*
*/
+#include <stddef.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/wait.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <time.h>
#include <fcntl.h>
+#include "list.h"
#include "udev.h"
#include "udevd.h"
#include "logging.h"
#define BUFFER_SIZE 1024
-#define EVENT_TIMEOUT_SECONDS 10
-#define DAEMON_TIMEOUT_SECONDS 30
-
static int expect_seqnum = 0;
-static struct hotplug_msg *head = NULL;
+static int lock_file = -1;
+static char *lock_filename = ".udevd_lock";
+LIST_HEAD(msg_list);
-static void sig_alarmhandler(int signum)
+static void sig_handler(int signum)
{
dbg("caught signal %d", signum);
switch (signum) {
case SIGALRM:
dbg("event timeout reached");
break;
-
+ case SIGINT:
+ case SIGTERM:
+ case SIGKILL:
+ if (lock_file >= 0) {
+ close(lock_file);
+ unlink(lock_filename);
+ }
+ exit(20 + signum);
+ break;
default:
dbg("unhandled signal");
}
static void dump_queue(void)
{
- struct hotplug_msg *p;
- p = head;
+ struct hotplug_msg *msg;
- dbg("next expected sequence is %d", expect_seqnum);
- while(p != NULL) {
- dbg("sequence %d in queue", p->seqnum);
- p = p->next;
- }
+ list_for_each_entry(msg, &msg_list, list)
+ dbg("sequence %d in queue", msg->seqnum);
}
-static void dump_msg(struct hotplug_msg *pmsg)
+static void dump_msg(struct hotplug_msg *msg)
{
dbg("sequence %d, '%s', '%s', '%s'",
- pmsg->seqnum, pmsg->action, pmsg->devpath, pmsg->subsystem);
+ msg->seqnum, msg->action, msg->devpath, msg->subsystem);
}
-static int dispatch_msg(struct hotplug_msg *pmsg)
+static int dispatch_msg(struct hotplug_msg *msg)
{
pid_t pid;
- char *argv[3];
- extern char **environ;
- dump_msg(pmsg);
+ dump_msg(msg);
- setenv("ACTION", pmsg->action, 1);
- setenv("DEVPATH", pmsg->devpath, 1);
- argv[0] = DEFAULT_UDEV_EXEC;
- argv[1] = pmsg->subsystem;
- argv[2] = NULL;
+ setenv("ACTION", msg->action, 1);
+ setenv("DEVPATH", msg->devpath, 1);
pid = fork();
switch (pid) {
case 0:
/* child */
- execve(argv[0], argv, environ);
+ execl(UDEV_EXEC, "udev", msg->subsystem, NULL);
dbg("exec of child failed");
exit(1);
break;
dbg("fork of child failed");
return -1;
default:
- wait(0);
+ wait(NULL);
}
return 0;
}
-static void set_timer(int seconds)
+static void set_timeout(int seconds)
{
- signal(SIGALRM, sig_alarmhandler);
alarm(seconds);
+ dbg("set timeout in %d seconds", seconds);
}
static void check_queue(void)
{
- struct hotplug_msg *p;
- p = head;
-
- dump_queue();
- while(head != NULL && head->seqnum == expect_seqnum) {
- dispatch_msg(head);
+ struct hotplug_msg *msg;
+ struct hotplug_msg *tmp_msg;
+ time_t msg_age;
+
+recheck:
+ /* dispatch events until one is missing */
+ list_for_each_entry_safe(msg, tmp_msg, &msg_list, list) {
+ if (msg->seqnum != expect_seqnum)
+ break;
+ dispatch_msg(msg);
expect_seqnum++;
- p = head;
- head = head->next;
- free(p);
+ list_del_init(&msg->list);
+ free(msg);
+ }
+
+ /* recalculate timeout */
+ if (list_empty(&msg_list) == 0) {
+ msg_age = time(NULL) - msg->queue_time;
+ if (msg_age > EVENT_TIMEOUT_SECONDS-1) {
+ info("event %d, age %li seconds, skip event %d-%d",
+ msg->seqnum, msg_age, expect_seqnum, msg->seqnum-1);
+ expect_seqnum = msg->seqnum;
+ goto recheck;
+ }
+ set_timeout(EVENT_TIMEOUT_SECONDS - msg_age);
+ return;
}
- if (head != NULL)
- set_timer(EVENT_TIMEOUT_SECONDS);
- else
- set_timer(DAEMON_TIMEOUT_SECONDS);
+
+ /* queue is empty */
+ set_timeout(UDEVD_TIMEOUT_SECONDS);
}
-static void add_queue(struct hotplug_msg *pmsg)
+static int queue_msg(struct hotplug_msg *msg)
{
- struct hotplug_msg *pnewmsg;
- struct hotplug_msg *p;
- struct hotplug_msg *p1;
-
- p = head;
- p1 = NULL;
- pnewmsg = malloc(sizeof(struct hotplug_msg));
- *pnewmsg = *pmsg;
- pnewmsg->next = NULL;
- while(p != NULL && pmsg->seqnum > p->seqnum) {
- p1 = p;
- p = p->next;
- }
- pnewmsg->next = p;
- if (p1 == NULL) {
- head = pnewmsg;
- } else {
- p1->next = pnewmsg;
