ST-Computer Leser-CD 1999 January/STC_CD_01_1999.iso/base/pd_ph105/read_me.txt

Text File | 2000-01-08 | 15KB | 337 lines

This patch is supposed to bring the Pure Debugger to modern times.
The problem is, that (AFAIK) ASH is not allowed, for license reasons,
to make an update by themselves. Therefore somebody else had to do it
without the source code. Since I like using PD I did it.

Problems of PD I know of, theire conditions of occurrence, and theire
status (S = solved, N = not solved, U= understood but still unsolved):

NR.    SNU occurence         Explanation
1    U    Multitasking    Sometimes at leaving PD the left Mousebutton seams
                        pressed

2    S    MagiC            PC can't start PD as singletask

3    S    MagiC...        PD does not closes open files on 'Program reset'
                        -> on restart Fopen produces an error

4    S    always            PD does not uses XBRA

5    S    always            PD redirects vectors but does not test if a program,
                        jumping over these vectors is PD or anybody else ->
                        for example if a program, running parallel to PD
                        finishes  (Pterm) PD assumes, that this means,
                        that the program to debug has finished.

6    U    Graphiccard        changing screen per Setscreen does not work

7    S    always            On running the first program, PD prints an ESC H -> if
                        a console window (Gemini,...) is open, the Cursor goes
                        to the upper left corner.

8    S    multitasking    sometimes the wrong Menu is visible

9    S    MINT            PD does not work at all, I was tolled

10    S    2 monitors         this is not solving an error, but adding a new feature:
                        you can now run    PD on 2 monitors

11    S    ?                   Sometimes the mouse cursor disappears

12    S    multitasking    PD sometimes try to get memory at the top end, this routine sometimes
                        fails under multitasking OS and always under MagiC. Normely this has
                        no direct effect, since PD reserves mamory at a random position in this
                        case.

13    S    ?                For some time the one monitorversion, including the unpatched PD halted
                        when it tried to change the screen by Setscreen. Since changing the method
                        in the option menu did not helped an other patch become nessessery

14    S    >Gemdos0.19        PD memorizes all Malloc actions to be able to free this memory in program
                        reset. But it ignores Mxalloc

General
*******

To add new routines, some addresses in PD have to be known. This addresses
are stored in PD_ADDR.DAT. On the first run Patch tries to find this adresses
and stores them for future use. But this is not foolproof:
- The searched routines have changed (different PD version than mine)-> wrong
    or no address found
- Somewhere else something has changed, so that by chance it looks
    like the routine -> it seams to be found twice.
If none or more then one occurrences are found, an error message is
issued. Since not all addresses are needed for every patch, you can
still try. If a needed adress is unknown the patch will stop.
For easier control, there will be a textversion of pd_addr.dat written:
pd_addr.txt

How does it works
*****************

a) Run PATCH.PRG and answer the following questions:
    a) One or two-monitor-version?: what ever you want. see 10)
    b) May Setscreen be used? (will only be asked if patching a 1-monitor PD.
        Ja=Yes; Nein=No
        First try using Setscreen. Only if this produces a crash then make an
        other patch and answer with no (Nein) see 13)
    c)    When putting out ESC H ?: s. 7)
        'nie'=never;1. Run; 'jedes Run'=every run
b) if you wish to run the new PDs out of PC: copy the PD.PRG into the
    PC-directory. Therefore you have to rename the original PD.PRG
c) test it

If you want to change something in the patch yourself please set the
options in PC as follow:
Compiler: -C, -P
Assembler: -S
Linker -G, -L, -F, Stacksize 100000
usualy I also have -Y set in all 3 categories, but this is not mendatory.
Now I also set this options in the PRJ-File, so setting them explicitly in
PC is probably not nececerry anymore.
If for whatever reasens you are using an other Compiler but PC, don't expect
to have no problems.

The different problems and their solutions
******************************************

1) left mouse-button pressed
----------------------------
Since menus, windows and the like are not drawn by AES in PD, but
are drawn directly by VDI on the screen, they are kind of invisible
to mouse clicks. The only reason there are not more problems is
because PD runs in supervisor mode, but at the end of the programm
problems occure. I tried solving this problem using
wind_update(BEG_MOUSCTRL) but received some strange effects.

