Have tap listeners specify whether the "packet" routine requires

	a protocol tree;

	the column values.

This includes stats-tree listeners.

Have the routines to build the packet list, and to retap packets, honor
those requirements.  This means that cf_retap_packets() no longer needs
an argument to specify whether to construct the column values or not, so
get rid of that argument.

This also means that there's no need for a tap to have a fake filter
to ensure that the protocol tree will be built, so don't set up a fake
"frame" filter.

While we're at it, clean up some cases where "no filter" was represented
as a null string rather than a null pointer.

Have a routine to return an indication of the number of tap listeners
with filters; use that rather than the global num_tap_filters.

Clean up some indentation and some gboolean vs. gint items.

svn path=/trunk/; revision=28645

15 files changed, 136 insertions, 81 deletions

diff --git a/epan/dissectors/packet-http.c b/epan/dissectors/packet-http.c
index c05230584c..f62b69b3b0 100644
--- a/epan/dissectors/packet-http.c
+++ b/epan/dissectors/packet-http.c
@@ -2569,9 +2569,9 @@ proto_reg_handoff_http(void)
 	ntlmssp_handle = find_dissector("ntlmssp");
 	gssapi_handle = find_dissector("gssapi");
 
-	stats_tree_register("http","http","HTTP/Packet Counter", http_stats_tree_packet, http_stats_tree_init, NULL );
-	stats_tree_register("http","http_req","HTTP/Requests", http_req_stats_tree_packet, http_req_stats_tree_init, NULL );
-	stats_tree_register("http","http_srv","HTTP/Load Distribution",http_reqs_stats_tree_packet,http_reqs_stats_tree_init, NULL );
+	stats_tree_register("http","http","HTTP/Packet Counter", 0, http_stats_tree_packet, http_stats_tree_init, NULL );
+	stats_tree_register("http","http_req","HTTP/Requests", 0, http_req_stats_tree_packet, http_req_stats_tree_init, NULL );
+	stats_tree_register("http","http_srv","HTTP/Load Distribution",0,http_reqs_stats_tree_packet,http_reqs_stats_tree_init, NULL );
 
 }
 
diff --git a/epan/dissectors/packet-isup.c b/epan/dissectors/packet-isup.c
index 83ca4496ec..1ad7904312 100644
--- a/epan/dissectors/packet-isup.c
+++ b/epan/dissectors/packet-isup.c
@@ -8258,7 +8258,7 @@ proto_register_isup(void)
 
 	/* Register the stats_tree */
 	stats_tree_register_with_group("isup", "isup_msg", "ISUP Messages",
-			    msg_stats_tree_packet, msg_stats_tree_init,
+		0, msg_stats_tree_packet, msg_stats_tree_init,
                 NULL, REGISTER_STAT_GROUP_TELEPHONY);
 }
 
diff --git a/epan/dissectors/packet-smb-sidsnooping.c b/epan/dissectors/packet-smb-sidsnooping.c
index 59e7854c72..80cb7f5670 100644
--- a/epan/dissectors/packet-smb-sidsnooping.c
+++ b/epan/dissectors/packet-smb-sidsnooping.c
@@ -404,7 +404,10 @@ sid_name_snooping=0;
 	}
 
 
-	error_string=register_tap_listener("dcerpc", &lsa_policy_information_tap_installed, "lsa.policy_information and ( lsa.info.level or lsa.domain or nt.domain_sid )", NULL, lsa_policy_information, NULL);
+	error_string=register_tap_listener("dcerpc",
+	    &lsa_policy_information_tap_installed,
+	    "lsa.policy_information and ( lsa.info.level or lsa.domain or nt.domain_sid )",
+	    TL_REQUIRES_PROTO_TREE, NULL, lsa_policy_information, NULL);
 	if(error_string){
 		/* error, we failed to attach to the tap. clean up */
 
@@ -415,7 +418,10 @@ sid_name_snooping=0;
 	}
 	lsa_policy_information_tap_installed=TRUE;
 
