… | |
… | |
27 | db_sync $db; |
27 | db_sync $db; |
28 | |
28 | |
29 | # when you also use Coro, management is easy: |
29 | # when you also use Coro, management is easy: |
30 | use Coro::BDB; |
30 | use Coro::BDB; |
31 | |
31 | |
32 | # automatic result processing with AnyEvent: |
32 | # automatic event loop intergration with AnyEvent: |
33 | our $FH; open $FH, "<&=" . BDB::poll_fileno; |
33 | use AnyEvent::BDB; |
34 | our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => \&BDB::poll_cb); |
|
|
35 | |
34 | |
36 | # automatic result processing with EV: |
35 | # automatic result processing with EV: |
37 | my $WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb; |
36 | my $WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb; |
38 | |
37 | |
39 | # with Glib: |
38 | # with Glib: |
… | |
… | |
110 | use strict 'vars'; |
109 | use strict 'vars'; |
111 | |
110 | |
112 | use base 'Exporter'; |
111 | use base 'Exporter'; |
113 | |
112 | |
114 | BEGIN { |
113 | BEGIN { |
115 | our $VERSION = '1.43'; |
114 | our $VERSION = '1.5'; |
116 | |
115 | |
117 | our @BDB_REQ = qw( |
116 | our @BDB_REQ = qw( |
118 | db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect |
117 | db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect |
119 | db_env_memp_sync db_env_memp_trickle |
118 | db_env_memp_sync db_env_memp_trickle |
120 | db_open db_close db_compact db_sync db_upgrade |
119 | db_open db_close db_compact db_sync db_upgrade |
… | |
… | |
134 | |
133 | |
135 | require XSLoader; |
134 | require XSLoader; |
136 | XSLoader::load ("BDB", $VERSION); |
135 | XSLoader::load ("BDB", $VERSION); |
137 | } |
136 | } |
138 | |
137 | |
|
|
138 | =head2 WIN32 FILENAMES/DATABASE NAME MESS |
|
|
139 | |
|
|
140 | Perl on Win32 supports only ASCII filenames (the reason is that it abuses |
|
|
141 | an internal flag to store wether a filename is Unicode or ANSI, but that |
|
|
142 | flag is used for somethign else in the perl core, so there is no way to |
|
|
143 | detect wether a filename is ANSI or Unicode-encoded). The BDB module |
|
|
144 | tries to work around this issue by assuming that the filename is an ANSI |
|
|
145 | filename and BDB was built for unicode support. |
|
|
146 | |
139 | =head2 BERKELEYDB FUNCTIONS |
147 | =head2 BERKELEYDB FUNCTIONS |
140 | |
148 | |
141 | All of these are functions. The create functions simply return a new |
149 | All of these are functions. The create functions simply return a new |
142 | object and never block. All the remaining functions all take an optional |
150 | object and never block. All the remaining functions take an optional |
143 | callback as last argument. If it is missing, then the function will be |
151 | callback as last argument. If it is missing, then the function will be |
144 | executed synchronously. In both cases, C<$!> will reflect the return value |
152 | executed synchronously. In both cases, C<$!> will reflect the return value |
145 | of the function. |
153 | of the function. |
146 | |
154 | |
147 | BDB functions that cannot block (mostly functions that manipulate |
155 | BDB functions that cannot block (mostly functions that manipulate |
148 | settings) are method calls on the relevant objects, so the rule of thumb |
156 | settings) are method calls on the relevant objects, so the rule of thumb |
149 | is: if its a method, its not blocking, if its a function, it takes a |
157 | is: if it's a method, it's not blocking, if it's a function, it takes a |
150 | callback as last argument. |
158 | callback as last argument. |
151 | |
159 | |
152 | In the following, C<$int> signifies an integer return value, |
160 | In the following, C<$int> signifies an integer return value, |
153 | C<octetstring> is a "binary string" (i.e. a perl string with no character |
