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Bring in CubeE sources Resource forks are included only for .rsrc files. These are DeRezzed into their data fork. 'ckid' resources, from the Projector VCS, are not included. The Tools directory, containing mostly junk, is also excluded.
2017-09-17 09:09:04 +00:00
;
; File: FXM.a
;
; Contains: These routines provide functions used to access and maintain
; file extents.
;
; Written by: Bill Bruffey
;
; Copyright: <09> 1985-1992 by Apple Computer, Inc., all rights reserved.
;
; Change History (most recent first):
;
; <SM1> 4/1/92 kc Export XFFlush.
; <09> Pre-SuperMario comments follow <20>
; <2> 9/10/91 JSM Add a header.
; <1.2> 3/2/89 DNF removed references to forROM; HFS now builds identically for ram
; or rom
; <1.1> 11/10/88 CCH Fixed Header.
; <1.0> 11/9/88 CCH Adding to EASE.
; <<3C>1.1> 9/23/88 CCH Got rid of inc.sum.d and empty nFiles
; <1.0> 2/11/88 BBM Adding file for the first time into EASE<53>
; 3/24/87 BB Fixed bug in MapFBlock which was incorrectly calculating the
; starting logical block number (a word value was being added
; rather than a long word value). This fix rolls in patches S118
; in ROMAllFix and PM119 in ROM75Fix.
; 10/27/86 BB Vectored MapFBlock and XFSearch routines.
; 9/25/86 BB Updated to use new MPW equate files.
; 1/9/86 BB Added use of an option flags byte to TruncateFile. An option
; flag was defined to indicate 'truncate to end of extent'
; replacing the current use of the FlushOnly flag for that
; purpose.
; 1/8/86 BB Added use of an option flags byte to ExtendFile. Two flags were
; defined indicating 'all or nothing' and 'contiguous' allocation
; requests. The ROM75 SetEOF patch supporting the 'all or nothing'
; allocation was integrated into the code.
; 10/28/85 BB TruncateFile now truncates based on the current state of the
; "FlushOnly" flag. If FlushOnly is set, the file is truncated at
; the end of the extent containing the new PEOF. If FlushOnly is
; not set, the file is truncated to the new PEOF rounded to the
; next allocation block. Truncate File now sets the PEOF in the
; FCB once new PEOF has been successfully mapped.
; 10/25/85 BB Added common FX set up routine. Added vectors for ROM versions.
; 10/22/85 PWD Fixed TruncateFile bug when starting deallocation in FCB ext.
; rec.
; 10/17/85 BB Replaced extent record BlockMoves with MOVE.L loops. XRUpdate
; now returns updated hints. ExtendFile no longer requires a
; re-map of the PEOF in order to add more than one extent.
; 10/16/85 BB Cleaned up some.
; 10/2/85 LAK Code-saving pass.
; 10/1/85 LAK MapFBlock now returns D0 as result code rather than end block+1.
; 9/26/85 PWD Fixed bug in MapFBlock w. >512 byte allocation blocks
; 9/23/85 BB Modified MapFBlock to save low level error code before calling
; SysError.
; 9/19/85 BB Fixed another bug in TruncateFile, D3 was not being set up
; following a truncation of the last extent in the FCB.
; 9/17/85 BB Fixed bug in TruncateFile, was not saving BTree hints.
; 8/27/85 BB Added support for contiguous allocation.
; 7/10/85 BB Added XFFlush subroutine and the necessary calls to it.
; 6/27/85 BB Reworked MapFBlock. Added check in DeAllocFile to verify the
; CNode type.
; 6/22/85 PWD Fixed MapFBlock bug in computation of available bytes
; 5/30/85 BB Modified TruncateFile to handle a new PEOF = 0.
; 5/20/85 BB Fixed bug in XFSearch, it wasn't checking for 'not found' result
; code from BTGetRecord.
; 5/15/85 BB Fixed bug in ExtendFile, return code was getting trashed.
; 5/13/85 BB Fixed PEOF stuff.
; 4/29/85 BB Rewrote from Gary's initial version and added support for FCB
; resident extents.
;
;_________________________________________________________________________________
;
; External
; Routines: DeAllocFile - Deallocates all disk space for a given file.
; ExtendFile - Extends the disk space allocated to a file.
; FXMKeyCmp - Compares two extent file keys.
; MapFBlock - Maps a file position into a physical disk
; address.
; TruncateFile - Truncates the disk space allocated to a file.
;
; Internal
; Subroutines: XFFlush - Flushes the extent BTree file.
; XFSearch - Searches extent file (including the FCB resident
; extent record) for a given file position.
; XRSearch - Searches an extent record for a given file
; allocation block number (FABN).
; XRUpdate - Updates an extent record.
;
;_________________________________________________________________________________
BLANKS ON
STRING ASIS
PRINT OFF
LOAD 'StandardEqu.d'
PRINT ON
PRINT NOGEN
FXM PROC EXPORT
EXPORT DeAllocFile,Extendfile,FXMKeyCmp,MapFBlock,TruncateFile,XFFlush
EXPORT vDeallocFile,vExtendFile,vMapFBlock,vTruncateFile,vXFSearch ;<27Oct86>
IMPORT BTGetRecord,BTDelete,BTFlush,BTInsert,BtSearch,BTUpdate
IMPORT BlkAlloc,BlkDealloc
IMPORT CMGetCN
IMPORT MarkVCB,FlushMDB
;_________________________________________________________________________________
;
; Routine: DeallocFile (Deallocate File)
;
; Function: De-allocates all disk space allocated to a specified file.
