[ruamoko] Add support for PL_KeyAtIndex

I'd forgotten to wrap the function when I added it, but didn't need it
until now.

libs/ruamoko/rua_plist.c

@@ -322,6 +322,18 @@ bi_PL_D_NumKeys (progs_t *pr, void *_res)
 	R_INT (pr) = PL_D_NumKeys (plist->plitem);
 }
 
+static void
+bi_PL_KeyAtIndex (progs_t *pr, void *_res)
+{
+	plist_resources_t *res = _res;
+	int         handle = P_INT (pr, 0);
+	int         index = P_INT (pr, 1);
+	bi_plist_t *plist = get_plist (pr, res, __FUNCTION__, handle);
+	const char *key = PL_KeyAtIndex (plist->plitem, index);
+
+	RETURN_STRING (pr, key);
+}
+
 static void
 bi_PL_D_AddObject (progs_t *pr, void *_res)
 {
@@ -474,6 +486,7 @@ static builtin_t builtins[] = {
 	bi(PL_ObjectAtIndex,         2, p(ptr), p(int)),
 	bi(PL_D_AllKeys,             1, p(ptr)),
 	bi(PL_D_NumKeys,             1, p(ptr)),
+	bi(PL_KeyAtIndex,            2, p(ptr), p(int)),
 	bi(PL_D_AddObject,           3, p(ptr), p(string), p(ptr)),
 	bi(PL_A_AddObject,           2, p(ptr), p(ptr)),
 	bi(PL_A_NumObjects,          1, p(ptr)),

ruamoko/include/PropertyList.h

@@ -11,6 +11,7 @@
 - (int) numKeys;
 - (PLItem *) getObjectForKey:(string) key;
 - (PLItem *) allKeys;
+- (string) keyAtIndex:(int) index;
 - addKey:(string) key value:(PLItem *) value;
 @end
 

ruamoko/include/plist.h

@@ -16,6 +16,7 @@ typedef enum {QFDictionary, QFArray, QFBinary, QFString} pltype_t;	// possible t
 @extern plitem_t *PL_RemoveObjectForKey (plitem_t *item, string key);
 @extern plitem_t *PL_ObjectAtIndex (plitem_t *item, int index);
 @extern plitem_t *PL_D_AllKeys (plitem_t *item);
+@extern string PL_KeyAtIndex (plitem_t *item, int index);
 @extern int PL_D_NumKeys (plitem_t *item);
 @extern int PL_D_AddObject (plitem_t *dict, string key, plitem_t *value);
 @extern int PL_A_AddObject (plitem_t *array_item, plitem_t *item);

ruamoko/lib/PropertyList.r

@@ -128,6 +128,11 @@
 	return [[PLItem itemClass: PL_D_AllKeys (item)] autorelease];
 }
 
+- (string) keyAtIndex:(int) index
+{
+	return PL_KeyAtIndex (item, index);
+}
+
 - addKey:(string) key value:(PLItem *) value
 {
 	if (!value.own) {

ruamoko/lib/plist.r

@@ -10,6 +10,7 @@ plitem_t *PL_ObjectForKey (plitem_t *item, string key) = #0;
 plitem_t *PL_RemoveObjectForKey (plitem_t *item, string key) = #0;
 plitem_t *PL_ObjectAtIndex (plitem_t *item, int index) = #0;
 plitem_t *PL_D_AllKeys (plitem_t *item) = #0;
+string PL_KeyAtIndex (plitem_t *item, int index) = #0;
 int PL_D_NumKeys (plitem_t *item) = #0;
 int PL_D_AddObject (plitem_t *dict, string key, plitem_t *value) = #0;
 int PL_A_AddObject (plitem_t *array_item, plitem_t *item) = #0;