Provide for per-protocol-tree data in the proto_tree code.

Put a hash-table of "interesting" fields in the per-proto-tree data.
The dfilter code records which fields/protocols are "interesting" (by which
I mean, their value or existence is checked). Thus, the proto_tree routines
can create special arrays of field_info*'s that are ready for the dfilter
engine to use during a filter operation.

Also store the "proto_tree_is_visible" boolean, renamed "visible", in
the per-proto-tree data.

Move epan_dissect_t to its own header file to make #include dependencies
easier to handle.

Provide epan_dissect_fill_in_columns(), which accepts just the epan_dissect_t*
as an argument.

epan_dissect_new() needs to be followed by epan_dissect_run() for the
dissection to actually take place. Between those two calls,
epan_dissect_prime_dfilter() can be run 0, 1, or multiple times in order to
prime the empty proto_tree with the "intersesting" fields from the dfilter_t.

svn path=/trunk/; revision=4422

15 files changed, 441 insertions, 218 deletions

diff --git a/epan/Makefile.am b/epan/Makefile.am
index 02e2c2b782..cefe353d0d 100644
--- a/epan/Makefile.am
+++ b/epan/Makefile.am
@@ -2,7 +2,7 @@
 # Automake file for the EPAN library
 # (Ethereal Protocol ANalyzer Library)
 #
-# $Id: Makefile.am,v 1.29 2001/11/22 03:07:06 hagbard Exp $
+# $Id: Makefile.am,v 1.30 2001/12/18 19:09:03 gram Exp $
 #
 # Ethereal - Network traffic analyzer
 # By Gerald Combs <gerald@zing.org>
@@ -46,6 +46,7 @@ libethereal_a_SOURCES = \
 	column-utils.h		\
 	epan.c			\
 	epan.h			\
+	epan_dissect.h	\
 	except.c		\
 	except.h		\
 	exceptions.h		\
diff --git a/epan/dfilter/dfilter-int.h b/epan/dfilter/dfilter-int.h
index c1e6774438..89e1857f8f 100644
--- a/epan/dfilter/dfilter-int.h
+++ b/epan/dfilter/dfilter-int.h
@@ -1,5 +1,5 @@
 /*
- * $Id: dfilter-int.h,v 1.3 2001/02/15 06:22:45 guy Exp $
+ * $Id: dfilter-int.h,v 1.4 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -35,6 +35,8 @@ struct _dfilter_t {
 	int		num_registers;
 	GList		**registers;
 	gboolean	*attempted_load;
+    int         *interesting_fields;
+    int         num_interesting_fields;
 };
 
 typedef struct {
@@ -43,6 +45,7 @@ typedef struct {
 	gboolean	syntax_error;
 	GPtrArray	*insns;
 	GHashTable	*loaded_fields;
+	GHashTable	*interesting_fields;
 	int		next_insn_id;
 	int		next_register;
 } dfwork_t;
diff --git a/epan/dfilter/dfilter.c b/epan/dfilter/dfilter.c
index 0380f15662..1f5743d23e 100644
--- a/epan/dfilter/dfilter.c
+++ b/epan/dfilter/dfilter.c
@@ -1,5 +1,5 @@
 /*
- * $Id: dfilter.c,v 1.5 2001/07/13 00:55:54 guy Exp $
+ * $Id: dfilter.c,v 1.6 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -37,6 +37,7 @@
 #include "gencode.h"
 #include "semcheck.h"
 #include "dfvm.h"
+#include "epan_dissect.h"
 
 
 /* Balanced tree of abbreviations and IDs */
@@ -228,6 +229,10 @@ dfilter_free(dfilter_t *df)
 		free_insns(df->insns);
 	}
 
+    if (df->interesting_fields) {
+        g_free(df->interesting_fields);
+    }
+
 	g_free(df->registers);
 	g_free(df->attempted_load);
 	g_free(df);
@@ -245,6 +250,7 @@ dfwork_new(void)
 	dfw->syntax_error = FALSE;
 	dfw->insns = NULL;
 	dfw->loaded_fields = NULL;
+	dfw->interesting_fields = NULL;
 	dfw->next_insn_id = 0;
 	dfw->next_register = 0;
 
@@ -262,10 +268,15 @@ dfwork_free(dfwork_t *dfw)
 		g_hash_table_destroy(dfw->loaded_fields);
 	}
 
+	if (dfw->interesting_fields) {
+		g_hash_table_destroy(dfw->interesting_fields);
+	}
+
 	if (dfw->insns) {
 		free_insns(dfw->insns);
 	}
 
+
 	g_free(dfw);
 }
 
@@ -333,6 +344,8 @@ dfilter_compile(gchar *text, dfilter_t **dfp)
 		dfilter = dfilter_new();
 		dfilter->insns = dfw->insns;
 		dfw->insns = NULL;
+        dfilter->interesting_fields = dfw_interesting_fields(dfw,
+                &dfilter->num_interesting_fields);
 
 		/* Initialize run-time space */
 		dfilter->num_registers = dfw->next_register;
@@ -378,6 +391,18 @@ dfilter_apply_edt(dfilter_t *df, epan_dissect_t* edt)
 
 
 void
+dfilter_foreach_interesting_field(dfilter_t *df, GFunc func,
+        gpointer user_data)
+{
+    int i;
+
+    for (i = 0; i < df->num_interesting_fields; i++) {
+        func(GINT_TO_POINTER(df->interesting_fields[i]), user_data);
+    }
+}
+                
+
+void
 dfilter_dump(dfilter_t *df)
 {
 	dfvm_dump(stdout, df->insns);
diff --git a/epan/dfilter/dfilter.h b/epan/dfilter/dfilter.h
index afd93fb824..49eba9c5db 100644
--- a/epan/dfilter/dfilter.h
+++ b/epan/dfilter/dfilter.h
@@ -1,5 +1,5 @@
 /*
- * $Id: dfilter.h,v 1.2 2001/02/01 20:31:18 gram Exp $
+ * $Id: dfilter.h,v 1.3 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -25,12 +25,14 @@
 #define DFILTER_H
 
