Merge branch 'trunk' into xwidget

Conflicts:
	src/xdisp.c

1 files changed, 15 insertions, 5 deletions

diff --git a/src/filelock.c b/src/filelock.c
index de6aba8385c..244663ad20a 100644
--- a/src/filelock.c
+++ b/src/filelock.c
@@ -47,6 +47,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "systime.h"
 #ifdef WINDOWSNT
 #include <share.h>
+#include <sys/socket.h> /* for fcntl */
 #include "w32.h"        /* for dostounix_filename */
 #endif
 
@@ -380,9 +381,9 @@ rename_lock_file (char const *old, char const *new, bool force)
 #endif
 }
 
-/* Create the lock file FILE with contents CONTENTS.  Return 0 if
+/* Create the lock file LFNAME with contents LOCK_INFO_STR.  Return 0 if
    successful, an errno value on failure.  If FORCE, remove any
-   existing FILE if necessary.  */
+   existing LFNAME if necessary.  */
 
 static int
 create_lock_file (char *lfname, char *lock_info_str, bool force)
@@ -416,8 +417,13 @@ create_lock_file (char *lfname, char *lock_info_str, bool force)
       memcpy (nonce, lfname, lfdirlen);
       strcpy (nonce + lfdirlen, nonce_base);
 
-#if HAVE_MKSTEMP
-      /* Prefer mkstemp if available, as it avoids a race between
+#if HAVE_MKOSTEMP
+      /* Prefer mkostemp to mkstemp, as it avoids a window where FD is
+         temporarily open without close-on-exec.  */
+      fd = mkostemp (nonce, O_BINARY | O_CLOEXEC);
+      need_fchmod = 1;
+#elif HAVE_MKSTEMP
+      /* Prefer mkstemp to mktemp, as it avoids a race between
          mktemp and emacs_open.  */
       fd = mkstemp (nonce);
       need_fchmod = 1;
@@ -432,7 +438,11 @@ create_lock_file (char *lfname, char *lock_info_str, bool force)
         err = errno;
       else
         {
-          ptrdiff_t lock_info_len = strlen (lock_info_str);
+          ptrdiff_t lock_info_len;
+#if ! HAVE_MKOSTEMP
+          fcntl (fd, F_SETFD, FD_CLOEXEC);
+#endif
+          lock_info_len = strlen (lock_info_str);
           err = 0;
           if (emacs_write (fd, lock_info_str, lock_info_len) != lock_info_len
               || (need_fchmod && fchmod (fd, world_readable) != 0))