[binutils-gdb] Eliminate TUI/CLI observers duplication

[binutils-gdb] Eliminate TUI/CLI observers duplication

[Pedro Alves]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5227abd299c632f66505f827cd221fe4bd7f4d0d

commit 5227abd299c632f66505f827cd221fe4bd7f4d0d
Author: Pedro Alves <pedro@palves.net>
Date:   Wed Jun 22 17:03:50 2022 +0100

    Eliminate TUI/CLI observers duplication
    
    For historical reasons, the CLI and the TUI observers are basically
    exact duplicates, except for the downcast:
    
     cli:
           struct cli_interp *cli = as_cli_interp (interp);
     tui:
           struct interp *tui = as_tui_interp (interp);
    
    and how they get at the interpreter's ui_out:
    
     cli:
           cli->cli_uiout
     tui:
           tui->interp_ui_out ()
    
    Since interp_ui_out() is a virtual method that also works for the CLI
    interpreter, and, both the CLI and the TUI interpreters inherit from
    the same base class (cli_interp_base), we can convert the CLI
    observers to cast to cli_interp_base instead and use interp_ui_out()
    too.  With that, the CLI observers will work for the TUI interpreter
    as well.  This lets us completely eliminate the TUI observers.  That's
    what this commit does.
    
    Change-Id: Iaf6cf12dfa200ed3ab203a895a72b69dfedbd6e0

Diff:
---
 gdb/cli/cli-interp.c | 127 +++++++++++++++++-----------------
 gdb/tui/tui-interp.c | 190 +--------------------------------------------------
 2 files changed, 64 insertions(+), 253 deletions(-)

diff --git a/gdb/cli/cli-interp.c b/gdb/cli/cli-interp.c
index fe9e4b43f14..036bc723b24 100644
--- a/gdb/cli/cli-interp.c
+++ b/gdb/cli/cli-interp.c
@@ -70,13 +70,13 @@ cli_interp::~cli_interp ()
 /* Suppress notification struct.  */
 struct cli_suppress_notification cli_suppress_notification;
 
-/* Returns the INTERP's data cast as cli_interp if INTERP is a CLI,
-   and returns NULL otherwise.  */
+/* Returns the INTERP's data cast as cli_interp_base if INTERP is a
+   console-like interpreter, and returns NULL otherwise.  */
 
-static struct cli_interp *
-as_cli_interp (struct interp *interp)
+static cli_interp_base *
+as_cli_interp_base (interp *interp)
 {
-  return dynamic_cast<cli_interp *> (interp);
+  return dynamic_cast<cli_interp_base *> (interp);
 }
 
 /* Longjmp-safe wrapper for "execute_command".  */
@@ -117,12 +117,13 @@ should_print_stop_to_console (struct interp *console_interp,
 
 /* Observers for several run control events.  If the interpreter is
    quiet (i.e., another interpreter is being run with
-   interpreter-exec), print nothing.  */
+   interpreter-exec), print nothing.  These are named "cli_base" as
+   they print to both CLI interpreters and TUI interpreters.  */
 
 /* Observer for the normal_stop notification.  */
 
 static void
-cli_on_normal_stop (struct bpstat *bs, int print_frame)
+cli_base_on_normal_stop (struct bpstat *bs, int print_frame)
 {
   if (!print_frame)
     return;
@@ -134,106 +135,98 @@ cli_on_normal_stop (struct bpstat *bs, int print_frame)
   SWITCH_THRU_ALL_UIS ()
     {
       struct interp *interp = top_level_interpreter ();
-      struct cli_interp *cli = as_cli_interp (interp);
-      struct thread_info *thread;
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (interp);
+      if (cli == nullptr)
 	continue;
 
-      thread = inferior_thread ();
+      thread_info *thread = inferior_thread ();
       if (should_print_stop_to_console (interp, thread))
-	print_stop_event (cli->cli_uiout);
+	print_stop_event (cli->interp_ui_out ());
     }
 }
 
 /* Observer for the signal_received notification.  */
 
 static void
-cli_on_signal_received (enum gdb_signal siggnal)
+cli_base_on_signal_received (enum gdb_signal siggnal)
 {
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
-      print_signal_received_reason (cli->cli_uiout, siggnal);
+      print_signal_received_reason (cli->interp_ui_out (), siggnal);
     }
 }
 
 /* Observer for the end_stepping_range notification.  */
 
 static void
-cli_on_end_stepping_range (void)
+cli_base_on_end_stepping_range ()
 {
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
-      print_end_stepping_range_reason (cli->cli_uiout);
+      print_end_stepping_range_reason (cli->interp_ui_out ());
     }
 }
 
 /* Observer for the signalled notification.  */
 
 static void
-cli_on_signal_exited (enum gdb_signal siggnal)
+cli_base_on_signal_exited (enum gdb_signal siggnal)
 {
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
-      print_signal_exited_reason (cli->cli_uiout, siggnal);
+      print_signal_exited_reason (cli->interp_ui_out (), siggnal);
     }
 }
 
