Return unique_xmalloc_ptr from target_read_stralloc

This changes target_read_stralloc to return a unique_xmalloc_ptr, and
then fixes all the callers.  unique_xmalloc_ptr is used, rather than
std::string, because target_read_stralloc gives a special meaning to a
NULL return.

ChangeLog
2017-10-16  Tom Tromey  <tom@tromey.com>

	* xml-syscall.c (xml_init_syscalls_info): Update.
	* xml-support.c (xinclude_start_include): Update.
	(xml_fetch_content_from_file): Return unique_xmalloc_ptr.
	* xml-support.h (xml_fetch_another): Return unique_xmalloc_ptr.
	(xml_fetch_content_from_file): Likewise.
	* osdata.c (get_osdata): Update.
	* target.h (target_read_stralloc, target_get_osdata): Return
	unique_xmalloc_ptr.
	* solib-aix.c (solib_aix_get_library_list): Update.
	* solib-target.c (solib_target_current_sos): Update.
	* solib-svr4.c (svr4_current_sos_via_xfer_libraries): Update.
	* xml-tdesc.c (fetch_available_features_from_target): Update.
	(target_fetch_description_xml): Update.
	(file_read_description_xml): Update.
	* remote.c (remote_get_threads_with_qxfer, remote_memory_map)
	(remote_traceframe_info, btrace_read_config, remote_read_btrace)
	(remote_pid_to_exec_file): Update.
	* target.c (target_read_stralloc): Return unique_xmalloc_ptr.
	(target_get_osdata): Likewise.

1 files changed, 5 insertions, 10 deletions

diff --git a/gdb/solib-aix.c b/gdb/solib-aix.c
index 9233e78..de238e5 100644
--- a/gdb/solib-aix.c
+++ b/gdb/solib-aix.c
@@ -271,39 +271,34 @@ static VEC (lm_info_aix_p) *
 solib_aix_get_library_list (struct inferior *inf, const char *warning_msg)
 {
   struct solib_aix_inferior_data *data;
-  char *library_document;
-  struct cleanup *cleanup;
 
   /* If already computed, return the cached value.  */
   data = get_solib_aix_inferior_data (inf);
   if (data->library_list != NULL)
     return data->library_list;
 
-  library_document = target_read_stralloc (&current_target,
-                                           TARGET_OBJECT_LIBRARIES_AIX,
-                                           NULL);
+  gdb::unique_xmalloc_ptr<char> library_document
+    = target_read_stralloc (&current_target, TARGET_OBJECT_LIBRARIES_AIX,
+			    NULL);
   if (library_document == NULL && warning_msg != NULL)
     {
       warning (_("%s (failed to read TARGET_OBJECT_LIBRARIES_AIX)"),
 	       warning_msg);
       return NULL;
     }
-  cleanup = make_cleanup (xfree, library_document);
 
   if (solib_aix_debug)
     fprintf_unfiltered (gdb_stdlog,
 			"DEBUG: TARGET_OBJECT_LIBRARIES_AIX = \n%s\n",
-			library_document);
+			library_document.get ());
 
-  data->library_list = solib_aix_parse_libraries (library_document);
+  data->library_list = solib_aix_parse_libraries (library_document.get ());
   if (data->library_list == NULL && warning_msg != NULL)
     {
       warning (_("%s (missing XML support?)"), warning_msg);
-      do_cleanups (cleanup);
       return NULL;
     }
 
-  do_cleanups (cleanup);
   return data->library_list;
 }