Deliantra-Client/DC/DB.pm

=head1 NAME

DC::DB - async. database and filesystem access for deliantra

=head1 SYNOPSIS

 use DC::DB;

=head1 DESCRIPTION

=over 4

=cut

package DC::DB;

use strict;
use utf8;

use File::Path ();
use Carp ();
use Storable ();
use Config;
use BDB;

use DC;

our $ODBDIR  = "cfplus-" . BDB::VERSION_MAJOR . "." . BDB::VERSION_MINOR . "-$Config{archname}";
our $DBDIR   = "client-" . BDB::VERSION_MAJOR . "." . BDB::VERSION_MINOR . "-$Config{archname}";
our $DB_HOME = "$Deliantra::VARDIR/$DBDIR";

sub FIRST_TILE_ID () { 64 }

unless (-d $DB_HOME) {
   if (-d "$Deliantra::VARDIR/$ODBDIR") {
      rename "$Deliantra::VARDIR/$ODBDIR", $DB_HOME;
      print STDERR "INFO: moved old database from $Deliantra::VARDIR/$ODBDIR to $DB_HOME\n";
   } elsif (-d "$Deliantra::OLDDIR/$ODBDIR") {
      rename "$Deliantra::OLDDIR/$DBDIR", $DB_HOME;
      print STDERR "INFO: moved old database from $Deliantra::OLDDIR/$ODBDIR to $DB_HOME\n";
   } else {
      File::Path::mkpath [$DB_HOME]
         or die "unable to create database directory $DB_HOME: $!";
   }
}

BDB::max_poll_time 0.03;
BDB::max_parallel 1;

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

sub try_open_db {
   File::Path::mkpath [$DB_HOME];

   my $env = db_env_create;

   $env->set_errfile (\*STDERR);
   $env->set_msgfile (\*STDERR);
   $env->set_verbose (-1, 1);

   $env->set_flags (BDB::AUTO_COMMIT | BDB::REGION_INIT);
   $env->set_flags      (&BDB::LOG_AUTOREMOVE ) if BDB::VERSION v0, v4.7;
   $env->log_set_config (&BDB::LOG_AUTO_REMOVE) if BDB::VERSION v4.7;

   $env->set_timeout (3, BDB::SET_TXN_TIMEOUT);
   $env->set_timeout (3, BDB::SET_LOCK_TIMEOUT);

   $env->set_cachesize (0, 2048 * 1024, 0);

   db_env_open $env, $DB_HOME,
               BDB::CREATE | BDB::REGISTER | BDB::RECOVER | BDB::INIT_MPOOL | BDB::INIT_LOCK | BDB::INIT_TXN,
               0666;

   $! and die "cannot open database environment $DB_HOME: " . BDB::strerror;

   $DB_ENV = $env;

   1
}

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

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

      $DB_ENV#d#
         or return ::clienterror ("trying to create table $_[0] with empty db_env $DB_ENV" => 1);#d#

      my $db = db_create $DB_ENV;
      $db->set_flags (BDB::CHKSUM);

      db_open $db, undef, $table, undef, BDB::BTREE,
              BDB::AUTO_COMMIT | BDB::CREATE | BDB::READ_UNCOMMITTED, 0666;

      $! and "unable to open/create database table $_[0]: ". BDB::strerror;

      $db
   }
}

#############################################################################

our $WATCHER;
our $SYNC;
our $facemap;

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

   my $data;
   db_get table $db, undef, $key, $data, 0, sub {
      $cb->($! ? () : length $data);
   };
}

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

   my $data;
   db_get table $db, undef, $key, $data, 0, sub {
      $cb->($! ? () : $data);
   };
}

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

   db_put table $db, undef, $key, $data, 0, sub {
      $cb->($!);
      $SYNC->again unless $SYNC->is_active;
   };
}

