consistent key naming to match only the event device or include all parent devices

This scheme is more consistent and makes it obvious if a match happens
against the event device only, or the full chain of parent devices.

The old key names are now:
  BUS -> SUBSYSTEMS
  ID -> KERNELS
  SYSFS -> ATTRS
  DRIVER -> DRIVERS

Match keys for the event device:
  KERNEL
  SUBSYSTEM
  ATTR
  DRIVER (in a future release, for now the same as DRIVERS)

Match keys for all devices along the parent device chain:
  KERNELS
  SUBSYSTEMS
  ATTRS
  DRIVERS

ID, BUS, SYSFS are no longer mentioned in the man page but still work.
DRIVER must be converted to DRIVERS to match the new scheme. For now,
an error is logged, if DRIVER is used. In a future release, the DRIVER
key behaviour will change.

1 files changed, 80 insertions, 45 deletions

diff --git a/udev_rules.c b/udev_rules.c
index 979b81d821..49306295ff 100644
--- a/udev_rules.c
+++ b/udev_rules.c
@@ -307,13 +307,13 @@ void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
 	enum subst_type {
 		SUBST_UNKNOWN,
 		SUBST_DEVPATH,
+		SUBST_KERNEL,
 		SUBST_KERNEL_NUMBER,
-		SUBST_KERNEL_NAME,
 		SUBST_ID,
 		SUBST_MAJOR,
 		SUBST_MINOR,
 		SUBST_RESULT,
-		SUBST_SYSFS,
+		SUBST_ATTR,
 		SUBST_PARENT,
 		SUBST_TEMP_NODE,
 		SUBST_ROOT,
@@ -324,18 +324,19 @@ void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
 		char fmt;
 		enum subst_type type;
 	} map[] = {
-		{ .name = "devpath",		.fmt = 'p',	.type = SUBST_DEVPATH },
-		{ .name = "number",		.fmt = 'n',	.type = SUBST_KERNEL_NUMBER },
-		{ .name = "kernel",		.fmt = 'k',	.type = SUBST_KERNEL_NAME },
-		{ .name = "id",			.fmt = 'b',	.type = SUBST_ID },
-		{ .name = "major",		.fmt = 'M',	.type = SUBST_MAJOR },
-		{ .name = "minor",		.fmt = 'm',	.type = SUBST_MINOR },
-		{ .name = "result",		.fmt = 'c',	.type = SUBST_RESULT },
-		{ .name = "sysfs",		.fmt = 's',	.type = SUBST_SYSFS },
-		{ .name = "parent",		.fmt = 'P',	.type = SUBST_PARENT },
-		{ .name = "tempnode",		.fmt = 'N',	.type = SUBST_TEMP_NODE },
-		{ .name = "root",		.fmt = 'r',	.type = SUBST_ROOT },
-		{ .name = "env",		.fmt = 'E',	.type = SUBST_ENV },
+		{ .name = "devpath",	.fmt = 'p',	.type = SUBST_DEVPATH },
+		{ .name = "number",	.fmt = 'n',	.type = SUBST_KERNEL_NUMBER },
+		{ .name = "kernel",	.fmt = 'k',	.type = SUBST_KERNEL },
+		{ .name = "id",		.fmt = 'b',	.type = SUBST_ID },
+		{ .name = "major",	.fmt = 'M',	.type = SUBST_MAJOR },
+		{ .name = "minor",	.fmt = 'm',	.type = SUBST_MINOR },
+		{ .name = "result",	.fmt = 'c',	.type = SUBST_RESULT },
+		{ .name = "attr",	.fmt = 's',	.type = SUBST_ATTR },
+		{ .name = "sysfs",	.fmt = 's',	.type = SUBST_ATTR },
+		{ .name = "parent",	.fmt = 'P',	.type = SUBST_PARENT },
+		{ .name = "tempnode",	.fmt = 'N',	.type = SUBST_TEMP_NODE },
+		{ .name = "root",	.fmt = 'r',	.type = SUBST_ROOT },
+		{ .name = "env",	.fmt = 'E',	.type = SUBST_ENV },
 		{ NULL, '\0', 0 }
 	};
 	enum subst_type type;
@@ -399,9 +400,9 @@ found:
 			strlcat(string, udev->dev->devpath, maxsize);
 			dbg("substitute devpath '%s'", udev->dev->devpath);
 			break;
-		case SUBST_KERNEL_NAME:
-			strlcat(string, udev->dev->kernel_name, maxsize);
-			dbg("substitute kernel name '%s'", udev->dev->kernel_name);
+		case SUBST_KERNEL:
+			strlcat(string, udev->dev->kernel, maxsize);
+			dbg("substitute kernel name '%s'", udev->dev->kernel);
 			break;
 		case SUBST_KERNEL_NUMBER:
 			strlcat(string, udev->dev->kernel_number, maxsize);
@@ -409,8 +410,8 @@ found:
 			break;
 		case SUBST_ID:
 			if (udev->dev_parent != NULL) {
-				strlcat(string, udev->dev_parent->kernel_name, maxsize);
-				dbg("substitute id '%s'", udev->dev_parent->kernel_name);
+				strlcat(string, udev->dev_parent->kernel, maxsize);
+				dbg("substitute id '%s'", udev->dev_parent->kernel);
 			}
 			break;
 		case SUBST_MAJOR:
@@ -457,7 +458,7 @@ found:
 				dbg("substitute result string '%s'", udev->program_result);
 			}
 			break;
-		case SUBST_SYSFS:
+		case SUBST_ATTR:
 			if (attr == NULL) {
 				dbg("missing attribute");
 				break;
@@ -605,7 +606,7 @@ static int match_rule(struct udevice *udev, struct udev_rule *rule)
 	if (match_key("ACTION", rule, &rule->action, udev->action))
 		goto nomatch;
 
