mirror of
https://github.com/microsoft/MS-DOS.git
synced 2024-12-01 18:15:47 +00:00
749 lines
20 KiB
NASM
749 lines
20 KiB
NASM
;
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; system call entry points MSDOS
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;
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INCLUDE DOSSEG.ASM
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CODE SEGMENT BYTE PUBLIC 'CODE'
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ASSUME SS:DOSGROUP,CS:DOSGROUP
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.xlist
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.xcref
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INCLUDE DOSSYM.ASM
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INCLUDE DEVSYM.ASM
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.cref
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.list
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i_need YEAR,WORD
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i_need DAY,BYTE
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i_need WeekDay,BYTE
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i_need TimeBuf,6
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i_need BCLOCK,DWORD
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i_need DskErr,BYTE
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i_need Attrib,BYTE
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i_need Name1,BYTE
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i_need Name2,BYTE
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i_need Name3,BYTE
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i_need DelAll,BYTE
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i_need ThisDPB,DWORD
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i_need CurBuf,DWORD
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i_need LastEnt,WORD
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i_need ThisDrv,BYTE
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i_need DirStart,WORD
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i_need DevPt,DWORD
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i_need Creating,BYTE
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i_need VolID,BYTE
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i_need FoundDel,BYTE
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SUBTTL DATE AND TIME - SYSTEM CALLS 42,43,44,45; S/G DATE,TIME
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PAGE
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procedure $GET_DATE,NEAR ;System call 42
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; None
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; Function:
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; Return current date
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; Returns:
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; Date in CX:DX
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PUSH SS
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POP DS
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ASSUME DS:DOSGROUP
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invoke READTIME ;Check for rollover to next day
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MOV AX,[YEAR]
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MOV BX,WORD PTR [DAY]
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invoke get_user_stack ;Get pointer to user registers
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ASSUME DS:NOTHING
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MOV [SI.user_DX],BX ;DH=month, DL=day
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ADD AX,1980 ;Put bias back
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MOV [SI.user_CX],AX ;CX=year
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MOV AL,BYTE PTR [WEEKDAY]
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RET
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$GET_DATE ENDP
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procedure $SET_DATE,NEAR ;System call 43
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; CX:DX valid date
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; Function:
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; Set current date
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; Returns:
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; AL = -1 date bad, = 0 OK
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MOV AL,-1 ;Be ready to flag error
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SUB CX,1980 ;Fix bias in year
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JC RET24 ;Error if not big enough
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CMP CX,119 ;Year must be less than 2100
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JA RET24
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OR DH,DH
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JZ RET24
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OR DL,DL
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JZ RET24 ;Error if either month or day is 0
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CMP DH,12 ;Check against max. month
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JA RET24
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PUSH SS
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POP DS
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ASSUME DS:DOSGROUP
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invoke DODATE
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RET24: RET
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$SET_DATE ENDP
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procedure $GET_TIME,NEAR ;System call 44
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; None
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; Function:
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; Get current time
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; Returns:
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; Time in CX:DX
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PUSH SS
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POP DS
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ASSUME DS:DOSGROUP
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invoke READTIME
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invoke get_user_stack ;Get pointer to user registers
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MOV [SI.user_DX],DX
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MOV [SI.user_CX],CX
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XOR AL,AL
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RET26: RET
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$GET_TIME ENDP
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procedure $SET_TIME,NEAR ;System call 45
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;Time is in CX:DX in hours, minutes, seconds, 1/100 sec.