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

   $db = table $db;

   my $cursor = $db->cursor;
   my %kv;

   for (;;) {
      db_c_get $cursor, my $k, my $v, BDB::NEXT;
      last if $!;
      $kv{$k} = $v;
   }

   $cb->(\%kv);
}

sub do_get_tile_id {
   my ($name, $cb) = @_;

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

   db_get $table, undef, $name => $id, 0;
   $! or return $cb->($id);

   unless ($TILE_SEQ) {
      $TILE_SEQ = $table->sequence;
      $TILE_SEQ->initial_value (FIRST_TILE_ID);
      $TILE_SEQ->set_cachesize (0);
      db_sequence_open $TILE_SEQ, undef, "id", BDB::CREATE;
   }

   db_sequence_get $TILE_SEQ, undef, 1, my $id;

   die "unable to allocate tile id: $!"
      if $!;
   
   db_put $table, undef, $name => $id, 0;
   $cb->($id);

}

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

   $facemap->{$name} ||= do {
      my $id;
      do_get_tile_id $name, sub {
         $id = $_[0];
      };
      BDB::flush;
      $id
   }
}

#############################################################################

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

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

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

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

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

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

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

#############################################################################

package DC::DB::Server;

use strict;

use EV ();
use Fcntl;

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, "";

   $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;
}

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) = DC::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} = "IGNORE";
      local $SIG{__DIE__};
      local $SIG{__WARN__};
      eval {
         close $FH;

         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 $cb = DC::DB::Server->can ("do_$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 "DB::write: $!";
         }
      };

      my $error = $@;

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

      warn $error
         if $error;

      DC::_exit 0;
   }

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

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

   $fh_r_watcher = EV::io $FH, EV::READ , \&fh_read;
   $fh_w_watcher = EV::io $FH, EV::WRITE, \&fh_write;
}

sub stop {
   close $FH;
}

package DC::DB;

sub nuke_db {
   File::Path::mkpath [$DB_HOME];
   eval { File::Path::rmtree $DB_HOME };
}

sub open_db {
   unless (eval { try_open_db }) {
      warn "$@";#d#
      eval { nuke_db };
      try_open_db;
   }

   # fetch the full face table first
   unless ($facemap) {
      do_table facemap => sub {
         $facemap = $_[0];
         delete $facemap->{id};
         my %maptile = reverse %$facemap;#d#
         if ((scalar keys %$facemap) != (scalar keys %maptile)) {#d#
            $facemap = { };#d#
            DC::error "FATAL: facemap is not a 1:1 mapping, please report this and delete your $DB_HOME directory!\n";#d#
         }#d#
      };
   }

   $WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb;
   $SYNC = EV::timer_ns 0, 60, sub {
      $_[0]->stop;
      db_env_txn_checkpoint $DB_ENV, 0, 0, 0, sub { };
   };
}

END {
   db_env_txn_checkpoint $DB_ENV, 0, 0, 0
      if $DB_ENV;

   undef $TILE_SEQ;
   %DB_TABLE = ();
   undef $DB_ENV;
}

1;

=back

=head1 AUTHOR

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

=cut

Revision:	1.41
Committed:	Wed Dec 24 04:09:27 2008 UTC (15 years, 5 months ago) by root
Branch:	MAIN
CVS Tags:	rel-2_02
Changes since 1.40:	+3 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3	root	1.31	DC::DB - async. database and filesystem access for deliantra
4	root	1.1
5			=head1 SYNOPSIS
6
7	root	1.29	use DC::DB;
8	root	1.1
9			=head1 DESCRIPTION
10
11			=over 4
12
13			=cut
14
15	root	1.29	package DC::DB;
16	root	1.1
17			use strict;
18			use utf8;
19
20	root	1.35	use File::Path ();
21	root	1.1	use Carp ();
22	root	1.5	use Storable ();
23	root	1.9	use Config;
24	root	1.24	use BDB;
25	root	1.1
26	root	1.29	use DC;
27	root	1.3
28	root	1.38	our $ODBDIR = "cfplus-" . BDB::VERSION_MAJOR . "." . BDB::VERSION_MINOR . "-$Config{archname}";
29			our $DBDIR = "client-" . BDB::VERSION_MAJOR . "." . BDB::VERSION_MINOR . "-$Config{archname}";
30	root	1.27	our $DB_HOME = "$Deliantra::VARDIR/$DBDIR";
31
32	root	1.40	sub FIRST_TILE_ID () { 64 }
33
34	root	1.35	unless (-d $DB_HOME) {
35			if (-d "$Deliantra::VARDIR/$ODBDIR") {
36			rename "$Deliantra::VARDIR/$ODBDIR", $DB_HOME;
37			print STDERR "INFO: moved old database from $Deliantra::VARDIR/$ODBDIR to $DB_HOME\n";
38			} elsif (-d "$Deliantra::OLDDIR/$ODBDIR") {
39			rename "$Deliantra::OLDDIR/$DBDIR", $DB_HOME;
40			print STDERR "INFO: moved old database from $Deliantra::OLDDIR/$ODBDIR to $DB_HOME\n";
41			} else {
42			File::Path::mkpath [$DB_HOME]
43			or die "unable to create database directory $DB_HOME: $!";
44			}
45	root	1.27	}
46	root	1.9
47	root	1.30	BDB::max_poll_time 0.03;
48	root	1.32	BDB::max_parallel 1;
49	root	1.30
50	root	1.24	our $DB_ENV;
51			our $DB_STATE;
52			our %DB_TABLE;
53	root	1.35	our $TILE_SEQ;
54	root	1.24
55	root	1.33	sub try_open_db {
56	root	1.35	File::Path::mkpath [$DB_HOME];
57	root	1.24
58	root	1.36	my $env = db_env_create;
59	root	1.24
60	root	1.36	$env->set_errfile (\*STDERR);
61			$env->set_msgfile (\*STDERR);
62			$env->set_verbose (-1, 1);
63	root	1.24
64	root	1.39	$env->set_flags (BDB::AUTO_COMMIT \| BDB::REGION_INIT);
65			$env->set_flags (&BDB::LOG_AUTOREMOVE ) if BDB::VERSION v0, v4.7;
66			$env->log_set_config (&BDB::LOG_AUTO_REMOVE) if BDB::VERSION v4.7;
67
68			$env->set_timeout (3, BDB::SET_TXN_TIMEOUT);
69			$env->set_timeout (3, BDB::SET_LOCK_TIMEOUT);
70
71	root	1.36	$env->set_cachesize (0, 2048 * 1024, 0);
72	root	1.24
73	root	1.36	db_env_open $env, $DB_HOME,
74	root	1.24	BDB::CREATE \| BDB::REGISTER \| BDB::RECOVER \| BDB::INIT_MPOOL \| BDB::INIT_LOCK \| BDB::INIT_TXN,
75			0666;
76
77			$! and die "cannot open database environment $DB_HOME: " . BDB::strerror;
78
79	root	1.36	$DB_ENV = $env;
80
81	root	1.24	1
82			}
83
84			sub table($) {
85			$DB_TABLE{$_[0]} \|\|= do {
86			my ($table) = @_;
87
88			$table =~ s/([^a-zA-Z0-9_\-])/sprintf "=%x=", ord $1/ge;
89
90	root	1.41	$DB_ENV#d#
91			or return ::clienterror ("trying to create table $_[0] with empty db_env $DB_ENV" => 1);#d#
92
93	root	1.24	my $db = db_create $DB_ENV;