; The space occupied by both forks is deallocated.
;
; Input: A2.L - VCB pointer
; D0.W - ParID
; A0.L - CName pointer
;
; Output: D0.W - result code
; 0 = ok
; other = error
;
; Called by: DeleteFile
;
; Note: The extent records resident in catalog are not updated by DeallocFile.
; DeleteFile deletes the catalog record for the file after calling
; DeallocFile.
;_________________________________________________________________________________
DeallocFile
MOVE.L jDeallocFile,-(SP) ; jump table entry for vDeallocFile <25Oct85>
RTS ; go there <25Oct85>
vDeallocFile ; 'vectored' DeallocFile routine <25Oct85>
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1-D7/A0-A1/A3-A4,-(A6) ; save registers
BSR FXSetUp ; set up common stuff <25Oct85>
MOVEA.L A0,A3 ; A3 = ptr to Cname
MOVE.L D0,D7 ; D7 = ParID
CLR.B D6 ; D6 = initial fork type (0 = data fork)
; Locate catalog record for file
DFFkLoop
CLR.W D4 ; initial FABN
MOVEA.L A3,A0 ; ptr to Cname
MOVE.L D7,D0 ; ParID
CLR.L D2 ; no hint
JSR CMGetCN ; locate catalog record
BNE DFExit1 ; didn't get it ->
CMPI.B #CMFilCN,cdrType(A1) ; file CNode?
BEQ.S @1 ; yes ->
MOVEQ #CMnotfound,D0 ; result = 'not found' <02Oct85>
BNE DFExit1 ; exit ->
@1 MOVE.L filFlNum(A1),D5 ; D5 = file number
LEA FXVxkrOff(A4),A0 ; ptr to FXM key buffer
CLR.W xkrFABN(A0) ; indicate catalog resident extent record
TST.B D6 ; deleting the data fork?
BNE.S @2 ; no ->
LEA filExtRec(A1),A1 ; position to data fork extent record
BRA.S DFCopyRec ; copy extent record ->
@2 LEA filRExtRec(A1),A1 ; position to resource fork extent record
BRA.S DFCopyRec ; copy extent record ->
;
; set up key for next extent file record
;
DFRecLoop
LEA FXVxkrOff(A4),A0 ; A0 points to FXM key buffer
MOVE.B #lenxkr-1,xkrKeyLen(A0) ; key length
MOVE.B D6,xkrFkType(A0) ; fork type
MOVE.L D5,xkrFNum(A0) ; file number
MOVE.W D4,xkrFABN(A0) ; file alloc block number
;
; get the next extent record
;
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
CLR.L D2 ; no hint
JSR BTSearch ; find the record
BEQ.S DFCopyRec ; found it ->
CMPI.W #BTnotfound,D0 ; record not found?
BEQ.S DFNxtFork ; yes, done with this fork ->
BRA.S DFExit1 ; error ->
;
; copy extent data to FXM buffer
;
DFCopyRec
LEA FXVxdrOff(A4),A0 ; dest = xdr buffer in fxm vars <17Oct85>
MOVEQ #(lenxdr/4)-1,D0 ; loop index in long words <17Oct85>
@1 MOVE.L (A1)+,(A0)+ ; Copy the record <17Oct85>
DBRA D0,@1 ; <17Oct85>
;
; release extents for this record
;
LEA FXVxdrOff(A4),A1 ; A1 = ptr to extent record <17Oct85>
CLR.W D1 ; offset to 1st extent
DFRelExt
MOVE.W xdrStABN(A1,D1.W),D2 ; starting alloc blk number
MOVE.W xdrNumABlks(A1,D1.W),D3 ; number of alloc blks
BEQ.S DFDelRec ; extent not used, delete the record ->
JSR BlkDealloc ; deallocate the space
BNE.S DFExit1 ; error ->
ADD.W D3,D4 ; bump FABN to beg of next extent
ADDQ.W #lenExt,D1 ; bump to next extent
CMPI.W #maxExtOff,D1 ; past last extent?
BLE.S DFRelExt ; no, release next one ->
;
; delete extent record
;
DFDelRec
LEA FXVxkrOff(A4),A0 ; A0 points to search key
TST.W xkrFABN(A0) ; catalog resident record?
BEQ.S @1 ; yes, nothing to delete ->
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
JSR BTDelete ; delete the record
BNE.S DFExit1 ; error ->
@1 TST.W D3 ; end with null extent entry?
BNE.S DFRecLoop ; no, get next record for same fork ->
;
; finished with current fork, check for another one
;
DFNxtFork
NOT.B D6 ; just finished resource fork ($FF -> $00)? <02Oct85>
BNE DFFkLoop ; $00 -> $FF: release space for resource fork <02Oct85>
;
; clean up and exit
;
DFExit
CLR.W D0 ; result = ok
BSR XFFlush ; flush the extent file
DFExit1
ADD #lenFXVars,A6 ; de-allocate memory for FXM vars <02Oct85>
MOVEM.L (A6)+,D1-D7/A0-A1/A3-A4 ; restore regs
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set up condition codes
RTS ; exit DeallocFile
;_________________________________________________________________________________
;
; Routine: Extendfile
;
; Function: Extends the disk space allocated to a file.
;
; Input: A2.L - VCB pointer
; A1.L - pointer to FCB array
; D1.W - file refnum
; D3.B - option flags
; EFContig - force contiguous allocation
; EFAll - allocate all requested bytes or none
; D4.L - number of additional bytes to allocate
;
; Output: D0.W - result code
; 0 = ok
; -n = IO error
; D6.L - number of bytes allocated
;
; Called by: FileAloc,FileWrite,SetEof
;
; Note: ExtendFile updates the PEOF in the FCB.