2) Running PD as single task (MagiC)
------------------------------------
To be able to run PD out of PC in single task I wrote a starter (START_PD).
It starts PD by sending a message (AV-Protocol) to the shell. If this shell
understands AV it should find out, if PD has to be run in single task and if
so start it in single task. There has been a problem with the desktop EASE,
it did not gave PD the comandline. If you press the ALTERNATE button while
starting START_PD it will ask some questions:
singeltask or multitask
1 or 2 monitors (PD_1.PRG or PD_2.PRG)

To make it clear, telling the starter to start PD as singeltask only works, if
the AV-Server does it.

3) open files
-------------
If at the end of the program (the one to be debugged) or on a break
there are still files open, the will still be open on a new run. Some
OS like MagiC realise, that this file is tried to be opened for a
second time and exit an error. My solution is to log the calls of
Fcreate, Fopen and Fdelete. On 'program reset' these files are closed
automaticly. Until now only handles between 6 and 63 are observed. If
this should not be enough, change p_flags in PDX, and all routines
using it. But the worst case possible is that PD reacts for files with
handle >63 as it used to with any handle.

4) XBRA
-------

I introduced a XBRA structure for all routines changed by Setexc.
The ID is 'PDeb' for PD_1 and 'PDEB' for PD_2.
The XBRA-Impementation is complet now, meening, that also deinstalling
is done by XBRA. But since PD is to be used with unfinished software,
this is not always possible. So if the deinstalling routine does
not find it's own ID, it will reset the vector to the original state.
The reasen for using 2 ID's is, to be able to debug PD_1 with PD_2.

5) identification of caller
---------------------------

PD does not test who is jumping over changed vectors. In single task
this is fine, but not in multitasking. One very 'nice' error occurs,
when you end a program running parallel to PD. PD exits the message
'program terminated' and exits the run modus. But the program which
was debugged is still runnig, even after finishing PD! Don't ask me
what this can couse for problems (who ownes the memmory,...). Before
finding out I always pressed reset. Now PD saves the adress of it
Basepage at the beginning. Everytime a changed vector (XBRA) is used,
it is tested if it's PD or not. Either the original routine is used or
the PD one. This patch needs 4) and is needed for 3).
For every rule there is an exeption. PD uses the hardcopy Interrupt as a break.
(<ALT><HELP>) If this would be only active while PD is executetd, this would
mean that you have to press <ALT><HELP> for some time. Since this routine only
sets a flag, there is no problem of letting it being active even if a other
programm is executed. This flag is tested during the vertical Blanc routine.
Meaning, that the <ALT><HELP> is memorized at all time, but that PD only reacts
if there is a vb during the time PD is executed. So if PD does not react try
pressing a button, moving a Window of the programm debugged,...

6) Setscreen
------------

PD reserves ST-RAM for a 2nd and 3rd screen, then it trys out if Setscreen
is working. Setscreen would work on some graphic-cards (NOVA,...) if their
RAM and not ST-RAM would be used. So i tried to fake the malloc, but
without success. The problem seems to be, that NOVA-RAM starts at
0xFEC00000 which is negative... . As a partial solution TT-Ram is used
in case a graphic card is reccognized. By now only NOVA cards are
recognized by:
    if (get_cookie('IMNE',(long *)&icb))
        X_pd.p_bs_m=3;
for other graphic cards, the if-condition can either be changed to recognize
other cards by adding '||...' or if the card is always used by deleting the
if totaly. X_pd.p_bs_m includes the Mxalloc modus. It is usualy 0, but will
be changed here to 3. This patch is only included in the one-monitor-patch.

7) ESC H
--------

On the first RUN PD prints ESC H, if a console window(Gemini,...)
is open, the cursor goes to the upper left corner. If this is
wanted or not can be chosen by everybody self. I introduced 3
possibilities:
a) never printing ESC H
b) only at the first RUN (as in the original)
c) at every RUN

8) Menu title
-------------

In multitasking environments sometimes the wrong Menu is visible,
even if the right one is active. I did not found all circumstances
under which it occurs. Therefor I only added an automatic redraw of
the menu shortly after the start of the program, and for all other
cases I added an manual possibility. Just click in the menu line
(y<18) and the menu is redrawn. Of course this should be done in
the right unused part of the menu. This is only included in the
one-monitor-solution, since this problem does not exist with 2 monitors.

9) MINT
-------

I don't know. I never installed MINT, I am not actually interested
in it. But Thomas Künneth and Chris Felsch wrote a starter which
makes it possible to run PD under MiNT. I included this starter in my own
( see 2) ) and so it should be possible to use PD under MiNT now.

