From 950c4ed9c6bb9c31d540c9f0aff436538fe3a045 Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Tue, 23 Sep 2014 00:45:12 +0100
Subject: [PATCH] Check return value of fseek for errors.

---
 src/websockets.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/websockets.c b/src/websockets.c
index 5c0741cc..676d527e 100644
--- a/src/websockets.c
+++ b/src/websockets.c
@@ -475,7 +475,11 @@ static int callback_http(struct libwebsocket_context *context,
 					}
 					wlen = libwebsocket_write(wsi, buf, buflen, LWS_WRITE_HTTP);
 					if(wlen < buflen){
-						fseek(u->fptr, buflen-wlen, SEEK_CUR);
+						if(fseek(u->fptr, buflen-wlen, SEEK_CUR) < 0){
+							fclose(u->fptr);
+							u->fptr = NULL;
+							return -1;
+						}
 					}else{
 						if(buflen < sizeof(buf)){
 							fclose(u->fptr);