 #include <glib.h>
-#include "epan.h"
-#include "proto.h"
 
 /* Passed back to user */
 typedef struct _dfilter_t dfilter_t;
 
+#include "epan.h"
+#include "proto.h"
+
+
 /* Module-level initialization */
 void
 dfilter_init(void);
@@ -75,6 +77,10 @@ dfilter_apply_edt(dfilter_t *df, epan_dissect_t* edt);
 gboolean
 dfilter_apply(dfilter_t *df, tvbuff_t *tvb, proto_tree *tree);
 
+/* Run a callback for each interesting field in the dfilter. */
+void
+dfilter_foreach_interesting_field(dfilter_t *df, GFunc func,
+        gpointer user_data);
 
 /* Print bytecode of dfilter to stdout */
 void
diff --git a/epan/dfilter/dfvm.c b/epan/dfilter/dfvm.c
index bc1c48c21d..02bf948a5c 100644
--- a/epan/dfilter/dfvm.c
+++ b/epan/dfilter/dfvm.c
@@ -1,5 +1,5 @@
 /*
- * $Id: dfvm.c,v 1.4 2001/12/13 05:55:23 gram Exp $
+ * $Id: dfvm.c,v 1.5 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -211,6 +211,9 @@ read_tree(dfilter_t *df, proto_tree *tree, int field_id, int reg)
 	if (!finfos) {
 		return FALSE;
 	}
+    else if (g_ptr_array_len(finfos) == 0) {
+        return FALSE;
+    }
 
 	len = finfos->len;
 	for (i = 0; i < len; i++) {
@@ -218,7 +221,6 @@ read_tree(dfilter_t *df, proto_tree *tree, int field_id, int reg)
 		fvalues = g_list_prepend(fvalues, finfo->value);
 	}
 	fvalues = g_list_reverse(fvalues);
-	g_ptr_array_free(finfos, TRUE);
 
 	df->registers[reg] = fvalues;
 	return TRUE;
diff --git a/epan/dfilter/gencode.c b/epan/dfilter/gencode.c
index cf3e1d5787..d8d0119005 100644
--- a/epan/dfilter/gencode.c
+++ b/epan/dfilter/gencode.c
@@ -1,5 +1,5 @@
 /*
- * $Id: gencode.c,v 1.3 2001/02/27 19:23:28 gram Exp $
+ * $Id: gencode.c,v 1.4 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -57,7 +57,7 @@ dfw_append_read_tree(dfwork_t *dfw, int field_id)
 	 * can re-use registers. */
 	reg = GPOINTER_TO_UINT(
 			g_hash_table_lookup(dfw->loaded_fields,
-			GUINT_TO_POINTER(field_id)));
+			GINT_TO_POINTER(field_id)));
 	if (reg) {
 		/* Reg's are stored in has as reg+1, so
 		 * that the non-existence of a field_id in
@@ -70,6 +70,10 @@ dfw_append_read_tree(dfwork_t *dfw, int field_id)
 		g_hash_table_insert(dfw->loaded_fields,
 			GUINT_TO_POINTER(field_id),
 			GUINT_TO_POINTER(reg + 1));
+
+        /* Record the FIELD_ID in hash of interesting fields. */
+        g_hash_table_insert(dfw->interesting_fields,
+            GINT_TO_POINTER(field_id), GUINT_TO_POINTER(TRUE));
 	}
 
 	insn = dfvm_insn_new(READ_TREE);
@@ -232,6 +236,11 @@ gen_test(dfwork_t *dfw, stnode_t *st_node)
 			insn = dfvm_insn_new(CHECK_EXISTS);
 			insn->arg1 = val1;
 			dfw_append_insn(dfw, insn);
+
+            /* Record the FIELD_ID in hash of interesting fields. */
+            g_hash_table_insert(dfw->interesting_fields,
+                GINT_TO_POINTER(hfinfo->id), GUINT_TO_POINTER(TRUE));
+
 			break;
 
 		case TEST_OP_NOT:
@@ -312,7 +321,44 @@ dfw_gencode(dfwork_t *dfw)
 {
 	dfw->insns = g_ptr_array_new();
 	dfw->loaded_fields = g_hash_table_new(g_direct_hash, g_direct_equal);
+	dfw->interesting_fields = g_hash_table_new(g_direct_hash, g_direct_equal);
 	gencode(dfw, dfw->st_root);
 	dfw_append_insn(dfw, dfvm_insn_new(RETURN));
 }
 
+
+
+typedef struct {
+    int i;
+    int *fields;
+} hash_key_iterator;
+ 
+static void
+get_hash_key(gpointer key, gpointer value, gpointer user_data)
+{
+    int field_id = GPOINTER_TO_INT(key);
+    hash_key_iterator *hki = user_data;
+
+    hki->fields[hki->i] = field_id;
+    hki->i++;
+}
+
+int*
+dfw_interesting_fields(dfwork_t *dfw, int *caller_num_fields)
+{
+    int num_fields = g_hash_table_size(dfw->interesting_fields);
+
+    hash_key_iterator hki;
+
+    if (num_fields == 0) {
+        *caller_num_fields = 0;
+        return NULL;
+    }
+
+    hki.fields = g_new(int, num_fields);
+    hki.i = 0;
+        
+    g_hash_table_foreach(dfw->interesting_fields, get_hash_key, &hki);
+    *caller_num_fields = num_fields;
+    return hki.fields;
+}
diff --git a/epan/dfilter/gencode.h b/epan/dfilter/gencode.h
index db56b9082c..2148b2be58 100644
--- a/epan/dfilter/gencode.h
+++ b/epan/dfilter/gencode.h
@@ -4,4 +4,7 @@
 void
 dfw_gencode(dfwork_t *dfw);
 
