wdm on alpha (and perhaps other 64 bit environments?)

Altivo

I wanted a lightweight, simple display manager to allow me to log in remotely using another PC or X-terminal, and wdm looked like the best choice. Most of the more widely used managers (kdm, gdm, lightdm, entrance) are masked in Portage (at least on the alpha,) and xdm has a lot of dependencies and one of those is blocked. So I merged wdm, which brought in WindowMaker (wmaker) with it. The latter works fine, but isn't really my cup of tea I think. I'm using fluxbox at the moment. Unfortunately, wdm will not start successfully.

I've been over the wdm-config, Xresources and Xsetup_0 repeatedly. They seem to match what is expected.

When launched from the command line by root, There are two attempts to paint the screen on vt7, each ending in a flash and going to black. Then the display returns to vt1 where root is logged in, showing this:

Obviously that's the geometry for a window, presumably the login prompt. The window offsets are absurd, though. Except, if you had a -1 value in a 64 bit register but interpreted only the low order 32 bits, isn't that the number you'd get? I don't imagine it is possible to open a window with that geometry, which would explain the failure. The wdm process remains running, the vt7 screen remains blank, and I have to use CTRL-C to close down wdm.

Here is what comes up in /var/log/xdm-errors.log:

http://wiki.x.org

The "Cannot open config file" line makes no sense. The file is there, readable by all. So I tried passing the file on the command line with "-config /etc/X11/wdm/wdm-config" but the results look just the same.

So two questions arise here at least. Where does wdm really think its configuration file should be? And why is it misinterpreting the window offset position when it uses the built-in default?

And the bigger question: Has anyone managed to use wdm on a 64-bit processor? I suspect this looks the same on all of them, or at least on the little endian ones.

My next step, I suppose, is to try to read the source code, but I'm not well-versed in C so I thought I'd ask just in case someone already knows.
_________________
Have patience with me, I'm only half-baked.
--Altivo

Altivo · Posted: Fri Aug 21, 2015 11:30 am Post subject:

After digging through the wdm source code, I concluded that the "default" path for the wdm-config is actually /usr/lib/X11/wdm/wdm-config so I copied the wdm directory from /etc/X11 to /usr/lib/X11 but this changed nothing. Same symptoms, same error log entries.

Comments from other threads seem to indicate that wdm works on i386, so it appears that this is an alpha specific issue (or possibly 32 bit vs 64 bit processor issue.)

Does anyone know of a display manager that actually works on alpha? I haven't tried xdm yet, but looking at the dependencies I suspect it will also have issues.
_________________
Have patience with me, I'm only half-baked.
--Altivo

Altivo · Posted: Sat Aug 22, 2015 2:28 pm Post subject:

Further examination reveals that the default directory thing really is part of the problem. The compiled code looks in /usr/lib/X11/wdm for its configuration files, but the Portage installation created those files in /etc/X11/wdm instead. Adding a soft link from the former to the latter does solve some of the problem. It also appears that, since wdm is intended as an xdm replacement, tihe default wdm configuration files make reference to some xdm configuration files which may or may not exist on the local machine. That would depend on whether xdm had ever been configured there. I didn't have those files.

The present state of affairs still remains puzzling.

I can now get a login screen from wdm on two of three remote terminals that I've tried. One is a somewhat out of date Ubuntu (10.04 LTS) installation on a Pentium 4 Dell, which can log in, and get a WindowMaker desktop at least. Everything appears to be functional from there. Another is an Asus netbook running Linux Mint Maya, which can also log in successfully at least with WindowMaker. So far, selecting fluxbox from the session pull down on either machine does NOT work for some reason, though fluxbox works at the alpha console when launched by startx.

The third machine is a Raspberry Pi 2 model B running Raspbian (Debian) which fails to get the login screen up. The connection succeeds because the cursor arrow changes shape briefly before the black screen closes and you are returned to the screen from which X was invoked. The X error output shows no errors, even when set to audit level 4. It just shows four unnamed applications being opened and then closed in reverse sequence before X exits successfully. I thought at first that this was because the Raspberry Pi has the modern wide screen display while the Dell has the old conventional 3:2 aspect ratio. However, that isn't the case because the Asus netbook is a wide screen (though tiny) and comes up at 1024x700 with no difficulty.

It may be that the Raspberry Pi has some permission or authorization issues, and I will look into that. The Pi does, however, succeed in getting a full screen login to the alpha when the latter is running OpenVMS or OpenBSD.

I've always found remote X connectivity to be finicky to set up. With wdm on Gentoo, however, there are definitely issues with both the documentation and the default configurations.

[This post was made from Dillo, running on Gentoo Alpha over a remote connection from Linux Mint. The functionality is fine when it is running.]

