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#######################################################
# Include: Set functions needed by vmchooser-run_virt #
#######################################################
## Assigns an ID to the currently starting VM to support
# multiple instances running simultaneously.
# Note that VM_ID will always have two digits.
get_vm_id() {
local script=${BASH_SOURCE[-1]}
[ -z "$script" ] && script="$0"
if [ -n "$script" ]; then
script=$(readlink -f "$script")
if [ -n "$script" ] && [ -s "$script" ]; then
#bingo
declare -g VM_ID=$(ps ax | grep -F "$script" | grep -v 'grep' | grep -o -- "${script}.*\$" | sort -u | wc -l)
if [ "$VM_ID" -gt 0 ]; then
[ "${#VM_ID}" -eq 1 ] && VM_ID="0${VM_ID}"
[ "${#VM_ID}" -gt 2 ] && VM_ID="${VM_ID:0:2}"
[ "${#VM_ID}" -eq 2 ] && readonly VM_ID && return
fi
fi
fi
# fallback: take last two digits of current pid...
VM_ID=$(expr substr $$ $(expr ${#$} - 1) 2)
[ "${#VM_ID}" -eq 1 ] && VM_ID="0${VM_ID}"
readonly VM_ID
}
################# LOGGING FUNCTIONS ##################
# Helper function to write to stdout and logfile
writelog() {
local DATE=$(date +%Y-%m-%d-%H-%M-%S)
# write to stdout?
if [ "x$1" = "x--quiet" ]; then
shift
else
echo -e "$DATE: $@"
fi
# log into file
echo -e "$DATE: ${SLX_DEBUG:+(${FUNCNAME[1]}) }$@" >> "${LOGFILE}"
}
# Helper function to notify the user.
# This directly returns and do not wait for a user confirmation.
notify_user() {
local TOPIC="$1"
shift
notify-send -u normal "$TOPIC" "$@"
writelog "Notify: **${TOPIC}**: $*"
}
# Helper to display an error message box to the user.
# Only returns when the user dismisses the message.
error_user() {
local TOPIC="$1"
shift
local MSG TITLE BODY
if [ $# -gt 0 ]; then
MSG=" $TOPIC
$*"
TITLE="$TOPIC"
BODY="$*"
else
MSG="$TOPIC"
TITLE="ERROR"
BODY="$TOPIC"
fi
# Zenity should yield the nicest result
# TODO the title is only set as the window name,
# which cannot be seen without a window manager
zenity --error --title "$TITLE" --text "$BODY"
local RET=$?
[ $RET -le 1 ] && return
# QnD abuse printergui for error message as it's blocking
/opt/openslx/cups/printergui --error "$MSG" && return
# printergui might not exist, try fallback here
# unfortunately, I can only think of notify+sleep right now
notify-send -u critical "$TITLE" "$BODY"
sleep 10
}
################## CLEANUP FUNCTIONS ##################
# Registers functions to be called when cleanexit is called.
# Only accepts functions that were not previously registered.
# This kinda detects when a cleanup function was overriden,
# or at least that something is fishy.
declare -ag CLEANUP_TASKS
add_cleanup() {
[ $# -lt 1 ] && writelog "'${FUNCNAME[0]}' needs at least one argument! $# given." && return
# check if the given function name is already used
while [ $# -ne 0 ]; do
if array_contains CLEANUP_TASKS "$1"; then
writelog "Cleanup function '$1' already registered! Are there multiple definitions of this function?"
writelog "This might suggest that a previously defined cleanup function was overriden!"
return 1
fi
CLEANUP_TASKS+=("$1")
shift
done
return 0
}
# This function will be called at the end of vmchooser-run_virt
# or upon critical errors during the runtime.
# It will call the cleanup functions registered through 'add_cleanup'
# and clean TMPDIR if appropriate. Further, it will evaluate and
# process the EXIT_{TYPE,REASON} variables that hold information
# on why we are about to exit.
#
# EXIT_TYPE should be either:
# - 'internal' for critical internal errors, this will
# automatically send the logfile via slxlog.
# - 'user' for errors related to the user's choice
# Others could be thought of like 'external' for failures
# with remote services (e.g. slx apis, external image repo, ...)
#
# EXIT_REASON should contain a user-friendly message to print to the user.
cleanexit() {
writelog "Cleanexit '$1' triggered by '${BASH_SOURCE[1]}:${FUNCNAME[1]}'"
sleep 1
while isset CLEANUP_TASKS; do
local TASK=${CLEANUP_TASKS[-1]}
unset -v CLEANUP_TASKS[-1]
if ! is_function $TASK; then
writelog "Registered cleanup function '$TASK' is not a function. This should not be..."
continue
fi
if ! ${TASK}; then
writelog "Failed to run cleanup function '$TASK'! Exit code: $RET"
fi
done
# If we're not in debug mode, remove all temporary files
if notempty SLX_DEBUG && isset TMPDIR; then
rm -rf -- "${TMPDIR}"
fi
# Now see if we need to do the catch all error stuff
# if 0 given, exit 0
[ "x$1" = "x0" ] && exit 0
# if no code was given, exit 129
[ $# -eq 0 ] && writelog "Cleanexit called without arguments! Dev error?"
