[PATCH v3 08/34] Always run async signal handlers in the main UI

[Pedro Alves <palves at redhat dot com>]

Async signal handlers have no connection to whichever was the current
UI, and thus always run on the main one.

gdb/ChangeLog:
yyyy-mm-dd  Pedro Alves  <palves@redhat.com>

	* event-loop.c: Include top.h.
	(invoke_async_signal_handlers): Switch to the main UI.
	* event-top.c (main_ui_): Update comment.
	(main_ui): New global.
	* top.h (main_ui): Declare.
---
 gdb/event-loop.c | 4 ++++
 gdb/event-top.c  | 5 ++---
 gdb/top.h        | 5 +++++
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/gdb/event-loop.c b/gdb/event-loop.c
index 60ef2a5..fe28305 100644
--- a/gdb/event-loop.c
+++ b/gdb/event-loop.c
@@ -35,6 +35,7 @@
 #include "gdb_sys_time.h"
 #include "gdb_select.h"
 #include "observer.h"
+#include "top.h"
 
 /* Tell create_file_handler what events we are interested in.
    This is used by the select version of the event loop.  */
@@ -967,6 +968,9 @@ invoke_async_signal_handlers (void)
 	break;
       any_ready = 1;
       async_handler_ptr->ready = 0;
+      /* Async signal handlers have no connection to whichever was the
+	 current UI, and thus always run on the main one.  */
+      current_ui = main_ui;
       (*async_handler_ptr->proc) (async_handler_ptr->client_data);
     }
 
diff --git a/gdb/event-top.c b/gdb/event-top.c
index c6e3b7e..63f6896 100644
--- a/gdb/event-top.c
+++ b/gdb/event-top.c
@@ -437,11 +437,10 @@ top_level_prompt (void)
   return xstrdup (prompt);
 }
 
-/* The main UI.  This is the UI that is bound to stdin/stdout/stderr.
-   It always exists and is created automatically when GDB starts
-   up.  */
+/* The main UI.  */
 static struct ui main_ui_;
 
+struct ui *main_ui = &main_ui_;
 struct ui *current_ui = &main_ui_;
 struct ui *ui_list = &main_ui_;
 
diff --git a/gdb/top.h b/gdb/top.h
index 805022f..8f01f78 100644
--- a/gdb/top.h
+++ b/gdb/top.h
@@ -86,6 +86,11 @@ struct ui
   struct ui_file *m_gdb_stdlog;
 };
 
+/* The main UI.  This is the UI that is bound to stdin/stdout/stderr.
+   It always exists and is created automatically when GDB starts
+   up.  */
+extern struct ui *main_ui;
+
 /* The current UI.  */
 extern struct ui *current_ui;
 
-- 
2.5.5