--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lib/ioloop-epoll.c	Mon Sep 06 01:07:26 2004 +0300
@@ -0,0 +1,250 @@
+/*
+ * Linux epoll() based ioloop handler.
+ *
+ * Copyright (c) 2004 Andrey Panin <pazke@donpac.ru>
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published 
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+/* @UNSAFE: whole file */
+
+#include "lib.h"
+#include "ioloop-internal.h"
+
+#ifdef IOLOOP_EPOLL
+
+#include <sys/epoll.h>
+#include <unistd.h>
+
+#define INITIAL_EPOLL_EVENTS	128
+
+enum {
+	EPOLL_LIST_INPUT,
+	EPOLL_LIST_OUTPUT,
+
+	EPOLL_IOS_PER_FD
+};
+
+struct ioloop_handler_data {
+	int epfd;
+	int events_size, events_pos;
+	struct epoll_event *events;
+
+	unsigned int idx_size;
+	struct io_list **fd_index;
+};
+
+struct io_list {
+	struct io *ios[EPOLL_IOS_PER_FD];
+};
+
+void io_loop_handler_init(struct ioloop *ioloop)
+{
+	struct ioloop_handler_data *data;
+
+	ioloop->handler_data = data =
+		p_new(ioloop->pool, struct ioloop_handler_data, 1);
+
+	data->events_pos = 0;
+	data->events_size = INITIAL_EPOLL_EVENTS;
+	data->events = p_new(ioloop->pool, struct epoll_event,
+			     data->events_size);
+
+	data->idx_size = INITIAL_EPOLL_EVENTS;
+	data->fd_index = p_new(ioloop->pool, struct io_list *, data->idx_size);
+
+	data->epfd = epoll_create(INITIAL_EPOLL_EVENTS);
+}
+
+void io_loop_handler_deinit(struct ioloop *ioloop)
+{
+	struct ioloop_handler_data *data = ioloop->handler_data;
+
+	close(data->epfd);
+	p_free(ioloop->pool, ioloop->handler_data->events);
+	p_free(ioloop->pool, ioloop->handler_data->fd_index);
+	p_free(ioloop->pool, ioloop->handler_data);
+}
+
+#define IO_EPOLL_INPUT	(EPOLLIN | EPOLLPRI | EPOLLERR | EPOLLHUP)
+#define IO_EPOLL_OUTPUT	(EPOLLOUT | EPOLLERR | EPOLLHUP)
+
+static int epoll_event_mask(struct io_list *list)
+{
+	int events = 0, i;
+	struct io *io;
+
+	for (i = 0; i < EPOLL_IOS_PER_FD; i++) {
+		io = list->ios[i];
+
+		if (io == NULL)
+			continue;
+
+		if (io->condition & IO_READ)
+			events |= IO_EPOLL_INPUT;
+		if (io->condition & IO_WRITE)
+			events |= IO_EPOLL_OUTPUT;
+	}
+
+	return events;
+}
+
+static int iolist_add(struct io_list *list, struct io *io)
+{
+	if ((io->condition & IO_READ) != 0) {
+		i_assert(list->ios[EPOLL_LIST_INPUT] == NULL);
+		list->ios[EPOLL_LIST_INPUT] = io;
+		return list->ios[EPOLL_LIST_OUTPUT] == NULL;
+	}
+	if ((io->condition & IO_WRITE) != 0) {
+		i_assert(list->ios[EPOLL_LIST_OUTPUT] == NULL);
+		list->ios[EPOLL_LIST_OUTPUT] = io;
+		return list->ios[EPOLL_LIST_INPUT] == NULL;
+	}
+
+	i_unreached();
+	return TRUE;
+}
+
+static int iolist_del(struct io_list *list, struct io *io)
+{
+	if (list->ios[EPOLL_LIST_INPUT] == io) {
+		list->ios[EPOLL_LIST_INPUT] = NULL;
+		return list->ios[EPOLL_LIST_OUTPUT] == NULL;
+	}
+	if (list->ios[EPOLL_LIST_OUTPUT] == io) {
+		list->ios[EPOLL_LIST_OUTPUT] = NULL;
+		return list->ios[EPOLL_LIST_INPUT] == NULL;
+	}
+
+	i_unreached();
+	return TRUE;
+}
+
+void io_loop_handle_add(struct ioloop *ioloop, struct io *io)
+{
