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/*
* udevsend.c
*
* Userspace devfs
*
* Copyright (C) 2004 Ling, Xiaofeng <xiaofeng.ling@intel.com>
* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
*
*
* 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 version 2 of the License.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <wait.h>
#include "udev.h"
#include "udevd.h"
#include "logging.h"
static inline char *get_action(void)
{
char *action;
action = getenv("ACTION");
return action;
}
static inline char *get_devpath(void)
{
char *devpath;
devpath = getenv("DEVPATH");
return devpath;
}
static inline char *get_seqnum(void)
{
char *seqnum;
seqnum = getenv("SEQNUM");
return seqnum;
}
static int build_hotplugmsg(struct hotplug_msg **ppmsg, char *action,
char *devpath, char *subsystem, int seqnum)
{
struct hotplug_msg *pmsg;
pmsg = malloc(sizeof(struct hotplug_msg));
pmsg->mtype = HOTPLUGMSGTYPE;
pmsg->seqnum = seqnum;
strncpy(pmsg->action, action, 8);
strncpy(pmsg->devpath, devpath, 128);
strncpy(pmsg->subsystem, subsystem, 16);
*ppmsg = pmsg;
return sizeof(struct hotplug_msg);
}
static void free_hotplugmsg(struct hotplug_msg *pmsg)
{
free(pmsg);
}
static int start_daemon(void)
{
pid_t pid;
pid_t child_pid;
pid = fork();
switch (pid) {
case 0:
/* helper child */
child_pid = fork();
switch (child_pid) {
case 0:
/* daemon */
execl(DEFAULT_UDEVD_EXEC, NULL);
dbg("exec of daemon failed");
exit(1);
case -1:
dbg("fork of daemon failed");
return -1;
default:
exit(0);
}
break;
case -1:
dbg("fork of helper failed");
return -1;
default:
wait(0);
}
return 0;
}
int main(int argc, char* argv[])
{
int msgid;
key_t key;
struct msqid_ds msg_queue;
struct msgbuf *pmsg;
char *action;
char *devpath;
char *subsystem;
char *seqnum;
int seq;
int retval = -EINVAL;
int size;
int loop;
struct timespec tspec;
subsystem = argv[1];
if (subsystem == NULL) {
dbg("no subsystem");
goto exit;
}
devpath = get_devpath();
if (devpath == NULL) {
dbg("no devpath");
goto exit;
}
action = get_action();
if (action == NULL) {
dbg("no action");
goto exit;
}
seqnum = get_seqnum();
if (seqnum == NULL) {
dbg("no seqnum");
goto exit;
}
seq = atoi(seqnum);
/* create ipc message queue or get id of our existing one */
key = ftok(DEFAULT_UDEVD_EXEC, IPC_KEY_ID);
size = build_hotplugmsg( (struct hotplug_msg**) &pmsg, action, devpath, subsystem, seq);
msgid = msgget(key, IPC_CREAT);
if (msgid == -1) {
dbg("error open ipc queue");
goto exit;
}
/* send ipc message to the daemon */
retval = msgsnd(msgid, pmsg, size, 0);
free_hotplugmsg( (struct hotplug_msg*) pmsg);
if (retval == -1) {
dbg("error sending ipc message");
goto exit;
}
/* get state of ipc queue */
tspec.tv_sec = 0;
tspec.tv_nsec = 10000000; /* 10 millisec */
loop = 20;
while (loop--) {
retval = msgctl(msgid, IPC_STAT, &msg_queue);
if (retval == -1) {
dbg("error getting info on ipc queue");
goto exit;
}
if (msg_queue.msg_qnum == 0)
goto exit;
nanosleep(&tspec, NULL);
}
info("message is still in the ipc queue, starting daemon...");
retval = start_daemon();
exit:
return retval;
}
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