mutter/cogl/cogl-renderer.c
Neil Roberts d259a87602 Don't use the 'NULL' GModule to resolve GL symbols
Previously, _cogl_get_proc_address had a fallback to resolve the
symbol using g_module_open(NULL) to get the symbol from anywhere in
the address space. The EGL backend ends up using this on some drivers
because eglGetProcAddress isn't meant to return a pointer for core
functions. This causes problems if something in the process is linking
against a different GL library, for example Cairo may be linking
against libGL itself. In this case it may end up resolving symbols
from the GL library even if GLES is being used.

This patch removes the fallback. The EGL version now has its own
fallback instead which passes the existing libgl_module from the
renderer to g_module_symbol so that it should only get symbols from
that library or its dependency chain. The GLX and WGL winsys only call
glXGetProcAddress and wglGetProcAddress. The stub winsys does however
continue using the global symbol lookup.

The internal _cogl_get_proc_address function has been renamed to
_cogl_renderer_get_proc_address because it needs a connected renderer
to work so it could be considered to be a renderer method. The pointer
to the renderer is passed down to the winsys backends so that it can
use the data attached to the renderer to get the module pointers.

https://bugzilla.gnome.org/show_bug.cgi?id=655412

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-07-27 16:10:02 +01:00

391 lines
9.9 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2011 Intel Corporation.
*
* 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 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-private.h"
#include "cogl-object.h"
#include "cogl-renderer.h"
#include "cogl-renderer-private.h"
#include "cogl-display-private.h"
#include "cogl-winsys-private.h"
#include "cogl-winsys-stub-private.h"
#include "cogl-winsys-egl-private.h"
#ifdef COGL_HAS_GLX_SUPPORT
extern const CoglWinsysVtable *_cogl_winsys_glx_get_vtable (void);
#endif
#ifdef COGL_HAS_WGL_SUPPORT
extern const CoglWinsysVtable *_cogl_winsys_wgl_get_vtable (void);
#endif
typedef const CoglWinsysVtable *(*CoglWinsysVtableGetter) (void);
static CoglWinsysVtableGetter _cogl_winsys_vtable_getters[] =
{
#ifdef COGL_HAS_GLX_SUPPORT
_cogl_winsys_glx_get_vtable,
#endif
#ifdef COGL_HAS_EGL_SUPPORT
_cogl_winsys_egl_get_vtable,
#endif
#ifdef COGL_HAS_WGL_SUPPORT
_cogl_winsys_wgl_get_vtable,
#endif
_cogl_winsys_stub_get_vtable,
};
static void _cogl_renderer_free (CoglRenderer *renderer);
COGL_OBJECT_DEFINE (Renderer, renderer);
typedef struct _CoglNativeFilterClosure
{
CoglNativeFilterFunc func;
void *data;
} CoglNativeFilterClosure;
GQuark
cogl_renderer_error_quark (void)
{
return g_quark_from_static_string ("cogl-renderer-error-quark");
}
static const CoglWinsysVtable *
_cogl_renderer_get_winsys (CoglRenderer *renderer)
{
return renderer->winsys_vtable;
}
static void
native_filter_closure_free (CoglNativeFilterClosure *closure)
{
g_slice_free (CoglNativeFilterClosure, closure);
}
static void
_cogl_renderer_free (CoglRenderer *renderer)
{
const CoglWinsysVtable *winsys = _cogl_renderer_get_winsys (renderer);
winsys->renderer_disconnect (renderer);
#ifndef HAVE_DIRECTLY_LINKED_GL_LIBRARY
if (renderer->libgl_module)
g_module_close (renderer->libgl_module);
#endif
g_slist_foreach (renderer->event_filters,
(GFunc) native_filter_closure_free,
NULL);
g_slist_free (renderer->event_filters);
g_free (renderer);
}
CoglRenderer *
cogl_renderer_new (void)
{
CoglRenderer *renderer = g_new0 (CoglRenderer, 1);
_cogl_init ();
renderer->connected = FALSE;
renderer->event_filters = NULL;
return _cogl_renderer_object_new (renderer);
}
#if COGL_HAS_XLIB_SUPPORT
void
cogl_xlib_renderer_set_foreign_display (CoglRenderer *renderer,
Display *xdisplay)
{
g_return_if_fail (cogl_is_renderer (renderer));
/* NB: Renderers are considered immutable once connected */
g_return_if_fail (!renderer->connected);
renderer->foreign_xdpy = xdisplay;
}
Display *
cogl_xlib_renderer_get_foreign_display (CoglRenderer *renderer)
{
g_return_val_if_fail (cogl_is_renderer (renderer), NULL);
return renderer->foreign_xdpy;
}
#endif /* COGL_HAS_XLIB_SUPPORT */
gboolean
cogl_renderer_check_onscreen_template (CoglRenderer *renderer,
CoglOnscreenTemplate *onscreen_template,
GError **error)
{
CoglDisplay *display;
const CoglWinsysVtable *winsys = _cogl_renderer_get_winsys (renderer);
if (!winsys->renderer_connect (renderer, error))
return FALSE;
display = cogl_display_new (renderer, onscreen_template);
if (!cogl_display_setup (display, error))
{
cogl_object_unref (display);
return FALSE;
}
cogl_object_unref (display);
return TRUE;
}
