Current File : //usr/share/apache2/apache2-maintscript-helper
# apache2-maintscript-helper - Apache2 helper function for maintainer scripts
# Copyright (C) 2012 Arno Töll <debian@toell.net>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
# the Software, and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
# FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
# COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
# IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
# VARIABLES
#
# global environment variables used by apache2-maintscript-helper:
# * APACHE2_MAINTSCRIPT_DEBUG:
# set this to any non-zero value to get debug output
# * APACHE2_MAINTSCRIPT_HELPER_QUIET:
# set this to any non-zero value to omit any output
# * EXPORT_APACHE2_MAINTSCRIPT_HELPER:
# will be defined by apache2-maintscript-helper
# to avoid inclusion loops. Do not set this
# variable manually
# * APACHE2_NEED_ACTION:
# will be defined if a function call wants to
# override the behavior of apache2_needs_action.
# Do not rely on this variable. It is considered
# an implementation detail.
# * APACHE2_MAINTSCRIPT_NAME
# * APACHE2_MAINTSCRIPT_PACKAGE
# * APACHE2_MAINTSCRIPT_METHOD
# * APACHE2_MAINTSCRIPT_ARGUMENT
# these variables contain information about the
# maintainer script which is calling the
# maintscript-helper. It contains arguments which
# dpkg supplies to maintainer scripts and similar
# information. These variables are an
# implementation detail and not to be changed.
#
# You might want to set them manually only if you
# are calling apache2-maintscript-helper from
# some place which does not preserve the original
# script arguments for example when calling from
# a subfunction instead of the main function in
# your maintainer script
#
# INITIALIZATION
#
if [ -n "${EXPORT_APACHE2_MAINTSCRIPT_HELPER:-}" ] ; then
return
else
EXPORT_APACHE2_MAINTSCRIPT_HELPER=1
if [ -n "${APACHE2_MAINTSCRIPT_DEBUG:-}" ] ; then
set -x
elif [ -e /etc/apache2/envvars ] ; then
APACHE2_MAINTSCRIPT_DEBUG=$(. /etc/apache2/envvars && echo ${APACHE2_MAINTSCRIPT_DEBUG})
if [ -n "${APACHE2_MAINTSCRIPT_DEBUG:-}" ] ; then
set -x
fi
fi
APACHE2_MAINTSCRIPT_DEFER=
if ! dpkg-query -f '${Status}' -W apache2|egrep -q 'installed|triggers-awaited|triggers-pending'; then
echo "Package apache2 is not configured yet. Will defer actions by package $DPKG_MAINTSCRIPT_PACKAGE."
APACHE2_MAINTSCRIPT_DEFER=/var/lib/apache2/deferred_actions
fi
if [ -z "$1" ] ; then
echo "You must invoke apache2-maintscript-helper with an unmodified environment when sourcing it" >&2
return 1
fi
APACHE2_MAINTSCRIPT_NAME="$DPKG_MAINTSCRIPT_NAME"
[ "$APACHE2_MAINTSCRIPT_NAME" ] || APACHE2_MAINTSCRIPT_NAME="${0##*.}"
case "$APACHE2_MAINTSCRIPT_NAME" in
preinst|prerm|postrm|postinst)
# yay - recognized script
;;
*)
echo "apache2-maintscript-helper invoked from an unrecognized maintainer script: exiting" >&2
return 1
;;
esac
APACHE2_MAINTSCRIPT_PACKAGE="$DPKG_MAINTSCRIPT_PACKAGE"
if [ -z "$APACHE2_MAINTSCRIPT_PACKAGE" ]; then
APACHE2_MAINTSCRIPT_PACKAGE="${0##*/}"
APACHE2_MAINTSCRIPT_PACKAGE="${APACHE2_MAINTSCRIPT_PACKAGE%.*}"
fi
if [ -z "$APACHE2_MAINTSCRIPT_METHOD" ] ; then
APACHE2_MAINTSCRIPT_METHOD="$1"
fi
case "$APACHE2_MAINTSCRIPT_METHOD" in
install|upgrade|abort-upgrade|configure|deconfigure|abort-remove|abort-remove|abort-deconfigure|remove|failed-upgrade|purge|disappear|abort-install|triggered)
# yay - recognized script
;;
*)
echo "apache2-maintscript-helper invoked from a modified environment. Please hint required arguments manually" >&2
return 1
;;
esac
if [ -z "$APACHE2_MAINTSCRIPT_ARGUMENT" ] ; then
APACHE2_MAINTSCRIPT_ARGUMENT="${2:-}"