# given exit code is set and not 0, handle the error now
# now evaluate the EXIT_{TYPE,REASON} variables and generate error title/text
local ERR_TITLE ERR_TEXT ERR_FOOTER
# default error footer
ERR_FOOTER="Versuchen Sie den Computer neuzustarten und falls das Problem bestehen bleibt, kontaktieren Sie den Support."
if notempty EXIT_TYPE; then
case "${EXIT_TYPE}" in
user)
ERR_TITLE="Auswahlfehler"
ERR_FOOTER="Beim Start Ihrer Veranstaltung sind Fehler aufgetretten. Versuchen Sie es mit einer anderen Veranstaltung."
;;
internal)
ERR_TITLE="Interner Fehler"
;;
*)
ERR_TITLE="Unbekannter Fehler"
writelog "Unknown EXIT_TYPE: '${EXIT_TYPE}'."
;;
esac
fi
if notempty EXIT_REASON; then
ERR_TEXT="${EXIT_REASON}"
else
# this should never happen if EXIT_REASON is properly
# used when calling cleanexit !
ERR_TEXT="Unbekannter Fehler"
fi
# first send the logfile (in case the user does not close the error before using magic keys e.g.)
# for any other error types besides 'user'. Do no slxlog if we run wrapped (from /opt/openslx/scripts/vmchooser-run_virt)
[ "x${EXIT_TYPE}" != "xuser" ] && ! isset WRAPPED && \
slxlog "runvirt-exit-${EXIT_TYPE}" "Critical error happened in '${BASH_SOURCE[1]}:${FUNCNAME[1]}', see logs." "${LOGFILE}"
# finally display the error
error_user "${ERR_TITLE}" "
${ERR_TEXT}
${ERR_FOOTER}
"
writelog "All done. Exiting."
# if no exit code was given as $1, exit 129
exit "${1:-129}"
}
################# SOURCING FUNCTIONS #################
# Wrapped 'source' that first checks for existence and
# syntax before actually sourcing the given file.
# The option '--exit' triggers cleanexit upon syntax errors.
# Without it, it returns 0 when tests passed, 1 otherwise.
# Usage:
# safesource [--exit] <files>
safesource() {
declare -i EXIT_ON_FAILURE=0
[ "x$1" = "x--exit" ] && EXIT_ON_FAILURE=1 && shift
while [ $# -gt 0 ]; do
# sanitze filename just to be sure as it is part of the eval coming later
# alphanumeric and - _ . should be enough for common file naming scheme
if [[ ! "$1" =~ ^[a-zA-Z0-9./_-]+$ ]]; then
writelog "'$1' is a weird filename to source! Ignoring."
return 1
fi
local FILE="$1"
shift
bash -n "${FILE}"
local -i RET=$?
if [ $RET -ne 0 ]; then
case $RET in
1) writelog --quiet "Bad file to source: ${FILE}" ;;
2) writelog --quiet "Bad syntax: ${FILE}" ;;
126) writelog --quiet "Could not access: ${FILE}" ;;
127) writelog --quiet "File not found: ${FILE}" ;;
*) writelog --quiet "Syntax check (bash -n) returned unknown error code '${RET}' for: ${FILE}" ;;
esac
if [ $EXIT_ON_FAILURE -eq 1 ]; then
echo "eval EXIT_REASON=\"internal:source:${FILE}\" cleanexit 1 ;"
else
echo "eval writelog \"Could not safesource '${FILE}'.\" ;"
fi
return 1
fi
echo "eval source ${FILE} ;"
echo "run_post_source ${FILE} ;"
done
return 0
}
# Registers functions to be called after sourcing an include.
# Includes should only define functions and register them
# to be called after successfully sourcing.
declare -Ag RUN_POST_SOURCE
call_post_source() {
while [ $# -gt 0 ]; do
if ! is_function "$1"; then
writelog "Tried to register a non-function: '$1'"
continue
fi
if notempty BASH_SOURCE[1]; then
RUN_POST_SOURCE[${BASH_SOURCE[1]}]+="$1 "
shift
else
writelog "Could not determine the sourced file calling ${FUNCNAME[0]}"
fi
done
}
# Helper called after sourcing the file via safesource. It just calls the
# functions in the same order they were registered.
run_post_source() {
[ $# -ne 1 ] && writelog "'${FUNCNAME[0]}' expects one argument only! $# given." && return 1
for TASK in ${RUN_POST_SOURCE["${1}"]}; do
# sanity checks
if ! is_function $TASK; then
writelog "\tRegistered function '$TASK' is not a function!"
return 1 # TODO maybe even cleanexit here as this seems very bad...
fi
# remove from stack before running it
RUN_POST_SOURCE["${1}"]="${RUN_POST_SOURCE[${1//${TASK}\ /\ }]}"
${TASK}
local -i RET=$?
if [ $RET -ne 0 ]; then
writelog "\tFailed to run post source '${TASK}' (Exit code: $RET)"
return $RET
fi
done
return 0
}
################# FEATURE FUNCTIONS ##################
# Helper to register feature handlers, read run-virt.d/README
declare -Ag FEATURE_HANDLERS
reg_feature_handler() {
if [ $# -ne 2 ]; then
writelog "'${FUNCNAME[0]}' expects 2 arguments! $# given."
return 1
fi
if notempty FEATURE_HANDLERS["$1"]; then
writelog "'${BASH_SOURCE[1]}' tried to overwrite feat handler '$1'! Ignoring."
