http: favor DS->write(strref) when reasonable

This can avoid large memory copies when strings can't be
copy-on-write and saves us the trouble of creating new
refs in the code.

diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index 9a43069f1eda9eb31a2eead6a903dc04f4ca6d7a..4f1f88fe02e51ca0fa35e700282d7e34b89bd0e3 100644 (file)
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -209,7 +209,7 @@ sub response_header_write {
        if (($len || $chunked) && $env->{REQUEST_METHOD} ne 'HEAD') {
                more($self, $h);
        } else {
-               $self->write($h);
+               $self->write(\$h);
        }
        $alive;
 }
@@ -222,7 +222,7 @@ sub chunked_wcb ($) {
                more($self, sprintf("%x\r\n", bytes::length($_[0])));
                more($self, $_[0]);
 
-               # use $self->write("\n\n") if you care about real-time
+               # use $self->write(\"\n\n") if you care about real-time
                # streaming responses, public-inbox WWW does not.
                more($self, "\r\n");
        }
@@ -248,7 +248,7 @@ sub response_done_cb ($$) {
        sub {
                my $env = $self->{env};
                $self->{env} = undef;
-               $self->write("0\r\n\r\n") if $alive == 2;
+               $self->write(\"0\r\n\r\n") if $alive == 2;
                $self->write(sub{$alive ? next_request($self) : $self->close});
        }
 }
@@ -330,7 +330,7 @@ sub more ($$) {
                        return $self->write(substr($_[1], $n, $nlen));
                }
        }
-       $self->write($_[1]);
+       $self->write(\($_[1]));
 }
 
 sub input_prepare {
@@ -467,7 +467,7 @@ sub read_input_chunked { # unlikely...
 sub quit {
        my ($self, $status) = @_;
        my $h = "HTTP/1.1 $status " . status_message($status) . "\r\n\r\n";
-       $self->write($h);
+       $self->write(\$h);
        $self->close;
 }