v1 traps with empty varbinds can't be parsed

[movaps]

I've noticed that some agents (e.g. HP 2650) send their variable-less traps (e.g. authenticationFailure) with the message stopping abruptly after varbinds SEQUENCE marker, causing snmpjs to discard the trap with an error. While these traps aren't entirely kosher, every NMS I've tried handles them gracefully and there's little point in discarding the trap when all the actual information contained therein has been successfully parsed.

Here's a small patch that fixes the issue;

diff --git lib/snmp.jison lib/snmp.jison
index e9c6a7a..7958d3c 100644
--- lib/snmp.jison
+++ lib/snmp.jison
@@ -134,8 +134,7 @@ pdu
                $$.error_status = $3;
                $$.error_index = $4;
        }}
-       | obsolete_trap_pdu_tag oid ip_address integer integer time_ticks
-         varbind_list {{
+       | obsolete_trap_pdu_tag oid ip_address integer integer time_ticks varbind_list_v1 {{
                $$ = yy.pdu.createPDU({ op: $1, varbinds: $7 });
                $$.enterprise = $2;
                $$.agent_addr = $3;
@@ -160,6 +159,15 @@ obsolete_trap_pdu_tag
        : 'CONTEXT_CONSTRUCTED_4' {{ $$ = yy.pdu.Trap; }}
        ;

+
+varbind_list_v1
+       : 'SEQUENCE' varbinds {{
+               $$ = $2;
+       }}
+       | 'SEQUENCE'
+       |
+       ;
+
 varbind_list
        : 'SEQUENCE' varbinds {{
                $$ = $2;

[ghost]

Thanks! Fixed in 0.1.7.