+int*
+dfw_interesting_fields(dfwork_t *dfw, int *caller_num_fields);
+
 #endif
diff --git a/epan/dfilter/semcheck.c b/epan/dfilter/semcheck.c
index 025d471baa..5afb7b6b0a 100644
--- a/epan/dfilter/semcheck.c
+++ b/epan/dfilter/semcheck.c
@@ -1,5 +1,5 @@
 /*
- * $Id: semcheck.c,v 1.6 2001/11/02 10:09:49 guy Exp $
+ * $Id: semcheck.c,v 1.7 2001/12/18 19:09:06 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -32,6 +32,7 @@
 #include "sttype-test.h"
 
 #include "exceptions.h"
+#include "packet.h"
 
 static void
 semcheck(dfwork_t *dfw, stnode_t *st_node);
diff --git a/epan/epan.c b/epan/epan.c
index 20edfb4b42..4be784e8b2 100644
--- a/epan/epan.c
+++ b/epan/epan.c
@@ -1,6 +1,6 @@
 /* epan.h
  *
- * $Id: epan.c,v 1.14 2001/12/16 22:16:13 guy Exp $
+ * $Id: epan.c,v 1.15 2001/12/18 19:09:03 gram Exp $
  *
  * Ethereal Protocol Analyzer Library
  *
@@ -11,14 +11,13 @@
 #endif
 
 #include <glib.h>
-#include <epan.h>
+#include "epan.h"
+#include "epan_dissect.h"
 
 #include "conversation.h"
-#include "dfilter/dfilter.h"
 #include "except.h"
 #include "packet.h"
-#include "proto.h"
-#include "tvbuff.h"
+#include "column-utils.h"
 
 /*
  * XXX - this takes the plugin directory as an argument, because
@@ -74,37 +73,34 @@ epan_conversation_init(void)
 
 
 epan_dissect_t*
-epan_dissect_new(void* pseudo_header, const guint8* data, frame_data *fd,
-		gboolean create_proto_tree, gboolean proto_tree_visible,
-		column_info *cinfo)
+epan_dissect_new(gboolean create_proto_tree, gboolean proto_tree_visible)
 {
 	epan_dissect_t	*edt;
 
 	edt = g_new(epan_dissect_t, 1);
 
-	/* start with empty data source list */
-	if ( fd->data_src)
-                g_slist_free( fd->data_src);
-        fd->data_src = 0;
-
-	/*
-	 * Set the global "proto_tree_is_visible" to control whether
-	 * to fill in the text representation field in the protocol
-	 * tree fields.
-	 */
-	proto_tree_is_visible = proto_tree_visible;
 	if (create_proto_tree) {
 		edt->tree = proto_tree_create_root();
+        proto_tree_set_visible(edt->tree, proto_tree_visible);
 	}
 	else {
 		edt->tree = NULL;
 	}
 
-	dissect_packet(edt, pseudo_header, data, fd, cinfo);
+	return edt;
+}
 
-	proto_tree_is_visible = FALSE;
+void
+epan_dissect_run(epan_dissect_t *edt, void* pseudo_header,
+        const guint8* data, frame_data *fd, column_info *cinfo)
+{
+	/* start with empty data source list */
+	if (fd->data_src) {
+        g_slist_free(fd->data_src);
+    }
+    fd->data_src = NULL;
 
-	return edt;
+	dissect_packet(edt, pseudo_header, data, fd, cinfo);
 }
 
 
@@ -122,3 +118,24 @@ epan_dissect_free(epan_dissect_t* edt)
 
 	g_free(edt);
 }
+
+static void
+prime_dfilter(gpointer data, gpointer user_data)
+{
+    int hfid = GPOINTER_TO_INT(data);
+    proto_tree *tree = user_data;
+
+    proto_tree_prime_hfid(tree, hfid);
+}
+
+void
+epan_dissect_prime_dfilter(epan_dissect_t *edt, dfilter_t* dfcode)
+{
+    dfilter_foreach_interesting_field(dfcode, prime_dfilter, edt->tree);
+}
+
+void
+epan_dissect_fill_in_columns(epan_dissect_t *edt)
+{
+    fill_in_columns(&edt->pi);
+}
diff --git a/epan/epan.h b/epan/epan.h
index f33cb1034e..3a3197f540 100644
--- a/epan/epan.h
+++ b/epan/epan.h
@@ -1,21 +1,37 @@
 /* epan.h
  *
- * $Id: epan.h,v 1.11 2001/12/16 22:16:13 guy Exp $
+ * $Id: epan.h,v 1.12 2001/12/18 19:09:03 gram Exp $
  *
  * Ethereal Protocol Analyzer Library
  *
+ * Copyright (c) 2001 by Gerald Combs <gerald@ethereal.com>
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
  */
 
 #ifndef EPAN_H
 #define EPAN_H
 
 #include <glib.h>
+#include "frame_data.h"
+#include "column_info.h"
 
-struct _epan_dissect_t;
+typedef struct _epan_dissect_t epan_dissect_t;
 
-/* XXX - for now */
-#include "packet.h"
-#include "packet_info.h"
+#include "dfilter/dfilter.h"
 
 void epan_init(const char * plugindir, void (register_all_protocols)(void),
 	       void (register_all_handoffs)(void));
@@ -40,24 +56,18 @@ void
 epan_free(epan_t*);
 
 
+epan_dissect_t*
+epan_dissect_new(gboolean create_proto_tree, gboolean proto_tree_visible);
 
+void
+epan_dissect_run(epan_dissect_t *edt, void* pseudo_header,
+        const guint8* data, frame_data *fd, column_info *cinfo);
 
