1// SPDX-License-Identifier: LGPL-2.1+
  2// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
  3#include <stdlib.h>
  4#include <errno.h>
  5#include <unistd.h>
  6#include <signal.h>
  7#include <sys/epoll.h>
  8#include "mainloop.h"
  9#include "log.h"
 10
 11static int epfd = -1;
 12static unsigned short nrhandler;
 13static sig_atomic_t exit_mainloop;
 14
 15struct mainloop_data {
 16	mainloop_callback_t cb;
 17	void *data;
 18	int fd;
 19};
 20
 21static struct mainloop_data **mds;
 22
 23#define MAX_EVENTS 10
 24
 25int mainloop(unsigned int timeout)
 26{
 27	int i, nfds;
 28	struct epoll_event events[MAX_EVENTS];
 29	struct mainloop_data *md;
 30
 31	if (epfd < 0)
 32		return -1;
 33
 34	for (;;) {
 35
 36		nfds = epoll_wait(epfd, events, MAX_EVENTS, timeout);
 37
 38		if (exit_mainloop || !nfds)
 39			return 0;
 40
 41		if (nfds < 0) {
 42			if (errno == EINTR)
 43				continue;
 44			return -1;
 45		}
 46
 47		for (i = 0; i < nfds; i++) {
 48			md = events[i].data.ptr;
 49
 50			if (md->cb(md->fd, md->data) > 0)
 51				return 0;
 52		}
 53	}
 54}
 55
 56int mainloop_add(int fd, mainloop_callback_t cb, void *data)
 57{
 58	struct epoll_event ev = {
 59		.events = EPOLLIN,
 60	};
 61
 62	struct mainloop_data *md;
 63
 64	if (fd >= nrhandler) {
 65		mds = realloc(mds, sizeof(*mds) * (fd + 1));
 66		if (!mds)
 67			return -1;
 68		nrhandler = fd + 1;
 69	}
 70
 71	md = malloc(sizeof(*md));
 72	if (!md)
 73		return -1;
 74
 75	md->data = data;
 76	md->cb = cb;
 77	md->fd = fd;
 78
 79	mds[fd] = md;
 80	ev.data.ptr = md;
 81
 82	if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev) < 0) {
 83		free(md);
 84		return -1;
 85	}
 86
 87	return 0;
 88}
 89
 90int mainloop_del(int fd)
 91{
 92	if (fd >= nrhandler)
 93		return -1;
 94
 95	if (epoll_ctl(epfd, EPOLL_CTL_DEL, fd, NULL) < 0)
 96		return -1;
 97
 98	free(mds[fd]);
 99
100	return 0;
101}
102
103int mainloop_init(void)
104{
105	epfd = epoll_create(2);
106	if (epfd < 0)
107		return -1;
108
109	return 0;
110}
111
112void mainloop_exit(void)
113{
114	exit_mainloop = 1;
115}
116
117void mainloop_fini(void)
118{
119	close(epfd);
120}