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 AnyEvent ();
use Storable ();
use Config;

use CFPlus;

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

sub path_of($) {
   "$DB_HOME/res-data-$_[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 write_file($$$) {
   CFPlus::DB::Server::req (write_file => @_);
}

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,
                       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_CREATE | DB_UPGRADE,
            or die "unable to create/open database table $_[0]: $BerkeleyDB::Error"
   }
}

our $SYNC_INTERVAL = 60;

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

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

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

   undef $fh_w_watcher
      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 = AnyEvent->io (fh => $FH, poll => 'w', cb => \&fh_write);
}

sub sync_tick {
   req "sync", sub { };
   $sync_timer = AnyEvent->timer (after => $SYNC_INTERVAL, cb => \&sync_tick);
}

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;
   }

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

sub do_unlink {
   unlink $_[0];
}

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

   utf8::downgrade $file;
   utf8::downgrade $data;
   open my $fh, ">:raw", CFPlus::DB::path_of $file
      or return;
   print $fh $data;
   close $fh;

   1
}

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{__DIE__};
      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 = AnyEvent->io (fh => $FH, poll => 'r', cb => \&fh_read);

   sync_tick;
}

sub stop {
   close $FH;
}

1;

=back

=head1 AUTHOR

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

=cut

Revision:	1.10
Committed:	Fri Jul 13 05:31:31 2007 UTC (16 years, 11 months ago) by root
Branch:	MAIN
Changes since 1.9:	+1 -1 lines
Log Message:	* empty log message *
#	Content
1	=head1 NAME
2
3	CFPlus::DB - async. database and filesystem access for cfplus
4
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	use AnyEvent ();
22	use Storable ();
23	use Config;
24
25	use CFPlus;
26
27	our $DB_HOME = "$Crossfire::VARDIR/cfplus-$BerkeleyDB::db_version-$Config{archname}";
28
29	sub path_of($) {
30	"$DB_HOME/res-data-$_[0]"
31	}
32
33	sub sync {
34	# for debugging
35	#CFPlus::DB::Server::req (sync => sub { });
36	CFPlus::DB::Server::sync ();
37	}
38
39	sub exists($$$) {
40	CFPlus::DB::Server::req (exists => @_);
41	}
42
43	sub get($$$) {
44	CFPlus::DB::Server::req (get => @_);
45	}
46
47	sub put($$$$) {
48	CFPlus::DB::Server::req (put => @_);
49	}
50
51	sub unlink($$) {
52	CFPlus::DB::Server::req (unlink => @_);
53	}
54
55	sub write_file($$$) {
56	CFPlus::DB::Server::req (write_file => @_);
57	}
58
59	our $tilemap;
60
61	sub get_tile_id_sync($) {
62	my ($hash) = @_;
63
64	# fetch the full face table first
65	unless ($tilemap) {
66	CFPlus::DB::Server::req (table => facemap => sub { $tilemap = $_[0] });
67	sync;
68	}
69
70	$tilemap->{$hash} \|\|= do {
71	my $id;
72	CFPlus::DB::Server::req (get_tile_id => $hash, sub { $id = $_[0] });
73	sync;
74	$id
75	}
76	}
77
78	package CFPlus::DB::Server;
79
80	use strict;
81
82	use Fcntl;
83	use BerkeleyDB;
84
85	our $DB_ENV;
86	our $DB_STATE;
87	our %DB_TABLE;
88
89	sub open_db {
90	mkdir $DB_HOME, 0777;
91	my $recover = $BerkeleyDB::db_version >= 4.4
92	? eval "DB_REGISTER \| DB_RECOVER"
93	: 0;
94
95	$DB_ENV = new BerkeleyDB::Env
96	-Home => $DB_HOME,
97	-Cachesize => 8_000_000,
98	-ErrFile => "$DB_HOME/errorlog.txt",
99	# -ErrPrefix => "DATABASE",
100	-Verbose => 1,
101	-Flags => DB_CREATE \| DB_RECOVER \| DB_INIT_MPOOL \| DB_INIT_LOCK \| DB_INIT_TXN \| $recover,
102	-SetFlags => DB_AUTO_COMMIT \| DB_LOG_AUTOREMOVE,
103	or die "unable to create/open database home $DB_HOME: $BerkeleyDB::Error";
104
105	1
106	}
107
108	sub table($) {
109	$DB_TABLE{$_[0]} \|\|= do {
110	my ($table) = @_;
111
112	$table =~ s/([^a-zA-Z0-9_\-])/sprintf "=%x=", ord $1/ge;
113
114	new BerkeleyDB::Btree
115	-Env => $DB_ENV,
116	-Filename => $table,
117	# -Filename => "database",
118	# -Subname => $table,
119	-Property => DB_CHKSUM,
120	-Flags => DB_CREATE \| DB_UPGRADE,
121	or die "unable to create/open database table $_[0]: $BerkeleyDB::Error"
122	}
123	}
124
125	our $SYNC_INTERVAL = 60;
126
127	our %CB;
128	our $FH;
129	our $ID = "aaa0";
130	our ($fh_r_watcher, $fh_w_watcher);
131	our $sync_timer;
132	our $write_buf;
133	our $read_buf;
134
135	sub fh_write {
