#!/bin/sh
# (C) 2006, 2007, 2008 Gluster Inc. <http://www.gluster.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public
# License along with this program; if not, write to the Free
# Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
# Boston, MA 02110-1301 USA

_init ()
{
    # log level definitions
    LOG_NONE=NONE;
    LOG_CRITICAL=CRITICAL;
    LOG_ERROR=ERROR;
    LOG_WARNING=WARNING;
    LOG_INFO=INFO
    LOG_DEBUG=DEBUG;
    LOG_TRACE=TRACE;

    prefix="@prefix@";
    exec_prefix=@exec_prefix@;
    cmd_line=$(echo "@sbindir@/glusterfs");

    case `uname -s` in
    NetBSD)
        getinode="stat -f %i"
        getdev="stat -f %d"
        lgetinode="${getinode} -L"
        lgetdev="${getdev} -L"

        mounttab=/proc/mounts
        ;;
    Linux)
        getinode="stat -c %i $i"
        getdev="stat -c %d $d"
        lgetinode="${getinode} -L"
        lgetdev="${getdev} -L"

        mounttab=/etc/mtab
        ;;
    esac

    UPDATEDBCONF=/etc/updatedb.conf
    LD_LIBRARY_PATH=@libdir@:${LD_LIBRARY_PATH}
    export LD_LIBRARY_PATH
}

start_glusterfs ()
{
    # lets the comparsion be case insensitive for all strings

    if [ -n "$log_level_str" ]; then
	case "$( echo $log_level_str | tr '[a-z]' '[A-Z]')" in
	    "ERROR")
		log_level=$LOG_ERROR;
		;;
            "INFO")
                log_level=$LOG_INFO
                ;;
	    "DEBUG")
		log_level=$LOG_DEBUG;
		;;
	    "CRITICAL")
		log_level=$LOG_CRITICAL;
		;;
	    "WARNING")
		log_level=$LOG_WARNING;
		;;
	    "TRACE")
		log_level=$LOG_TRACE;
		;;
	    "NONE")
		log_level=$LOG_NONE;
		;;
	    *)
		echo "invalid log level $log_level_str, using INFO";
		log_level=$LOG_INFO;
		;;
	esac
    fi
    if [ -n "$log_level" ]; then
        cmd_line=$(echo "$cmd_line --log-level=$log_level");
    fi

    if [ -n "$read_only" ]; then
	cmd_line=$(echo "$cmd_line --read-only");
    fi

    if [ -n "$acl" ]; then
	cmd_line=$(echo "$cmd_line --acl");
    fi

    if [ -n "$selinux" ]; then
	cmd_line=$(echo "$cmd_line --selinux");
    fi

    if [ -n "$worm" ]; then
        cmd_line=$(echo "$cmd_line --worm");
    fi

    if [ -n "$log_file" ]; then
	cmd_line=$(echo "$cmd_line --log-file=$log_file");
    fi

    if [ -n "$volfile_check" ]; then
	cmd_line=$(echo "$cmd_line --volfile-check");
    fi

    if [ -n "$direct_io_mode" ]; then
	cmd_line=$(echo "$cmd_line --direct-io-mode=$direct_io_mode");
    fi

    if [ -n "$volume_name" ]; then
        cmd_line=$(echo "$cmd_line --volume-name=$volume_name");
    fi

    # for rdma volume, we have to fetch volfile with '.rdma' added
    # to volume name, so that it fetches the right client vol file
    volume_id_rdma="";

    if [ -z "$volfile_loc" ]; then
        if  [ -n "$server_ip" ]; then
            if [ -n "$server_port" ]; then
                cmd_line=$(echo "$cmd_line --volfile-server-port=$server_port");
            fi
	    if [ -n "$transport" ]; then
                cmd_line=$(echo "$cmd_line --volfile-server-transport=$transport");
                if [ "$transport" = "rdma" ]; then
                    volume_id_rdma=".rdma";
                fi
            fi
            if [ -n "$volume_id" ]; then
                if [ -n "$volume_id_rdma" ]; then
                    volume_id="$volume_id$volume_id_rdma";
                fi
                cmd_line=$(echo "$cmd_line --volfile-id=$volume_id");
            fi

