X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev%2Fudevadm-monitor.c;h=10b2f2e71b8c1ce0f2d4b49f153bcb30342b7115;hp=01126c99517b42331e2da3dc6714d77500aa648d;hb=dacea9ff6be55f1b115c13b1ab530812d0d66879;hpb=0de33a61d741699f41f47ebdb505f518722159b2

diff --git a/udev/udevadm-monitor.c b/udev/udevadm-monitor.c
index 01126c995..10b2f2e71 100644
--- a/udev/udevadm-monitor.c
+++ b/udev/udevadm-monitor.c
@@ -71,21 +71,24 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 	int env = 0;
 	int print_kernel = 0;
 	int print_udev = 0;
+	struct udev_list_node subsystem_match_list;
 	struct udev_monitor *udev_monitor = NULL;
 	struct udev_monitor *kernel_monitor = NULL;
 	fd_set readfds;
 	int rc = 0;
 
 	static const struct option options[] = {
-		{ "environment", 0, NULL, 'e' },
-		{ "kernel", 0, NULL, 'k' },
-		{ "udev", 0, NULL, 'u' },
-		{ "help", 0, NULL, 'h' },
+		{ "environment", no_argument, NULL, 'e' },
+		{ "kernel", no_argument, NULL, 'k' },
+		{ "udev", no_argument, NULL, 'u' },
+		{ "subsystem-match", required_argument, NULL, 's' },
+		{ "help", no_argument, NULL, 'h' },
 		{}
 	};
 
+	udev_list_init(&subsystem_match_list);
 	while (1) {
-		option = getopt_long(argc, argv, "ekuh", options, NULL);
+		option = getopt_long(argc, argv, "ekus:h", options, NULL);
 		if (option == -1)
 			break;
 
@@ -99,12 +102,15 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 		case 'u':
 			print_udev = 1;
 			break;
+		case 's':
+			udev_list_entry_add(udev, &subsystem_match_list, optarg, NULL, 1, 0);
+			break;
 		case 'h':
 			printf("Usage: udevadm monitor [--environment] [--kernel] [--udev] [--help]\n"
 			       "  --env    print the whole event environment\n"
 			       "  --kernel print kernel uevents\n"
 			       "  --udev   print udev events\n"
-			       "  --help   print this help text\n\n");
+			       "  --help\n\n");
 		default:
 			goto out;
 		}
@@ -115,11 +121,6 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 		print_udev =1;
 	}
 
-	if (getuid() != 0 && print_kernel) {
-		fprintf(stderr, "root privileges needed to subscribe to kernel events\n");
-		goto out;
-	}
-
 	/* set signal handlers */
 	memset(&act, 0x00, sizeof(struct sigaction));
 	act.sa_handler = (void (*)(int)) sig_handler;
@@ -130,28 +131,42 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 
 	printf("monitor will print the received events for:\n");
 	if (print_udev) {
-		udev_monitor = udev_monitor_new_from_socket(udev, "@/org/kernel/udev/monitor");
+		struct udev_list_entry *entry;
+
+		udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
 		if (udev_monitor == NULL) {
+			fprintf(stderr, "error: unable to create netlink socket\n");
 			rc = 1;
 			goto out;
 		}
+
+		udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
+			const char *subsys = udev_list_entry_get_name(entry);
+
+			if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, subsys, NULL) < 0)
+				fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
+		}
+
 		if (udev_monitor_enable_receiving(udev_monitor) < 0) {
+			fprintf(stderr, "error: unable to subscribe to udev events\n");
 			rc = 2;
 			goto out;
 		}
-		printf("UDEV the event which udev sends out after rule processing\n");
+		printf("UDEV - the event which udev sends out after rule processing\n");
 	}
 	if (print_kernel) {
-		kernel_monitor = udev_monitor_new_from_netlink(udev);
+		kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
 		if (kernel_monitor == NULL) {
+			fprintf(stderr, "error: unable to create netlink socket\n");
 			rc = 3;
 			goto out;
 		}
 		if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
+			fprintf(stderr, "error: unable to subscribe to kernel events\n");
 			rc = 4;
 			goto out;
 		}
-		printf("UEVENT the kernel uevent\n");
+		printf("KERNEL - the kernel uevent\n");
 	}
 	printf("\n");
 
@@ -168,7 +183,7 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 				 &readfds, NULL, NULL, NULL);
 		if (fdcount < 0) {
 			if (errno != EINTR)
-				fprintf(stderr, "error receiving uevent message: %s\n", strerror(errno));
+				fprintf(stderr, "error receiving uevent message: %m\n");
 			continue;
 		}
 
@@ -178,7 +193,7 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 			device = udev_monitor_receive_device(kernel_monitor);
 			if (device == NULL)
 				continue;
-			print_device(device, "UEVENT", env);
+			print_device(device, "KERNEL", env);
 			udev_device_unref(device);
 		}
 
@@ -196,5 +211,6 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 out:
 	udev_monitor_unref(udev_monitor);
 	udev_monitor_unref(kernel_monitor);
+	udev_list_cleanup_entries(udev, &subsystem_match_list);
 	return rc;
 }