Zap Disassemble

Wrong.

Double wrong. ;-) You provide a way to get a memory dump. How is this different to just passing the address of the error block to *Memory and reading it out of that?

As Colin said, I was rather surprised that Reporter doesn’t have a method of dealing with error blocks directly – like “here’s a pointer, do something smart with it”…

which you can pick up in BASIC and just do ptr%?0 = 13…

As long as your application has provided the buffer, of course. ;-)

More fully, Basalt deals with these cases this way:

string$=RETURN$(pointer%)

Terminate at the first control character.

string$=RETURN$(pointer%,end%)

Terminate at address end% if greater than &8000, or at end% characters.

The statement RETURN$ pointer% [,end%] substitutes a CR, as you suggest.

like “here’s a pointer, do something smart with it”…

I will add that on my ToDo list.
But all this is rather off the original point of this thread!

As I seem to be chasing bugs in other editors lately (see here and here) here’s my fix for HidePtr. The original code has a problem with bytev_callothers as Rick already noticed.

The problem is not in bytev_callothers itself but rather in bytev_done after it returns. Here the code tries to restore the psr flags from r12 but it’s unlikely that r12 has been preserved as it’s used to pass the workspace pointer to each claimant (see OS_Claim).

If the value in r12 is such that bit 28 is set then we’ll return to the OS with V set, with r0 possibly being seen as an invalid error pointer.

; bytev interception
bytev   FNJSR     ; I'm fairly sure that some OS_Bytes take
        MRS     R12,CPSR   ; flags as inputs
        TEQ     R0,#&6A    ; select pointer shape
        BNE     bytev_done

        AND     R2,R1,#&7F   ; mask shape number
        CMP     R2,#4
        LDRHI   R1,mouse_shape_old  ; invalid
        BHI     bytev_done

        LDR     R2,mouse_shape_old
        PUSH    "R2"
        AND     R2,R1,#&FF
        TST     R1,#1<<31
        STREQ   R2,mouse_shape_old
        STREQ   R2,mouse_shape
        BIC     R1,R1,#1<<31
        MVN     R2,#0
        STR     R2,ptr_state
        MOV     R2,R14
        BL      bytev_callothers
        PULL    "R1"

bytev_done
        MSR     CPSR_f,R12
        FNRTS

; call other bytev claimants
; E r2 = previous routines  r12 = flags
bytev_callothers
        STMFD   R13!,{R14}
        MSR     CPSR_f,R12
        MOV     PC,R2

To fix the problem I’ve changed the bytev code to the following. Where we restore ‘our’ flags before calling other claimants and let them sort out ‘their’ flags.

; bytev interception
bytev   FNJSR          ; I'm fairly sure that some OS_Bytes take
        MRS     R12,CPSR   ; flags as inputs
        TEQ     R0,#&6A    ; select pointer shape
        BNE     bytev_done

        AND     R2,R1,#&7F   ; mask shape number
        CMP     R2,#4
        LDRHI   R1,mouse_shape_old  ; invalid
        BHI     bytev_done

        LDR     R2,mouse_shape_old
        STR     R2,[R13,#-4]!
        AND     R2,R1,#&FF
        TST     R1,#1<<31
        STREQ   R2,mouse_shape_old
        STREQ   R2,mouse_shape
        BIC     R1,R1,#1<<31
        MVN     R2,#0
        STR     R2,ptr_state

; call other bytev claimants
; E r2 = previous routines  r12 = flags
bytev_callothers
        MOV     R2,R14
        MSR     CPSR_f,R12
        ADR     R14,bytev_return
        STR     R14,[R13,#-4]!
        MOV     PC,R2

bytev_return
        LDR     R1,[R13],#4
        FNRTS

bytev_done
        MSR     CPSR_f,R12
        FNRTS

With this change HidePtr seems to be okay but it’s hard to be sure. As Rick says: It starts off okay, then gets a bit weird, than goes all out crazy-gonzo.