            if [ -n "$backupvolfile_server" ]; then
                cmd_line1=$(echo "$cmd_line --volfile-server=$backupvolfile_server");
            fi
            if [ -n "$volfile_max_fetch_attempts" ]; then
                cmd_line=$(echo "$cmd_line --volfile-max-fetch-attempts=$volfile_max_fetch_attempts");
            fi
	    cmd_line=$(echo "$cmd_line --volfile-server=$server_ip");
        fi
    else
        cmd_line=$(echo "$cmd_line --volfile=$volfile_loc");
    fi

    cmd_line=$(echo "$cmd_line $mount_point");
    err=0;
    $cmd_line;


    inode=$( ${getinode} $mount_point 2>/dev/null);

    # this is required if the stat returns error
    if [ -z "$inode" ]; then
        inode="0";
    fi

    # retry the failover
    # if [ $? != "0" ]; then # <--- TODO: Once glusterfs returns proper error code, change it.
    if [ $inode -ne 1 ]; then
        err=1;
        if [ -n "$cmd_line1" ]; then
            cmd_line1=$(echo "$cmd_line1 $mount_point");
            $cmd_line1;
            err=0;

            inode=$( ${getinode} $mount_point 2>/dev/null);
            # this is required if the stat returns error
            if [ -z "$inode" ]; then
                inode="0";
            fi
            if [ $inode -ne 1 ]; then
                err=1;
            fi
        fi
    fi

    if [ $err -eq "1" ]; then
            echo "Mount failed. Please check the log file for more details."
            umount $mount_point > /dev/null 2>&1;
            exit 1;
    fi
}

usage ()
{

echo "Usage:  mount.glusterfs <volumeserver>:<volumeid/volumeport> -o <options> <mountpoint>
Options:
man 8 mount.glusterfs

To display the version number of the mount helper:
mount.glusterfs --version"

}

# check for recursive mounts. i.e, mounting over an existing brick
check_recursive_mount ()
{
    if [ $2 = "/" ]; then
        echo Cannot mount over root;
        exit 2;
    fi
    # GFID check first
    # remove trailing / from mount point
    mnt_dir=${2%/};

    export PATH;
    # check whether getfattr exists
    which getfattr > /dev/null 2>&1;
    if [ $? -ne 0 ]; then
        return;
    fi

    getfattr -n trusted.gfid $mnt_dir 2>/dev/null | grep -iq "trusted.gfid=";
    if [ $? -eq 0 ]; then
        echo "ERROR: $mnt_dir is in use as a brick of a gluster volume";
        exit 2;
    fi

    # check if the mount point is a brick's parent directory
    GLUSTERD_WORKDIR="/var/lib/glusterd";

    ls -L "$GLUSTERD_WORKDIR"/vols/*/bricks/* > /dev/null 2>&1;
    if [ $? -ne 0 ]; then
        return;
    fi

    brick_path=`grep ^path "$GLUSTERD_WORKDIR"/vols/*/bricks/* | cut -d "=" -f 2`;
    root_inode=`${lgetinode} /`;
    root_dev=`${lgetdev} /`;
    mnt_inode=`${lgetinode} $mnt_dir`;
    mnt_dev=`${lgetdev} $mnt_dir`;
    for brick in "$brick_path";
    do
        # evaluate brick path to see if this is local, if non-local, skip iteration
        ls $brick > /dev/null 2>&1;
        if [ $? -ne 0 ]; then
            continue;
        fi
        getfattr -n trusted.gfid "$brick" 2>/dev/null | grep -iq "trusted.gfid=";
        if [ $? -ne 0 ]; then
            continue;
        else
            # brick is local
            while [ 1 ];
            do
                tmp_brick="$brick";
                brick="$brick"/..;
                brick_dev=`${lgetdev} $brick`;
                brick_inode=`${lgetinode} $brick`;
                if [ "$mnt_inode" -eq "$brick_inode" -a "$mnt_dev" -eq "$brick_dev" ]; then
                    echo ERROR: $mnt_dir is a parent of the brick $tmp_brick;
                    exit 2;
                fi
                [ "$root_inode" -ne "$brick_inode" -o "$root_dev" -ne "$brick_dev" ] || break;
            done;
        fi
    done;
}

