udevd: read debug settings from kernel commandline

libudev/libudev-util.c

@@ -87,13 +87,13 @@ int util_log_priority(const char *priority)
 	int prio;
 
 	prio = strtol(priority, &endptr, 10);
-	if (endptr[0] == '\0')
+	if (endptr[0] == '\0' || isspace(endptr[0]))
 		return prio;
 	if (strncmp(priority, "err", 3) == 0)
 		return LOG_ERR;
-	if (strcmp(priority, "info") == 0)
+	if (strncmp(priority, "info", 4) == 0)
 		return LOG_INFO;
-	if (strcmp(priority, "debug") == 0)
+	if (strncmp(priority, "debug", 5) == 0)
 		return LOG_DEBUG;
 	return 0;
 }

udev/udev-event.c

@@ -681,6 +681,10 @@ int udev_event_execute_run(struct udev_event *event, const sigset_t *sigmask)
 
 			udev_event_apply_format(event, cmd, program, sizeof(program));
 			envp = udev_device_get_properties_envp(event->dev);
+			if (event->exec_delay > 0) {
+				info(event->udev, "delay execution of '%s'\n", program);
+				sleep(event->exec_delay);
+			}
 			if (util_run_program(event->udev, program, envp, NULL, 0, NULL, sigmask, true) != 0) {
 				if (udev_list_entry_get_flags(list_entry))
 					err = -1;

udev/udev.h

@@ -43,6 +43,7 @@ struct udev_event {
 	uid_t uid;
 	gid_t gid;
 	struct udev_list_node run_list;
+	int exec_delay;
 	bool group_final;
 	bool owner_final;
 	bool mode_final;

udev/udevd.c

@@ -79,6 +79,7 @@ static bool stop_exec_queue;
 static bool reload_config;
 static int children;
 static int children_max;
+static int exec_delay;
 static sigset_t orig_sigmask;
 static struct udev_list_node event_list;
 static struct udev_list_node worker_list;
@@ -285,6 +286,9 @@ static void worker_new(struct event *event)
 			/* set timeout to prevent hanging processes */
 			alarm(UDEV_EVENT_TIMEOUT);
 
+			if (exec_delay > 0)
+				udev_event->exec_delay = exec_delay;
+
 			/* apply rules, create node, symlinks */
 			err = udev_event_execute_rules(udev_event, rules);
 
@@ -386,7 +390,8 @@ static void event_run(struct event *event, bool force)
 	}
 
 	if (!force && children >= children_max) {
-		info(event->udev, "maximum number (%i) of children reached\n", children);
+		if (children_max > 1)
+			info(event->udev, "maximum number (%i) of children reached\n", children);
 		return;
 	}
 
@@ -957,6 +962,7 @@ int main(int argc, char *argv[])
 		{ "daemon", no_argument, NULL, 'd' },
 		{ "debug", no_argument, NULL, 'D' },
 		{ "children-max", required_argument, NULL, 'c' },
+		{ "exec-delay", required_argument, NULL, 'e' },
 		{ "resolve-names", required_argument, NULL, 'N' },
 		{ "help", no_argument, NULL, 'h' },
 		{ "version", no_argument, NULL, 'V' },
@@ -976,7 +982,7 @@ int main(int argc, char *argv[])
 	for (;;) {
 		int option;
 
-		option = getopt_long(argc, argv, "dDthV", options, NULL);
+		option = getopt_long(argc, argv, "cdeDthV", options, NULL);
 		if (option == -1)
 			break;
 
@@ -985,7 +991,10 @@ int main(int argc, char *argv[])
 			daemonize = true;
 			break;
 		case 'c':
-			children_max = strtoul(optarg, NULL, 10);
+			children_max = strtoul(optarg, NULL, 0);
+			break;
+		case 'e':
+			exec_delay = strtoul(optarg, NULL, 0);
 			break;
 		case 'D':
 			debug = true;
@@ -1006,8 +1015,15 @@ int main(int argc, char *argv[])
 			}
 			break;
 		case 'h':
-			printf("Usage: udevd [--help] [--daemon] [--children-max] [--debug] "
-			       "[--resolve-names=early|late|never] [--version]\n");
+			printf("Usage: udevd OPTIONS\n"
+			       "  --daemon\n"
+			       "  --debug\n"
+			       "  --children-max=<maximum number of workers>\n"
+			       "  --exec-delay=<seconds to wait before executing RUN=>\n"
+			       "  --resolve-names=early|late|never\n" 
+			       "  --version\n"
+			       "  --help\n"
+			       "\n");
 			goto exit;
 		case 'V':
 			printf("%s\n", VERSION);
@@ -1023,6 +1039,40 @@ int main(int argc, char *argv[])
 		goto exit;
 	}
 
+	/*
+	 * read the kernel commandline, in case we need to get into debug mode
+	 *   udev.log-priority=<level>              syslog priority
+	 *   udev.children-max=<number of workers>  events are fully serialized if set to 1
+	 *
+	 */
+	f = fopen("/proc/cmdline", "r");
+	if (f != NULL) {
+		char cmdline[4096];
+
+		if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
+			char *pos;
+
+			pos = strstr(cmdline, "udev.log-priority=");
+			if (pos != NULL) {
+				pos += strlen("udev.log-priority=");
+				udev_set_log_priority(udev, util_log_priority(pos));
+			}
+
+			pos = strstr(cmdline, "udev.children-max=");
+			if (pos != NULL) {
+				pos += strlen("udev.children-max=");
+				children_max = strtoul(pos, NULL, 0);
+			}
+
+			pos = strstr(cmdline, "udev.exec-delay=");
+			if (pos != NULL) {
+				pos += strlen("udev.exec-delay=");
+				exec_delay = strtoul(pos, NULL, 0);
+			}
+		}
+		fclose(f);
+	}
+
 	/* make sure std{in,out,err} fds are in a sane state */
 	fd = open("/dev/null", O_RDWR);
 	if (fd < 0) {
@@ -1172,19 +1222,13 @@ int main(int argc, char *argv[])
 	}
 
 	if (children_max <= 0) {
-		const char *value = getenv("UDEVD_CHILDREN_MAX");
+		int memsize = mem_size_mb();
 
-		if (value) {
-			children_max = strtoul(value, NULL, 10);
-		} else {
-			int memsize = mem_size_mb();
-
-			/* set value depending on the amount of RAM */
-			if (memsize > 0)
-				children_max = 128 + (memsize / 8);
-			else
-				children_max = 128;
-		}
+		/* set value depending on the amount of RAM */
+		if (memsize > 0)
+			children_max = 128 + (memsize / 8);
+		else
+			children_max = 128;
 	}
 	info(udev, "set children_max to %u\n", children_max);