;_________________________________________________________________________________
ExtendFile
MOVE.L jExtendFile,-(SP) ; jump table entry for vExtendFile <25Oct85>
RTS ; go there <25Oct85>
vExtendFile ; 'vectored' ExtendFile routine <25Oct85>
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1-D5/D7/A0-A4,-(A6) ; save regs
BSR FXSetUp ; set up common stuff <25Oct85>
LEA 0(A1,D1.W),A3 ; A3 = FCB pointer
MOVE.L FCBPLen(A3),-(A6) ; save previous PEOF
;
; Set up for type of allocation requested.
;
BTST #EFAll,D3 ; all or nothing requested? <08Jan86>
BEQ.S @1 ; no -> <08Jan86>
MOVE.W VCBFreeBks(A2),D0 ; Compute free space in bytes <08Jan86>
MULU VCBAlBlkSiz+2(A2),D0 ; <08Jan86>
CMP.L D4,D0 ; Compare against requested space <08Jan86>
BHS.S @1 ; If enough space free, go on -> <08Jan86>
MOVEQ #DskFulErr,D0 ; result = 'disk full' <08Jan86>
BRA EFExit1 ; exit ExtendFile -> <08Jan86>
@1 BSET #FXVTContig,FXVFlags(A4) ; 1st try contig allocation <27Aug85>
BTST #EFContig,D3 ; forced contiguous requested? <08Jan86>
BEQ.S @2 ; no -> <02Sep85>
BSET #FXVFContig,FXVFlags(A4) ; yes, set flag <27Aug85>
@2 MOVE.L VCBAlBlkSiz(A2),D0 ; round the # of bytes requested
ADD.L D0,D4 ;
SUBQ.L #1,D4 ;
DIVU D0,D4 ;
MULU D0,D4 ; ...up to next alloc blk
;
; locate the extent mapping the new PEOF - 1 (last byte in file)
;
EFLocExt
MOVE.L FCBPLen(A3),D0 ; current PEOF
ADD.L D4,D0 ; + # of bytes requested = new PEOF
SUBQ.L #1,D0 ; new PEOF - 1 = last byte in file
BSR XFSearch ; locate the extent
BNE.S @1 ; didn't find it ->
ADD.L D4,FCBPLen(A3) ; update PEOF
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty
BRA EFExit ; all done ->
@1 CMPI.W #FXRangeErr,D0 ; out of range?
BNE EFExit1 ; no, some error ->
MOVE.L D2,D7 ; D7 = BTree hint
MOVE.W D3,D6 ; D6 = ending FABN +1
;
; adjust PEOF to end of extent
;
MOVE.W D6,D0 ; (ending FABN + 1)
MULU VCBAlBlkSiz+2(A2),D0 ; in bytes = max PEOF for extent
SUB.L FCBPlen(A3),D0 ; PEOF already at end of extent?
BEQ.S EFAddSpace ; yes ->
ADD.L D0,FCBPlen(A3) ; no, adjust PEOF to end of extent
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty
SUB.L D0,D4 ; adjust remaining count
;
; allocate additional disk space
;
EFAddSpace
MOVE.W xdrStABN(A1,D1.W),D5 ; starting alloc blk number
ADD.W xdrNumABlks(A1,D1.W),D5 ; + # of blks = last blk +1
@1 MOVE.W D5,D2 ; preferred starting blk = last blk + 1
BTST #FXVTContig,FXVFlags(A4) ; are we trying for contig <27Aug85>
SNE D3 ; yes, set flag for BlkAlloc <27Aug85>
JSR BlkAlloc ; allocate the disk space <27Aug85>
BEQ.S EFExtExt ; got it -> <27Aug85>
CMPI.W #DskFulErr,D0 ; disk full error? <27Aug85>
BNE EFExit1 ; no, some other error -> <27Aug85>
BCLR #FXVTContig,FXVFlags(A4) ; did we just try for contig? <27Aug85>
BEQ EFExit1 ; no, must be out of space -> <27Aug85>
BTST #FXVFContig,FXVFlags(A4) ; forced contig requested? <27Aug85>
BNE EFExit1 ; yes, could't get it -> <27Aug85>
BRA.S @1 ; try non-contig -> <27Aug85>
;
; got some space, see if current extent can be extended
;
EFExtExt
CMP.W D2,D5 ; get preferred space?
BNE.S EFAddExt ; no, must add an extent ->
ADD.W D3,xdrNumABlks(A1,D1.W) ; add new blks to current extent
BRA.S EFUpdExt ; use common code -> <17Oct85>
;
; add a new extent entry
;
EFAddExt
TST.W xdrNumABlks(A1,D1.W) ; current extent null?
BEQ.S @1 ; yes, use it ->
ADDQ.W #lenExt,D1 ; bump to next extent
CMPI.W #maxExtOff,D1 ; past last extent?
BGT.S EFNewRec ; yes, must add new record? ->
@1 MOVE.W D2,xdrStABN(A1,D1.W) ; set starting alloc blk #
MOVE.W D3,xdrNumABlks(A1,D1.W) ; ...and # of blks
;
; update the extent record
;
EFUpdExt
MOVE.L D7,D2 ; BTree hint
BSR XRUpdate ; update the extent record
BNE EFExit1 ; error ->
MOVE.L D2,D7 ; D7 = new hint <17Oct85>
BRA.S EFUpdFCB ; go update FCB ->
;
; add a new extent record
;
EFNewRec
MOVE.L FCBFlNm(A3),D5 ; D5 = file number
CMPI.L #FSXtCNID,D5 ; mapping the extents file?
