; Filter non-text bytes from pipe stream. INCLUDE "/include/init.i" ; Local Equs ; FilTex uses a buffer split into two 1000 byte parts, the first for writing, ; the last part for reading. Reads/Writes are HalfBufSize bytes large max. DefaultThreshold EQU 4 BufSize EQU 2000 ; Keep this one < 32K HalfBufSize EQU BufSize/2 ; Variable storage STRUCT ArgArray,(4+1)*4 LONG InputHandle LONG StdOutput WORD Threshold SIZE ; Regs WriteBufIndex EQUR D4 ReadBufIndex EQUR D5 ReadBytesLeft EQUR D6 LatestByte EQUR D7 BufferPtr EQUR A2 FilterTablePtr EQUR A3 ErrorStrPtr EQUR A4 ; Start STACK 4000 INIT ; Let ARP interpret the commandline MOVE.L ComLineBase(GP),A0 MOVE.L ComLineSize(GP),D0 LEA HelpMsg(PC),A1 LEA ArgArray(GP),A2 LEA Template(PC),A3 MOVE.L A1,(A2) CALL GADS MOVE.L (A2),ErrorStrPtr TST.L D0 BEQ ErrorExit BMI ErrorExit ; Fetch & check the threshold value. LEA BadThreshold(PC),ErrorStrPtr MOVE.W #DefaultThreshold,Threshold(GP) MOVE.L ArgArray+4(GP),A0 MOVE.L A0,D0 BEQ.S UseDefault CALL Atol BEQ ErrorExit CMP.L #HalfBufSize,D0 BHI ErrorExit MOVE.W D0,Threshold(GP) BEQ ErrorExit UseDefault: ; Check if the source is STDIN, if so open that. MOVE.L ArgArray(GP),A0 LEA StdinID(PC),A1 CALL Strcmp BNE.S NoStdin CALL Input MOVE.L D0,InputHandle(GP) BRA.S InFileOpened NoStdin: ; Else open a normal source file (Tracked) LEA SourceOpenError(PC),ErrorStrPtr MOVE.L ArgArray(GP),D1 MOVE.L #MODE_OLDFILE,D2 CALL ArpOpen MOVE.L D0,InputHandle(GP) BEQ ErrorExit InFileOpened: ; Fetch the StdOutput CALL Output MOVE.L D0,StdOutput(GP) ; Alloc tracked mem for the read/write buffer. LEA OutOfMem(PC),ErrorStrPtr MOVE.L #BufSize+1,D0 ; add 1 to allow for LF termination MOVEQ #0,D1 CALL ArpAllocMem TST.L D0 BEQ ErrorExit MOVE.L D0,BufferPtr ; Initialize for the filtered copy loop LEA FilterTableBase(PC),FilterTablePtr MOVEQ #0,WriteBufIndex ; Read next chunk of bytes. DoNextRead: LEA ReadError(PC),ErrorStrPtr MOVEQ #0,ReadBufIndex MOVE.W #HalfBufSize,ReadBufIndex MOVE.L InputHandle(GP),D1 MOVE.L BufferPtr,D2 ADD.L ReadBufIndex,D2 MOVE.L ReadBufIndex,D3 CALL Read MOVE.W D0,ReadBytesLeft BMI ErrorExit BEQ.S TryToWriteWriteBuffer ; Find text bytes. CheckForTextBytes: MOVEQ #0,LatestByte MOVE.B 0(BufferPtr,ReadBufIndex.W),LatestByte ADDQ.W #1,ReadBufIndex SUBQ.W #1,ReadBytesLeft TST.B 0(FilterTablePtr,LatestByte.W) BEQ.S TryToWriteWriteBuffer ; Process text bytes MOVE.B LatestByte,0(BufferPtr,WriteBufIndex.W) ADDQ.W #1,WriteBufIndex CMP.W #HalfBufSize,WriteBufIndex BNE.S CheckReadBufStatus ; Check if the number of bytes to write equals or exceeds the threshold TryToWriteWriteBuffer: CMP.W Threshold(GP),WriteBufIndex BLO.S NeLeWritezPas ; Check if string is null-terminated (if requested to do so) TST.L ArgArray+12(GP) ; Check NULT switch BEQ.S NoNullCheck TST.B LatestByte BNE.S NeLeWritezPas NoNullCheck: ; Terminate write with a linefeed if needed & not prohibited CMP.B #10,-1(BufferPtr,WriteBufIndex.W) BEQ.S DoTheWrite TST.L ArgArray+8(GP) ; Check NOLF switch BNE.S DoTheWrite MOVE.B #10,0(BufferPtr,WriteBufIndex.W) ADDQ.W #1,WriteBufIndex ; The actual write to the StdOutput DoTheWrite: LEA WriteError(PC),ErrorStrPtr MOVE.L StdOutput(GP),D1 MOVE.L BufferPtr,D2 MOVE.W WriteBufIndex,D3 EXT.L D3 CALL Write CMP.L D0,D3 BNE.S ErrorExit ; Check if user hit ^C SUB.L A1,A1 CALL CheckAbort MOVE.L A1,ErrorStrPtr TST.L D0 BNE.S ErrorExit NeLeWritezPas: ; Reset the write buffer index. MOVEQ #0,WriteBufIndex ; Check if no more read bytes left, if so read, exit if last read had zero length ; (An adjective, verb and a noun. YOU try 'n make a natural language interpreter!) CheckReadBufStatus: TST.W ReadBytesLeft BNE CheckForTextBytes CMP.W #HalfBufSize,ReadBufIndex BNE DoNextRead ; Done, cleanup Exit: CLR.W ReturnCode(GP) SUB.L ErrorStrPtr,ErrorStrPtr ErrorExit: ; Display error string, if any, and exit MOVE.L ErrorStrPtr,D0 BEQ.S NoErrorMsg MOVE.L D0,A1 CALL Puts NoErrorMsg: RTS ; The string section Template: DC.B 'File/a,THRESH/k,NOLF/s,NULT/s',0 HelpMsg: DC.B 'FilTex - filter out non-text.',10 DC.B 'Usage: FilTex [THRESH #] [NOLF] [NULT]',0 StdinID: DC.B 'STDIN',0 BadThreshold: DC.B 'Illegal threshold value',0 SourceOpenError: DC.B 'Could not open source file',0 OutOfMem: DC.B 'Out of memory!',0 ReadError: DC.B 'Error while reading',0 WriteError: DC.B 'Error while writing',0 CNOP 0,4 ; This is the filtering array DC.B 'TextTab:' FilterTableBase: ; 0 1 2 3 4 5 6 7 8 9 A B C D E F DC.B 000,000,000,000,000,000,000,000,000,$09,$0A,000,000,000,000,000 ;0 DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;1 DC.B ' ','!','"','#','$','%','&',$27,'(',')','*','+',',','-','.','/' ;2 DC.B '0','1','2','3','4','5','6','7','8','9',':',';','<','=','>','?' ;3 DC.B 000,'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O' ;4 DC.B 'P','Q','R','S','T','U','V','W','X','Y','Z','[','\',']','^','_' ;5 DC.B 000,'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o' ;6 DC.B 'p','q','r','s','t','u','v','w','x','y','z','{','|','}','~',000 ;7 DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;8 DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;9 DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;A DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;B DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;C DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;D DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;E DC.B 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 ;F ; 0 1 2 3 4 5 6 7 8 9 A B C D E F END