#include "fdevent.h"
#include "buffer.h"
#include "log.h"

#include <sys/types.h>

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <fcntl.h>

#ifdef USE_LINUX_EPOLL

# include <sys/epoll.h>

static void fdevent_linux_sysepoll_free(fdevents *ev) {
	close(ev->epoll_fd);
	free(ev->epoll_events);
}

static int fdevent_linux_sysepoll_event_del(fdevents *ev, int fde_ndx, int fd) {
	struct epoll_event ep;

	if (fde_ndx < 0) return -1;

	memset(&ep, 0, sizeof(ep));

	ep.data.fd = fd;
	ep.data.ptr = NULL;

	if (0 != epoll_ctl(ev->epoll_fd, EPOLL_CTL_DEL, fd, &ep)) {
		log_error_write(ev->srv, __FILE__, __LINE__, "SSS",
			"epoll_ctl failed: ", strerror(errno), ", dying");

		SEGFAULT();

		return 0;
	}


	return -1;
}

static int fdevent_linux_sysepoll_event_set(fdevents *ev, int fde_ndx, int fd, int events) {
	struct epoll_event ep;
	int add = 0;

	if (fde_ndx == -1) add = 1;

	memset(&ep, 0, sizeof(ep));

	ep.events = 0;

	if (events & FDEVENT_IN)  ep.events |= EPOLLIN;
	if (events & FDEVENT_OUT) ep.events |= EPOLLOUT;

	/**
	 *
	 * with EPOLLET we don't get a FDEVENT_HUP
	 * if the close is delay after everything has
	 * sent.
	 *
	 */

	ep.events |= EPOLLERR | EPOLLHUP /* | EPOLLET */;

	ep.data.ptr = NULL;
	ep.data.fd = fd;

	if (0 != epoll_ctl(ev->epoll_fd, add ? EPOLL_CTL_ADD : EPOLL_CTL_MOD, fd, &ep)) {
		log_error_write(ev->srv, __FILE__, __LINE__, "SSS",
			"epoll_ctl failed: ", strerror(errno), ", dying");

		SEGFAULT();

		return 0;
	}

	return fd;
}

static int fdevent_linux_sysepoll_poll(fdevents *ev, int timeout_ms) {
	return epoll_wait(ev->epoll_fd, ev->epoll_events, ev->maxfds, timeout_ms);
}

static int fdevent_linux_sysepoll_event_get_revent(fdevents *ev, size_t ndx) {
	int events = 0, e;

	e = ev->epoll_events[ndx].events;
	if (e & EPOLLIN) events |= FDEVENT_IN;
	if (e & EPOLLOUT) events |= FDEVENT_OUT;
	if (e & EPOLLERR) events |= FDEVENT_ERR;
	if (e & EPOLLHUP) events |= FDEVENT_HUP;
	if (e & EPOLLPRI) events |= FDEVENT_PRI;

	return events;
}

static int fdevent_linux_sysepoll_event_get_fd(fdevents *ev, size_t ndx) {
# if 0
	log_error_write(ev->srv, __FILE__, __LINE__, "SD, D",
		"fdevent_linux_sysepoll_event_get_fd: ", (int) ndx, ev->epoll_events[ndx].data.fd);
# endif

	return ev->epoll_events[ndx].data.fd;
}

static int fdevent_linux_sysepoll_event_next_fdndx(fdevents *ev, int ndx) {
	size_t i;

	UNUSED(ev);

	i = (ndx < 0) ? 0 : ndx + 1;

	return i;
}

int fdevent_linux_sysepoll_init(fdevents *ev) {
	ev->type = FDEVENT_HANDLER_LINUX_SYSEPOLL;
#define SET(x) \
	ev->x = fdevent_linux_sysepoll_##x;

	SET(free);
	SET(poll);

	SET(event_del);
	SET(event_set);

	SET(event_next_fdndx);
	SET(event_get_fd);
	SET(event_get_revent);

	if (-1 == (ev->epoll_fd = epoll_create(ev->maxfds))) {
		log_error_write(ev->srv, __FILE__, __LINE__, "SSS",
			"epoll_create failed (", strerror(errno), "), try to set server.event-handler = \"poll\" or \"select\"");

		return -1;
	}

	if (-1 == fcntl(ev->epoll_fd, F_SETFD, FD_CLOEXEC)) {
		log_error_write(ev->srv, __FILE__, __LINE__, "SSS",
			"fcntl on epoll-fd failed (", strerror(errno), "), try to set server.event-handler = \"poll\" or \"select\"");

		close(ev->epoll_fd);

		return -1;
	}

	ev->epoll_events = malloc(ev->maxfds * sizeof(*ev->epoll_events));

	return 0;
}

#else
int fdevent_linux_sysepoll_init(fdevents *ev) {
	UNUSED(ev);

	log_error_write(ev->srv, __FILE__, __LINE__, "S",
		"linux-sysepoll not supported, try to set server.event-handler = \"poll\" or \"select\"");

	return -1;
}
#endif
