Improve support for single-character fields and filter expressions.

Add an FT_CHAR type, which is like FT_UINT8 except that the value is
displayed as a C-style character constant.

Allow use of C-style character constants in filter expressions; they can
be used in comparisons with all integral types, and in "contains"
operators.

Use that type for some fields that appear (based on the way they're
displayed, or on the use of C-style character constants in their
value_string tables) to be 1-byte characters rather than 8-bit numbers.

Change-Id: I39a9f0dda0bd7f4fa02a9ca8373216206f4d7135
Reviewed-on: https://code.wireshark.org/review/17787
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 48 insertions, 292 deletions

diff --git a/epan/dissectors/packet-ouch.c b/epan/dissectors/packet-ouch.c
index 5d6e1dc298..c2eb1641b6 100644
--- a/epan/dissectors/packet-ouch.c
+++ b/epan/dissectors/packet-ouch.c
@@ -350,201 +350,6 @@ ouch_tree_add_timestamp(
     proto_tree_add_string(tree, hf, tvb, offset, 8, buf);
 }
 
-static void
-packet_type_format(
-    gchar *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, pkt_type_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for BBO weight indicator code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_bbo_weight_indicator(
-    gchar *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value,
-                                ouch_bbo_weight_indicator_val,
-                                "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for broken trade reason code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_broken_trade_reason(
-    gchar *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value,
-                                ouch_broken_trade_reason_val,
-                                "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for buy/sell indicator code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_buy_sell_indicator(
-    gchar *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_buy_sell_indicator_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for cancel reason code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_cancel_reason(
-    gchar *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_cancel_reason_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the capacity code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_capacity(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_capacity_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the cross type code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_cross_type(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_cross_type_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the customer type code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_customer_type(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_customer_type_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the display code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_display(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_display_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the system event code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_event_code(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_event_code_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the ISO eligibility code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_iso_eligibility(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_iso_eligibility_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for the liquidity flag code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_liquidity_flag(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_liquidity_flag_val, "Unknown"),
-               value);
-}
-
-/** BASE_CUSTOM formatter for order state code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_order_state(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_order_state_val, "Unknown"),
-               value);
-}
-
 /** BASE_CUSTOM formatter for prices
  *
  * OUCH prices are integers, with four implicit decimal places.  So we
@@ -563,23 +368,6 @@ format_price(
     }
 }
 
-/** BASE_CUSTOM formatter for price correction reason code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_price_correction_reason(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value,
-                                ouch_price_correction_reason_val,
-                                "Unknown"),
-               value);
-}
-
 /** BASE_CUSTOM formatter for reference price type code
  *
  * Displays the code value as a character, not its ASCII value, as
@@ -597,21 +385,6 @@ format_reference_price_type(
                value);
 }
 
-/** BASE_CUSTOM formatter for the reject reason code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_reject_reason(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value, ouch_reject_reason_val, "Unknown"),
-               value);
-}
-
 /** BASE_CUSTOM formatter for the Time In Force (TIF) code
  *
  * There are three reserved values for the TIF: 0, 99998 and 99999.
@@ -653,23 +426,6 @@ format_tif(
     }
 }
 
-/** BASE_CUSTOM formatter for the trade correction reason code
- *
- * Displays the code value as a character, not its ASCII value, as
- * would be done by BASE_DEC and friends. */
-static void
-format_trade_correction_reason(
-    char *buf,
-    guint32 value)
-{
-    g_snprintf(buf, ITEM_LABEL_LENGTH,
-               "%s (%c)",
-               val_to_str_const(value,
-                                ouch_trade_correction_reason_val,
-                                "Unknown"),
-               value);
-}
-
 
 static int
 dissect_ouch(
@@ -729,7 +485,7 @@ dissect_ouch(
 
         /* Packet type (using the cooked value). */
         proto_tree_add_item(ouch_tree, hf_ouch_packet_type,
-                                  tvb, offset, 1, ENC_NA);
+                                  tvb, offset, 1, ENC_ASCII|ENC_NA);
         offset += 1;
 
