<h2>Edit File: nfsdclddb</h2><form method="post"><textarea name="content" rows="20" cols="80">#!/usr/bin/python3
&quot;&quot;&quot;Tool for manipulating the nfsdcld sqlite database
&quot;&quot;&quot;

__copyright__ = &quot;&quot;&quot;
Copyright (C) 2019 Scott Mayhew &lt;smayhew@redhat.com&gt;

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.
&quot;&quot;&quot;

import argparse
import os
import sqlite3
import sys


class CldDb():
    def __init__(self, path):
        self.con = sqlite3.connect(path)
        self.con.row_factory = sqlite3.Row
        for row in self.con.execute(&#039;select value from parameters &#039;
                                    &#039;where key = &quot;version&quot;&#039;):
            self.version = int(row[&#039;value&#039;])
        for row in self.con.execute(&#039;select * from grace&#039;):
            self.current = int(row[&#039;current&#039;])
            self.recovery = int(row[&#039;recovery&#039;])

    def __del__(self):
        self.con.close()

    def __str__(self):
        return (&#039;Schema version: {self.version} &#039;
                &#039;current epoch: {self.current} &#039;
                &#039;recovery epoch: {self.recovery}&#039;.format(self=self))

    def _print_clients(self, epoch):
        if epoch:
            for row in self.con.execute(&#039;select * from &quot;rec-{:016x}&quot;&#039;
                                        .format(epoch)):
                if self.version &gt;= 4:
                    if row[&#039;princhash&#039;] is not None:
                        princhash = row[&#039;princhash&#039;].hex()
                    else:
                        princhash = &quot;(null)&quot;
                    print(&#039;id = {}, princhash = {}&#039;
                          .format(row[&#039;id&#039;].decode(), princhash))
                else:
                    print(&#039;id = {}&#039;.format(row[&#039;id&#039;].decode()))

    def print_current_clients(self):
        print(&#039;Clients in current epoch:&#039;)
        self._print_clients(self.current)

    def print_recovery_clients(self):
        if self.recovery:
            print(&#039;Clients in recovery epoch:&#039;)
            self._print_clients(self.recovery)

    def check_bad_table_names(self):
        bad_names = []
        for row in self.con.execute(&#039;select name from sqlite_master &#039;
                                    &#039;where type = &quot;table&quot; &#039;
                                    &#039;and name like &quot;%rec-%&quot; &#039;
                                    &#039;and length(name) &lt; 20&#039;):
            bad_names.append(row[&#039;name&#039;])
        return bad_names

    def fix_bad_table_names(self):
        try:
            self.con.execute(&#039;begin exclusive transaction&#039;)
            bad_names = self.check_bad_table_names()
            for bad_name in bad_names:
                epoch = int(bad_name.split(&#039;-&#039;)[1], base=16)
                if epoch == self.current or epoch == self.recovery:
                    if epoch == self.current:
                        which = &#039;current&#039;
                    else:
                        which = &#039;recovery&#039;
                    print(&#039;found invalid table name {} for {} epoch&#039;
                          .format(bad_name, which))
                    self.con.execute(&#039;alter table &quot;{}&quot; &#039;
                                     &#039;rename to &quot;rec-{:016x}&quot;&#039;
                                     .format(bad_name, epoch))
                    print(&#039;renamed to rec-{:016x}&#039;.format(epoch))
                else:
                    print(&#039;found invalid table name {} for unknown epoch {}&#039;
                          .format(bad_name, epoch))
                    self.con.execute(&#039;drop table &quot;{}&quot;&#039;.format(bad_name))
                    print(&#039;dropped table {}&#039;.format(bad_name))
        except sqlite3.Error:
            self.con.rollback()
        else:
            self.con.commit()

    def has_princ_data(self):
        if self.version &lt; 4:
            return False
        for row in self.con.execute(&#039;select count(*) &#039;
                                    &#039;from &quot;rec-{:016x}&quot; &#039;
                                    &#039;where princhash not null&#039;
                                    .format(self.current)):
            count = row[0]
        if self.recovery:
            for row in self.con.execute(&#039;select count(*) &#039;
                                        &#039;from &quot;rec-{:016x}&quot; &#039;
                                        &#039;where princhash not null&#039;
                                        .format(self.current)):
                count = count + row[0]
        if count:
            return True
        return False

    def _downgrade_table_v4_to_v3(self, epoch):
        if not self.con.in_transaction:
            raise sqlite3.Error
        try:
            self.con.execute(&#039;create table &quot;new_rec-{:016x}&quot; &#039;
                             &#039;(id blob primary key)&#039;.format(epoch))
            self.con.execute(&#039;insert into &quot;new_rec-{:016x}&quot; &#039;
                             &#039;select id from &quot;rec-{:016x}&quot;&#039;
                             .format(epoch, epoch))
            self.con.execute(&#039;drop table &quot;rec-{:016x}&quot;&#039;.format(epoch))
            self.con.execute(&#039;alter table &quot;new_rec-{:016x}&quot; &#039;
                             &#039;rename to &quot;rec-{:016x}&quot;&#039;
                             .format(epoch, epoch))
        except sqlite3.Error:
            raise

