Bugzilla Bug 111062

Annoyed by the fact http://bugs.gentoo.org/show_bug.cgi?id=82000 is not 
solved on ppc or ~ppc I added 
sci-mathematics/maxima ~x86 in my /etc/portage/package.keywords
and emerged maxima-5.9.1-r5. 
I can now start xmaxima without problems (5.9.1 complains about not
finding the documentation and exit immediately).
The problem is that when I quit xmaxima my xserver is shutdown as well
and I am back to the kdm logging screen. 

Reproducible: Always
Steps to Reproduce:
1.Add sci-mathematics/maxima ~x86 to /etc/portage/package.keywords
2.emerge maxima with the following use flags: +auctex +clisp (-cmucl) -emacs
-gcl +tetex 
3.start xmaxima
4. quit xmaxima

Actual Results:  
My Xserver died.

Expected Results:  
quitted gracefully without taking my Xsession away with it.

merge info
Portage 2.0.51.22-r3 (default-linux/ppc/2005.0, gcc-3.4.4, glibc-2.3.5-r2,
2.6.12-gentoo-r6 ppc)
=================================================================
System uname: 2.6.12-gentoo-r6 ppc 7450, altivec supported
Gentoo Base System version 1.6.13
ccache version 2.3 [enabled]
dev-lang/python:     2.3.5-r2, 2.4.2
sys-apps/sandbox:    1.2.12
sys-devel/autoconf:  2.13, 2.59-r6
sys-devel/automake:  1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r1
sys-devel/binutils:  2.16.1
sys-devel/libtool:   1.5.18-r1
virtual/os-headers:  2.6.11-r2
ACCEPT_KEYWORDS="ppc"
AUTOCLEAN="yes"
CBUILD="powerpc-unknown-linux-gnu"
CFLAGS="-O2 -mcpu=7450 -pipe -maltivec -mabi=altivec -mpowerpc-gfxopt
-fsigned-char -frename-registers -fweb -fno-strict-aliasing"
CHOST="powerpc-unknown-linux-gnu"
CONFIG_PROTECT="/etc /usr/kde/2/share/config /usr/kde/3.4/env
/usr/kde/3.4/share/config /usr/kde/3.4/shutdown /usr/kde/3/share/config
/usr/lib/X11/xkb /usr/share/config /usr/share/texmf/dvipdfm/config/
/usr/share/texmf/dvips/config/ /usr/share/texmf/tex/generic/config/
/usr/share/texmf/tex/platex/config/ /usr/share/texmf/xdvi/ /var/qmail/control"
CONFIG_PROTECT_MASK="/etc/gconf /etc/splash /etc/terminfo /etc/env.d"
CXXFLAGS="-O2 -mcpu=7450 -pipe -maltivec -mabi=altivec -mpowerpc-gfxopt
-fsigned-char -frename-registers -fweb -fno-strict-aliasing"
DISTDIR="/usr/portage/distfiles"
FEATURES="autoconfig ccache distlocks fixpackages sandbox sfperms strict"
GENTOO_MIRRORS="ftp://ftp.vic.keypoint.com.au http://mirrors.tds.net/gentoo
ftp://mirrors.tds.net/gentoo http://mirror.tucdemonic.org/gentoo/"
PKGDIR="/usr/portage/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
SYNC="rsync://rsync.au.gentoo.org/gentoo-portage"
USE="ppc X a52 aac aalib alsa altivec arts berkdb bitmap-fonts cairo cddb cdf
cdparanoia cdr crypt cups curl dts dv dvd dvdr dvdread emboss encode esd f77 fam
fbcon ffmpeg flac foomaticdb fortran gd gdbm ggi gif gpm graphviz gstreamer gtk
gtk2 hal ieee1394 imagemagick imlib imlib2 ipv6 java jbig jpeg jpeg2k kde
kdexdeltas lcms libwww live lzo mad mikmod mjpeg motif mp3 mpeg ncurses netcdf
network nls nptl ogg oggvorbis openexr opengl oss pam pdflib perl plotutils png
ppds python qt rdesktop readline samba sdl slang slp spell ssl szip tcltk tcpd
tetex theora tiff truetype truetype-fonts type1-fonts udev unicode vorbis wmf
xine xml xml2 xmms xv xvid zeroconf zlib userland_GNU kernel_linux elibc_glibc"
Unset:  ASFLAGS, CTARGET, LANG, LC_ALL, LDFLAGS, LINGUAS, MAKEOPTS, PORTDIR_OVERLAY

Actually after applying the symlink fix from Bug 82000 I have
the same problem with xmaxima 5.9.1. I cannot find any log of 
what is wrong. I remember trying maxima some time ago probably
5.9.0 and it didn't have these problems. 

Has the ppc keyword been dropped accidentally? Couldn't find anythin in the
ChangeLog...

I have the same problem on AMD64 using clisp (instead of the default gcl) as a
backend. I didn't test with gcl.

Yes, xmaxima doesn't take the X session down on exiting if gcl is used as the
backend (AMD64)

I tried the gcl backend on ppc and on my system at least xmaxima
effectively doesn't take X down. The problem is that maxima segfault
on the comand line which means that all I have is an empty xmaxima 
window with no prompt.

I tracked down the clisp crash problem, and have a couple of patches to fix it.

1. maxima has clisp-specific code to get pid, which is broken for recent
versions of clisp with maxima-5.9.1 -- it instead returns instead '-1'

2. the maxima CMkill function checks only that pid is an int -- it accepts '-1'
as a valid pid

Put the two together, and you have the reported problem -- SIGTERM sent to
every process, and killing everything the user running maxima has permissions
to kill. 

The first issue has been fixed since maxima-5.9.2
(http://cvs.sourceforge.net/viewcvs.py/maxima/maxima/src/server.lisp?rev=1.11&view=log)

This is enough to prevent xmaxima from going trigger-happy in this case, but I
like to be conservative and added a second patch that makes CMkill refuse to
kill pid <= 1.

Created an attachment (id=84107) [edit]
fix getpid function to work with modern versions of clisp

Created an attachment (id=84108) [edit]
maxima CMkill function checks for pid > 1 

Created an attachment (id=84109) [edit]
updated maxima ebuild that applies the above patches

Patches committed after nerdboy from sci team tried and approved. I left the
ebuild rev at r5 so that x86 maxima users happily using gcl or cmucl won't have
to rebuild unnecessarily.