-	if (match_key("KERNEL", rule, &rule->kernel_name, udev->dev->kernel_name))
+	if (match_key("KERNEL", rule, &rule->kernel, udev->dev->kernel))
 		goto nomatch;
 
 	if (match_key("SUBSYSTEM", rule, &rule->subsystem, udev->dev->subsystem))
@@ -614,7 +615,10 @@ static int match_rule(struct udevice *udev, struct udev_rule *rule)
 	if (match_key("DEVPATH", rule, &rule->devpath, udev->dev->devpath))
 		goto nomatch;
 
-	/* compare NAME against a previously assigned value */
+	if (match_key("DRIVER", rule, &rule->driver, udev->dev->driver))
+		goto nomatch;
+
+	/* match NAME against a value assigned by an earlier rule */
 	if (match_key("NAME", rule, &rule->name, udev->name))
 		goto nomatch;
 
@@ -646,26 +650,57 @@ static int match_rule(struct udevice *udev, struct udev_rule *rule)
 		}
 	}
 
+	/* check for matching sysfs attrubute pairs */
+	if (rule->attr.count) {
+		dbg("check %i ATTR keys", rule->attr.count);
+		for (i = 0; i < rule->attr.count; i++) {
+			struct key_pair *pair = &rule->attr.keys[i];
+			const char *key_name = key_pair_name(rule, pair);
+			const char *key_value = key_val(rule, &pair->key);
+			const char *value;
+			char val[VALUE_SIZE];
+			size_t len;
+
+			value = sysfs_attr_get_value(udev->dev->devpath, key_name);
+			if (value == NULL)
+				goto nomatch;
+			strlcpy(val, value, sizeof(val));
+
+			/* strip trailing whitespace of value, if not asked to match for it */
+			len = strlen(key_value);
+			if (len > 0 && !isspace(key_value[len-1])) {
+				len = strlen(val);
+				while (len > 0 && isspace(val[len-1]))
+					val[--len] = '\0';
+				dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
+			}
+
+			if (match_key("ATTR", rule, &pair->key, val))
+				goto nomatch;
+		}
+		dbg("all %i ATTR keys matched", rule->attr.count);
+	}
+
 	/* walk up the chain of parent devices and find a match */
 	udev->dev_parent = udev->dev;
 	while (1) {
-		/* check for matching driver */
-		if (match_key("DRIVER", rule, &rule->driver, udev->dev_parent->driver))
+		/* check for matching kernel device name */
+		if (match_key("KERNELS", rule, &rule->kernels, udev->dev_parent->kernel))
 			goto try_parent;
 
-		/* check for matching subsystem/bus value */
-		if (match_key("BUS", rule, &rule->bus, udev->dev_parent->subsystem))
+		/* check for matching subsystem value */
+		if (match_key("SUBSYSTEMS", rule, &rule->subsystems, udev->dev_parent->subsystem))
 			goto try_parent;
 
-		/* check for matching bus id (device name) */
-		if (match_key("ID", rule, &rule->id, udev->dev_parent->kernel_name))
+		/* check for matching driver */
+		if (match_key("DRIVERS", rule, &rule->drivers, udev->dev_parent->driver))
 			goto try_parent;
 
-		/* check for matching sysfs pairs */
-		if (rule->sysfs.count) {
-			dbg("check %i SYSFS keys", rule->sysfs.count);
-			for (i = 0; i < rule->sysfs.count; i++) {
-				struct key_pair *pair = &rule->sysfs.keys[i];
+		/* check for matching sysfs attrubute pairs */
+		if (rule->attrs.count) {
+			dbg("check %i ATTRS keys", rule->attrs.count);
+			for (i = 0; i < rule->attrs.count; i++) {
+				struct key_pair *pair = &rule->attrs.keys[i];
 				const char *key_name = key_pair_name(rule, pair);
 				const char *key_value = key_val(rule, &pair->key);
 				const char *value;
@@ -688,10 +723,10 @@ static int match_rule(struct udevice *udev, struct udev_rule *rule)
 					dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
 				}
 
