/* Host support routines for MinGW, for GDB, the GNU debugger.
- Copyright (C) 2006
- Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008 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 2 of the License, or
+ 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,
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, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "serial.h"
+#include "event-loop.h"
#include "gdb_assert.h"
#include "gdb_select.h"
#include "gdb_string.h"
+#include "readline/readline.h"
#include <windows.h>
+/* This event is signalled whenever an asynchronous SIGINT handler
+ needs to perform an action in the main thread. */
+static HANDLE sigint_event;
+
+/* When SIGINT_EVENT is signalled, gdb_select will call this
+ function. */
+struct async_signal_handler *sigint_handler;
+
/* The strerror() function can return NULL for errno values that are
out of range. Provide a "safe" version that always returns a
printable string.
HANDLE h;
DWORD event;
DWORD num_handles;
+ /* SCBS contains serial control objects corresponding to file
+ descriptors in READFDS and WRITEFDS. */
+ struct serial *scbs[MAXIMUM_WAIT_OBJECTS];
+ /* The number of valid entries in SCBS. */
+ size_t num_scbs;
int fd;
int num_ready;
- int indx;
+ size_t indx;
num_ready = 0;
num_handles = 0;
+ num_scbs = 0;
for (fd = 0; fd < n; ++fd)
{
HANDLE read = NULL, except = NULL;
if something starts using it. */
gdb_assert (!writefds || !FD_ISSET (fd, writefds));
- if (!FD_ISSET (fd, readfds)
- && !FD_ISSET (fd, exceptfds))
+ if ((!readfds || !FD_ISSET (fd, readfds))
+ && (!exceptfds || !FD_ISSET (fd, exceptfds)))
continue;
- h = (HANDLE) _get_osfhandle (fd);
scb = serial_for_fd (fd);
if (scb)
- serial_wait_handle (scb, &read, &except);
+ {
+ serial_wait_handle (scb, &read, &except);
+ scbs[num_scbs++] = scb;
+ }
if (read == NULL)
- read = h;
+ read = (HANDLE) _get_osfhandle (fd);
if (except == NULL)
{
if (!never_handle)
except = never_handle;
}
- if (FD_ISSET (fd, readfds))
+ if (readfds && FD_ISSET (fd, readfds))
{
gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
handles[num_handles++] = read;
}
- if (FD_ISSET (fd, exceptfds))
+ if (exceptfds && FD_ISSET (fd, exceptfds))
{
gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
handles[num_handles++] = except;
}
}
- /* If we don't need to wait for any handles, we are done. */
- if (!num_handles)
- {
- if (timeout)
- Sleep (timeout->tv_sec * 1000 + timeout->tv_usec / 1000);
- return 0;
- }
+ gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
+ handles[num_handles++] = sigint_event;
event = WaitForMultipleObjects (num_handles,
handles,
mutexes, that should never occur. */
gdb_assert (!(WAIT_ABANDONED_0 <= event
&& event < WAIT_ABANDONED_0 + num_handles));
+ /* We no longer need the helper threads to check for activity. */
+ for (indx = 0; indx < num_scbs; ++indx)
+ serial_done_wait_handle (scbs[indx]);
if (event == WAIT_FAILED)
return -1;
if (event == WAIT_TIMEOUT)
for (fd = 0, indx = 0; fd < n; ++fd)
{
HANDLE fd_h;
- struct serial *scb;
- if (!FD_ISSET (fd, readfds) && !FD_ISSET (fd, writefds))
+ if ((!readfds || !FD_ISSET (fd, readfds))
+ && (!exceptfds || !FD_ISSET (fd, exceptfds)))
continue;
- if (FD_ISSET (fd, readfds))
+ if (readfds && FD_ISSET (fd, readfds))
{
fd_h = handles[indx++];
/* This handle might be ready, even though it wasn't the handle
num_ready++;
}
- if (FD_ISSET (fd, exceptfds))
+ if (exceptfds && FD_ISSET (fd, exceptfds))
{
fd_h = handles[indx++];
/* This handle might be ready, even though it wasn't the handle
else
num_ready++;
}
+ }
- /* We created at least one event handle for this fd. Let the
- device know we are finished with it. */
- scb = serial_for_fd (fd);
- if (scb)
- serial_done_wait_handle (scb);
+ /* With multi-threaded SIGINT handling, there is a race between the
+ readline signal handler and GDB. It may still be in
+ rl_prep_terminal in another thread. Do not return until it is
+ done; we can check the state here because we never longjmp from
+ signal handlers on Windows. */
+ while (RL_ISSTATE (RL_STATE_SIGHANDLER))
+ Sleep (1);
+
+ if (h == sigint_event
+ || WaitForSingleObject (sigint_event, 0) == WAIT_OBJECT_0)
+ {
+ if (sigint_handler != NULL)
+ call_async_signal_handler (sigint_handler);
+
+ if (num_ready == 0)
+ {
+ errno = EINTR;
+ return -1;
+ }
}
return num_ready;
}
+
+/* Wrapper for the body of signal handlers. On Windows systems, a
+ SIGINT handler runs in its own thread. We can't longjmp from
+ there, and we shouldn't even prompt the user. Delay HANDLER
+ until the main thread is next in gdb_select. */
+
+void
+gdb_call_async_signal_handler (struct async_signal_handler *handler,
+ int immediate_p)
+{
+ if (immediate_p)
+ sigint_handler = handler;
+ else
+ {
+ mark_async_signal_handler (handler);
+ sigint_handler = NULL;
+ }
+ SetEvent (sigint_event);
+}
+
+void
+_initialize_mingw_hdep (void)
+{
+ sigint_event = CreateEvent (0, FALSE, FALSE, 0);
+}