 /* Observer for the exited notification.  */
 
 static void
-cli_on_exited (int exitstatus)
+cli_base_on_exited (int exitstatus)
 {
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
-      print_exited_reason (cli->cli_uiout, exitstatus);
+      print_exited_reason (cli->interp_ui_out (), exitstatus);
     }
 }
 
 /* Observer for the no_history notification.  */
 
 static void
-cli_on_no_history (void)
+cli_base_on_no_history ()
 {
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
-      print_no_history_reason (cli->cli_uiout);
+      print_no_history_reason (cli->interp_ui_out ());
     }
 }
 
 /* Observer for the sync_execution_done notification.  */
 
 static void
-cli_on_sync_execution_done (void)
+cli_base_on_sync_execution_done ()
 {
-  struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-  if (cli == NULL)
+  cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+  if (cli == nullptr)
     return;
 
   display_gdb_prompt (NULL);
@@ -242,11 +235,10 @@ cli_on_sync_execution_done (void)
 /* Observer for the command_error notification.  */
 
 static void
-cli_on_command_error (void)
+cli_base_on_command_error ()
 {
-  struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-  if (cli == NULL)
+  cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+  if (cli == nullptr)
     return;
 
   display_gdb_prompt (NULL);
@@ -255,27 +247,26 @@ cli_on_command_error (void)
 /* Observer for the user_selected_context_changed notification.  */
 
 static void
-cli_on_user_selected_context_changed (user_selected_what selection)
+cli_base_on_user_selected_context_changed (user_selected_what selection)
 {
   /* This event is suppressed.  */
   if (cli_suppress_notification.user_selected_context)
     return;
 
-  thread_info *tp = inferior_ptid != null_ptid ? inferior_thread () : NULL;
+  thread_info *tp = inferior_ptid != null_ptid ? inferior_thread () : nullptr;
 
   SWITCH_THRU_ALL_UIS ()
     {
-      struct cli_interp *cli = as_cli_interp (top_level_interpreter ());
-
-      if (cli == NULL)
+      cli_interp_base *cli = as_cli_interp_base (top_level_interpreter ());
+      if (cli == nullptr)
 	continue;
 
       if (selection & USER_SELECTED_INFERIOR)
-	print_selected_inferior (cli->cli_uiout);
+	print_selected_inferior (cli->interp_ui_out ());
 
-      if (tp != NULL
+      if (tp != nullptr
 	  && ((selection & (USER_SELECTED_THREAD | USER_SELECTED_FRAME))))
-	print_selected_thread_frame (cli->cli_uiout, selection);
+	print_selected_thread_frame (cli->interp_ui_out (), selection);
     }
 }
 
@@ -465,17 +456,21 @@ _initialize_cli_interp ()
 {
   interp_factory_register (INTERP_CONSOLE, cli_interp_factory);
 
-  /* If changing this, remember to update tui-interp.c as well.  */
-  gdb::observers::normal_stop.attach (cli_on_normal_stop, "cli-interp");
-  gdb::observers::end_stepping_range.attach (cli_on_end_stepping_range,
-					     "cli-interp");
-  gdb::observers::signal_received.attach (cli_on_signal_received, "cli-interp");
-  gdb::observers::signal_exited.attach (cli_on_signal_exited, "cli-interp");
-  gdb::observers::exited.attach (cli_on_exited, "cli-interp");
-  gdb::observers::no_history.attach (cli_on_no_history, "cli-interp");
-  gdb::observers::sync_execution_done.attach (cli_on_sync_execution_done,
-					      "cli-interp");
-  gdb::observers::command_error.attach (cli_on_command_error, "cli-interp");
+  /* Note these all work for both the CLI and TUI interpreters.  */
+  gdb::observers::normal_stop.attach (cli_base_on_normal_stop,
+				      "cli-interp-base");
+  gdb::observers::end_stepping_range.attach (cli_base_on_end_stepping_range,
+					     "cli-interp-base");
+  gdb::observers::signal_received.attach (cli_base_on_signal_received,
+					  "cli-interp-base");
+  gdb::observers::signal_exited.attach (cli_base_on_signal_exited,
+					"cli-interp-base");
+  gdb::observers::exited.attach (cli_base_on_exited, "cli-interp-base");
+  gdb::observers::no_history.attach (cli_base_on_no_history, "cli-interp-base");
+  gdb::observers::sync_execution_done.attach (cli_base_on_sync_execution_done,
+					      "cli-interp-base");
+  gdb::observers::command_error.attach (cli_base_on_command_error,
+					"cli-interp-base");
   gdb::observers::user_selected_context_changed.attach
-    (cli_on_user_selected_context_changed, "cli-interp");
+    (cli_base_on_user_selected_context_changed, "cli-interp-base");
 }
diff --git a/gdb/tui/tui-interp.c b/gdb/tui/tui-interp.c
index b4faede8ce6..1c4ffbbc3aa 100644
--- a/gdb/tui/tui-interp.c
+++ b/gdb/tui/tui-interp.c
@@ -53,15 +53,6 @@ public:
   ui_out *interp_ui_out () override;
 };
 
