platform_hardware_libhardwa.../uevent/uevent.c
2009-01-15 16:12:14 -08:00

78 lines
1.8 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <hardware_legacy/uevent.h>
#include <string.h>
#include <unistd.h>
#include <poll.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <linux/netlink.h>
static int fd = -1;
/* Returns 0 on failure, 1 on success */
int uevent_init()
{
struct sockaddr_nl addr;
int sz = 64*1024;
int s;
memset(&addr, 0, sizeof(addr));
addr.nl_family = AF_NETLINK;
addr.nl_pid = getpid();
addr.nl_groups = 0xffffffff;
s = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
if(s < 0)
return 0;
setsockopt(s, SOL_SOCKET, SO_RCVBUFFORCE, &sz, sizeof(sz));
if(bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
close(s);
return 0;
}
fd = s;
return (fd > 0);
}
int uevent_next_event(char* buffer, int buffer_length)
{
while (1) {
struct pollfd fds;
int nr;
fds.fd = fd;
fds.events = POLLIN;
fds.revents = 0;
nr = poll(&fds, 1, -1);
if(nr > 0 && fds.revents == POLLIN) {
int count = recv(fd, buffer, buffer_length, 0);
if (count > 0) {
return count;
}
}
}
// won't get here
return 0;
}