP DX ; Trans addr is DS:DX
JC LDRET
PUSH ES ; READ THE FILE IN
POP DS
MOV BX,AX ; Handle in BX
MOV CX,0FF00H
MOV AH,READ
STC ; IN CASE OF INT 24
INT 21H
JC LDRET
MOV SI,DX ; CHECK FOR EXE FILE
CMP WORD PTR [SI],"ZM"
JNZ LDCLS
LDERR: STC
JMP SHORT LDRET
LDCLS: MOV AH,CLOSE ; CLOSE THE FILE
STC
INT 21H
LDRET: POP DS
POP SI
POP DX
POP CX
POP BX
POP AX
RET
;
; OPEN DEVICE POINTED TO BY DX, AL HAS ACCESS CODE
; IF UNABLE TO OPEN DO A DEVICE OPEN NULL DEVICE INSTEAD
;
OPEN_DEV:
CALL OPEN_FILE
JNC OPEN_DEV3
OPEN_DEV1:
MOV DX,OFFSET NULDEV
CALL OPEN_FILE
OPEN_DEV2:
RET
OPEN_DEV3:
XOR AX,AX ; GET DEVICE INFO
MOV AH,IOCTL
INT 21H
TEST DL,10000000B
JNZ OPEN_DEV2
MOV AH,CLOSE
INT 21H
JMP OPEN_DEV1
OPEN_FILE:
MOV AH,OPEN
STC
INT 21H
RET
INT24: ADD SP,6 ; RESTORE MACHINE STATE
POP AX
POP BX
POP CX
POP DX
POP SI
POP DI
POP BP
POP DS
POP ES
PUSH AX
MOV AH,GET_DEFAULT_DRIVE ; INITIALIZE DOS
INT 21H
POP AX
IRET ; BACK TO USER
IF ALTVECT
BOOTMES DB 13
TEN: DB 10
DB "MS-DOS version "
DB MAJOR_VERSION + "0"
DB "."
DB (MINOR_VERSION / 10) + "0"
DB (MINOR_VERSION MOD 10) + "0"
DB 13,10
DB "Copyright 1981,82 Microsoft Corp.",13,10,"$"
ENDIF
NULDEV DB "\DEV\NUL",0
CONDEV DB "\DEV\CON",0
AUXDEV DB "\DEV\AUX",0
PRNDEV DB "\DEV\PRN",0
CONFIG DB "\CONFIG.SYS",0
COMMND DB "\COMMAND.COM",0
COMTAB LABEL BYTE
DB 7,"BUFFERS",'B'
DB 5,"BREAK",'C'
DB 5,"SHELL",'S'
DB 6,"DEVICE",'D'
DB 5,"FILES",'F'
DB 8,"SWITCHAR",'W'
DB 8,"AVAILDEV",'A'
DB 7,"COUNTRY",'Q'
DB 0
SYSINITSEG ENDS
END

Reference in New Issue Copy Permalink