Deliantra-Client/DC/DB.pm

=head1 NAME

CFPlus::DB - async. database and filesystem access for cfplus

=head1 SYNOPSIS

 use CFPlus::DB;

=head1 DESCRIPTION

=over 4

=cut

package CFPlus::DB;

use strict;
use utf8;

use Carp ();
use Storable ();
use Config;
use Event ();

use CFPlus;

our $DB_HOME = "$Crossfire::VARDIR/cfplus-$BerkeleyDB::db_version-$Config{archname}";

sub path_of_res($) {
   utf8::downgrade $_[0]; # bug in unpack "H*"
   "$DB_HOME/res-data-" . unpack "H*", $_[0]
}

sub sync {
   # for debugging
   #CFPlus::DB::Server::req (sync => sub { });
   CFPlus::DB::Server::sync ();
}

sub exists($$$) {
   CFPlus::DB::Server::req (exists => @_);
}

sub get($$$) {
   CFPlus::DB::Server::req (get => @_);
}

sub put($$$$) {
   CFPlus::DB::Server::req (put => @_);
}

sub unlink($$) {
   CFPlus::DB::Server::req (unlink => @_);
}

sub read_file($$) {
   CFPlus::DB::Server::req (read_file => @_);
}

sub write_file($$$) {
   CFPlus::DB::Server::req (write_file => @_);
}

sub prefetch_file($$$) {
   CFPlus::DB::Server::req (prefetch_file => @_);
}

sub logprint($$$) {
   CFPlus::DB::Server::req (logprint => @_);
}

our $tilemap;

sub get_tile_id_sync($) {
   my ($hash) = @_;

   # fetch the full face table first
   unless ($tilemap) {
      CFPlus::DB::Server::req (table => facemap => sub { $tilemap = $_[0] });
      sync;
   }

   $tilemap->{$hash} ||= do {
      my $id;
      CFPlus::DB::Server::req (get_tile_id => $hash, sub { $id = $_[0] });
      sync;
      $id
   }
}

package CFPlus::DB::Server;

use strict;

use Fcntl;
use BerkeleyDB;

our $DB_ENV;
our $DB_STATE;
our %DB_TABLE;

sub open_db {
   mkdir $DB_HOME, 0777;
   my $recover = $BerkeleyDB::db_version >= 4.4 
                 ? eval "DB_REGISTER | DB_RECOVER"
                 : 0;

   $DB_ENV = new BerkeleyDB::Env
                    -Home => $DB_HOME,
                    -Cachesize => 8_000_000,
                    -ErrFile => "$DB_HOME/errorlog.txt",
#                 -ErrPrefix => "DATABASE",
                    -Verbose => 1,
                    -Flags => DB_CREATE | DB_RECOVER | DB_INIT_MPOOL | DB_INIT_LOCK | DB_INIT_TXN | $recover,
                    -SetFlags => DB_AUTO_COMMIT | DB_LOG_AUTOREMOVE | DB_TXN_WRITE_NOSYNC,
                       or die "unable to create/open database home $DB_HOME: $BerkeleyDB::Error";

   1
}

sub table($) {
   $DB_TABLE{$_[0]} ||= do {
      my ($table) = @_;

      $table =~ s/([^a-zA-Z0-9_\-])/sprintf "=%x=", ord $1/ge;

      new BerkeleyDB::Btree
         -Env      => $DB_ENV,
         -Filename => $table,
#      -Filename => "database",
#      -Subname  => $table,
         -Property => DB_CHKSUM,
         -Flags    => DB_AUTO_COMMIT | DB_CREATE | DB_UPGRADE,
            or die "unable to create/open database table $_[0]: $BerkeleyDB::Error"
   }
}

our %CB;
our $FH;
our $ID = "aaa0";
our ($fh_r_watcher, $fh_w_watcher);
our $sync_timer;
our $write_buf;
our $read_buf;

our $SYNC = Event->idle (min => 120, max => 180, parked => 1, cb => sub {
   CFPlus::DB::Server::req (sync => sub { });
   $_[0]->w->stop;
});

sub fh_write {
   my $len = syswrite $FH, $write_buf;

   substr $write_buf, 0, $len, "";

   $fh_w_watcher->stop
      unless length $write_buf;
}

sub fh_read {
   my $status = sysread $FH, $read_buf, 16384, length $read_buf;

   die "FATAL: database process died\n"
      if $status == 0 && defined $status;

   while () {
      return if 4 > length $read_buf;
      my $len = unpack "N", $read_buf;

      return if $len + 4 > length $read_buf;

      substr $read_buf, 0, 4, "";
      my $res = Storable::thaw substr $read_buf, 0, $len, "";

      my ($id, @args) = @$res;
      (delete $CB{$id})->(@args);
   }
}

sub sync {
   # biggest mess evarr
   my $fds; (vec $fds, fileno $FH, 1) =  1;

   while (1 < scalar keys %CB) {
      my $r = $fds;
      my $w = length $write_buf ? $fds : undef;
      select $r, $w, undef, undef;

      fh_write if vec $w, fileno $FH, 1;
      fh_read  if vec $r, fileno $FH, 1;
   }
}

sub req {
   my ($type, @args) = @_;
   my $cb = pop @args;

   my $id = ++$ID;
   $write_buf .= pack "N/a*", Storable::freeze [$id, $type, @args];
   $CB{$id} = $cb;

   $fh_w_watcher->start;
   $SYNC->start;
}

sub do_sync {
   $DB_ENV->txn_checkpoint (0, 0, 0);
   ()
}

sub do_exists {
   my ($db, $key) = @_;

   utf8::downgrade $key;
   my $data;
   (table $db)->db_get ($key, $data) == 0
      ? length $data
      : ()
}

sub do_get {
   my ($db, $key) = @_;

   utf8::downgrade $key;
   my $data;
   (table $db)->db_get ($key, $data) == 0
      ? $data
      : ()
}

sub do_put {
   my ($db, $key, $data) = @_;

   utf8::downgrade $key;
   utf8::downgrade $data;
   (table $db)->db_put ($key => $data)
}

sub do_table {
   my ($db) = @_;

   $db = table $db;

   my $cursor = $db->db_cursor;
   my %kv;
   my ($k, $v);
   $kv{$k} = $v while $cursor->c_get ($k, $v, BerkeleyDB::DB_NEXT) == 0;

   \%kv
}

sub do_get_tile_id {
   my ($hash) = @_;

   my $id;
   my $table = table "facemap";

   return $id
      if $table->db_get ($hash, $id) == 0;

   for (1..100) {
      my $txn = $DB_ENV->txn_begin;
      my $status = $table->db_get (id => $id);
      if ($status == 0 || $status == BerkeleyDB::DB_NOTFOUND) {
         $id = ($id || 64) + 1;
         if ($table->db_put (id => $id) == 0
             && $table->db_put ($hash => $id) == 0) {
            $txn->txn_commit;

            return $id;
         }
      }
      $txn->txn_abort;
      select undef, undef, undef, 0.01 * rand;
   }

   die "maximum number of transaction retries reached - database problems?";
}

sub do_unlink {
   unlink $_[0];
}

sub do_read_file {
   my ($path) = @_;

   utf8::downgrade $path;
   open my $fh, "<:raw", $path
      or return;
   sysread $fh, my $buf, -s $fh;

   $buf
}

sub do_write_file {
   my ($path, $data) = @_;

   utf8::downgrade $path;
   utf8::downgrade $data;
   open my $fh, ">:raw", $path
      or return;
   syswrite $fh, $data;
   close $fh;

   1
}

sub do_prefetch_file {
   my ($path, $size) = @_;

   utf8::downgrade $path;
   open my $fh, "<:raw", $path
      or return;
   sysread $fh, my $buf, $size;

