Developer CD Series 1993 March: Other People's Memory

home *** CD-ROM | disk | FTP | other *** search

/ Developer CD Series 1993…ch: Other People's Memory / ADC Developer CD (1993-03) (''Other People's Memory'')_iso / Dev.CD Mar 93.iso / Tools & Apps / Networking & Communications / Network Watch (DMZ) 1.0 / dmz.a next >

Wrap

Text File | 1992-08-17 | 20.7 KB | 593 lines | [TEXT/MPS ]

;_________________________________________________________________________ ; ; dmz.a ;_________________________________________________________________________ ; ; DTS Code Sample ; ; ©1990 Apple Computer, Inc. ; ; 3/7/90 - 10/26/90 pvh ; ;_________________________________________________________________________ PRINT PUSH,OFF ; don't print any of this stuff INCLUDE 'QuickEqu.a' INCLUDE 'ToolEqu.a' INCLUDE 'SysEqu.a' INCLUDE 'Traps.a' INCLUDE 'ATalkEqu.a' INCLUDE 'SysErr.a' PRINT POP ; restore the PRINT options ;--------------------------------------- mySaveA5 PROC EXPORT movea.l (a7)+, a1 ; save the return address MOVE.L a5, -(a7) ; move current a5 onto stack movea.l $2C(a0), a5 ; get 'our' a5 from saved paramBlock jmp (a1) ; return to sender ENDP ;--------------------------------------- myRestoreA5 PROC EXPORT movea.l (a7)+, a1 ; save the return address MOVE.L (a7)+, a5 ; move saved a5 back into a5 jmp (a1) ; return to sender ENDP ;--------------------------------------- RestoreA5 PROC EXPORT MOVE.L (a7)+, a5 ; move saved a5 back into a5 ENDP ; Socket Listener Sample ; ; 3/92 Jim Luther, Apple DTS ; ; ©1992 Apple Computer, Inc. ;_________________________________________________________________________ INCLUDE 'QuickEqu.a' INCLUDE 'ToolEqu.a' INCLUDE 'SysEqu.a' INCLUDE 'Traps.a' INCLUDE 'ATalkEqu.a' INCLUDE 'SysErr.a' ; ; ; Record Types ; ;_________________________________________________________________________ QHdr RECORD 0 qFlags DS.W 1 qHead DS.L 1 qTail DS.L 1 ENDR PacketBuffer RECORD 0 qLink DS.L 1 qType DS.W 1 buffer_Type DS.W 1 ; DDP Type buffer_NodeID DS.W 1 ; Destination node buffer_Address DS.L 1 ; Source address in AddrBlock format buffer_Hops DS.W 1 ; Hop count buffer_ActCount DS.W 1 ; length of DDP datagram buffer_CheckSum DS.W 1 ; Chksum error returned here (cksumErr or noErr) buffer_Ticks DS.W 1 ; TickCount when handler called buffer_Data DS.B ddpMaxData ; the DDP datagram ENDR ;_________________________________________________________________________ ; ; Local Variables ; ;_________________________________________________________________________ SL_Locals PROC ENTRY free_queue,used_queue,current_qelem free_queue DC.L 0 ; pointer to freeQ QHdr - initialized by InitSktListener used_queue DC.L 0 ; pointer to usedQ QHdr - initialized by InitSktListener current_qelem DC.L 0 ; pointer to current PacketBuffer record ; initialized by InitSktListener, then ; set by socket listener after every packet. ; NIL if no buffer is available. ENDP ;_________________________________________________________________________ ; ; SL_DoChksum - accumulate ongoing checksum (from Inside Macintosh) ; ; Input: ; D1 (word) = number of bytes to checksum ; D3 (word) = current checksum ; A1 points to the bytes to checksum ; ; Return: ; D0 is modified ; D3 (word) = accumulated checksum ;_________________________________________________________________________ SL_DoChksum PROC CLR.W D0 ; Clear high byte SUBQ.W #1,D1 ; Decrement count for DBRA ChksumLoop: MOVE.B (A1)+,D0 ; read a byte into D0 ADD.W D0,D3 ; accumulate checksum ROL.W #1,D3 ; rotate left one bit DBRA D1,ChksumLoop ; loop if more bytes RTS ENDP ;_________________________________________________________________________ ; ; SL_TheListener ; ;_________________________________________________________________________ ;_________________________________________________________________________ ; ; SL_TheListner - process packets received at the designated socket ; ; Input: ; D0 (byte) = packet's destination socket number ; D1 (word) = number of bytes left to read in packet ; A0 points to the bytes to checksum ; A1 points to the bytes to checksum ; A2 points to MPP's local variables ; A3 points to next free byte in Read Header Area ; A4 points to ReadPacket and ReadRest jump table ; ; Return: ; D0 is modified ; D3 (word) = accumulated checksum ;_________________________________________________________________________ SL_TheListener PROC EXPORT WITH PacketBuffer ; get pointer to current PacketBuffer GetBuffer: LEA current_qelem,A3 ; get the pointer to the PacketBuffer to use MOVE.L (A3),A3 MOVE.L A3,D0 ; if no PacketBuffer BEQ.S NoBuffer ; then ignore packet ; read rest of packet into PacketBuffer.datagramData MOVE.L D1,D3 ; read rest of packet LEA buffer_data(A3),A3 ; A3 = ^bufferData JSR 2(A4) ; ReadRest BEQ.S ProcessPacket ; If no error, continue BRA RcvRTS ; there was an error, so ignore packet ; No buffer; ignore the packet NoBuffer CLR D3 ; Set to ignore packet (buffer size = 0) JSR 2(A4) ; ReadRest BRA GetNextBuffer ; We missed this packet, but maybe there ; will be a buffer for the next packet… ; Process the packet you just read in. ; ReadRest has been called so registers A0-A3 and D0-D3 are free to use. ; We'll use registers this way: PktBuff EQU A0 ; the current PacketBuffer MPPLocals EQU A2 ; pointer to MPP's local variables (still set up ; from entry to socket listener) HopCount EQU D0 ; used to get the hop count DatagramLength EQU D1 ; used to determine the datagram length SourceNetAddr EQU D2 ; used to build the source network address ProcessPacket: LEA current_qelem,PktBuff ; PktBuff = current_qelem MOVE.L (PktBuff),PktBuff ; do everything that's common to both long and short DDP headers ; save tickCount in buffer_Ticks field MOVE.L Ticks,buffer_Ticks(PktBuff) ; first, clear buffer_Type and buffer_NodeID to ensure their high bytes are 0 CLR.W buffer_Type(PktBuff) ; clear buffer_Type CLR.W buffer_NodeID(PktBuff) ; clear buffer_NodeID ; clear SourceNetAddr to prepare to build network address MOVEQ #0,SourceNetAddr ; build the network address in SourceNetAddr ; get the hop count MOVE.W toRHA+lapHdSz+ddpLength(MPPLocals),HopCount ; Get hop/length field ANDI.W #DDPHopsMask,HopCount ; Mask off the hop count bits LSR.W #2,HopCount ; shift hop count into low bits of high byte LSR.W #8,HopCount ; shift hop count into low byte MOVE.W HopCount,buffer_Hops(PktBuff) ; and move it into the PacketBuffer ; get the packet length (including the DDP header) MOVE.W toRHA+lapHdSz+ddpLength(MPPLocals),DatagramLength ; Get length field ANDI.W #ddpLenMask,DatagramLength ; Mask off the hop count bits ; now, find out if the DDP header is long or short MOVE.B toRHA+lapType(MPPLocals),D3 ; Get LAP type CMPI.B #shortDDP,D3 ; is this a long or short DDP header? BEQ.S IsShortHdr ; skip if short DDP header ; it's a long DDP header MOVE.B toRHA+lapHdSz+ddpType(MPPLocals),buffer_Type+1(PktBuff) ; get DDP type MOVE.B toRHA+lapHdSz+ddpDstNode(MPPLocals),buffer_NodeID+1(PktBuff) ; get destination node from LAP header MOVE.L toRHA+lapHdSz+ddpSrcNet(MPPLocals),SourceNetAddr ; source network in hi word ; source node in lo byte LSL.W #8,SourceNetAddr ; shift source node up to high byte of low word ; get source socket from DDP header MOVE.B toRHA+lapHdSz+ddpSrcSkt(MPPLocals),SourceNetAddr SUB.W #ddpType+1,DatagramLength ; DatagramLength = number of bytes in datagram BRA.S MoveToBuffer ; checksum time… TST.W toRHA+lapHdSz+ddpChecksum(MPPLocals) ;Does packet have checksum? BEQ.S noChecksum ; Calculate checksum over DDP header MOVE.L DatagramLength,-(SP) ; save DatagramLength (D1) CLR D3 ; set checksum to zero MOVEQ #ddphSzLong-ddpDstNet,D1 ; D1 = length of header part to checksum ; pointer to dest network number in DDP header LEA toRHA+lapHdSz+ddpDstNet(MPPLocals),A1 JSR SL_DoChksum ; checksum of DDP header part ; (D3 holds accumulated checksum) ; Calculate checksum over data portion (if any) MOVE.L buffer_Data(PktBuff),A1 ; pointer to datagram MOVE.L (SP)+,DatagramLength ; restore DatagramLength (D1) MOVE.L DatagramLength,-(SP) ; save DatagramLength (D1) ; before calling SL_DoChksum BEQ.S TestChecksum ; don't checksum datagram if its length = 0 JSR SL_DoChksum ; checksum of DDP datagram part ; (D3 holds accumulated checksum) TestChecksum: MOVE.L (SP)+,DatagramLength ; restore DatagramLength (D1) ; Now make sure the checksum is OK. TST.W D3 ; is the calculated value zero? BNE.S NotZero ; no -- go and use it SUBQ.W #1,D3 ; it is 0; make it -1 NotZero: CMP.W toRHA+lapHdSz+ddpChecksum(MPPLocals),D3 BNE.S ChecksumErr ; Bad checksum MOVE.W #0,buffer_CheckSum(A0) ; no errors BRA.S noChecksum ChecksumErr: MOVE.W #ckSumErr,buffer_CheckSum(PktBuff) ; checksum error noChecksum: BRA.S MoveToBuffer ; it's a short DDP header IsShortHdr: MOVE.B toRHA+lapHdSz+sddpType(MPPLocals),buffer_Type+1(PktBuff) ; get DDP type MOVE.B toRHA+lapDstAdr(MPPLocals),buffer_NodeID+1(PktBuff) ; get destination node from LAP header MOVE.B toRHA+lapSrcAdr(MPPLocals),SourceNetAddr ; get source node from LAP header LSL.W #8,SourceNetAddr ; shift src node up to high byte of low word MOVE.B toRHA+lapHdSz+sddpSrcSkt(MPPLocals),SourceNetAddr ; get source socket from short DDP header SUB.W #sddpType+1,DatagramLength ; DatagramLength = number of bytes in datagram MoveToBuffer: MOVE.L SourceNetAddr,buffer_Address(PktBuff) ;move source network address into PacketBuffer MOVE.W DatagramLength,buffer_ActCount(PktBuff) ; move datagram length into PacketBuffer ; Now that we're done with the PacketBuffer, enqueue it into the usedQ and get ; another buffer from the freeQ for the next packet. LEA used_queue,A1 ; A1 = ^used_queue MOVE.L (A1),A1 ; A1 = used_queue (pointer to usedQ) _Enqueue ; put the PacketBuffer in the usedQ GetNextBuffer: LEA free_queue,A1 ; A1 = ^free_queue MOVE.L (A1),A1 ; A1 = free_queue (pointer to freeQ) LEA current_qelem, A0 ; copy freeQ.qHead into current_qelem MOVE.L qHead(A1),(A0) MOVEA.L qHead(A1),A0 ; A0 = freeQ.qHead _Dequeue RcvRTS: RTS ; return to caller ENDP ;_________________________________________________________________________ ; Function SL_InitSktListener(freeQ, usedQ: QHdrPtr): OSErr ; ; SL_InitSktListener PROC EXPORT StackFrame RECORD {A6Link},DECR ; build a stack frame record Result1 DS.W 1 ; function's result returned to caller