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}
121