#! /bin/sh
# Debian Policy §10.4 says /bin/sh has a superset of POSIX functionality
# shellcheck disable=SC3043

set -e



clean_up_giomodule_cache ()
{
    local multiarch="x86_64-linux-gnu"
    local modules="/usr/lib/${multiarch}/gio/modules"
    local iter

    if ! [ -d "$modules" ]; then
        return 0
    fi

    # Don't remove giomodule.cache if libglib2.0-0t64 has been replaced
    # by some other ABI variant of essentially the same library
    # (for example libglib2.0-0xyz), if that ever happens, to
    # avoid causing an equivalent of <https://bugs.debian.org/1065022>.
    #
    # This implementation is based on the assumption that any GLib
    # version that still uses ${libdir}/gio/modules/giomodule.cache
    # will also continue to ship ${libdir}/glib-2.0.
    if [ -d "/usr/lib/${multiarch}/glib-2.0" ]; then
        return 0
    fi

    # As an additional safety-catch, don't remove giomodule.cache if
    # there is at least one module that should have been listed in it.
    for iter in "$modules"/*.so; do
        if [ -e "$iter" ]; then
            echo "$0: not removing $modules/giomodule.cache because $iter still exists" >&2
            return 0
        fi
    done

    rm -f "$modules/giomodule.cache"
    rmdir -p --ignore-fail-on-non-empty "$modules"
}

clean_up_gsettings_schemas ()
{
    local schemas="/usr/share/glib-2.0/schemas"
    local iter

    if ! [ -d "$schemas" ]; then
        return 0
    fi

    # Similarly, instead of using $DPKG_MAINTSCRIPT_PACKAGE_REFCOUNT, only
    # remove gschemas.compiled if GLib has completely gone away - not just
    # libglib2.0-0 and libglib2.0-0t64, but any possible future ABI variant
    # like libglib2.0-0xyz.
    #
    # This implementation is based on the assumption that any GLib
    # version that still uses ${datadir}/glib-2.0/schemas
    # will also continue to ship ${libdir}/glib-2.0.
    for iter in /usr/lib/*/glib-2.0; do
        if [ -e "$iter" ]; then
            return 0
        fi
    done

    # As an additional safety-catch, don't remove gschemas.compiled if
    # there is at least one schema that should have been listed in it.
    for iter in "$schemas"/*.xml; do
        if [ -e "$iter" ]; then
            echo "$0: not removing $schemas/gschemas.compiled because $iter still exists" >&2
            return 0
        fi
    done

    rm -f "$schemas/gschemas.compiled"
    rmdir -p --ignore-fail-on-non-empty "$schemas"
}

case "$1" in
    (purge)
        clean_up_giomodule_cache
        clean_up_gsettings_schemas
        ;;
esac

# vim:set sw=4 sts=4 et: