From 091213e61e8fe047cef022a3867afff1feb0c28c Mon Sep 17 00:00:00 2001
From: Christos Tsantilas <christos@chtsanti.net>
Date: Tue, 24 Sep 2019 10:04:05 +0000
Subject: [PATCH] Bug 4987: restore support for the "cache_object://" URI
 scheme (#475)

Broken by commit 6c880a1.
---
 src/anyp/Uri.cc | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/anyp/Uri.cc b/src/anyp/Uri.cc
index a8e49f1b19..e42f7c6c02 100644
--- a/src/anyp/Uri.cc
+++ b/src/anyp/Uri.cc
@@ -142,8 +142,15 @@ uriParseScheme(Parser::Tokenizer &tok)
      * Scheme names consist of a sequence of characters beginning with a
      * letter and followed by any combination of letters, digits, plus
      * ("+"), period ("."), or hyphen ("-").
+     *
+     * The underscore ("_") required to match "cache_object://" squid
+     * special URI scheme.
      */
-    static const auto schemeChars = CharacterSet("scheme", "+.-") + CharacterSet::ALPHA + CharacterSet::DIGIT;
+    static const auto schemeChars =
+#if USE_HTTP_VIOLATIONS
+        CharacterSet("special", "_") +
+#endif
+        CharacterSet("scheme", "+.-") + CharacterSet::ALPHA + CharacterSet::DIGIT;
 
     SBuf str;
     if (tok.prefix(str, schemeChars, 16) && tok.skip(':') && CharacterSet::ALPHA[str.at(0)]) {
-- 
2.47.2