From eb2d8b5278540d55ee7844ed76e8615c1e2dded3 Mon Sep 17 00:00:00 2001
From: David Carlier <devnexen@gmail.com>
Date: Thu, 23 Apr 2026 23:11:51 +0100
Subject: [PATCH] Tests: gunzip multiple content-codings.

Exercises gunzip filter behavior when Content-Encoding contains a
comma-separated list of codings: gzip stripped and body decompressed
when it is the last-applied coding, response passed through unchanged
otherwise, and the Content-Encoding header left intact on the
pass-through path taken when the client accepts gzip.

Co-authored-by: Claude <noreply@anthropic.com>
---
 gunzip_multi.t | 159 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 159 insertions(+)
 create mode 100644 gunzip_multi.t

diff --git a/gunzip_multi.t b/gunzip_multi.t
new file mode 100644
index 00000000..3ef88cc6
--- /dev/null
+++ b/gunzip_multi.t
@@ -0,0 +1,159 @@
+#!/usr/bin/perl
+
+# Tests for gunzip filter module with multiple content-codings.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+use Socket qw/ CRLF /;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx qw/ :DEFAULT :gzip http_content /;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+eval { require IO::Compress::Gzip; };
+plan(skip_all => 'IO::Compress::Gzip not found') if $@;
+
+eval { require Compress::Zlib; };
+plan(skip_all => 'Compress::Zlib not found') if $@;
+
+my $t = Test::Nginx->new()->has(qw/http gunzip proxy/)->plan(10)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        location / {
+            gunzip on;
+            proxy_pass http://127.0.0.1:8081;
+        }
+    }
+}
+
+EOF
+
+my $plain = 'hello gunzip world';
+
+my $gzipped;
+IO::Compress::Gzip::gzip(\$plain => \$gzipped);
+
+my $deflated = Compress::Zlib::compress($plain);
+my $deflated_then_gzipped;
+IO::Compress::Gzip::gzip(\$deflated => \$deflated_then_gzipped);
+
+$t->run_daemon(\&http_daemon, port(8081),
+	$gzipped, $deflated_then_gzipped);
+$t->run()->waitforsocket('127.0.0.1:' . port(8081));
+
+###############################################################################
+
+# single "gzip" (regression)
+
+my $r = http_get('/single-gzip');
+unlike($r, qr/Content-Encoding/, 'single gzip - no content encoding');
+like(http_content($r), qr/^\Q$plain\E$/, 'single gzip - decompressed');
+
+# "deflate, gzip": outer gzip is peeled, inner deflate bytes remain
+
+$r = http_get('/deflate-gzip');
+like($r, qr/Content-Encoding: deflate/,
+	'deflate,gzip - remaining encoding preserved');
+is(http_content($r), $deflated,
+	'deflate,gzip - inner deflate bytes delivered verbatim');
+
+# "gzip, deflate": gzip is not the last-applied coding, passed through
+
+$r = http_get('/gzip-deflate');
+like($r, qr/Content-Encoding: gzip, ?deflate/i,
+	'gzip,deflate - encoding left intact');
+is(http_content($r), $deflated_then_gzipped,
+	'gzip,deflate - body passed through verbatim');
+
+# client accepts gzip -- header and body must stay consistent
+
+$r = http_gzip_request('/single-gzip');
+like($r, qr/Content-Encoding: gzip/,
+	'client accepts gzip - encoding preserved');
+like($r, qr/\Q$gzipped\E/, 'client accepts gzip - body still gzipped');
+
+# comma-separated list with several tokens before gzip
+
+$r = http_get('/many-tokens');
+like($r, qr/Content-Encoding: a,b,c,d,e,f/,
+	'many tokens - gzip stripped, other tokens preserved');
+like(http_content($r), qr/^\Q$plain\E$/, 'many tokens - decompressed');
+
+###############################################################################
+
+sub http_daemon {
+	my ($port, $gzipped, $deflated_then_gzipped) = @_;
+
+	my $server = IO::Socket::INET->new(
+		Proto => 'tcp',
+		LocalHost => "127.0.0.1:$port",
+		Listen => 5,
+		Reuse => 1
+	)
+		or die "Can't create listening socket: $!\n";
+
+	local $SIG{PIPE} = 'IGNORE';
+
+	my %responses = (
+		'/single-gzip'  => ['gzip',                   $gzipped],
+		'/deflate-gzip' => ['deflate, gzip',          $deflated_then_gzipped],
+		'/gzip-deflate' => ['gzip, deflate',          $deflated_then_gzipped],
+		'/many-tokens'  => ['a, b, c, d, e, f, gzip', $gzipped],
+	);
+
+	while (my $client = $server->accept()) {
+		$client->autoflush(1);
+
+		my $headers = '';
+		my $uri;
+
+		while (<$client>) {
+			$headers .= $_;
+			if ($headers =~ /^(?:GET|HEAD) (\S+)/m && !$uri) {
+				$uri = $1;
+			}
+			last if (/^\x0d?\x0a?$/);
+		}
+
+		next if $headers eq '';
+		next unless defined $uri && exists $responses{$uri};
+
+		my ($ce, $body) = @{$responses{$uri}};
+
+		print $client
+			"HTTP/1.1 200 OK" . CRLF
+			. "Connection: close" . CRLF
+			. "Content-Type: text/plain" . CRLF
+			. "Content-Encoding: $ce" . CRLF
+			. "Content-Length: " . length($body) . CRLF
+			. CRLF
+			. $body;
+	}
+}
+
+###############################################################################