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; CX:DX = Time
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; Function:
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; Set time
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; Returns:
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; AL = -1 time bad, = 0 OK
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MOV AL,-1 ;Flag in case of error
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CMP CH,24 ;Check hours
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JAE RET26
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CMP CL,60 ;Check minutes
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JAE RET26
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CMP DH,60 ;Check seconds
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JAE RET26
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CMP DL,100 ;Check 1/100's
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JAE RET26
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PUSH CX
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PUSH DX
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PUSH SS
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POP DS
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ASSUME DS:DOSGROUP
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MOV BX,OFFSET DOSGROUP:TIMEBUF
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MOV CX,6
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XOR DX,DX
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MOV AX,DX
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PUSH BX
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invoke SETREAD
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ASSUME ES:DOSGROUP
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PUSH DS
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LDS SI,[BCLOCK]
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ASSUME DS:NOTHING
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invoke DEVIOCALL2 ;Get correct day count
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POP DS
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ASSUME DS:DOSGROUP
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POP BX
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invoke SETWRITE
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POP WORD PTR [TIMEBUF+4]
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POP WORD PTR [TIMEBUF+2]
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LDS SI,[BCLOCK]
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ASSUME DS:NOTHING
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invoke DEVIOCALL2 ;Set the time
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XOR AL,AL
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RET
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$SET_TIME ENDP
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SUBTTL DISK R/W ROUTINES
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PAGE
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procedure $FCB_SEQ_READ,NEAR ; System call 20
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; Function:
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; Read next record from file to disk transfer address
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; Returns:
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; AL = 1 EOF record is empty
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; AL = 3 EOF record is partial zero filled
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; AL = 2 No room at disk transfer address
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; AL = 0 All OK
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invoke GETREC
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invoke LOAD
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JMP SHORT FINSEQ
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entry $FCB_SEQ_WRITE ; System call 21
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; Function:
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; Write next record to file from disk transfer address
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; Returns:
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; AL = 1 Disk full
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; AL = 2 No room in disk transfer segment
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; AL = 0 All OK
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invoke GETREC
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invoke STORE
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FINSEQ:
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JCXZ SETNREX
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ADD AX,1
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ADC DX,0
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JMP SHORT SETNREX
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entry $FCB_RANDOM_READ ; System call 33
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; Function:
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; Read record addressed by random record field from file to
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; disk transfer address
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; Returns:
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; AL = 1 EOF record is empty
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; AL = 3 EOF record is partial zero filled
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; AL = 2 No room at disk transfer address
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; AL = 0 All OK
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invoke GETRRPOS1
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invoke LOAD
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JMP SHORT FINRND
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entry $FCB_RANDOM_WRITE ; System call 34
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; Function:
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; Write record addressed by random record field to file from
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; disk transfer address
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; Returns:
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; AL = 1 Disk full
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; AL = 2 No room in disk transfer segment
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; AL = 0 All OK
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invoke GETRRPOS1
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invoke STORE
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JMP SHORT FINRND
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entry $FCB_RANDOM_READ_BLOCK ; System call 39
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; CX = Record count
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; Function:
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; Read CX records starting at random record field from file
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; to disk transfer address
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; Returns:
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; AL = 1 EOF record is empty
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; AL = 3 EOF record is partial zero filled
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; AL = 2 No room at disk transfer address
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; AL = 0 All OK
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; CX = Actual number of records read
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invoke GETRRPOS
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invoke LOAD
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JMP SHORT FINBLK
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entry $FCB_RANDOM_WRITE_BLOCK ; System call 40
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX Points to openned FCB
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; CX = Record count
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; Function:
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; Write CX records starting at random record field to file
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; from disk transfer address
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; If CX = 0 File is set to length determined from random record field
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; Returns:
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; AL = 1 Disk full
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; AL = 2 No room in disk transfer segment
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; AL = 0 All OK
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; CX = Actual number of records written
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invoke GETRRPOS
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invoke STORE
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FINBLK:
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invoke get_user_stack
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MOV [SI.user_CX],CX
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entry FINNOSAV
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JCXZ FINRND
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ADD AX,1
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ADC DX,0
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FINRND:
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MOV WORD PTR ES:[DI.fcb_RR],AX
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MOV ES:[DI.fcb_RR+2],DL
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OR DH,DH
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JZ SETNREX
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MOV ES:[DI.fcb_RR+3],DH ; Save 4 byte of RECPOS only if significant
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SETNREX:
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MOV CX,AX
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AND AL,7FH
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MOV ES:[DI.fcb_NR],AL
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AND CL,80H
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SHL CX,1
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RCL DX,1
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MOV AL,CH
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MOV AH,DL
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MOV ES:[DI.fcb_EXTENT],AX
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MOV AL,BYTE PTR [DSKERR]
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RET4:
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RET
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$FCB_SEQ_READ ENDP
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SUBTTL $FCB_DELETE -- SYSTEM CALL 19
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PAGE
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procedure $FCB_DELETE,NEAR ; System call 19
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX point to unopened FCB
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; Function:
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; Delete all matching entries
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; Returns:
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; AL = -1 if no entries matched, otherwise 0
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invoke MOVNAME
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ASSUME ES:DOSGROUP
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MOV AL,-1
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MOV BYTE PTR [FoundDel],AL
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JC RET4
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MOV AL,BYTE PTR [ATTRIB]
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AND AL,attr_hidden+attr_system+attr_directory+attr_volume_id+attr_read_only
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; Look only at hidden bits
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CMP AL,attr_hidden+attr_system+attr_directory+attr_volume_id+attr_read_only
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; All must be set
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JNZ NOTALL
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MOV CX,11
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MOV AL,"?"
