#ifndef _EMACS_SOCKET_H
#define _EMACS_SOCKET_H 1

#include <assert.h>
#include <errno.h>
#include <signal.h>
#include <stddef.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/un.h>

#include <inttypes.h>
#include <sys/types.h>
#include <sys/socket.h>

/* Systemd's first passed file descriptor */
#define SD_LISTEN_FDS_START 3

/*
  Helper call for identifying a passed file descriptor. Returns 1 if
  the file descriptor is a socket of type (SOCK_DGRAM, SOCK_STREAM,
  ...), 0 otherwise. If type is 0 a socket type check will not be done
  and the call only verifies if the file descriptor refers to a
  socket. If listening is > 0 it is verified that the socket is in
  listening mode. (i.e. listen() has been called) If listening is == 0
  it is verified that the socket is not in listening mode. If
  listening is < 0 no listening mode check is done. Returns a negative
  errno style error code on failure.

  See https://www.freedesktop.org/software/systemd/man/devel/sd_is_socket.html
  for more information.
*/
int sd_is_socket(int fd, int type, int listening);

/*
  Tells systemd that daemon startup or daemon reload is finished.

  See https://www.freedesktop.org/software/systemd/man/devel/sd_notify.html#Notes
  for more information.
*/
int sd_notify_ready(void);

/*
  Tells systemd that the daemon is about to go down.

  See https://www.freedesktop.org/software/systemd/man/devel/sd_notify.html#Notes
  for more information.

 */
int sd_notify_stopping(void);

#endif