-/* Dissection of a single byte array. Holds tvbuff info as
- * well as proto_tree info. As long as the epan_dissect_t for a byte
- * array is in existence, you must not free or move that byte array,
- * as the structures that the epan_dissect_t contains might have pointers
- * to addresses in your byte array.
- */
-typedef struct _epan_dissect_t {
-	tvbuff_t	*tvb;
-	proto_tree	*tree;
-	packet_info	pi;
-} epan_dissect_t;
+void
+epan_dissect_prime_dfilter(epan_dissect_t *edt, dfilter_t*);
 
-epan_dissect_t*
-epan_dissect_new(void* pseudo_header, const guint8* data, frame_data *fd,
-		gboolean create_proto_tree, gboolean proto_tree_visible,
-		column_info *cinfo);
+void
+epan_dissect_fill_in_columns(epan_dissect_t *edt);
 
 void
 epan_dissect_free(epan_dissect_t* edt);
diff --git a/epan/epan_dissect.h b/epan/epan_dissect.h
new file mode 100644
index 0000000000..424ea60484
--- /dev/null
+++ b/epan/epan_dissect.h
@@ -0,0 +1,44 @@
+/* epan_dissect.h
+ *
+ * $Id: epan_dissect.h,v 1.1 2001/12/18 19:09:03 gram Exp $
+ *
+ * Ethereal Protocol Analyzer Library
+ *
+ * Copyright (c) 2001 by Gerald Combs <gerald@ethereal.com>
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifndef EPAN_DISSECT_H
+#define EPAN_DISSECT_H
+
+#include "tvbuff.h"
+#include "proto.h"
+#include "packet_info.h"
+
+/* Dissection of a single byte array. Holds tvbuff info as
+ * well as proto_tree info. As long as the epan_dissect_t for a byte
+ * array is in existence, you must not free or move that byte array,
+ * as the structures that the epan_dissect_t contains might have pointers
+ * to addresses in your byte array.
+ */
+struct _epan_dissect_t {
+	tvbuff_t	*tvb;
+	proto_tree	*tree;
+	packet_info	pi;
+};
+
+
+#endif /* EPAN_DISSECT_H */
diff --git a/epan/packet.c b/epan/packet.c
index b6f299a0a1..6ef976a430 100644
--- a/epan/packet.c
+++ b/epan/packet.c
@@ -1,7 +1,7 @@
 /* packet.c
  * Routines for packet disassembly
  *
- * $Id: packet.c,v 1.54 2001/12/10 00:26:16 guy Exp $
+ * $Id: packet.c,v 1.55 2001/12/18 19:09:03 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -79,6 +79,7 @@
 #include "resolv.h"
 #include "tvbuff.h"
 #include "plugins.h"
+#include "epan_dissect.h"
 
 static gint proto_malformed = -1;
 static dissector_handle_t frame_handle = NULL;
diff --git a/epan/packet.h b/epan/packet.h
index 812e653cbf..5d4a048c75 100644
--- a/epan/packet.h
+++ b/epan/packet.h
@@ -1,7 +1,7 @@
 /* packet.h
  * Definitions for packet disassembly structures and routines
  *
- * $Id: packet.h,v 1.47 2001/12/10 00:26:16 guy Exp $
+ * $Id: packet.h,v 1.48 2001/12/18 19:09:03 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -226,7 +226,7 @@ extern void init_all_protocols(void);
 /*
  * Dissectors should never modify the packet data.
  */
-extern void dissect_packet(struct _epan_dissect_t *edt,
+extern void dissect_packet(epan_dissect_t *edt,
     union wtap_pseudo_header *pseudo_header, const u_char *pd,
     frame_data *fd, column_info *cinfo);
 
diff --git a/epan/proto.c b/epan/proto.c
index 0db8366551..56e68454b2 100644
--- a/epan/proto.c
+++ b/epan/proto.c
@@ -1,7 +1,7 @@
 /* proto.c
  * Routines for protocol tree
  *
- * $Id: proto.c,v 1.47 2001/12/07 03:39:26 gram Exp $
+ * $Id: proto.c,v 1.48 2001/12/18 19:09:04 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -73,11 +73,12 @@ static proto_item*
 proto_tree_add_node(proto_tree *tree, field_info *fi);
 
 static field_info *
-alloc_field_info(int hfindex, tvbuff_t *tvb, gint start, gint length);
+alloc_field_info(proto_tree *tree, int hfindex, tvbuff_t *tvb,
+        gint start, gint length);
 
 static proto_item *
-proto_tree_add_pi(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint start, gint length,
-		field_info **pfi);
+proto_tree_add_pi(proto_tree *tree, int hfindex, tvbuff_t *tvb,
+        gint start, gint length, field_info **pfi);
 static void
 proto_tree_set_representation(proto_item *pi, const char *format, va_list ap);
 
@@ -138,6 +139,12 @@ typedef struct {
 /* List of all protocols */
 static GList *protocols;
 
+#define INITIAL_NUM_PROTOCOL_HFINFO     200
+#define INITIAL_NUM_FIELD_INFO          100
+#define INITIAL_NUM_PROTO_NODE          100
+#define INITIAL_NUM_ITEM_LABEL          100
+
+
 /* Contains information about protocols and header fields. Used when
  * dissectors register their data */
 static GMemChunk *gmc_hfinfo = NULL;
@@ -146,6 +153,9 @@ static GMemChunk *gmc_hfinfo = NULL;
  * proto_tree_add_item.  */
 static GMemChunk *gmc_field_info = NULL;
 
+/* Contains the space for proto_nodes. */
+static GMemChunk *gmc_proto_node = NULL;
+
 /* String space for protocol and field items for the GUI */
 static GMemChunk *gmc_item_labels = NULL;
 
@@ -160,12 +170,6 @@ gboolean	*tree_is_expanded;
 /* Number of elements in that array. */
 int		num_tree_types;
 
-/* Is the parsing being done for a visible proto_tree or an invisible one?
- * By setting this correctly, the proto_tree creation is sped up by not
- * having to call vsnprintf and copy strings around.
- */
-gboolean proto_tree_is_visible = FALSE;
-
 /* initialize data structures and register protocols and fields */
 void
 proto_init(const char *plugin_dir,void (register_all_protocols)(void),
@@ -181,6 +185,8 @@ proto_init(const char *plugin_dir,void (register_all_protocols)(void),
 		g_mem_chunk_destroy(gmc_hfinfo);
 	if (gmc_field_info)
 		g_mem_chunk_destroy(gmc_field_info);
+	if (gmc_proto_node)
+		g_mem_chunk_destroy(gmc_proto_node);
 	if (gmc_item_labels)
 		g_mem_chunk_destroy(gmc_item_labels);
 	if (gpa_hfinfo)
@@ -189,13 +195,25 @@ proto_init(const char *plugin_dir,void (register_all_protocols)(void),
 		g_free(tree_is_expanded);
 
 	gmc_hfinfo = g_mem_chunk_new("gmc_hfinfo",
-		sizeof(header_field_info), 50 * sizeof(header_field_info), G_ALLOC_ONLY);
+		sizeof(header_field_info),
+        INITIAL_NUM_PROTOCOL_HFINFO * sizeof(header_field_info),
+        G_ALLOC_ONLY);
+
 	gmc_field_info = g_mem_chunk_new("gmc_field_info",
-		sizeof(struct field_info), 200 * sizeof(struct field_info),
+		sizeof(field_info),
+        INITIAL_NUM_FIELD_INFO * sizeof(field_info),
 		G_ALLOC_AND_FREE);
+
+	gmc_proto_node = g_mem_chunk_new("gmc_proto_node",
+		sizeof(proto_node),
+        INITIAL_NUM_PROTO_NODE * sizeof(proto_node),
+		G_ALLOC_AND_FREE);
+
 	gmc_item_labels = g_mem_chunk_new("gmc_item_labels",
-		ITEM_LABEL_LENGTH, 20 * ITEM_LABEL_LENGTH,
+		ITEM_LABEL_LENGTH,
+        INITIAL_NUM_ITEM_LABEL* ITEM_LABEL_LENGTH,
 		G_ALLOC_AND_FREE);
+
 	gpa_hfinfo = g_ptr_array_new();
 
 	/* Allocate "tree_is_expanded", with one element for ETT_NONE,
@@ -248,10 +266,14 @@ proto_cleanup(void)
 		g_mem_chunk_destroy(gmc_hfinfo);
 	if (gmc_field_info)
 		g_mem_chunk_destroy(gmc_field_info);
+	if (gmc_proto_node)
+		g_mem_chunk_destroy(gmc_proto_node);
 	if (gmc_item_labels)
 		g_mem_chunk_destroy(gmc_item_labels);
 	if (gpa_hfinfo)
 		g_ptr_array_free(gpa_hfinfo, TRUE);
+	if (tree_is_expanded != NULL)
+		g_free(tree_is_expanded);
 
 	/* Cleanup the ftype subsystem */
 	ftypes_cleanup();
@@ -261,8 +283,11 @@ proto_cleanup(void)
 void
 proto_tree_free(proto_tree *tree)
 {
+    /* Free all the data pointed to by the tree. */
 	g_node_traverse((GNode*)tree, G_IN_ORDER, G_TRAVERSE_ALL, -1,
 		proto_tree_free_node, NULL);
+
+    /* Then free the tree. */
 	g_node_destroy((GNode*)tree);
 }
 
@@ -273,20 +298,69 @@ free_field_info(void *fi)
 	g_mem_chunk_free(gmc_field_info, (field_info*)fi);
 }
 
-static gboolean
-proto_tree_free_node(GNode *node, gpointer data)
+static void
+free_GPtrArray_value(gpointer key, gpointer value, gpointer user_data)
 {
-	field_info *fi = (field_info*) (node->data);
+    GPtrArray   *ptrs = value;
 
-	if (fi != NULL) {
-		if (fi->representation) {
-			g_mem_chunk_free(gmc_item_labels, fi->representation);
+    g_ptr_array_free(ptrs, TRUE);
+}
+
+static void
+free_node_tree_data(tree_data_t *tree_data)
+{
+        /* Free all the GPtrArray's in the interesting_hfids hash. */
+        g_hash_table_foreach(tree_data->interesting_hfids,
+            free_GPtrArray_value, NULL);
+
+        /* And then destroy the hash. */
+        g_hash_table_destroy(tree_data->interesting_hfids);
+
+        /* And finally the tree_data_t itself. */
+        g_free(tree_data);
+}
+
+static void
+free_node_field_info(field_info* finfo)
+{
+		if (finfo->representation) {
+			g_mem_chunk_free(gmc_item_labels, finfo->representation);
 		}
-		fvalue_free(fi->value);
-		free_field_info(fi);
+		fvalue_free(finfo->value);
+		free_field_info(finfo);
+}
+
+static gboolean
+proto_tree_free_node(GNode *node, gpointer data)
+{
+	field_info *finfo = PITEM_FINFO(node);
+
+    if (finfo == NULL) {
+        /* This is the root GNode. Destroy the per-tree data.
+         * There is no field_info to destroy. */
+        free_node_tree_data(PTREE_DATA(node));
+    }
+    else {
+        /* This is a child GNode. Don't free the per-tree data, but
+         * do free the field_info data. */
+        free_node_field_info(finfo);
 	}
+
+    /* Free the proto_node. */
+	g_mem_chunk_free(gmc_proto_node, GNODE_PNODE(node));
+
 	return FALSE; /* FALSE = do not end traversal of GNode tree */
-}	
+}
+
+/* Is the parsing being done for a visible proto_tree or an invisible one?
+ * By setting this correctly, the proto_tree creation is sped up by not
+ * having to call vsnprintf and copy strings around.
+ */
+void
+proto_tree_set_visible(proto_tree *tree, gboolean visible)
+{
+    PTREE_DATA(tree)->visible = visible;
+}
 