-				if (match_key("SYSFS", rule, &pair->key, val))
+				if (match_key("ATTRS", rule, &pair->key, val))
 					goto try_parent;
 			}
-			dbg("all %i SYSFS keys matched", rule->sysfs.count);
+			dbg("all %i ATTRS keys matched", rule->attrs.count);
 		}
 
 		/* found matching device  */
@@ -703,7 +738,7 @@ try_parent:
 		if (udev->dev_parent == NULL)
 			goto nomatch;
 		dbg("looking at dev_parent->devpath='%s'", udev->dev_parent->devpath);
-		dbg("looking at dev_parent->bus_kernel_name='%s'", udev->dev_parent->kernel_name);
+		dbg("looking at dev_parent->kernel='%s'", udev->dev_parent->kernel);
 	}
 
 	/* execute external program */
@@ -794,7 +829,7 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 	int name_set = 0;
 
 	dbg("udev->dev->devpath='%s'", udev->dev->devpath);
-	dbg("udev->dev->kernel_name='%s'", udev->dev->kernel_name);
+	dbg("udev->dev->kernel='%s'", udev->dev->kernel);
 
 	/* look for a matching rule to apply */
 	udev_rules_iter_init(rules);
@@ -815,7 +850,7 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 		if (match_rule(udev, rule) == 0) {
 			/* apply options */
 			if (rule->ignore_device) {
-				info("rule applied, '%s' is ignored", udev->dev->kernel_name);
+				info("rule applied, '%s' is ignored", udev->dev->kernel);
 				udev->ignore_device = 1;
 				return 0;
 			}
@@ -835,21 +870,21 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 				if (rule->mode_operation == KEY_OP_ASSIGN_FINAL)
 					udev->mode_final = 1;
 				udev->mode = rule->mode;
-				dbg("applied mode=%#o to '%s'", rule->mode, udev->dev->kernel_name);
+				dbg("applied mode=%#o to '%s'", rule->mode, udev->dev->kernel);
 			}
 			if (!udev->owner_final && rule->owner.operation != KEY_OP_UNSET) {
 				if (rule->owner.operation == KEY_OP_ASSIGN_FINAL)
 					udev->owner_final = 1;
 				strlcpy(udev->owner, key_val(rule, &rule->owner), sizeof(udev->owner));
 				udev_rules_apply_format(udev, udev->owner, sizeof(udev->owner));
-				dbg("applied owner='%s' to '%s'", udev->owner, udev->dev->kernel_name);
+				dbg("applied owner='%s' to '%s'", udev->owner, udev->dev->kernel);
 			}
 			if (!udev->group_final && rule->group.operation != KEY_OP_UNSET) {
 				if (rule->group.operation == KEY_OP_ASSIGN_FINAL)
 					udev->group_final = 1;
 				strlcpy(udev->group, key_val(rule, &rule->group), sizeof(udev->group));
 				udev_rules_apply_format(udev, udev->group, sizeof(udev->group));
-				dbg("applied group='%s' to '%s'", udev->group, udev->dev->kernel_name);
+				dbg("applied group='%s' to '%s'", udev->group, udev->dev->kernel);
 			}
 
 			/* collect symlinks */
@@ -904,7 +939,7 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 				if (count)
 					info("%i untrusted character(s) replaced", count);
 
-				info("rule applied, '%s' becomes '%s'", udev->dev->kernel_name, udev->name);
+				info("rule applied, '%s' becomes '%s'", udev->dev->kernel, udev->name);
 				if (strcmp(udev->dev->subsystem, "net") != 0)
 					dbg("name, '%s' is going to have owner='%s', group='%s', mode=%#o partitions=%i",
 					    udev->name, udev->owner, udev->group, udev->mode, udev->partitions);
@@ -934,7 +969,7 @@ int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 	}
 
 	if (!name_set) {
-		strlcpy(udev->name, udev->dev->kernel_name, sizeof(udev->name));
+		strlcpy(udev->name, udev->dev->kernel, sizeof(udev->name));
 		info("no node name set, will use kernel name '%s'", udev->name);
 	}
 
@@ -951,7 +986,7 @@ int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev)
 {
 	struct udev_rule *rule;
 
-	dbg("udev->kernel_name='%s'", udev->dev->kernel_name);
+	dbg("udev->kernel='%s'", udev->dev->kernel);
 
 	/* look for a matching rule to apply */
 	udev_rules_iter_init(rules);
@@ -969,7 +1004,7 @@ int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev)
 
 		if (match_rule(udev, rule) == 0) {
 			if (rule->ignore_device) {
-				info("rule applied, '%s' is ignored", udev->dev->kernel_name);
+				info("rule applied, '%s' is ignored", udev->dev->kernel);
 				udev->ignore_device = 1;
 				return 0;
 			}