+	struct ioloop_handler_data *data = ioloop->handler_data;
+	struct io_list *list;
+	struct epoll_event event;
+	int ret, first, op, fd = io->fd;
+
+	list = data->fd_index[fd];
+	if (list == NULL) {
+		if ((unsigned int) fd >= data->idx_size) {
+                	/* grow the fd -> iolist array */
+			unsigned int old_size = data->idx_size;
+
+			data->idx_size = nearest_power((unsigned int) fd+1);
+
+			i_assert(data->idx_size < (size_t)-1 / sizeof(int));
+
+			data->fd_index = p_realloc(ioloop->pool, data->fd_index,
+						   sizeof(int) * old_size,
+						   sizeof(int) * data->idx_size);
+		}
+
+		data->fd_index[fd] = list =
+			p_new(ioloop->pool, struct io_list, 1);
+	}
+
+	first = iolist_add(list, io);
+
+	event.data.ptr = list;
+	event.events = epoll_event_mask(list);
+
+	op = first ? EPOLL_CTL_ADD : EPOLL_CTL_MOD;
+
+	ret = epoll_ctl(data->epfd, op, fd, &event);
+	if (ret < 0)
+		i_panic("epoll_ctl(): %m");
+
+	if (data->events_pos >= data->events_size) {
+		data->events_size = nearest_power(data->events_size + 1);
+
+		p_free(ioloop->pool, data->events);
+		data->events = p_new(ioloop->pool, struct epoll_event,
+				     data->events_size);
+	}
+
+	data->events_pos++;
+}
+
+void io_loop_handle_remove(struct ioloop *ioloop, struct io *io)
+{
+	struct ioloop_handler_data *data = ioloop->handler_data;
+	struct io_list *list = data->fd_index[io->fd];
+	struct epoll_event event;
+	int ret, last, op;
+
+	last = iolist_del(list, io);
+
+	event.data.ptr = list;
+	event.events = epoll_event_mask(list);
+
+	op = last ? EPOLL_CTL_DEL : EPOLL_CTL_MOD;
+
+	ret = epoll_ctl(data->epfd, op, io->fd, &event);
+	if (ret < 0 && errno != EBADF)
+		i_fatal("epoll_ctl(): %m");
+
+	data->events_pos--;
+}
+
+void io_loop_handler_run(struct ioloop *ioloop)
+{
+	struct ioloop_handler_data *data = ioloop->handler_data;
+	struct epoll_event *event;
+	struct io_list *list;
+	struct io *io;
+	struct timeval tv;
+	unsigned int t_id;
+	int msecs, ret, i, call;
+
+        /* get the time left for next timeout task */
+	msecs = io_loop_get_wait_time(ioloop->timeouts, &tv, NULL);
+
+	ret = epoll_wait(data->epfd, data->events, data->events_size, msecs);
+	if (ret < 0 && errno != EINTR)
+		i_fatal("epoll_wait(): %m");
+
+	/* execute timeout handlers */
+        io_loop_handle_timeouts(ioloop);
+
+	if (ret <= 0 || !ioloop->running) {
+		/* No events */
+		return;
+	}
+
+	event = data->events;
+	while (ret-- > 0) {
+		list = event->data.ptr;
+
+		for (i = 0; i < EPOLL_IOS_PER_FD; i++) {
+			io = list->ios[i];
+			if (io == NULL)
+				continue;
+
+			call = FALSE;
+			if ((event->events & (EPOLLHUP | EPOLLERR)) != 0) {
+				call = TRUE;
+			} else if ((io->condition & IO_READ) != 0) {
+				call = event->events & EPOLLIN;
+			} else if ((io->condition & IO_WRITE) != 0) {
+				call = event->events & EPOLLOUT;
+			}
+
+			if (call) {
+				t_id = t_push();
+				io->callback(io->context);
+				if (t_pop() != t_id)
+					i_panic("Leaked a t_pop() call!");
+			}
+		}
+		event++;
+	}
+}
+
+#endif	/* IOLOOP_EPOLL */