   1
}

our %LOG_FH;

sub do_logprint {
   my ($path, $line) = @_;

   $LOG_FH{$path} ||= do {
      open my $fh, ">>:utf8", $path
         or warn "Couldn't open logfile $path: $!";

      $fh->autoflush (1);

      $fh
   };

   my ($sec, $min, $hour, $mday, $mon, $year) = localtime time;

   my $ts = sprintf "%04d-%02d-%02d %02d:%02d:%02d",
               $year + 1900, $mon + 1, $mday, $hour, $min, $sec;

   print { $LOG_FH{$path} } "$ts $line\n"
}

sub run {
   ($FH, my $fh) = CFPlus::socketpipe;

   my $oldfh = select $FH; $| = 1; select $oldfh;
   my $oldfh = select $fh; $| = 1; select $oldfh;

   my $pid = fork;
   
   if (defined $pid && !$pid) {
      local $SIG{QUIT};
      local $SIG{__DIE__};
      local $SIG{__WARN__};
      eval {
         close $FH;

         unless (eval { open_db }) {
            eval { File::Path::rmtree $DB_HOME };
            open_db;
         }

         while () {
            4 == read $fh, my $len, 4
               or last;
            $len = unpack "N", $len;
            $len == read $fh, my $req, $len
               or die "unexpected eof while reading request";

            $req = Storable::thaw $req;

            my ($id, $type, @args) = @$req;
            my $cb = CFPlus::DB::Server->can ("do_$type")
               or die "$type: unknown database request type\n";
            my $res = pack "N/a*", Storable::freeze [$id, $cb->(@args)];
            (syswrite $fh, $res) == length $res
               or die;
         }
      };

      my $error = $@;

      eval {
         undef %DB_TABLE;
         undef $DB_ENV;

         Storable::store_fd [die => $error], $fh;
      };

      CFPlus::_exit 0;
   }

   close $fh;
   CFPlus::fh_nonblocking $FH, 1;

   $CB{die} = sub { die shift };

   $fh_r_watcher = Event->io (fd => $FH, poll => 'r', nice => 1, cb => \&fh_read);
   $fh_w_watcher = Event->io (fd => $FH, poll => 'w', nice => -1, parked => 1, cb => \&fh_write);
   $SYNC->start;
}

sub stop {
   close $FH;
}

1;