fi
fi
#
# FUNCTIONS
#
#
# Function apache2_msg
# print out a warning to both, the syslog and a local standard output.
# This function should generally be used to display messages related to
# the web server in maintainer scripts.
# Parameters:
# priority
# The message priority. Recognized values are the same as defined
# by syslog(3), thus: one among debug, info, notice, warning,
# err, crit, alert, emerg.
# If no known priority is recognized, the priority is set to
# "warning".
# message
# The message as a string. It is printed out verbatim.
# Behavior:
# No message is displayed if APACHE2_MAINTSCRIPT_HELPER_QUIET is defined
# Returns:
# this function always returns 0
# Since: 2.4.1-3
apache2_msg()
{
local PRIORITY="$1"
local MSG="$2"
[ -z "$APACHE2_MAINTSCRIPT_HELPER_QUIET" ] && echo "$MSG" >&2
[ -x /usr/bin/logger ] || return 0
case "$PRIORITY" in
debug|info|notice|warning|err|crit|alert|emerg)
;;
*)
PRIORITY="warning"
;;
esac
local LOGGER="/usr/bin/logger -p daemon.$PRIORITY -t $APACHE2_MAINTSCRIPT_PACKAGE "
$LOGGER "$MSG" || return 0
}
#
# Function apache2_needs_action
# succeeds if the package invoking the maintscript helper
# needs any work. This function can be used as a conditional whether a
# certain function should be executed by means of the package state.
# Note, calling some other functions may change the outcome of this
# function, depending on the action required
#Parameters:
# none
# Returns:
# 0 if an older version of the maintainer script invoking the helper is
# already installed
# 1 otherwise
# Since: 2.4.1-3
apache2_needs_action()
{
# Summary how the maintscript behaves:
# preinst:
# Not sure why anyone would like to call this function in preinst. Die loud.
# prerm remove:
# Basically the same as postrm. If a maintainer would like to
# disable his module before removing his stuff, be it.
# However, we have nothing useful to do if we're called in any
# other way than "remove" in prerm.
# postinst configure
# Probably the most important invokation. When invoked in configure we:
# - enable the piece of configuration on fresh installs
# - do nothing on upgrades UNLESS the configuration was removed automatically in the past
# postrm remove|purge
# - disable the configuration, mark it as automatically disabled in remove
# - disable the configuration, remove any trace we have on purge
case "$APACHE2_MAINTSCRIPT_NAME" in
preinst)
apache2_msg "info" "apache2_needs_action: The maintainer helper can not be called in preinst"
return 1
;;
prerm|postrm)
case "$APACHE2_MAINTSCRIPT_METHOD" in
remove|purge)
return 0
;;
*)
return 1
;;
esac
;;
postinst)
if [ "$APACHE2_MAINTSCRIPT_METHOD" = "configure" ] ; then
# act on fresh installs
[ -z "$APACHE2_MAINTSCRIPT_ARGUMENT" ] && return 0
# act if someone told us
[ -n "$APACHE2_NEED_ACTION" ] && return 0
fi
;;
esac
return 1
}
#
# Function apache2_has_module
# checks whether a supplied module is enabled in the current Apache server
# configuration
# Parameters:
# module - the module name which should be checked. Can be a regular
# string or a Perl compatible regular expression e.g. cgi(d|)
# Returns:
# 0 if the module(s) was/were found
# 1 otherwise
# Since: 2.4.1-1
apache2_has_module()
{
[ -x /usr/sbin/a2query ] || return 1
local MODULE="$1"