BNE.S @1 ; no ->
MOVEQ #FXOvFlErr,D0 ; result = 'extent file overflow' <16Oct85>
BRA.S EFExit1 ; exit ->
@1 LEA FXVxkrOff(A4),A0 ; point to FXM buffer
LEA FXVxdrOff(A4),A1 ;
MOVE.B #lenxkr-1,xkrKeyLen(A0) ; key length
CLR.B xkrFkType(A0) ;assume data fork
BTST #FCBRscBit,FCBMdRByt(A3) ; mapping resource fork?
SNE xkrFkType(A0) ; yes, set resource fork flag
MOVE.L D5,xkrFNum(A0) ; file number
MOVE.W D6,xkrFABN(A0) ; starting file allocation blk #
MOVE.W #(lenxdr/2)-1,D0 ; clear new extent record
@2 CLR.W (A1)+ ;
DBRA D0,@2 ;
LEA FXVxdrOff(A4),A1 ; restore ptr to xdr
CLR.W D1 ; offset to 1st extent in record
MOVE.W D2,xdrStABN(A1,D1.W) ; set starting alloc blk #
MOVE.W D3,xdrNumABlks(A1,D1.W) ; ...and # of blks
MOVE.L D1,-(A6) ; save D1 <17Oct85>
MOVE.W #lenxdr,D1 ; record length
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
JSR BTInsert ; insert the new record
MOVE.L (A6)+,D1 ; restore D1 <17Oct85>
TST.W D0 ; restore BTInsert result <17Oct85>
BNE.S EFExit1 ; error ->
MOVE.L D2,D7 ; D7 = new hint <17Oct85>
;
; finished with this extension, update FCB and see if more space is needed
;
EFUpdFCB
ADD.W D3,D6 ; update ending FABN + 1 <17Oct85>
MULU VCBAlBlkSiz+2(A2),D3 ; convert # of blks allocated to bytes
ADD.L D3,FCBPlen(A3) ; adjust PEOF to include new space
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty
SUB.L D3,D4 ; allocated enough space?
BGT EFAddSpace ; no, do it again -> <17Oct85>
ADD.L D4,FCBPLen(A3) ; adjust PEOF to alloc blk boundry
;
; clean up and exit
;
EFExit
CLR.W D0 ; result = ok
BSR XFFlush ; flush the extent file
EFExit1
MOVE.L FCBPLen(A3),D6 ; new PEOF
MOVE.L (A6)+,D1 ; - previous PEOF
SUB.L D1,D6 ; = # of bytes allocated
ADD #lenFXVars,A6 ; de-allocate memory for FXM vars <02Oct85>
MOVEM.L (A6)+,D1-D5/D7/A0-A4 ; restore regs
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set condition codes
RTS ; exit ExtendFile
;_________________________________________________________________________________
;
; Routine: FXMKeyCmp (FXM Key Compare)
;
; Function: Compares two extent file keys (a search key and a trial key).
;
; Input: A0.L - search key pointer
; A1.L - trial key pointer
;
; Output: D0.W - result code
; +n search key > trial key
; 0 search key = trial key
; -n search key < trial key
;_________________________________________________________________________________
FXMKeyCmp
MOVEM.L A0-A1,-(SP) ; save registers
MOVE.L 2(A0),D0 ; compare file ID's
CMP.L 2(A1),D0 ;
BHI.S KCIsGT ; search fileNum > trial fileNum ->
BCS.S KCIsLT ; search fileNum < trial fileNum -> <02Oct85>
;
; file ID's are equal, compare fork types
;
MOVE.B 1(A0),D0 ; Get search key fork type
CMP.B 1(A1),D0 ; Compare against trial fork type
BHI.S KCIsGT ; search key fork type > trial key fork type
BCS.S KCIsLT ; search key fork type < trial key fork type <02Oct85>
;
; fork types are equal; compare the starting block numbers
;
MOVE.W 6(A0),D0 ; compare block numbers
CMP.W 6(A1),D0 ;
BHI.S KCIsGT ; search block # > trial block # ->
BCS.S KCIsLT ; search block # < trial block # -> <02Oct85>
KCIsEQ
CLR.W D0 ; result = "equal"
BRA.S KCExit
KCIsLT
MOVE.W #-1,D0 ; result = "less than"
BRA.S KCExit
KCIsGT
MOVE.W #+1,D0 ; result = "greater than"
KCExit
MOVEM.L (sp)+,A0-A1 ; restore registers
TST.W D0 ; set up condition codes
RTS ; exit FXMKeyCmp
;_________________________________________________________________________________
;
; Routine: MapFBlock
;
; Function: Maps a file position into a physical disk address.
;
; Input: A2.L - VCB pointer
; (A1,D1.W) - FCB pointer
; D4.L - number of bytes desired
; D5.L - file position (byte address)
;
; Output: D3.L - physical start block
; D6.L - number of contiguous bytes available (up to D4 bytes)
; D0.L - result code <01Oct85>
; 0 = ok
; FXRangeErr = file position beyond mapped range <17Oct85>
; FXOvFlErr = extents file overflow <17Oct85>
; other = error <17Oct85>
;
; Called By: Log2Phys (read/write in place), Cache (map a file block).
