[binutils-gdb] gdb: introduce a per-interpreter event servicing method

[Patrick Monnerat]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=568ec5b9831b0d6abc7aff4e76cefcc0fa7e0c5e

commit 568ec5b9831b0d6abc7aff4e76cefcc0fa7e0c5e
Author: Patrick Monnerat <patrick@monnerat.net>
Date:   Fri May 30 19:16:56 2025 +0200

    gdb: introduce a per-interpreter event servicing method
    
    This allows an interpreter to override internal calls to
    gdb_do_one_event in case the former needs to handle alternate event
    sources.
    
    The default action is to call gdb_do_one_event and this is not overriden
    in current internal interpreters. However this feature allows to easily
    embed Tcl/Tk in insight that needs to concurrently handle Tcl events for
    GUI handling.
    
    In all cases, an interpreter event servicing method must call
    gdb_do_one_event at some point.
    
    All internal event servicing calls from gdb now direct to the
    interpreter-specific method rather than gdb_do_one_event itself.

Diff:
---
 gdb/interps.h | 8 ++++++++
 gdb/main.c    | 2 +-
 gdb/top.c     | 4 ++--
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/gdb/interps.h b/gdb/interps.h
index 8d35309f686..c74495bce18 100644
--- a/gdb/interps.h
+++ b/gdb/interps.h
@@ -23,6 +23,7 @@
 #define GDB_INTERPS_H
 
 #include "gdbsupport/intrusive_list.h"
+#include "gdbsupport/event-loop.h"
 
 struct bpstat;
 struct ui_out;
@@ -78,6 +79,13 @@ public:
   virtual void pre_command_loop ()
   {}
 
+  /* Service one event.
+     This gives the interpreter a chance to handle its own private
+     events that cannot be fed into the gdb event mechanism.
+     In all cases, this should call gdb_do_one_event at some point.  */
+  virtual int do_one_event (int mstimeout = -1)
+  { return gdb_do_one_event (mstimeout); }
+
   /* Returns true if this interpreter supports using the readline
      library; false if it uses GDB's own simplified readline
      emulation.  */
diff --git a/gdb/main.c b/gdb/main.c
index 2dcb67d7ce8..1806ca0310d 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -399,7 +399,7 @@ start_event_loop ()
 
       try
 	{
-	  result = gdb_do_one_event ();
+	  result = current_interpreter ()->do_one_event ();
 	}
       catch (const gdb_exception_forced_quit &ex)
 	{
diff --git a/gdb/top.c b/gdb/top.c
index 6adef467b90..25a2afe09c8 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -415,7 +415,7 @@ wait_sync_command_done (void)
      point.  */
   scoped_enable_commit_resumed enable ("sync wait");
 
-  while (gdb_do_one_event () >= 0)
+  while (current_interpreter ()->do_one_event () >= 0)
     if (ui->prompt_state != PROMPT_BLOCKED)
       break;
 }
@@ -1031,7 +1031,7 @@ gdb_readline_wrapper (const char *prompt)
     (*after_char_processing_hook) ();
   gdb_assert (after_char_processing_hook == NULL);
 
-  while (gdb_do_one_event () >= 0)
+  while (current_interpreter ()->do_one_event () >= 0)
     if (gdb_readline_wrapper_done)
       break;