-/* Returns the INTERP if the INTERP is a TUI, and returns NULL
-   otherwise.  */
-
-static tui_interp *
-as_tui_interp (struct interp *interp)
-{
-  return dynamic_cast<tui_interp *> (interp);
-}
-
 /* Cleanup the tui before exiting.  */
 
 static void
@@ -72,171 +63,6 @@ tui_exit (void)
   tui_disable ();
 }
 
-/* Observers for several run control events.  If the interpreter is
-   quiet (i.e., another interpreter is being run with
-   interpreter-exec), print nothing.  */
-
-/* Observer for the normal_stop notification.  */
-
-static void
-tui_on_normal_stop (struct bpstat *bs, int print_frame)
-{
-  if (!print_frame)
-    return;
-
-  /* This event is suppressed.  */
-  if (cli_suppress_notification.normal_stop)
-    return;
-
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *interp = top_level_interpreter ();
-      struct interp *tui = as_tui_interp (interp);
-      struct thread_info *thread;
-
-      if (tui == NULL)
-	continue;
-
-      thread = inferior_thread ();
-      if (should_print_stop_to_console (interp, thread))
-	print_stop_event (tui->interp_ui_out ());
-    }
-}
-
-/* Observer for the signal_received notification.  */
-
-static void
-tui_on_signal_received (enum gdb_signal siggnal)
-{
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      print_signal_received_reason (tui->interp_ui_out (), siggnal);
-    }
-}
-
-/* Observer for the end_stepping_range notification.  */
-
-static void
-tui_on_end_stepping_range (void)
-{
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      print_end_stepping_range_reason (tui->interp_ui_out ());
-    }
-}
-
-/* Observer for the signal_exited notification.  */
-
-static void
-tui_on_signal_exited (enum gdb_signal siggnal)
-{
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      print_signal_exited_reason (tui->interp_ui_out (), siggnal);
-    }
-}
-
-/* Observer for the exited notification.  */
-
-static void
-tui_on_exited (int exitstatus)
-{
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      print_exited_reason (tui->interp_ui_out (), exitstatus);
-    }
-}
-
-/* Observer for the no_history notification.  */
-
-static void
-tui_on_no_history (void)
-{
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      print_no_history_reason (tui->interp_ui_out ());
-    }
-}
-
-/* Observer for the sync_execution_done notification.  */
-
-static void
-tui_on_sync_execution_done (void)
-{
-  struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-  if (tui == NULL)
-    return;
-
-  display_gdb_prompt (NULL);
-}
-
-/* Observer for the command_error notification.  */
-
-static void
-tui_on_command_error (void)
-{
-  struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-  if (tui == NULL)
-    return;
-
-  display_gdb_prompt (NULL);
-}
-
-/* Observer for the user_selected_context_changed notification.  */
-
-static void
-tui_on_user_selected_context_changed (user_selected_what selection)
-{
-  /* This event is suppressed.  */
-  if (cli_suppress_notification.user_selected_context)
-    return;
-
-  thread_info *tp = inferior_ptid != null_ptid ? inferior_thread () : NULL;
-
-  SWITCH_THRU_ALL_UIS ()
-    {
-      struct interp *tui = as_tui_interp (top_level_interpreter ());
-
-      if (tui == NULL)
-	continue;
-
-      if (selection & USER_SELECTED_INFERIOR)
-	print_selected_inferior (tui->interp_ui_out ());
-
-      if (tp != NULL
-	  && ((selection & (USER_SELECTED_THREAD | USER_SELECTED_FRAME))))
-	print_selected_thread_frame (tui->interp_ui_out (), selection);
-
-    }
-}
-
 /* These implement the TUI interpreter.  */
 
 void
@@ -349,17 +175,7 @@ _initialize_tui_interp ()
   if (interpreter_p == INTERP_CONSOLE)
     interpreter_p = INTERP_TUI;
 
-  /* If changing this, remember to update cli-interp.c as well.  */
-  gdb::observers::normal_stop.attach (tui_on_normal_stop, "tui-interp");
-  gdb::observers::signal_received.attach (tui_on_signal_received, "tui-interp");
-  gdb::observers::end_stepping_range.attach (tui_on_end_stepping_range,
-					     "tui-interp");
-  gdb::observers::signal_exited.attach (tui_on_signal_exited, "tui-interp");
-  gdb::observers::exited.attach (tui_on_exited, "tui-interp");
-  gdb::observers::no_history.attach (tui_on_no_history, "tui-interp");
-  gdb::observers::sync_execution_done.attach (tui_on_sync_execution_done,
-					      "tui-interp");
-  gdb::observers::command_error.attach (tui_on_command_error, "tui-interp");
-  gdb::observers::user_selected_context_changed.attach
-    (tui_on_user_selected_context_changed, "tui-interp");
+  /* There are no observers here because the CLI interpreter's
+     observers work for the TUI interpreter as well.  See
+     cli-interp.c.  */
 }