From 58d74230d5fd6893d63fdfc5da8da4f68c7270be Mon Sep 17 00:00:00 2001
From: Peter Barker <pbarker@barker.dropbear.id.au>
Date: Tue, 14 Feb 2017 13:25:32 +1100
Subject: [PATCH] DataFlash: correct error detection for asprintf

---
 libraries/DataFlash/DataFlash_File.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libraries/DataFlash/DataFlash_File.cpp b/libraries/DataFlash/DataFlash_File.cpp
index 90a981ed72..c892040fd0 100644
--- a/libraries/DataFlash/DataFlash_File.cpp
+++ b/libraries/DataFlash/DataFlash_File.cpp
@@ -422,7 +422,7 @@ bool DataFlash_File::NeedPrep()
 char *DataFlash_File::_log_file_name(const uint16_t log_num) const
 {
     char *buf = nullptr;
-    if (asprintf(&buf, "%s/%u.BIN", _log_directory, (unsigned)log_num) == 0) {
+    if (asprintf(&buf, "%s/%u.BIN", _log_directory, (unsigned)log_num) == -1) {
         return nullptr;
     }
     return buf;
@@ -435,7 +435,7 @@ char *DataFlash_File::_log_file_name(const uint16_t log_num) const
 char *DataFlash_File::_lastlog_file_name(void) const
 {
     char *buf = nullptr;
-    if (asprintf(&buf, "%s/LASTLOG.TXT", _log_directory) == 0) {
+    if (asprintf(&buf, "%s/LASTLOG.TXT", _log_directory) == -1) {
         return nullptr;
     }
     return buf;