Working with data on the stack during async_write about websocketpp HOT 5 CLOSED

Could you please to change also the the server::connection::write_response method.

from websocketpp.

The last commit should fix the problem from a correctness perspective. I am leaving this issue open for the moment because this solution involves an awful lot of copying that I want to try and avoid. I think the protocol processors should be able to return a reference to an appropriate shared buffer rather than returning a value that gets copied into a shared buffer locally.

from websocketpp.

I have done a "homework" and had realized that it's enough to use members strings as a storage for requests and responses. Also I changed the raw method to pass a string reference as input parameter, rather to return the string. It looks not very nice but saves one string copy operation on old STL implementations without the "Rvalue references" feature of C++11 and does not require creating string on the heap using std::shared_ptr inside of the raw method. Here is a patch

File: client.hpp
------------------------------------------------- cut here -------------------------------------------------
-#include "../shared_const_buffer.hpp"
------------------------------------------------- cut here -------------------------------------------------
std::string m_handshake_key;
http::parser::request m_request;

•           std::string                                 m_request_data;
   http::parser::response      m_response;
  

  ------------------------------------------------- cut here -------------------------------------------------
  // TODO: generating this raw request involves way too much copying in cases
  // without string/vector move semantics.

- shared_const_buffer buffer(m_request.raw());

- //std::string raw = m_request.raw();

- //m_endpoint.alog().at(log::alevel::DEBUG_HANDSHAKE) << raw << log::endl;

• m_request.raw(m_request_data);

• boost::asio::async_write(
  m_connection.get_socket(),

•    //boost::asio::buffer(raw),
  

•    buffer,
  

•    boost::asio::buffer(m_request_data),
   boost::bind(
       &type::handle_write_request,
       m_connection.shared_from_this(),
  

  ------------------------------------------------- cut here -------------------------------------------------
  throw http::exception("Could not parse server response.",http::status_code::BAD_REQUEST);
  }

•    m_endpoint.alog().at(log::alevel::DEBUG_HANDSHAKE) << m_response.raw() << log::endl;
  

•           std::string response;
  

•           m_response.raw(response);
  

•    m_endpoint.alog().at(log::alevel::DEBUG_HANDSHAKE) << response << log::endl;
  
   // error checking
   if (m_response.get_status_code() != http::status_code::SWITCHING_PROTOCOLS) {
  

  ------------------------------------------------- cut here -------------------------------------------------

to be continued...

from websocketpp.

File: server.hpp
------------------------------------------------- cut here -------------------------------------------------
-#include "../shared_const_buffer.hpp"
------------------------------------------------- cut here -------------------------------------------------
http::parser::request m_request;
http::parser::response m_response;

•           std::string                                 m_response_data;
   blank_rng                   m_rng;
  

  ------------------------------------------------- cut here -------------------------------------------------
  m_response.replace_header("Server","WebSocket++/0.2.0");

• std::string raw = m_response.raw();

• m_response.raw(m_response_data);

// Hack for legacy HyBi
if (m_version == 0) {

•    raw += boost::dynamic_pointer_castprocessor::hybi_legacy<connection_type >(m_connection.m_processor)->get_key3();
  

•    m_response_data += boost::dynamic_pointer_cast<processor::hybi_legacy<connection_type> >(m_connection.m_processor)->get_key3();
  

  }

• m_endpoint.alog().at(log::alevel::DEBUG_HANDSHAKE) << raw << log::endl;

• m_endpoint.alog().at(log::alevel::DEBUG_HANDSHAKE) << m_response_data << log::endl;

boost::asio::async_write(
m_connection.get_socket(),

•    boost::asio::buffer(raw),
  

•    boost::asio::buffer(m_response_data),
   boost::bind(
       &type::handle_write_response,
       m_connection.shared_from_this(),
  

  ------------------------------------------------- cut here -------------------------------------------------

from websocketpp.

Here the last part. A few mistypings are also fixed. Additionally I used to use constant methods where is possible. So I added the const word in a couple of places.

File: Parser.hpp
------------------------------------------------- cut here -------------------------------------------------

•    throw "No Implimented";
  

•    throw "Not Implemented";
  

  ------------------------------------------------- cut here -------------------------------------------------
• std::string raw_headers() {
• std::string raw_headers() const {
  std::stringstream raw;

•    header_list::iterator it;
  

•    for (it = m_headers.begin(); it != m_headers.end(); it++) {
  

•    header_list::const_iterator it;
  

•    for (it = m_headers.cbegin(); it != m_headers.cend(); it++) {
       raw << it->first << ": " << it->second << "\r\n";
   }
  

  ------------------------------------------------- cut here -------------------------------------------------
  // TODO: validation. Make sure all required fields have been set?
• std::string raw() {
• void raw(std::string &data) const {
  std::stringstream raw;

 raw << m_method << " " << m_uri << " " << version() << "\r\n";
 raw << raw_headers() << "\r\n";

•    return raw.str();
  

•    data = raw.str();
  

  }
  ------------------------------------------------- cut here -------------------------------------------------
  // TODO: validation. Make sure all required fields have been set?
• std::string raw() {
• void raw(std::string &data) const {
  std::stringstream raw;

 raw << version() << " " << m_status_code << " " << m_status_msg << "\r\n";

@@ -237,7 +237,7 @@ public:

 raw << m_body;

•    return raw.str();
  

•    data = raw.str();
  

  }
  ------------------------------------------------- cut here -------------------------------------------------

from websocketpp.