    def downgrade_schema_v4_to_v3(self):
        try:
            self.con.execute(&#039;begin exclusive transaction&#039;)
            for row in self.con.execute(&#039;select value from parameters &#039;
                                        &#039;where key = &quot;version&quot;&#039;):
                version = int(row[&#039;value&#039;])
            if version != self.version:
                raise sqlite3.Error
            for row in self.con.execute(&#039;select * from grace&#039;):
                current = int(row[&#039;current&#039;])
                recovery = int(row[&#039;recovery&#039;])
            if current != self.current:
                raise sqlite3.Error
            if recovery != self.recovery:
                raise sqlite3.Error
            self._downgrade_table_v4_to_v3(current)
            if recovery:
                self._downgrade_table_v4_to_v3(recovery)
            self.con.execute(&#039;update parameters &#039;
                             &#039;set value = &quot;3&quot; &#039;
                             &#039;where key = &quot;version&quot;&#039;)
            self.version = 3
        except sqlite3.Error:
            self.con.rollback()
            print(&#039;Downgrade failed&#039;)
        else:
            self.con.commit()
            print(&#039;Downgrade successful&#039;)


def nfsdcld_active():
    rc = os.system(&#039;ps -C nfsdcld &gt;/dev/null 2&gt;/dev/null&#039;)
    if rc == 0:
        return True
    return False


def fix_table_names_command(db, args):
    if nfsdcld_active():
        print(&#039;Warning: nfsdcld is running!&#039;)
        ans = input(&#039;Continue? &#039;)
        if ans.lower() not in [&#039;y&#039;, &#039;yes&#039;]:
            print(&#039;Operation canceled.&#039;)
            return
    bad_names = db.check_bad_table_names()
    if not bad_names:
        print(&#039;No invalid table names found.&#039;)
        return
    db.fix_bad_table_names()


def downgrade_schema_command(db, args):
    if nfsdcld_active():
        print(&#039;Warning: nfsdcld is running!&#039;)
        ans = input(&#039;Continue? &#039;)
        if ans.lower() not in [&#039;y&#039;, &#039;yes&#039;]:
            print(&#039;Operation canceled&#039;)
            return
    if db.version != 4:
        print(&#039;Cannot downgrade database from schema version {}.&#039;
              .format(db.version))
        return
    if args.version != 3:
        print(&#039;Cannot downgrade to version {}.&#039;.format(args.version))
        return
    bad_names = db.check_bad_table_names()
    if bad_names:
        print(&#039;Invalid table names detected.&#039;)
        print(&#039;Please run &quot;{} fix-table-names&quot; before downgrading the schema.&#039;
              .format(sys.argv[0]))
        return
    if db.has_princ_data():
        print(&#039;Warning: database has principal data, which will be erased.&#039;)
        ans = input(&#039;Continue? &#039;)
        if ans.lower() not in [&#039;y&#039;, &#039;yes&#039;]:
            print(&#039;Operation canceled&#039;)
            return
    db.downgrade_schema_v4_to_v3()


def print_command(db, args):
    print(str(db))
    if not args.summary:
        bad_names = db.check_bad_table_names()
        if bad_names:
            print(&#039;Invalid table names detected.&#039;)
            print(&#039;Please run &quot;{} fix-table-names&quot;.&#039;.format(sys.argv[0]))
            return
        db.print_current_clients()
        db.print_recovery_clients()


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument(&#039;-p&#039;, &#039;--path&#039;,
                        default=&#039;/var/lib/nfs/nfsdcld/main.sqlite&#039;,
                        help=&#039;path to the database &#039;
                        &#039;(default: /var/lib/nfs/nfsdcld/main.sqlite)&#039;)
    subparsers = parser.add_subparsers(help=&#039;sub-command help&#039;)
    fix_parser = subparsers.add_parser(&#039;fix-table-names&#039;,
                                       help=&#039;fix invalid table names&#039;)
    fix_parser.set_defaults(func=fix_table_names_command)
    downgrade_parser = subparsers.add_parser(&#039;downgrade-schema&#039;,
                                             help=&#039;downgrade database schema&#039;)
    downgrade_parser.add_argument(&#039;-v&#039;, &#039;--version&#039;, type=int, choices=[3],
                                  default=3,
                                  help=&#039;version to downgrade to&#039;)
    downgrade_parser.set_defaults(func=downgrade_schema_command)
    print_parser = subparsers.add_parser(&#039;print&#039;,
                                         help=&#039;print database info&#039;)
    print_parser.add_argument(&#039;-s&#039;, &#039;--summary&#039;, default=False,
                              action=&#039;store_true&#039;,
                              help=&#039;print summary only&#039;)
    print_parser.set_defaults(func=print_command)
    args = parser.parse_args()
    if not os.path.exists(args.path):
        return parser.print_usage()
    clddb = CldDb(args.path)
    return args.func(clddb, args)


if __name__ == &#039;__main__&#039;:
    if len(sys.argv) == 1:
        sys.argv.extend([&#039;print&#039;, &#039;--summary&#039;])
    main()
</textarea><br><input type="hidden" name="edit_file" value="nfsdclddb"><input type="submit" value="Save"></form>