-	error_string=register_tap_listener("dcerpc", &samr_query_dispinfo_tap_installed, "samr and samr.opnum==40 and ( samr.handle or samr.rid or samr.acct_name or samr.level )", NULL, samr_query_dispinfo, NULL);
+	error_string=register_tap_listener("dcerpc",
+	    &samr_query_dispinfo_tap_installed,
+	    "samr and samr.opnum==40 and ( samr.handle or samr.rid or samr.acct_name or samr.level )",
+	    TL_REQUIRES_PROTO_TREE, NULL, samr_query_dispinfo, NULL);
 	if(error_string){
 		/* error, we failed to attach to the tap. clean up */
 
diff --git a/epan/dissectors/packet-smb.c b/epan/dissectors/packet-smb.c
index 46aa05a012..1c84372628 100644
--- a/epan/dissectors/packet-smb.c
+++ b/epan/dissectors/packet-smb.c
@@ -6712,7 +6712,8 @@ dissect_session_setup_andx_request(tvbuff_t *tvb, packet_info *pinfo, proto_tree
 		 * security blob has been fully dissected and before
 		 * we exit from this dissector.
 		 */
-		error_string=register_tap_listener("ntlmssp", NULL, NULL, NULL, NULL, NULL);
+		error_string=register_tap_listener("ntlmssp", NULL, NULL,
+		    0, NULL, NULL, NULL);
 		if(!error_string){
 			ntlmssp_tap_id=find_tap_id("ntlmssp");
 		}
diff --git a/epan/dissectors/packet-smb2.c b/epan/dissectors/packet-smb2.c
index 9f66c9c905..b07de7f35c 100644
--- a/epan/dissectors/packet-smb2.c
+++ b/epan/dissectors/packet-smb2.c
@@ -1988,7 +1988,8 @@ dissect_smb2_session_setup_request(tvbuff_t *tvb, packet_info *pinfo, proto_tree
 		 * security blob has been fully dissected and before
 		 * we exit from this dissector.
 		 */
-		error_string=register_tap_listener("ntlmssp", NULL, NULL, NULL, NULL, NULL);
+		error_string=register_tap_listener("ntlmssp", NULL, NULL,
+		    0, NULL, NULL, NULL);
 		if(!error_string){
 			ntlmssp_tap_id=find_tap_id("ntlmssp");
 		}
diff --git a/epan/dissectors/packet-smpp.c b/epan/dissectors/packet-smpp.c
index a21608ac98..cdf5601bd5 100644
--- a/epan/dissectors/packet-smpp.c
+++ b/epan/dissectors/packet-smpp.c
@@ -3544,7 +3544,7 @@ proto_reg_handoff_smpp(void)
     DISSECTOR_ASSERT(gsm_sms_handle);
 
     /* Tapping setup */
-    stats_tree_register_with_group("smpp","smpp_commands", st_str_smpp,
+    stats_tree_register_with_group("smpp","smpp_commands", st_str_smpp, 0,
                                    smpp_stats_tree_per_packet, smpp_stats_tree_init, 
                                    NULL, REGISTER_STAT_GROUP_TELEPHONY);
 }
diff --git a/epan/dissectors/packet-ucp.c b/epan/dissectors/packet-ucp.c
index 0c1c966ad7..1e2aadaf19 100644
--- a/epan/dissectors/packet-ucp.c
+++ b/epan/dissectors/packet-ucp.c
@@ -2757,7 +2757,7 @@ proto_reg_handoff_ucp(void)
     dissector_add_handle("tcp.port", ucp_handle);
 
