ssm/ssm
fbt 8fdd73af45 More flexibility
Signed-off-by: fbt <fbt@fleshless.org>
2017-12-08 16:39:05 +03:00

528 lines
10 KiB
Bash
Executable File

#!/usr/bin/env bash
shopt -s nullglob
# Utility functions
## Make setting default values a bit less awkward
default() {
declare -n _p=$1; shift
[[ "$_p" ]] || {
for v in "$@"; do
_p+=( "$v" )
done
}
}
## Die. Why not?
die() {
declare code=${1:-0}
[[ "$2" ]] && printf '%s\n' "$2"
exit "$code"
}
## Run the command and wait for it to die
svc() {
declare job_pid
svc::cleanup() {
kill -n "$service_stop_signal" "$job_pid"
pid_wait "$job_pid" && {
rm -f "$svc_pidfile" "$service_ready_flag"
}
}; trap 'svc::cleanup' TERM
"$@" & job_pid=$!
printf '%s' "$job_pid" > "$svc_pidfile"
wait "$job_pid"
svc::cleanup
}
## Respawn
respawn() {
declare jobs job_pid
respawn::cleanup() {
jobs=( $(jobs -p) )
if [[ "$jobs" ]]; then
kill -n 15 "${jobs[@]}"
wait "${jobs[@]}"
fi
rm -f "$svc_pidfile" "$service_ready_flag"
exit 0
}; trap 'respawn::cleanup' TERM
respawn::sigpass() {
declare sig=$1 pid=$2
kill -n "$sig" "$pid"
}
respawn::set_traps() {
for s in "${service_signals[@]}"; do
trap "respawn::sigpass $s \$job_pid" "$s"
done
}; respawn::set_traps
while true; do
exec "$@" & job_pid=$!
while nullexec kill -n 0 "$job_pid"; do
wait "$job_pid"
done
done
}
## Run a command with its output discarded
nullexec() {
"$@" &>/dev/null
}
## Wait for a pid to die
pid_wait() {
declare cnt=0
while nullexec kill -0 "$1"; do
(( cnt >= (service_stop_timeout*10) )) && return 1
sleep 0.1
(( cnt++ ))
done
return 0
}
## See if NAME is a function
is_function() {
declare name=$1 name_type
name_type=$( type -t "$name" )
if [[ $name_type == 'function' ]]; then
return 0
fi
return 1
}
## Simple timer
timer() {
declare cnt=0 timeout=$1
shift
while ! "$@"; do
(( cnt >= (timeout*10) )) && return 1
sleep 0.1
(( cnt++ ))
done
return 0
}
## Is a service ready?
is_ready() [[ -f "$service_ready_flag" ]]
## Wait for this service to get ready
wait_ready() {
timer "$service_ready_timeout" is_ready
}
## Depend on other services to be started
depend() {
declare s
for s in "$@"; do
if ! "$0" "$s" qstatus; then
nullexec "$0" "$s" start || {
failed_deps+=( "$s" )
return 1
}
fi
done
}
## Create tmpfiles
mktmpfiles() {
declare f
for f in "${service_tmpfiles[@]}"; do
IFS=':' read -r f_path f_type f_args <<< "$f"
if ! [[ -e $f_path ]]; then
case "$f_type" in
symlink) ln -s "$f_args" "$f_path";;
file|dir) IFS=':' read -r f_perms f_owner f_group <<< "$f_args"
if [[ $f_type == 'file' ]]; then
> "$f_path"
chmod "${f_perms:-644}" "$f_path"
elif [[ "$f_type" == 'dir' ]]; then
mkdir -p -m "${f_perms:-755}" "$f_path"
fi
if [[ "$f_owner" || "$f_group" ]]; then
chown "${f_owner:-root}:${f_group:-root}" "$f_path"
fi;;
esac
fi
done
}
## Depend on other services to be ready
depend_ready() {
declare s
depend "$@" || return 1
for s in "$@"; do
"$0" "$s" wait_ready || {
failed_deps+=( "$s" )
return 1
}
done
}
# Super functions
## Start the service, write down the svc pid
super_start() {
(( service_running )) && return 3
rm -f "$service_stopped_flag"
[[ -f "${service_command[0]}" ]] || return 9
depend "${service_depends[@]}" || return 7
depend_ready "${service_depends_ready[@]}" || return 7
mktmpfiles || return 13
if (( service_managed )); then
if (( service_respawn )); then
svc respawn "${service_command[@]}" &>"$service_logfile" &
else
svc "${service_command[@]}" &>"$service_logfile" &
fi
if timer "$service_ready_timeout" ready; then
printf '1' > "$service_ready_flag"
else
return 5
fi
elif (( service_oneshot )); then
"${service_command[@]}" &>"$service_logfile"; res=$?
