X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FGzipFilter.pm;h=d2eb4e6643e500f7a77cdf27aecb75380be8377c;hb=f26183401e3abfb64ad82537151f2718ac889074;hp=115660cb13b89597b448216d3102a603396526b5;hpb=b8b03f9c896432816019828b27708fa3b6903d83;p=public-inbox.git

diff --git a/lib/PublicInbox/GzipFilter.pm b/lib/PublicInbox/GzipFilter.pm
index 115660cb..d2eb4e66 100644
--- a/lib/PublicInbox/GzipFilter.pm
+++ b/lib/PublicInbox/GzipFilter.pm
@@ -6,8 +6,9 @@ package PublicInbox::GzipFilter;
 use strict;
 use parent qw(Exporter);
 use Compress::Raw::Zlib qw(Z_FINISH Z_OK);
-our @EXPORT_OK = qw(gzip_maybe);
+our @EXPORT_OK = qw(gzf_maybe);
 my %OPT = (-WindowBits => 15 + 16, -AppendOutput => 1);
+my @GZIP_HDRS = qw(Vary Accept-Encoding Content-Encoding gzip);
 
 sub new { bless {}, shift }
 
@@ -18,29 +19,34 @@ sub attach {
 	$self
 }
 
-sub gzip_maybe ($) {
-	my ($env) = @_;
-	return if (($env->{HTTP_ACCEPT_ENCODING}) // '') !~ /\bgzip\b/;
+# returns `0' and not `undef' on failure (see Www*Stream)
+sub gzf_maybe ($$) {
+	my ($res_hdr, $env) = @_;
+	return 0 if (($env->{HTTP_ACCEPT_ENCODING}) // '') !~ /\bgzip\b/;
+	my ($gz, $err) = Compress::Raw::Zlib::Deflate->new(%OPT);
+	return 0 if $err != Z_OK;
 
 	# in case Plack::Middleware::Deflater is loaded:
 	$env->{'plack.skip-deflater'} = 1;
+	push @$res_hdr, @GZIP_HDRS;
+	bless { gz => $gz }, __PACKAGE__;
+}
 
+sub gzip_or_die () {
 	my ($gz, $err) = Compress::Raw::Zlib::Deflate->new(%OPT);
-	$err == Z_OK ? $gz : undef;
+	$err == Z_OK or die "Deflate->new failed: $err";
+	$gz;
 }
 
 # for GetlineBody (via Qspawn) when NOT using $env->{'pi-httpd.async'}
+# Also used for ->getline callbacks
 sub translate ($$) {
-	my $self = $_[0];
+	my $self = $_[0]; # $_[1] => input
 
 	# allocate the zlib context lazily here, instead of in ->new.
 	# Deflate contexts are memory-intensive and this object may
 	# be sitting in the Qspawn limiter queue for a while.
-	my $gz = $self->{gz} //= do {
-		my ($g, $err) = Compress::Raw::Zlib::Deflate->new(%OPT);
-		$err == Z_OK or die "Deflate->new failed: $err";
-		$g;
-	};
+	my $gz = $self->{gz} //= gzip_or_die();
 	my $zbuf = delete($self->{zbuf});
 	if (defined $_[1]) { # my $buf = $_[1];
 		my $err = $gz->deflate($_[1], $zbuf);
@@ -61,10 +67,34 @@ sub write {
 	$_[0]->{fh}->write(translate($_[0], $_[1]));
 }
 
+# similar to ->translate; use this when we're sure we know we have
+# more data to buffer after this
+sub zmore {
+	my $self = $_[0]; # $_[1] => input
+	my $err = $self->{gz}->deflate($_[1], $self->{zbuf});
+	die "gzip->deflate: $err" if $err != Z_OK;
+	'';
+}
+
+# flushes and returns the final bit of gzipped data
+sub zflush ($;$) {
+	my $self = $_[0]; # $_[1] => final input (optional)
+	my $zbuf = delete $self->{zbuf};
+	my $gz = delete $self->{gz};
+	my $err;
+	if (defined $_[1]) {
+		$err = $gz->deflate($_[1], $zbuf);
+		die "gzip->deflate: $err" if $err != Z_OK;
+	}
+	$err = $gz->flush($zbuf, Z_FINISH);
+	die "gzip->flush: $err" if $err != Z_OK;
+	$zbuf;
+}
+
 sub close {
 	my ($self) = @_;
 	my $fh = delete $self->{fh};
-	$fh->write(translate($self, undef));
+	$fh->write(zflush($self));
 	$fh->close;
 }