gdb: Make ldirname return a std::string

Eliminates several uses of cleanups.

Tested on x86_64 Fedora 23 with Python 2 and 3.

gdb/ChangeLog
2017-03-27  Pedro Alves  <palves@redhat.com>

	* dwarf2read.c (struct file_and_directory): New.
	(dwarf2_get_dwz_file): Adjust to use std::string.
	(dw2_get_file_names_reader): Adjust to use file_and_directory.
	(find_file_and_directory): Adjust to return a file_and_directory
	object.
	(read_file_scope): Adjust to use file_and_directory.  Remove
	make_cleanup/do_cleanups calls.
	(open_and_init_dwp_file): Adjust to use std::string.  Remove
	make_cleanup/do_cleanups calls.
	* python/python.c (do_start_initialization): Adjust to ldirname
	returning a std::string.
	* utils.c (ldirname): Now returns a std::string.
	* utils.h (ldirname): Change return type to std::string.
	* xml-syscall.c (xml_init_syscalls_info): Adjust to ldirname
	returning a std::string.
	* xml-tdesc.c (file_read_description_xml): Likewise.

1 files changed, 2 insertions, 6 deletions

diff --git a/gdb/xml-syscall.c b/gdb/xml-syscall.c
index 1e42b8d..a436418 100644
--- a/gdb/xml-syscall.c
+++ b/gdb/xml-syscall.c
@@ -363,7 +363,6 @@ static struct syscalls_info *
 xml_init_syscalls_info (const char *filename)
 {
   char *full_file;
-  char *dirname;
   struct syscalls_info *syscalls_info;
   struct cleanup *back_to;
 
@@ -373,12 +372,9 @@ xml_init_syscalls_info (const char *filename)
 
   back_to = make_cleanup (xfree, full_file);
 
-  dirname = ldirname (filename);
-  if (dirname != NULL)
-    make_cleanup (xfree, dirname);
-
   syscalls_info = syscall_parse_xml (full_file,
-				     xml_fetch_content_from_file, dirname);
+				     xml_fetch_content_from_file,
+				     (void *) ldirname (filename).c_str ());
   do_cleanups (back_to);
 
   return syscalls_info;