update README

[elogind.git] / udevd.c

diff --git a/udevd.c b/udevd.c
index 110d8e7c4d3a3fe90f547f76e252dbba63f0a0e8..d51ed2f7b0d98cdfe45364476fb9b954e9122952 100644 (file)
--- a/udevd.c
+++ b/udevd.c
@@ -1,5 +1,5 @@
 /*
- * udevd.c - hotplug event serializer
+ * udevd.c - event listener and serializer
  *
  * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
  * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
@@ -38,6 +38,7 @@
 #include <sys/un.h>
 #include <sys/sysinfo.h>
 #include <sys/stat.h>
+#include <linux/types.h>
 #include <linux/netlink.h>
 
 #include "list.h"
@@ -48,10 +49,6 @@
 #include "udevd.h"
 #include "logging.h"
 
-#ifndef NETLINK_KOBJECT_UEVENT
-#define NETLINK_KOBJECT_UEVENT 15
-#endif
-
 /* global variables*/
 static int udevd_sock;
 static int uevent_netlink_sock;
@@ -61,6 +58,7 @@ static int pipefds[2];
 static volatile int sigchilds_waiting;
 static volatile int run_msg_q;
 static volatile int sig_flag;
+static volatile int udev_exit;
 static int init_phase = 1;
 static int run_exec_q;
 static int stop_exec_q;
@@ -644,23 +642,20 @@ static void asmlinkage sig_handler(int signum)
        switch (signum) {
                case SIGINT:
                case SIGTERM:
-                       exit(20 + signum);
+                       udev_exit = 1;
                        break;
                case SIGALRM:
                        /* set flag, then write to pipe if needed */
                        run_msg_q = 1;
-                       goto do_write;
                        break;
                case SIGCHLD:
                        /* set flag, then write to pipe if needed */
                        sigchilds_waiting = 1;
-                       goto do_write;
                        break;
        }
 
-do_write:
-       /* if pipe is empty, write to pipe to force select to return
-        * immediately when it gets called
+       /* if pipe is empty, write to pipe to force select to return,
+        * which will wakeup our mainloop
         */
        if (!sig_flag) {
                rc = write(pipefds[1],&signum,sizeof(signum));
@@ -842,7 +837,7 @@ int main(int argc, char *argv[], char *envp[])
        chdir("/");
        umask(umask(077) | 022);
 
-       /*set a reasonable scheduling priority for the daemon */
+       /* set a reasonable scheduling priority for the daemon */
        setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
        /* Set fds to dev/null */
@@ -890,6 +885,7 @@ int main(int argc, char *argv[], char *envp[])
        sigaction(SIGTERM, &act, NULL);
        sigaction(SIGALRM, &act, NULL);
        sigaction(SIGCHLD, &act, NULL);
+       sigaction(SIGHUP, &act, NULL);
 
        if (init_uevent_netlink_sock() < 0) {
                dbg("uevent socket not available");
@@ -944,11 +940,11 @@ int main(int argc, char *argv[], char *envp[])
 
        FD_ZERO(&readfds);
        FD_SET(udevd_sock, &readfds);
-       if (uevent_netlink_sock != -1)
+       if (uevent_netlink_sock > 0)
                FD_SET(uevent_netlink_sock, &readfds);
        FD_SET(pipefds[0], &readfds);
        maxsockplus = udevd_sock+1;
-       while (1) {
+       while (!udev_exit) {
                struct uevent_msg *msg;
 
                fd_set workreadfds = readfds;
@@ -960,6 +956,7 @@ int main(int argc, char *argv[], char *envp[])
                        continue;
                }
 
+               /* get user socket message */
                if (FD_ISSET(udevd_sock, &workreadfds)) {
                        msg = get_udevd_msg();
                        if (msg) {
@@ -973,6 +970,7 @@ int main(int argc, char *argv[], char *envp[])
                        }
                }
 
+               /* get kernel netlink message */
                if (FD_ISSET(uevent_netlink_sock, &workreadfds)) {
                        msg = get_netlink_msg();
                        if (msg) {
@@ -985,9 +983,11 @@ int main(int argc, char *argv[], char *envp[])
                        }
                }
 
+               /* received a signal, clear our notification pipe */
                if (FD_ISSET(pipefds[0], &workreadfds))
                        user_sighandler();
 
+               /* forked child have returned */
                if (sigchilds_waiting) {
                        sigchilds_waiting = 0;
                        reap_sigchilds();
@@ -1012,6 +1012,13 @@ int main(int argc, char *argv[], char *envp[])
        }
 
 exit:
+       if (udevd_sock > 0)
+               close(udevd_sock);
+
+       if (uevent_netlink_sock > 0)
+               close(uevent_netlink_sock);
+
        logging_close();
-       return 1;
+
+       return 0;
 }