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#include <network/poller.hpp>
#include <logger/logger.hpp>
#include <utils/timed_events.hpp>
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <signal.h>
#include <cstring>
#include <iostream>
#include <stdexcept>
Poller::Poller()
{
#if POLLER == POLL
this->nfds = 0;
#elif POLLER == EPOLL
this->epfd = ::epoll_create1(0);
if (this->epfd == -1)
{
log_error("epoll failed: " << strerror(errno));
throw std::runtime_error("Could not create epoll instance");
}
#endif
}
Poller::~Poller()
{
}
void Poller::add_socket_handler(SocketHandler* socket_handler)
{
// Don't do anything if the socket is already managed
const auto it = this->socket_handlers.find(socket_handler->get_socket());
if (it != this->socket_handlers.end())
return ;
this->socket_handlers.emplace(socket_handler->get_socket(), socket_handler);
// 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
#if POLLER == EPOLL
struct epoll_event event = {EPOLLIN, {socket_handler}};
const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_ADD, socket_handler->get_socket(), &event);
if (res == -1)
{
log_error("epoll_ctl failed: " << strerror(errno));
throw std::runtime_error("Could not add socket to epoll");
}
#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);
#if POLLER == POLL
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--;
}
}
#elif POLLER == EPOLL
const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_DEL, socket, nullptr);
if (res == -1)
{
log_error("epoll_ctl failed: " << strerror(errno));
throw std::runtime_error("Could not remove socket from epoll");
}
#endif
}
void Poller::watch_send_events(SocketHandler* socket_handler)
{
#if POLLER == POLL
for (size_t i = 0; i <= this->nfds; ++i)
{
if (this->fds[i].fd == socket_handler->get_socket())
{
this->fds[i].events = POLLIN|POLLOUT;
return;
}
}
throw std::runtime_error("Cannot watch a non-registered socket for send events");
#elif POLLER == EPOLL
struct epoll_event event = {EPOLLIN|EPOLLOUT, {socket_handler}};
const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_MOD, socket_handler->get_socket(), &event);
if (res == -1)
{
log_error("epoll_ctl failed: " << strerror(errno));
throw std::runtime_error("Could not modify socket flags in epoll");
}
#endif
}
void Poller::stop_watching_send_events(SocketHandler* socket_handler)
{
#if POLLER == POLL
for (size_t i = 0; i <= this->nfds; ++i)
{
if (this->fds[i].fd == socket_handler->get_socket())
{
this->fds[i].events = POLLIN;
return;
}
}
throw std::runtime_error("Cannot watch a non-registered socket for send events");
#elif POLLER == EPOLL
struct epoll_event event = {EPOLLIN, {socket_handler}};
const int res = ::epoll_ctl(this->epfd, EPOLL_CTL_MOD, socket_handler->get_socket(), &event);
if (res == -1)
{
log_error("epoll_ctl failed: " << strerror(errno));
throw std::runtime_error("Could not modify socket flags in epoll");
}
#endif
}
int Poller::poll(const std::chrono::milliseconds& timeout)
{
if (this->socket_handlers.empty() && timeout == utils::no_timeout)
return -1;
#if POLLER == POLL
// Convert our nice timeout into this ugly struct
struct timespec timeout_ts;
struct timespec* timeout_tsp;
if (timeout > 0s)
{
auto seconds = std::chrono::duration_cast<std::chrono::seconds>(timeout);
timeout_ts.tv_sec = seconds.count();
timeout_ts.tv_nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(timeout - seconds).count();
timeout_tsp = &timeout_ts;
}
else
timeout_tsp = nullptr;
// Unblock all signals, only during the ppoll call
sigset_t empty_signal_set;
sigemptyset(&empty_signal_set);
int nb_events = ::ppoll(this->fds, this->nfds, timeout_tsp,
&empty_signal_set);
if (nb_events < 0)
{
if (errno == EINTR)
return true;
log_error("poll failed: " << strerror(errno));
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>(nb_events) <= this->nfds);
for (size_t i = 0; i <= this->nfds && nb_events != 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();
nb_events--;
}
else if (this->fds[i].revents & POLLOUT)
{
auto socket_handler = this->socket_handlers.at(this->fds[i].fd);
if (socket_handler->is_connected())
socket_handler->on_send();
else
socket_handler->connect();
nb_events--;
}
}
return 1;
#elif POLLER == EPOLL
static const size_t max_events = 12;
struct epoll_event revents[max_events];
// Unblock all signals, only during the epoll_pwait call
sigset_t empty_signal_set;
sigemptyset(&empty_signal_set);
const int nb_events = ::epoll_pwait(this->epfd, revents, max_events, timeout.count(),
&empty_signal_set);
if (nb_events == -1)
{
if (errno == EINTR)
return 0;
log_error("epoll wait: " << strerror(errno));
throw std::runtime_error("Epoll_wait failed");
}
for (int i = 0; i < nb_events; ++i)
{
auto socket_handler = static_cast<SocketHandler*>(revents[i].data.ptr);
if (revents[i].events & EPOLLIN)
socket_handler->on_recv();
else if (revents[i].events & EPOLLOUT)
{
if (socket_handler->is_connected())
socket_handler->on_send();
else
socket_handler->connect();
}
}
return nb_events;
#endif
}
size_t Poller::size() const
{
return this->socket_handlers.size();
}
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