=back

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

Revision:	1.19
Committed:	Mon Aug 20 16:16:06 2007 UTC (16 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.18:	+3 -2 lines
Log Message:	do not make sycnhronous log writes, we can live with some transaction losses and doing it hurts a lot
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3	root	1.9	CFPlus::DB - async. database and filesystem access for cfplus
4	root	1.1
5			=head1 SYNOPSIS
6
7			use CFPlus::DB;
8
9			=head1 DESCRIPTION
10
11			=over 4
12
13			=cut
14
15			package CFPlus::DB;
16
17			use strict;
18			use utf8;
19
20			use Carp ();
21	root	1.5	use Storable ();
22	root	1.9	use Config;
23	root	1.14	use Event ();
24	root	1.1
25	root	1.3	use CFPlus;
26
27	root	1.9	our $DB_HOME = "$Crossfire::VARDIR/cfplus-$BerkeleyDB::db_version-$Config{archname}";
28
29	root	1.11	sub path_of_res($) {
30	root	1.12	utf8::downgrade $_[0]; # bug in unpack "H*"
31			"$DB_HOME/res-data-" . unpack "H*", $_[0]
32	root	1.9	}
33
34	root	1.1	sub sync {
35			# for debugging
36			#CFPlus::DB::Server::req (sync => sub { });
37			CFPlus::DB::Server::sync ();
38			}
39
40	root	1.9	sub exists($$$) {
41			CFPlus::DB::Server::req (exists => @_);
42			}
43
44	root	1.1	sub get($$$) {
45			CFPlus::DB::Server::req (get => @_);
46			}
47
48			sub put($$$$) {
49			CFPlus::DB::Server::req (put => @_);
50			}
51
52	root	1.9	sub unlink($$) {
53			CFPlus::DB::Server::req (unlink => @_);
54			}
55
56	root	1.16	sub read_file($$) {
57			CFPlus::DB::Server::req (read_file => @_);
58			}
59
60	root	1.9	sub write_file($$$) {
61			CFPlus::DB::Server::req (write_file => @_);
62			}
63
64	root	1.11	sub prefetch_file($$$) {
65			CFPlus::DB::Server::req (prefetch_file => @_);
66			}
67
68	root	1.15	sub logprint($$$) {
69			CFPlus::DB::Server::req (logprint => @_);
70			}
71
72	root	1.1	our $tilemap;
73
74			sub get_tile_id_sync($) {
75			my ($hash) = @_;
76
77			# fetch the full face table first
78			unless ($tilemap) {
79			CFPlus::DB::Server::req (table => facemap => sub { $tilemap = $_[0] });
80			sync;
81			}
82
83			$tilemap->{$hash} \|\|= do {
84			my $id;
85			CFPlus::DB::Server::req (get_tile_id => $hash, sub { $id = $_[0] });
86			sync;
87			$id
88			}
89			}
90
91			package CFPlus::DB::Server;
92
93			use strict;
94
95			use Fcntl;
96			use BerkeleyDB;
97
98			our $DB_ENV;
99			our $DB_STATE;
100			our %DB_TABLE;
101
102			sub open_db {
103			mkdir $DB_HOME, 0777;
104			my $recover = $BerkeleyDB::db_version >= 4.4
105			? eval "DB_REGISTER \| DB_RECOVER"
106			: 0;
107
108			$DB_ENV = new BerkeleyDB::Env
109			-Home => $DB_HOME,
110			-Cachesize => 8_000_000,
111			-ErrFile => "$DB_HOME/errorlog.txt",
112			# -ErrPrefix => "DATABASE",
113			-Verbose => 1,
114			-Flags => DB_CREATE \| DB_RECOVER \| DB_INIT_MPOOL \| DB_INIT_LOCK \| DB_INIT_TXN \| $recover,
115	root	1.19	-SetFlags => DB_AUTO_COMMIT \| DB_LOG_AUTOREMOVE \| DB_TXN_WRITE_NOSYNC,
116	root	1.1	or die "unable to create/open database home $DB_HOME: $BerkeleyDB::Error";
117
118			1
119			}
120
121			sub table($) {
122			$DB_TABLE{$_[0]} \|\|= do {
123			my ($table) = @_;
124
125			$table =~ s/([^a-zA-Z0-9_\-])/sprintf "=%x=", ord $1/ge;
126
127			new BerkeleyDB::Btree
128			-Env => $DB_ENV,
129			-Filename => $table,
130			# -Filename => "database",