 /* Finds a record in the hf_info_records array by id. */
 header_field_info*
@@ -451,11 +525,13 @@ proto_tree_add_item(proto_tree *tree, int hfindex, tvbuff_t *tvb,
 	guint32		value, n;
 	char		*string;
 	int		found_length;
+    GHashTable  *hash;
+    GPtrArray   *ptrs;
 
 	if (!tree)
 		return(NULL);
 
-	new_fi = alloc_field_info(hfindex, tvb, start, length);
+	new_fi = alloc_field_info(tree, hfindex, tvb, start, length);
 
 	if (new_fi == NULL)
 		return(NULL);
@@ -574,6 +650,14 @@ proto_tree_add_item(proto_tree *tree, int hfindex, tvbuff_t *tvb,
 	 * raised by a tvbuff access method doesn't leave junk in the proto_tree. */
 	pi = proto_tree_add_node(tree, new_fi);
 
+    /* If the proto_tree wants to keep a record of this finfo
+     * for quick lookup, then record it. */
+    hash = PTREE_DATA(tree)->interesting_hfids;
+    ptrs = g_hash_table_lookup(hash, GINT_TO_POINTER(hfindex));
+    if (ptrs) {
+        g_ptr_array_add(ptrs, new_fi);
+    }
+
 	return pi;
 }
 
@@ -588,7 +672,7 @@ proto_tree_add_item_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb,
 	if (pi == NULL)
 		return(NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -691,7 +775,7 @@ proto_tree_add_bytes_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint s
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -767,7 +851,7 @@ proto_tree_add_time_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint st
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -830,7 +914,7 @@ proto_tree_add_ipxnet_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -893,7 +977,7 @@ proto_tree_add_ipv4_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint st
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -956,7 +1040,7 @@ proto_tree_add_ipv6_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint st
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1047,7 +1131,7 @@ proto_tree_add_string_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1122,7 +1206,7 @@ proto_tree_add_ether_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint s
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1191,7 +1275,7 @@ proto_tree_add_boolean_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1254,7 +1338,7 @@ proto_tree_add_double_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1326,7 +1410,7 @@ proto_tree_add_uint_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint st
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1413,7 +1497,7 @@ proto_tree_add_int_hidden(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint sta
 	if (pi == NULL)
 		return (NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->visible = FALSE;
 
 	return pi;
@@ -1464,12 +1548,17 @@ proto_tree_set_int(field_info *fi, gint32 value)
 static proto_item *
 proto_tree_add_node(proto_tree *tree, field_info *fi)
 {
-	proto_item *pi;
+	GNode *new_gnode;
+    proto_node *pnode;
 
-	pi = (proto_item*) g_node_new(fi);
-	g_node_append((GNode*)tree, (GNode*)pi);
+    pnode = g_mem_chunk_alloc(gmc_proto_node);
+    pnode->finfo = fi;
+    pnode->tree_data = PTREE_DATA(tree);
 
-	return pi;
+    new_gnode = g_node_new(pnode);
+    g_node_append((GNode*)tree, new_gnode);
+
+    return (proto_item*) new_gnode;
 }
 
 
@@ -1481,13 +1570,24 @@ proto_tree_add_pi(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint start, gint
 {
 	proto_item	*pi;
 	field_info	*fi;
+    GHashTable  *hash;
+    GPtrArray   *ptrs;
 
 	if (!tree)
 		return(NULL);
 
-	fi = alloc_field_info(hfindex, tvb, start, length);
+	fi = alloc_field_info(tree, hfindex, tvb, start, length);
 	pi = proto_tree_add_node(tree, fi);
 
+    /* If the proto_tree wants to keep a record of this finfo
+     * for quick lookup, then record it. */
+    hash = PTREE_DATA(tree)->interesting_hfids;
+    ptrs = g_hash_table_lookup(hash, GINT_TO_POINTER(hfindex));
+    if (ptrs) {
+        g_ptr_array_add(ptrs, fi);
+    }
+
+    /* Does the caller want to know the fi pointer? */
 	if (pfi) {
 		*pfi = fi;
 	}
@@ -1496,7 +1596,7 @@ proto_tree_add_pi(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint start, gint
 }
 
 static field_info *
-alloc_field_info(int hfindex, tvbuff_t *tvb, gint start, gint length)
+alloc_field_info(proto_tree *tree, int hfindex, tvbuff_t *tvb, gint start, gint length)
 {
 	field_info	*fi;
 
@@ -1517,7 +1617,7 @@ alloc_field_info(int hfindex, tvbuff_t *tvb, gint start, gint length)
 	}
 	fi->length = length;
 	fi->tree_type = ETT_NONE;
-	fi->visible = proto_tree_is_visible;
+	fi->visible = PTREE_DATA(tree)->visible;
 	fi->representation = NULL;
 
 	fi->value = fvalue_new(fi->hfinfo->type);
@@ -1537,7 +1637,7 @@ alloc_field_info(int hfindex, tvbuff_t *tvb, gint start, gint length)
 static void
 proto_tree_set_representation(proto_item *pi, const char *format, va_list ap)
 {
-	field_info *fi = (field_info*) (((GNode*)pi)->data);
+	field_info *fi = PITEM_FINFO(pi);
 
 	if (fi->visible) {
 		fi->representation = g_mem_chunk_alloc(gmc_item_labels);
@@ -1556,7 +1656,7 @@ proto_item_set_text(proto_item *pi, const char *format, ...)
 		return;
 	}
 
-	fi = (field_info *)(((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 
 	if (fi->representation)
 		g_mem_chunk_free(gmc_item_labels, fi->representation);
@@ -1578,7 +1678,7 @@ proto_item_append_text(proto_item *pi, const char *format, ...)
 		return;
 	}
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 
 	if (fi->visible) {
 		va_start(ap, format);
@@ -1603,21 +1703,45 @@ proto_item_set_len(proto_item *pi, gint length)
 	
 	if (pi == NULL)
 		return;
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	fi->length = length;
 }
 
 int
 proto_item_get_len(proto_item *pi)
 {
-	field_info *fi = (field_info*) (((GNode*)pi)->data);
+	field_info *fi = PITEM_FINFO(pi);
 	return fi->length;
 }
 
 proto_tree*
 proto_tree_create_root(void)
 {
-	return (proto_tree*) g_node_new(NULL);
+    proto_node  *pnode;
+
+    /* Initialize the proto_node */
+    pnode = g_mem_chunk_alloc(gmc_proto_node);
+    pnode->finfo = NULL;
+    pnode->tree_data = g_new(tree_data_t, 1);
+
+    /* Initialize the tree_data_t */
+    pnode->tree_data->interesting_hfids =
+        g_hash_table_new(g_direct_hash, g_direct_equal);
+
+    /* Set the default to FALSE so it's easier to
+     * find errors; if we expect to see the protocol tree
+     * but for some reason the default 'visible' is not
+     * changed, then we'll find out very quickly. */
+    pnode->tree_data->visible = FALSE;
+
+	return (proto_tree*) g_node_new(pnode);
+}
+
+void
+proto_tree_prime_hfid(proto_tree *tree, int hfid)
+{
+    g_hash_table_insert(PTREE_DATA(tree)->interesting_hfids,
+            GINT_TO_POINTER(hfid), g_ptr_array_new());
 }
 
 proto_tree*
@@ -1627,7 +1751,7 @@ proto_item_add_subtree(proto_item *pi,  gint idx) {
 	if (!pi)
 		return(NULL);
 
-	fi = (field_info*) (((GNode*)pi)->data);
+	fi = PITEM_FINFO(pi);
 	g_assert(idx >= 0 && idx < num_tree_types);
 	fi->tree_type = idx;
 	return (proto_tree*) pi;
@@ -2594,7 +2718,7 @@ proto_find_protocol_multi(proto_tree* tree, GNodeTraverseFunc callback,
 static gboolean
 traverse_subtree_for_field(GNode *node, gpointer data)
 {
-	field_info		*fi = (field_info*) (node->data);
+	field_info *fi = PITEM_FINFO(node);
 	proto_tree_search_info	*sinfo = (proto_tree_search_info*) data;
 
 	if (fi) { /* !fi == the top most container node which holds nothing */
@@ -2606,126 +2730,37 @@ traverse_subtree_for_field(GNode *node, gpointer data)
 	return FALSE; /* keep traversing */
 }
 
-static gboolean
-check_for_protocol_or_field_id(GNode *node, gpointer data)
-{
-	field_info		*fi = (field_info*) (node->data);
-	proto_tree_search_info	*sinfo = (proto_tree_search_info*) data;
-	header_field_info	*hfinfo;
-
-	if (fi) { /* !fi == the top most container node which holds nothing */
-		/* Is this field one of the fields in the specified list
-		 * of fields? */
-		for (hfinfo = sinfo->target; hfinfo != NULL;
-		    hfinfo = hfinfo->same_name_next) {
-			if (fi->hfinfo == hfinfo) {
-				sinfo->result.node = node;
-				return TRUE; /* halt traversal */
-			}
-		}
-	}
-	return FALSE; /* keep traversing */
-}
-
 /* Looks for a protocol or a field in a proto_tree. Returns TRUE if
  * it exists anywhere, or FALSE if it exists nowhere. */
 gboolean
 proto_check_for_protocol_or_field(proto_tree* tree, int id)
 {
-	proto_tree_search_info	sinfo;
-	header_field_info	*hfinfo;
-
-	hfinfo = proto_registrar_get_nth(id);
-
-	/* Find the first entry on the list of fields with the same
-	 * name as this field. */
-	while (hfinfo->same_name_prev != NULL)
-		hfinfo = hfinfo->same_name_prev;
-
-	sinfo.target		= hfinfo;
-	sinfo.result.node	= NULL;
-	sinfo.traverse_func	= check_for_protocol_or_field_id;
-	sinfo.halt_on_first_hit	= TRUE;
-
-	/* do a quicker check if target is a protocol */
-	if (proto_registrar_is_protocol(id) == TRUE) {
-		proto_find_protocol_multi(tree, check_for_protocol_or_field_id, &sinfo);
-	}
-	else {
-		/* Go through each protocol subtree. */
-		g_node_traverse((GNode*)tree, G_IN_ORDER, G_TRAVERSE_ALL, 2,
-						traverse_subtree_for_field, &sinfo);
-	}
-
-	if (sinfo.result.node)
-		return TRUE;
-	else
-		return FALSE;
-}
-
-
-
-static gboolean
-get_finfo_ptr_array(GNode *node, gpointer data)
-{
-	field_info		*fi = (field_info*) (node->data);
-	proto_tree_search_info	*sinfo = (proto_tree_search_info*) data;
-	header_field_info	*hfinfo;
+    GPtrArray *ptrs = proto_get_finfo_ptr_array(tree, id);
 
