[RFA 3/8] Replace clear_hook_in_cleanup with scoped_restore_hook_in

[Tom Tromey <tom@tromey.com>]

This removes clear_hook_in_cleanup in favor of a scoped_restore-like
class.  scoped_restore itself can't be used because hook_in is a
bitfield.

ChangeLog
2017-09-10  Tom Tromey  <tom@tromey.com>

	* cli/cli-script.c (class scoped_restore_hook_in): New.
	(clear_hook_in_cleanup): Remove.
	(execute_cmd_pre_hook, execute_cmd_post_hook): Use
	scoped_restore_hook_in.
---
 gdb/ChangeLog        |  7 +++++++
 gdb/cli/cli-script.c | 31 +++++++++++++++++++++----------
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index de88894..62d3d3c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,12 @@
 2017-09-10  Tom Tromey  <tom@tromey.com>
 
+	* cli/cli-script.c (class scoped_restore_hook_in): New.
+	(clear_hook_in_cleanup): Remove.
+	(execute_cmd_pre_hook, execute_cmd_post_hook): Use
+	scoped_restore_hook_in.
+
+2017-09-10  Tom Tromey  <tom@tromey.com>
+
 	* cli/cli-script.c (restore_interp): Remove.
 	(read_command_lines): Use scoped_restore_interp.
 	* interps.c (scoped_restore_interp::set_temp): Rename from
diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c
index 805064f..9b7ca12 100644
--- a/gdb/cli/cli-script.c
+++ b/gdb/cli/cli-script.c
@@ -340,23 +340,36 @@ print_command_lines (struct ui_out *uiout, struct command_line *cmd,
 
 /* Handle pre-post hooks.  */
 
-static void
-clear_hook_in_cleanup (void *data)
+class scoped_restore_hook_in
 {
-  struct cmd_list_element *c = (struct cmd_list_element *) data;
+public:
 
-  c->hook_in = 0; /* Allow hook to work again once it is complete.  */
-}
+  scoped_restore_hook_in (struct cmd_list_element *c)
+    : m_cmd (c)
+  {
+  }
+
+  ~scoped_restore_hook_in ()
+  {
+    m_cmd->hook_in = 0;
+  }
+
+  scoped_restore_hook_in (const scoped_restore_hook_in &) = delete;
+  scoped_restore_hook_in &operator= (const scoped_restore_hook_in &) = delete;
+
+private:
+
+  struct cmd_list_element *m_cmd;
+};
 
 void
 execute_cmd_pre_hook (struct cmd_list_element *c)
 {
   if ((c->hook_pre) && (!c->hook_in))
     {
-      struct cleanup *cleanups = make_cleanup (clear_hook_in_cleanup, c);
+      scoped_restore_hook_in restore_hook (c);
       c->hook_in = 1; /* Prevent recursive hooking.  */
       execute_user_command (c->hook_pre, (char *) 0);
-      do_cleanups (cleanups);
     }
 }
 
@@ -365,11 +378,9 @@ execute_cmd_post_hook (struct cmd_list_element *c)
 {
   if ((c->hook_post) && (!c->hook_in))
     {
-      struct cleanup *cleanups = make_cleanup (clear_hook_in_cleanup, c);
-
+      scoped_restore_hook_in restore_hook (c);
       c->hook_in = 1; /* Prevent recursive hooking.  */
       execute_user_command (c->hook_post, (char *) 0);
-      do_cleanups (cleanups);
     }
 }
 
-- 
2.9.4