Rename BASE_STRUCTURE_RESET to BASE_DISPLAY_E_MASK, to clarify that it's

a mask to select the base_display_e value from a display field in a
header_field_info structure.

Never select that value by masking out the BASE_RANGE_STRING flag bit,
as that won't continue to work if more flag bits, or other bitfields,
are added.  Instead, mask with BASE_DISPLAY_E_MASK.

Note that the base_display_e value and BASE_RANGE_STRING flag are only
for integral field types, and clarify what BASE_DISPLAY_E_MASK is.

Give at least one of the reasons why hiding protocol fields is not
considered a good idea.

svn path=/trunk/; revision=31249

3 files changed, 31 insertions, 25 deletions

diff --git a/epan/proto.c b/epan/proto.c
index af01ce2959..6256435af8 100644
--- a/epan/proto.c
+++ b/epan/proto.c
@@ -4815,9 +4815,8 @@ hfinfo_uint_vals_format(header_field_info *hfinfo)
 {
 	const char *format = NULL;
 
-	/* bit operation to reset the potential BASE_RANGE_STRING (or others in
-	 * the future?) */
-	switch(hfinfo->display & BASE_STRUCTURE_RESET) {
+	/* Get the underlying BASE_ value */
+	switch(hfinfo->display & BASE_DISPLAY_E_MASK) {
 		case BASE_NONE:
 			format = "%s: %s";
 			break;
@@ -5028,9 +5027,8 @@ hfinfo_int_vals_format(header_field_info *hfinfo)
 {
 	const char *format = NULL;
 
-	/* bit operation to reset the potential BASE_RANGE_STRING (or others in
-	 * the future?)*/
-	switch(hfinfo->display & BASE_STRUCTURE_RESET) {
+	/* Get the underlying BASE_ value */
+	switch(hfinfo->display & BASE_DISPLAY_E_MASK) {
 		case BASE_NONE:
 			format = "%s: %s";
 			break;
@@ -5600,7 +5598,7 @@ proto_registrar_dump_values(void)
 			range = NULL;
 			tfs   = NULL;
 
-			if ((hfinfo->display & BASE_STRUCTURE_RESET) != BASE_CUSTOM &&
+			if ((hfinfo->display & BASE_DISPLAY_E_MASK) != BASE_CUSTOM &&
 				(hfinfo->type == FT_UINT8 ||
 				hfinfo->type == FT_UINT16 ||
 				hfinfo->type == FT_UINT24 ||
@@ -5648,7 +5646,7 @@ proto_registrar_dump_values(void)
 				vi = 0;
 				while (range[vi].strptr) {
 					/* Print in the proper base */
-					if ((hfinfo->display & BASE_STRUCTURE_RESET) == BASE_HEX) {
+					if ((hfinfo->display & BASE_DISPLAY_E_MASK) == BASE_HEX) {
 						printf("R\t%s\t0x%x\t0x%x\t%s\n",
 								hfinfo->abbrev,
 								range[vi].value_min,
@@ -5778,7 +5776,7 @@ proto_registrar_dump_fields(int format)
 					hfinfo->type == FT_INT64) {
 
 
-					switch(hfinfo->display & BASE_STRUCTURE_RESET) {
+					switch(hfinfo->display & BASE_DISPLAY_E_MASK) {
 						case BASE_NONE:
 							base_name = "BASE_NONE";
 							break;
@@ -5850,8 +5848,8 @@ hfinfo_numeric_format(header_field_info *hfinfo)
 		 */
 		format = "%s == %u";
 	} else {
-		/* Pick the proper format string, ignoring BASE_RANGE_STRING flag */
-		switch(hfinfo->display & ~BASE_RANGE_STRING) {
+		/* Get the underlying BASE_ value */
+		switch(hfinfo->display & BASE_DISPLAY_E_MASK) {
 			case BASE_DEC:
 			case BASE_DEC_HEX:
 			case BASE_OCT: /* I'm lazy */
@@ -5937,7 +5935,7 @@ construct_match_selected_string(field_info *finfo, epan_dissect_t *edt,
 	DISSECTOR_ASSERT(hfinfo);
 	abbrev_len = (int) strlen(hfinfo->abbrev);
 