-	if (fi) { /* !fi == the top most container node which holds nothing */
-		/* Is this field one of the fields in the specified list
-		 * of fields? */
-		for (hfinfo = sinfo->target; hfinfo != NULL;
-		    hfinfo = hfinfo->same_name_next) {
-			if (fi->hfinfo == hfinfo) {
-				if (!sinfo->result.ptr_array) {
-					sinfo->result.ptr_array = g_ptr_array_new();
-				}
-				g_ptr_array_add(sinfo->result.ptr_array,
-						(gpointer)fi);
-				return FALSE; /* keep traversing */
-			}
-		}
-	}
-	return FALSE; /* keep traversing */
+    if (!ptrs) {
+        return FALSE;
+    }
+    else if (g_ptr_array_len(ptrs) > 0) {
+        return TRUE;
+    }
+    else {
+        return FALSE;
+    }
 }
 
-/* Return GPtrArray* of field_info pointers for all hfindex that appear in tree
- * (we assume that a field will only appear under its registered parent's subtree) */
+/* Return GPtrArray* of field_info pointers for all hfindex that appear in tree.
+ * This only works if the hfindex was "primed" before the dissection
+ * took place, as we just pass back the already-created GPtrArray*.
+ * The caller should *not* free the GPtrArray*; proto_tree_free_node()
+ * handles that. */
 GPtrArray*
 proto_get_finfo_ptr_array(proto_tree *tree, int id)
 {
-	proto_tree_search_info	sinfo;
-	header_field_info	*hfinfo;
-
-	hfinfo = proto_registrar_get_nth(id);
-
-	/* Find the first entry on the list of fields with the same
-	 * name as this field. */
-	while (hfinfo->same_name_prev != NULL)
-		hfinfo = hfinfo->same_name_prev;
-
-	sinfo.target		= hfinfo;
-	sinfo.result.ptr_array	= NULL;
-	sinfo.traverse_func	= get_finfo_ptr_array;
-	sinfo.halt_on_first_hit	= FALSE;
-
-	/* do a quicker check if target is a protocol */
-	if (proto_registrar_is_protocol(id) == TRUE) {
-		proto_find_protocol_multi(tree, get_finfo_ptr_array, &sinfo);
-	}
-	else {
-		/* Go through each protocol subtree. */
-		sinfo.traverse_func = get_finfo_ptr_array;
-		g_node_traverse((GNode*)tree, G_IN_ORDER, G_TRAVERSE_ALL, 2,
-						traverse_subtree_for_field, &sinfo);
-	}
-
-	return sinfo.result.ptr_array;
+    return g_hash_table_lookup(PTREE_DATA(tree)->interesting_hfids,
+            GINT_TO_POINTER(id));
 }
 
 
-
 typedef struct {
 	guint		offset;
 	field_info	*finfo;
@@ -2735,7 +2770,7 @@ typedef struct {
 static gboolean
 check_for_offset(GNode *node, gpointer data)
 {
-	field_info		*fi = node->data;
+	field_info          *fi = PITEM_FINFO(node);
 	offset_search_t		*offsearch = data;
 
 	/* !fi == the top most container node which holds nothing */
diff --git a/epan/proto.h b/epan/proto.h
index 57ed884705..6d86378ff8 100644
--- a/epan/proto.h
+++ b/epan/proto.h
@@ -1,7 +1,7 @@
 /* proto.h
  * Definitions for protocol display
  *
- * $Id: proto.h,v 1.24 2001/12/07 03:39:26 gram Exp $
+ * $Id: proto.h,v 1.25 2001/12/18 19:09:04 gram Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -42,9 +42,6 @@
 #include "tvbuff.h"
 #include "ftypes/ftypes.h"
 
-
-typedef GNode proto_tree;
-typedef GNode proto_item;
 struct value_string;
 
 #define ITEM_LABEL_LENGTH	240
@@ -107,7 +104,7 @@ typedef struct hf_register_info {
 } hf_register_info;
 
 
-/* Info stored in each proto_item GNode */
+/* Contains the field information for the proto_item. */
 typedef struct field_info {
 	header_field_info		*hfinfo;
 	gint				start;
@@ -119,6 +116,31 @@ typedef struct field_info {
 	gchar				*ds_name;  /* data source name */
 } field_info;
 
+/* One of these exists for the entire protocol tree. Each proto_node
+ * in the protocol tree points to the same copy. */
+typedef struct {
+    GHashTable  *interesting_hfids;
+    gboolean    visible;
+} tree_data_t;
+
+/* Each GNode (proto_tree, proto_item) points to one of
+ * these. */
+typedef struct {
+    field_info  *finfo;    
+    tree_data_t *tree_data;
+} proto_node;
+
+typedef GNode proto_tree;
+typedef GNode proto_item;
+
+/* Retrieve the proto_node from a GNode. */
+#define GNODE_PNODE(t)  ((proto_node*)((GNode*)(t))->data)
+
+/* Retrieve the field_info from a proto_item */
+#define PITEM_FINFO(t)  (GNODE_PNODE(t)->finfo)
+
+/* Retrieve the tree_data_t from a proto_tree */
+#define PTREE_DATA(t)   (GNODE_PNODE(t)->tree_data)
 
 /* Sets up memory used by proto routines. Called at program startup */
 extern void proto_init(const char *plugin_dir,
@@ -153,6 +175,10 @@ extern int proto_item_get_len(proto_item *ti);
 /* Creates new proto_tree root */
 extern proto_tree* proto_tree_create_root(void);
 
+/* Mark a field/protocol ID as "interesting". */    
+void
+proto_tree_prime_hfid(proto_tree *tree, int hfid);
+
 /* Clear memory for entry proto_tree. Clears proto_tree struct also. */
 extern void proto_tree_free(proto_tree *tree);
 
@@ -457,6 +483,9 @@ proto_tree_add_debug_text(proto_tree *tree, const char *format, ...);
 extern void
 proto_item_fill_label(field_info *fi, gchar *label_str);
 
+extern void
+proto_tree_set_visible(proto_tree *tree, gboolean visible);
+
 /* Returns number of items (protocols or header fields) registered. */
 extern int proto_registrar_n(void);