Keep compatibility with experimental implementation

---
 hurd/Makefile                       |    4 ++--
 hurd/Versions                       |    4 ++++
 hurd/hurdexec.c                     |   29 +++++++++++++++++++++++++++++
 sysdeps/mach/hurd/i386/libc.abilist |    1 +
 sysdeps/mach/hurd/spawni.c          |   13 +++++++++++++
 5 files changed, 49 insertions(+), 2 deletions(-)

--- a/hurd/Makefile
+++ b/hurd/Makefile
@@ -32,8 +32,8 @@
 				       auth auth_request auth_reply startup \
 				       process process_request \
 				       msg msg_reply msg_request \
-				       exec exec_startup crash interrupt \
-				       fs fsys io io_reply io_request \
+				       exec exec_experimental exec_startup crash interrupt \
+				       fs fs_experimental fsys io io_reply io_request \
 				       term tioctl socket ifsock \
 				       login password pfinet pci \
 				       )
--- a/hurd/Versions
+++ b/hurd/Versions
@@ -123,6 +123,10 @@
     # functions used in macros & inline functions
     __errno_location;
   }
+  GLIBC_2.21 {
+    # "quasi-internal" functions
+    _hurd_exec_file_name;
+  }
   GLIBC_2.26 {
     # "quasi-internal" functions
     _hurd_exec_paths;
--- a/hurd/hurdexec.c
+++ b/hurd/hurdexec.c
@@ -25,9 +25,12 @@
 #include <hurd/fd.h>
 #include <hurd/signal.h>
 #include <hurd/id.h>
+#include <hurd/fs_experimental.h>
 #include <assert.h>
 #include <argz.h>
 
+#include <shlib-compat.h>
+
 /* Overlay TASK, executing FILE with arguments ARGV and environment ENVP.
    If TASK == mach_task_self (), some ports are dealloc'd by the exec server.
    ARGV and ENVP are terminated by NULL pointers.
@@ -39,6 +42,13 @@
   return _hurd_exec_paths (task, file, NULL, NULL, argv, envp);
 }
 
+error_t
+__hurd_exec_file_name (task_t task, file_t file, const char *filename,
+	    char *const argv[], char *const envp[])
+{
+  return _hurd_exec_paths (task, file, filename, filename, argv, envp);
+}
+
 link_warning (_hurd_exec,
 	      "_hurd_exec is deprecated, use _hurd_exec_paths instead");
 
@@ -393,6 +403,19 @@
       /* Fall back for backwards compatibility.  This can just be removed
          when __file_exec goes away.  */
       if (err == MIG_BAD_ID)
+	err = __file_exec_file_name (file, task, flags,
+				    path ? path : "",
+				    args, argslen, env, envlen,
+				    dtable, MACH_MSG_TYPE_COPY_SEND, dtablesize,
+				    ports, MACH_MSG_TYPE_COPY_SEND,
+				    _hurd_nports,
+				    ints, INIT_INT_MAX,
+				    please_dealloc, pdp - please_dealloc,
+				    &_hurd_msgport,
+				    task == __mach_task_self () ? 1 : 0);
+      /* Fall back for backwards compatibility.  This can just be removed
+         when __file_exec goes away.  */
+      if (err == MIG_BAD_ID)
 	err = __file_exec (file, task, flags,
 			   args, argslen, env, envlen,
 			   dtable, MACH_MSG_TYPE_COPY_SEND, dtablesize,
@@ -436,3 +459,9 @@
   return err;
 }
 libc_hidden_def (_hurd_exec_paths)
+extern error_t _hurd_exec_file_name (task_t task,
+				     file_t file,
+				     const char *filename,
+				     char *const argv[],
+				     char *const envp[]);
+versioned_symbol (libc, __hurd_exec_file_name, _hurd_exec_file_name, GLIBC_2_21);
--- a/sysdeps/mach/hurd/spawni.c
+++ b/sysdeps/mach/hurd/spawni.c
@@ -30,6 +30,7 @@
 #include <hurd/id.h>
 #include <hurd/lookup.h>
 #include <hurd/resource.h>
+#include <hurd/fs_experimental.h>
 #include <assert.h>
 #include <argz.h>
 #include "spawn_int.h"
@@ -770,6 +771,18 @@
 	   dtable, MACH_MSG_TYPE_COPY_SEND, dtablesize,
 	   ports, MACH_MSG_TYPE_COPY_SEND, _hurd_nports,
 	   ints, INIT_INT_MAX,
+	   NULL, 0, NULL, 0);
+
+	/* Fallback for backwards compatibility.  This can just be removed
+	   when __file_exec goes away.  */
+	if (err == MIG_BAD_ID)
+	  err = __file_exec_file_name
+	  (file, task,
+	   __sigismember (&_hurdsig_traced, SIGKILL) ? EXEC_SIGTRAP : 0,
+	   relpath, args, argslen, env, envlen,
+	   dtable, MACH_MSG_TYPE_COPY_SEND, dtablesize,
+	   ports, MACH_MSG_TYPE_COPY_SEND, _hurd_nports,
+	   ints, INIT_INT_MAX,
 	   NULL, 0, NULL, 0);
 
 	/* Fallback for backwards compatibility.  This can just be removed
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -1947,6 +1947,7 @@
 GLIBC_2.2.6 xprt_unregister F
 GLIBC_2.21 __mach_host_self_ D 0x4
 GLIBC_2.21 __pthread_get_cleanup_stack F
+GLIBC_2.21 _hurd_exec_file_name F
 GLIBC_2.21 mach_print F
 GLIBC_2.21 pthread_attr_destroy F
 GLIBC_2.21 pthread_attr_getdetachstate F