asio: Add client::request::write_trailer()

src/asio_client_request.cc

@@ -38,6 +38,10 @@ request::request() : impl_(make_unique<request_impl>()) {}
 
 request::~request() {}
 
+void request::write_trailer(header_map h) const {
+  impl_->write_trailer(std::move(h));
+}
+
 void request::cancel(uint32_t error_code) const { impl_->cancel(error_code); }
 
 void request::on_response(response_cb cb) const {

src/asio_client_request_impl.cc

@@ -34,6 +34,11 @@ namespace client {
 
 request_impl::request_impl() : strm_(nullptr) {}
 
+void request_impl::write_trailer(header_map h) {
+  auto sess = strm_->session();
+  sess->write_trailer(*strm_, std::move(h));
+}
+
 void request_impl::cancel(uint32_t error_code) {
   auto sess = strm_->session();
   sess->cancel(*strm_, error_code);

src/asio_client_request_impl.h

@@ -43,6 +43,8 @@ public:
   request_impl(const request_impl &) = delete;
   request_impl &operator=(const request_impl &) = delete;
 
+  void write_trailer(header_map h);
+
   void cancel(uint32_t error_code);
 
   void on_response(response_cb cb);

src/asio_client_session_impl.cc

@@ -330,6 +330,27 @@ bool session_impl::setup_session() {
   return true;
 }
 
+int session_impl::write_trailer(stream &strm, header_map h) {
+  int rv;
+  auto nva = std::vector<nghttp2_nv>();
+  nva.reserve(h.size());
+  for (auto &hd : h) {
+    nva.push_back(nghttp2::http2::make_nv(hd.first, hd.second.value,
+                                          hd.second.sensitive));
+  }
+
+  rv = nghttp2_submit_trailer(session_, strm.stream_id(), nva.data(),
+                              nva.size());
+
+  if (rv != 0) {
+    return -1;
+  }
+
+  signal_write();
+
+  return 0;
+}
+
 void session_impl::cancel(stream &strm, uint32_t error_code) {
   nghttp2_submit_rst_stream(session_, NGHTTP2_FLAG_NONE, strm.stream_id(),
                             error_code);

src/asio_client_session_impl.h

@@ -55,6 +55,8 @@ public:
   const connect_cb &on_connect() const;
   const error_cb &on_error() const;
 
+  int write_trailer(stream &strm, header_map h);
+
   void cancel(stream &strm, uint32_t error_code);
   void resume(stream &strm);
 

src/includes/nghttp2/asio_http2_client.h

@@ -89,6 +89,12 @@ public:
   // must not access request and response object.
   void on_close(close_cb cb) const;
 
+  // Write trailer part.  This must be called after setting both
+  // NGHTTP2_DATA_FLAG_EOF and NGHTTP2_DATA_FLAG_NO_END_STREAM set in
+  // *data_flag parameter in generator_cb passed to session::submit()
+  // function.
+  void write_trailer(header_map h) const;
+
   // Cancels this request and response with given error code.
   void cancel(uint32_t error_code = NGHTTP2_INTERNAL_ERROR) const;