+ struct hotplug_msg *new_msg;
+ struct hotplug_msg *tmp_msg;
+
+ new_msg = malloc(sizeof(*new_msg));
+ if (new_msg == NULL) {
+ dbg("error malloc");
+ return -ENOMEM;
}
- dump_queue();
-}
+ memcpy(new_msg, msg, sizeof(*new_msg));
-static int lock_file = -1;
-static char *lock_filename = ".udevd_lock";
+ /* store timestamp of queuing */
+ new_msg->queue_time = time(NULL);
+
+ /* sort message by sequence number into list*/
+ list_for_each_entry(tmp_msg, &msg_list, list)
+ if (tmp_msg->seqnum > new_msg->seqnum)
+ break;
+ list_add_tail(&new_msg->list, &tmp_msg->list);
+
+ return 0;
+}
-static int process_queue(void)
+static void work(void)
{
+ struct hotplug_msg *msg;
int msgid;
key_t key;
- struct hotplug_msg *pmsg;
char buf[BUFFER_SIZE];
int ret;
- key = ftok(DEFAULT_UDEVD_EXEC, IPC_KEY_ID);
- pmsg = (struct hotplug_msg *) buf;
+ key = ftok(UDEVD_EXEC, IPC_KEY_ID);
+ msg = (struct hotplug_msg *) buf;
msgid = msgget(key, IPC_CREAT);
if (msgid == -1) {
dbg("open message queue error");
- return -1;
+ exit(1);
}
while (1) {
ret = msgrcv(msgid, (struct msgbuf *) buf, BUFFER_SIZE-4, HOTPLUGMSGTYPE, 0);
if (ret != -1) {
- dbg("current sequence %d, expected sequence %d", pmsg->seqnum, expect_seqnum);
-
- /* init expected sequence with value from first call */
+ /* init the expected sequence with value from first call */
if (expect_seqnum == 0) {
- expect_seqnum = pmsg->seqnum;
+ expect_seqnum = msg->seqnum;
dbg("init next expected sequence number to %d", expect_seqnum);
}
-
- if (pmsg->seqnum > expect_seqnum) {
- add_queue(pmsg);
- set_timer(EVENT_TIMEOUT_SECONDS);
- } else {
- if (pmsg->seqnum == expect_seqnum) {
- dispatch_msg(pmsg);
- expect_seqnum++;
- check_queue();
- } else {
- dbg("timeout event for unexpected sequence number %d", pmsg->seqnum);
- }
+ dbg("current sequence %d, expected sequence %d", msg->seqnum, expect_seqnum);
+ if (msg->seqnum == expect_seqnum) {
+ /* execute expected event */
+ dispatch_msg(msg);
+ expect_seqnum++;
+ check_queue();
+ dump_queue();
+ continue;
}
+ if (msg->seqnum > expect_seqnum) {
+ /* something missing, queue event*/
+ queue_msg(msg);
+ check_queue();
+ dump_queue();
+ continue;
+ }
+ dbg("too late for event with sequence %d, even skipped ", msg->seqnum);
} else {
if (errno == EINTR) {
- if (head != NULL) {
- /* event timeout, skip all missing, proceed with next queued event */
- info("timeout reached, skip events %d - %d", expect_seqnum, head->seqnum-1);
- expect_seqnum = head->seqnum;
- } else {
+ /* timeout */
+ if (list_empty(&msg_list)) {
info("we have nothing to do, so daemon exits...");
if (lock_file >= 0) {
close(lock_file);
exit(0);
}
check_queue();
- } else {
- dbg("ipc message receive error '%s'", strerror(errno));
+ dump_queue();
+ continue;
}
+ dbg("ipc message receive error '%s'", strerror(errno));
}
}
- return 0;
-}
-
-static void sig_handler(int signum)
-{
- dbg("caught signal %d", signum);
- switch (signum) {
- case SIGINT:
- case SIGTERM:
- case SIGKILL:
- if (lock_file >= 0) {
- close(lock_file);
- unlink(lock_filename);
- }
- exit(20 + signum);
- break;
-
- default:
- dbg("unhandled signal");
- }
}
static int one_and_only(void)
/* see if we can open */
if (lock_file < 0)
- return -EINVAL;
+ return -1;
/* see if we can lock */
if (lockf(lock_file, F_TLOCK, 0) < 0) {
close(lock_file);
unlink(lock_filename);
- return -EINVAL;
+ return -1;
}
snprintf(string, sizeof(string), "%d\n", getpid());
write(lock_file, string, strlen(string));
-
+
return 0;
}
signal(SIGINT, sig_handler);
signal(SIGTERM, sig_handler);
signal(SIGKILL, sig_handler);
+ signal(SIGALRM, sig_handler);
/* we exit if we have nothing to do, next event will start us again */
- set_timer(DAEMON_TIMEOUT_SECONDS);
+ set_timeout(UDEVD_TIMEOUT_SECONDS);
- /* main loop */
- process_queue();
- return 0;
+ work();
+ exit(0);
}
projects / systemd / commitdiff