Use Gnulib 'tempname' on MS-Windows

* lib-src/ntlib.h (mkdir, open): Remove redefinitions.  They are
now in nt/inc/ms-w32.h.
* lib-src/ntlib.c (sys_mkdir, sys_open): New functions.
(mkostemp): Remove.

* src/w32.c (mkostemp): Remove.
(sys_mkdir): Accept a second (unused) argument.
* src/fileio.c (Fmake_directory_internal): Remove the WINDOWSNT
specific call to mkdir.  (Bug#28023)

* nt/inc/ms-w32.h (mkdir): Remove from "#ifdef emacs" and redefine
to accept 2 arguments.
(open): Remove from "#ifdef emacs".
* nt/mingw-cfg.site (ac_cv_func_mkostemp): Remove.
* nt/gnulib-cfg.mk (OMIT_GNULIB_MODULE_mkostemp)
(OMIT_GNULIB_MODULE_tempname): Remove.

lib-src/ntlib.c

@@ -36,9 +36,11 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 char *sys_ctime (const time_t *);
 FILE *sys_fopen (const char *, const char *);
+int sys_mkdir (const char *, mode_t);
 int sys_chdir (const char *);
 int mkostemp (char *, int);
 int sys_rename (const char *, const char *);
+int sys_open (const char *, int, int);
 
 /* MinGW64 defines _TIMEZONE_DEFINED and defines 'struct timespec' in
    its system headers.  */
@@ -245,6 +247,12 @@ sys_chdir (const char * path)
   return _chdir (path);
 }
 
+int
+sys_mkdir (const char * path, mode_t mode)
+{
+  return _mkdir (path);
+}
+
 static FILETIME utc_base_ft;
 static long double utc_base;
 static int init = 0;
@@ -396,61 +404,6 @@ lstat (const char * path, struct stat * buf)
   return stat (path, buf);
 }
 
-/* Implementation of mkostemp for MS-Windows, to avoid race conditions
-   when using mktemp.  Copied from w32.c.
-
-   This is used only in update-game-score.c.  It is overkill for that
-   use case, since update-game-score renames the temporary file into
-   the game score file, which isn't atomic on MS-Windows anyway, when
-   the game score already existed before running the program, which it
-   almost always does.  But using a simpler implementation just to
-   make a point is uneconomical...  */
-
-int
-mkostemp (char * template, int flags)
-{
-  char * p;
-  int i, fd = -1;
-  unsigned uid = GetCurrentThreadId ();
-  int save_errno = errno;
-  static char first_char[] = "abcdefghijklmnopqrstuvwyz0123456789!%-_@#";
-
-  errno = EINVAL;
-  if (template == NULL)
-    return -1;
-
-  p = template + strlen (template);
-  i = 5;
-  /* replace up to the last 5 X's with uid in decimal */
-  while (--p >= template && p[0] == 'X' && --i >= 0)
-    {
-      p[0] = '0' + uid % 10;
-      uid /= 10;
-    }
-
-  if (i < 0 && p[0] == 'X')
-    {
-      i = 0;
-      do
-	{
-	  p[0] = first_char[i];
-	  if ((fd = open (template,
-			  flags | _O_CREAT | _O_EXCL | _O_RDWR,
-			  S_IRUSR | S_IWUSR)) >= 0
-	      || errno != EEXIST)
-	    {
-	      if (fd >= 0)
-		errno = save_errno;
-	      return fd;
-	    }
-	}
-      while (++i < sizeof (first_char));
-    }
-
-  /* Template is badly formed or else we can't generate a unique name.  */
-  return -1;
-}
-
 /* On Windows, you cannot rename into an existing file.  */
 int
 sys_rename (const char *from, const char *to)
@@ -464,3 +417,9 @@ sys_rename (const char *from, const char *to)
     }
   return retval;
 }
+
+int
+sys_open (const char * path, int oflag, int mode)
+{
+  return _open (path, oflag, mode);
+}

lib-src/ntlib.h

@@ -58,10 +58,6 @@ int fchown (int fd, unsigned uid, unsigned gid);
 #undef dup2
 #define dup2    _dup2
 #undef fopen
-#undef mkdir
-#define mkdir   _mkdir
-#undef open
-#define open    _open
 #undef pipe
 #define pipe    _pipe
 #undef read

nt/gnulib-cfg.mk

@@ -50,7 +50,6 @@ OMIT_GNULIB_MODULE_dirfd = true
 OMIT_GNULIB_MODULE_fcntl = true
 OMIT_GNULIB_MODULE_fcntl-h = true
 OMIT_GNULIB_MODULE_inttypes-incomplete = true
-OMIT_GNULIB_MODULE_mkostemp = true
 OMIT_GNULIB_MODULE_pipe2 = true
 OMIT_GNULIB_MODULE_secure_getenv = true
 OMIT_GNULIB_MODULE_signal-h = true
@@ -60,5 +59,4 @@ OMIT_GNULIB_MODULE_sys_select = true
 OMIT_GNULIB_MODULE_sys_stat = true
 OMIT_GNULIB_MODULE_sys_time = true
 OMIT_GNULIB_MODULE_sys_types = true
-OMIT_GNULIB_MODULE_tempname = true
 OMIT_GNULIB_MODULE_unistd = true

nt/inc/ms-w32.h

@@ -237,9 +237,6 @@ extern void w32_reset_stack_overflow_guard (void);
 #define fopen   sys_fopen
 #define link    sys_link
 #define localtime sys_localtime
-#define mkdir   sys_mkdir
-#undef open
-#define open    sys_open
 #undef read
 #define read    sys_read
 #define rename  sys_rename
@@ -289,6 +286,10 @@ extern int sys_umask (int);
 
