[lmi] Creating a chroot for cross-building lmi

[Greg Chicares]

Here, between scissors lines, is a quasi-script that successfully
creates a debian-8 chroot and cross-builds lmi for msw there.
Some comments and questions follow the script. I call it only a
"quasi-script" because I've tested it by cutting and pasting each
line or block of lines; interaction is required at several points,
e.g., to enter passwords that I don't want to write in a script.

--------8<--------8<--------8<--------8<--------8<--------8<--------8<--------
# Create a chroot for cross-building lmi--with wine, which is
# required to run programs built in the chroot.

# Starting in a normal terminal, enter a root shell.
su
mkdir -p /srv/chroot/cross3
apt-get update
apt-get install schroot debootstrap

# If the connection hiccups, 'debootstrap' doesn't seem to resume,
# so keep trying until it succeeds.

debootstrap --arch=amd64 jessie /srv/chroot/cross3 
http://httpredir.debian.org/debian
while [ $? -ne 0 ]; do !!; done

cat >/etc/schroot/chroot.d/cross3.conf <<\EOF
[cross3]
description=debian-8 cross build with wine
directory=/srv/chroot/cross3
users=greg
groups=greg
root-groups=root
EOF

# Exit root shell (return to normal shell).
exit

# This command--to start a root shell in the chroot--can be run as a
# normal user. It will prompt for the root password.

schroot --chroot=cross3 --user=root --directory=/
# enter password

# Add i386 before installing wine, so that wine can run 32-bit .exe's .

dpkg --add-architecture i386

apt-get update
apt-get install g++-mingw-w64-i686 automake libtool make pkg-config \
 git zsh bzip2 unzip sudo wine

# Don't worry about messages like these:
#   E: Can not write log (Is /dev/pts mounted?)
#   [FAIL] Can't start system message bus - /proc is not mounted ... failed!
# It's okay that /dev/pts and /proc are not mounted in this chroot.

addgroup --gid=1000 greg
adduser --gid=1000 --uid=1000 greg
# enter user password, twice
# then just press Enter repeatedly to accept defaults

mkdir -p /opt/lmi
chown greg:greg /opt/lmi
mkdir -p /cache_for_lmi
chown greg:greg /cache_for_lmi

chsh -s /bin/zsh greg
touch /home/greg/.zshrc
chown greg:greg /home/greg/.zshrc

# Substitute your system's $DISPLAY below:

cat >/home/greg/.zshrc <<\EOF
export WINEPATH='Z:\\opt\\lmi\\local\\bin;Z:\\opt\\lmi\\local\\lib'
export LMI_HOST=i686-w64-mingw32
export PATH="/opt/lmi/local/bin:/opt/lmi/local/lib:$PATH"
# At a regular user prompt, outside the chroot, do this:
#   $ echo $DISPLAY
# and replace :0.0 below with the string it returns:
export DISPLAY=":0.0"

export coefficiency='--jobs=32'

# export TZ=UCT
# export LANG=en_US.UTF-8 LC_TIME=en_DK.UTF-8 LC_COLLATE=C.UTF-8
#  No--better to do this:
# update-locale LANG=en_US.UTF-8 LC_TIME=en_DK.UTF-8 LC_COLLATE=C.UTF-8

# bindkey "\e[3~" delete-char      # Del
# bindkey '\e[H' beginning-of-line # Home
# bindkey '\e[F' end-of-line       # End
bindkey "^[[1;5D" backward-word  # Ctrl-left
bindkey "^[[1;5C" forward-word   # Ctrl-right
bindkey '\e[1;3D' backward-word  # Alt-left
bindkey '\e[1;3C' forward-word   # Alt-right

prompt='%d[%?]%(!.#.$)'

HISTSIZE=1000
SAVEHIST=1000
HISTFILE=~/.history
setopt HIST_IGNORE_DUPS

autoload -U compinit
compinit -u
EOF

# Repair /usr/share/libtool/config/ltmain.sh as indicated here:
#   http://lists.gnu.org/archive/html/libtool-patches/2011-06/msg00001.html
# Do this as root because root owns the file.

cat >/home/greg/ltmain.sh.patch <<\EOF
--- /usr/share/libtool/config/ltmain.sh.original 2016-01-25 03:43:07.768000000 
+0000
+++ /usr/share/libtool/config/ltmain.sh 2016-01-25 03:44:17.100000000 +0000
@@ -4178,7 +4178,8 @@
 /* declarations of non-ANSI functions */
 #if defined(__MINGW32__)
 # ifdef __STRICT_ANSI__
-int _putenv (const char *);
+     /* int _putenv (const char *); */
+_CRTIMP int _putenv (const char *);
 # endif
 #elif defined(__CYGWIN__)
 # ifdef __STRICT_ANSI__
EOF

patch --dry-run --strip=0 </home/greg/ltmain.sh.patch \
 && patch --strip=0 </home/greg/ltmain.sh.patch

# Exit from the root shell in the chroot.
exit

# If cached lmi downloads are available elsewhere, copy them, e.g.:
#   cp -a /srv/chroot/cross1/cache_for_lmi/* /srv/chroot/cross3/cache_for_lmi/
# This optional step merely conserves bandwidth.

# Enter the chroot as a normal user

schroot --chroot=cross3

wget -N 'http://git.savannah.gnu.org/cgit/lmi.git/plain/install_msw.sh'
chmod +x install_msw.sh
./install_msw.sh >log 2>&1
-------->8-------->8-------->8-------->8-------->8-------->8-------->8--------

I anticipate running this periodically, so I'd much prefer to cache
the 'debootstrap' step. I tried splitting it into these two steps:

  debootstrap --arch=amd64 --download-only jessie /srv/cache 
http://httpredir.debian.org/debian
  debootstrap --arch=amd64 --second-stage 
--second-stage-target=/srv/chroot/cross3 file:///srv/cache

but the '--second-stage' step failed with this message:
  cat: /usr/share/debootstrap/suite: No such file or directory
What am I doing wrong?

And is there a way to cache downloads for this step:
  apt-get update
  apt-get install g++-mingw-w64-i686 automake libtool make pkg-config \
    git zsh bzip2 unzip sudo wine
which I'm doing as root inside the chroot (which runs a later version
of debian than my real system)?

During 'debootstrap', I see messages like this:
#   E: Can not write log (Is /dev/pts mounted?)
#   [FAIL] Can't start system message bus - /proc is not mounted ... failed!
and I just ignore them, because the chroot seems to work perfectly.
What negative consequences could this have?

The '~/.zshrc' created by the quasi-script suggests running
  update-locale LANG=en_US.UTF-8 LC_TIME=en_DK.UTF-8 LC_COLLATE=C.UTF-8
but I haven't installed 'update-locale' in the chroot. This doesn't
seem to matter: time is UTC, and text like
  tn_range.hpp:/// This class's raison d'être is to
prints e-circonflexe correctly. BTW, `locale` shows all LC_* facets set
to "POSIX".

When the last step
  ./install_msw.sh >log 2>&1
finishes, I see a popup messagebox:
  Wine could not find a Mono package...see http://wiki.winehq.org/Mono
I simply hit Cancel, and everything seems fine, and I never see it again.
'install_msw.sh' makes the lmi 'install' target, which does this:
  @cd $(data_dir); $(PERFORM) $(bin_dir)/product_files$(EXEEXT)
where $PERFORM is 'wine'; this is the first time 'wine' is used in the
chroot, and apparently the first time it's run it checks for 'mono'.
This shouldn't matter, because 'mono' is some "dot-net" thing we don't
need. Debian is aware of it:
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=677094
so I guess we should just live with the nuisance for now.