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MOV DI,OFFSET DOSGROUP:NAME1
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REPE SCASB ; See if name is *.*
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JNZ NOTALL
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MOV BYTE PTR [DELALL],0 ; DEL *.* - flag deleting all
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NOTALL:
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invoke FINDNAME
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ASSUME DS:DOSGROUP
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MOV AL,-1
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JC RET4
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OR AH,AH ; Check if device name
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JS RET4 ; Can't delete I/O devices
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DELFILE:
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LES BP,[THISDPB]
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MOV AH,BYTE PTR [DELALL]
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PUSH DS
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LDS DI,[CURBUF]
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ASSUME DS:NOTHING
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TEST [Attrib],attr_read_only ; are we deleting RO files too?
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JNZ DoDelete ; yes
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TEST DS:[BX.dir_attr],attr_read_only
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JZ DoDelete ; not read only
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POP DS
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JMP SHORT DelNxt
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DoDelete:
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MOV BYTE PTR [FoundDel],0
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MOV [DI.BUFDIRTY],1
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MOV BYTE PTR [BX],AH
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MOV BX,[SI]
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POP DS
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ASSUME DS:DOSGROUP
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OR BX,BX
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JZ DELNXT
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CMP BX,ES:[BP.dpb_max_cluster]
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JA DELNXT
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invoke RELEASE
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DELNXT:
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invoke GETENTRY ; Registers need to be reset
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invoke NEXTENT
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JNC DELFILE
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CALL FLUSHRET1
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MOV AL,BYTE PTR [FoundDel]
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RET
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$FCB_DELETE ENDP
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SUBTTL $FCB_RENAME -- SYSTEM CALL 23; RENAME FILES
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PAGE
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ERRETJ: JMP ERRET
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procedure $FCB_RENAME,NEAR ; System call 23
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX point to a modified FCB (DS:DX+11H points to destination
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; name)
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; Function:
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; Rename all matching entries to indicated name
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; Returns:
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; AL = -1 if no entries matched, otherwise 0
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invoke MOVNAME
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ASSUME ES:DOSGROUP
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JC ERRETJ
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ADD SI,5
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MOV DI,OFFSET DOSGROUP:NAME2
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invoke LODNAME
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JC ERRETJ ; Report error if second name invalid
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invoke FINDNAME
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ASSUME DS:DOSGROUP
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JC ERRETJ
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OR AH,AH ; Check if I/O device name
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JS ERRETJ ; If so, can't rename it
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MOV SI,OFFSET DOSGROUP:NAME1
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MOV DI,OFFSET DOSGROUP:NAME3
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MOV CX,13
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REP MOVSB ; Copy name to search for --include attribute byte
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RENFIL:
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MOV DI,OFFSET DOSGROUP:NAME1
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MOV SI,OFFSET DOSGROUP:NAME2
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MOV CX,11
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NEWNAM:
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LODSB
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CMP AL,"?"
