Convert COLOR_DEFAULT constant to -1.

Previously, "mono" assigned -1 to fg/bg to indicate "unset" values.

NCurses uses -1 to indicate "default" color (when supported), but
COLOR_DEFAULT was assigned the value -2 and swapped at the last
moment.  While it worked, I personally found this confusing.

To make the logic clearer, create a COLOR_UNSET constant with value
-2, and switch COLOR_DEFAULT to -1.  Then remove the last-minute
translation when allocating the color.

Change the "not set" initialization and testing to use COLOR_UNSET for
clarity.

Because map_getvaluebyname() returns -1 for a missing value,
create a new lookup function that returns the matching mapping_t or
NULL if not found.

1 files changed, 12 insertions, 3 deletions

diff --git a/init.c b/init.c
index 7a0f1353..64571ce4 100644
--- a/init.c
+++ b/init.c
@@ -3557,14 +3557,23 @@ const char *mutt_getnamebyvalue (int val, const struct mapping_t *map)
   return NULL;
 }
 
-int mutt_getvaluebyname (const char *name, const struct mapping_t *map)
+const struct mapping_t *mutt_get_mapentry_by_name (const char *name,
+                                                  const struct mapping_t *map)
 {
   int i;
 
   for (i = 0; map[i].name; i++)
     if (ascii_strcasecmp (map[i].name, name) == 0)
-      return (map[i].value);
-  return (-1);
+      return &map[i];
+  return NULL;
+}
+
+int mutt_getvaluebyname (const char *name, const struct mapping_t *map)
+{
+  const struct mapping_t *entry = mutt_get_mapentry_by_name (name, map);
+  if (entry)
+    return entry->value;
+  return -1;
 }
 
 #ifdef DEBUG