# This comes from the dracut-logger.sh
# The logger defined 4 logging levels:
# The DEBUG Level designates fine-grained informational events that are most
# useful to debug an application.
# The INFO level designates informational messages that highlight the
# progress of the application at coarse-grained level.
# The WARN level designates potentially harmful situations.
# The ERROR level designates error events that might still allow the
# application to continue running.
# Logging is controlled by following global variables:
# - @var kdump_stdloglvl - logging level to standard error (console output)
# - @var kdump_sysloglvl - logging level to syslog (by logger command)
# - @var kdump_kmsgloglvl - logging level to /dev/kmsg (only for boot-time)
# If any of the variables is not set, the function dlog_init() sets it to default:
# - @var kdump_stdloglvl = 3 (info)
# - @var kdump_sysloglvl = 0 (no logging)
# - @var kdump_kmsgloglvl = 0 (no logging)
# - @var kdump_stdloglvl = 0 (no logging)
# - @var kdump_sysloglvl = 3 (info)
# - @var kdump_kmsgloglvl = 0 (no logging)
# First of all you have to start with dlog_init() function which initializes
# required variables. Don't call any other logging function before that one!
# Define vairables for the log levels in this module.
# The dracut-lib.sh is only available in the second kernel, and it won't
# be used in the first kernel because the dracut-lib.sh is invisible in
if [ -f /lib/dracut-lib.sh ]; then
# @brief Get the log level from kernel command line.
# @retval 1 if something has gone wrong
(type -p getarg) && kdump_sysloglvl=$(getarg rd.kdumploglvl)
[ -z "$kdump_sysloglvl" ] && return 1;
(type -p isdigit) && isdigit $kdump_sysloglvl
[ $? -ne 0 ] && return 1;
# @brief Check the log level.
# @retval 1 if something has gone wrong
# @brief Initializes Logger.
# @retval 1 if something has gone wrong
local ret=0; local errmsg
if [ -s /proc/vmcore ];then
logger -t "kdump[$$]" -p warn -- "Kdump is using the default log level(3)."
kdump_stdloglvl=$KDUMP_STDLOGLVL
kdump_sysloglvl=$KDUMP_SYSLOGLVL
kdump_kmsgloglvl=$KDUMP_KMSGLOGLVL
[ -z "$kdump_stdloglvl" ] && kdump_stdloglvl=3
[ -z "$kdump_sysloglvl" ] && kdump_sysloglvl=0
[ -z "$kdump_kmsgloglvl" ] && kdump_kmsgloglvl=0
for loglvl in "$kdump_stdloglvl" "$kdump_kmsgloglvl" "$kdump_sysloglvl"; do
echo "Illegal log level: $kdump_stdloglvl $kdump_kmsgloglvl $kdump_sysloglvl"
# Skip initialization if it's already done.
[ -n "$kdump_maxloglvl" ] && return 0
if [[ $UID -ne 0 ]]; then
if [[ $kdump_sysloglvl -gt 0 ]]; then
if [[ -d /run/systemd/journal ]] \
&& type -P systemd-cat &>/dev/null \
&& systemctl --quiet is-active systemd-journald.socket &>/dev/null; then
readonly _systemdcatfile="/var/tmp/systemd-cat"
mkfifo "$_systemdcatfile" &>/dev/null
systemd-cat -t 'kdump' --level-prefix=true <"$_systemdcatfile" &
exec 15>"$_systemdcatfile"