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JNZ NOCHG
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PUSH DS
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MOV DS,WORD PTR [CURBUF+2]
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MOV AL,[BX]
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POP DS
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NOCHG:
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STOSB
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INC BX
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LOOP NEWNAM
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INC DI
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MOV BYTE PTR [DI],attr_all ;Sets ATTRIB
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; Stop duplicates with any attributes
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invoke DEVNAME ; Check if giving it a device name
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JNC RENERR
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XOR AX,AX
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PUSH [LASTENT]
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invoke FINDENTRY ; See if new name already exists
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POP AX
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JNC RENERR ; Error if found
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LES BP,[THISDPB]
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invoke GETENT ; Re-read matching entry
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MOV DI,BX ; Leave BX,DX until call to NEXTENT
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MOV ES,WORD PTR [CURBUF+2]
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MOV SI,OFFSET DOSGROUP:NAME1
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MOV CX,11
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REP MOVSB ; Replace old name with new one
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MOV DI,WORD PTR [CURBUF]
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MOV ES:[DI.BUFDIRTY],1 ; Directory changed
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PUSH SS
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POP ES
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MOV SI,OFFSET DOSGROUP:NAME3
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MOV DI,OFFSET DOSGROUP:NAME1
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MOV CX,13 ; Include attribute byte
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REP MOVSB ; Copy name back into search buffer
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invoke NEXTENT
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JNC RENFIL
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JMP FLUSHRET1
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RENERR:
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CALL FLUSHRET1
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ERRET:
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MOV AL,-1
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RET
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$FCB_RENAME ENDP
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SUBTTL $FCB_OPEN -- SYSTEM CALL 15; OPEN A FILE
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PAGE
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procedure $FCB_OPEN,NEAR ; System call 15
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ASSUME DS:NOTHING,ES:NOTHING
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; Inputs:
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; DS:DX point to an unopened FCB
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; Function:
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; Open indicated file and fill in FCB
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; Returns:
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; AL = -1 if no entries matched, otherwise 0
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; FOR INTERNAL USE
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; [CURBUF+2]:SI and [CURBUF+2]:BX Preserved
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invoke GETFILE
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ASSUME DS:DOSGROUP,ES:NOTHING
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entry DOOPEN
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; Enter here to perform $FCB_OPEN on file already found
|
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; in directory. AH=device ID number, DS=CS, BX points to directory
|
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; entry in [CURBUF], SI points to First Cluster field, and
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; ES:DI point to the FCB to be opened. This entry point
|
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; is used by $FCB_CREATE.
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JC ERRET
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PUSH SI
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PUSH AX ; Save I/O driver number
|
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XOR AL,AL
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OR AH,AH
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JS OPENDEV
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MOV AL,[THISDRV]
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MOV DS,WORD PTR [CURBUF+2]
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ASSUME DS:NOTHING
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INC AX
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OPENDEV:
|
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STOSB
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XOR AX,AX
