Introduce a better dbm dump format.

* include/mailutils/dbm.h (mu_dbm_get_name): New prototype.
* libmu_dbm/name.c: New file.
* libmu_dbm/Makefile.am (libmu_dbm_la_SOURCES): Add name.c
* mu/dbm.c: New dump format.

@@ -73,6 +73,7 @@ int mu_dbm_safety_set_flags (mu_dbm_file_t db, int flags);
 int mu_dbm_safety_check (mu_dbm_file_t db);
 char const *mu_dbm_strerror (mu_dbm_file_t db);
 int mu_dbm_get_fd (mu_dbm_file_t db, int *pag, int *dir);
+int mu_dbm_get_name (mu_dbm_file_t db, const char **pname);
 
 int mu_dbm_impl_iterator (mu_iterator_t *itr);
 

@@ -29,6 +29,7 @@ libmu_dbm_la_SOURCES = \
  fetch.c\
  firstkey.c\
  getfd.c\
+ name.c\
  nextkey.c\
  open.c\
  safety.c\

 /* GNU Mailutils -- a suite of utilities for electronic mail
-   Copyright (C) 2011
-   Free Software Foundation, Inc.
+   Copyright (C) 2011 Free Software Foundation, Inc.
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <unistd.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/list.h>
+#include <mailutils/url.h>
+#include <mailutils/dbm.h>
+#include <mailutils/errno.h>
+#include <mailutils/util.h>
+#include "mudbm.h"
+
+int
+mu_dbm_get_name (mu_dbm_file_t db, const char **pname)
+{
+  if (!db)
+    return EINVAL;
+  if (!pname)
+    return MU_ERR_OUT_PTR_NULL;
+  *pname = db->db_name;
+  return 0;
+}