* Stack.Asm * * Written 1/1/87 by C.Heath * * This program may be freely distributed, provided it is not modified * in any way. If an executable is distributed, use assem and blink 6.7, * which should result in an executable of 400 bytes. * This module replaces the ADOS "Stack" command. It exactly matches * the Stack command syntax except it also will print a reasonable error * message if you use a non-numeric command line. It also will save * a disk block, and should run faster because it is smaller than the * magic 488 byte "icon" file size, and is a single segment instead of two. * This is installment two of the "Abolish ADOS Commands" series. * Collect them all, amaze your friends. ****** Equates and publics *************************************** INCLUDE "exec/types.i" INCLUDE "libraries/dos.i" INCLUDE "libraries/dosextens.i" MIN_LIB set $1f ; Library minimum rev level! ASC_ZERO set $30 ; Ascii ZERO MIN_STACK set 1600 ; Minimum stack allowed by the ; ADOS "stack" command my_str set -60 ; Size of string allowed to build *** NOTE: If you use Manx's assembler V3.30E, substitute "public" for "xref" xlib macro xref _LVO\1 endm xlib OpenLibrary xlib CloseLibrary xlib FindTask xlib Output xlib Write ****** The Program *************************************** * NOTE: If you are using Manx's assembler V3.30E, you should uncomment * the following three lines: * entry .begin * public .begin *.begin Start: move.l A0,A2 ; Register A2 is cmdline henceforth move.l 4,a6 ; ExecBase suba.l A1,A1 jsr _LVOFindTask(A6) move.l D0,A3 ; Process base move.l pr_CLI(A3),D0 beq.s BadExit ; Not a CLI process. Punt asl.l #2,D0 move.l D0,A3 ; A3 points at CLIStruct henceforth lea DOSName(pc),A1 ; Open DOS.library moveq.l #MIN_LIB,d0 jsr _LVOOpenLibrary(A6) or.l D0,D0 beq.s BadExit ; Can't!! Return error value... move.l D0,A6 ; DOSBase in A6 henceforth link A5,#my_str ; Need some writeable space in stack ************************************************************************ * * Check the input arguements * If there is no arg, print the old stack value * Else If the arg is a valid number input, set new stack * Else print error message * ************************************************************************ move.b (A2),D0 beq.s Do_OldStack cmp.b #$0a,D0 beq.s Do_OldStack ; No command line, print old stack * * Here, loop to get input for new stack * Loop getting Ascii digits * moveq.l #0,D0 ; New Stack Value built into D0 ll0: moveq.l #0,D1 move.b (A2)+,D1 cmp.b #$0A,D1 beq.s eos sub.b #'0',D1 blt.s bad_input ; Test for valid digits cmp.b #9,D1 bgt.s bad_input add.l D0,D0 move.l D0,D2 ; Multiply prior value by 10 asl.l #2,D2 ; Required to allow long_word value add.l D2,D0 add.l D1,D0 ; Add in new digit bra.s ll0 ; Loop on digits * End of string, register D0 is new stack value in bytes eos: cmp.l #MIN_STACK,D0 blt.s too_small ; Match "stack" command lsr.l #2,D0 ; Convert to LWords move.l D0,cli_DefaultStack(A3) ; Save it and bra.s finished ; Get Outa Here! * Bad input string. Print error message bad_input: lea bad_str(pc),A0 bra.s ok_print * Input value too small. Must match ADOS's requirements, ick. too_small: lea str_too_small(pc),A0 bra.s ok_print ************************************************************************ * * BadExit is where to go if there is an error opening the DOS library * This should only happen if things are really sick * ************************************************************************ BadExit: moveq #20,D0 rts * No input value, print out the current default stack setting instead Do_OldStack: move.l cli_DefaultStack(A3),D0 asl.l #2,D0 ; Get current size lea SStr(pc),A1 ; Copy the string to stack area lea my_str(A5),A0 llz: move.b (A1)+,(A0)+ bne.s llz subq #1,A0 ; Build string HERE lea divtab(pc),A1 ; Sucessive subtraction table here ll1: move.l (A1)+,D1 cmp.l D1,D0 blt.s ll1 ; Find first digit ll2: moveq #ASC_ZERO,D2 ; Loop to calculate this digit ll3: cmp.l D1,D0 blt.s ll4 addq #1,D2 sub.l D1,D0 bra.s ll3 ll4: move.b D2,(A0)+ ; Output this digit move.l (A1)+,D1 ; Continue to next until bne.s ll2 ; There Ain't No More outahere: lea ZStr(pc),A1 ; Copy the "bytes" too ll5: move.b (a1)+,(A0)+ bne.s ll5 lea my_str(A5),A0 ; Get string origin *************************************************************************** * * Here, Write the string at A0, which is null terminated. * *************************************************************************** ok_print: move.l A0,D2 ; Set pointer in D2 for Write arg moveq.l #-1,D3 llx: addq.l #1,D3 ; Get length in D3 tst.b (A0)+ bne.s llx jsr _LVOOutput(A6) ; Get Output handle move.l D0,D1 ; It's a calling arg jsr _LVOWrite(A6) ; Echo "String" finished: move.l A6,A1 move.l 4,A6 ; AbsExecBase jsr _LVOCloseLibrary(A6) moveq #0,D0 ; Exit(0) unlk A5 rts *************************************************************************** * * Following is just constant data used by the prgram * *************************************************************************** divtab: dc.l 10000000,1000000,100000,10000,1000,100,10,1,0 DOSName: dc.b 'dos.library',0 str_too_small: dc.b 'suggested stack size too small',$0a,0 bad_str: dc.b 'Bad command line. Use "stack #"',$0a,0 SStr: dc.b 'current stack size is ',0 ZStr: dc.b ' bytes',$0a,0 END