Port close-on-exec pty creation to FreeBSD 9.1-RELEASE.

* configure.ac (PTY_OPEN): If posix_openpt with O_CLOEXEC fails
and reports EINVAL, try it again without O_CLOEXEC.  This should
port PTY_OPEN to FreeBSD 9, which stupidly rejects O_CLOEXEC.
What were they thinking?

Fixes: debbugs:15129

2 files changed, 9 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index a86343b0953..161069800a4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2013-08-21  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Port close-on-exec pty creation to FreeBSD 9.1-RELEASE (Bug#15129).
+        * configure.ac (PTY_OPEN): If posix_openpt with O_CLOEXEC fails
+        and reports EINVAL, try it again without O_CLOEXEC.  This should
+        port PTY_OPEN to FreeBSD 9, which stupidly rejects O_CLOEXEC.
+        What were they thinking?
+
 2013-08-20  Paul Eggert  <eggert@cs.ucla.edu>
 
         * Makefile.in (distclean, bootstrap-clean, maintainer-clean):
diff --git a/configure.ac b/configure.ac
index 980c36f75c7..793267b6ccb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3994,7 +3994,7 @@ case $opsys in
       AC_DEFINE(PTY_TTY_NAME_SPRINTF, [{ char *ptyname = 0; sigset_t blocked; sigemptyset (&blocked); sigaddset (&blocked, SIGCHLD); pthread_sigmask (SIG_BLOCK, &blocked, 0); if (grantpt (fd) != -1 && unlockpt (fd) != -1) ptyname = ptsname(fd); pthread_sigmask (SIG_UNBLOCK, &blocked, 0); if (!ptyname) { emacs_close (fd); return -1; } snprintf (pty_name, PTY_NAME_SIZE, "%s", ptyname); }])
       dnl if HAVE_POSIX_OPENPT
       if test "x$ac_cv_func_posix_openpt" = xyes; then
-        AC_DEFINE(PTY_OPEN, [fd = posix_openpt (O_RDWR | O_CLOEXEC | O_NOCTTY)])
+        AC_DEFINE(PTY_OPEN, [do { fd = posix_openpt (O_RDWR | O_CLOEXEC | O_NOCTTY); if (fd < 0 && errno == EINVAL) fd = posix_openpt (O_RDWR | O_NOCTTY); } while (0)])
         AC_DEFINE(PTY_NAME_SPRINTF, [])
       dnl if HAVE_GETPT
       elif test "x$ac_cv_func_getpt" = xyes; then