[2.26 COMMITTED] tst-ttyname: skip the test when /dev/ptmx is not available

[2.26 COMMITTED] tst-ttyname: skip the test when /dev/ptmx is not available

[Dmitry V. Levin]

* sysdeps/unix/sysv/linux/tst-ttyname.c (do_in_chroot_1): Skip the
test instead of failing in case of ENOENT returned by posix_openpt.

(cherry picked from commit d7ff3f11b64a28273285d341f795217bbf18ac9c)
---
 ChangeLog                             | 5 +++++
 sysdeps/unix/sysv/linux/tst-ttyname.c | 9 ++++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 929f846..f921251 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2018-01-08  Dmitry V. Levin  <ldv@altlinux.org>
+
+	* sysdeps/unix/sysv/linux/tst-ttyname.c (do_in_chroot_1): Skip the
+	test instead of failing in case of ENOENT returned by posix_openpt.
+
 2017-12-29  Aurelien Jarno  <aurelien@aurel32.net>
 
 	[BZ #22611]
diff --git a/sysdeps/unix/sysv/linux/tst-ttyname.c b/sysdeps/unix/sysv/linux/tst-ttyname.c
index 0fdf1a8..6848a6d 100644
--- a/sysdeps/unix/sysv/linux/tst-ttyname.c
+++ b/sysdeps/unix/sysv/linux/tst-ttyname.c
@@ -253,7 +253,14 @@ do_in_chroot_1 (int (*cb)(const char *, int))
   /* Open the PTS that we'll be testing on.  */
   int master;
   char *slavename;
-  VERIFY ((master = posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK)) >= 0);
+  master = posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK);
+  if (master < 0)
+    {
+      if (errno == ENOENT)
+	FAIL_UNSUPPORTED ("posix_openpt: %m");
+      else
+	FAIL_EXIT1 ("posix_openpt: %m");
+    }
   VERIFY ((slavename = ptsname (master)));
   VERIFY (unlockpt (master) == 0);
   if (strncmp (slavename, "/dev/pts/", 9) != 0)
-- 
ldv