;_________________________________________________________________________________
MapFBlock
MOVE.L jMapFBlock,-(SP) ; jump table entry for vMapFBlock <27Oct86>
RTS ; go there <27Oct86>
vMapFBlock ; 'vectored' MapFBlock routine <27Oct86>
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1-D2/D4-D5/D7/A0-A1/A3-A4,-(A6) ; save registers
BSR FXSetUp ; set up common stuff <25Oct85>
LEA 0(A1,D1.W),A3 ; A3 = FCB pointer
;
; locate the extent mapping the desired file position
;
MOVE.L D5,D0 ; file position
BSR XFSearch ; locate the extent
BNE.S MFExit ; exit on errors
LEA 0(A1,D1.W),A1 ; A1 = ptr to extent entry
MOVE.W D3,D1 ; D1 = beg FABN for extent
SUB.W xdrNumABlks(A1),D1 ;
MOVE.W D3,D2 ; D2 = end FABN in extent + 1
;
; determine end of available space (PEOF or end of extent)
;
MULU VCBAlBlkSiz+2(A2),D2 ; convert end FABN + 1 to file pos
MOVE.L FCBPLen(A3),D0 ; get PEOF
CMP.L D0,D2 ; end of extent > PEOF?
BLE.S @1 ; no, use end of extent ->
MOVE.L D0,D2 ; yes, use PEOF
@1 DIVU VCBAlBlkSiz+2(A2),D2 ; D2 = end of avail space ( end FABN + 1)
;
; set up some constants
;
MOVE.L VCBAlBlkSiz(A2),D6 ; D6 = # blks per alloc blk
DIVU #512,D6 ;
MOVEQ #0,D7 ; D7 = start blk # for alloc blks
MOVE.W VCBAlBlSt(A2),D7 ;
;
; calculate physical start block
;
MOVE.L D5,D3 ; file position / alloc blk size
DIVU VCBAlBlkSiz+2(A2),D3 ; = FABN mapping file position
SWAP D3 ; Get remainder in low word <PWD 26Sep85>
MOVEQ #0,D0 ; Clear top word to get remainder as long <PWD 26Sep85>
MOVE.W D3,D0 ; Compute block offset within alloc block <PWD 26Sep85>
LSR.L #8,D0 ; 'divide' by 256 <PWD 26Sep85>
LSR.L #1,D0 ; and again by 2 to get size in phys. blocks <PWD 26Sep85>
SWAP D3 ; Restore D3 for use <PWD 26Sep85>
SUB.W D1,D3 ; - beg FABN = alloc blk delta
ADD.W xdrStABN(A1),D3 ; + starting ABN = ABN mapping file pos
MULU D6,D3 ; convert to physical block #
ADD.L D0,D3 ; Offset in physical blocks within alloc. blk <24Mar87>
ADD.L D7,D3 ;
;
; calculate number of available bytes
;
MOVE.W D2,D6 ; end FABN + 1 * alloc blk size
MULU VCBAlBlkSiz+2(A2),D6 ; = ending file pos + 1
SUB.L D5,D6 ; - file position = size avail
CMP.L D4,D6 ; compare with desired number
BCS.S mFBlockOK ; < D4 bytes, leave it alone <02Oct85>
MOVE.L D4,D6 ; > D4 bytes, set to D4 bytes
mFBlockOK MOVEQ #0,D0 ; we're ok <01Oct85>
;
; clean up and exit
;
MFExit
ADD #lenFXVars,A6 ; de-allocate memory for FXM vars <02Oct85>
MOVEM.L (A6)+,D1-D2/D4-D5/D7/A0-A1/A3-A4 ; restore registers
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set CCR for result <01Oct85>
RTS ; exit MapFBlock
;_________________________________________________________________________________
;
; Routine: TruncateFile
;
; Function: Truncates the disk space allocated to a file. The file space is
; truncated a specified new PEOF rounded up to the next allocation block
; boundry. If the 'TFTrunExt' option is specified, the file is truncated
; to the end of the extent containing the new PEOF.
;
; Input: A2.L - VCB pointer
; A1.L - pointer to FCB array
; D1.W - file refnum
; D2.B - option flags
; TFTrunExt - truncate to the extent containing new PEOF
; D3.L - new PEOF
;
; Output: D0.W - result code
; 0 = ok
; -n = IO error
;
; Note: TruncateFile updates the PEOF in the FCB.
