Eliminate make_cleanup_ui_file_deleteusers/palves/cxx-eliminate-cleanups

And now that ui_file_as_string is in, let's eliminate it.  :-)

Makes ui_file a real C++ hierarchy.  mem_fileopen is replaced with a
new string_file class that is treated as a value class created on the
stack.  This alone eliminates most make_cleanup_ui_file_delete calls,
and, simplifies code a whole lot (diffstat shows almost 1k loc
dropped.)

string_file has a string() method that gives you a direct reference to
the internal std::string.  This is what replaces old (well, new)
ui_file_as_string, which used to alway return a new copy of the same
data the stream had inside..  With direct access via a writable
reference, we can instead move the string out of the string_stream.

Note I needed a tweak on scoped_restore.  That one should probably be
split out to a separate patch.

This exposed the need to make use of gnulib namespace support.
Otherwise, making use of read/write/printf/puts/etc symbol names will
clash on systems where gnulib replaces those functions, due to
'#define foo rpl_foo'.

1 files changed, 6 insertions, 8 deletions

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 0f9f0f3b86c..5b51d030586 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -9578,7 +9578,6 @@ extern initialize_file_ftype _initialize_arm_tdep; /* -Wmissing-prototypes */
 void
 _initialize_arm_tdep (void)
 {
-  struct ui_file *stb;
   long length;
   const char *setname;
   const char *setdesc;
@@ -9650,13 +9649,12 @@ _initialize_arm_tdep (void)
   valid_disassembly_styles[num_disassembly_options] = NULL;
 
   /* Create the help text.  */
-  stb = mem_fileopen ();
-  fprintf_unfiltered (stb, "%s%s%s",
-		      _("The valid values are:\n"),
-		      regdesc,
-		      _("The default is \"std\"."));
-  helptext = ui_file_as_string (stb);
-  ui_file_delete (stb);
+  string_file stb;
+  stb.printf ("%s%s%s",
+	      _("The valid values are:\n"),
+	      regdesc,
+	      _("The default is \"std\"."));
+  helptext = std::move (stb.string ());
 
   add_setshow_enum_cmd("disassembler", no_class,
 		       valid_disassembly_styles, &disassembly_style,