1 files changed, 17 insertions, 2 deletions

diff --git a/src/btfrv.h b/src/btfrv.h
index 9cd7476..1e85cb0 100644
--- a/src/btfrv.h
+++ b/src/btfrv.h
@@ -57,10 +57,25 @@ RvSocket RvServiceRegister(const char* relay_host, unsigned short port,
 bool RvServiceWaitPaired(RvSocket s, int nTimeoutSecs = 0);
 
 // ---- client side (the node dialing a .btf address) ----
+// Where a failed RvClientConnect stopped. RV_INVALID alone collapses three
+// different situations -- relay unreachable, relay reachable but nobody
+// registered, connection died mid-pairing -- and they point at different
+// components. The caller can only report the right one if this side says
+// which it saw.
+enum RvClientFail
+{
+    RVC_FAIL_NONE = 0,
+    RVC_FAIL_DIAL,    // TCP connect to the relay itself failed
+    RVC_FAIL_REFUSED, // relay answered 0x00: no service registered under this pubkey
+    RVC_FAIL_PAIR,    // relay connection died before pairing completed
+};
+
 // Connect through the relay to the service registered under `target_pubkey`.
-// Returns the paired socket, or RV_INVALID on error.
+// Returns the paired socket, or RV_INVALID on error -- with `pFail`, if
+// given, naming the stage that failed.
 RvSocket RvClientConnect(const char* relay_host, unsigned short port,
-                         const unsigned char target_pubkey[32]);
+                         const unsigned char target_pubkey[32],
+                         RvClientFail* pFail = 0);
 
 // Blocking read/write of exactly n bytes over a rendezvous socket. Return false
 // on error/EOF.