resolve: manage DnsAnswerItem with OrderedSet

Previously, we manage DnsAnswerItem by an array and Set,
The array was used for the order of the items, and the set is used to
dedup items.
Let's use OrderedSet, then we can simplify the logic.

This fixes dns_answer_remove_by_key() and dns_answer_remove_by_rr()
which makes the set in a broken state.

1 files changed, 41 insertions, 52 deletions

diff --git a/src/resolve/resolved-dns-answer.h b/src/resolve/resolved-dns-answer.h
index 3eb573b2c1..414c03192a 100644
--- a/src/resolve/resolved-dns-answer.h
+++ b/src/resolve/resolved-dns-answer.h
@@ -5,8 +5,8 @@ typedef struct DnsAnswer DnsAnswer;
 typedef struct DnsAnswerItem DnsAnswerItem;
 
 #include "macro.h"
+#include "ordered-set.h"
 #include "resolved-dns-rr.h"
-#include "set.h"
 
 /* A simple array of resource records. We keep track of the originating ifindex for each RR where that makes
  * sense, so that we can qualify A and AAAA RRs referring to a local link with the right ifindex.
@@ -29,6 +29,7 @@ typedef enum DnsAnswerFlags {
 } DnsAnswerFlags;
 
 struct DnsAnswerItem {
+        unsigned n_ref;
         DnsResourceRecord *rr;
         DnsResourceRecord *rrsig; /* Optionally, also store RRSIG RR that successfully validates this item */
         int ifindex;
@@ -37,9 +38,7 @@ struct DnsAnswerItem {
 
 struct DnsAnswer {
         unsigned n_ref;
-        Set *set_items; /* Used by dns_answer_add() for optimization. */
-        size_t n_rrs, n_allocated;
-        DnsAnswerItem items[0];
+        OrderedSet *items;
 };
 
 DnsAnswer *dns_answer_new(size_t n);
@@ -76,7 +75,7 @@ int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKe
 int dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname);
 
 static inline size_t dns_answer_size(DnsAnswer *a) {
-        return a ? a->n_rrs : 0;
+        return a ? ordered_set_size(a->items) : 0;
 }
 
 static inline bool dns_answer_isempty(DnsAnswer *a) {
@@ -91,50 +90,40 @@ uint32_t dns_answer_min_ttl(DnsAnswer *a);
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsAnswer*, dns_answer_unref);
 
-#define _DNS_ANSWER_FOREACH(q, kk, a)                                   \
-        for (size_t UNIQ_T(i, q) = ({                                   \
-                        (kk) = dns_answer_isempty(a) ? NULL : (a)->items[0].rr; \
-                        0;                                              \
-                });                                                     \
-             UNIQ_T(i, q) < dns_answer_size(a);                         \
-             UNIQ_T(i, q)++,                                            \
-                     (kk) = UNIQ_T(i, q) < dns_answer_size(a) ? (a)->items[UNIQ_T(i, q)].rr : NULL)
-
-#define DNS_ANSWER_FOREACH(kk, a) _DNS_ANSWER_FOREACH(UNIQ, kk, a)
-
-#define _DNS_ANSWER_FOREACH_IFINDEX(q, kk, ifi, a)                      \
-        for (size_t UNIQ_T(i, q) = ({                                   \
-                                (kk) = dns_answer_isempty(a) ? NULL : (a)->items[0].rr; \
-                                (ifi) = dns_answer_isempty(a) ? 0 : (a)->items[0].ifindex; \
-                                0;                                      \
-                        });                                             \
-             UNIQ_T(i, q) < dns_answer_size(a);                         \
-             UNIQ_T(i, q)++,                                            \
-                     (kk) = UNIQ_T(i, q) < dns_answer_size(a) ? (a)->items[UNIQ_T(i, q)].rr : NULL, \
-                     (ifi) = UNIQ_T(i, q) < dns_answer_size(a) ? (a)->items[UNIQ_T(i, q)].ifindex : 0)
-
-#define DNS_ANSWER_FOREACH_IFINDEX(kk, ifindex, a) _DNS_ANSWER_FOREACH_IFINDEX(UNIQ, kk, ifindex, a)
-
-#define _DNS_ANSWER_FOREACH_FLAGS(q, kk, fl, a)                         \
-        for (size_t UNIQ_T(i, q) = ({                                   \
-                                (kk) = dns_answer_isempty(a) ? NULL : (a)->items[0].rr; \
-                                (fl) = dns_answer_isempty(a) ? 0 : (a)->items[0].flags; \
-                                0;                                      \
-                        });                                             \
-             UNIQ_T(i, q) < dns_answer_size(a);                         \
-             UNIQ_T(i, q)++,                                            \
-                     (kk) = UNIQ_T(i, q) < dns_answer_size(a) ? (a)->items[UNIQ_T(i, q)].rr : NULL, \
-                     (fl) = UNIQ_T(i, q) < dns_answer_size(a) ? (a)->items[UNIQ_T(i, q)].flags : 0)
-
-#define DNS_ANSWER_FOREACH_FLAGS(kk, flags, a) _DNS_ANSWER_FOREACH_FLAGS(UNIQ, kk, flags, a)
-
-#define _DNS_ANSWER_FOREACH_ITEM(q, item, a)                            \
-        for (size_t UNIQ_T(i, q) = ({                                   \
-                                (item) = dns_answer_isempty(a) ? NULL : (a)->items; \
-                                0;                                      \
-                        });                                             \
-             UNIQ_T(i, q) < dns_answer_size(a);                         \
-             UNIQ_T(i, q)++,                                            \
-                     (item) = (UNIQ_T(i, q) < dns_answer_size(a)) ? (a)->items + UNIQ_T(i, q) : NULL)
-
-#define DNS_ANSWER_FOREACH_ITEM(item, a) _DNS_ANSWER_FOREACH_ITEM(UNIQ, item, a)
+typedef struct DnsAnswerIterator {
+        Iterator iterator;
+        DnsAnswer *answer;
+        DnsAnswerItem *item;
+} DnsAnswerIterator;
+
+#define _DNS_ANSWER_FOREACH(kk, a, i)                                   \
+        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
+             i.answer &&                                                \
+             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
+             (kk = i.item->rr, true); )
+
+#define DNS_ANSWER_FOREACH(rr, a) _DNS_ANSWER_FOREACH(rr, a, UNIQ_T(i, UNIQ))
+
+#define _DNS_ANSWER_FOREACH_IFINDEX(kk, ifi, a, i)                      \
+        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
+             i.answer &&                                                \
+             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
+             (kk = i.item->rr, ifi = i.item->ifindex, true); )
+
+#define DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a) _DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a, UNIQ_T(i, UNIQ))
+
+#define _DNS_ANSWER_FOREACH_FLAGS(kk, fl, a, i)                         \
+        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
+             i.answer &&                                                \
+             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
+             (kk = i.item->rr, fl = i.item->flags, true); )
+
+#define DNS_ANSWER_FOREACH_FLAGS(rr, flags, a) _DNS_ANSWER_FOREACH_FLAGS(rr, flags, a, UNIQ_T(i, UNIQ))
+
+#define _DNS_ANSWER_FOREACH_ITEM(item, a, i)                            \
+        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
+             i.answer &&                                                \
+             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
+             (item = i.item, true); )
+
+#define DNS_ANSWER_FOREACH_ITEM(item, a) _DNS_ANSWER_FOREACH_ITEM(item, a, UNIQ_T(i, UNIQ))