blob: 83fef504fb525dd7222c1e814b63108ff3b2cff0 [file] [log] [blame]
/* GIO - GLib Input, Output and Streaming Library
*
* Copyright 2022 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "gmemorymonitor.h"
#include "gioerror.h"
#include "ginitable.h"
#include "giomodule-priv.h"
#include "glibintl.h"
#include "glib/gstdio.h"
#include "gcancellable.h"
#include <windows.h>
#define G_TYPE_MEMORY_MONITOR_WIN32 (g_memory_monitor_win32_get_type ())
G_DECLARE_FINAL_TYPE (GMemoryMonitorWin32, g_memory_monitor_win32, G, MEMORY_MONITOR_WIN32, GObject)
#define G_MEMORY_MONITOR_WIN32_GET_INITABLE_IFACE(o) (G_TYPE_INSTANCE_GET_INTERFACE ((o), G_TYPE_INITABLE, GInitable))
static void g_memory_monitor_win32_iface_init (GMemoryMonitorInterface *iface);
static void g_memory_monitor_win32_initable_iface_init (GInitableIface *iface);
struct _GMemoryMonitorWin32
{
GObject parent_instance;
HANDLE event;
HANDLE mem;
HANDLE thread;
};
G_DEFINE_TYPE_WITH_CODE (GMemoryMonitorWin32, g_memory_monitor_win32, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE,
g_memory_monitor_win32_initable_iface_init)
G_IMPLEMENT_INTERFACE (G_TYPE_MEMORY_MONITOR,
g_memory_monitor_win32_iface_init)
_g_io_modules_ensure_extension_points_registered ();
g_io_extension_point_implement (G_MEMORY_MONITOR_EXTENSION_POINT_NAME,
g_define_type_id,
"win32",
30))
static void
g_memory_monitor_win32_init (GMemoryMonitorWin32 *win32)
{
}
static gboolean
watch_handler (gpointer user_data)
{
GMemoryMonitorWin32 *win32 = user_data;
g_signal_emit_by_name (win32, "low-memory-warning",
G_MEMORY_MONITOR_WARNING_LEVEL_LOW);
return G_SOURCE_REMOVE;
}
/* Thread which watches for win32 memory resource events */
static DWORD WINAPI
watch_thread_function (LPVOID parameter)
{
GWeakRef *weak_ref = parameter;
GMemoryMonitorWin32 *win32 = NULL;
HANDLE handles[2] = { 0, };
DWORD result;
BOOL low_memory_state;
win32 = g_weak_ref_get (weak_ref);
if (!win32)
goto end;
if (!DuplicateHandle (GetCurrentProcess (),
win32->event,
GetCurrentProcess (),
&handles[0],
0,
FALSE,
DUPLICATE_SAME_ACCESS))
{
gchar *emsg;
emsg = g_win32_error_message (GetLastError ());
g_debug ("DuplicateHandle failed: %s", emsg);
g_free (emsg);
goto end;
}
if (!DuplicateHandle (GetCurrentProcess (),
win32->mem,
GetCurrentProcess (),
&handles[1],
0,
FALSE,
DUPLICATE_SAME_ACCESS))
{
gchar *emsg;
emsg = g_win32_error_message (GetLastError ());
g_debug ("DuplicateHandle failed: %s", emsg);
g_free (emsg);
goto end;
}
g_clear_object (&win32);
while (1)
{
if (!QueryMemoryResourceNotification (handles[1], &low_memory_state))
{
gchar *emsg;
emsg = g_win32_error_message (GetLastError ());
g_debug ("QueryMemoryResourceNotification failed: %s", emsg);
g_free (emsg);
break;
}
win32 = g_weak_ref_get (weak_ref);
if (!win32)
break;
if (low_memory_state)
{
g_idle_add_full (G_PRIORITY_DEFAULT,
watch_handler,
g_steal_pointer (&win32),
g_object_unref);
/* throttle a bit the loop */
g_usleep (G_USEC_PER_SEC);
continue;
}
g_clear_object (&win32);
result = WaitForMultipleObjects (G_N_ELEMENTS (handles), handles, FALSE, INFINITE);
switch (result)
{
case WAIT_OBJECT_0 + 1:
continue;
case WAIT_FAILED:
{
gchar *emsg;
emsg = g_win32_error_message (GetLastError ());
g_debug ("WaitForMultipleObjects failed: %s", emsg);
g_free (emsg);
}
G_GNUC_FALLTHROUGH;
default:
goto end;
}
}
end:
if (handles[0])
CloseHandle (handles[0]);
if (handles[1])
CloseHandle (handles[1]);
g_clear_object (&win32);
g_weak_ref_clear (weak_ref);
g_free (weak_ref);
return 0;
}
static gboolean
g_memory_monitor_win32_initable_init (GInitable *initable,
GCancellable *cancellable,
GError **error)
{
GMemoryMonitorWin32 *win32 = G_MEMORY_MONITOR_WIN32 (initable);
GWeakRef *weak_ref = NULL;
win32->event = CreateEvent (NULL, FALSE, FALSE, NULL);
if (win32->event == NULL)
{
g_set_error_literal (error, G_IO_ERROR, g_io_error_from_errno (GetLastError ()),
"Failed to create event");
return FALSE;
}
win32->mem = CreateMemoryResourceNotification (LowMemoryResourceNotification);
if (win32->mem == NULL)
{
g_set_error_literal (error, G_IO_ERROR, g_io_error_from_errno (GetLastError ()),
"Failed to create resource notification handle");
return FALSE;
}
weak_ref = g_new0 (GWeakRef, 1);
g_weak_ref_init (weak_ref, win32);
/* Use CreateThread (not GThread) with a small stack to make it more lightweight. */
win32->thread = CreateThread (NULL, 1024, watch_thread_function, weak_ref, 0, NULL);
if (win32->thread == NULL)
{
g_set_error_literal (error, G_IO_ERROR, g_io_error_from_errno (GetLastError ()),
"Failed to create memory resource notification thread");
g_weak_ref_clear (weak_ref);
g_free (weak_ref);
return FALSE;
}
return TRUE;
}
static void
g_memory_monitor_win32_finalize (GObject *object)
{
GMemoryMonitorWin32 *win32 = G_MEMORY_MONITOR_WIN32 (object);
if (win32->thread)
{
SetEvent (win32->event);
WaitForSingleObject (win32->thread, INFINITE);
CloseHandle (win32->thread);
}
if (win32->event)
CloseHandle (win32->event);
if (win32->mem)
CloseHandle (win32->mem);
G_OBJECT_CLASS (g_memory_monitor_win32_parent_class)->finalize (object);
}
static void
g_memory_monitor_win32_class_init (GMemoryMonitorWin32Class *nl_class)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (nl_class);
gobject_class->finalize = g_memory_monitor_win32_finalize;
}
static void
g_memory_monitor_win32_iface_init (GMemoryMonitorInterface *monitor_iface)
{
}
static void
g_memory_monitor_win32_initable_iface_init (GInitableIface *iface)
{
iface->init = g_memory_monitor_win32_initable_init;
}