main: add json configuration path

If swampd is compiled to check for its configuration at run-time, it
will check one specific path.

Change-Id: I5c37ccbb2229db742c0f43b3d9ee0c368df19479
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/main.cpp b/main.cpp
index 4ff67c5..b00b7d3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -52,6 +52,9 @@
 /* The YAML converted Zone configuration. */
 extern std::map<int64_t, struct ZoneConfig> zoneDetailsConfig;
 
+/** the swampd daemon will check for the existence of this file. */
+constexpr auto jsonConfigurationPath = "/usr/share/swampd/config.json";
+
 int main(int argc, char* argv[])
 {
     int rc = 0;