     /* Tapping setup */
-    stats_tree_register_with_group("ucp", "ucp_messages", st_str_ucp,
+    stats_tree_register_with_group("ucp", "ucp_messages", st_str_ucp, 0,
 			ucp_stats_tree_per_packet, ucp_stats_tree_init,
 			NULL, REGISTER_STAT_GROUP_TELEPHONY);
 }
diff --git a/epan/libwireshark.def b/epan/libwireshark.def
index 239ca9fa28..c0c3de6ec4 100644
--- a/epan/libwireshark.def
+++ b/epan/libwireshark.def
@@ -539,6 +539,7 @@ h245_set_h223_set_mc_handle
 h248_param_ber_integer 
 h248_register_package 
 have_custom_cols
+have_filtering_tap_listeners
 have_tap_listeners
 heur_dissector_add
 heur_dissector_delete
@@ -596,7 +597,6 @@ nstime_sum
 nstime_to_msec
 nstime_to_sec
 nt_cmd_vals                     DATA
-num_tap_filters                 DATA
 num_tree_types                  DATA
 offset_from_real_beginning
 oid_add
@@ -1033,6 +1033,7 @@ uat_new
 uat_remove_record_idx
 uat_save
 uat_swap
+union_of_tap_listener_flags
 UnregRejectReason_vals          DATA
 UnregRequestReason_vals         DATA
 uri_str_to_bytes
diff --git a/epan/stats_tree.c b/epan/stats_tree.c
index 7fbf32362b..554c50eb2a 100644
--- a/epan/stats_tree.c
+++ b/epan/stats_tree.c
@@ -260,6 +260,7 @@ stats_tree_reinit(void *p)
 /* register a new stats_tree */
 extern void
 stats_tree_register_with_group(const char *tapname, const char *abbr, const char *name,
+		    guint flags,
 		    stat_tree_packet_cb packet, stat_tree_init_cb init,
 		    stat_tree_cleanup_cb cleanup, register_stat_group_t stat_group)
 {
@@ -272,11 +273,13 @@ stats_tree_register_with_group(const char *tapname, const char *abbr, const char
 	cfg->tapname = g_strdup(tapname);
 	cfg->abbr = g_strdup(abbr);
 	cfg->name = name ? g_strdup(name) : g_strdup(abbr);
-    cfg->stat_group = stat_group;
+	cfg->stat_group = stat_group;
 	
 	cfg->packet = packet;
 	cfg->init = init;
 	cfg->cleanup = cleanup;
+
+	cfg->flags = flags;
 	
 	/* these have to be filled in by implementations */
 	cfg->setup_node_pr = NULL;
@@ -297,10 +300,12 @@ stats_tree_register_with_group(const char *tapname, const char *abbr, const char
 /* register a new stats_tree with default group REGISTER_STAT_GROUP_UNSORTED */
 extern void
 stats_tree_register(const char *tapname, const char *abbr, const char *name,
+		    guint flags,
 		    stat_tree_packet_cb packet, stat_tree_init_cb init,
 		    stat_tree_cleanup_cb cleanup)
 {
-    stats_tree_register_with_group(tapname, abbr, name,
+	stats_tree_register_with_group(tapname, abbr, name,
+		    flags,
 		    packet, init,
 		    cleanup, REGISTER_STAT_GROUP_UNSORTED);
 }
diff --git a/epan/stats_tree.h b/epan/stats_tree.h
index 66a0c556cd..fcbc9025dd 100644
--- a/epan/stats_tree.h
+++ b/epan/stats_tree.h
@@ -53,6 +53,7 @@ typedef void  (*stat_tree_cleanup_cb)(stats_tree*);
 /* registers a new stats tree with default group REGISTER_STAT_GROUP_UNSORTED
  * abbr: protocol abbr
  * name: protocol display name
+ * flags: tap listener flags for per-packet callback
  * packet: per packet callback
  * init: tree initialization callback
  * cleanup: cleanup callback
@@ -60,6 +61,7 @@ typedef void  (*stat_tree_cleanup_cb)(stats_tree*);
 extern void stats_tree_register(const gchar *tapname,
 				const gchar *abbr, 
 				const gchar *name,
+				guint flags,
 				stat_tree_packet_cb packet,
 				stat_tree_init_cb init,
 				stat_tree_cleanup_cb cleanup);
@@ -67,6 +69,7 @@ extern void stats_tree_register(const gchar *tapname,
 /* registers a new stats tree 
  * abbr: protocol abbr
  * name: protocol display name
+ * flags: tap listener flags for per-packet callback
  * packet: per packet callback
  * init: tree initialization callback
  * cleanup: cleanup callback
@@ -75,10 +78,11 @@ extern void stats_tree_register(const gchar *tapname,
 extern void stats_tree_register_with_group(const gchar *tapname,
 				const gchar *abbr, 
 				const gchar *name,
+				guint flags,
 				stat_tree_packet_cb packet,
 				stat_tree_init_cb init,
 				stat_tree_cleanup_cb cleanup,
-                register_stat_group_t stat_group);
+				register_stat_group_t stat_group);
 
 extern int stats_tree_parent_id_by_name(stats_tree *st, const gchar *parent_name);
 
diff --git a/epan/stats_tree_priv.h b/epan/stats_tree_priv.h
index 7bfd9015bf..24e4f4df6f 100644
--- a/epan/stats_tree_priv.h
+++ b/epan/stats_tree_priv.h
@@ -110,7 +110,7 @@ struct _stats_tree_cfg {
 	gchar*			abbr;
 	gchar*			name;
 	gchar*			tapname;
-    register_stat_group_t stat_group;
+	register_stat_group_t	stat_group;
 	
 	gboolean in_use;
 
@@ -118,6 +118,9 @@ struct _stats_tree_cfg {
 	stat_tree_packet_cb packet;
 	stat_tree_init_cb init;
 	stat_tree_cleanup_cb cleanup;
+
+	/* tap listener flags for the per-packet callback */
+	guint flags;
 	
 	/*
 	 * node presentation callbacks
diff --git a/epan/tap.c b/epan/tap.c
index d53bdd0432..acab1fd5d3 100644
--- a/epan/tap.c
+++ b/epan/tap.c
@@ -42,7 +42,6 @@
 #include <epan/tap.h>
 
 static gboolean tapping_is_active=FALSE;
-int num_tap_filters=0;
 
 typedef struct _tap_dissector_t {
 	struct _tap_dissector_t *next;
@@ -70,7 +69,8 @@ static guint tap_packet_index;
 typedef struct _tap_listener_t {
 	struct _tap_listener_t *next;
 	int tap_id;
-	int needs_redraw;
+	gboolean needs_redraw;
+	guint flags;
 	dfilter_t *code;
 	void *tapdata;
 	tap_reset_cb reset;
@@ -247,7 +247,7 @@ tap_push_tapped_queue(epan_dissect_t *edt)
 		for(tl=(tap_listener_t *)tap_listener_queue;tl;tl=tl->next){
 			tp=&tap_packet_array[i];
 			if(tp->tap_id==tl->tap_id){
-				int passed=TRUE;
+				gboolean passed=TRUE;
 				if(tl->code){
 					passed=dfilter_apply_edt(tl->code, edt);
 				}
@@ -315,7 +315,7 @@ reset_tap_listeners(void)
 		if(tl->reset){
 			tl->reset(tl->tapdata);
 		}
-		tl->needs_redraw=1;
+		tl->needs_redraw=TRUE;
 	}
 
 }
@@ -339,7 +339,7 @@ draw_tap_listeners(gboolean draw_all)
 				tl->draw(tl->tapdata);
 			}
 		}
-		tl->needs_redraw=0;
+		tl->needs_redraw=FALSE;
 	}
 }
 
@@ -376,7 +376,8 @@ find_tap_id(const char *name)
  *           message.
  */
 GString *
-register_tap_listener(const char *tapname, void *tapdata, const char *fstring, tap_reset_cb reset, tap_packet_cb packet, tap_draw_cb draw)
+register_tap_listener(const char *tapname, void *tapdata, const char *fstring,
+    guint flags, tap_reset_cb reset, tap_packet_cb packet, tap_draw_cb draw)
 {
 	tap_listener_t *tl;
 	int tap_id;
@@ -391,7 +392,8 @@ register_tap_listener(const char *tapname, void *tapdata, const char *fstring, t
 
 	tl=g_malloc(sizeof(tap_listener_t));
 	tl->code=NULL;
-	tl->needs_redraw=1;
+	tl->needs_redraw=TRUE;
+	tl->flags=flags;
 	if(fstring){
 		if(!dfilter_compile(fstring, &tl->code)){
 			error_string = g_string_new("");
@@ -400,8 +402,6 @@ register_tap_listener(const char *tapname, void *tapdata, const char *fstring, t
 			    fstring, dfilter_error_msg);
 			g_free(tl);
 			return error_string;
-		} else {
-			num_tap_filters++;
 		}
 	}
 
