Conn: Add InitPostScript() and conn_id_ctx singleton

src/Conn.cc

@@ -6,6 +6,7 @@
 #include <cctype>
 
 #include "zeek/Desc.h"
+#include "zeek/ID.h"
 #include "zeek/NetVar.h"
 #include "zeek/Reporter.h"
 #include "zeek/RunState.h"
@@ -22,6 +23,12 @@ namespace zeek {
 
 uint64_t Connection::total_connections = 0;
 uint64_t Connection::current_connections = 0;
+zeek::RecordValPtr Connection::conn_id_ctx_singleton;
+
+void Connection::InitPostScript() {
+    if ( id::conn_id_ctx->NumFields() == 0 )
+        conn_id_ctx_singleton = zeek::make_intrusive<zeek::RecordVal>(id::conn_id_ctx);
+}
 
 Connection::Connection(zeek::IPBasedConnKeyPtr k, double t, uint32_t flow, const Packet* pkt)
     : Session(t, connection_timeout, connection_status_update, detail::connection_status_update_interval),

src/Conn.h

@@ -209,6 +209,9 @@ public:
     // Returns true once Done() is called.
     bool IsFinished() { return finished; }
 
+    // Runs after all scripts have been parsed.
+    static void InitPostScript();
+
 private:
     // Common initialization for the constructors. This can move back into the
     // (sole) constructor when we remove the deprecated one in 8.1.
@@ -244,6 +247,11 @@ private:
     // Count number of connections.
     static uint64_t total_connections;
     static uint64_t current_connections;
+
+    // When the conn_id_ctx record type has no fields,
+    // this holds a singleton record value for it that
+    // is shared among all conn_id record values.
+    static RecordValPtr conn_id_ctx_singleton;
 };
 
 // The following is used by script optimization.

src/zeek-setup.cc

@@ -25,6 +25,7 @@
 
 #include <binpac.h>
 
+#include "zeek/Conn.h"
 #include "zeek/DNS_Mgr.h"
 #include "zeek/Debug.h"
 #include "zeek/Desc.h"
@@ -842,6 +843,7 @@ SetupResult setup(int argc, char** argv, Options* zopts) {
             exit(1);
 
         RecordType::InitPostScript();
+        Connection::InitPostScript();
 
         conn_key_mgr->InitPostScript();
         telemetry_mgr->InitPostScript();