main ()
{
    helper=$(echo "$@" | sed -n 's/.*\--[ ]*\([^ ]*\).*/\1/p');

    in_opt="no"
    pos_args=0
    for opt in "$@"; do
        if [ "$in_opt" = "yes" ]; then
            for pair in $(echo "$opt" | tr "," " "); do
                # Handle options without values.
                case "$pair" in
                    "ro")       read_only=1 ;;
                    "acl")      acl=1 ;;
                    "selinux")  selinux=1 ;;
                    "worm")     worm=1 ;;
                    # "mount -t glusterfs" sends this, but it's useless.
                    "rw")       ;;
                    *)
                        key=$(echo "$pair" | cut -f1 -d'=');
                        value=$(echo "$pair" | cut -f2- -d'=');

                        # Handle options with values.
                        case "$key" in
                            "log-level")        log_level_str=$value ;;
                            "log-file")         log_file=$value ;;
                            "transport")        transport=$value ;;
                            "direct-io-mode")   direct_io_mode=$value ;;
                            "volume-name")      volume_name=$value ;;
                            "volume-id")        volume_id=$value ;;
                            "volfile-check")    volfile_check=$value ;;
                            "server-port")      server_port=$value ;;
                            "fetch-attempts")
                                volfile_max_fetch_attempts=$value ;;
                            "backupvolfile-server")
                                backupvolfile_server=$value ;;
                            *) echo "unknown option $key (ignored)" ;;
                        esac
                esac
            done
            in_opt="no"
        elif [ "$opt" = "-o" ]; then
            in_opt="yes"
        else
            case $pos_args in
                0)      volfile_loc=$opt ;;
                1)      mount_point=$opt ;;
                *)      echo "extra arguments at end (ignored)" ;;
            esac
            pos_args=$((pos_args+1))
        fi
    done
    if [ $in_opt = "yes" -o $pos_args -lt 2 ]; then
        usage
        exit 1
    fi

    [ -r "$volfile_loc" ] || {
        server_ip=$(echo "$volfile_loc" | sed -n 's/\([a-zA-Z0-9:.\-]*\):.*/\1/p');
        test_str=$(echo "$volfile_loc" | sed -n 's/.*:\([^ ]*\).*/\1/p');
        [ -n "$test_str" ] && {
            volume_id="$test_str";
        }
	volfile_loc="";
    }

    #
    [ -n "$helper" ] && {
        cmd_line=$(echo "$cmd_line --$helper");
        exec $cmd_line;
        exit 0;
    }

    # No need to do a ! -d test, it is taken care while initializing the
    # variable mount_point
    [ -z "$mount_point" -o ! -d "$mount_point" ] && {
        echo "ERROR: Mount point does not exist."
        usage;
        exit 0;
    }

    # Simple check to avoid multiple identical mounts
    if grep -q " ${mount_point}.*fuse" $mounttab; then
        echo -n "$0: according to mtab, GlusterFS is already mounted on "
        echo "$mount_point"
        exit 0;
    fi

    check_recursive_mount "$@";

    # Append fuse.glusterfs to PRUNEFS variable in updatedb.conf(5). updatedb(8)
    # should not index files under GlusterFS, indexing will slow down GlusteFS
    # if the filesystem is several TB in size.
    test -f $UPDATEDBCONF && {
        if ! grep -q 'glusterfs' $UPDATEDBCONF; then
            sed 's/\(PRUNEFS.*\)"/\1 fuse.glusterfs"/' $UPDATEDBCONF \
                > ${UPDATEDBCONF}.bak
            mv -f ${UPDATEDBCONF}.bak $UPDATEDBCONF
        fi
    }

    start_glusterfs;
}

_init "$@" && main "$@";