allow rules to have labels and skip to next label

This will allow us to have whole blocks of rules to skip
conditionally. The following section creates the node "yes":
  GOTO="TEST"
  NAME="no"
  NAME="no2", LABEL="NO"
  NAME="yes", LABEL="TEST"
  NAME="no3"

Makefile

@@ -377,8 +377,8 @@ install: install-config install-man all
 	$(INSTALL_PROGRAM) -D $(STARTER) $(DESTDIR)$(sbindir)/$(STARTER)
 ifndef DESTDIR
 	- killall $(DAEMON)
-	- $(sbindir)/$(DAEMON) --daemon
 	- rm -rf $(udevdb)
+	- $(sbindir)/$(DAEMON) --daemon
 endif
 	@extras="$(EXTRAS)" ; for target in $$extras ; do \
 		echo $$target ; \

test/udev-test.pl

@@ -1492,6 +1492,19 @@ EOF
 		option		=> "clean",
 		rules		=> <<EOF
 KERNEL=="sda1", IMPORT{parent}="PARENT*", NAME="parentenv-\$env{PARENT_KEY}\$env{WRONG_PARENT_KEY}"
+EOF
+	},
+	{
+		desc		=> "GOTO test",
+		subsys		=> "block",
+		devpath		=> "/block/sda/sda1",
+		exp_name	=> "right",
+		rules		=> <<EOF
+KERNEL=="sda1", GOTO="TEST"
+KERNEL=="sda1", NAME="wrong"
+KERNEL=="sda1", NAME="", LABEL="NO"
+KERNEL=="sda1", NAME="right", LABEL="TEST"
+KERNEL=="sda1", NAME="wrong2"
 EOF
 	},
 );

udev_rules.c

@@ -1069,6 +1069,11 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev, struct s
 				dbg("last rule to be applied");
 				break;
 			}
+
+			if (rule->goto_label.operation != KEY_OP_UNSET) {
+				dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
+				udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
+			}
 		}
 	}
 

udev_rules.h

@@ -62,6 +62,8 @@ enum import_type {
 };
 
 struct udev_rule {
+	struct key label;
+	struct key goto_label;
 	struct key kernel_name;
 	struct key subsystem;
 	struct key action;
@@ -108,6 +110,7 @@ extern void udev_rules_close(struct udev_rules *rules);
 
 extern void udev_rules_iter_init(struct udev_rules *rules);
 extern struct udev_rule *udev_rules_iter_next(struct udev_rules *rules);
+extern struct udev_rule *udev_rules_iter_label(struct udev_rules *rules, const char *label);
 
 extern int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev, struct sysfs_class_device *class_dev);
 extern int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev, struct sysfs_device *sysfs_device);

udev_rules_parse.c

@@ -52,8 +52,10 @@ struct udev_rule *udev_rules_iter_next(struct udev_rules *rules)
 		return NULL;
 
 	dbg("current=%zi", rules->current);
-	if (rules->current >= rules->bufsize)
+	if (rules->current >= rules->bufsize) {
+		dbg("no more rules");
 		return NULL;
+	}
 
 	/* get next rule */
 	rule = (struct udev_rule *) (rules->buf + rules->current);
@@ -62,6 +64,28 @@ struct udev_rule *udev_rules_iter_next(struct udev_rules *rules)
 	return rule;
 }
 
+struct udev_rule *udev_rules_iter_label(struct udev_rules *rules, const char *label)
+{
+	static struct udev_rule *rule;
+
+next:
+	dbg("current=%zi", rules->current);
+	if (rules->current >= rules->bufsize) {
+		dbg("no more rules");
+		return NULL;
+	}
+	rule = (struct udev_rule *) (rules->buf + rules->current);
+
+	if (strcmp(&rule->buf[rule->label.val_off], label) != 0) {
+		dbg("moving forward, looking for label '%s'", label);
+		rules->current += sizeof(struct udev_rule) + rule->bufsize;
+		goto next;
+	}
+
+	dbg("found label '%s'", label);
+	return rule;
+}
+
 static int get_key(char **line, char **key, enum key_operation *operation, char **value)
 {
 	char *linepos;
@@ -237,6 +261,18 @@ static int add_to_rules(struct udev_rules *rules, char *line)
 		if (retval)
 			break;
 
+		if (strcasecmp(key, "LABEL") == 0) {
+			add_rule_key(rule, &rule->label, operation, value);
+			valid = 1;
+			continue;
+		}
+
+		if (strcasecmp(key, "GOTO") == 0) {
+			add_rule_key(rule, &rule->goto_label, operation, value);
+			valid = 1;
+			continue;
+		}
+
 		if (strcasecmp(key, "KERNEL") == 0) {
 			add_rule_key(rule, &rule->kernel_name, operation, value);
 			valid = 1;
@@ -475,6 +511,7 @@ static int add_to_rules(struct udev_rules *rules, char *line)
 		err("realloc failed");
 		goto exit;
 	}
+	dbg("adding rule to offset %zi", rules->bufsize);
 	memcpy(rules->buf + rules->bufsize, rule, rule_size);
 	rules->bufsize += rule_size;
 exit: