Use closefrom() if available

ChangeLog

@@ -1,3 +1,11 @@
+2023-11-14 Richard Frith-Macdonald <rfm@gnu.org>
+
+	* configure.ac: Add check for closefrom()
+	* configure: regenerate
+	* Headers/GNUstepBase/config.h.in: regenerate
+	* Source/NSTask.m: Use closefrom() to close descriptors in child
+	process if it is available.
+
 2023-10-26 Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/NSISO8601DateFormatter.m:

Headers/GNUstepBase/config.h.in

@@ -198,6 +198,9 @@
 /* Define to 1 if you have the <callback.h> header file. */
 #undef HAVE_CALLBACK_H
 
+/* Define to 1 if you have the `closefrom' function. */
+#undef HAVE_CLOSEFROM
+
 /* Define to 1 if you have the `ctime' function. */
 #undef HAVE_CTIME
 

Source/NSTask.m

@@ -1773,10 +1773,14 @@ GSPrivateCheckTasks()
       /*
        * Close any extra descriptors.
        */
+#if	defined(HAVE_CLOSEFROM)
+      closefrom(3);
+#else
       for (i = 3; i < NOFILE; i++)
 	{
 	  (void) close(i);
 	}
+#endif
 
       if (0 != chdir(path))
         {

configure

@@ -10167,6 +10167,17 @@ _ACEOF
 fi
 done
 
+for ac_func in closefrom
+do :
+  ac_fn_c_check_func "$LINENO" "closefrom" "ac_cv_func_closefrom"
+if test "x$ac_cv_func_closefrom" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_CLOSEFROM 1
+_ACEOF
+
+fi
+done
+
 if test "x$ac_cv_func_setpgrp" = xyes; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether setpgrp takes no argument" >&5
 $as_echo_n "checking whether setpgrp takes no argument... " >&6; }

configure.ac

@@ -2592,6 +2592,7 @@ AC_CHECK_HEADERS(sys/mman.h)
 # These functions needed by NSTask.m
 #--------------------------------------------------------------------
 AC_CHECK_FUNCS(killpg setpgrp setpgid setsid grantpt)
+AC_CHECK_FUNCS(closefrom)
 if test "x$ac_cv_func_setpgrp" = xyes; then
   AC_FUNC_SETPGRP
 fi