-	if (hfinfo->strings && (hfinfo->display & BASE_STRUCTURE_RESET) == BASE_NONE) {
+	if (hfinfo->strings && (hfinfo->display & BASE_DISPLAY_E_MASK) == BASE_NONE) {
 		const gchar *str = NULL;
 
 		switch(hfinfo->type) {
diff --git a/epan/proto.h b/epan/proto.h
index 083953b40f..c0e146157d 100644
--- a/epan/proto.h
+++ b/epan/proto.h
@@ -140,15 +140,15 @@ typedef struct _protocol protocol_t;
     ep_strdup_printf("%s:%u: failed assertion \"%s\"", \
      file, lineno, __DISSECTOR_ASSERT_STRINGIFY(expression))))
 
-/* BASE_STRUCTURE_RESET constant is used in proto.c to reset the bits
- * identifying special structures used in translation of value for display.
- * Its value means that we may have at most 16 base_display_e values */
-#define BASE_STRUCTURE_RESET 0x0F
-/* Following constants have to be ORed with a base_display_e when dissector
- * want to use specials MACROs (for the moment, only RVALS) for a
- * header_field_info */
-#define BASE_RANGE_STRING 0x10
-/** radix for decimal values, used in header_field_info.display */
+/* Values for header_field_info.display */
+
+/* For integral types, the display format is a base_display_e value
+ * possibly ORed with BASE_RANGE_STRING. */
+
+/* BASE_DISPLAY_E_MASK selects the base_display_e value.  Its current
+ * value means that we may have at most 16 base_display_e values. */
+#define BASE_DISPLAY_E_MASK 0x0F
+
 typedef enum {
 	BASE_NONE,	/**< none */
 	BASE_DEC,	/**< decimal */
@@ -159,14 +159,20 @@ typedef enum {
 	BASE_CUSTOM	/**< call custom routine (in ->strings) to format */
 } base_display_e;
 
+/* Following constants have to be ORed with a base_display_e when dissector
+ * want to use specials MACROs (for the moment, only RVALS) for a
+ * header_field_info */
+#define BASE_RANGE_STRING 0x10
+
+/* BASE_ values that cause the field value to be displayed twice */
+#define IS_BASE_DUAL(b) ((b)==BASE_DEC_HEX||(b)==BASE_HEX_DEC)
+
 typedef enum {
     HF_REF_TYPE_NONE,       /**< Field is not referenced */
     HF_REF_TYPE_INDIRECT,   /**< Field is indirectly referenced (only applicable for FT_PROTOCOL) via. its child */
     HF_REF_TYPE_DIRECT      /**< Field is directly referenced */
 } hf_ref_type;
 
-#define IS_BASE_DUAL(b) ((b)==BASE_DEC_HEX||(b)==BASE_HEX_DEC)
-
 /** information describing a header field */
 typedef struct _header_field_info header_field_info;
 
@@ -237,7 +243,9 @@ typedef struct field_info {
 
 /** The protocol field should not be shown in the tree (it's used for filtering only),
  * used in field_info.flags. */
-/* HIDING PROTOCOL FIELDS IS DEPRECATED, IT'S CONSIDERED TO BE BAD GUI DESIGN! */
+/* HIDING PROTOCOL FIELDS IS DEPRECATED, IT'S CONSIDERED TO BE BAD GUI DESIGN!
+   A user cannot tell by looking at the packet detail that the field exists
+   and that they can filter on its value. */
 #define FI_HIDDEN		0x00000001
 /** The protocol field should be displayed as "generated by Wireshark",
  * used in field_info.flags. */
diff --git a/gtk/dfilter_expr_dlg.c b/gtk/dfilter_expr_dlg.c
index ae030a2f79..6b6c970e01 100644
--- a/gtk/dfilter_expr_dlg.c
+++ b/gtk/dfilter_expr_dlg.c
@@ -558,7 +558,7 @@ value_list_sel_cb(GtkTreeSelection *sel, gpointer value_entry_arg)
          * selected item, and display it in the base for this
          * field.
          */
-        switch ((hfinfo->display) & BASE_STRUCTURE_RESET) {
+        switch ((hfinfo->display) & BASE_DISPLAY_E_MASK) {
 
         case BASE_NONE:
         case BASE_DEC: