Un-mangle Destination in case we need to somehow pass one to DestroyLocalDestination,RequestLeaseSet, etc

Makefile

@@ -147,6 +147,6 @@ doxygen:
 ##TODO: delete this before a PR
 testc: api api_client
 #	g++ -Ii18n -c test.c -o test.o
-	gcc -Ii18n -c _test.c -o test.o
+	gcc -llibi2pd.so -c _test.c -o test.o
 #	gcc -Ii18n -I/usr/include/c++/10 -I/usr/include/x86_64-linux-gnu/c++/10 -llibi2pd.a -c test.c -o test.o
 	g++ test.o libi2pd.so libi2pdclient.so -o test.main

libi2pd/Identity.h

@@ -20,6 +20,10 @@
 #include "Signature.h"
 #include "CryptoKey.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 namespace i2p
 {
 namespace data
@@ -244,4 +248,8 @@ namespace data
 }
 }
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif