[PATCH v2 2/2] gitweb: remove invalid http-equiv="content-type"

From: Jason Yundt <jason@jasonyundt.email>
To: git@vger.kernel.org
Cc: "Jason Yundt" <jason@jasonyundt.email>,
	"Jeff King" <peff@peff.net>,
	"Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
Subject: [PATCH v2 2/2] gitweb: remove invalid http-equiv="content-type"
Date: Mon,  7 Mar 2022 20:07:11 -0500	[thread overview]
Message-ID: <20220308010711.61817-3-jason@jasonyundt.email> (raw)
In-Reply-To: <20220307033723.175553-1-jason@jasonyundt.email>

Before this change, gitweb would generate pages which included:

	<meta http-equiv="content-type" content="application/xhtml+xml; charset=utf-8"/>

A meta element with http-equiv="content-type" is said to be in the
"Encoding declaration state". According to the HTML Standard,

	The Encoding declaration state may be used in HTML documents,
	but elements with an http-equiv attribute in that state must not
	be used in XML documents.

	Source: <https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type>

Gitweb always generates XML documents, so its use of
http-equiv="content-type" was invalid. This change replaces that tag
with

	<meta charset="utf-8"/>

which is equivalent [1] and allowed in XML documents [2].

[1]: <https://developer.mozilla.org/en-US/docs/Web/HTML/Element/meta#attr-http-equiv>
[2]: <https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-charset>

Signed-off-by: Jason Yundt <jason@jasonyundt.email>
---
 gitweb/gitweb.perl                        |  2 +-
 t/t9502-gitweb-standalone-parse-output.sh | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index fbd1c20a23..59457c1004 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -4225,7 +4225,7 @@ sub git_header_html {
 <!-- git web interface version $version, (C) 2005-2006, Kay Sievers <kay.sievers\@vrfy.org>, Christian Gierke -->
 <!-- git core binaries version $git_version -->
 <head>
-<meta http-equiv="content-type" content="$content_type; charset=utf-8"/>
+<meta charset="utf-8"/>
 <meta name="generator" content="gitweb/$version git/$git_version$mod_perl_version"/>
 <meta name="robots" content="index, nofollow"/>
 <title>$title</title>
diff --git a/t/t9502-gitweb-standalone-parse-output.sh b/t/t9502-gitweb-standalone-parse-output.sh
index e7363511dd..0b06e2d6b0 100755
--- a/t/t9502-gitweb-standalone-parse-output.sh
+++ b/t/t9502-gitweb-standalone-parse-output.sh
@@ -207,4 +207,20 @@ test_expect_success 'xss checks' '
 	xss "" "$TAG+"
 '
 
+check_encoding_meta_element() {
+	gitweb_run "$@" &&
+	! grep -E "http-equiv=['\"]?content-type" gitweb.body &&
+	grep -F '<meta charset="utf-8"/>' gitweb.body
+}
+
+# One of those can be used in XHTML, the other one can't. See:
+# <https://html.spec.whatwg.org/dev/semantics.html#attr-meta-charset>
+# <https://html.spec.whatwg.org/dev/semantics.html#attr-meta-http-equiv-content-type>
+test_expect_success 'no http-equiv="content-type", yes charset="utf-8"' '
+	check_encoding_meta_element &&
+	check_encoding_meta_element "p=.git" &&
+	check_encoding_meta_element "p=.git;a=log" &&
+	check_encoding_meta_element "p=.git;a=tree"
+'
+
 test_done
-- 
2.35.1

