mariadb: switch init to mysqld_safe and mysqladmin

mysqld_safe is the recommended way to start the server on non-systemd
systems ([1]). For instance, it has a crash detection with auto-restart
function, can update ulimits, setup core files, set the niceness of the
server etc. It looks like it could also be helpful when trying to set up
clusters. It's maintained upstream and adding it means we don't need to
add these features into our init script.

mysqld_safe is a script itself, so it's added to conffiles in case users
want to edit it.

It can't be run under procd, so the init script is converted to a normal
System V type. To stop the server and to reload the privileges tables
mysqladmin is used. To that end mysqladmin is moved into the server
package.

While changing the init script, the Debian init script was used for
ideas. It wasn't copied verbatim and adapted a bit here and there.
Thanks to whoever wrote it!

This commit removes the support for starting the service as a user other
than "mariadb". This makes the init script simpler. If anybody wants to
play around with the user then it's up to them to fix the permissions.

[1] https://mariadb.com/kb/en/mysqld_safe/

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

utils/mariadb/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=mariadb
 PKG_VERSION:=10.4.12
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL := \
@@ -123,7 +123,6 @@ MARIADB_CLIENT_EXTRA := \
 	mysql_find_rows \
 	mysql_waitpid \
 	mysqlaccess \
-	mysqladmin \
 	mysqldump \
 	mysqlimport \
 	mysqlshow \
@@ -134,7 +133,9 @@ MARIADB_SERVER := \
 	innochecksum \
 	my_print_defaults \
 	mysql_install_db \
-	mysqld
+	mysqladmin \
+	mysqld \
+	mysqld_safe
 
 MARIADB_SERVER_EXTRA := \
 	aria_chk \
@@ -156,6 +157,7 @@ MARIADB_SERVER_EXTRA := \
 	mysql_tzinfo_to_sql \
 	mysqlbinlog \
 	mysqld_multi \
+	mysqld_safe_helper \
 	mysqldumpslow \
 	mysqlhotcopy \
 	perror \
@@ -272,6 +274,10 @@ define Package/mariadb-server
   PROVIDES:=mysql-server
 endef
 
+define Package/mariadb-server/conffiles
+/usr/bin/mysqld_safe
+endef
+
 define Package/mariadb-server/description
 $(call Package/mariadb/description/Default)
 

utils/mariadb/files/mysqld.config

@@ -1,7 +1,5 @@
 
 config mysqld 'general'
-	option enabled '0'
+	option enabled '0'			# 0 - disabled, 1 - enabled
-	option log_stderr '1'
+	option options '--syslog'		# Options passed to mysqld_safe
-	option log_stdout '1'
-	option options ''
 

utils/mariadb/files/mysqld.init

@@ -4,48 +4,71 @@
 START=95
 STOP=10
 
-USE_PROCD=1
-
-#PROCD_DEBUG=1
-
 NAME=mysqld
 
 LOGGER="/usr/bin/logger -p user.err -s -t $NAME --"
-COMMAND=/usr/bin/$NAME
+
+MYSQLADMIN=/usr/bin/mysqladmin
+MYSQLD=/usr/bin/$NAME
+MYSQLDSAFE=/usr/bin/mysqld_safe
+
+# mysqladmin likes to read /root/.my.cnf which could cause issues.
+export HOME=/etc/mysql
+
+# Safeguard (relative paths, core dumps...)
+cd /
 
 mysqld_get_param() {
-	$COMMAND --print-defaults \
+	$MYSQLD --print-defaults \
 		| tr " " "\n" \
 		| grep -- "--$1" \
 		| tail -n 1 \
 		| cut -d= -f2
 }
 
-start_service() {
+# Checks if a server is running and accessible.
-	local conf=/etc/mysql/my.cnf
+#
-	local dir
+# check_alive insists on a pingable server
-	local user
+# check_dead also fails if there is a lost mysqld in the process list
-	local group
+#
-
+# Usage: boolean mysqld_status [check_alive|check_dead]
-	local logfile
+mysqld_status() {
-
+	if $MYSQLADMIN ping >/dev/null 2>&1; then
-	local datadir
+		ping_alive=1
-	local logdir=/var/log/mysql
+	else
-	local rundir=/var/run/mysqld
+		ping_alive=0
-	local tmpdir
-
-	local enabled
-	local log_stderr
-	local log_stdout
-	local options
-
-	local hint="please fix your server configuration in /etc/mysql/"
-
-	if [ ! -x $COMMAND ]; then
-		$LOGGER $COMMAND is missing
-		exit 1
 	fi
 
+	ps_alive=0
+	pidfile=$(mysqld_get_param pid-file)
+	if [ -f "$pidfile" ] && kill -0 $(cat "$pidfile") >/dev/null 2>&1; then
+		ps_alive=1
+	fi
+
+	if { [ "$1" = check_alive ] && [ $ping_alive = 1 ]; } || \
+		{ [ "$1" = check_dead ] && [ $ping_alive = 0 ] \
+					&& [ $ps_alive = 0 ]; }
+	then
+		return 0 # EXIT_SUCCESS
+	else
+		return 1 # EXIT_FAILURE
+	fi
+}
+
+start() {
+	conf=/etc/mysql/my.cnf
+	logdir=/var/log/mysql
+	rundir=/var/run/mysqld
+
+	hint="please fix your server configuration in /etc/mysql/"
+
+	for i in $MYSQLD $MYSQLADMIN $MYSQLDSAFE; do
+		if [ ! -x $i ]; then
+			$LOGGER $i is missing
+			exit 1
+		fi
+	done
+
 	if [ ! -r $conf ]; then
 		$LOGGER $conf cannot be read
 		exit 1
@@ -59,15 +82,10 @@ start_service() {
 		exit 1
 	fi
 
