[PATCH] udevd - switch socket path to abstract namespace

As Chris Friesen <chris_friesen@sympatico.ca> suggested, here we switch
the unix domains socket path to abstract namespace and get rid of the
socket file in the filesystem.

Hey, this was new to me today. So here a few words:
  Linux supports a abstract namespace for sockets. We don't need a
  physical file on the filesystem but only a unique string magically
  starting with the '\0' character.

  strace with real file:
    connect(3, {sa_family=AF_UNIX, path="/udev/.udevd.sock"}, 110)

  strace with abstract namespace:
    connect(3, {sa_family=AF_UNIX, path=@udevd}, 110)

1 files changed, 2 insertions, 4 deletions

diff --git a/udevd.c b/udevd.c
index f8b8c27ee4..24cf9c9a7c 100644
--- a/udevd.c
+++ b/udevd.c
@@ -325,7 +325,6 @@ static void sig_handler(int signum)
 		case SIGINT:
 		case SIGTERM:
 			unlink(UDEVD_LOCK);
-			unlink(UDEVD_SOCK);
 			exit(20 + signum);
 			break;
 		default:
@@ -378,9 +377,9 @@ int main(int argc, char *argv[])
 
 	memset(&saddr, 0x00, sizeof(saddr));
 	saddr.sun_family = AF_LOCAL;
-	strcpy(saddr.sun_path, UDEVD_SOCK);
+	/* use abstract namespace for socket path */
+	strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
 
-	unlink(UDEVD_SOCK);
 	ssock = socket(AF_LOCAL, SOCK_STREAM, 0);
 	if (ssock == -1) {
 		dbg("error getting socket");
@@ -426,6 +425,5 @@ int main(int argc, char *argv[])
 	}
 exit:
 	close(ssock);
-	unlink(UDEVD_SOCK);
 	exit(1);
 }