From dc6031379ee6a09718b065387fbd3d6e5429a0d9 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Fri, 5 Oct 2018 22:43:34 +0100
Subject: [PATCH] configure.ac: memshr_create: Detect and use from <sys/mman.h>

Recent glibc versions do have a wrapper for this function.  It is available via
<sys/mman.h>.  So:
  * Add <sys/mman.h> to the list of header checks.
  * Add a conditional include of <sys/mman.h> to the configure test
    for memshr_create, so that it will pass if the function is there.
  * Add the same conditional include to missing.h, so that we
    get it declared when we build.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 configure.ac        | 4 ++++
 src/basic/missing.h | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/configure.ac b/configure.ac
index c0ad243d2..9ec3390ff 100644
--- a/configure.ac
+++ b/configure.ac
@@ -358,6 +358,7 @@ AM_CONDITIONAL([HAVE_PYTHON], [test "x$have_python" = "xyes"])
 # ------------------------------------------------------------------------------
 
 AC_CHECK_HEADERS([sys/capability.h], [], [AC_MSG_ERROR([*** POSIX caps headers not found])])
+AC_CHECK_HEADERS([sys/mman.h], [], [])
 AC_CHECK_HEADERS([linux/memfd.h], [], [])
 AC_CHECK_HEADERS([linux/vm_sockets.h], [], [], [#include <sys/socket.h>])
 
@@ -399,6 +400,9 @@ AC_CHECK_DECLS([
 #include <sched.h>
 #include <string.h>
 #include <linux/loop.h>
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
 ]])
 
 AC_CHECK_DECLS([getrandom],
diff --git a/src/basic/missing.h b/src/basic/missing.h
index c62c2db1c..e8508e770 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -55,6 +55,10 @@
 #include <linux/btrfs.h>
 #endif
 
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
 #ifdef HAVE_LINUX_VM_SOCKETS_H
 #include <linux/vm_sockets.h>
 #else
-- 
2.30.2