161 | C<octetstring> is a "binary string" (i.e. a perl string with no character |
154 | indices >255), C<U32> is an unsigned 32 bit integer, C<int> is some |
162 | indices >255), C<U32> is an unsigned 32 bit integer, C<int> is some |
… | |
… | |
440 | =item $msg = BDB::strerror [$errno] |
448 | =item $msg = BDB::strerror [$errno] |
441 | |
449 | |
442 | Returns the string corresponding to the given errno value. If no argument |
450 | Returns the string corresponding to the given errno value. If no argument |
443 | is given, use C<$!>. |
451 | is given, use C<$!>. |
444 | |
452 | |
|
|
453 | Note that the BDB module also patches the C<$!> variable directly, so you |
|
|
454 | should be able to get a bdb error string by simply stringifying C<$!>. |
|
|
455 | |
445 | =item $fileno = BDB::poll_fileno |
456 | =item $fileno = BDB::poll_fileno |
446 | |
457 | |
447 | Return the I<request result pipe file descriptor>. This filehandle must be |
458 | Return the I<request result pipe file descriptor>. This filehandle must be |
448 | polled for reading by some mechanism outside this module (e.g. Event or |
459 | polled for reading by some mechanism outside this module (e.g. Event or |
449 | select, see below or the SYNOPSIS). If the pipe becomes readable you have |
460 | select, see below or the SYNOPSIS). If the pipe becomes readable you have |
… | |
… | |
600 | |
611 | |
601 | =item BDB::set_sync_prepare $cb |
612 | =item BDB::set_sync_prepare $cb |
602 | |
613 | |
603 | Sets a callback that is called whenever a request is created without an |
614 | Sets a callback that is called whenever a request is created without an |
604 | explicit callback. It has to return two code references. The first is used |
615 | explicit callback. It has to return two code references. The first is used |
605 | as the request callback, and the second is called to wait until the first |
616 | as the request callback (it should save the return status), and the second |
|
|
617 | is called to wait until the first callback has been called (it must set |
|
|
618 | C<$!> to the return status). |
|
|
619 | |
|
|
620 | This mechanism can be used to include BDB into other event mechanisms, |
|
|
621 | such as L<AnyEvent::BDB> or L<Coro::BDB>. |
|
|
622 | |
606 | callback has been called. The default implementation works like this: |
623 | The default implementation works like this: |
607 | |
624 | |
608 | sub { |
625 | sub { |
609 | my $status; |
626 | my $status; |
610 | ( |
627 | ( |
611 | sub { $status = $! }, |
628 | sub { $status = $! }, |
612 | sub { BDB::poll while !defined $status; $! = $status }, |
629 | sub { BDB::poll while !defined $status; $! = $status }, |
613 | ) |
630 | ) |
614 | } |
631 | } |
|
|
632 | |
|
|
633 | It simply blocks the process till the request has finished and then sets |
|
|
634 | C<$!> to the return value. This means that if you don't use a callback, |
|
|
635 | BDB will simply fall back to synchronous operations. |
615 | |
636 | |
616 | =back |
637 | =back |
617 | |
638 | |
618 | =head3 STATISTICAL INFORMATION |
639 | =head3 STATISTICAL INFORMATION |
619 | |
640 | |
… | |
… | |
710 | TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>, |
731 | TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>, |
711 | above. |
732 | above. |
712 | |
733 | |
713 | =head1 SEE ALSO |
734 | =head1 SEE ALSO |
714 | |
735 | |
715 | L<Coro::BDB>, L<IO::AIO>. |
736 | L<AnyEvent::BDB> (event loop integration), L<Coro::BDB> (more natural |
|
|
737 | syntax), L<IO::AIO> (nice to have). |
716 | |
738 | |
717 | =head1 AUTHOR |
739 | =head1 AUTHOR |
718 | |
740 | |
719 | Marc Lehmann <schmorp@schmorp.de> |
741 | Marc Lehmann <schmorp@schmorp.de> |
720 | http://home.schmorp.de/ |
742 | http://home.schmorp.de/ |