[PATCH 10/30] Make Python use a struct serial event

Pedro Alves
2016-03-18T19:26:35Z

From: Pedro Alves <pedro@cascais.lan>

Now that we have an abstract for wakeable events, use it instead of a
(heavier) serial pipe.

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

* python/python.c: Include "ser-event.h".
(gdbpy_event_fds): Delete.
(gdbpy_serial_event): New.
(gdbpy_run_events): Change prototype. Use serial_event_clear
instead of serial_readchar.
(gdbpy_post_event): Use serial_event_set instead of serial_write.
(gdbpy_initialize_events): Use make_serial_event instead of
serial_pipe.
---
gdb/python/python.c | 33 ++++++++++++++-------------------
1 file changed, 14 insertions(+), 19 deletions(-)

diff --git a/gdb/python/python.c b/gdb/python/python.c
index 7202105..ab3aa0a 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -35,6 +35,7 @@
#include "cli/cli-utils.h"
#include <ctype.h>
#include "location.h"
+#include "ser-event.h"

/* Declared constants and enum for python stack printing. */
static const char python_excp_none[] = "none";
@@ -922,26 +923,25 @@ static struct gdbpy_event *gdbpy_event_list;
/* The final link of the event list. */
static struct gdbpy_event **gdbpy_event_list_end;

-/* We use a file handler, and not an async handler, so that we can
- wake up the main thread even when it is blocked in poll(). */
-static struct serial *gdbpy_event_fds[2];
+/* So that we can wake up the main thread even when it is blocked in
+ poll(). */
+static struct serial_event *gdbpy_serial_event;

/* The file handler callback. This reads from the internal pipe, and
then processes the Python event queue. This will always be run in
the main gdb thread. */

static void
-gdbpy_run_events (struct serial *scb, void *context)
+gdbpy_run_events (int error, gdb_client_data client_data)
{
struct cleanup *cleanup;

cleanup = ensure_python_env (get_current_arch (), current_language);

- /* Flush the fd. Do this before flushing the events list, so that
- any new event post afterwards is sure to re-awake the event
+ /* Clear the event fd. Do this before flushing the events list, so
+ that any new event post afterwards is sure to re-awake the event
loop. */
- while (serial_readchar (gdbpy_event_fds[0], 0) >= 0)
- ;
+ serial_event_clear (gdbpy_serial_event);

while (gdbpy_event_list)
{
@@ -999,12 +999,7 @@ gdbpy_post_event (PyObject *self, PyObject *args)

/* Wake up gdb when needed. */
if (wakeup)
- {
- char c = 'q'; /* Anything. */
-
- if (serial_write (gdbpy_event_fds[1], &c, 1))
- return PyErr_SetFromErrno (PyExc_IOError);
- }
+ serial_event_set (gdbpy_serial_event);

Py_RETURN_NONE;
}
@@ -1013,11 +1008,11 @@ gdbpy_post_event (PyObject *self, PyObject *args)
static int
gdbpy_initialize_events (void)
{
- if (serial_pipe (gdbpy_event_fds) == 0)
- {
- gdbpy_event_list_end = &gdbpy_event_list;
- serial_async (gdbpy_event_fds[0], gdbpy_run_events, NULL);
- }
+ gdbpy_event_list_end = &gdbpy_event_list;
+
+ gdbpy_serial_event = make_serial_event ();
+ add_file_handler (serial_event_fd (gdbpy_serial_event),
+ gdbpy_run_events, NULL);

return 0;
}
--
2.5.0