@@ -444,10 +444,9 @@ set_tap_dfilter(void *tapdata, const char *fstring)
 	if(tl){
 		if(tl->code){
 			dfilter_free(tl->code);
-			num_tap_filters--;
 			tl->code=NULL;
 		}
-		tl->needs_redraw=1;
+		tl->needs_redraw=TRUE;
 		if(fstring){
 			if(!dfilter_compile(fstring, &tl->code)){
 				error_string = g_string_new("");
@@ -455,8 +454,6 @@ set_tap_dfilter(void *tapdata, const char *fstring)
 						 "Filter \"%s\" is invalid - %s",
 						 fstring, dfilter_error_msg);
 				return error_string;
-			} else {
-				num_tap_filters++;
 			}
 		}
 	}
@@ -492,7 +489,6 @@ remove_tap_listener(void *tapdata)
 	if(tl){
 		if(tl->code){
 			dfilter_free(tl->code);
-			num_tap_filters--;
 		}
 		g_free(tl);
 	}
@@ -502,11 +498,6 @@ remove_tap_listener(void *tapdata)
 
 /*
  * Return TRUE if we have tap listeners, FALSE otherwise.
- * Checking "num_tap_filters" isn't the right way to check whether we need
- * to do any dissection in order to run taps, as not all taps necessarily
- * have filters, and "num_tap_filters" is the number of tap filters, not
- * the number of tap listeners; it's only the right way to check whether
- * we need to build a protocol tree when doing dissection.
  */
 gboolean
 have_tap_listeners(void)
@@ -529,3 +520,35 @@ have_tap_listener(int tap_id)
 
 	return FALSE;
 }
+
+/*
+ * Return TRUE if we have any tap listeners with filters, FALSE otherwise.
+ */
+gboolean
+have_filtering_tap_listeners(void)
+{
+	tap_listener_t *tl;
+
+	for(tl=(tap_listener_t *)tap_listener_queue;tl;tl=tl->next){
+		if(tl->code)
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/*
+ * Get the union of all the flags for all the tap listeners; that gives
+ * an indication of whether the protocol tree, or the columns, are
+ * required by any taps.
+ */
+guint
+union_of_tap_listener_flags(void)
+{
+	tap_listener_t *tl;
+	guint flags = 0;
+
+	for(tl=(tap_listener_t *)tap_listener_queue;tl;tl=tl->next){
+		flags|=tl->flags;
+	}
+	return flags;
+}
diff --git a/epan/tap.h b/epan/tap.h
index 4f4855deff..9bc66949e4 100644
--- a/epan/tap.h
+++ b/epan/tap.h
@@ -27,15 +27,15 @@
 
 #include "epan/epan.h"
 
-/* With MSVC and a libwireshark.dll, we need a 
- * special declaration of num_tap_filters.
- */
-WS_VAR_IMPORT int num_tap_filters;
-
 typedef void (*tap_reset_cb)(void *tapdata);
-typedef int  (*tap_packet_cb)(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data);
+typedef gboolean (*tap_packet_cb)(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data);
 typedef void (*tap_draw_cb)(void *tapdata);
 
+/*
+ * Flags to indicate what a tap listener's packet routine requires.
+ */
+#define TL_REQUIRES_PROTO_TREE		0x00000001	/* full protocol tree */
+#define TL_REQUIRES_COLUMNS		0x00000002	/* columns */
 
 extern void tap_init(void);
 extern int register_tap(const char *name);
@@ -46,12 +46,14 @@ extern void tap_push_tapped_queue(epan_dissect_t *edt);
 extern void reset_tap_listeners(void);
 extern void draw_tap_listeners(gboolean draw_all);
 extern GString *register_tap_listener(const char *tapname, void *tapdata,
-    const char *fstring, tap_reset_cb tap_reset, tap_packet_cb tap_packet,
-    tap_draw_cb tap_draw);
+    const char *fstring, guint flags, tap_reset_cb tap_reset,
+    tap_packet_cb tap_packet, tap_draw_cb tap_draw);
 extern GString *set_tap_dfilter(void *tapdata, const char *fstring);
 extern void remove_tap_listener(void *tapdata);
 extern gboolean have_tap_listeners(void);
 extern gboolean have_tap_listener(int tap_id);
+extern gboolean have_filtering_tap_listeners(void);
+extern guint union_of_tap_listener_flags(void);
 extern const void *fetch_tapped_data(int tap_id, int idx);
 
