Initial work for continuations (and thus the async server).

(intention is to check bits in that don't break anything, so we can
always return to a stable base)


git-svn-id: https://svn.perl.org/qpsmtpd/branches/0.3x@676 958fd67b-6ff1-0310-b445-bb7760255be9

lib/Qpsmtpd.pm

@@ -344,14 +344,31 @@ sub run_hooks {
   my $hooks = $self->{hooks};
   if ($hooks->{$hook}) {
     my @r;
-    for my $code (@{$hooks->{$hook}}) {
+    my @local_hooks = @{$hooks->{$hook}};
+    $self->{_continuation} = [$hook, [@_], @local_hooks];
+    return $self->run_continuation();
+  }
+  return (0, '');
+}
+
+sub run_continuation {
+  my $self = shift;
+  die "No continuation in progress" unless $self->{_continuation};
+  $self->continue_read() if $self->isa('Danga::Client');
+  my $todo = $self->{_continuation};
+  $self->{_continuation} = undef;
+  my $hook = shift @$todo || die "No hook in the continuation";
+  my $args = shift @$todo || die "No hook args in the continuation";
+  my @r;
+  while (@$todo) {
+    my $code = shift @$todo;
     if ( $hook eq 'logging' ) { # without calling $self->log()
-        eval { (@r) = $code->{code}->($self, $self->transaction, @_); };
+      eval { (@r) = $code->{code}->($self, $self->transaction, @$args); };
       $@ and warn("FATAL LOGGING PLUGIN ERROR: ", $@) and next;
     }
     else {
       $self->varlog(LOGINFO, $hook, $code->{name});
-        eval { (@r) = $code->{code}->($self, $self->transaction, @_); };
+      eval { (@r) = $code->{code}->($self, $self->transaction, @$args); };
       $@ and $self->log(LOGCRIT, "FATAL PLUGIN ERROR: ", $@) and next;
 
       !defined $r[0]
@@ -363,21 +380,27 @@ sub run_hooks {
         my $tnotes = $self->transaction->notes( $code->{name} );
         $tnotes->{"hook_$hook"}->{'return'} = $r[0]
           if (!defined $tnotes || ref $tnotes eq "HASH");
-        } else {
+      }
+      else {
         my $cnotes = $self->connection->notes( $code->{name} );
         $cnotes->{"hook_$hook"}->{'return'} = $r[0]
           if (!defined $cnotes || ref $cnotes eq "HASH");
       }
       
-        # should we have a hook for "OK" too?
+      if ($r[0] == YIELD) {
-        if ($r[0] == DENY or $r[0] == DENYSOFT or
+        $self->pause_read() if $self->isa('Danga::Client');
+        $self->{_continuation} = [$hook, $args, @$todo];
+        return @r;
+      }
+      elsif ($r[0] == DENY or $r[0] == DENYSOFT or
           $r[0] == DENY_DISCONNECT or $r[0] == DENYSOFT_DISCONNECT)
       {
         $r[1] = "" if not defined $r[1];
         $self->log(LOGDEBUG, "Plugin ".$code->{name}.
 	    ", hook $hook returned ".return_code($r[0]).", $r[1]");
         $self->run_hooks("deny", $code->{name}, $r[0], $r[1]) unless ($hook eq "deny");
-        } else {
+      }
+      else {
         $r[1] = "" if not defined $r[1];
         $self->log(LOGDEBUG, "Plugin ".$code->{name}.
 	    ", hook $hook returned ".return_code($r[0]).", $r[1]");
@@ -390,9 +413,19 @@ sub run_hooks {
   }
   $r[0] = DECLINED if not defined $r[0];
   @r = map { split /\n/ } @r;
-    return @r;
+  return $self->hook_responder($hook, \@r, $args);
+}
+
+sub hook_responder {
+  my ($self, $hook, $msg, $args) = @_;
+  
+  my $code = shift @$msg;
+  
+  my $responder = $hook . '_respond';
+  if (my $meth = $self->can($responder)) {
+    return $meth->($self, $code, $msg, @$args);
   }
-  return (0, '');
+  return $code, @$msg;
 }
 
 sub _register_hook {

lib/Qpsmtpd/Constants.pm

@@ -25,6 +25,8 @@ my %return_codes = (
 	DENYSOFT_DISCONNECT    => 904,   # 450 + disconnect
 	DECLINED               => 909,
 	DONE                   => 910,
+	CONTINUATION           => 911,   # deprecated - use YIELD
+	YIELD                  => 911,
 );
 
 my $has_ipv6;