tests: ipcpipeline: provide pipe2() on systems that don't have it

https://bugzilla.gnome.org/show_bug.cgi?id=786763

configure.ac

@@ -171,7 +171,7 @@ dnl *** checks for structures ***
 dnl *** checks for compiler characteristics ***
 
 dnl *** checks for library functions ***
-AC_CHECK_FUNCS([gmtime_r])
+AC_CHECK_FUNCS([gmtime_r pipe2])
 
 dnl *** checks for headers ***
 AC_CHECK_HEADERS([sys/utsname.h])

meson.build

@@ -195,6 +195,7 @@ check_functions = [
 # check token HAVE_ORC
 # check token HAVE_OSX
 # check token HAVE_OSX_VIDEO
+  ['HAVE_PIPE2', 'pipe2'],
 # check token HAVE_PNG
 # check token HAVE_PVR
 # check token HAVE_QUICKTIME

tests/check/pipelines/ipcpipeline.c

@@ -22,6 +22,10 @@
  * Boston, MA 02110-1301, USA.
  */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #define _GNU_SOURCE             /* See feature_test_macros(7) */
 #include <unistd.h>
 #include <stdio.h>
@@ -33,6 +37,25 @@
 #include <gst/check/gstcheck.h>
 #include <string.h>
 
+#ifndef HAVE_PIPE2
+static int
+pipe2 (int pipedes[2], int flags)
+{
+  int ret = pipe (pipedes);
+  if (ret < 0)
+    return ret;
+  if (flags != 0) {
+    ret = fcntl (pipedes[0], F_SETFL, flags);
+    if (ret < 0)
+      return ret;
+    ret = fcntl (pipedes[1], F_SETFL, flags);
+    if (ret < 0)
+      return ret;
+  }
+  return 0;
+}
+#endif
+
 /* This enum contains flags that are used to configure the setup that
  * test_base() will do internally */
 typedef enum