# maybe allow overwritting?
return 1
fi
if ! is_function "$2"; then
writelog "'${BASH_SOURCE[1]}' tried to register a non-function as feat handler!"
writelog "\t'$2' is a '$(type -t $2 2>&1)'."
return 1
fi
# all good, save it
FEATURE_HANDLERS["$1"]="$2"
return 0
}
################### XML FUNCTIONS ####################
# Extract given xpath from given xml file
# e.g.: xmlextract '//node/nestednode/@attribute' "$file"
# @param
# @return Plain text, UTF-8
xmlextract() {
xmlstarlet sel -T -E utf-8 -t -v "$1" "$2"
}
# Wrapper for convenience
get_xml () {
xmlextract "//settings/eintrag/${1}/@param" "${XML_FILE}"
}
################## HELPER FUNCTIONS ##################
# Check if the given variables are set (empty or not)
isset() {
while [ $# -gt 0 ]; do
[ -z "${!1+x}" ] && return 1
shift
done
return 0
}
# Check if the given variables are not empty
notempty() {
while [ $# -gt 0 ]; do
[ -z "${!1}" ] && return 1
shift
done
return 0
}
# Convenience function
isempty() {
! notempty $@
}
# Helper to test if given arguments are declared as functions
is_function() {
while [ $# -gt 0 ]; do
local TYPE="$(type -t "$1" 2>/dev/null)"
if [ "x${TYPE}" != "xfunction" ]; then
writelog "'$1' not a function but a '${TYPE}'."
return 1
fi
shift
done
return 0
}
# Helper to test if given arguments are declared as arrays
is_array() {
# -ne 1 ] && writelog "is_array: Expects 1 argument! $# given." && return 1
while [ $# -gt 0 ]; do
local ARRAY_DEF="$(declare -p ${1} 2>/dev/null)"
if [[ ! "${ARRAY_DEF}" =~ "declare -a" ]] && [[ ! "${ARRAY_DEF}" =~ "declare -A" ]]; then
return 1
fi
shift
done
return 0
}
# Helper to test is the given array contains given value
# Usage:
# array_contains ARRAY_TO_TEST <values...>
array_contains() {
if [ $# -lt 2 ]; then
#writelog "${FUNCNAME[0]}: Expects at least 2 arguments, $# given."
return 1
fi
# is $1 even defined?
local ARRAY_DEF="$(declare -p $1 2>/dev/null)"
if isempty ARRAY_DEF; then
#writelog "${FUNCNAME[0]}: '$1' not defined!"
return 1
fi
local ARRAY_NAME="$1"
shift
# sanity check on $ARRAY_DEF being either indexed or associative array
if ! is_array "${ARRAY_NAME}"; then
#writelog "${FUNCNAME[0]}: '${ARRAY_NAME}' not an array! Declared as:\t${ARRAY_DEF}"
return 1
fi
# now test if array contains the given values in $2+
while [ $# -gt 0 ]; do
# check if ARRAY_DEF contains '"<value>"'
if [[ ! "${ARRAY_DEF}" =~ '="'${1}'"'[^\]]+ ]]; then
#writelog "${FUNCNAME[0]}: '${1}' not in '${ARRAY_NAME}'"
return 1
fi
shift
done
return 0
}
# Helper to check if the given arguments are valid command names.
# This uses 'type -t' thus supports notably binaries, functions
# and aliases (might need these one day).
# By default, only 0 is returned if all arguments are found.
# Use '--oneof' to return 0 if any one of the arguments are found.
check_dep() {
[ $# -lt 1 ] && return 1
unset ONEOF
if [ "x$1" = "x--oneof" ]; then
local ONEOF="1"
shift
fi
while [ $# -gt 0 ]; do
if ! type -t "$1" >/dev/null 2>&1 ; then
writelog "Dependency check failed! Could not find '$1'."
isset ONEOF || return 1
else
isset ONEOF && return 0
fi
shift
done
isset ONEOF && return 1 || return 0
}
# TODO: This is only used once in the whole script:
# to cleanup the os string stored in the xml
# Since the rework of this script, the os strings come from
# the satellite server which already gives us a sanitized string
# thus this function might not be needed anymore, as calling it on
# new gen os strings effectively does nothing.
# Removes any non-alphanumerical and non-hyphen chars
# from the given parameters.
clean_string() {
if [ "$#" -ge 1 ]; then
echo "$@" | tr '[A-Z]' '[a-z]' | tr -d -c '[a-z0-9\-]'
else
tr '[A-Z]' '[a-z]' | tr -d -c '[a-z0-9\-]'
fi
}
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