nghttpx: Fix request stall

Fix request stall if backend connection is reused and buffer is full.

integration-tests/nghttpx_http1_test.go

@@ -625,6 +625,35 @@ func TestH1H1HTTPSRedirectPort(t *testing.T) {
 	}
 }
 
+// TestH1H1POSTRequests tests that server can handle 2 requests with
+// request body.
+func TestH1H1POSTRequests(t *testing.T) {
+	st := newServerTester(nil, t, noopHandler)
+	defer st.Close()
+
+	res, err := st.http1(requestParam{
+		name: "TestH1H1POSTRequestsNo1",
+		body: make([]byte, 1),
+	})
+	if err != nil {
+		t.Fatalf("Error st.http1() = %v", err)
+	}
+	if got, want := res.status, 200; got != want {
+		t.Errorf("res.status: %v; want %v", got, want)
+	}
+
+	res, err = st.http1(requestParam{
+		name: "TestH1H1POSTRequestsNo2",
+		body: make([]byte, 65536),
+	})
+	if err != nil {
+		t.Fatalf("Error st.http1() = %v", err)
+	}
+	if got, want := res.status, 200; got != want {
+		t.Errorf("res.status: %v; want %v", got, want)
+	}
+}
+
 // // TestH1H2ConnectFailure tests that server handles the situation that
 // // connection attempt to HTTP/2 backend failed.
 // func TestH1H2ConnectFailure(t *testing.T) {

integration-tests/server_tester.go

@@ -662,7 +662,9 @@ func cloneHeader(h http.Header) http.Header {
 	return h2
 }
 
-func noopHandler(w http.ResponseWriter, r *http.Request) {}
+func noopHandler(w http.ResponseWriter, r *http.Request) {
+	ioutil.ReadAll(r.Body)
+}
 
 type APIResponse struct {
 	Status string                 `json:"status,omitempty"`

src/shrpx_downstream.cc

@@ -144,7 +144,8 @@ Downstream::Downstream(Upstream *upstream, MemchunkPool *mcpool,
       request_header_sent_(false),
       accesslog_written_(false),
       new_affinity_cookie_(false),
-      blocked_request_data_eof_(false) {
+      blocked_request_data_eof_(false),
+      expect_100_continue_(false) {
 
   auto &timeoutconf = get_config()->http2.timeout;
 
@@ -857,6 +858,11 @@ void Downstream::inspect_http1_request() {
       chunked_request_ = true;
     }
   }
+
+  auto expect = req_.fs.header(http2::HD_EXPECT);
+  expect_100_continue_ =
+      expect &&
+      util::strieq(expect->value, StringRef::from_lit("100-continue"));
 }
 
 void Downstream::inspect_http1_response() {
@@ -1159,4 +1165,8 @@ void Downstream::set_blocked_request_data_eof(bool f) {
 
 void Downstream::set_ws_key(const StringRef &key) { ws_key_ = key; }
 
+bool Downstream::get_expect_100_continue() const {
+  return expect_100_continue_;
+}
+
 } // namespace shrpx

src/shrpx_downstream.h

@@ -511,6 +511,8 @@ class Downstream {
 
   void set_ws_key(const StringRef &key);
 
+  bool get_expect_100_continue() const;
+
   enum {
     EVENT_ERROR = 0x1,
     EVENT_TIMEOUT = 0x2,
@@ -602,6 +604,8 @@ class Downstream {
   // true if eof is received from client before sending header fields
   // to backend.
   bool blocked_request_data_eof_;
+  // true if request contains "expect: 100-continue" header field.
+  bool expect_100_continue_;
 };
 
 } // namespace shrpx

src/shrpx_http_downstream_connection.cc

@@ -694,7 +694,8 @@ int HttpDownstreamConnection::push_request_headers() {
   // enables us to send headers and data in one writev system call.
   if (req.method == HTTP_CONNECT ||
       downstream_->get_blocked_request_buf()->rleft() ||
-      (!req.http2_expect_body && req.fs.content_length == 0)) {
+      (!req.http2_expect_body && req.fs.content_length == 0) ||
+      downstream_->get_expect_100_continue()) {
     signal_write();
   }
 
@@ -1177,6 +1178,19 @@ int HttpDownstreamConnection::write_first() {
   auto buf = downstream_->get_blocked_request_buf();
   buf->reset();
 
+  // upstream->resume_read() might be called in
+  // write_tls()/write_clear(), but before blocked_request_buf_ is
+  // reset.  So upstream read might still be blocked.  Let's do it
+  // again here.
+  auto input = downstream_->get_request_buf();
+  if (input->rleft() == 0) {
+    auto upstream = downstream_->get_upstream();
+    auto &req = downstream_->request();
+
+    upstream->resume_read(SHRPX_NO_BUFFER, downstream_,
+                          req.unconsumed_body_length);
+  }
+
   return 0;
 }
 

src/shrpx_https_upstream.cc

@@ -505,9 +505,7 @@ int htp_hdrs_completecb(llhttp_t *htp) {
     // and let them decide whether responds with 100 Continue or not.
     // For alternative mode, we have no backend, so just send 100
     // Continue here to make the client happy.
-    auto expect = req.fs.header(http2::HD_EXPECT);
-    if (expect &&
-        util::strieq(expect->value, StringRef::from_lit("100-continue"))) {
+    if (downstream->get_expect_100_continue()) {
       auto output = downstream->get_response_buf();
       constexpr auto res = StringRef::from_lit("HTTP/1.1 100 Continue\r\n\r\n");
       output->append(res);