Add z_getwitnesscachestats RPC to get various stats about the witness cache

src/wallet/rpcwallet.cpp

@@ -3636,6 +3636,43 @@ UniValue z_listsentbyaddress(const UniValue& params, bool fHelp,const CPubKey&)
     return ret;
 }
 
+UniValue z_getwitnesscachestats(const UniValue& params, bool fHelp, const CPubKey& mypk)
+{
+    if (!EnsureWalletIsAvailable(fHelp))
+        return NullUniValue;
+
+    if (fHelp || params.size() < 1 || params.size() > 2)
+        throw runtime_error(
+            "z_getwitnesscachestats\n"
+            "\nReturns statistics about the witness cache for zaddrs\n"
+            "\nResult:\n"
+            "\njson\n"
+            "\nExamples:\n"
+            + HelpExampleCli("z_getwitnesscachestats", "456")
+            + HelpExampleRpc("z_getwitnesscachestats", "456")
+         );
+
+    LOCK2(cs_main, pwalletMain->cs_wallet);
+    uint32_t nMinDepth = 1;
+    uint64_t total_witnesses = 0;
+    uint64_t total_zutxos = 0;
+    for (auto& wtx : pwalletMain->mapWallet) {
+        if (wtx.second.GetDepthInMainChain() >= nMinDepth) {
+            total_zutxos += wtx.second.mapSaplingNoteData.size();
+            for (mapSaplingNoteData_t::value_type& item : wtx.second.mapSaplingNoteData) {
+                auto* nd = &(item.second);
+                total_witnesses += nd->witnesses.size();
+            }
+        }
+    }
+    UniValue ret(UniValue::VOBJ);
+    ret.pushKV("total_witnesses", total_witnesses);
+    ret.pushKV("total_zutxos", total_zutxos);
+    ret.pushKV("witnesses_cache_size", pwalletMain->nWitnessCacheSize);
+    ret.pushKV("max_witnesses_cache_size", (int) WITNESS_CACHE_SIZE);
+    return ret;
+}
+
 UniValue z_getstats(const UniValue& params, bool fHelp, const CPubKey& mypk)
 {
     if (!EnsureWalletIsAvailable(fHelp))
@@ -8710,6 +8747,7 @@ static const CRPCCommand commands[] =
     { "wallet",             "z_getbalance",             &z_getbalance,             false },
     { "wallet",             "z_getbalances",            &z_getbalances,            false },
     { "wallet",             "z_getstats",               &z_getstats,               true  },
+    { "wallet",             "z_getwitnesscachestats",   &z_getwitnesscachestats,   true  },
     { "wallet",             "z_anonsettxdelta",         &z_anonsettxdelta,         true  },
     { "wallet",             "z_anonsetblockdelta",      &z_anonsetblockdelta,      true  },
     { "wallet",             "z_gettotalbalance",        &z_gettotalbalance,        false },