eudev/udevsend.c
Kay Sievers d455b0085d allow RUN to send the environment to a local socket
RUN="socket:<name>" will send the environment in the kernel uevent
format to the named destination. Using the socket instead of the program
to pass the hotplug events to the HAL daemon, cuts down the running
time of udevstart from 0.8 to 0.4 seconds on my box.

  env -i ACTION=add DEVPATH=/block/hda/hda1 strace -s10000 ./udev block
  sendto(3, "add@/block/hda/hda1\0
    ACTION=add\0DEVPATH=/block/hda/hda1\0UDEV_LOG=3\0
    ID_TYPE=disk\0ID_MODEL=HTS726060M9AT00\0ID_SERIAL=MRH401M4G6UM9B\0
    ID_REVISION=MH4OA6BA\0ID_BUS=ata\0ID_PATH=pci-0000:00:1f.1-ide-0:0\0
    ID_FS_USAGE=other\0ID_FS_TYPE=swap\0ID_FS_VERSION=2\0
    ID_FS_UUID=9352cfef-7687-47bc-a2a3-34cf136f72e1\0
    ID_FS_LABEL=ThisIsSwap\0ID_FS_LABEL_SAFE=ThisIsSwap\0
    DEVNAME=/dev/hda1\0"

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
2005-08-01 05:07:19 +02:00

225 lines
5.1 KiB
C

/*
* udevsend.c
*
* 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 <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <linux/stddef.h>
#include "udev.h"
#include "udev_version.h"
#include "udevd.h"
#include "logging.h"
/* global variables */
static int sock = -1;
#ifdef USE_LOG
void log_message (int priority, const char *format, ...)
{
va_list args;
if (priority > udev_log_priority)
return;
va_start(args, format);
vsyslog(priority, format, args);
va_end(args);
}
#endif
static int start_daemon(void)
{
pid_t pid;
pid_t child_pid;
char *const argv[] = { "udevd", NULL };
char *const envp[] = { NULL };
pid = fork();
switch (pid) {
case 0:
/* helper child */
child_pid = fork();
switch (child_pid) {
case 0:
/* daemon with empty environment */
close(sock);
execve(UDEVD_BIN, argv, envp);
err("exec of daemon failed");
_exit(1);
case -1:
err("fork of daemon failed");
return -1;
default:
exit(0);
}
break;
case -1:
err("fork of helper failed");
return -1;
default:
waitpid(pid, NULL, 0);
}
return 0;
}
static void run_udev(const char *subsystem)
{
char *const argv[] = { "udev", (char *)subsystem, NULL };
pid_t pid;
pid = fork();
switch (pid) {
case 0:
/* child */
execv(UDEV_BIN, argv);
err("exec of udev child failed");
_exit(1);
break;
case -1:
err("fork of udev child failed");
break;
default:
waitpid(pid, NULL, 0);
}
}
int main(int argc, char *argv[], char *envp[])
{
static struct udevd_msg usend_msg;
int usend_msg_len;
int i;
int loop;
struct sockaddr_un saddr;
socklen_t addrlen;
int bufpos = 0;
int retval = 1;
int started_daemon = 0;
const char *subsystem = NULL;
logging_init("udevsend");
#ifdef USE_LOG
udev_init_config();
#endif
dbg("version %s", UDEV_VERSION);
sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
if (sock == -1) {
err("error getting socket");
goto fallback;
}
memset(&saddr, 0x00, sizeof(struct sockaddr_un));
saddr.sun_family = AF_LOCAL;
/* use abstract namespace for socket path */
strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1;
memset(&usend_msg, 0x00, sizeof(struct udevd_msg));
strcpy(usend_msg.magic, UDEV_MAGIC);
usend_msg.type = UDEVD_UEVENT_UDEVSEND;
/* copy all keys to send buffer */
for (i = 0; envp[i]; i++) {
const char *key;
int keylen;
key = envp[i];
keylen = strlen(key);
/* prevent loops in the scripts we execute */
if (strncmp(key, "UDEVD_EVENT=", 12) == 0) {
dbg("seems that the event source is not the kernel, just exit");
goto exit;
}
if (bufpos + keylen >= UEVENT_BUFFER_SIZE-1) {
err("environment buffer too small, probably not called by the kernel");
continue;
}
/* remember the SUBSYSTEM */
if (strncmp(key, "SUBSYSTEM=", 10) == 0)
subsystem = &key[10];
dbg("add '%s' to env[%i] buffer", key, i);
strcpy(&usend_msg.envbuf[bufpos], key);
bufpos += keylen + 1;
}
/* older kernels passed the SUBSYSTEM only as the first argument */
if (!subsystem && argc == 2) {
bufpos += sprintf(&usend_msg.envbuf[bufpos], "SUBSYSTEM=%s", argv[1]) + 1;
dbg("add 'SUBSYSTEM=%s' to env[%i] buffer from argv", argv[1], i);
}
usend_msg_len = offsetof(struct udevd_msg, envbuf) + bufpos;
dbg("usend_msg_len=%i", usend_msg_len);
/* If we can't send, try to start daemon and resend message */
loop = UDEVSEND_WAIT_MAX_SECONDS * UDEVSEND_WAIT_LOOP_PER_SECOND;
while (--loop) {
retval = sendto(sock, &usend_msg, usend_msg_len, 0, (struct sockaddr *)&saddr, addrlen);
if (retval != -1) {
retval = 0;
goto exit;
}
if (errno != ECONNREFUSED) {
err("error sending message (%s)", strerror(errno));
goto fallback;
}
if (!started_daemon) {
info("try to start udevd daemon");
retval = start_daemon();
if (retval) {
dbg("error starting daemon");
goto fallback;
}
dbg("udevd daemon started");
started_daemon = 1;
} else {
dbg("retry to connect %d", UDEVSEND_WAIT_MAX_SECONDS * UDEVSEND_WAIT_LOOP_PER_SECOND - loop);
usleep(1000 * 1000 / UDEVSEND_WAIT_LOOP_PER_SECOND);
}
}
fallback:
err("unable to connect to event daemon, try to call udev directly");
run_udev(subsystem);
exit:
if (sock != -1)
close(sock);
logging_close();
return retval;
}