Add InterfaceInfo formatter

llarp/CMakeLists.txt

@@ -33,6 +33,7 @@ add_library(lokinet-platform
   # for networking
   ev/ev.cpp
   ev/libuv.cpp
+  net/interface_info.cpp
   net/ip.cpp
   net/ip_address.cpp
   net/ip_packet.cpp

llarp/net/interface_info.cpp

@@ -0,0 +1,15 @@
+#include "interface_info.hpp"
+
+namespace llarp::net
+{
+  std::string
+  InterfaceInfo::ToString() const
+  {
+    return fmt::format(
+        "{}[i={}; addrs={}; gw={}]",
+        name,
+        index,
+        fmt::join(addrs, ","),
+        gateway ? fmt::format("{}", *gateway) : "none");
+  }
+}  // namespace llarp::net

llarp/net/interface_info.hpp

@@ -1,7 +1,9 @@
 #pragma once
 
+#include <optional>
 #include <string>
 #include <vector>
+#include <llarp/util/formattable.hpp>
 #include "ip_range.hpp"
 
 namespace llarp::net
@@ -17,5 +19,11 @@ namespace llarp::net
     std::vector<IPRange> addrs;
     /// a gateway we can use if it exists
     std::optional<ipaddr_t> gateway;
+
+    std::string
+    ToString() const;
   };
 }  // namespace llarp::net
+
+template <>
+inline constexpr bool llarp::IsToStringFormattable<llarp::net::InterfaceInfo> = true;