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#!/usr/bonsaitools/bin/perl -w
# -*- Mode: perl; indent-tabs-mode: nil -*-
#
# The contents of this file are subject to the Mozilla Public
# License Version 1.1 (the "License"); you may not use this file
# except in compliance with the License. You may obtain a copy of
# the License at http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS
# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
# implied. See the License for the specific language governing
# rights and limitations under the License.
#
# The Original Code is the Bugzilla Bug Tracking System.
#
# The Initial Developer of the Original Code is Netscape Communications
# Corporation. Portions created by Netscape are
# Copyright (C) 1998 Netscape Communications Corporation. All
# Rights Reserved.
#
# Contributor(s): Terry Weissman <terry@mozilla.org>
# David Gardiner <david.gardiner@unisa.edu.au>
use diagnostics;
use strict;
require "globals.pl";
require "defparams.pl";
# Shut up misguided -w warnings about "used only once". "use vars" just
# doesn't work for me.
sub sillyness {
my $zz;
open SAVEOUT,">/dev/null";
$zz = $::db;
$zz = $::dbwritesallowed;
}
my $verbose = 0;
my $syncall = 0;
sub Usage {
print "Usage: syncshadowdb [-v] [-syncall]\n";
exit;
}
foreach my $opt (@ARGV) {
if ($opt eq '-v') {
$verbose = 1;
} elsif ($opt eq '-syncall') {
$syncall = 1;
$verbose = 1;
} else {
Usage();
}
}
$| = 1;
my $logtostderr = 0;
sub Verbose ($) {
my ($str) = (@_);
if ($verbose) {
if ($logtostderr) {
print STDERR $str, "\n";
} else {
print $str, "\n";
}
}
}
my $db_name = "bugs";
require "localconfig";
if (!Param("shadowdb")) {
Verbose("We don't have shadow databases turned on; no syncing performed.");
exit;
}
my $wasusing = Param("queryagainstshadowdb");
$::param{'queryagainstshadowdb'} = 1; # Force us to be able to use the
# shadowdb, even if other processes
# are not supposed to.
ConnectToDatabase(1);
Verbose("Acquiring lock");
if ( $syncall == 1) {
SendSQL("SELECT GET_LOCK('synclock', 2700)");
} else {
SendSQL("SELECT GET_LOCK('synclock', 1)");
}
if (!FetchOneColumn()) {
Verbose("Couldn't get the lock to do the shadow database syncing.");
exit;
}
my $shadowtable = "$db_name.shadowlog";
if (!$syncall) {
Verbose("Looking for requests to sync the whole database.");
SendSQL("SELECT id FROM $shadowtable " .
"WHERE reflected = 0 AND command = 'SYNCUP'");
if (FetchOneColumn()) {
$syncall = 1;
}
}
if ($syncall) {
Verbose("Syncing up the shadow database by copying entire database in.");
if ($wasusing) {
$::param{'queryagainstshadowdb'} = 0;
WriteParams();
Verbose("Disabled reading from the shadowdb. Sleeping 10 seconds to let other procs catch up.");
sleep(10);
$::param{'queryagainstshadowdb'} = 1;
}
my @tables;
SendSQL("SHOW TABLES");
my $query = "";
while (MoreSQLData()) {
my $table = FetchOneColumn();
push(@tables, $table);
if ($query) {
$query .= ", $table WRITE";
} else {
$query = "LOCK TABLES $table WRITE";
}
}
if (@tables) {
Verbose("Locking entire shadow database");
SendSQL($query);
foreach my $table (@tables) {
Verbose("Dropping old shadow table $table");
SendSQL("DROP TABLE $table");
}
SendSQL("UNLOCK TABLES");
}
# Carefully lock the whole real database for reading, except for the
# shadowlog table, which we lock for writing. Then dump everything
# into the shadowdb database. Then mark everything in the shadowlog
# as reflected. Only then unlock everything. This sequence causes
# us to be sure not to miss anything or get something twice.
SendSQL("USE $db_name");
SendSQL("SHOW TABLES");
@tables = ();
$query = "LOCK TABLES shadowlog WRITE";
while (MoreSQLData()) {
my $table = FetchOneColumn();
if ($table ne "shadowlog") {
$query .= ", $table READ";
push(@tables, $table);
}
}
Verbose("Locking entire database");
SendSQL($query);
my $tempfile = "data/tmpsyncshadow.$$";
Verbose("Dumping database to a temp file ($tempfile).");
open SAVEOUT, ">&STDOUT"; # stash the original output stream
open STDOUT, ">$tempfile"; # redirect to file
select STDOUT; $| = 1; # disable buffering
system("mysqldump","-l","-e",$db_name,@tables);
open STDOUT, ">&SAVEOUT"; # redirect back to original stream
Verbose("Restoring from tempfile into shadowdb");
my $extra = "";
if ($verbose) {
$extra = "-v";
}
open(MYSQL, "cat $tempfile | mysql $extra " .
Param("shadowdb") . "|") || die "Couldn't do db copy";
my $count = 0;
while (<MYSQL>) {
print ".";
$count++;
if ($count % 70 == 0) {
print "\n";
}
}
close(MYSQL);
unlink($tempfile);
Verbose("");
$::dbwritesallowed = 1;
# SendSQL("UPDATE shadowlog SET reflected = 1 WHERE reflected = 0", 1);
SendSQL("DELETE FROM shadowlog", 1);
SendSQL("UNLOCK TABLES");
if ($wasusing) {
Verbose("Reenabling other processes to read from the shadow db");
$::param{'queryagainstshadowdb'} = 1;
WriteParams();
}
Verbose("OK, done.");
}
Verbose("Looking for commands to execute.");
$::dbwritesallowed = 1;
# Make us low priority, to not block anyone who is trying to actually use
# the shadowdb. Note that this is carefully coded to ignore errors; we want
# to keep going even on older mysqld's that don't have the
# SQL_LOW_PRIORITY_UPDATES option.
$::db->do("SET OPTION SQL_LOW_PRIORITY_UPDATES = 1");
while (1) {
SendSQL("SELECT id, command FROM $shadowtable WHERE reflected = 0 " .
"ORDER BY id LIMIT 1");
my ($id, $command) = (FetchSQLData());
if (!$id) {
last;
}
Verbose("Executing command in shadow db: $command");
SendSQL($command, 1);
SendSQL("UPDATE $shadowtable SET reflected = 1 WHERE id = $id", 1);
}
Verbose("Releasing lock.");
SendSQL("SELECT RELEASE_LOCK('synclock')");
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