X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=udevd.c;h=1575da8d5a3005c217f40431091a087bc6e59407;hb=903a36495f2c796f15464943ad26bfd76f548b6a;hp=110d8e7c4d3a3fe90f547f76e252dbba63f0a0e8;hpb=39e54555a961fa6c4c8e7d260a0e208439dc0cfa;p=elogind.git

diff --git a/udevd.c b/udevd.c
index 110d8e7c4..1575da8d5 100644
--- 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"
@@ -48,19 +49,16 @@
 #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;
 static pid_t sid;
 
-static int pipefds[2];
+static int pipefds[2] = {-1, -1};
 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));
@@ -842,17 +837,16 @@ 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 */
 	fd = open( "/dev/null", O_RDWR );
 	if (fd >= 0)  {
-		dup2(fd, 0);
-		dup2(fd, 1);
-		dup2(fd, 2);
-		if (fd > 2)
-			close(fd);
+		dup2(fd, STDIN_FILENO);
+		dup2(fd, STDOUT_FILENO);
+		dup2(fd, STDERR_FILENO);
+		close(fd);
 	} else
 		err("error opening /dev/null %s", strerror(errno));
 
@@ -890,6 +884,7 @@ 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 +939,11 @@ 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 +955,7 @@ 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 +969,7 @@ 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 +982,11 @@ 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 +1011,18 @@ int main(int argc, char *argv[], char *envp[])
 	}
 
 exit:
+	if (pipefds[0] > 0)
+		close(pipefds[0]);
+	if (pipefds[1] > 0)
+		close(pipefds[1]);
+
+	if (udevd_sock > 0)
+		close(udevd_sock);
+
+	if (uevent_netlink_sock > 0)
+		close(uevent_netlink_sock);
+
 	logging_close();
-	return 1;
+
+	return 0;
 }