From: mlichvar <mlichvar>
Date: Fri, 15 Sep 2006 13:25:19 +0000 (+0000)
Subject: - fix a crash in checkboxtree.c where pressing pgup/pgdown
X-Git-Tag: r0-52-3~17
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=21f6373f024eadcb9818b6e1a2961c9cda538241;p=thirdparty%2Fnewt.git

- fix a crash in checkboxtree.c where pressing pgup/pgdown
  on a checkboxtree with less items than its height would
  cause segmentation violation (#165347)
---

diff --git a/checkboxtree.c b/checkboxtree.c
index f862db6..262e1d2 100644
--- a/checkboxtree.c
+++ b/checkboxtree.c
@@ -536,6 +536,18 @@ static void ctDestroy(newtComponent co) {
     free(co);
 }
 
+static void ctEnsureLimits( struct CheckboxTree *ct ) {
+    struct items **listEnd = ct->flatList + ct->flatCount - 1;
+    if (ct->firstItem < ct->flatList)
+        ct->firstItem = ct->flatList;
+    if (ct->currItem < ct->flatList)
+        ct->currItem = ct->flatList;
+    if (ct->firstItem > listEnd) {
+        ct->firstItem = listEnd;
+        ct->currItem = listEnd;
+    }
+}
+
 struct eventResult ctEvent(newtComponent co, struct event ev) {
     struct CheckboxTree * ct = co->data;
     struct eventResult er;
@@ -647,6 +659,7 @@ struct eventResult ctEvent(newtComponent co, struct event ev) {
 		ct->currItem -= co->height;
 		ct->firstItem -= co->height;
 	    }
+	    ctEnsureLimits( ct );
 
 	    ctDraw(co);
 	    if(co->callback) co->callback(co, co->callbackData);
@@ -663,6 +676,7 @@ struct eventResult ctEvent(newtComponent co, struct event ev) {
 	    	ct->currItem += co->height;
 		ct->firstItem += co->height;
 	    }
+	    ctEnsureLimits( ct );
 
 	    ctDraw(co);
 	    if(co->callback) co->callback(co, co->callbackData);