94			$db->set_flags (BDB::CHKSUM);
95
96			db_open $db, undef, $table, undef, BDB::BTREE,
97			BDB::AUTO_COMMIT \| BDB::CREATE \| BDB::READ_UNCOMMITTED, 0666;
98
99			$! and "unable to open/create database table $_[0]: ". BDB::strerror;
100
101			$db
102			}
103	root	1.9	}
104
105	root	1.24	#############################################################################
106
107	root	1.33	our $WATCHER;
108			our $SYNC;
109	root	1.34	our $facemap;
110	root	1.24
111	root	1.9	sub exists($$$) {
112	root	1.24	my ($db, $key, $cb) = @_;
113
114			my $data;
115			db_get table $db, undef, $key, $data, 0, sub {
116			$cb->($! ? () : length $data);
117			};
118	root	1.9	}
119
120	root	1.1	sub get($$$) {
121	root	1.24	my ($db, $key, $cb) = @_;
122
123			my $data;
124			db_get table $db, undef, $key, $data, 0, sub {
125			$cb->($! ? () : $data);
126			};
127	root	1.1	}
128
129			sub put($$$$) {
130	root	1.24	my ($db, $key, $data, $cb) = @_;
131
132			db_put table $db, undef, $key, $data, 0, sub {
133			$cb->($!);
134			$SYNC->again unless $SYNC->is_active;
135			};
136	root	1.1	}
137
138	root	1.24	sub do_table {
139			my ($db, $cb) = @_;
140
141			$db = table $db;
142
143			my $cursor = $db->cursor;
144			my %kv;
145
146			for (;;) {
147			db_c_get $cursor, my $k, my $v, BDB::NEXT;
148			last if $!;
149			$kv{$k} = $v;
150			}
151
152			$cb->(\%kv);
153	root	1.9	}
154
155	root	1.24	sub do_get_tile_id {
156			my ($name, $cb) = @_;
157
158			my $table = table "facemap";
159			my $id;
160
161	root	1.35	db_get $table, undef, $name => $id, 0;
162	root	1.34	$! or return $cb->($id);
163	root	1.24
164	root	1.35	unless ($TILE_SEQ) {
165			$TILE_SEQ = $table->sequence;
166	root	1.40	$TILE_SEQ->initial_value (FIRST_TILE_ID);
167	root	1.35	$TILE_SEQ->set_cachesize (0);
168			db_sequence_open $TILE_SEQ, undef, "id", BDB::CREATE;
169			}
170	root	1.24
171	root	1.35	db_sequence_get $TILE_SEQ, undef, 1, my $id;
172	root	1.24
173	root	1.35	die "unable to allocate tile id: $!"
174			if $!;
175
176			db_put $table, undef, $name => $id, 0;
177			$cb->($id);
178	root	1.24
179	root	1.15	}
180
181	root	1.1	sub get_tile_id_sync($) {
182	root	1.20	my ($name) = @_;
183	root	1.1
184	root	1.34	$facemap->{$name} \|\|= do {
185	root	1.1	my $id;
186	root	1.24	do_get_tile_id $name, sub {
187			$id = $_[0];
188			};
189			BDB::flush;
190	root	1.1	$id
191			}
192			}
193
194	root	1.24	#############################################################################
195
196			sub path_of_res($) {
197			utf8::downgrade $_[0]; # bug in unpack "H*"
198			"$DB_HOME/res-data-" . unpack "H*", $_[0]
199			}
200
201			sub sync {
202			# for debugging
203	root	1.29	#DC::DB::Server::req (sync => sub { });
204			DC::DB::Server::sync ();
205	root	1.24	}
206	root	1.1
207	root	1.24	sub unlink($$) {
208	root	1.29	DC::DB::Server::req (unlink => @_);
209	root	1.24	}
210	root	1.1
211	root	1.24	sub read_file($$) {
212	root	1.29	DC::DB::Server::req (read_file => @_);
213	root	1.24	}
214	root	1.1
215	root	1.24	sub write_file($$$) {
216	root	1.29	DC::DB::Server::req (write_file => @_);