131			# -Subname => $table,
132			-Property => DB_CHKSUM,
133	root	1.19	-Flags => DB_AUTO_COMMIT \| DB_CREATE \| DB_UPGRADE,
134	root	1.1	or die "unable to create/open database table $_[0]: $BerkeleyDB::Error"
135			}
136			}
137
138			our %CB;
139			our $FH;
140			our $ID = "aaa0";
141			our ($fh_r_watcher, $fh_w_watcher);
142			our $sync_timer;
143			our $write_buf;
144			our $read_buf;
145
146	root	1.18	our $SYNC = Event->idle (min => 120, max => 180, parked => 1, cb => sub {
147	root	1.14	CFPlus::DB::Server::req (sync => sub { });
148			$_[0]->w->stop;
149			});
150
151	root	1.1	sub fh_write {
152			my $len = syswrite $FH, $write_buf;
153
154			substr $write_buf, 0, $len, "";
155
156	root	1.14	$fh_w_watcher->stop
157	root	1.1	unless length $write_buf;
158			}
159
160			sub fh_read {
161			my $status = sysread $FH, $read_buf, 16384, length $read_buf;
162
163			die "FATAL: database process died\n"
164			if $status == 0 && defined $status;
165
166			while () {
167			return if 4 > length $read_buf;
168			my $len = unpack "N", $read_buf;
169
170			return if $len + 4 > length $read_buf;
171
172			substr $read_buf, 0, 4, "";
173			my $res = Storable::thaw substr $read_buf, 0, $len, "";
174
175			my ($id, @args) = @$res;
176			(delete $CB{$id})->(@args);
177			}
178			}
179
180			sub sync {
181			# biggest mess evarr
182			my $fds; (vec $fds, fileno $FH, 1) = 1;
183
184			while (1 < scalar keys %CB) {
185			my $r = $fds;
186			my $w = length $write_buf ? $fds : undef;
187			select $r, $w, undef, undef;
188
189			fh_write if vec $w, fileno $FH, 1;
190			fh_read if vec $r, fileno $FH, 1;
191			}
192			}
193
194			sub req {
195			my ($type, @args) = @_;
196			my $cb = pop @args;
197
198			my $id = ++$ID;
199			$write_buf .= pack "N/a*", Storable::freeze [$id, $type, @args];
200			$CB{$id} = $cb;
201
202	root	1.14	$fh_w_watcher->start;
203			$SYNC->start;
204	root	1.1	}
205
206			sub do_sync {
207			$DB_ENV->txn_checkpoint (0, 0, 0);
208			()
209			}
210
211	root	1.9	sub do_exists {
212			my ($db, $key) = @_;
213
214			utf8::downgrade $key;
215			my $data;
216			(table $db)->db_get ($key, $data) == 0
217			? length $data
218			: ()
219			}
220
221	root	1.1	sub do_get {
222			my ($db, $key) = @_;
223
224	root	1.5	utf8::downgrade $key;
225	root	1.1	my $data;
226			(table $db)->db_get ($key, $data) == 0
227			? $data
228			: ()
229			}
230
231			sub do_put {
232			my ($db, $key, $data) = @_;
233
234	root	1.5	utf8::downgrade $key;
235			utf8::downgrade $data;
236	root	1.1	(table $db)->db_put ($key => $data)
237			}
238
239			sub do_table {
240			my ($db) = @_;
241
242			$db = table $db;
243
244			my $cursor = $db->db_cursor;
245			my %kv;
246			my ($k, $v);
247			$kv{$k} = $v while $cursor->c_get ($k, $v, BerkeleyDB::DB_NEXT) == 0;
248
249			\%kv
250			}
251
252			sub do_get_tile_id {
253			my ($hash) = @_;
254
255			my $id;
256			my $table = table "facemap";
257
258			return $id
259			if $table->db_get ($hash, $id) == 0;
260
261			for (1..100) {
262			my $txn = $DB_ENV->txn_begin;
263			my $status = $table->db_get (id => $id);
264			if ($status == 0 \|\| $status == BerkeleyDB::DB_NOTFOUND) {
265			$id = ($id \|\| 64) + 1;
266			if ($table->db_put (id => $id) == 0
267			&& $table->db_put ($hash => $id) == 0) {
268			$txn->txn_commit;
269
270			return $id;
271			}
272			}
273			$txn->txn_abort;
274	root	1.19	select undef, undef, undef, 0.01 * rand;
275	root	1.1	}
276
277			die "maximum number of transaction retries reached - database problems?";
278			}
279
280	root	1.9	sub do_unlink {
281			unlink $_[0];
282			}
283
284	root	1.16	sub do_read_file {
285			my ($path) = @_;
286
287			utf8::downgrade $path;
288			open my $fh, "<:raw", $path
289			or return;
290			sysread $fh, my $buf, -s $fh;
291
292			$buf
293			}
294
295	root	1.9	sub do_write_file {
296	root	1.16	my ($path, $data) = @_;
297	root	1.9
298	root	1.16	utf8::downgrade $path;
299	root	1.9	utf8::downgrade $data;
300	root	1.16	open my $fh, ">:raw", $path
301	root	1.9	or return;
302	root	1.16	syswrite $fh, $data;
303	root	1.9	close $fh;
304
305			1
306			}
307
308	root	1.11	sub do_prefetch_file {
309	root	1.16	my ($path, $size) = @_;
310	root	1.11
311	root	1.16	utf8::downgrade $path;
312			open my $fh, "<:raw", $path
313	root	1.11	or return;
314			sysread $fh, my $buf, $size;
315
316			1
317			}
318
319	root	1.15	our %LOG_FH;
320
321			sub do_logprint {
322			my ($path, $line) = @_;
323
324			$LOG_FH{$path} \|\|= do {
325			open my $fh, ">>:utf8", $path
326			or warn "Couldn't open logfile $path: $!";
327
328			$fh->autoflush (1);
329
330			$fh
331			};
332
333			my ($sec, $min, $hour, $mday, $mon, $year) = localtime time;
334
335			my $ts = sprintf "%04d-%02d-%02d %02d:%02d:%02d",
336			$year + 1900, $mon + 1, $mday, $hour, $min, $sec;
337
338			print { $LOG_FH{$path} } "$ts $line\n"
339			}
340
341	root	1.1	sub run {
342			($FH, my $fh) = CFPlus::socketpipe;
343
344			my $oldfh = select $FH; $\| = 1; select $oldfh;
345			my $oldfh = select $fh; $\| = 1; select $oldfh;
346
347			my $pid = fork;
348
349			if (defined $pid && !$pid) {
350	root	1.15	local $SIG{QUIT};
351	root	1.1	local $SIG{__DIE__};
352	root	1.15	local $SIG{__WARN__};
353	root	1.1	eval {
354			close $FH;
355
356			unless (eval { open_db }) {
357	root	1.6	eval { File::Path::rmtree $DB_HOME };
358	root	1.1	open_db;
359			}
360
361			while () {
362			4 == read $fh, my $len, 4
363			or last;
364			$len = unpack "N", $len;
365			$len == read $fh, my $req, $len
366			or die "unexpected eof while reading request";
367
368			$req = Storable::thaw $req;
369
370			my ($id, $type, @args) = @$req;
371			my $cb = CFPlus::DB::Server->can ("do_$type")
372			or die "$type: unknown database request type\n";
373			my $res = pack "N/a*", Storable::freeze [$id, $cb->(@args)];
374			(syswrite $fh, $res) == length $res
375			or die;
376			}
377			};
378
379			my $error = $@;
380
381			eval {
382			undef %DB_TABLE;
383			undef $DB_ENV;
384
385			Storable::store_fd [die => $error], $fh;
386			};
387
388			CFPlus::_exit 0;
389			}
390
391			close $fh;
392	root	1.3	CFPlus::fh_nonblocking $FH, 1;
393	root	1.1
394	root	1.2	$CB{die} = sub { die shift };
395	root	1.1
396	root	1.14	$fh_r_watcher = Event->io (fd => $FH, poll => 'r', nice => 1, cb => \&fh_read);
397			$fh_w_watcher = Event->io (fd => $FH, poll => 'w', nice => -1, parked => 1, cb => \&fh_write);
398			$SYNC->start;
399	root	1.1	}
400
401	root	1.6	sub stop {
402			close $FH;
403			}
404
405	root	1.1	1;
406
407			=back
408
409			=head1 AUTHOR
410
411			Marc Lehmann <schmorp@schmorp.de>
412			http://home.schmorp.de/
413
414			=cut
415