From: Peter Maydell <pmaydell@chiark.greenend.org.uk>
Date: Mon, 20 Dec 2010 21:13:32 +0000 (+0000)
Subject: Fix crash if fnext/fprev are given an empty folder list
X-Git-Tag: mmh-start~8
X-Git-Url: http://git.marmaro.de/?p=mmh;a=commitdiff_plain;h=9530ace10a49d62c80c95914601fa9246099501b

Fix crash if fnext/fprev are given an empty folder list

Add a check for a NULL pointer, which stops fnext/fprev
from segfaulting if given an empty folder list (for example
via 'fnext -folders emptyfile').

Signed-off-by: Peter Maydell <pmaydell@chiark.greenend.org.uk>
---

diff --git a/uip/new.c b/uip/new.c
index 41d2ebf..254950b 100644
--- a/uip/new.c
+++ b/uip/new.c
@@ -308,7 +308,10 @@ doit(char *cur, char *folders, char *sequences[])
 		  folders, sequences);
 
     if (run_mode == FNEXT || run_mode == FPREV) {
-	if (first->n_next == NULL) {
+	if (first == NULL) {
+	    /* No folders at all... */
+	    return NULL;
+	} else if (first->n_next == NULL) {
 	    /* We have only one node; any desired messages in it? */
 	    if (first->n_field == NULL) {
 		return NULL;