From a844abca43349739c36a4cdb7ea6f3bce560bd7f Mon Sep 17 00:00:00 2001
From: Rolf Eike Beer <eb@emlix.com>
Date: Thu, 8 Nov 2018 08:14:46 +0100
Subject: [PATCH] look for pthread_atfork() also in lib c_nonshared

Newer versions of glibc do not have pthread_nonshared anymore, instead the
symbol is in c_nonshared. This fixes a crash on start on those platforms
(namely with syslog-ng).

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
[ThomasDS: backport from https://github.com/buytenh/ivykis/pull/16, at this
moment not yet merged upstream.
See also:
- https://github.com/buytenh/ivykis/issues/15
- https://github.com/balabit/syslog-ng/issues/2263
]
Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>

---
 configure.ac | 2 ++
 src/pthr.h   | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/ivykis/configure.ac b/lib/ivykis/configure.ac
index e9b10c0..56440d1 100644
--- a/lib/ivykis/configure.ac
+++ b/lib/ivykis/configure.ac
@@ -88,6 +88,8 @@ esac
 # link in libpthread_nonshared.a if it is available.
 #
 AC_CHECK_LIB([pthread_nonshared], [pthread_atfork])
+# the lib is gone in glibc 2.28, things are now in c_nonshared
+AC_CHECK_LIB([c_nonshared], [pthread_atfork])
 
 # Checks for header files.
 AC_CHECK_HEADERS([process.h])
diff --git a/lib/ivykis/src/pthr.h b/lib/ivykis/src/pthr.h
index a41eaf3..32c1af2 100644
--- a/lib/ivykis/src/pthr.h
+++ b/lib/ivykis/src/pthr.h
@@ -42,7 +42,7 @@ static inline int pthreads_available(void)
  * symbol because that causes it to be undefined even if you link
  * libpthread_nonshared.a in explicitly.
  */
-#ifndef HAVE_LIBPTHREAD_NONSHARED
+#if !defined(HAVE_LIBPTHREAD_NONSHARED) && !defined(HAVE_LIBC_NONSHARED)
 #pragma weak pthread_atfork
 #endif