10) two monitors
----------------

This was the reason I started writing this patch in the first place.
With this version it is possible to use 2 monitors, similar to the
very good program, SYSMON. It is quite difficult to redirect AES-output,
even more to a different resolution. But luckily this is not necessary,
since PD only uses VDI-calls. Therefore it is only necessary to open
a OFF-Screen Bitmap and return PD that handle instead to the one
expected of v_opnvwk. Besides the mouse curser has to be drawn by PD
it selve. But all this problems are solved under some conditions:
- VDI which supports OFF-screen bitmaps, either per v_opnvwk2 (NOVA-VDI)
    or by v_opnbm (NVDI, NOVA and others if the EdDI-cookie is present
    with version >=1.1)
-ATARI-compatible monitor and second monitor by graphic card is present.

Problems could occur, if a second program, uses two monitors too,
but the only othe program doing so I know off, SYSMON works together with
my one just fine.

There had been Problems with the programm BLACKSCR.PRG, which sets all colors
of the 2nd monitor to black. This has only an effect in the monochrome mode
on TTs. Thatfore if it is a TT I now set the colors to black/white.

Now I use a PC with MagiC PC. Since there I only have one monitor, I can
actualy not use this feature myselv anymore

11) disappearing mouse cursor
-----------------------------

As I never observed this error by my self, or at least don't remember
observing it, which probably is mainly caused by the fact, that I
almost always use PD with 2 monitors, I only introduced a symptomatic
solution. If the cursor disappears, just press the right mouse button
and it should reappear. This is until now untested, but I am optimistic.
If somebody manages to produce a reproducible state in which this error
occurs, then please let me know, and I may find a better solution.

12) Malloc for high memory
--------------------------

While trying to further improve my XBRA implementation (s. 4)) I analysed
a routine and realized, that it had 2 errors. PD sometimes try to get
memory at the top end. That fore it first reserves all memory (in a loop
containing Malloc(-1)) this fails if a other programm reserves memory in the
meantime. This could be solved by changing the break - condition. Then PD
looks for the highest so reserved block and trys to split it so, that tho top
part gets the needed size. This does not funktions under MagiC, since there 32
extra Bytes are reserved with any Malloc. For examble if the Block has 3000 Byte
and PD needs 1000, PD shrinks (Mshrink) the Block to 2000 and trys to reserve 1000
But under MagiC there are only 1968 Bytes left. To be on the safe side I now always
shrink to 64 Bytes less then required under TOS -> I spoil 64 Bytes under TOS, 32
under MagiC. But maybe some other OS needs more. Of course I could calculate the
exact length needed, but to save a few byte this is not sensible, certanly not if
the produced code would be longer than the saved memory

13) Setscreen for 1 monitor
---------------------------
This patch is optional and should only be used if PD otherwise does not run.
I just exchanged the original Setscreen by an empty function:
{}
this works because PD checks after using Setscreen if it was sucsessful, and if not
uses an other way of changing the screen

14 Mxalloc
----------

Since I already introduced my own Fopen, Fcreate and Fclose I decided to include a
complete Version of the Gemdos Dispatcher into the Patch. This also includes Mxalloc,
where as with Malloc in the original PD all memoryallocation is memorized

15) other changes
-----------------

as said in 9) I will try to solve other problems with PD anybody tells
me off. It has a good reason, that I include the source code. So anybody
can include patches by himself, this is needed either when I am not
reachable or if it's a problem I don't have on my configuration. But I
recommend, that every change/addition is brought to my attention. I
then will include it in a new public version. This definitely includes
the case, that GET_ADDR does not finds an address by itself but you
find it by yourself.


Fairware
--------

This program is Fairware, it may be copied freely, but if somebody
needs to get rid of some mo-
ney...

Thanks to
---------

Bernhard Held volunteered as ₧-tester.

Thomas Künneth and Chris Felsch for their MiNT-starter

Wilfried Behne for his help in searching an error (in my patch)
in connection with NVDI.

!!!!!!!!!!!!!!!
!  Attention  !
!!!!!!!!!!!!!!!

On no circumstance PD, either the original or a patched version may
be exchanged without the prior approval of ASH. This program may only
be used to patch officially bought versions of the Pure Debugger. This
is especially true, since some routines (xbra_exc and xbra_Gd_trm)
included in the source code are variations of the original PD code.
These are specially marked.
Exeption, I will give a patched version to ASH. Probably they will put
it in their BOX, so that it is accessible to registered users. But since
there are some options on patching PD, this is only 2nd best to patching it
by yourself.

Author
------

Dimitri Junker
E-Mail:                     [e-mail]
or for long mails (>16k):    [e-mail]