[PATCH 2/2] http: favor chunked over Content-Length

[Eric Wong <e@yhbt.net>]

RFC 7230 is actually explicit about favoring the
"Transfer-Encoding: chunked" over a Content-Length header
when a client specifies both.
---
 http_parser.rl   | 13 +++++++++++--
 test/http_put.rb | 16 ++++++++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/http_parser.rl b/http_parser.rl
index 0685d27..835ba65 100644
--- a/http_parser.rl
+++ b/http_parser.rl
@@ -62,7 +62,12 @@ static char *skip_header(struct mog_http *http, char *buf, const char *pe)
 
 	content_length = "Content-Length:"i sep
 		(digit+) $ {
-			if (!length_incr(&http->_p.content_len, fc))
+			/*
+			 * RFC 7230 3.3.2, 3.3.3,:
+			 * favor Transfer-Encoding over Content-Length
+			 */
+			if (!http->_p.chunked &&
+					!length_incr(&http->_p.content_len, fc))
 				fbreak;
 		}
 		$! { errno = EINVAL; fbreak; }
@@ -116,7 +121,11 @@ static char *skip_header(struct mog_http *http, char *buf, const char *pe)
 		# "compress" as described in RFC 7230, so reject them, here.
 		"chunked"i
 		$! { errno = EINVAL; fbreak; }
-		eor @ { http->_p.chunked = 1; };
+		eor @ {
+			http->_p.chunked = 1;
+			/* RFC 7230 3.3.2, 3.3.3,: ignore length if chunked */
+			http->_p.content_len = 0;
+		};
 	trailer = "Trailer:"i sep
 		(("Content-MD5"i @ { http->_p.has_md5 = 1; })
 		 | header_name | ',')
diff --git a/test/http_put.rb b/test/http_put.rb
index 0479629..34e2cdb 100644
--- a/test/http_put.rb
+++ b/test/http_put.rb
@@ -226,6 +226,22 @@ def test_put_bad_content_length
     assert( ! File.exist?("#@tmpdir/dev666/foo") )
   end
 
+  def test_put_favors_chunked
+    order = [ "Transfer-Encoding: chunked", "Content-Length: 123" ]
+    %w[a b].each do
+      path = '/dev666/a'
+      req = "PUT #{path} HTTP/1.1\r\n" \
+            "#{order.join("\r\n")}\r\n\r\n" \
+            "a\r\nhelloworld\r\n0\r\n\r\n"
+      order.reverse!
+      @client.write(req)
+      resp = @client.readpartial(4096)
+      assert_match(%r{\AHTTP/1\.1 201 Created\r\n}, resp, "#{path} created")
+      assert(File.exist?("#@tmpdir#{path}"))
+      assert_equal('helloworld', File.read("#@tmpdir#{path}"))
+    end
+  end
+
   def test_content_md5_good
     req = "PUT /dev666/foo HTTP/1.1\r\n" \
           "Host: #@host:#@port\r\n" \