linux-stable/Documentation/connector/ucon.c
Evgeniy Polyakov 897522ea1c [CONNECTOR]: Add userspace example code into Documentation/connector/
I was asked several times to include userspace example code into
Documentation, so if there is no policy against it, consider attached patch
for 2.6.18. This program works with included Documentation/connector/cn_test.c
connector module.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-26 18:42:00 -07:00

206 lines
4.1 KiB
C

/*
* ucon.c
*
* Copyright (c) 2004+ Evgeniy Polyakov <johnpol@2ka.mipt.ru>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <asm/types.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include <linux/connector.h>
#define DEBUG
#define NETLINK_CONNECTOR 11
#ifdef DEBUG
#define ulog(f, a...) fprintf(stdout, f, ##a)
#else
#define ulog(f, a...) do {} while (0)
#endif
static int need_exit;
static __u32 seq;
static int netlink_send(int s, struct cn_msg *msg)
{
struct nlmsghdr *nlh;
unsigned int size;
int err;
char buf[128];
struct cn_msg *m;
size = NLMSG_SPACE(sizeof(struct cn_msg) + msg->len);
nlh = (struct nlmsghdr *)buf;
nlh->nlmsg_seq = seq++;
nlh->nlmsg_pid = getpid();
nlh->nlmsg_type = NLMSG_DONE;
nlh->nlmsg_len = NLMSG_LENGTH(size - sizeof(*nlh));
nlh->nlmsg_flags = 0;
m = NLMSG_DATA(nlh);
#if 0
ulog("%s: [%08x.%08x] len=%u, seq=%u, ack=%u.\n",
__func__, msg->id.idx, msg->id.val, msg->len, msg->seq, msg->ack);
#endif
memcpy(m, msg, sizeof(*m) + msg->len);
err = send(s, nlh, size, 0);
if (err == -1)
ulog("Failed to send: %s [%d].\n",
strerror(errno), errno);
return err;
}
int main(int argc, char *argv[])
{
int s;
char buf[1024];
int len;
struct nlmsghdr *reply;
struct sockaddr_nl l_local;
struct cn_msg *data;
FILE *out;
time_t tm;
struct pollfd pfd;
if (argc < 2)
out = stdout;
else {
out = fopen(argv[1], "a+");
if (!out) {
ulog("Unable to open %s for writing: %s\n",
argv[1], strerror(errno));
out = stdout;
}
}
memset(buf, 0, sizeof(buf));
s = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
if (s == -1) {
perror("socket");
return -1;
}
l_local.nl_family = AF_NETLINK;
l_local.nl_groups = 0x123; /* bitmask of requested groups */
l_local.nl_pid = 0;
if (bind(s, (struct sockaddr *)&l_local, sizeof(struct sockaddr_nl)) == -1) {
perror("bind");
close(s);
return -1;
}
#if 0
{
int on = 0x57; /* Additional group number */
setsockopt(s, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &on, sizeof(on));
}
#endif
if (0) {
int i, j;
memset(buf, 0, sizeof(buf));
data = (struct cn_msg *)buf;
data->id.idx = 0x123;
data->id.val = 0x456;
data->seq = seq++;
data->ack = 0;
data->len = 0;
for (j=0; j<10; ++j) {
for (i=0; i<1000; ++i) {
len = netlink_send(s, data);
}
ulog("%d messages have been sent to %08x.%08x.\n", i, data->id.idx, data->id.val);
}
return 0;
}
pfd.fd = s;
while (!need_exit) {
pfd.events = POLLIN;
pfd.revents = 0;
switch (poll(&pfd, 1, -1)) {
case 0:
need_exit = 1;
break;
case -1:
if (errno != EINTR) {
need_exit = 1;
break;
}
continue;
}
if (need_exit)
break;
memset(buf, 0, sizeof(buf));
len = recv(s, buf, sizeof(buf), 0);
if (len == -1) {
perror("recv buf");
close(s);
return -1;
}
reply = (struct nlmsghdr *)buf;
switch (reply->nlmsg_type) {
case NLMSG_ERROR:
fprintf(out, "Error message received.\n");
fflush(out);
break;
case NLMSG_DONE:
data = (struct cn_msg *)NLMSG_DATA(reply);
time(&tm);
fprintf(out, "%.24s : [%x.%x] [%08u.%08u].\n",
ctime(&tm), data->id.idx, data->id.val, data->seq, data->ack);
fflush(out);
break;
default:
break;
}
}
close(s);
return 0;
}