-	config_get_bool log_stderr general log_stderr 1
-	config_get_bool log_stdout general log_stdout 1
-
 	config_get options general options
 
 	datadir=$(mysqld_get_param datadir)
-	logfile=$(mysqld_get_param general_log_file)
 	tmpdir=$(mysqld_get_param tmpdir)
-	user=$(mysqld_get_param user)
 
 	if [ -z "$datadir" ]; then
 		$LOGGER datadir is not set
@@ -81,76 +99,48 @@ start_service() {
 		exit 1
 	fi
 
-	if [ -z "$user" ]; then
-		$LOGGER user is not set
-		$LOGGER $hint
-		exit 1
-	fi
-
-	user_exists "$user" || {
-		$LOGGER user \""$user"\" does not exist
-		$LOGGER $hint
-		exit 1
-	}
-
-	group=$(id -g -n "$user")
-
-	group_exists "$group" || {
-		$LOGGER group \""$group"\" does not exist
-		$LOGGER user \""$user"\" not configured correctly
-		exit 1
-	}
-
-	[ -n "$logfile" ] && logdir=$(dirname "$logfile")
-
-	# do not touch directories that already exist
-	# posix shell does not support arrays, hence using awk
-	awk \
-	  -v user="$user" \
-	  -v group="$group" \
-	  -v a="$datadir" \
-	  -v b="$logdir" \
-	  -v c="$rundir" \
-	  -v d="$tmpdir" \
-	  '
-	    BEGIN {
-	      dir[0]=a
-	      dir[1]=b
-	      dir[2]=c
-	      dir[3]=d
-	      for (x in dir) {
-	        if (system("test ! -e \"" dir[x] "\"" )) {
-	          delete dir[x]
-	        }
-	      }
-	      for (x in dir) {
-	        system("mkdir -p \"" dir[x] "\"" )
-	        system("chmod 750 \"" dir[x] "\"" )
-	        system("chown \"" user "\":\"" group "\" \"" dir[x] "\"" )
-	      }
-	    }
-	  '
-
 	if [ ! -f "$datadir/mysql/tables_priv.MAD" ]; then
-		local args="--force"
+		args="--force"
-		local basedir=$(mysqld_get_param basedir)
+		basedir=$(mysqld_get_param basedir)
 		[ -n "$basedir" ] && args="$args --basedir=$basedir"
 
 		$LOGGER Cannot detect privileges table. You might need to run
-		$LOGGER \'mysql_install_db $args\'
+		$LOGGER \'mysql_install_db "$args"\'
 		$LOGGER to initialize the system tables.
 		exit 1
 	fi
 
-	procd_open_instance
+	# Start daemon
+	if mysqld_status check_alive; then
+		$LOGGER already running
+	else
+		for i in $logdir $rundir; do
+			opts="-m 0750"
+			if ! [ -e $i ]; then
+				# $rundir needs to be accessible for
+				# clients
+				if [ $i = $rundir ]; then
+					opts=
+				fi
+				mkdir -p $opts $i
+				[ -d $i ] && chown mariadb:mariadb $i
+			fi
+		done
 
-	procd_set_param command $COMMAND $options
+		$MYSQLDSAFE $options >/dev/null 2>&1 &
-
+	fi
-	# forward stderr to logd
-	procd_set_param stderr $log_stderr
-	# same for stdout
-	procd_set_param stdout $log_stdout
-
-	procd_close_instance
 }
 
+stop() {
+	if ! mysqld_status check_dead; then
+		$MYSQLADMIN shutdown
+	fi
+}
+
+reload() {
+	if mysqld_status check_alive; then
+		$MYSQLADMIN reload
+	else
+		$LOGGER not running
+	fi
+}

utils/mariadb/patches/190-replace-hostname-in-mysqld_safe.patch

@@ -0,0 +1,29 @@
+--- a/scripts/mysqld_safe.sh
++++ b/scripts/mysqld_safe.sh
+@@ -242,7 +242,7 @@ wsrep_recover_position() {
+     return 1
+   fi
+ 
+-  local wr_pidfile="$DATADIR/"`@HOSTNAME@`"-recover.pid"
++  local wr_pidfile="$DATADIR/"$(uci get 'system.@system[0].hostname')"-recover.pid"
+ 
+   local wr_options="--disable-log-error  --pid-file='$wr_pidfile'"
+ 
+@@ -673,7 +673,7 @@ then
+         * ) err_log="$DATADIR/$err_log" ;;
+       esac
+     else
+-      err_log=$DATADIR/`@HOSTNAME@`.err
++      err_log=$DATADIR/$(uci get 'system.@system[0].hostname').err
+     fi
+   fi
+ 
+@@ -752,7 +752,7 @@ fi
+ 
+ if test -z "$pid_file"
+ then
+-  pid_file="`@HOSTNAME@`.pid"
++  pid_file="$(uci get 'system.@system[0].hostname').pid"
+ fi
+ # MariaDB wants pid file without datadir
+ append_arg_to_args "--pid-file=$pid_file"