First step of the connection skeleton

Basic connect, socket creating, polling, recving, etc.

src/network/poller.cpp

@@ -0,0 +1,96 @@
+#include <network/poller.hpp>
+
+#include <assert.h>
+#include <cstring>
+#include <iostream>
+
+
+Poller::Poller()
+{
+  std::cout << "Poller()" << std::endl;
+#if POLLER == POLL
+  memset(this->fds, 0, sizeof(this->fds));
+  this->nfds = 0;
+#endif
+}
+
+Poller::~Poller()
+{
+  std::cout << "~Poller()" << std::endl;
+}
+
+void Poller::add_socket_handler(std::shared_ptr<SocketHandler> socket_handler)
+{
+  // Raise an error if that socket is already in the list
+  const auto it = this->socket_handlers.find(socket_handler->get_socket());
+  if (it != this->socket_handlers.end())
+    throw std::runtime_error("Trying to insert SocketHandler already managed");
+
+  this->socket_handlers.emplace(socket_handler->get_socket(), socket_handler);
+  socket_handler->set_poller(this);
+
+  // We always watch all sockets for receive events
+#if POLLER == POLL
+  this->fds[this->nfds].fd = socket_handler->get_socket();
+  this->fds[this->nfds].events = POLLIN;
+  this->nfds++;
+#endif
+}
+
+void Poller::remove_socket_handler(const socket_t socket)
+{
+  const auto it = this->socket_handlers.find(socket);
+  if (it == this->socket_handlers.end())
+    throw std::runtime_error("Trying to remove a SocketHandler that is not managed");
+  this->socket_handlers.erase(it);
+  for (size_t i = 0; i < this->nfds; i++)
+    {
+      if (this->fds[i].fd == socket)
+        {
+          // Move all subsequent pollfd by one on the left, erasing the
+          // value of the one we remove
+          for (size_t j = i; j < this->nfds - 1; ++j)
+            {
+              this->fds[j].fd = this->fds[j+1].fd;
+              this->fds[j].events= this->fds[j+1].events;
+            }
+          this->nfds--;
+        }
+    }
+}
+
+void Poller::poll()
+{
+#if POLLER == POLL
+  std::cout << "Polling:" << std::endl;
+  for (size_t i = 0; i < this->nfds; ++i)
+    std::cout << "pollfd[" << i << "]: (" << this->fds[i].fd << ")" << std::endl;
+  int res = ::poll(this->fds, this->nfds, -1);
+  if (res < 0)
+    {
+      perror("poll");
+      throw std::runtime_error("Poll failed");
+    }
+  // We cannot possibly have more ready events than the number of fds we are
+  // watching
+  assert(static_cast<unsigned int>(res) <= this->nfds);
+  for (size_t i = 0; i <= this->nfds && res != 0; ++i)
+    {
+      if (this->fds[i].revents == 0)
+        continue;
+      else if (this->fds[i].revents & POLLIN)
+        {
+          auto socket_handler = this->socket_handlers.at(this->fds[i].fd);
+          socket_handler->on_recv();
+          res--;
+        }
+      else if (this->fds[i].revents & POLLOUT)
+        {
+          auto socket_handler = this->socket_handlers.at(this->fds[i].fd);
+          socket_handler->on_send();
+          res--;
+        }
+    }
+#endif
+}
+