217	root	1.24	}
218	root	1.1
219	root	1.24	sub prefetch_file($$$) {
220	root	1.29	DC::DB::Server::req (prefetch_file => @_);
221	root	1.24	}
222	root	1.1
223	root	1.24	sub logprint($$$) {
224	root	1.29	DC::DB::Server::req (logprint => @_);
225	root	1.1	}
226
227	root	1.30	#############################################################################
228
229	root	1.29	package DC::DB::Server;
230	root	1.1
231	root	1.24	use strict;
232	root	1.1
233	root	1.24	use EV ();
234			use Fcntl;
235	root	1.1
236			our %CB;
237			our $FH;
238			our $ID = "aaa0";
239			our ($fh_r_watcher, $fh_w_watcher);
240			our $sync_timer;
241			our $write_buf;
242			our $read_buf;
243
244			sub fh_write {
245			my $len = syswrite $FH, $write_buf;
246
247			substr $write_buf, 0, $len, "";
248
249	root	1.14	$fh_w_watcher->stop
250	root	1.1	unless length $write_buf;
251			}
252
253			sub fh_read {
254			my $status = sysread $FH, $read_buf, 16384, length $read_buf;
255
256			die "FATAL: database process died\n"
257			if $status == 0 && defined $status;
258
259			while () {
260			return if 4 > length $read_buf;
261			my $len = unpack "N", $read_buf;
262
263			return if $len + 4 > length $read_buf;
264
265			substr $read_buf, 0, 4, "";
266			my $res = Storable::thaw substr $read_buf, 0, $len, "";
267
268			my ($id, @args) = @$res;
269			(delete $CB{$id})->(@args);
270			}
271			}
272
273			sub sync {
274			# biggest mess evarr
275			my $fds; (vec $fds, fileno $FH, 1) = 1;
276
277			while (1 < scalar keys %CB) {
278			my $r = $fds;
279			my $w = length $write_buf ? $fds : undef;
280			select $r, $w, undef, undef;
281
282			fh_write if vec $w, fileno $FH, 1;
283			fh_read if vec $r, fileno $FH, 1;
284			}
285			}
286
287			sub req {
288			my ($type, @args) = @_;
289			my $cb = pop @args;
290
291			my $id = ++$ID;
292			$write_buf .= pack "N/a*", Storable::freeze [$id, $type, @args];
293			$CB{$id} = $cb;
294
295	root	1.14	$fh_w_watcher->start;
296	root	1.1	}
297
298	root	1.9	sub do_unlink {
299			unlink $_[0];
300			}
301
302	root	1.16	sub do_read_file {
303			my ($path) = @_;
304
305			utf8::downgrade $path;
306			open my $fh, "<:raw", $path
307			or return;
308			sysread $fh, my $buf, -s $fh;
309
310			$buf
311			}
312
313	root	1.9	sub do_write_file {
314	root	1.16	my ($path, $data) = @_;
315	root	1.9
316	root	1.16	utf8::downgrade $path;
317	root	1.9	utf8::downgrade $data;
318	root	1.16	open my $fh, ">:raw", $path
319	root	1.9	or return;
320	root	1.16	syswrite $fh, $data;
321	root	1.9	close $fh;
322
323			1
324			}
325
326	root	1.11	sub do_prefetch_file {
327	root	1.16	my ($path, $size) = @_;
328	root	1.11
329	root	1.16	utf8::downgrade $path;
330			open my $fh, "<:raw", $path
331	root	1.11	or return;
332			sysread $fh, my $buf, $size;
333
334			1
335			}
336
337	root	1.15	our %LOG_FH;
338
339			sub do_logprint {
340			my ($path, $line) = @_;
341
342			$LOG_FH{$path} \|\|= do {
343			open my $fh, ">>:utf8", $path
344			or warn "Couldn't open logfile $path: $!";
345
346			$fh->autoflush (1);
347
348			$fh
