mirror of
https://github.com/alsa-project/alsa-utils
synced 2024-11-10 00:35:42 +01:00
3f652d3caa
This commit adds support of waiter for Linux specific epoll(7) system call. For portability to the other Unix-like systems such as xBSD, modification of Makefile.am may be required for conditional build, but this commit includes no changes for it. Below lines are examples to use this option: $ axfer transfer --waiter-type=epoll -M -P -d 2 -D hw:0,3 /dev/urandom -f dat -vvv $ axfer transfer --waiter-type=epoll -M -C -d 2 -D hw:1,0 /dev/null -r 48000 -vvv Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
107 lines
2.3 KiB
C
107 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
//
|
|
// waiter-epoll.c - Waiter for event notification by epoll(7).
|
|
//
|
|
// Copyright (c) 2018 Takashi Sakamoto <o-takashi@sakamocchi.jp>
|
|
//
|
|
// Licensed under the terms of the GNU General Public License, version 2.
|
|
|
|
#include "waiter.h"
|
|
#include "misc.h"
|
|
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
#include <sys/types.h>
|
|
#include <sys/epoll.h>
|
|
|
|
struct epoll_state {
|
|
int epfd;
|
|
struct epoll_event *events;
|
|
unsigned int ev_count;
|
|
};
|
|
|
|
static int epoll_prepare(struct waiter_context *waiter)
|
|
{
|
|
struct epoll_state *state = waiter->private_data;
|
|
int i;
|
|
|
|
state->ev_count = waiter->pfd_count;
|
|
state->events = calloc(state->ev_count, sizeof(*state->events));
|
|
if (state->events == NULL)
|
|
return -ENOMEM;
|
|
|
|
state->epfd = epoll_create(1);
|
|
if (state->epfd < 0)
|
|
return -errno;
|
|
|
|
for (i = 0; i < waiter->pfd_count; ++i) {
|
|
struct epoll_event ev = {
|
|
.data.fd = waiter->pfds[i].fd,
|
|
.events = waiter->pfds[i].events,
|
|
};
|
|
if (epoll_ctl(state->epfd, EPOLL_CTL_ADD, ev.data.fd, &ev) < 0)
|
|
return -errno;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int epoll_wait_event(struct waiter_context *waiter, int timeout_msec)
|
|
{
|
|
struct epoll_state *state = waiter->private_data;
|
|
unsigned int ev_count;
|
|
int i, j;
|
|
int err;
|
|
|
|
memset(state->events, 0, state->ev_count * sizeof(*state->events));
|
|
err = epoll_wait(state->epfd, state->events, state->ev_count,
|
|
timeout_msec);
|
|
if (err < 0)
|
|
return -errno;
|
|
ev_count = (unsigned int)err;
|
|
|
|
if (ev_count > 0) {
|
|
// Reconstruct data of pollfd structure.
|
|
for (i = 0; i < ev_count; ++i) {
|
|
struct epoll_event *ev = &state->events[i];
|
|
for (j = 0; j < waiter->pfd_count; ++j) {
|
|
if (waiter->pfds[i].fd == ev->data.fd) {
|
|
waiter->pfds[i].revents = ev->events;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return ev_count;
|
|
}
|
|
|
|
static void epoll_release(struct waiter_context *waiter)
|
|
{
|
|
struct epoll_state *state = waiter->private_data;
|
|
int i;
|
|
|
|
for (i = 0; i < waiter->pfd_count; ++i) {
|
|
int fd = waiter->pfds[i].fd;
|
|
epoll_ctl(state->epfd, EPOLL_CTL_DEL, fd, NULL);
|
|
}
|
|
|
|
free(state->events);
|
|
state->events = NULL;
|
|
|
|
close(state->epfd);
|
|
|
|
state->ev_count = 0;
|
|
state->epfd = 0;
|
|
}
|
|
|
|
const struct waiter_data waiter_epoll = {
|
|
.ops = {
|
|
.prepare = epoll_prepare,
|
|
.wait_event = epoll_wait_event,
|
|
.release = epoll_release,
|
|
},
|
|
.private_size = sizeof(struct epoll_state),
|
|
};
|