filters: remove ndb_filter_group from public API

We can just use a list of filters instead when subscribing

src/nostrdb.c

@@ -35,6 +35,8 @@ static const int THREAD_QUEUE_BATCH = 4096;
 
 // maximum number of active subscriptions
 #define MAX_SUBSCRIPTIONS 32
+#define MAX_SCAN_CURSORS 12
+#define MAX_FILTERS    16
 
 // the maximum size of inbox queues
 static const int DEFAULT_QUEUE_SIZE = 1000000;
@@ -175,6 +177,11 @@ struct ndb_ingester {
 	ndb_ingest_filter_fn filter;
 };
 
+struct ndb_filter_group {
+	struct ndb_filter *filters[MAX_FILTERS];
+	int num_filters;
+};
+
 struct ndb_subscription {
 	uint64_t subid;
 	struct ndb_filter_group group;
@@ -213,7 +220,7 @@ struct ndb_scan_cursor {
 
 // same idea as DBScan in strfry
 struct ndb_dbscan {
-	struct ndb_scan_cursor cursors[12];
+	struct ndb_scan_cursor cursors[MAX_SCAN_CURSORS];
 	int num_cursors;
 };
 
@@ -916,15 +923,15 @@ void ndb_filter_end_field(struct ndb_filter *filter)
 
 }
 
-void ndb_filter_group_init(struct ndb_filter_group *group)
+static void ndb_filter_group_init(struct ndb_filter_group *group)
 {
 	group->num_filters = 0;
 }
 
-int ndb_filter_group_add(struct ndb_filter_group *group,
+static int ndb_filter_group_add(struct ndb_filter_group *group,
 				struct ndb_filter *filter)
 {
-	if (group->num_filters + 1 > NDB_MAX_FILTERS)
+	if (group->num_filters + 1 > MAX_FILTERS)
 		return 0;
 
 	group->filters[group->num_filters++] = filter;
@@ -5018,7 +5025,7 @@ int ndb_wait_for_notes(struct ndb *ndb, uint64_t subid, uint64_t *note_ids,
 	return prot_queue_pop_all(&sub->inbox, note_ids, note_id_capacity);
 }
 
-uint64_t ndb_subscribe(struct ndb *ndb, struct ndb_filter_group *group)
+uint64_t ndb_subscribe(struct ndb *ndb, struct ndb_filter *filters, int num_filters)
 {
 	static uint64_t subids = 0;
 	struct ndb_subscription *sub;
@@ -5037,8 +5044,12 @@ uint64_t ndb_subscribe(struct ndb *ndb, struct ndb_filter_group *group)
 	subid = ++subids;
 	sub->subid = subid;
 
-	memcpy(&sub->group, group, sizeof(*group));
-
+	ndb_filter_group_init(&sub->group);
+	for (index = 0; index < num_filters; index++) {
+		if (!ndb_filter_group_add(&sub->group, &filters[index]))
+			return 0;
+	}
+
 	// 500k ought to be enough for anyone
 	buflen = sizeof(uint64_t) * 65536;
 	buf = malloc(buflen);

src/nostrdb.h

@@ -4,9 +4,6 @@
 #include <inttypes.h>
 #include "cursor.h"
 
-// how many filters are allowed in a filter group
-#define NDB_MAX_FILTERS    16
-
 // maximum number of filters allowed in a filter group
 #define NDB_PACKED_STR     0x1
 #define NDB_PACKED_ID      0x2
@@ -30,7 +27,6 @@ struct ndb_blocks;
 struct ndb_block;
 struct ndb_note;
 struct ndb_tag;
-struct ndb_filter_group;
 struct ndb_tags;
 struct ndb_lmdb;
 union ndb_packed_str;
@@ -241,11 +237,6 @@ struct ndb_filter {
 	struct ndb_filter_elements *elements[NDB_NUM_FILTERS];
 };
 
-struct ndb_filter_group {
-	struct ndb_filter *filters[NDB_MAX_FILTERS];
-	int num_filters;
-};
-
 struct ndb_config {
 	int flags;
 	int ingester_threads;
@@ -470,12 +461,10 @@ int ndb_filter_start_generic_field(struct ndb_filter *, char tag);
 int ndb_filter_matches(struct ndb_filter *, struct ndb_note *);
 void ndb_filter_reset(struct ndb_filter *);
 void ndb_filter_end_field(struct ndb_filter *);
-void ndb_filter_group_init(struct ndb_filter_group *group);
-int ndb_filter_group_add(struct ndb_filter_group *group, struct ndb_filter *f);
 void ndb_filter_destroy(struct ndb_filter *);
 
 // SUBSCRIPTIONS
-uint64_t ndb_subscribe(struct ndb *, struct ndb_filter_group *);
+uint64_t ndb_subscribe(struct ndb *, struct ndb_filter *, int num_filters);
 int ndb_wait_for_notes(struct ndb *, uint64_t subid, uint64_t *note_ids,
 		       int note_id_capacity);
 int ndb_unsubscribe(int subid);

test.c

@@ -220,15 +220,13 @@ static void test_reaction_counter()
 	struct ndb_config config;
 	ndb_default_config(&config);
 	static const int num_reactions = 3;
-	struct ndb_filter_group group;
 	uint64_t note_ids[num_reactions], subid;
 
 	assert(ndb_init(&ndb, test_dir, &config));
 
 	read_file("testdata/reactions.json", (unsigned char*)json, alloc_size, &written);
 
-	group.num_filters = 0;
-	assert((subid = ndb_subscribe(ndb, &group)));
+	assert((subid = ndb_subscribe(ndb, NULL, 0)));
 
 	assert(ndb_process_client_events(ndb, json, written));
 
@@ -299,7 +297,6 @@ static void test_profile_updates()
 	size_t len;
 	struct ndb *ndb;
 	struct ndb_config config;
-	struct ndb_filter_group group;
 	struct ndb_txn txn;
 	uint64_t key, subid;
 	uint64_t note_ids[num_notes];
@@ -310,8 +307,7 @@ static void test_profile_updates()
 	ndb_default_config(&config);
 	assert(ndb_init(&ndb, test_dir, &config));
 
-	ndb_filter_group_init(&group);
-	subid = ndb_subscribe(ndb, &group);
+	subid = ndb_subscribe(ndb, NULL, 0);
 
 	ndb_debug("testing profile updates\n");
 	read_file("testdata/profile-updates.json", (unsigned char*)json, alloc_size, &written);
@@ -1234,7 +1230,6 @@ static void test_subscriptions()
 	struct ndb_filter filter, *f = &filter;
 	uint64_t subid;
 	uint64_t note_id = 0;
-	struct ndb_filter_group group;
 	struct ndb_txn txn;
 	struct ndb_note *note;
 	ndb_default_config(&config);
@@ -1248,10 +1243,7 @@ static void test_subscriptions()
 	assert(ndb_filter_add_int_element(f, 1337));
 	ndb_filter_end_field(f);
 
-	ndb_filter_group_init(&group);
-	ndb_filter_group_add(&group, f);
-
-	assert((subid = ndb_subscribe(ndb, &group)));
+	assert((subid = ndb_subscribe(ndb, NULL, 0)));
 
 	assert(ndb_process_event(ndb, ev, strlen(ev)));