         switch (pkt_type) {
@@ -743,7 +499,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_buy_sell_indicator,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -779,19 +535,19 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_display,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_capacity,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_iso_eligible,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -803,14 +559,14 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_cross_type,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             if (reported_len >= 49) { /* Added in 4.1 */
                 proto_tree_add_item(ouch_tree,
                                     hf_ouch_customer_type,
                                     tvb, offset, 1,
-                                    ENC_BIG_ENDIAN);
+                                    ENC_ASCII|ENC_NA);
                 offset += 1;
             }
             break;
@@ -866,7 +622,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_display,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -878,13 +634,13 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_capacity,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_iso_eligible,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -896,20 +652,20 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_cross_type,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_order_state,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             if (reported_len >= 66) { /* Added in 4.2 */
                 proto_tree_add_item(ouch_tree,
                                     hf_ouch_bbo_weight_indicator,
                                     tvb, offset, 1,
-                                    ENC_BIG_ENDIAN);
+                                    ENC_ASCII|ENC_NA);
                 offset += 1;
             }
             break;
@@ -948,13 +704,13 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_display,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_iso_eligible,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1007,7 +763,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_event_code,
                                 tvb, offset, 1,
-                                ENC_ASCII);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1062,7 +818,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_display,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1074,13 +830,13 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_capacity,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_iso_eligible,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1092,13 +848,13 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_cross_type,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_order_state,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1137,7 +893,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_cancel_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1162,7 +918,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_cancel_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1180,7 +936,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_liquidity_flag,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1211,7 +967,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_liquidity_flag,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1242,7 +998,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_broken_trade_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1273,7 +1029,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_liquidity_flag,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1285,7 +1041,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_trade_correction_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1316,7 +1072,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_liquidity_flag,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1365,7 +1121,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_price_correction_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1384,7 +1140,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_reject_reason,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
             break;
 
@@ -1435,7 +1191,7 @@ dissect_ouch(
             proto_tree_add_item(ouch_tree,
                                 hf_ouch_display,
                                 tvb, offset, 1,
-                                ENC_BIG_ENDIAN);
+                                ENC_ASCII|ENC_NA);
             offset += 1;
 
             proto_tree_add_item(ouch_tree,
@@ -1638,37 +1394,37 @@ proto_register_ouch(void)
 
         { &hf_ouch_bbo_weight_indicator,
           { "BBO Weight Indicator", "ouch.bbo_weight_indicator",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_bbo_weight_indicator), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_bbo_weight_indicator_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_broken_trade_reason,
           { "Broken Trade Reason", "ouch.broken_trade_reason",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_broken_trade_reason), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_broken_trade_reason_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_buy_sell_indicator,
           { "Buy/Sell Indicator", "ouch.buy_sell_indicator",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_buy_sell_indicator), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_buy_sell_indicator_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_cancel_reason,
           { "Cancel Reason", "ouch.cancel_reason",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_cancel_reason), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_cancel_reason_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_capacity,
           { "Capacity", "ouch.capacity",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_capacity), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_capacity_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_cross_type,
           { "Cross Type", "ouch.cross_type",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_cross_type), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_cross_type_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_customer_type,
           { "Customer Type", "ouch.customer_type",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_customer_type), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_customer_type_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_decrement_shares,
@@ -1678,12 +1434,12 @@ proto_register_ouch(void)
 
         { &hf_ouch_display,
           { "Display", "ouch.display",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_display), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_display_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_event_code,
           { "Event Code", "ouch.event_code",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_event_code), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_event_code_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_executed_shares,
@@ -1708,12 +1464,12 @@ proto_register_ouch(void)
 
         { &hf_ouch_iso_eligible,
           { "Intermarket Sweep Eligibility", "ouch.iso_eligible",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_iso_eligibility), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_iso_eligibility_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_liquidity_flag,
           { "Liquidity Flag", "ouch.liquidity_flag",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_liquidity_flag), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_liquidity_flag_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_match_number,
@@ -1743,7 +1499,7 @@ proto_register_ouch(void)
 
         { &hf_ouch_order_state,
           { "Order State", "ouch.order_state",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_order_state), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_order_state_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_order_token,
@@ -1753,7 +1509,7 @@ proto_register_ouch(void)
 
         { &hf_ouch_packet_type,
           { "Packet Type", "ouch.packet_type",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(packet_type_format), 0x0,
+            FT_CHAR, BASE_HEX, VALS(pkt_type_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_previous_order_token,
@@ -1768,7 +1524,7 @@ proto_register_ouch(void)
 
         { &hf_ouch_price_correction_reason,
           { "Price Correction Reason", "ouch.price_correction_reason",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_price_correction_reason), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_price_correction_reason_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_quantity_prevented_from_trading,
@@ -1789,7 +1545,7 @@ proto_register_ouch(void)
 
         { &hf_ouch_reject_reason,
           { "Reject Reason", "ouch.reject_reason",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_reject_reason), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_reject_reason_val), 0x0,
             NULL, HFILL }},
 
         { &hf_ouch_replacement_order_token,
@@ -1819,7 +1575,7 @@ proto_register_ouch(void)
 
         { &hf_ouch_trade_correction_reason,
           { "Trade Correction Reason", "ouch.trade_correction_reason",
-            FT_UINT8, BASE_CUSTOM, CF_FUNC(format_trade_correction_reason), 0x0,
+            FT_CHAR, BASE_HEX, VALS(ouch_trade_correction_reason_val), 0x0,
             NULL, HFILL }}
     };