 #endif
diff --git a/epan/wslua/wslua_field.c b/epan/wslua/wslua_field.c
index c95a07b698..84ba0a01a1 100644
--- a/epan/wslua/wslua_field.c
+++ b/epan/wslua/wslua_field.c
@@ -369,9 +369,10 @@ void lua_prime_all_fields(proto_tree* tree _U_) {
     if (fake_tap) {
         /* a boring tap :-) */
         GString* error = register_tap_listener("frame",
-											   &fake_tap,
-											   fake_tap_filter->str,
-											   NULL, NULL, NULL);
+                                               &fake_tap,
+                                               fake_tap_filter->str,
+                                               0, /* XXX - do we need the protocol tree or columns? */
+                                               NULL, NULL, NULL);
 
         if (error) {
             report_failure("while registering lua_fake_tap:\n%s",error->str);
diff --git a/epan/wslua/wslua_listener.c b/epan/wslua/wslua_listener.c
index 22548849b4..f281f42204 100644
--- a/epan/wslua/wslua_listener.c
+++ b/epan/wslua/wslua_listener.c
@@ -44,10 +44,11 @@ int tap_packet_cb_error_handler(lua_State* L) {
     static gchar* last_error = NULL;
     static int repeated = 0;
     static int next = 2;
-	const gchar* where =  (lua_pinfo) ?
-		ep_strdup_printf("Lua: on packet %i Error During execution of Listener Packet Callback",lua_pinfo->fd->num) :
-		ep_strdup_printf("Lua: Error During execution of Listener Packet Callback") ;
-	
+    const gchar* where =  (lua_pinfo) ?
+
+    ep_strdup_printf("Lua: on packet %i Error During execution of Listener Packet Callback",lua_pinfo->fd->num) :
+    ep_strdup_printf("Lua: Error During execution of Listener Packet Callback") ;
+    
     /* show the error the 1st, 3rd, 5th, 9th, 17th, 33th... time it appears to avoid window flooding */ 
     /* XXX the last series of identical errors won't be shown (the user however gets at least one message) */
     
@@ -81,7 +82,7 @@ int tap_packet_cb_error_handler(lua_State* L) {
 int lua_tap_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data) {
     Listener tap = tapdata;
     int retval = 0;
-	
+    
     if (tap->packet_ref == LUA_NOREF) return 0;
 
     lua_settop(tap->L,0);
@@ -92,22 +93,22 @@ int lua_tap_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const
     push_Pinfo(tap->L, pinfo);
     push_Tvb(tap->L, edt->tvb);
     
-	if (tap->extractor) {
-		tap->extractor(tap->L,data);
-	} else {
-		lua_pushnil(tap->L);
-	}
-	
+    if (tap->extractor) {
+        tap->extractor(tap->L,data);
+    } else {
+        lua_pushnil(tap->L);
+    }
+    
     lua_pinfo = pinfo; 
     lua_tvb = edt->tvb;
     lua_tree = g_malloc(sizeof(struct _wslua_treeitem));
-	lua_tree->tree = edt->tree;
-	lua_tree->item = NULL;
-	lua_tree->expired = FALSE;
+    lua_tree->tree = edt->tree;
+    lua_tree->item = NULL;
+    lua_tree->expired = FALSE;
     
     switch ( lua_pcall(tap->L,3,1,1) ) {
         case 0:
-			retval = luaL_optint(tap->L,-1,1);
+            retval = luaL_optint(tap->L,-1,1);
             break;
         case LUA_ERRRUN:
             break;
@@ -190,18 +191,18 @@ void lua_tap_draw(void *tapdata) {
 }
 
