Files
tromcho.net/epoll_manager.cpp
T
Vitaliy Filippov 4a2dcf7b6b Update the license to VNPL 1.1
VNPL 1.1 is slightly reworded to make it clear that proprietary software
interacting with Vitastor and providing some kind of service to end users isn't
a "Proxy Program" if it's not specially designed to be used with Vitastor.

For example, Windows OS running in a virtual machine stored in a Vitastor
cluster clearly isn't.
2021-02-25 23:55:33 +03:00

96 lines
2.6 KiB
C++

// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 or GNU GPL-2.0+ (see README.md for details)
#include <sys/epoll.h>
#include <sys/poll.h>
#include <unistd.h>
#include <stdexcept>
#include "epoll_manager.h"
#define MAX_EPOLL_EVENTS 64
epoll_manager_t::epoll_manager_t(ring_loop_t *ringloop)
{
this->ringloop = ringloop;
epoll_fd = epoll_create(1);
if (epoll_fd < 0)
{
throw std::runtime_error(std::string("epoll_create: ") + strerror(errno));
}
tfd = new timerfd_manager_t([this](int fd, bool wr, std::function<void(int, int)> handler) { set_fd_handler(fd, wr, handler); });
handle_epoll_events();
}
epoll_manager_t::~epoll_manager_t()
{
if (tfd)
{
delete tfd;
tfd = NULL;
}
close(epoll_fd);
}
void epoll_manager_t::set_fd_handler(int fd, bool wr, std::function<void(int, int)> handler)
{
if (handler != NULL)
{
bool exists = epoll_handlers.find(fd) != epoll_handlers.end();
epoll_event ev;
ev.data.fd = fd;
ev.events = (wr ? EPOLLOUT : 0) | EPOLLIN | EPOLLRDHUP | EPOLLET;
if (epoll_ctl(epoll_fd, exists ? EPOLL_CTL_MOD : EPOLL_CTL_ADD, fd, &ev) < 0)
{
throw std::runtime_error(std::string("epoll_ctl: ") + strerror(errno));
}
epoll_handlers[fd] = handler;
}
else
{
if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, fd, NULL) < 0 && errno != ENOENT)
{
throw std::runtime_error(std::string("epoll_ctl: ") + strerror(errno));
}
epoll_handlers.erase(fd);
}
}
void epoll_manager_t::handle_epoll_events()
{
io_uring_sqe *sqe = ringloop->get_sqe();
if (!sqe)
{
throw std::runtime_error("can't get SQE, will fall out of sync with EPOLLET");
}
ring_data_t *data = ((ring_data_t*)sqe->user_data);
my_uring_prep_poll_add(sqe, epoll_fd, POLLIN);
data->callback = [this](ring_data_t *data)
{
if (data->res < 0)
{
throw std::runtime_error(std::string("epoll failed: ") + strerror(-data->res));
}
handle_epoll_events();
};
ringloop->submit();
int nfds;
epoll_event events[MAX_EPOLL_EVENTS];
do
{
nfds = epoll_wait(epoll_fd, events, MAX_EPOLL_EVENTS, 0);
for (int i = 0; i < nfds; i++)
{
auto cb_it = epoll_handlers.find(events[i].data.fd);
if (cb_it != epoll_handlers.end())
{
auto & cb = cb_it->second;
cb(events[i].data.fd, events[i].events);
}
}
} while (nfds == MAX_EPOLL_EVENTS);
}