Introduce async-event.[ch]

This patch splits out some gdb-specific code from event-loop, into new
files async-event.[ch].  Strictly speaking this code could perhaps be
put into gdbsupport/, but because gdbserver does not currently use it,
it seemed better, for size reasons, to split it out.

gdb/ChangeLog
2020-04-13  Tom Tromey  <tom@tromey.com>

	* tui/tui-win.c: Include async-event.h.
	* remote.c: Include async-event.h.
	* remote-notif.c: Include async-event.h.
	* record-full.c: Include async-event.h.
	* record-btrace.c: Include async-event.h.
	* infrun.c: Include async-event.h.
	* event-top.c: Include async-event.h.
	* event-loop.h: Move some declarations to async-event.h.
	* event-loop.c: Don't include ser-event.h or top.h.  Move some
	code to async-event.c.
	* async-event.h: New file.
	* async-event.c: New file.
	* Makefile.in (COMMON_SFILES): Add async-event.c.
	(HFILES_NO_SRCDIR): Add async-event.h.

1 files changed, 71 insertions, 0 deletions

diff --git a/gdb/async-event.h b/gdb/async-event.h
new file mode 100644
index 0000000..408f776
--- /dev/null
+++ b/gdb/async-event.h
@@ -0,0 +1,71 @@
+/* Async events for the GDB event loop.
+   Copyright (C) 1999-2019 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef ASYNC_EVENT_H
+#define ASYNC_EVENT_H
+
+#include "event-loop.h"
+
+struct async_signal_handler;
+struct async_event_handler;
+typedef void (sig_handler_func) (gdb_client_data);
+typedef void (async_event_handler_func) (gdb_client_data);
+
+extern struct async_signal_handler *
+  create_async_signal_handler (sig_handler_func *proc, 
+			       gdb_client_data client_data);
+extern void delete_async_signal_handler (struct async_signal_handler **);
+
+/* Call the handler from HANDLER the next time through the event
+   loop.  */
+extern void mark_async_signal_handler (struct async_signal_handler *handler);
+
+/* Returns true if HANDLER is marked ready.  */
+
+extern int
+  async_signal_handler_is_marked (struct async_signal_handler *handler);
+
+/* Mark HANDLER as NOT ready.  */
+
+extern void clear_async_signal_handler (struct async_signal_handler *handler);
+
+/* Create and register an asynchronous event source in the event loop,
+   and set PROC as its callback.  CLIENT_DATA is passed as argument to
+   PROC upon its invocation.  Returns a pointer to an opaque structure
+   used to mark as ready and to later delete this event source from
+   the event loop.  */
+extern struct async_event_handler *
+  create_async_event_handler (async_event_handler_func *proc,
+			      gdb_client_data client_data);
+
+/* Remove the event source pointed by HANDLER_PTR created by
+   CREATE_ASYNC_EVENT_HANDLER from the event loop, and release it.  */
+extern void
+  delete_async_event_handler (struct async_event_handler **handler_ptr);
+
+/* Call the handler from HANDLER the next time through the event
+   loop.  */
+extern void mark_async_event_handler (struct async_event_handler *handler);
+
+/* Mark the handler (ASYNC_HANDLER_PTR) as NOT ready.  */
+
+extern void clear_async_event_handler (struct async_event_handler *handler);
+
+extern void initialize_async_signal_handlers (void);
+
+#endif /* ASYNC_EVENT_H */