Subject: bug#51133: [PATCH 1/1] Tolerate http response line without reason phrase

From: Alexey Abramov <[email-masked]>
Date: Mon, 11 Oct 2021 09:03:55 +0200

* module/web/http.scm (read-response-line): Use the end of the string,
in case a line doesn't have char-set:whitespace at the end.
* test-suite/tests/web-http.test ("read-response-line"): Add test.
---
 module/web/http.scm            | 6 ++++--
 test-suite/tests/web-http.test | 2 ++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/module/web/http.scm b/module/web/http.scm
index 4276e1744..7443bd6a4 100644
--- a/module/web/http.scm
+++ b/module/web/http.scm
@@ -1187,8 +1187,10 @@ values: the HTTP version, the response code, and the (possibly empty)
 \"reason phrase\"."
   (let* ((line (read-header-line port))
          (d0 (string-index line char-set:whitespace)) ; "delimiter zero"
-         (d1 (and d0 (string-index line char-set:whitespace
-                                   (skip-whitespace line d0)))))
+         (d1 (and d0 (or (string-index line char-set:whitespace
+                                       (skip-whitespace line d0))
+                         ;; tolerate responses with empty "reason phrase"
+                         (string-length line)))))
     (unless (and d0 d1)
       (bad-response "Bad Response-Line: ~s" line))
     (values (parse-http-version line 0 d0)
diff --git a/test-suite/tests/web-http.test b/test-suite/tests/web-http.test
index 63377349c..6d8cd1642 100644
--- a/test-suite/tests/web-http.test
+++ b/test-suite/tests/web-http.test
@@ -216,6 +216,8 @@
 
   ;; Empty reason phrases are valid; see <http://bugs.gnu.org/22273>.
   (pass-if-read-response-line "HTTP/1.1 302 "
+                              (1 . 1) 302 "")
+  (pass-if-read-response-line "HTTP/1.1 302"
                               (1 . 1) 302 ""))
 
 (with-test-prefix "write-response-line"
-- 
2.31.1