#!/bin/sh

# This script creates the mysql data directory during first service start.

# In subsequent starts, it does nothing much.

# extract value of a MySQL option from config files

# Usage: get_mysql_option SECTION VARNAME DEFAULT

# result is returned in $result

# We use my_print_defaults which prints all options from multiple files,

# with the more specific ones later; hence take the last match.

get_mysql_option(){

        if [ $# -ne 3 ] ; then

          echo "get_mysql_option requires 3 arguments: section option default_value"

          return

        fi

        result=`/usr/bin/my_print_defaults "$1" | sed -n "s/^--$2=//p" | tail -n 1`

        if [ -z "$result" ]; then

            # if not found, use the default value

            result="$3"

        fi

}

# Defaults here had better match what mysqld_safe will default to

get_mysql_option mysqld datadir "/var/lib/mysql"

datadir="$result"

get_mysql_option mysqld_safe log-error "/var/log/mariadb/mariadb.log"

errlogfile="$result"

get_mysql_option mysqld socket "$datadir/mysql.sock"

socketfile="$result"

# Absorb configuration settings from the specified systemd service file,

# or the default "mysqld" service if not specified

SERVICE_NAME="$1"

if [ x"$SERVICE_NAME" = x ]

then

    SERVICE_NAME=mysqld.service

fi

myuser=`systemctl show -p User "${SERVICE_NAME}" |

  sed 's/^User=//'`

if [ x"$myuser" = x ]

then

    myuser=mysql

fi

mygroup=`systemctl show -p Group "${SERVICE_NAME}" |

  sed 's/^Group=//'`

if [ x"$mygroup" = x ]

then

    mygroup=mysql

fi

# Set up the errlogfile with appropriate permissions

if [ ! -e "$errlogfile" -a ! -h "$errlogfile" -a x$(dirname "$errlogfile") = "x/var/log" ]; then

    case $(basename "$errlogfile") in

        mysql*.log|mariadb*.log) install /dev/null -m0640 -o$myuser -g$mygroup "$errlogfile" ;;

        *) ;;

    esac

else

    # Provide some advice if the log file cannot be created by this script

    errlogdir=$(dirname "$errlogfile")

    if ! [ -d "$errlogdir" ] ; then

        echo "The directory $errlogdir does not exist."

        exit 1

    elif [ -e "$errlogfile" -a ! -w "$errlogfile" ] ; then

        echo "The log file $errlogfile cannot be written, please, fix its permissions."

        echo "The daemon will be run under $myuser:$mygroup"

        exit 1

    fi

fi

# We check if there is already a process using the socket file,

# since otherwise this systemd service file could report false

# positive result when starting and mysqld_safe could remove

# a socket file, which actually uses a different daemon.

if fuser "$socketfile" &>/dev/null ; then

    echo "Socket file $socketfile exists." >&2

    echo "Is another MySQL daemon already running with the same unix socket?" >&2

    exit 1

fi

export LC_ALL=C

# Returns content of the specified directory

# If listing files fails, fake-file is returned so which means

# we'll behave like there was some data initialized

# Some files or directories are fine to be there, so those are

# explicitly removed from the listing

# @param <dir> datadir

list_datadir ()

{

    ( ls -1A "$1" 2>/dev/null || echo "fake-file" ) | grep -v \

    -e '^lost+found$' \

    -e '\.err$' \

    -e '^.bash_history$'

}

# Checks whether datadir should be initialized

# @param <dir> datadir

should_initialize ()

{

    test -z "$(list_datadir "$1")"

}

# Make the data directory if doesn't exist or empty

if should_initialize "$datadir" ; then

    # First, make sure $datadir is there with correct permissions

    # (note: if it's not, and we're not root, this'll fail ...)

    if [ ! -e "$datadir" -a ! -h "$datadir" ]

    then

        mkdir -p "$datadir" || exit 1

    fi

    chown "$myuser:$mygroup" "$datadir"

    chmod 0755 "$datadir"

    [ -x /sbin/restorecon ] && /sbin/restorecon "$datadir"

    # Now create the database

    echo "Initializing MariaDB database"

    # Avoiding deletion of files not created by mysql_install_db is

    # guarded by time check and sleep should help work-arounded

    # potential issues on systems with 1 second resolution timestamps

    # https://bugzilla.redhat.com/show_bug.cgi?id=1335849#c19

    INITDB_TIMESTAMP=`LANG=C date -u`

    sleep 1

    /usr/bin/mysql_install_db --rpm --datadir="$datadir" --user="$myuser"

    ret=$?

    if [ $ret -ne 0 ] ; then

        echo "Initialization of MariaDB database failed." >&2

        echo "Perhaps @sysconfdir@/my.cnf is misconfigured or there is some problem with permissions of $datadir." >&2

        # Clean up any partially-created database files

        if [ ! -e "$datadir/mysql/user.frm" ] && [ -d "$datadir" ] ; then

            echo "Initialization of MariaDB database was not finished successfully." >&2

            echo "Files created so far will be removed." >&2

            find "$datadir" -mindepth 1 -maxdepth 1 -newermt "$INITDB_TIMESTAMP" \

                 -not -name "lost+found" -exec rm -rf {} +

            if [ $? -ne 0 ] ; then

                echo "Removing of created files was not successfull." >&2

                echo "Please, clean directory $datadir manually." >&2

            fi

        else

            echo "However, part of data has been initialized and those will not be removed." >&2

            echo "Please, clean directory $datadir manually." >&2

        fi

        exit $ret

    fi

else

    if [ -d "$datadir/mysql/" ] ; then

        # mysql dir exists, it seems data are initialized properly

        echo "Database MariaDB is probably initialized in $datadir already, nothing is done."

        echo "If this is not the case, make sure the $datadir is empty before running `basename $0`."

    else

        # if the directory is not empty but mysql/ directory is missing, then

        # print error and let user to initialize manually or empty the directory

        echo "Database MariaDB is not initialized, but the directory $datadir is not empty, so initialization cannot be done."

        echo "Make sure the $datadir is empty before running `basename $0`."

        exit 1

    fi

fi

exit 0