From: Marcel Raad <Marcel.Raad@teamviewer.com>
Date: Sat, 25 May 2019 17:24:13 +0000 (+0200)
Subject: examples/fopen: fix comparison
X-Git-Tag: curl-7_65_2~110
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=992083b1abe2f19947abe1d5ba01c488458f6e66;p=thirdparty%2Fcurl.git

examples/fopen: fix comparison

As want is size_t, (file->buffer_pos - want) is unsigned, so checking
if it's less than zero makes no sense.
Check if file->buffer_pos is less than want instead to avoid the
unsigned integer wraparound.

Closes https://github.com/curl/curl/pull/3975
---

diff --git a/docs/examples/fopen.c b/docs/examples/fopen.c
index f1706fbe63..7151adddec 100644
--- a/docs/examples/fopen.c
+++ b/docs/examples/fopen.c
@@ -211,7 +211,7 @@ static int fill_buffer(URL_FILE *file, size_t want)
 static int use_buffer(URL_FILE *file, size_t want)
 {
   /* sort out buffer */
-  if((file->buffer_pos - want) <= 0) {
+  if(file->buffer_pos <= want) {
     /* ditch buffer - write will recreate */
     free(file->buffer);
     file->buffer = NULL;