elif ! [ -S /dev/log -a -w /dev/log ] || ! command -v logger >/dev/null; then
# We cannot log to syslog, so turn this facility off.
kdump_kmsgloglvl=$kdump_sysloglvl
errmsg="No '/dev/log' or 'logger' included for syslog logging"
local lvl; local maxloglvl_l=0
for lvl in $kdump_stdloglvl $kdump_sysloglvl $kdump_kmsgloglvl; do
[[ $lvl -gt $maxloglvl_l ]] && maxloglvl_l=$lvl
readonly kdump_maxloglvl=$maxloglvl_l
if [[ $kdump_stdloglvl -lt 4 ]] && [[ $kdump_kmsgloglvl -lt 4 ]] && [[ $kdump_sysloglvl -lt 4 ]]; then
if [[ $kdump_stdloglvl -lt 3 ]] && [[ $kdump_kmsgloglvl -lt 3 ]] && [[ $kdump_sysloglvl -lt 3 ]]; then
if [[ $kdump_stdloglvl -lt 2 ]] && [[ $kdump_kmsgloglvl -lt 2 ]] && [[ $kdump_sysloglvl -lt 2 ]]; then
if [[ $kdump_stdloglvl -lt 1 ]] && [[ $kdump_kmsgloglvl -lt 1 ]] && [[ $kdump_sysloglvl -lt 1 ]]; then
[ -n "$errmsg" ] && derror "$errmsg"
## @brief Converts numeric level to logger priority defined by POSIX.2.
# @param lvl Numeric logging level in range from 1 to 4.
# @retval 1 if @a lvl is out of range.
# @retval 0 if @a lvl is correct.
# @result Echoes logger priority.
## @brief Converts logger numeric level to syslog log level
# @param lvl Numeric logging level in range from 1 to 4.
# @retval 1 if @a lvl is out of range.
# @retval 0 if @a lvl is correct.
# @result Echoes kernel console numeric log level
# Conversion is done as follows:
# ERROR(1) -> LOG_ERR (3)
# WARN(2) -> LOG_WARNING (4)
# INFO(3) -> LOG_INFO (6)
# DEBUG(4) -> LOG_DEBUG (7)
# @see /usr/include/sys/syslog.h
# The number is constructed by multiplying the facility by 8 and then
# About The Syslog Protocol, please refer to the RFC5424 for more details.
## @brief Prints to stderr, to syslog and/or /dev/kmsg given message with
# given level (priority).
# @param lvl Numeric logging level.
# @retval 0 It's always returned, even if logging failed.
# @note This function is not supposed to be called manually. Please use
# dinfo(), ddebug(), or others instead which wrap this one.
# This is core logging function which logs given message to standard error
# and/or syslog (with POSIX shell command <tt>logger</tt>) and/or to /dev/kmsg.
# The format is following:
# <tt>X: some message</tt>
# where @c X is the first letter of logging level. See module description for
# Message to syslog is sent with tag @c kdump. Priorities are mapped as
# - @c WARN to @c warning
[[ $lvl -le $kdump_stdloglvl ]] && printf -- 'kdump: %s\n' "$msg" >&2
if [[ $lvl -le $kdump_sysloglvl ]]; then
if [[ "$_dlogfd" ]]; then
printf -- "<%s>%s\n" "$(($(_dlvl2syslvl $lvl) & 7))" "$msg" >&$_dlogfd
logger -t "kdump[$$]" -p $(_lvl2syspri $lvl) -- "$msg"
[[ $lvl -le $kdump_kmsgloglvl ]] && \
echo "<$(_dlvl2syslvl $lvl)>kdump[$$] $msg" >/dev/kmsg
## @brief Internal helper function for _do_dlog()
# @param lvl Numeric logging level.
# @retval 0 It's always returned, even if logging failed.
# @note This function is not supposed to be called manually. Please use
# dinfo(), ddebug(), or others instead which wrap this one.
# This function calls _do_dlog() either with parameter msg, or if
# none is given, it will read standard input and will use every line as
# dwarn "This is a warning"
# echo "This is a warning" | dwarn
[ -z "$kdump_maxloglvl" ] && return 0
[[ $1 -le $kdump_maxloglvl ]] || return 0
while read line || [ -n "$line" ]; do
## @brief Logs message at DEBUG level (4)
# @retval 0 It's always returned, even if logging failed.
[ -n "$debug" ] && set -x || :
## @brief Logs message at INFO level (3)
# @retval 0 It's always returned, even if logging failed.
[ -n "$debug" ] && set -x || :
## @brief Logs message at WARN level (2)
# @retval 0 It's always returned, even if logging failed.
[ -n "$debug" ] && set -x || :
## @brief It's an alias to dwarn() function.
# @retval 0 It's always returned, even if logging failed.
[ -n "$debug" ] && set -x || :
## @brief Logs message at ERROR level (1)
# @retval 0 It's always returned, even if logging failed.
[ -n "$debug" ] && set -x || :
It is recommended that you Edit text format, this type of Fix handles quite a lot in one request