136	my $len = syswrite $FH, $write_buf;
137
138	substr $write_buf, 0, $len, "";
139
140	undef $fh_w_watcher
141	unless length $write_buf;
142	}
143
144	sub fh_read {
145	my $status = sysread $FH, $read_buf, 16384, length $read_buf;
146
147	die "FATAL: database process died\n"
148	if $status == 0 && defined $status;
149
150	while () {
151	return if 4 > length $read_buf;
152	my $len = unpack "N", $read_buf;
153
154	return if $len + 4 > length $read_buf;
155
156	substr $read_buf, 0, 4, "";
157	my $res = Storable::thaw substr $read_buf, 0, $len, "";
158
159	my ($id, @args) = @$res;
160	(delete $CB{$id})->(@args);
161	}
162	}
163
164	sub sync {
165	# biggest mess evarr
166	my $fds; (vec $fds, fileno $FH, 1) = 1;
167
168	while (1 < scalar keys %CB) {
169	my $r = $fds;
170	my $w = length $write_buf ? $fds : undef;
171	select $r, $w, undef, undef;
172
173	fh_write if vec $w, fileno $FH, 1;
174	fh_read if vec $r, fileno $FH, 1;
175	}
176	}
177
178	sub req {
179	my ($type, @args) = @_;
180	my $cb = pop @args;
181
182	my $id = ++$ID;
183	$write_buf .= pack "N/a*", Storable::freeze [$id, $type, @args];
184	$CB{$id} = $cb;
185
186	$fh_w_watcher = AnyEvent->io (fh => $FH, poll => 'w', cb => \&fh_write);
187	}
188
189	sub sync_tick {
190	req "sync", sub { };
191	$sync_timer = AnyEvent->timer (after => $SYNC_INTERVAL, cb => \&sync_tick);
192	}
193
194	sub do_sync {
195	$DB_ENV->txn_checkpoint (0, 0, 0);
196	()
197	}
198
199	sub do_exists {
200	my ($db, $key) = @_;
201
202	utf8::downgrade $key;
203	my $data;
204	(table $db)->db_get ($key, $data) == 0
205	? length $data
206	: ()
207	}
208
209	sub do_get {
210	my ($db, $key) = @_;
211
212	utf8::downgrade $key;
213	my $data;
214	(table $db)->db_get ($key, $data) == 0
215	? $data
216	: ()
217	}
218
219	sub do_put {
220	my ($db, $key, $data) = @_;
221
222	utf8::downgrade $key;
223	utf8::downgrade $data;
224	(table $db)->db_put ($key => $data)
225	}
226
227	sub do_table {
228	my ($db) = @_;
229
230	$db = table $db;
231
232	my $cursor = $db->db_cursor;
233	my %kv;
234	my ($k, $v);
235	$kv{$k} = $v while $cursor->c_get ($k, $v, BerkeleyDB::DB_NEXT) == 0;
236
237	\%kv
238	}
239
240	sub do_get_tile_id {
241	my ($hash) = @_;
242
243	my $id;
244	my $table = table "facemap";
245
246	return $id
247	if $table->db_get ($hash, $id) == 0;
248
249	for (1..100) {
250	my $txn = $DB_ENV->txn_begin;
251	my $status = $table->db_get (id => $id);
252	if ($status == 0 \|\| $status == BerkeleyDB::DB_NOTFOUND) {
253	$id = ($id \|\| 64) + 1;
254	if ($table->db_put (id => $id) == 0
255	&& $table->db_put ($hash => $id) == 0) {
256	$txn->txn_commit;
257
258	return $id;
259	}
260	}
261	$txn->txn_abort;
262	}
263
264	die "maximum number of transaction retries reached - database problems?";
265	}
266
267	sub do_unlink {
268	unlink $_[0];
269	}
270
271	sub do_write_file {
272	my ($file, $data) = @_;
273
274	utf8::downgrade $file;
275	utf8::downgrade $data;
276	open my $fh, ">:raw", CFPlus::DB::path_of $file
277	or return;
278	print $fh $data;
279	close $fh;
280
281	1
282	}
283
284	sub run {
285	($FH, my $fh) = CFPlus::socketpipe;
286
287	my $oldfh = select $FH; $\| = 1; select $oldfh;
288	my $oldfh = select $fh; $\| = 1; select $oldfh;
289
290	my $pid = fork;
291
292	if (defined $pid && !$pid) {
293	local $SIG{__DIE__};
294	eval {
295	close $FH;
296
297	unless (eval { open_db }) {
298	eval { File::Path::rmtree $DB_HOME };
299	open_db;
300	}
301
302	while () {
303	4 == read $fh, my $len, 4
304	or last;
305	$len = unpack "N", $len;
306	$len == read $fh, my $req, $len
307	or die "unexpected eof while reading request";
308
309	$req = Storable::thaw $req;
310
311	my ($id, $type, @args) = @$req;
312	my $cb = CFPlus::DB::Server->can ("do_$type")
313	or die "$type: unknown database request type\n";
314	my $res = pack "N/a*", Storable::freeze [$id, $cb->(@args)];
315	(syswrite $fh, $res) == length $res
316	or die;
317	}
318	};
319
320	my $error = $@;
321
322	eval {
323	undef %DB_TABLE;
324	undef $DB_ENV;
325
326	Storable::store_fd [die => $error], $fh;
327	};
328
329	CFPlus::_exit 0;
330	}
331
332	close $fh;
333	CFPlus::fh_nonblocking $FH, 1;
334
335	$CB{die} = sub { die shift };
336
337	$fh_r_watcher = AnyEvent->io (fh => $FH, poll => 'r', cb => \&fh_read);
338
339	sync_tick;
340	}
341
342	sub stop {
343	close $FH;
344	}
345
346	1;
347
348	=back
349
350	=head1 AUTHOR
351
352	Marc Lehmann <schmorp@schmorp.de>
353	http://home.schmorp.de/
354
355	=cut
356