static gboolean
_cogl_renderer_choose_driver (CoglRenderer *renderer,
GError **error)
{
const char *driver_name = g_getenv ("COGL_DRIVER");
const char *libgl_name;
#ifdef HAVE_COGL_GL
if (driver_name == NULL || !strcmp (driver_name, "gl"))
{
renderer->driver = COGL_DRIVER_GL;
libgl_name = COGL_GL_LIBNAME;
goto found;
}
#endif
#ifdef HAVE_COGL_GLES2
if (driver_name == NULL || !strcmp (driver_name, "gles2"))
{
renderer->driver = COGL_DRIVER_GLES2;
libgl_name = COGL_GLES2_LIBNAME;
goto found;
}
#endif
#ifdef HAVE_COGL_GLES
if (driver_name == NULL || !strcmp (driver_name, "gles1"))
{
renderer->driver = COGL_DRIVER_GLES1;
libgl_name = COGL_GLES1_LIBNAME;
goto found;
}
#endif
g_set_error (error,
COGL_DRIVER_ERROR,
COGL_DRIVER_ERROR_NO_SUITABLE_DRIVER_FOUND,
"No suitable driver found");
return FALSE;
found:
#ifndef HAVE_DIRECTLY_LINKED_GL_LIBRARY
renderer->libgl_module = g_module_open (libgl_name,
G_MODULE_BIND_LAZY);
if (renderer->libgl_module == NULL)
{
g_set_error (error, COGL_DRIVER_ERROR,
COGL_DRIVER_ERROR_FAILED_TO_LOAD_LIBRARY,
"Failed to dynamically open the GL library \"%s\"",
libgl_name);
return FALSE;
}
#endif /* HAVE_DIRECTLY_LINKED_GL_LIBRARY */
return TRUE;
}
/* Final connection API */
gboolean
cogl_renderer_connect (CoglRenderer *renderer, GError **error)
{
int i;
GString *error_message;
if (renderer->connected)
return TRUE;
/* The driver needs to be chosen before connecting the renderer
because eglInitialize requires the library containing the GL API
to be loaded before its called */
if (!_cogl_renderer_choose_driver (renderer, error))
return FALSE;
error_message = g_string_new ("");
for (i = 0; i < G_N_ELEMENTS (_cogl_winsys_vtable_getters); i++)
{
const CoglWinsysVtable *winsys = _cogl_winsys_vtable_getters[i]();
GError *tmp_error = NULL;
if (renderer->winsys_id_override != COGL_WINSYS_ID_ANY)
{
if (renderer->winsys_id_override != winsys->id)
continue;
}
else
{
char *user_choice = getenv ("COGL_RENDERER");
if (user_choice && strcmp (winsys->name, user_choice) != 0)
continue;
}
/* At least temporarily we will associate this winsys with
* the renderer in-case ->renderer_connect calls API that
* wants to query the current winsys... */
renderer->winsys_vtable = winsys;
if (!winsys->renderer_connect (renderer, &tmp_error))
{
g_string_append_c (error_message, '\n');
g_string_append (error_message, tmp_error->message);
g_error_free (tmp_error);
}
else
{
renderer->connected = TRUE;
g_string_free (error_message, TRUE);
return TRUE;
}
}
if (!renderer->connected)
{
renderer->winsys_vtable = NULL;
g_set_error (error, COGL_WINSYS_ERROR,
COGL_WINSYS_ERROR_INIT,
"Failed to connected to any renderer: %s",
error_message->str);
g_string_free (error_message, TRUE);
return FALSE;
}
return TRUE;
}
CoglFilterReturn
_cogl_renderer_handle_native_event (CoglRenderer *renderer,
void *event)
{
GSList *l, *next;
/* Pass the event on to all of the registered filters in turn */
for (l = renderer->event_filters; l; l = next)
{
CoglNativeFilterClosure *closure = l->data;
/* The next pointer is taken now so that we can handle the
closure being removed during emission */
next = l->next;
if (closure->func (event, closure->data) == COGL_FILTER_REMOVE)
return COGL_FILTER_REMOVE;
}
/* If the backend for the renderer also wants to see the events, it
should just register its own filter */
return COGL_FILTER_CONTINUE;
}
void
_cogl_renderer_add_native_filter (CoglRenderer *renderer,
CoglNativeFilterFunc func,
void *data)
{
CoglNativeFilterClosure *closure;
closure = g_slice_new (CoglNativeFilterClosure);
closure->func = func;
closure->data = data;
renderer->event_filters = g_slist_prepend (renderer->event_filters, closure);
}
void
_cogl_renderer_remove_native_filter (CoglRenderer *renderer,
CoglNativeFilterFunc func,
void *data)
{
GSList *l, *prev = NULL;
for (l = renderer->event_filters; l; prev = l, l = l->next)
{
CoglNativeFilterClosure *closure = l->data;
if (closure->func == func && closure->data == data)
{
native_filter_closure_free (closure);
if (prev)
prev->next = g_slist_delete_link (prev->next, l);
else
renderer->event_filters =
g_slist_delete_link (renderer->event_filters, l);
break;
}
}
}
void
cogl_renderer_set_winsys_id (CoglRenderer *renderer,
CoglWinsysID winsys_id)
{
g_return_if_fail (!renderer->connected);
renderer->winsys_id_override = winsys_id;
}
CoglWinsysID
cogl_renderer_get_winsys_id (CoglRenderer *renderer)
{
g_return_val_if_fail (renderer->connected, 0);
return renderer->winsys_vtable->id;
}
void *
_cogl_renderer_get_proc_address (CoglRenderer *renderer,
const char *name)
{
const CoglWinsysVtable *winsys = _cogl_renderer_get_winsys (renderer);
return winsys->renderer_get_proc_address (renderer, name);
}