Introduce command_line_up

This introduces command_line_up, a unique_ptr for command_line
objects, and changes many places to use it.  This removes a number of
cleanups.

Command lines are funny in that sometimes they are reference counted.
Once there is more C++-ification of some of the users, perhaps all of
these can be changed to use shared_ptr instead.

gdb/ChangeLog
2017-04-12  Tom Tromey  <tom@tromey.com>

	* tracepoint.c (actions_command): Update.
	* python/python.c (python_command, python_interactive_command):
	Update.
	* mi/mi-cmd-break.c (mi_cmd_break_commands): Update.
	* guile/guile.c (guile_command): Update.
	* defs.h (read_command_lines, read_command_lines_1): Return
	command_line_up.
	(command_lines_deleter): New struct.
	(command_line_up): New typedef.
	* compile/compile.c (compile_code_command)
	(compile_print_command): Update.
	* cli/cli-script.h (get_command_line, copy_command_lines): Return
	command_line_up.
	(make_cleanup_free_command_lines): Remove.
	* cli/cli-script.c (get_command_line, read_command_lines_1)
	(copy_command_lines): Return command_line_up.
	(while_command, if_command, read_command_lines, define_command)
	(document_command): Update.
	(do_free_command_lines_cleanup, make_cleanup_free_command_lines):
	Remove.
	* breakpoint.h (breakpoint_set_commands): Change type of
	"commands".
	* breakpoint.c (breakpoint_set_commands): Change type of
	"commands".  Update.
	(do_map_commands_command, update_dprintf_command_list)
	(create_tracepoint_from_upload): Update.

1 files changed, 21 insertions, 7 deletions

diff --git a/gdb/defs.h b/gdb/defs.h
index f689ec5..a0b586f 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -445,15 +445,29 @@ struct command_line
     struct command_line **body_list;
   };
 
-extern struct command_line *read_command_lines (char *, int, int,
-						void (*)(char *, void *),
-						void *);
-extern struct command_line *read_command_lines_1 (char * (*) (void), int,
-						  void (*)(char *, void *),
-						  void *);
-
 extern void free_command_lines (struct command_line **);
 
+/* A deleter for command_line that calls free_command_lines.  */
+
+struct command_lines_deleter
+{
+  void operator() (command_line *lines) const
+  {
+    free_command_lines (&lines);
+  }
+};
+
+/* A unique pointer to a command_line.  */
+
+typedef std::unique_ptr<command_line, command_lines_deleter> command_line_up;
+
+extern command_line_up read_command_lines (char *, int, int,
+					   void (*)(char *, void *),
+					   void *);
+extern command_line_up read_command_lines_1 (char * (*) (void), int,
+					     void (*)(char *, void *),
+					     void *);
+
 /* * Parameters of the "info proc" command.  */
 
 enum info_proc_what