;_________________________________________________________________________________
TruncateFile
MOVE.L jTruncateFile,-(SP) ; jump table entry for vTruncateFile <25Oct85>
RTS ; go there <25Oct85>
vTruncateFile ; 'vectored' TruncateFile routine <25Oct85>
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1-D7/A0-A4,-(A6) ; save registers
BSR FXSetUp ; set up common stuff <25Oct85>
LEA 0(A1,D1.W),A3 ; A3 = FCB pointer
MOVE.B D2,D6 ; D6 = option flags <09Jan86>
;
; locate the extent mapping the last byte of the truncated file
;
TFLocExt
MOVE.L D3,D5 ; D5 = new PEOF
MOVE.L VCBAlBlkSiz(A2),D0 ; round the new PEOF
ADD.L D0,D5 ;
SUBQ.L #1,D5 ;
DIVU D0,D5 ;
MULU D0,D5 ; ...up to next alloc blk
MOVE.L D5,D0 ; new PEOF - 1 = last byte in file
SUBQ.L #1,D0 ;
BGE.S @1 ; new PEOF > 0 ->
MOVE.L D5,FCBPlen(A3) ; update PEOF in FCB <28Oct85>
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty <28Oct85>
SUBA.L A0,A0 ; indicate FCB resident record
MOVEQ #0,D7 ; no hint
LEA FCBExtRec(A3),A1 ; point to FCB extent record
CLR.W D4 ; last FABN in extent + 1
BRA TFRelExt ; release all extents -> <28Oct85>
@1 BSR XFSearch ; locate the extent
BNE TFExit1 ; error ->
MOVE.L D2,D7 ; D7 = BTree hint
MOVE.W D3,D4 ; D4 = last FABN in extent + 1
MOVE.L D5,FCBPlen(A3) ; update PEOF in FCB <28Oct85>
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty <28Oct85>
BTST #TFTrunExt,D6 ; truncate to end of extent? <09Jan86>
BEQ.S TFTrunPEOF ; no, truncate to new PEOF -> <09Jan86>
MOVE.W xdrNumABlks(A1,D1.W),D3 ; D3 = # of blks in extent <28Oct85>
BRA TFRelRExt ; release remaining extents in record -> <28Oct85>
;
; truncate extent containing new PEOF
;
TFTrunPEOF
MOVE.L D5,D0 ; new PEOF - 1 (last byte in file)
SUBQ.L #1,D0 ;
DIVU VCBAlBlkSiz+2(A2),D0 ; / alloc blk size = last FABN in file
SUB.W D0,D3 ; (last extent FABN +1) - (last file FABN)
SUBQ.W #1,D3 ; - 1 = # to deallocate
BEQ.S @1 ; nothing to deallocate ->
MOVE.W xdrStABN(A1,D1.W),D2 ; starting ABN
ADD.W xdrNumABlks(A1,D1.W),D2 ; + # alloc blks in extent
SUB.W D3,D2 ; - # to dealloc = starting ABN
JSR BlkDealloc ; deallocate the space
BNE TFExit1 ; error ->
@1 MOVE.W D3,D0 ; D0 = # of blks deallocated <19Sep85>
MOVE.W xdrNumABlks(A1,D1.W),D3 ; D3 = orig # of blks <19Sep85>
SUB.W D0,xdrNumABlks(A1,D1.W) ; update # of blks in extent <19Sep85>
BNE.S TFRelRExt ; extent not empty ->
CLR.W xdrStABN(A1,D1.W) ; set extent null
BRA.S TFRelRExt ; release remaining extents in record ->
;
; get the next extent record in BTree
;
TFLoop
LEA FXVxkrOff(A4),A0 ; A0 points to search key buffer
MOVE.B #lenxkr-1,xkrKeyLen(A0) ; key length
BTST #FCBRscBit,FCBMdRByt(A3) ; mapping resource fork? <09Jan86>
SNE xkrFkType(A0) ; yes, indicate resource fork <09Jan86>
MOVE.L FCBFlNm(A3),xkrFNum(A0) ; file number
MOVE.W D4,xkrFABN(A0) ; file alloc block number
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
CLR.L D2 ; no hint
JSR BTSearch ; find the record
BEQ.S @1 ; found it ->
CMPI.W #BTnotfound,D0 ; record not found?
BEQ.S TFExit ; yes, all done -> <28Oct85>
BRA.S TFExit1 ; error ->
@1 MOVE.L D2,D7 ; save hint in D7 <17Sep85>
LEA FXVxdrOff(A4),A0 ; dest = xdr buffer in fxm vars <17Oct85>
MOVEQ #(lenxdr/4)-1,D0 ; loop index in long words <17Oct85>
@2 MOVE.L (A1)+,(A0)+ ; Copy the record into FXM buffer <17Oct85>
DBRA D0,@2 ; <17Oct85>
LEA FXVxkrOff(A4),A0 ; A0 = ptr to search key <28Oct85>
LEA FXVxdrOff(A4),A1 ; A1 = ptr to extent record <28Oct85>
;
; release extents for this record
;
TFRelExt
CLR.W D1 ; offset to 1st extent <22Oct85>
TFRelNxt
MOVE.W xdrStABN(A1,D1.W),D2 ; starting alloc blk number
MOVE.W xdrNumABlks(A1,D1.W),D3 ; number of alloc blks
BEQ.S TFUpdRec ; extent not used, update the record ->
JSR BlkDealloc ; deallocate the space
BNE.S TFExit1 ; error ->
CLR.L xdrStABN(A1,D1.W) ; set the extent null
ADD.W D3,D4 ; bump FABN to beg of next extent
TFRelRExt
ADDQ.W #lenExt,D1 ; bump to next extent
CMPI.W #maxExtOff,D1 ; past last extent?
BLE.S TFRelNxt ; no, release next one ->
;
; update extent record
;
TFUpdRec
TST.W xdrNumABlks(A1) ; 1st extent null?
BEQ.S @1 ; yes, delete record ->
MOVE.L D7,D2 ; BTree hint
BSR XRUpdate ; update the record
BRA.S @2 ;
@1 MOVE.L A0,D0 ; FCB resident record?
BEQ.S @2 ; yes, nothing to delete ->
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
JSR BTDelete ; delete the record
BNE.S TFExit1 ; error ->
@2 TST.W D3 ; end with null extent entry?
BNE TFLoop ; no, continue with next record ->
;
; clean up and exit
;
TFExit
CLR.W D0 ; result = ok
BSR.S XFFlush ; flush the extent file <02Oct85>
TFExit1
ADD #lenFXVars,A6 ; de-allocate memory for FXM vars <02Oct85>
MOVEM.L (A6)+,D1-D7/A0-A4 ; restore registers
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set condition codes
RTS ; exit TruncateFile
;_________________________________________________________________________________
;
; Internal Subroutines
;_________________________________________________________________________________
;__________________________________________________________________________________
;
; Subroutine: FXSetUp (FXM Set Up)
;
; Function: Sets up for all FXM calls. Space for the FXM variable storage area
; (FXVars) is allocated on the A6 stack. The status flags in FXVars
; are also cleared.
