Delay remote ACK delivery independently in the BLE fixture

lib/ble/tests/test_ble_transport.c

@@ -9,7 +9,7 @@
 #define CHECK(v) do { if (!(v)) { fprintf(stderr, "FAIL line=%d: %s\n", __LINE__, #v); exit(1); } } while (0)
 struct fake_link {
     ble_link_id id, other; struct ble_backend* peer; uint8_t data[512]; size_t len; int pending;
-    enum ble_wire_channel channel; uint64_t ack_at; uint16_t ack_id, ack_delivered;
+    enum ble_wire_channel channel; uint64_t ack_at; uint16_t ack_id, ack_delivered; int ack_held;
 };
 struct ble_backend { struct ble_transport* owner; struct UASYNC* ua; void* task; int index, started; struct fake_link links[16]; };
 static struct ble_backend* backends[3];
@@ -63,13 +63,18 @@ static void run(void* arg) {
     if (!b->started) { b->started = 1; ble_backend_status(b->owner, 1, "fake ready"); }
     for (int i = 0; i < 16; i++) {
         struct fake_link* f = &b->links[i]; if (!f->id) continue;
+        if (!hold_ack && f->ack_held) {
+            uint8_t ack[2] = {f->ack_id >> 8, f->ack_id}; f->ack_held = 0; f->ack_delivered = f->ack_id;
+            if (f->peer && slot(f->peer, f->other)) ble_backend_received(f->peer->owner, f->other, BLE_WIRE_ACK, ack, 2);
+        }
         if (!f->len) { f->len = 1; ble_backend_opened(b->owner, f->id, mtu); }
-        if (!f->pending || hold || (hold_ack && f->channel == BLE_WIRE_ACK)) continue;
+        if (!f->pending || hold) continue;
         ble_link_id id = f->id, other = f->other;
         struct ble_backend* peer = f->peer;
         uint8_t data[512]; size_t len = f->len; memcpy(data, f->data, len); f->pending = 0;
         int dropped = f->channel != BLE_WIRE_ACK && data[f->channel == BLE_WIRE_DATA ? 2 : 0] == 3 && drop && --drop == 0;
-        if (!dropped && peer && slot(peer, other)) {
+        if (hold_ack && f->channel == BLE_WIRE_ACK) f->ack_held = 1;
+        else if (!dropped && peer && slot(peer, other)) {
             if (f->channel == BLE_WIRE_ACK) f->ack_delivered = f->ack_id;
             ble_backend_received(peer->owner, other, f->channel, data, len);
         }