349			};
350
351			my ($sec, $min, $hour, $mday, $mon, $year) = localtime time;
352
353			my $ts = sprintf "%04d-%02d-%02d %02d:%02d:%02d",
354			$year + 1900, $mon + 1, $mday, $hour, $min, $sec;
355
356			print { $LOG_FH{$path} } "$ts $line\n"
357			}
358
359	root	1.1	sub run {
360	root	1.29	($FH, my $fh) = DC::socketpipe;
361	root	1.1
362			my $oldfh = select $FH; $\| = 1; select $oldfh;
363			my $oldfh = select $fh; $\| = 1; select $oldfh;
364
365			my $pid = fork;
366
367			if (defined $pid && !$pid) {
368	root	1.30	local $SIG{QUIT} = "IGNORE";
369	root	1.1	local $SIG{__DIE__};
370	root	1.15	local $SIG{__WARN__};
371	root	1.1	eval {
372			close $FH;
373
374			while () {
375			4 == read $fh, my $len, 4
376			or last;
377			$len = unpack "N", $len;
378			$len == read $fh, my $req, $len
379			or die "unexpected eof while reading request";
380
381			$req = Storable::thaw $req;
382
383			my ($id, $type, @args) = @$req;
384	root	1.29	my $cb = DC::DB::Server->can ("do_$type")
385	root	1.1	or die "$type: unknown database request type\n";
386			my $res = pack "N/a*", Storable::freeze [$id, $cb->(@args)];
387			(syswrite $fh, $res) == length $res
388	root	1.21	or die "DB::write: $!";
389	root	1.1	}
390			};
391
392			my $error = $@;
393
394			eval {
395			Storable::store_fd [die => $error], $fh;
396			};
397
398	root	1.25	warn $error
399			if $error;
400	root	1.24
401	root	1.29	DC::_exit 0;
402	root	1.1	}
403
404			close $fh;
405	root	1.29	DC::fh_nonblocking $FH, 1;
406	root	1.1
407	root	1.2	$CB{die} = sub { die shift };
408	root	1.1
409	root	1.21	$fh_r_watcher = EV::io $FH, EV::READ , \&fh_read;
410			$fh_w_watcher = EV::io $FH, EV::WRITE, \&fh_write;
411	root	1.1	}
412
413	root	1.6	sub stop {
414			close $FH;
415			}
416
417	root	1.33	package DC::DB;
418
419	root	1.35	sub nuke_db {
420			File::Path::mkpath [$DB_HOME];
421			eval { File::Path::rmtree $DB_HOME };
422			}
423
424	root	1.33	sub open_db {
425			unless (eval { try_open_db }) {
426			warn "$@";#d#
427	root	1.35	eval { nuke_db };
428	root	1.33	try_open_db;
429			}
430
431			# fetch the full face table first
432	root	1.34	unless ($facemap) {
433	root	1.33	do_table facemap => sub {
434	root	1.34	$facemap = $_[0];
435			delete $facemap->{id};
436			my %maptile = reverse %$facemap;#d#
437			if ((scalar keys %$facemap) != (scalar keys %maptile)) {#d#
438			$facemap = { };#d#
439	root	1.33	DC::error "FATAL: facemap is not a 1:1 mapping, please report this and delete your $DB_HOME directory!\n";#d#
440			}#d#
441			};
442			}
443
444			$WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb;
445			$SYNC = EV::timer_ns 0, 60, sub {
446			$_[0]->stop;
447			db_env_txn_checkpoint $DB_ENV, 0, 0, 0, sub { };
448			};
449			}
450
451			END {
452	root	1.37	db_env_txn_checkpoint $DB_ENV, 0, 0, 0
453			if $DB_ENV;
454
455	root	1.35	undef $TILE_SEQ;
456	root	1.33	%DB_TABLE = ();
457			undef $DB_ENV;
458			}
459
460	root	1.1	1;
461
462			=back
463
464			=head1 AUTHOR
465
466			Marc Lehmann <schmorp@schmorp.de>
467			http://home.schmorp.de/
468
469			=cut
470