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Diffstat (limited to 'sysdeps/unix/getlogin.c')
-rw-r--r--sysdeps/unix/getlogin.c54
1 files changed, 19 insertions, 35 deletions
diff --git a/sysdeps/unix/getlogin.c b/sysdeps/unix/getlogin.c
index 504a7aa4c0..00baf6875a 100644
--- a/sysdeps/unix/getlogin.c
+++ b/sysdeps/unix/getlogin.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1992, 1996 Free Software Foundation, Inc.
 This file is part of the GNU C Library.
 
 The GNU C Library is free software; you can redistribute it and/or
@@ -17,7 +17,6 @@ not, write to the Free Software Foundation, Inc., 675 Mass Ave,
 Cambridge, MA 02139, USA.  */
 
 #include <ansidecl.h>
-#include <stddef.h>
 #include <errno.h>
 #include <unistd.h>
 #include <string.h>
@@ -27,38 +26,29 @@ Cambridge, MA 02139, USA.  */
 
 #include <utmp.h>
 
-/* Defined in ttyname.c.  */
-extern char *__ttyname;
-
 /* Return the login name of the user, or NULL if it can't be determined.
    The returned pointer, if not NULL, is good only until the next call.  */
 
 char *
 DEFUN_VOID(getlogin)
 {
-  char save_tty_pathname[2 + 2 * NAME_MAX];
-  char *save_ttyname;
-  char *real_tty_path;
+  char tty_pathname[2 + 2 * NAME_MAX];
+  char *real_tty_path = tty_pathname;
   char *result = NULL;
-  FILE *f;
-  static struct utmp ut;
-
-  if (__ttyname == NULL)
-    save_ttyname = NULL;
-  else
-    save_ttyname = strcpy (save_tty_pathname, __ttyname);
+  static struct utmp_data utmp_data;
+  struct utmp *ut;
 
   {
-    int err;
+    int err = 0;
     int d = __open ("/dev/tty", 0);
     if (d < 0)
       return NULL;
 
-    real_tty_path = ttyname (d);
-    err = errno;
+    if (ttyname_r (d, real_tty_path, sizeof (tty_pathname)) < 0)
+      err = errno;
     (void) close (d);
 
-    if (real_tty_path == NULL)
+    if (errno != 0)
       {
 	errno = err;
 	return NULL;
@@ -67,24 +57,18 @@ DEFUN_VOID(getlogin)
 
   real_tty_path += 5;		/* Remove "/dev/".  */
 
-  f = fopen ("/etc/utmp", "r");
-  if (f != NULL)
+  setutent_r (&utmp_data);
+  if (getutline_r (real_tty_path, &ut, &utmp_data) < 0)
     {
-      while (fread ((PTR) &ut, sizeof(ut), 1, f) == 1)
-	if (!strncmp (ut.ut_line, real_tty_path, sizeof (ut.ut_line)))
-	  {
-	    result = ut.ut_name;
-	    /* The name is not null-terminated if
-	       it is as long as sizeof (ut.ut_name).  */
-	    result[sizeof (ut.ut_name)] = '\0';
-	    break;
-	  }
-      (void) fclose (f);
+      if (errno == ESRCH)
+	/* The caller expects ENOENT if nothing is found.  */
+	errno = ENOENT;
+      result = NULL;
     }
+  else
+    result = ut->ut_line;
+
+  endutent_r (&utmp_data);
 
-  if (save_ttyname != NULL)
-    strcpy (__ttyname, save_ttyname);
-  if (result == NULL)
-    errno = ENOENT;
   return result;
 }