ParamBegin EQU * ; start parameters after this point freeQ DS.L 1 ; freeQ parameter usedQ DS.L 1 ; usedQ parameter ParamSize EQU ParamBegin-* ; size of all the passed parameters RetAddr DS.L 1 ; placeholder for return address A6Link DS.L 1 ; placeholder for A6 link LocalSize EQU * ; size of all the local variables ENDR WITH StackFrame,QHdr ; use these record types LINK A6,#LocalSize ; allocate our local stack frame ; copy the queue header pointers into our local storage for use in the listener LEA used_queue,A0 ; copy usedQ into used_queue MOVE.L usedQ(A6),(A0) LEA free_queue,A0 ; copy freeQ into free_queue MOVE.L freeQ(A6),(A0) ; dequeue the first buffer record from freeQ and set current_qelem to it MOVEA.L freeQ(A6),A1 ; A1 = ^freeQ LEA current_qelem, A0 ; copy freeQ.qHead into current_qelem MOVE.L qHead(A1),(A0) MOVEA.L qHead(A1),A0 ; A0 = freeQ.qHead _Dequeue MOVE.W D0,Result1(A6) ; Return status @1 UNLK A6 ; destroy the link MOVEA.L (SP)+,A0 ; pull off the return address ADDA.L #ParamSize,SP ; strip all of the caller's parameters JMP (A0) ; return to the caller ENDP ;-------------------------------------- ; myVBLSpinInstall ; ; 10/90 pvh ; ; I hated the ToolLib spinning cursor routines enough to make up my own. Those routines ; are fine if you base your spinning cursor off a tight loop where you can continuously call the ; routines to actually spin the cursor. In my case that library was not ideal, so instead ; I just threw ('slapped' might be the better term) together a VBL task that spins the cursor ; instead (ala MacApp). ; ; This routine & the clean up routine that follows are pretty mcuh self explanatory. 4 cursors ; are preloaded & locked so they'll be sure to be available when the VBL task is called. The ; task is set up and moved into the application's heap. The task itself checks a locally saved ; variable for the cursor ID, loads in that cursor and sets that cursor as the current one if ; the cursor state is not currently busy (by checking CrsrBusy). ; ; When the task finishes, global references to the VBL task are used in the clean up routine ; (stopAndRemoveSpinningCursor) to remove the task & associated buffers. The cursors are also ; released from memory here. ; ; 10/16/90 pvh ; ; gMac was imported originally to help support color cursors within this task, but that endeavor ; was turning out to be too much of a hack (even for me), so it's staying around as a remanant of ; that failed attempt just to mark another one of my failures. :-) spinGlobals RECORD 0 ; this is our global data storage gtheTaskPtr DS.L 1 ; pointer to hold task itself gtheVBLPtr DS.L 1 ; pointer for VBL task record ENDR EXPORT (sg):DATA sg DS spinGlobals ; globals for spin cursor myVBLSpinInstall PROC EXPORT IMPORT gMac : DATA StackFrame RECORD {A6Link},DECR ; build a stack frame record ParamBegin EQU * ; start listing parameters here ParamSize EQU ParamBegin-* ; size of all the passed parameters RetAddr DS.L 1 ; place holder for return address A6Link DS.L 1 ; place holder for A6 link taskSize DS.L 1 ; size of our VBL task curses DS.L 4 ; handle for our cursor cursType DS.L 1 LocalSize EQU * ; size of all the local variables ENDR WITH StackFrame, SysEnvRec ; cover our local stack frame LINK A6,#LocalSize ; allocate our local stack frame ; pre-load in the resources to make sure they are around CLR.L -(sp) ; make space on the stack for result MOVE.L #'CURS', cursType(a6) ; another remanant from color stuff (don't ask) MOVE.L cursType(a6), -(sp) MOVE #1001, -(sp) _GetResource MOVE.L (sp)+, curses(a6) MOVE.L curses(a6), a0 _HLock CLR.L -(sp) ; make space on the stack for result MOVE.L cursType(a6), -(sp) MOVE #1002, -(sp) _GetResource MOVE.L (sp)+, curses+4(a6) MOVE.L curses+4(a6), a0 _HLock CLR.L -(sp) ; make space on the stack for result MOVE.L cursType(a6), -(sp) MOVE #1003, -(sp) _GetResource MOVE.L (sp)+, curses+8(a6) MOVE.L curses+8(a6), a0 _HLock CLR.L -(sp) ; make space on the stack for result MOVE.L cursType(a6), -(sp) MOVE #1004, -(sp) _GetResource MOVE.L (sp)+, curses+12(a6) MOVE.L curses+12(a6), a0 _HLock BRA.S theTaskEnd ; actual VBL Task theTaskBegin MOVEM.L a0-a6/d0-d7, -(sp) ; save BRA.S afterStorage A5Storage DC.L 0 afterStorage ; reset the vbl count MOVE.W #5, vblCount(a0) ; restore A5 for globals we may have LEA A5Storage, a0 MOVE.L (a0), a5 BRA.S xxx cursorStorage DC.W $03E9 ; storage for cursor type, start with first cursor ID xxx LEA cursorStorage, a0 ADD.W #1, (a0) MOVE.W (a0), d0 CMP.W #1005, d0 BLT.S doCursor MOVE.W #1001, (a0) ; start over with cursor type #1001 MOVE.W #1001, d0 ; it needs to be in d0 doCursor CLR.L -(a7) ; make some space for return MOVE.W d0, -(a7) ; move in cursor type _GetCursor MOVE.L (a7)+, a0 ; move handle into a0 BEQ.S vblExit ; test for nil handle tst.b CrsrBusy ; cursor drawing as we speak? then split. BNE.S vblExit MOVE.L (a0), -(a7) ; deref and push on stack _SetCursor vblExit MOVEM.L (sp)+, a0-a6/d0-d7 ; restore rts theTaskEnd ; VBL initialization code LEA theTaskEnd, a0 ; address of tail of task LEA theTaskBegin, a1 ; head of task MOVE.L a0, d0 ; get size of task SUB.L a1, d0 MOVE.L d0, taskSize(a6) LEA A5Storage, a0 ; put current A5 into our storage area in code MOVE.L CurrentA5, (a0) ; set up VBL record MOVE.L #vblPhase+2, d0 ; size of VBLTask _NewPtr MOVE.L a0, sg.gtheVBLPtr(a5) ; setup block of memory to hold task itself (in our heap, not the System heap) MOVE.L taskSize(a6), d0 _NewPtr MOVE.L a0, sg.gtheTaskPtr(a5) ; move the task code into block in heap LEA theTaskBegin, a0 ; head of task MOVE.L sg.gTheTaskPtr(a5), a1 MOVE.L taskSize(a6), d0 _BlockMove MOVE.L sg.gtheTaskPtr(a5), a1 MOVE.L sg.gtheVBLPtr(a5), a0 MOVE.L a1, vblAddr(a0) ; a1 contains address of moved TheTask MOVE.W #vType, qType(a0) MOVE.W #10, vblCount(a0) MOVE.W #4, vblPhase(a0) ; whatever _VInstall Exit UNLK A6 ; destroy the link MOVEA.L (SP)+,A0 ; pull off the return address ADDA.L #ParamSize,SP ; strip all of the caller's parameters JMP (A0) ; return to the caller ENDP ;-------------------------------------- ; this routine disposes of the VBL spinning cursor task & removes memory allocated for the ; task. also unloads the cursors from the heap. stopAndRemoveSpinningCursor PROC EXPORT IMPORT gtheTaskPtr : DATA IMPORT gtheVBLPtr : DATA MOVE.L sg.gtheVBLPtr, a0 _VRemove MOVE.L sg.gtheVBLPtr, a0 _DisposPtr MOVE.L sg.gtheTaskPtr, a0 _DisposPtr ; unload the cursors CLR.L -(sp) MOVE.L #'CURS', -(sp) MOVE #1001, -(sp) _GetResource _ReleaseResource CLR.L -(sp) MOVE.L #'CURS', -(sp) MOVE #1002, -(sp) _GetResource _ReleaseResource CLR.L -(sp) MOVE.L #'CURS', -(sp) MOVE #1003, -(sp) _GetResource _ReleaseResource CLR.L -(sp) MOVE.L #'CURS', -(sp) MOVE #1004, -(sp) _GetResource _ReleaseResource rts ENDP ;-------------------------------------- END ; end of this source file