 WSLUA_CONSTRUCTOR Listener_new(lua_State* L) {
-	/* Creates a new Listener listener */
+    /* Creates a new Listener listener */
 #define WSLUA_OPTARG_Listener_new_TAP 1 /* The name of this tap */
 #define WSLUA_OPTARG_Listener_new_FILTER 2 /* A filter that when matches the tap.packet function gets called (use nil to be called for every packet) */
 
     const gchar* tap_type = luaL_optstring(L,WSLUA_OPTARG_Listener_new_TAP,"frame");
     const gchar* filter = luaL_optstring(L,WSLUA_OPTARG_Listener_new_FILTER,NULL);
-	Listener tap;
+    Listener tap;
     GString* error;
 
     tap = g_malloc(sizeof(struct _wslua_tap));
     
-	tap->name = g_strdup(tap_type);
+    tap->name = g_strdup(tap_type);
     tap->filter = filter ? g_strdup(filter) : NULL;
     tap->extractor = wslua_get_tap_extractor(tap_type);
     tap->L = L;
@@ -209,13 +210,20 @@ WSLUA_CONSTRUCTOR Listener_new(lua_State* L) {
     tap->draw_ref = LUA_NOREF;
     tap->init_ref = LUA_NOREF;
     
-    error = register_tap_listener(tap_type, tap, tap->filter, lua_tap_reset, lua_tap_packet, lua_tap_draw);
+    /*
+     * XXX - do all Lua taps require the protocol tree?  If not, it might
+     * be useful to have a way to indicate whether any do.
+     *
+     * XXX - do any Lua taps require the columns?  If so, we either need
+     * to request them for this tap, or do so if any Lua taps require them.
+     */
+    error = register_tap_listener(tap_type, tap, tap->filter, TL_REQUIRES_PROTO_TREE, lua_tap_reset, lua_tap_packet, lua_tap_draw);
 
     if (error) {
         g_free(tap->filter);
         g_free(tap->name);
         g_free(tap);
-		/* WSLUA_ERROR(new_tap,"tap registration error"); */
+        /* WSLUA_ERROR(new_tap,"tap registration error"); */
         luaL_error(L,"Error while registering tap:\n%s",error->str);
         g_string_free(error,TRUE); /* XXX LEAK? */
     }
@@ -225,7 +233,7 @@ WSLUA_CONSTRUCTOR Listener_new(lua_State* L) {
 }
 
 WSLUA_METHOD Listener_remove(lua_State* L) {
-	/* Removes a tap listener */
+    /* Removes a tap listener */
     Listener tap = checkListener(L,1);
     
     if (!tap) return 0;
@@ -250,19 +258,19 @@ WSLUA_METAMETHOD Listener_tostring(lua_State* L) {
 
 
 static int Listener_newindex(lua_State* L) { 
-	/* WSLUA_ATTRIBUTE Listener_packet WO A function that will be called once every packet matches the Listener listener filter.
-	
-		function tap.packet(pinfo,tvb,userdata) ... end
-	*/
-	/* WSLUA_ATTRIBUTE Listener_draw WO A function that will be called once every few seconds to redraw the gui objects
-				in tshark this funtion is called oly at the very end of the capture file.
-	
-		function tap.draw(userdata) ... end
-	*/
-	/* WSLUA_ATTRIBUTE Listener_reset WO A function that will be called at the end of the capture run.
-	
-		function tap.reset(userdata) ... end
-	*/
+    /* WSLUA_ATTRIBUTE Listener_packet WO A function that will be called once every packet matches the Listener listener filter.
+    
+        function tap.packet(pinfo,tvb,userdata) ... end
+    */
+    /* WSLUA_ATTRIBUTE Listener_draw WO A function that will be called once every few seconds to redraw the gui objects
+                in tshark this funtion is called oly at the very end of the capture file.
+    
+        function tap.draw(userdata) ... end
+    */
+    /* WSLUA_ATTRIBUTE Listener_reset WO A function that will be called at the end of the capture run.
+    
+        function tap.reset(userdata) ... end
+    */
     Listener tap = shiftListener(L,1);
     const gchar* index = lua_shiftstring(L,1);
     int* refp = NULL;
@@ -305,8 +313,8 @@ static const luaL_reg Listener_meta[] = {
 };
 
 int Listener_register(lua_State* L) {
-	wslua_set_tap_enums(L);
+    wslua_set_tap_enums(L);
     WSLUA_REGISTER_CLASS(Listener);
-	return 1;
+    return 1;
 }