And if it seems that I'm talking to myself, yes, that is the case. No advice or suggestions have been coming here or on the IRC channels, but I'm recording what I find in case it will be of use to someone in the future. This even though I may well be the first person in many months (or years) to actually install Gentoo on an Alpha from scratch. I'd love to find out that I'm wrong about that, but I see no evidence to the contrary.
_________________
Have patience with me, I'm only half-baked.
--Altivo

Altivo · Posted: Sun Aug 23, 2015 3:17 pm Post subject:

Confirmed: wdm can consistently manage a login and start a WindowMaker session on at least some remote X servers. The one X server on which it fails does work with every other X client system I have, including those that run on the Alpha (OpenVMS, OpenBSD, Debian 4.0) as well as on i386 (Ubuntu, Linux Mint.) Unfortunately, wdm remains unable to start a session on the local console, for reasons that are unclear to me.

Also confirmed: wdm cannot initiate a fluxbox session, though no error is logged. It just blinks and returns to the login greeter. Once a WindowMaker session is started, however, it is possible to convert it to a fluxbox session by using the "restart as fluxbox" choice in the WindowMaker root menu. Then fluxbox works normally.

This all seems pretty erratic and bizarre to me. :-(

.
_________________
Have patience with me, I'm only half-baked.
--Altivo

lost+found · Posted: Sun Aug 23, 2015 5:14 pm Post subject:

Hi,

I use wdm on x86 and amd64 (both Gentoo). From my memory, it worked pretty much out of the box, but I'm not starting wdm from the command line. The default procedure on Gentoo seems to be adding xdm to default runlevel (or starting /etc/init.d/xdm manually), and add DISPLAYMANAGER="wdm" to /etc/conf.d/xdm.

Hold on, I'll try to look up the changes I've made to the config files (also to improve security, and font rendering)...

lost+found · Edit 24/8/2015:

Some quick notes... What's needed depends on the situation ofc. Maybe I'll find some more things I did for wdm.

...

/etc/X11/wdm/Xsession (toolbar in xterm):

Altivo · Posted: Mon Aug 24, 2015 1:55 am Post subject:

Thanks for the tips. Some of those things I had already done, others I didn't even know to look at. I should be able to adjust things and retry tomorrow.

As for starting wdm from the command line, the man page does say you can do that. Primarily for debugging, I'm sure, but that's what I'm still doing.
_________________
Have patience with me, I'm only half-baked.
--Altivo

lost+found · Posted: Mon Aug 24, 2015 8:21 am Post subject:

More random notes. Most probably also known. WDM really deserves a wiki...

Altivo · Posted: Mon Aug 24, 2015 2:05 pm Post subject:

Thanks again. You've at least solved one problem for me: I didn't realize that I needed to add scripting to get fluxbox started. I had added it in wdm-config but not in Xclients. All the other familiar window managers are in there, but fluxbox was omitted. After adding an option for fluxbox, wdm is able to start a fluxbox session just as it already could do WindowMaker.

The big puzzle is still why wdm can't start up on the local vt7. It tries, and fails. So far I've not been able to get any debug or error information on why this failure happens. You can see it start to paint the background, then there's a flash and it flips back to the last text console session that was used. And it isn't because the local X server can't run. With startx or xinit a session can be opened there and runs normally. But getting wdm to place a login panel there to begin a session has so far failed every time.

I did have wdm inserted into /etc/conf.d/xdm and it is possible to start wdm with

lost+found · Posted: Mon Aug 24, 2015 3:05 pm Post subject:

Just a guess... wdm has a default $HOME directory path compiled in: /var/run/wdm. Does this directory really exist? I think it's installed once, but since a few years /var/run has become a symlink to /run (tmpfs!), and the contents won't survive a reboot. That's the reason I recompiled wdm with the `--with-fakehome=/var/lib/wdm' configure option (for fontconfig files).

Edit: removed 'Never tried the greeter. ' I confused it with the Chooser.

Altivo · Posted: Mon Aug 24, 2015 5:51 pm Post subject:

As a quick test of that, I created /var/lib/wdm and made a soft link from /var/run/wdm to it. Restarted xdm (really wdm) and still the same results. Two attempts and a black screen.

/var/log/xdm-errors.log has this:

I've been resisting the urge to fix that misspelling "guarenteed" because there clearly are worse issues here. ;-p
_________________
Have patience with me, I'm only half-baked.
--Altivo

lost+found · Posted: Mon Aug 24, 2015 6:58 pm Post subject:

Too bad wdm is unmaintained upstream. I hope it's not bit rotting away. The project development has been handed over, but after that no new release followed. The last dev still seems interested in Window Maker development though. On Github he made some changes related to the greeter, but I can't read C unfortunately.

Altivo · Posted: Mon Aug 24, 2015 8:11 pm Post subject:

I can read it a little, but not well enough to mess with someone else's code. It's often said that C is a "write only" or a "write once, read never" language and I'm inclined to agree.

In this particular case, I'm more inclined to suspect that my configuration is somehow incomplete, since wdm works in about half the test conditions I've tried. The lack of clear diagnostics I'd lay at the feet of Xorg, since they and XFree86 before them have always been horribly obtuse about telling you what went wrong.

Maybe a better release will come along. At least startx does work at the console, and I have only one remote machine where I'd really like to get in through wdm but it's shut out. The other remotes all work.

The odd machine out is a Raspberry Pi, and I've noticed that remote nodes often think it is a Macintosh, which may have some bearing on the problem. Or not.
_________________
Have patience with me, I'm only half-baked.
--Altivo