linux-stable/tools/thermal/lib/mainloop.c
Daniel Lezcano 3b7c5e8adf tools/thermal: Add util library
The next changes will provide a couple of tools using some common
functions provided by this library.

It provides basic wrappers for:

 - mainloop
 - logging
 - timestamp

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20220420160933.347088-3-daniel.lezcano@linaro.org
2022-05-19 12:11:51 +02:00

120 lines
1.7 KiB
C

// SPDX-License-Identifier: LGPL-2.1+
// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <signal.h>
#include <sys/epoll.h>
#include "mainloop.h"
#include "log.h"
static int epfd = -1;
static unsigned short nrhandler;
static sig_atomic_t exit_mainloop;
struct mainloop_data {
mainloop_callback_t cb;
void *data;
int fd;
};
static struct mainloop_data **mds;
#define MAX_EVENTS 10
int mainloop(unsigned int timeout)
{
int i, nfds;
struct epoll_event events[MAX_EVENTS];
struct mainloop_data *md;
if (epfd < 0)
return -1;
for (;;) {
nfds = epoll_wait(epfd, events, MAX_EVENTS, timeout);
if (exit_mainloop || !nfds)
return 0;
if (nfds < 0) {
if (errno == EINTR)
continue;
return -1;
}
for (i = 0; i < nfds; i++) {
md = events[i].data.ptr;
if (md->cb(md->fd, md->data) > 0)
return 0;
}
}
}
int mainloop_add(int fd, mainloop_callback_t cb, void *data)
{
struct epoll_event ev = {
.events = EPOLLIN,
};
struct mainloop_data *md;
if (fd >= nrhandler) {
mds = realloc(mds, sizeof(*mds) * (fd + 1));
if (!mds)
return -1;
nrhandler = fd + 1;
}
md = malloc(sizeof(*md));
if (!md)
return -1;
md->data = data;
md->cb = cb;
md->fd = fd;
mds[fd] = md;
ev.data.ptr = md;
if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev) < 0) {
free(md);
return -1;
}
return 0;
}
int mainloop_del(int fd)
{
if (fd >= nrhandler)
return -1;
if (epoll_ctl(epfd, EPOLL_CTL_DEL, fd, NULL) < 0)
return -1;
free(mds[fd]);
return 0;
}
int mainloop_init(void)
{
epfd = epoll_create(2);
if (epfd < 0)
return -1;
return 0;
}
void mainloop_exit(void)
{
exit_mainloop = 1;
}
void mainloop_fini(void)
{
close(epfd);
}