if a2query -m "$MODULE" > /dev/null ; then
return 0
fi
return 1
}
#
# Function apache2_switch_mpm
# switches the MPM enabled on the web server. This function switches the
# MPM unconditionally but does careful checks to make sure the web server
# is left back with a working MPM.
# It checks whether the supplied MPM exists and enables it on purpose.
# Parameters:
# mpm - change the MPM to the supplied argument. It should be given
# without "mpm_" prefix, e.g. "worker", "prefork", and so on.
# Returns:
# 0 if the MPM could be changed
# 1 otherwise
# Since: 2.4.1-1
apache2_switch_mpm()
{
[ -x /usr/sbin/a2query ] || return 1
[ -x /usr/sbin/a2dismod ] || return 1
[ -x /usr/sbin/a2enmod ] || return 1
local MPM="$1"
MPM="${MPM#mpm_}"
if [ -n "$APACHE2_MAINTSCRIPT_DEFER" ] ; then
echo "$APACHE2_MAINTSCRIPT_PACKAGE apache2_switch_mpm $*" >> $APACHE2_MAINTSCRIPT_DEFER
return 0
fi
if [ ! -e "/etc/apache2/mods-available/mpm_$MPM.load" ] ; then
apache2_msg "err" "apache2_switch_mpm: MPM $MPM not found"
return 1
fi
local a2query_ret=0
a2query -m "mpm_$MPM" > /dev/null 2>&1 || a2query_ret=$?
case $a2query_ret in
0)
apache2_msg "info" "apache2_switch_mpm $MPM: No action required"
return 0
;;
32)
apache2_msg "info" "apache2_switch_mpm $MPM: Has been disabled manually, not changing"
return 1
;;
esac
local CUR_MPM=$(a2query -M) || return 1
a2dismod -m -q "mpm_$CUR_MPM";
a2enmod -m -q "mpm_$MPM";
apache2_msg "info" "apache2_switch_mpm Switch to $MPM"
if ! apache2_has_module "mpm_$MPM" ; then
# rollback
a2enmod -m -q "mpm_$CUR_MPM"
apache2_msg "warning" "apache2_switch_mpm Switch to $MPM failed. Rolling back to $CUR_MPM"
return 1
fi
APACHE2_NEED_ACTION=1
apache2_reload restart
return 0
}
#
# Function apache2_invoke
# invokes an Apache 2 configuration helper to enable or disable a
# particular piece of configuration, a site or a module. It carefully
# checks whether the supplied configuration snippet exists and reloads the
# web server if the site administrator desires that by calling the
# apache2_reload function.
# Parameters:
# command - The command to invoke. Recognized commands are "enconf",
# "enmod", "ensite", "disconf", "dismod", "dissite"
# arguments
# - A single argument (e.g. a module) which shall be
# enabled or disabled respectively. Do not enable module
# dependencies that way, instead use module dependencies as
# documented in </usr/share/doc/apache2/PACKAGING>.
# rcd-action
# - An optional rc.d action to override the default which is to
# reload the web server for sites and configurations but restart
# it for modules. Recognized arguments are "restart" and "reload"
# Returns
# 0 if the changes could be activated
# 1 otherwise
# Since: 2.4.1-3
# Changes: 2.4.2-2: Added the second, optional argument
# 2.4.6-4: Allow apache2_invoke to disable configuration in preinst/postinst
apache2_invoke()
{
local CMD="$1"
local CONF="$2"
local RCD_ACTION="$3"
local invoke_rcd=0
local check_switch=""
local invoke_string=""
[ -x "/usr/sbin/a2$CMD" ] || return 1
[ -x "/usr/sbin/a2query" ] || return 1
if [ -n "$APACHE2_MAINTSCRIPT_DEFER" ] ; then
echo "$APACHE2_MAINTSCRIPT_PACKAGE apache2_invoke $*" >> "$APACHE2_MAINTSCRIPT_DEFER"
return 0
fi
case "${RCD_ACTION:-}" in
""|reload|restart)
;;
*)
return 1
;;
esac
case "$CMD" in
*conf)
check_switch="-c"
invoke_string="configuration"
rcd_action="${RCD_ACTION:-reload}"
;;
*mod)
check_switch="-m"
invoke_string="module"
rcd_action="${RCD_ACTION:-restart}"
;;
*site)
check_switch="-s"
invoke_string="site"
rcd_action="${RCD_ACTION:-reload}"
;;
*)
;;
esac
case "$CMD" in
enconf|enmod|ensite)
local a2query_ret=0
a2query $check_switch "$CONF" > /dev/null 2>&1 || a2query_ret=$?