;
; Input: none
;
; Output: A4.L - pointer to FXVars
;__________________________________________________________________________________
FXSetUp
SUB #lenFXVars,A6 ; allocate memory for FXM vars <25Oct85>
MOVEA.L A6,A4 ; A4 = pointer to FXM vars <25Oct85>
CLR.B FXVFlags(A4) ; clear all flags <25Oct85>
RTS ; exit FXSetUp <25Oct85>
;_________________________________________________________________________________
;
; Subroutine: XFFlush (Extent File Flush)
;
; Function: Flushes the extent file for a specified volume.
;
;
; Input: A2.L - VCB pointer
;
; Output: D0.W - result code
; 0 = ok
; other = error
;_________________________________________________________________________________
XFFlush
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1/A1,-(A6) ; save registers
MOVE.W VCBXTRef(A2),D1 ; D1 = refnum of extent file
MOVE.W D1,D0 ; flush the extent BTree
JSR BTFlush ;
BNE.S FFExit1 ; error ->
MOVEA.L FCBSPtr,A1 ; FCB dirty?
BTST #FCBModBit,FCBMdRByt(A1,D1.W) ;
BEQ.S FFExit ; no, all done ->
JSR MarkVCB ; Mark the VCB dirty
JSR FlushMDB ; flush the MDB
BNE.S FFExit1 ; error ->
FFExit
CLR.W D0 ; result ='ok'
FFExit1
MOVEM.L (A6)+,D1/A1 ; restore registers
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set condition codes
RTS ; exit XFFlush
;_________________________________________________________________________________
;
; Subroutine: XFSearch (Extent File Search)
;
; Function: Searches extent file (including the FCB resident extent record)
; for the extent mapping a given file position.
;
; Input: A2.L - VCB pointer
; A3.L - FCB pointer
; A4.L - pointer to FXM vars
; D0.L - file position (byte address)
;
; Output: D0.W - result code
; 0 = ok
; FXRangeErr = file position beyond mapped range
; other = error
; A0.L - pointer to extent key record (xkr)
; 0 = FCB resident extent record
; A1.L - pointer to extent data record(xdr)
; D1.L - offset to extent entry in xdr
; result = 0, offset to extent mapping desired FABN
; result = FXRangeErr, offset to last extent in record
; D2.L - BTree hint for extent record
; D3.W - ending FABN +1
;_________________________________________________________________________________
XFSearch
MOVE.L jXFSearch,-(SP) ; jump table entry for vXFSearch <27Oct86>
RTS ; go there <27Oct86>
vXFSearch ; 'vectored' XFSearch routine <27Oct86>
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D4-D6,-(A6) ; save regs
MOVE.L D0,D4 ; D4 = file position to be mapped
DIVU VCBAlBlkSiz+2(A2),D4 ; convert to FABN
MOVE.L FCBFlNm(A3),D5 ; D5 = file number
;
; search FCB extent record first
;
FSSchFCB
SUBA.L A0,A0 ; indicate FCB resident record
MOVEQ #0,D2 ; no hint
LEA FCBExtRec(A3),A1 ; point to extent record
MOVE.W D4,D0 ; desired FABN
CLR.W D3 ; starting FABN
BSR XRSearch ; search record for extent entry
BEQ FSExit ; found it ->
CMP.W #maxExtOff,D1 ; end before last extent entry?
BLT FSExit1 ; yes, no more extents ->
TST.W xdrNumABlks(A1,D1.W) ; end with a null extent?
BEQ FSExit1 ; yes, no more extents ->
CMPI.L #FSXtCNID,D5 ; mapping the extents file?
BEQ FSExit1 ; yes, no more extents ->
;
; locate desired record in extents file
;
FSSchFile
LEA FXVxkrOff(A4),A0 ; A0 = ptr to key buffer
MOVE.B #lenxkr-1,xkrKeyLen(A0) ; key length
BTST #FCBRscBit,FCBMdRByt(A3) ; mapping resource fork?
SNE D6 ; yes, set resource fork flag <02Oct85>
MOVE.B D6,xkrFkType(A0) ; D6 = fork flag <02Oct85>
MOVE.L D5,xkrFNum(A0) ; file number
MOVE.W D4,xkrFABN(A0) ; desired file allocation blk #
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
CLR.L D2 ; no hint
JSR BTSearch ; search BTree for extent record
BEQ.S FSCopyRec ; a direct hit ->
CMPI.W #BTnotfound,D0 ; result = 'not found'?
BNE.S FSExit1 ; no, error ->
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
MOVEQ #-1,D1 ; indicate previous record
JSR BTGetrecord ; get previous extent record
BEQ.S @1 ; got it ->
CMPI.W #BTnotfound,D0 ; result = 'not found'?
BEQ.S FSMissed ; yes, no extent record ->
BRA.S FSExit1 ; error ->
@1 CMP.L xkrFNum(A0),D5 ; same file?
BNE.S FSMissed ; no ->
CMP.B xkrFkType(A0),D6 ; same fork?
BEQ.S FSCopyRec ; yes, we got it ->
;
; didn't find extent record in BTree, return pointing to last extent in FCB
;
FSMissed
SUBA.L A0,A0 ; indicate FCB resident record
MOVEQ #0,D2 ; no hint
LEA FCBExtRec(A3),A1 ; point to FCB extent record
MOVE.W #maxExtOff,D1 ; the last extent
MOVEQ #FXRangeErr,D0 ; result = 'range error' <02Oct85>
BRA.S FSExit1 ; exit ->
;
;found extent record, copy the key and data records into FXM vars
;
FSCopyRec
MOVE.L A1,-(SP) ; save ptr(xdr) in cache buffer
LEA FXVxkrOff(A4),A1 ; dest = key buffer in FXM vars <17Oct85>
MOVEQ #(lenxkr/4)-1,D0 ; loop index in long words <17Oct85>
@1 MOVE.L (A0)+,(A1)+ ; Copy the key record <17Oct85>
DBRA D0,@1 ; <17Oct85>
MOVEA.L (SP)+,A0 ; source = xdr in cache buffer
LEA FXVxdrOff(A4),A1 ; dest = xdr in FXM vars
MOVEQ #(lenxdr/4)-1,D0 ; loop index in long words <17Oct85>
@2 MOVE.L (A0)+,(A1)+ ; Copy the data record <17Oct85>
DBRA D0,@2 ; <17Oct85>
LEA FXVxkrOff(A4),A0 ; A0 = ptr to xkr in FXM vars <17Oct85>
LEA FXVxdrOff(A4),A1 ; A1 = ptr to xdr in FXM vars <17Oct85>
MOVE.W xkrFABN(A0),D3 ; D3 = beg FABN for extent record
; search record for desired extent entry
FSSchRec
MOVE.W D4,D0 ; desired FABN
BSR.S XRSearch ; search record for desired FABN <17Oct85>
BNE.S FSExit1 ; didn't find it ->
; clean up and exit
FSExit
CLR.W D0 ; result = ok
FSExit1
MOVEM.L (A6)+,D4-D6 ; restore regs
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set condition codes
RTS ; exit XFSearch
;_________________________________________________________________________________
;
; Subroutine: XRSearch (Extent Record Search)
;
; Function: Searches extent record for the extent mapping a given file
; allocation block number (FABN).
;
; Input: D0.W - desired FABN
; A1.L - pointer to extent data record (xdr)
; D3.W - beginning FABN for extent record
;
; Output: D0.W - result code
; 0 = ok
; FXRangeErr = desired FABN > last mapped FABN in record
; D1.L - offset to extent entry within xdr
; result = 0, offset to extent mapping desired FABN
; result = FXRangeErr, offset to last extent in record
; D3.W - ending FABN +1
;_________________________________________________________________________________
XRSearch
MOVE.L D2,-(SP) ; save regs
MOVE.W D0,D2 ; D2 = desired FABN
CLR.W D1 ; D1 = initial offset
@1 MOVE.W xdrNumABlks(A1,D1.W),D0 ; number of alloc blks in extent
BEQ.S @2 ; null extent ->
ADD.W D0,D3 ; ending FABN + 1
CMP.W D2,D3 ; desired FAB within this extent?
BHI.S RSExit ; yes, all done ->
ADDQ.W #lenExt,D1 ; bump to next extent
CMPI.W #maxExtOff,D1 ; past last extent?
BLE.S @1 ; no, continue search ->
@2 SUBQ.W #lenExt,D1 ; back up to previous extent
BGE.S @3 ; still within the record ->
CLR.W D1 ; reset to 1st extent
@3 MOVEQ #FXRangeErr,D0 ; result = 'range error' <02Oct85>
BRA.S RSExit1 ; exit ->
RSExit
CLR.W D0 ; result = ok
RSExit1
MOVE.L (SP)+,D2 ; restore regs
TST.W D0 ; set condition codes
RTS ; exit XRSearch
;_________________________________________________________________________________
;
; Subroutine: XRUpdate (Extent Record Update)
;
; Function: Updates the current extent record. For the FCB resident record,
; the FCB is marked 'dirty'. For an extents file record, the
; corresponding BTree record is re-located and updated.
;
; Input: A2.L - VCB pointer
; A3.L - FCB pointer
; A4.L - pointer to FXM vars
; A0.L - pointer to extent key record (xkr)
; 0 = FCB resident extent record
; A1.L - pointer to extent data record(xdr)
; D2.L - BTree hint for extent record
;
; Output: D0.W - result code
; 0 = ok
; other = error
; D2.L - updated BTree hint for extent record <17Oct85>
;_________________________________________________________________________________
XRUpdate
MOVE.L (SP)+,-(A6) ; save return address on A6 stack
MOVEM.L D1/A0-A1,-(A6) ; save registers <17Oct85>
MOVE.L A0,D0 ; FCB resident record?
BNE.S RUUpdFile ; no, must update extents file ->
BSET #FCBModBit,FCBMdRByt(A3) ; mark FCB dirty
BRA.S RUExit ; all done, exit ->
RUUpdFile
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
JSR BTSearch ; re-locate the extent file record
BNE.S RUExit1 ; error ->
LEA FXVxdrOff(A4),A0 ; source = xdr in FXM vars
MOVEQ #(lenxdr/4)-1,D0 ; loop index in long words <17Oct85>
@2 MOVE.L (A0)+,(A1)+ ; update the xdr in cache buffer <17Oct85>
DBRA D0,@2 ; <17Oct85>
MOVE.W VCBXTRef(A2),D0 ; extents file refnum
JSR BTUpdate ; update BTree record
BNE.S RUExit1 ; error ->
RUExit
CLR.W D0 ; result = 'ok'
RUExit1
MOVEM.L (A6)+,D1/A0-A1 ; restore registers <17Oct85>
MOVE.L (A6)+,-(SP) ; put return address back on stack
TST.W D0 ; set condition codes
RTS ; exit XRUpdate
END
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