Change gdb_realpath to return a unique_xmalloc_ptr

This changes gdb_realpath to return a unique_xmalloc_ptr and fixes up
the callers.  This allows removing some cleanups.  This change by
itself caused xfullpath.exp to fail; and attempting to fix that ran
into various problems (like .get() being optimized out); so this patch
also rewrites xfullpath.exp to be a C++ selftest instead.

ChangeLog
2017-08-22  Tom Tromey  <tom@tromey.com>

	* exec.c (exec_file_attach): Update.
	* linux-thread-db.c (try_thread_db_load): Update.
	* guile/scm-safe-call.c (gdbscm_safe_source_script): Update.
	* utils.c (gdb_realpath): Change return type.
	(gdb_realpath_keepfile): Update.
	(gdb_realpath_check_trailer, gdb_realpath_tests): New functions.
	(_initialize_utils): Register the new self test.
	* source.c (openp): Update.
	(find_and_open_source): Update.
	* nto-tdep.c (nto_find_and_open_solib): Update.
	* main.c (set_gdb_data_directory): Update.
	(captured_main_1): Update.
	* dwarf2read.c (dwarf2_get_dwz_file): Update
	(dw2_map_symbol_filenames): Update.
	* auto-load.c (auto_load_safe_path_vec_update): Update.
	(filename_is_in_auto_load_safe_path_vec): Change type of
	"filename_realp".
	(auto_load_objfile_script): Update.
	(file_is_auto_load_safe): Update.  Use std::string.
	* utils.h (gdb_realpath): Return a gdb::unique_xmalloc_ptr.

testsuite/ChangeLog
2017-08-22  Tom Tromey  <tom@tromey.com>

	* gdb.gdb/xfullpath.exp: Remove.

1 files changed, 0 insertions, 60 deletions

diff --git a/gdb/testsuite/gdb.gdb/xfullpath.exp b/gdb/testsuite/gdb.gdb/xfullpath.exp
deleted file mode 100644
index 8c90693..0000000
--- a/gdb/testsuite/gdb.gdb/xfullpath.exp
+++ /dev/null
@@ -1,60 +0,0 @@
-# Copyright 2002-2017 Free Software Foundation, Inc.
-
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program 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 General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-# This file was written by Joel Brobecker. (brobecker@gnat.com), derived
-# from selftest.exp, written by Rob Savoye.
-
-load_lib selftest-support.exp
-
-proc test_with_self {} {
-    # A file which contains a directory prefix
-    gdb_test "print gdb_realpath (\"./xfullpath.exp\")" \
-             ".\[0-9\]+ =.*\".*/xfullpath.exp\"" \
-             "A filename with ./ as the directory prefix"
-
-    # A file which contains a directory prefix
-    gdb_test "print gdb_realpath (\"../../defs.h\")" \
-             ".\[0-9\]+ =.*\".*/defs.h\"" \
-             "A filename with ../ in the directory prefix"
-
-    # A one-character filename
-    gdb_test "print gdb_realpath (\"./a\")" \
-             ".\[0-9\]+ =.*\".*/a\"" \
-             "A one-char filename in the current directory"
-          
-    # A file in the root directory
-    gdb_test "print gdb_realpath (\"/root_file_which_should_exist\")" \
-             ".\[0-9\]+ =.*\"/root_file_which_should_exist\"" \
-             "A filename in the root directory"
-          
-    # A file which does not have a directory prefix
-    gdb_test "print gdb_realpath (\"xfullpath.exp\")" \
-             ".\[0-9\]+ =.*\"xfullpath.exp\"" \
-             "A filename without any directory prefix"
-
-    # A one-char filename without any directory prefix
-    gdb_test "print gdb_realpath (\"a\")" \
-             ".\[0-9\]+ =.*\"a\"" \
-             "A one-char filename without any directory prefix"
-
-    # An empty filename
-    gdb_test "print gdb_realpath (\"\")" \
-             ".\[0-9\]+ =.*\"\"" \
-             "an empty filename"
-
-    return 0
-}
-
-do_self_tests captured_main test_with_self