if [ "$a2query_ret" -eq 0 ] ; then
# configuration is already enabled
apache2_msg "info" "apache2_invoke $CONF: already enabled"
APACHE2_NEED_ACTION=1
elif [ "$a2query_ret" -eq 32 ] ; then
# the admin disabled the module
apache2_msg "info" "apache2_invoke $CONF: no action - $invoke_string was disabled by local admin"
return 0
else
# coming here either means:
# a) we have no clue about the module (e.g. for upgrades prior to maintscript-helper
# b) it's a fresh install
APACHE2_NEED_ACTION=1
a2$CMD -m -q "$CONF" > /dev/null 2>&1 || return 1
apache2_msg "info" "apache2_invoke: Enable $invoke_string $CONF"
fi
;;
disconf|dismod|dissite)
local a2query_ret=0
a2query $check_switch "$CONF" > /dev/null 2>&1 || a2query_ret=$?
if [ "$a2query_ret" -eq 0 ] ; then
if [ "$APACHE2_MAINTSCRIPT_NAME" = 'postrm' ] && [ "$APACHE2_MAINTSCRIPT_METHOD" = "purge" ] ; then
a2$CMD -p -f -q "$CONF" || return 1
apache2_msg "info" "apache2_invoke $APACHE2_MAINTSCRIPT_NAME: Purging $invoke_string $CONF"
APACHE2_NEED_ACTION=1
elif [ "$APACHE2_MAINTSCRIPT_NAME" = 'postrm' ] || [ "$APACHE2_MAINTSCRIPT_NAME" = 'prerm' ] ||
[ "$APACHE2_MAINTSCRIPT_NAME" = 'postinst' ] || [ "$APACHE2_MAINTSCRIPT_NAME" = 'preinst' ] ; then
if [ "$APACHE2_MAINTSCRIPT_METHOD" = "remove" ] ; then
a2$CMD -m -f -q "$CONF" || return 1
apache2_msg "info" "apache2_invoke $APACHE2_MAINTSCRIPT_NAME: Disable $invoke_string $CONF"
APACHE2_NEED_ACTION=1
fi
else
apache2_msg "error" "apache2_invoke: $invoke_string $CONF not supported in $APACHE2_MAINTSCRIPT_NAME"
return 1
fi
elif [ "$a2query_ret" -eq 32 ] || [ "$a2query_ret" -eq 33 ] ; then
if [ "$APACHE2_MAINTSCRIPT_NAME" = 'postrm' ] && [ "$APACHE2_MAINTSCRIPT_METHOD" = "purge" ] ; then
apache2_msg "info" "apache2_invoke $APACHE2_MAINTSCRIPT_NAME: Purging state for $CONF"
# this will return RC=1
( a2$CMD -p -f -q "$CONF" > /dev/null 2>&1 )
else
apache2_msg "info" "apache2_invoke $CONF $APACHE2_MAINTSCRIPT_NAME: No action required"
fi
else
apache2_msg "info" "apache2_invoke $CONF $APACHE2_MAINTSCRIPT_NAME: No action required"
fi
;;
*)
return 1
;;
esac
if [ -n "${APACHE2_NEED_ACTION:-}" ] ; then
apache2_reload $rcd_action
fi
}
#
# Function apache2_reload
# reloads the web server to activate a changed configuration. It does not
# actually reload the web server if the current configuration fails to
# parse.
# Parameters:
# action - optional, can be 'reload' (default) or 'restart'
# Returns:
# 0 if the changes could be activated
# 1 otherwise
# Since: 2.4.1-1
apache2_reload()
{
if ! apache2_needs_action ; then
return 0
fi
if [ -n "$APACHE2_MAINTSCRIPT_DEFER" ] ; then
return 0
fi
local action
case "${1:-}" in
""|reload)
action=reload
;;
restart)
action=restart
;;
*)
return 1
;;
esac
local tmpfile=$(mktemp)
if apache2ctl configtest > $tmpfile 2>&1; then
invoke-rc.d apache2 $action || true
else
apache2_msg "err" "apache2_reload: Your configuration is broken. Not ${action}ing Apache 2"
grep -v -e "Action 'configtest' failed." \
-e "The Apache error log may have more information." \
"$tmpfile" |
while read LINE ; do
apache2_msg "err" "apache2_reload: $LINE"
done
fi
rm -f "$tmpfile"
}
# vim: syntax=sh sw=8 sts=8 sr noet
Mini Shell