(( $res )) && return "$res"
printf '1' > "$service_enabled_flag"
else
exec "${service_command[@]}" &
fi
return 0
}
# A separate function for oneshot services
super_oneshot() {
(( service_enabled )) && return 3
}
## Reload the service
## Usually just sends HUP
super_reload() {
(( service_running )) || return 3
if (( service_managed )); then
kill -n 1 "$service_pid"
else
kill -n "$service_reload_signal" "$service_pid"
fi
}
## Stop the service
## Returns:
## 3: Service is not running.
super_stop() {
if (( service_oneshot )); then
(( service_enabled )) || return 3
rm -f "$service_enabled_flag"
return 0
else
(( service_running )) || return 3
nullexec kill -n "$service_stop_signal" "$service_pid" || return 1
pid_wait "$service_pid" || return 5
> "$service_stopped_flag"
return 0
fi
}
info() {
declare \
_status_label='Running' \
_status='no'
_type='daemon'
_info_items=()
(( service_oneshot )) && {
_status_label='Enabled'
_type='oneshot'
}
status && _status='yes'
_info_items=(
"Name" "$service_name"
"Type" "$_type"
"$_status_label" "$_status"
"Exec" "${service_command[*]} ${service_args[*]}"
"Respawn" "${service_respawn:-false}"
)
[[ "$_status" == 'yes' ]] && {
_info_items+=(
"PIDfile" "${service_pidfile:-none}"
"PID" "${service_pid:-none}"
)
}
printf "%12s: %s\n" "${_info_items[@]}"
}
result() {
declare rc=$1; shift
declare -A msgs
while (( $# )); do
[[ "$2" ]] || return 1
msgs["$1"]="$2"
shift 2
done
[[ "${msgs[$rc]}" ]] || msgs["$rc"]="Failed!"
printf '%s\n' "${msgs[$rc]}"
}
# Overloadable functions
start() { super_start; }
stop() { super_stop; }
reload() { super_reload; }
restart() {
"$0" "$service_name" stop
"$0" "$service_name" start
}
logs() { ${PAGER:-less} "$service_logfile"; }
## Status is a bit of a special case. It's talkative.
status() {
(( service_running )) && return 0
(( service_enabled )) && return 0
(( service_stopped )) && return 7
return 1
}
## For use in scripts
qstatus() { nullexec status; }
## By default there is no ready check
ready() { :; }
# Code
main() {
# Needs to be global
declare -g service_pid
# Let's set some defaults
service_managed=1
usrdir='/usr/share/ssm'
if (( $UID )); then
# XDG stuff
default XDG_CONFIG_HOME "$HOME/.config"
default XDG_RUNTIME_DIR "/run/user/$UID"
service_path=( "$XDG_CONFIG_HOME/ssm/services" )
cfg_path=( "$XDG_CONFIG_HOME/ssm" )
rundir="$XDG_RUNTIME_DIR/ssm"
logdir="$HOME/log/ssm"
else
rundir='/run/ssm'
logdir='/var/log/ssm'
fi
# Common service path
service_path+=( '/etc/ssm/init.d' "$rundir/services" "$usrdir/services" )
# Common config path
cfg_path+=( '/etc/ssm/conf.d' )
# Load custom functions
for p in "${cfg_path[@]}"; do
for f in "$p/functions"/*; do
source "$f" || die 9 "Failed to source functions from $f"
done
done
# Now create the needed runtime stuff
for d in "$rundir" "$logdir"; do
mkdir -p "$d" || die 3 "Failed to create runtime dir: $d"
