From: Ben Pfaff Date: Thu, 12 Jul 2012 17:13:10 +0000 (-0700) Subject: classifier: New function cls_rule_is_loose_match(). X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6ceeaa926d9cb325d963da0c6f03bcc3b98c0344;p=openvswitch classifier: New function cls_rule_is_loose_match(). This function will be useful in an upcoming commit. Signed-off-by: Ben Pfaff --- diff --git a/lib/classifier.c b/lib/classifier.c index 6e8f4d2b..2d9fd0a9 100644 --- a/lib/classifier.c +++ b/lib/classifier.c @@ -934,6 +934,47 @@ classifier_rule_overlaps(const struct classifier *cls, return false; } + +/* Returns true if 'rule' exactly matches 'criteria' or if 'rule' is more + * specific than 'criteria'. That is, 'rule' matches 'criteria' and this + * function returns true if, for every field: + * + * - 'criteria' and 'rule' specify the same (non-wildcarded) value for the + * field, or + * + * - 'criteria' wildcards the field, + * + * Conversely, 'rule' does not match 'criteria' and this function returns false + * if, for at least one field: + * + * - 'criteria' and 'rule' specify different values for the field, or + * + * - 'criteria' specifies a value for the field but 'rule' wildcards it. + * + * Equivalently, the truth table for whether a field matches is: + * + * rule + * + * c wildcard exact + * r +---------+---------+ + * i wild | yes | yes | + * t card | | | + * e +---------+---------+ + * r exact | no |if values| + * i | |are equal| + * a +---------+---------+ + * + * This is the matching rule used by OpenFlow 1.0 non-strict OFPT_FLOW_MOD + * commands and by OpenFlow 1.0 aggregate and flow stats. + * + * Ignores rule->priority and criteria->priority. */ +bool +cls_rule_is_loose_match(const struct cls_rule *rule, + const struct cls_rule *criteria) +{ + return (!flow_wildcards_has_extra(&rule->wc, &criteria->wc) + && flow_equal_except(&rule->flow, &criteria->flow, &criteria->wc)); +} /* Iteration. */ @@ -959,40 +1000,14 @@ search_table(const struct cls_table *table, const struct cls_rule *target) return NULL; } -/* Initializes 'cursor' for iterating through 'cls' rules that exactly match - * 'target' or are more specific than 'target'. That is, a given 'rule' - * matches 'target' if, for every field: - * - * - 'target' and 'rule' specify the same (non-wildcarded) value for the - * field, or - * - * - 'target' wildcards the field, - * - * but not if: - * - * - 'target' and 'rule' specify different values for the field, or - * - * - 'target' specifies a value for the field but 'rule' wildcards it. +/* Initializes 'cursor' for iterating through rules in 'cls': * - * Equivalently, the truth table for whether a field matches is: - * - * rule - * - * wildcard exact - * +---------+---------+ - * t wild | yes | yes | - * a card | | | - * r +---------+---------+ - * g exact | no |if values| - * e | |are equal| - * t +---------+---------+ - * - * This is the matching rule used by OpenFlow 1.0 non-strict OFPT_FLOW_MOD - * commands and by OpenFlow 1.0 aggregate and flow stats. + * - If 'target' is null, the cursor will visit every rule in 'cls'. * - * Ignores target->priority. + * - If 'target' is nonnull, the cursor will visit each 'rule' in 'cls' + * such that cls_rule_is_loose_match(rule, target) returns true. * - * 'target' may be NULL to iterate over every rule in 'cls'. */ + * Ignores target->priority. */ void cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls, const struct cls_rule *target) diff --git a/lib/classifier.h b/lib/classifier.h index ec7316cd..b154899d 100644 --- a/lib/classifier.h +++ b/lib/classifier.h @@ -87,6 +87,9 @@ void cls_rule_init_catchall(struct cls_rule *, unsigned int priority); void cls_rule_zero_wildcarded_fields(struct cls_rule *); +bool cls_rule_is_loose_match(const struct cls_rule *rule, + const struct cls_rule *criteria); + void cls_rule_set_reg(struct cls_rule *, unsigned int reg_idx, uint32_t value); void cls_rule_set_reg_masked(struct cls_rule *, unsigned int reg_idx, uint32_t value, uint32_t mask);