Netpoll

Overview

The netpoll module provides the mechanism to interact with network poller(currently only epoll supported).

Example

netpoll_register(sockfd);
while (true) {
  int conn = accept(sockfd, &addr, &len);
  if (conn >= 0) {
    async(handle_conn(conn));
  } else if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) {
    netpoll_wait_read(sockfd, 0);
  } else {
    break;
  }
}
csp_netpoll_unregister(sockfd);

Go to netpoll.c for the full example.

Index

bool csp_netpoll_register(int fd)


csp_netpoll_register registers fd to the netpoll so that the netpoll can monitor io events related to the fd.

  • fd: The file descriptor to register.

It returns true if success, otherwise false.

int csp_netpoll_wait_read(int fd, csp_timer_duration_t timeout)


csp_netpoll_wait_read blocks until we can read from the fd.

  • fd: The file descriptor registered.
  • timeout: The duration we wait in nanoseconds. If it’s 0 or negative, this argument will be ignored and it will block until we get related io events.

It returns,

  • csp_netpoll_avail when available.
  • csp_netpoll_timeout when timeout.

int csp_netpoll_wait_write(int fd, csp_timer_duration_t timeout)


csp_netpoll_wait_write blocks until we can write to the fd.

  • fd: The file descriptor registered.
  • timeout: The duration we wait in nanoseconds. If it’s 0 or negative, this argument will be ignored and it will block until we get related io events.

It returns,

  • csp_netpoll_avail when available.
  • csp_netpoll_timeout when timeout.

csp_netpoll_unregister(int fd)


csp_netpoll_unregister unregisters fd from the netpoll.

  • fd: The file descriptor to unregister.

It returns true if success, otherwise false.