Merge from Gnulib; use ‘open’ for O_CLOEXEC

This incorporates:
2017-08-15 renameat: ensure declaration in <stdio.h> on NetBSD
2017-08-15 extensions: enable NetBSD specific extensions
2017-08-14 open: support O_CLOEXEC
2017-08-13 reallocarray: new module
* admin/merge-gnulib (AVOIDED_MODULES): Remove ‘open’, since
it now supports O_CLOEXEC and this simplifies Emacs.
* build-aux/config.guess, lib/fcntl.in.h, lib/stdio.in.h:
* lib/stdlib.in.h, m4/extensions.m4, m4/stdlib_h.m4:
Copy from Gnulib.
* lib/cloexec.c, lib/cloexec.h, lib/open.c:
* m4/mode_t.m4, m4/open-cloexec.m4, m4/open.m4:
New files, copied from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib-src/etags.c (O_CLOEXEC) [WINDOWSNT]:
Remove, as Gnulib does this for us.
* src/filelock.c (create_lock_file):
* src/sysdep.c (emacs_open, emacs_pipe):
Don’t worry about O_CLOEXEC == 0, as Gnulib no longer sets it to 0.

2 files changed, 1 insertions, 11 deletions

diff --git a/src/filelock.c b/src/filelock.c
index 3d6941695ae..fec9bc044ae 100644
--- a/src/filelock.c
+++ b/src/filelock.c
@@ -403,8 +403,6 @@ create_lock_file (char *lfname, char *lock_info_str, bool force)
       else
         {
           ptrdiff_t lock_info_len;
-          if (! O_CLOEXEC)
-            fcntl (fd, F_SETFD, FD_CLOEXEC);
           lock_info_len = strlen (lock_info_str);
           err = 0;
           if (emacs_write (fd, lock_info_str, lock_info_len) != lock_info_len
diff --git a/src/sysdep.c b/src/sysdep.c
index 2e18a419e3f..12e9c83ee90 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -2393,8 +2393,6 @@ emacs_open (const char *file, int oflags, int mode)
   oflags |= O_CLOEXEC;
   while ((fd = open (file, oflags, mode)) < 0 && errno == EINTR)
     maybe_quit ();
-  if (! O_CLOEXEC && 0 <= fd)
-    fcntl (fd, F_SETFD, FD_CLOEXEC);
   return fd;
 }
 
@@ -2436,13 +2434,7 @@ emacs_pipe (int fd[2])
 #ifdef MSDOS
   return pipe (fd);
 #else  /* !MSDOS */
-  int result = pipe2 (fd, O_BINARY | O_CLOEXEC);
-  if (! O_CLOEXEC && result == 0)
-    {
-      fcntl (fd[0], F_SETFD, FD_CLOEXEC);
-      fcntl (fd[1], F_SETFD, FD_CLOEXEC);
-    }
-  return result;
+  return pipe2 (fd, O_BINARY | O_CLOEXEC);
 #endif  /* !MSDOS */
 }