prefetch and expose it

include/llarp.h

@@ -103,6 +103,10 @@ extern "C"
   bool
   main_router_mapAddress(struct llarp_main *ptr, const llarp::service::Address &addr, uint32_t ip);
 
+  /// info of possible path usage
+  bool
+  main_router_prefetch(struct llarp_main *ptr, const llarp::service::Address &addr);
+
 }
 #endif
 #endif

include/llarp/service/context.hpp

@@ -27,6 +27,10 @@ namespace llarp
       llarp_tun_io *
       getRange();
 
+      /// hint at possible path usage and trigger building early
+      bool
+      Prefetch(const llarp::service::Address &addr);
+
       /// punch a hole open for DNS to add mappings
       bool
       MapAddress(const llarp::service::Address &addr, uint32_t ip);

llarp/context.cpp

@@ -451,6 +451,13 @@ main_router_mapAddress(struct llarp_main *ptr, const llarp::service::Address &ad
   return endpoint->MapAddress(addr, ip);
 }
 
+bool
+main_router_prefetch(struct llarp_main *ptr, const llarp::service::Address &addr)
+{
+  auto *endpoint = &ptr->ctx->router->hiddenServiceContext;
+  return endpoint->Prefetch(addr);
+}
+
 llarp_tun_io *
 main_router_getRange(struct llarp_main *ptr)
 {

llarp/service/context.cpp

@@ -1,5 +1,6 @@
 #include <llarp/handlers/tun.hpp>
 #include <llarp/service/context.hpp>
+#include <llarp/service/endpoint.hpp>
 
 namespace llarp
 {
@@ -57,6 +58,19 @@ namespace llarp
       return &tunEndpoint->tunif;
     }
 
+    bool
+    Context::Prefetch(const llarp::service::Address &addr)
+    {
+      llarp::handlers::TunEndpoint *tunEndpoint = this->getFirstTun();
+      if (!tunEndpoint)
+      {
+        llarp::LogError("No tunnel endpoint found");
+        return false;
+      }
+      //HiddenServiceAddresslookup *lookup = new HiddenServiceEndpoint(tunEndpoint, callback, addr, tunEndpoint->GenTXID());
+      return tunEndpoint->EnsurePathToService(addr, [](Address addr, void* ctx) {}, 10000);
+    }
+
     bool
     Context::MapAddress(const llarp::service::Address &addr, uint32_t ip)
     {