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IF ZEROEXT
|
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ADD DI,11
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STOSW ; Zero low byte of extent field if ZERPEXT only
|
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ELSE
|
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ADD DI,12 ; Point to high half of CURRENT BLOCK field
|
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STOSB ; Set it to zero (CP/M programs set low byte)
|
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ENDIF
|
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MOV AL,128 ; Default record size
|
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STOSW ; Set record size
|
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LODSW ; Get starting cluster
|
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MOV DX,AX ; Save it for the moment
|
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MOVSW ; Transfer size to FCB
|
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MOVSW
|
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MOV AX,[SI-8] ; Get date
|
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STOSW ; Save date in FCB
|
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MOV AX,[SI-10] ; Get time
|
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STOSW ; Save it in FCB
|
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POP AX ; Restore I/O driver number
|
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POP SI
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MOV AL,AH
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OR AL,40H ; Not dirty
|
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STOSB
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JS SAVDEVPT ; If device, go save pointer to it
|
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MOV AX,DX ; Restore starting cluster
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STOSW ; first cluster
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PUSH AX ; save cluster
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XOR AX,AX
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STOSW ; clus pos
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POP AX ; last cluster
|
||
STOSB
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MOV AL,AH
|
||
MOV AH,BYTE PTR [DIRSTART]
|
||
PUSH CX
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MOV CL,4
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SHL AH,CL
|
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OR AL,AH
|
||
STOSB
|
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MOV AX,[DIRSTART]
|
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MOV CL,4
|
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SHL AX,CL
|
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POP CX
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MOV AL,AH
|
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STOSB
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OPEN_RET:
|
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XOR AX,AX
|
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RET
|
||
|
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SAVDEVPT:
|
||
ASSUME DS:DOSGROUP
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LDS AX,[DEVPT]
|
||
ASSUME DS:NOTHING
|
||
STOSW
|
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MOV ES:[DI],DS
|
||
JMP SHORT OPEN_RET
|
||
$FCB_OPEN ENDP
|
||
|
||
SUBTTL $FCB_CLOSE -- SYSTEM CALL 16; CLOSE FILE
|
||
PAGE
|
||
procedure $FCB_CLOSE,NEAR ; System call 16
|
||
ASSUME DS:NOTHING,ES:NOTHING
|
||
|
||
; Inputs:
|
||
; DS:DX point to an opened FCB
|
||
; Function:
|
||
; Close the indicated file
|
||
; Returns:
|
||
; AL = -1 if disk has been changed, otherwise 0
|
||
|
||
MOV DI,DX
|
||
CMP BYTE PTR [DI],-1 ; Check for extended FCB
|
||
JNZ NORMFCB3
|
||
ADD DI,7
|
||
NORMFCB3:
|
||
TEST [DI.fcb_DEVID],devid_file_clean+devid_device
|
||
; Allow only dirty files
|
||
JNZ OKRET1 ; can't close I/O device or not written
|
||
invoke MOVNAMENOSET
|
||
JC BADCLOSE ; Bad file name
|
||
entry FCB_CLOSE_INNER
|
||
PUSH DX
|
||
PUSH DS
|
||
MOV SI,DX
|
||
MOV BX,[SI.fcb_LSTCLUS+1]
|
||
MOV CL,4
|
||
SHR BX,CL
|
||
PUSH BX
|
||
PUSH SS
|
||
POP DS
|
||
ASSUME DS:DOSGROUP
|
||
invoke FATREAD
|
||
POP BX
|
||
invoke SETDIRSRCH
|
||
invoke FINDENTRY
|
||
POP ES
|
||
POP DI
|
||
JC BADCLOSE
|
||
LDS BX,[CURBUF]
|
||
ASSUME DS:NOTHING
|
||
|
||
; note that SI points to dir_first...
|
||
|
||
OR BYTE PTR [SI-dir_first+dir_attr],attr_archive
|
||
MOV CX,ES:[DI.fcb_FIRCLUS]
|
||
MOV [SI-dir_first+dir_first],CX
|
||
MOV DX,ES:WORD PTR [DI.fcb_FILSIZ]
|
||
MOV [SI-dir_first+dir_size_l],DX
|
||
MOV DX,ES:WORD PTR [DI.fcb_FILSIZ+2]
|
||
MOV [SI-dir_first+dir_size_h],DX
|
||
MOV DX,ES:[DI.fcb_FDATE]
|
||
MOV [SI-dir_first+dir_date],DX
|
||
MOV DX,ES:[DI.fcb_FTIME]
|
||
MOV [SI-dir_first+dir_time],DX
|
||
MOV [BX.BUFDIRTY],1
|
||
PUSH SS
|
||
POP DS
|
||
ASSUME DS:DOSGROUP
|
||
FLUSHRET1:
|
||
LES BP,[THISDPB]
|
||
MOV AL,ES:[BP.dpb_drive]
|
||
invoke FLUSHBUF
|
||
OKRET1:
|
||
XOR AL,AL
|
||
RET
|
||
|
||
BADCLOSE:
|
||
MOV AL,-1
|
||
RET
|
||
$FCB_CLOSE ENDP
|
||
|
||
SUBTTL $FCB_CREATE -- SYSTEM CALL 22; MAKE AND OPEN A NEW FILE
|
||
PAGE
|
||
procedure $FCB_CREATE,NEAR ; System call 22
|
||
ASSUME DS:NOTHING,ES:NOTHING
|
||
|
||
; Inputs:
|
||
; DS:DX point to an unopened FCB
|
||
; Function:
|
||
; If file does not exist, create it and open it
|
||
; If file exists, free up its contents and open the file
|
||
; Returns:
|
||
; AL = -1 if file cannot be created, otherwise 0
|
||
|
||
invoke MOVNAME
|
||
ASSUME ES:DOSGROUP
|
||
JC ERRET3
|
||
MOV DI,OFFSET DOSGROUP:NAME1
|
||
MOV CX,11
|
||
MOV AL,"?"