done
# If $1 is a full path, source it.
# If not, search for it in the service path.
if [[ $1 == /* ]]; then
service_config=$1
else
for i in "${service_path[@]}"; do
[[ -f "$i/$1" ]] && {
service_config="$i/$1"
break
}
done
fi
# Die if there is no such file
[[ "$service_config" ]] || die 19 "Service not found: $1"
# Service name is the basename
service_name="${1##*/}"
# Semi-hardcoded stuff
svc_pidfile="$rundir/$service_name.pid"
# Get the service defaults
for p in "${cfg_path[@]}"; do
[[ -f "$p/conf.d/$service_name" ]] && {
source "$p/conf.d/$service_name" || die 5 "Failed to read service defaults: $p/conf.d/$service_name"
break
}
done
# Get the service config
source -- "$service_config" "${@:3}" || die 7 "Failed to read the service config: $service_config"
# Legacy
[[ "$service_args" ]] && service_command=( "${service_command[@]}" "${service_args[@]}" )
[[ "$service_respawn" == 'true' ]] && service_respawn=1
[[ "$service_type" == 'oneshot' ]] && service_oneshot=1
(( service_oneshot )) && service_managed=0
[[ "$service_pidfile" ]] && service_managed=0
if ! (( service_managed )); then
(( service_respawn )) && die 21 "Refusing to respawn a service that manages itself."
fi
# Service-level defaults
default service_pidfile "$svc_pidfile"
default service_logfile "$logdir/$service_name.log"
default service_ready_flag "$rundir/$service_name.ready"
default service_enabled_flag "$rundir/$service_name.enabled"
default service_stopped_flag "$rundir/$service_name.stopped"
default service_stop_timeout 30
default service_ready_timeout 15
default service_stop_signal 15
default service_reload_signal 1
default service_signals 1 10 12
# Let's see if there's a PID
if [[ -f "$service_pidfile" ]]; then
service_pid=$(<$service_pidfile)
# Let's see if it's running
if nullexec kill -0 "$service_pid"; then
service_running=1
fi
fi
# Maybe the service is enabled?
if [[ -f "$service_enabled_flag" ]]; then
# Yay, it is!
service_enabled=1
fi
# Let's see if the service was deliberately stopped
if [[ -f "$service_stopped_flag" ]]; then
# Ooh, it was.
service_stopped=1
fi
# Check if action is even defined
is_function "$2" || die 17 "Function $2 is not defined for $service_name."
# cd into the workdir, if defined.
[[ "$service_workdir" ]] && {
cd "$service_workdir" || die $?
}
# Run pre_$action function
if is_function "pre_$2"; then
"pre_$2" || {
printf 'pre_%s failed!\n' "$2"
die 13
}
fi
# Run the function
"$2"; res=$?
case "$2" in
stop)
result "$res" \
0 "Stopped $service_name" \
3 "$service_name is not running" \
5 "Operation timed out"
;;
start)
result "$res" \
0 "Started $service_name" \
3 "$service_name is already running" \
5 "Readyness check for $service_name timed out" \
7 "Failed to start dependencies for $service_name: ${failed_deps[@]}" \
9 "service_command does not exist: ${service_command[0]}" \
13 "Failed to create temporary files for $service_name"
;;
reload)
result "$res" \
0 "Reloaded $service_name"
;;
status)
if (( service_oneshot )); then
result "$res" \
0 "$service_name is enabled" \
1 "$service_name is not enabled"
else
result "$res" \
0 "$service_name is running" \
1 "$service_name is not running" \
7 "$service_name was stopped"
fi
;;
esac
(( res )) && return "$res"
# Run post_$action function
if is_function "post_$2"; then
"post_$2" || {
printf 'post_%s failed!\n' "$2"
die 15
}
fi
}
main "$@"