Initial Commit

database/perl/vendor/lib/DBM/Deep/ConfigData.pm

@@ -0,0 +1,181 @@
+package DBM::Deep::ConfigData;
+use strict;
+my $arrayref = eval do {local $/; <DATA>}
+  or die "Couldn't load ConfigData data: $@";
+close DATA;
+my ($config, $features, $auto_features) = @$arrayref;
+
+sub config { $config->{$_[1]} }
+
+sub set_config { $config->{$_[1]} = $_[2] }
+sub set_feature { $features->{$_[1]} = 0+!!$_[2] }  # Constrain to 1 or 0
+
+sub auto_feature_names { sort grep !exists $features->{$_}, keys %$auto_features }
+
+sub feature_names {
+  my @features = (sort keys %$features, auto_feature_names());
+  @features;
+}
+
+sub config_names  { sort keys %$config }
+
+sub write {
+  my $me = __FILE__;
+
+  # Can't use Module::Build::Dumper here because M::B is only a
+  # build-time prereq of this module
+  require Data::Dumper;
+
+  my $mode_orig = (stat $me)[2] & 07777;
+  chmod($mode_orig | 0222, $me); # Make it writeable
+  open(my $fh, '+<', $me) or die "Can't rewrite $me: $!";
+  seek($fh, 0, 0);
+  while (<$fh>) {
+    last if /^__DATA__$/;
+  }
+  die "Couldn't find __DATA__ token in $me" if eof($fh);
+
+  seek($fh, tell($fh), 0);
+  my $data = [$config, $features, $auto_features];
+  print($fh 'do{ my '
+	      . Data::Dumper->new([$data],['x'])->Purity(1)->Dump()
+	      . '$x; }' );
+  truncate($fh, tell($fh));
+  close $fh;
+
+  chmod($mode_orig, $me)
+    or warn "Couldn't restore permissions on $me: $!";
+}
+
+sub feature {
+  my ($package, $key) = @_;
+  return $features->{$key} if exists $features->{$key};
+
+  my $info = $auto_features->{$key} or return 0;
+
+  require Module::Build;  # XXX should get rid of this
+  foreach my $type (sort keys %$info) {
+    my $prereqs = $info->{$type};
+    next if $type eq 'description' || $type eq 'recommends';
+
+    foreach my $modname (sort keys %$prereqs) {
+      my $status = Module::Build->check_installed_status($modname, $prereqs->{$modname});
+      if ((!$status->{ok}) xor ($type =~ /conflicts$/)) { return 0; }
+      if ( ! eval "require $modname; 1" ) { return 0; }
+    }
+  }
+  return 1;
+}
+
+
+=head1 NAME
+
+DBM::Deep::ConfigData - Configuration for DBM::Deep
+
+=head1 SYNOPSIS
+
+  use DBM::Deep::ConfigData;
+  $value = DBM::Deep::ConfigData->config('foo');
+  $value = DBM::Deep::ConfigData->feature('bar');
+
+  @names = DBM::Deep::ConfigData->config_names;
+  @names = DBM::Deep::ConfigData->feature_names;
+
+  DBM::Deep::ConfigData->set_config(foo => $new_value);
+  DBM::Deep::ConfigData->set_feature(bar => $new_value);
+  DBM::Deep::ConfigData->write;  # Save changes
+
+
+=head1 DESCRIPTION
+
+This module holds the configuration data for the C<DBM::Deep>
+module.  It also provides a programmatic interface for getting or
+setting that configuration data.  Note that in order to actually make
+changes, you'll have to have write access to the C<DBM::Deep::ConfigData>
+module, and you should attempt to understand the repercussions of your
+actions.
+
+
+=head1 METHODS
+
+=over 4
+
+=item config($name)
+
+Given a string argument, returns the value of the configuration item
+by that name, or C<undef> if no such item exists.
+
+=item feature($name)
+
+Given a string argument, returns the value of the feature by that
+name, or C<undef> if no such feature exists.
+
+=item set_config($name, $value)
+
+Sets the configuration item with the given name to the given value.
+The value may be any Perl scalar that will serialize correctly using
+C<Data::Dumper>.  This includes references, objects (usually), and
+complex data structures.  It probably does not include transient
+things like filehandles or sockets.
+
+=item set_feature($name, $value)
+
+Sets the feature with the given name to the given boolean value.  The
+value will be converted to 0 or 1 automatically.
+
+=item config_names()
+
+Returns a list of all the names of config items currently defined in
+C<DBM::Deep::ConfigData>, or in scalar context the number of items.
+
+=item feature_names()
+
+Returns a list of all the names of features currently defined in
+C<DBM::Deep::ConfigData>, or in scalar context the number of features.
+
+=item auto_feature_names()
+
+Returns a list of all the names of features whose availability is
+dynamically determined, or in scalar context the number of such
+features.  Does not include such features that have later been set to
+a fixed value.
+
+=item write()
+
+Commits any changes from C<set_config()> and C<set_feature()> to disk.
+Requires write access to the C<DBM::Deep::ConfigData> module.
+
+=back
+
+
+=head1 AUTHOR
+
+C<DBM::Deep::ConfigData> was automatically created using C<Module::Build>.
+C<Module::Build> was written by Ken Williams, but he holds no
+authorship claim or copyright claim to the contents of C<DBM::Deep::ConfigData>.
+
+=cut
+
+
+__DATA__
+do{ my $x = [
+       {},
+       {},
+       {
+         'mysql_engine' => {
+                             'description' => 'DBI support via MySQL',
+                             'requires' => {
+                                             'DBD::mysql' => '4.001',
+                                             'DBI' => '1.5'
+                                           }
+                           },
+         'sqlite_engine' => {
+                              'description' => 'DBI support via SQLite',
+                              'requires' => {
+                                              'DBD::SQLite' => '1.25',
+                                              'DBI' => '1.5'
+                                            }
+                            }
+       }
+     ];
+$x; }