|
||
REPNE SCASB
|
||
JZ ERRET3
|
||
MOV BYTE PTR [CREATING],-1
|
||
PUSH DX
|
||
PUSH DS
|
||
invoke FINDNAME
|
||
ASSUME DS:DOSGROUP
|
||
NWENTY:
|
||
LES BP,[THISDPB]
|
||
ASSUME ES:NOTHING
|
||
JNC EXISTENT
|
||
invoke BUILDDIR
|
||
JC ERRPOP
|
||
invoke GETENT ; Point at that free entry
|
||
JMP SHORT FREESPOT
|
||
ERRPOP:
|
||
POP DS
|
||
POP DX
|
||
ASSUME DS:NOTHING
|
||
ERRET3:
|
||
JMP SHORT BADCLOSE
|
||
|
||
entry NEWENTRY
|
||
POP DX ; Return address
|
||
POP ES ; ES
|
||
POP CX ; DI
|
||
PUSH DX
|
||
PUSH CX
|
||
PUSH ES
|
||
JMP NWENTY
|
||
|
||
EXISTENT:
|
||
ASSUME DS:DOSGROUP
|
||
JNZ ERRPOP ; Error if attributes don't match
|
||
OR AH,AH ; Check if file is I/O device
|
||
JS OPENJMP ; If so, no action
|
||
PUSH DS
|
||
LDS DI,[CURBUF]
|
||
ASSUME DS:NOTHING
|
||
MOV CX,[SI] ; Get pointer to clusters
|
||
MOV SI,[DI.BUFSECNO]
|
||
POP DS
|
||
ASSUME DS:DOSGROUP
|
||
JCXZ FREESPOT
|
||
CMP CX,ES:[BP.dpb_max_cluster]
|
||
JA FREESPOT
|
||
SUB BX,DI
|
||
PUSH BX
|
||
PUSH SI ; Save sector number
|
||
MOV BX,CX
|
||
invoke RELEASE ; Free any data already allocated
|
||
POP DX
|
||
XOR AL,AL
|
||
invoke GETBUFFR
|
||
POP BX
|
||
ADD BX,WORD PTR [CURBUF]
|
||
FREESPOT:
|
||
TEST BYTE PTR [ATTRIB],attr_volume_id
|
||
JZ NOTVOLID
|
||
CMP BYTE PTR [VOLID],0
|
||
JNZ ERRPOP ; Can't create a second volume ID
|
||
NOTVOLID:
|
||
MOV ES,WORD PTR [CURBUF+2]
|
||
MOV DI,BX
|
||
MOV SI,OFFSET DOSGROUP:NAME1
|
||
MOV CX,5
|
||
MOVSB
|
||
REP MOVSW
|
||
MOV AL,[ATTRIB]
|
||
STOSB
|
||
MOV CL,5
|
||
XOR AX,AX
|
||
REP STOSW
|
||
invoke DATE16
|
||
XCHG AX,DX
|
||
STOSW
|
||
XCHG AX,DX
|
||
STOSW
|
||
XOR AX,AX
|
||
PUSH DI
|
||
STOSW
|
||
STOSW
|
||
STOSW
|
||
MOV SI,WORD PTR [CURBUF]
|
||
MOV ES:[SI.BUFDIRTY],1
|
||
LES BP,[THISDPB]
|
||
MOV AL,ES:[BP.dpb_drive]
|
||
PUSH AX
|
||
PUSH BX
|
||
invoke FLUSHBUF
|
||
POP BX
|
||
POP AX
|
||
POP SI
|
||
MOV AH,AL ; Get I/O driver number back
|
||
OPENJMP:
|
||
CLC ; Clear carry so OPEN won't fail
|
||
POP ES
|
||
POP DI
|
||
ASSUME ES:NOTHING
|
||
JMP DOOPEN
|
||
$FCB_CREATE ENDP
|
||
|
||
do_ext
|
||
|
||
CODE ENDS
|
||
END
|
||
|
||
|