ndppd-0001-Fixes-strerror_r-GNU-XSI.patch

From 1f610129b475b417509b251e022ad46d2210ff50 Mon Sep 17 00:00:00 2001
From: Rafael Cossovan <navossoc@gmail.com>
Date: Tue, 3 Apr 2018 17:04:35 -0300
Subject: [PATCH 2/3] Fixes strerror_r GNU/XSI issue #40.
 http://www.zverovich.net/2015/03/13/reliable-detection-of-strerror-variants.html

---
 src/logger.cc | 14 ++++++++++++-
 src/logger.h  |  3 +++
 2 files changed, 15 insertions(+), 1 deletions(-)

diff --git a/src/logger.cc b/src/logger.cc
index 6ddbea9..6ccb2a0 100644
--- a/src/logger.cc
+++ b/src/logger.cc
@@ -84,13 +84,7 @@ std::string logger::err()
 {
     char buf[2048];

-#if (_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && ! _GNU_SOURCE
-    if (strerror_r(errno, buf, sizeof(buf))
-        return "Unknown error";
-    return buf;
-#else
-    return strerror_r(errno, buf, sizeof(buf));
-#endif
+    return strerror_r_wrapper(strerror_r(errno, buf, sizeof(buf)), buf);
 }

 logger logger::error()
@@ -221,4 +221,16 @@ 
     return false;
 }

+// XSI-compliant: int
+std::string logger::strerror_r_wrapper(int, char* s)
+{
+    return s;
+}
+
+// GNU-specific: char *
+std::string logger::strerror_r_wrapper(char* s, char*)
+{
+    return s;
+}
+
 NDPPD_NS_END
diff --git a/src/logger.h b/src/logger.h
index 7d3d7db..0446595 100644
--- a/src/logger.h
+++ b/src/logger.h
@@ -91,6 +91,9 @@ class logger {
 
     static int _max_pri;
 
+    // helpers for strerror_r
+    static std::string strerror_r_wrapper(int, char* s);
+    static std::string strerror_r_wrapper(char* s, char*);
 
 };