 #endif /* emacs */
 
+/* Used both in Emacs, in lib-src, and in Gnulib.  */
+#undef open
+#define open    sys_open
+
 /* Map to MSVC names.  */
 #define execlp    _execlp
 #define execvp    _execvp
@@ -465,6 +466,12 @@ extern char *get_emacs_configuration_options (void);
 #include <malloc.h>
 #endif
 
+/* Needed in Emacs and in Gnulib.  */
+/* This must be after including sys/stat.h, because we need mode_t.  */
+#undef mkdir
+#define mkdir(d,f)   sys_mkdir(d,f)
+int sys_mkdir (const char *, mode_t);
+
 #ifdef emacs
 
 typedef void * (* malloc_fn)(size_t);
@@ -518,9 +525,9 @@ extern int getpagesize (void);
 
 extern void * memrchr (void const *, int, size_t);
 
+/* Declared here, since we don't use Gnulib's stdlib.h.  */
 extern int mkostemp (char *, int);
 
-
 #if defined (__MINGW32__)
 
 /* Define to 1 if the system has the type `long long int'. */

nt/mingw-cfg.site

@@ -79,7 +79,6 @@ ac_cv_func_getaddrinfo=yes
 # Implemented as an inline function in ws2tcpip.h
 ac_cv_func_gai_strerror=yes
 # Implemented in w32.c
-ac_cv_func_mkostemp=yes
 ac_cv_func_readlink=yes
 ac_cv_func_symlink=yes
 # Avoid run-time tests of readlink and symlink, which will fail

src/fileio.c

@@ -2178,11 +2178,7 @@ DEFUN ("make-directory-internal", Fmake_directory_internal,
 
   dir = SSDATA (encoded_dir);
 
-#ifdef WINDOWSNT
-  if (mkdir (dir) != 0)
-#else
   if (mkdir (dir, 0777 & ~auto_saving_dir_umask) != 0)
-#endif
     report_file_error ("Creating directory", directory);
 
   return Qnil;

src/w32.c

@@ -74,7 +74,6 @@ char *sys_ctime (const time_t *);
 int sys_chdir (const char *);
 int sys_creat (const char *, int);
 FILE *sys_fopen (const char *, const char *);
-int sys_mkdir (const char *);
 int sys_open (const char *, int, int);
 int sys_rename (char const *, char const *);
 int sys_rmdir (const char *);
@@ -4344,7 +4343,7 @@ sys_link (const char * old, const char * new)
 }
 
 int
-sys_mkdir (const char * path)
+sys_mkdir (const char * path, mode_t mode)
 {
   path = map_w32_filename (path, NULL);
 
@@ -4397,61 +4396,6 @@ sys_open (const char * path, int oflag, int mode)
   return res;
 }
 
-/* Implementation of mkostemp for MS-Windows, to avoid race conditions
-   when using mktemp.
-
-   Standard algorithm for generating a temporary file name seems to be
-   use pid or tid with a letter on the front (in place of the 6 X's)
-   and cycle through the letters to find a unique name.  We extend
-   that to allow any reasonable character as the first of the 6 X's,
-   so that the number of simultaneously used temporary files will be
-   greater.  */
-
-int
-mkostemp (char * template, int flags)
-{
-  char * p;
-  int i, fd = -1;
-  unsigned uid = GetCurrentThreadId ();
-  int save_errno = errno;
-  static char first_char[] = "abcdefghijklmnopqrstuvwyz0123456789!%-_@#";
-
-  errno = EINVAL;
-  if (template == NULL)
-    return -1;
-
-  p = template + strlen (template);
-  i = 5;
-  /* replace up to the last 5 X's with uid in decimal */
-  while (--p >= template && p[0] == 'X' && --i >= 0)
-    {
-      p[0] = '0' + uid % 10;
-      uid /= 10;
-    }
-
-  if (i < 0 && p[0] == 'X')
-    {
-      i = 0;
-      do
-	{
-	  p[0] = first_char[i];
-	  if ((fd = sys_open (template,
-			      flags | _O_CREAT | _O_EXCL | _O_RDWR,
-			      S_IRUSR | S_IWUSR)) >= 0
-	      || errno != EEXIST)
-	    {
-	      if (fd >= 0)
-		errno = save_errno;
-	      return fd;
-	    }
-	}
-      while (++i < sizeof (first_char));
-    }
-
-  /* Template is badly formed or else we can't generate a unique name.  */
-  return -1;
-}
-
 int
 fchmod (int fd, mode_t mode)
 {