login: Remove utmp backend jump tables [BZ #23518]

There is just one file-based implementation, so this dispatch
mechanism is unnecessary.  Instead of the vtable pointer
__libc_utmp_jump_table, use a non-negative file_fd as the indicator
that the backend is initialized.

1 files changed, 3 insertions, 4 deletions

diff --git a/sysdeps/unix/getlogin_r.c b/sysdeps/unix/getlogin_r.c
index 6c564d3b59..88971a9931 100644
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -64,8 +64,8 @@ __getlogin_r (char *name, size_t name_len)
      held so that our search is thread-safe.  */
 
   __libc_lock_lock (__libc_utmp_lock);
-  (*__libc_utmp_jump_table->setutent) ();
-  result = (*__libc_utmp_jump_table->getutline_r) (&line, &buffer, &ut);
+  __libc_setutent ();
+  result = __libc_getutline_r (&line, &buffer, &ut);
   if (result < 0)
     {
       if (errno == ESRCH)
@@ -74,8 +74,7 @@ __getlogin_r (char *name, size_t name_len)
       else
 	result = errno;
     }
-  (*__libc_utmp_jump_table->endutent) ();
-  __libc_utmp_jump_table = &__libc_utmp_unknown_functions;
+  __libc_endutent ();
   __libc_lock_unlock (__libc_utmp_lock);
 
   if (result == 0)