How to refer to pacman's installation root in pre_install, etc

pocm · 2011-04-06 02:16:29

I have been unable to find any documentation of exactly how to refer to pacman's installation root from inside the .install script functions. Curious, I started looking through /var/abs/core for some real-world examples that might clue me in. What I found surprised me - from the looks of it, many of the functions there simply assume that their working directory IS the pacman installation root. For example:

/var/abs/core/ca-certificates/ca-certificates.install:

post_install() {
   usr/sbin/update-ca-certificates --fresh
}

post_upgrade() {
   usr/sbin/update-ca-certificates --fresh
}

pre_remove() {
   # clean up certificates
   local _backup=$(mktemp)
   mv etc/ca-certificates.conf ${_backup}
   echo > etc/ca-certificates.conf
   usr/sbin/update-ca-certificates --fresh
   mv ${_backup} etc/ca-certificates.conf
}

post_remove() {
   # remove the cert file if it is empty
   [[ -s etc/ssl/certs/ca-certificates.crt ]] || rm -f etc/ssl/certs/ca-certificates.crt
}

And yet, some others seem to assume that the install root is "/", like here:

/var/abs/core/crda/crda.install:

## arg 1:  the new package version
post_install() {
  echo "Uncomment the right regulatory domain in /etc/conf.d/wireless-regdom."
  echo "It will automatically be set when necessary."
}

## arg 1:  the new package version
## arg 2:  the old package version
post_upgrade() {
  # In an upgrade from 1.0.1-1 or older, the wireless-regdom file moves from the crda package
  # to the new wireless-regdb package. If the user changed the file, it is save to overwrite the one
  # from wireless-regdb by the user-defined one
  if [ $(vercmp $2 1.0.1-2) -lt 0 ]; then
    if [ -f /etc/conf.d/wireless-regdom.pacorig -a -n "$(grep -v ^# /etc/conf.d/wireless-regdom.pacorig 2>/dev/null | grep -v ^$)" ]; then
      mv /etc/conf.d/wireless-regdom.pacorig /etc/conf.d/wireless-regdom
    fi
  fi
}

or here:

/var/abs/core/cryptsetup/encrypt_install:

# vim: set ft=sh:

install ()
{
    if [ -z "${CRYPTO_MODULES}" ]; then
        MODULES=" dm-crypt $(all_modules "/crypto/") "
    else
        MODULES=" dm-crypt ${CRYPTO_MODULES} "
    fi
    FILES=""
    SCRIPT="encrypt"
    add_dir "/dev/mapper"
    [ -f "/sbin/cryptsetup" ] && add_binary "/sbin/cryptsetup" "/sbin/cryptsetup"
    [ -f "/usr/sbin/cryptsetup" ] && add_binary "/usr/sbin/cryptsetup" "/sbin/cryptsetup"
    add_binary "/sbin/dmsetup"
    add_file "/lib/udev/rules.d/10-dm.rules"
    add_file "/lib/udev/rules.d/13-dm-disk.rules"
    add_file "/lib/udev/rules.d/95-dm-notify.rules"
}

help ()
{
cat<<HELPEOF
  This hook allows for an encrypted root device.
HELPEOF
}

Since I'd normally take the PKGBUILDs in /core/ as fairly good examples of what the Arch devs consider best practice, it's leaving me with either two conclusions: this is a bug, or I'm missing something. Any input is appreciated. :)

toofishes · 2011-04-06 03:18:56

We chroot() and then chdir() to the root directory in every install script executed- so it is no assumption at all.
http://projects.archlinux.org/pacman.gi … aa3e7#n421

Preference would be to omit the leading /, but due to the chroot/chdir combo, both should work.

b2ag · 2016-09-19 17:18:08

encrypt_install is a mkinitcpio hook install script and has nothing to do with pacman.

WorMzy · 2016-09-19 18:26:32

Why would you register to bump a five year old thread with that comment?

Please don't necrobump.

Closing.

Arch Linux

#1 2011-04-06 02:16:29

How to refer to pacman's installation root in pre_install, etc

#2 2011-04-06 03:18:56

Re: How to refer to pacman's installation root in pre_install, etc

#3 2016-09-19 17:18:08

Re: How to refer to pacman's installation root in pre_install, etc

#4 2016-09-19 18:26:32

Re: How to refer to pacman's installation root in pre_install, etc

Board footer