kms: Adds api to get at the kms file descriptor

This adds a cogl_kms_renderer_get_kms_fd() function that lets developers
access the kms file descriptor being used for controlling the kernel
mode setting.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

cogl/Makefile.am

@@ -397,6 +397,8 @@ cogl_sources_c += \
 	$(srcdir)/winsys/cogl-winsys-egl-wayland-private.h
 endif
 if SUPPORT_EGL_PLATFORM_KMS
+cogl_public_h += \
+	$(srcdir)/cogl-kms-renderer.h
 cogl_sources_c += \
 	$(srcdir)/winsys/cogl-winsys-egl-kms.c \
 	$(srcdir)/winsys/cogl-winsys-egl-kms-private.h

cogl/cogl-kms-renderer.h

@@ -0,0 +1,51 @@
+/*
+ * 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.
+ */
+
+#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
+#error "Only <cogl/cogl.h> can be included directly."
+#endif
+
+#ifndef __COGL_KMS_RENDERER_H__
+#define __COGL_KMS_RENDERER_H__
+
+#include <cogl/cogl-types.h>
+#include <cogl/cogl-renderer.h>
+
+G_BEGIN_DECLS
+
+/**
+ * cogl_kms_renderer_get_kms_fd:
+ * @renderer: A #CoglRenderer
+ *
+ * Queries the file descriptor Cogl is using internally for
+ * communicating with the kms driver.
+ *
+ * Return value: The kms file descriptor or -1 if no kms file
+ *               desriptor has been opened by Cogl.
+ * Stability: unstable
+ */
+int
+cogl_kms_renderer_get_kms_fd (CoglRenderer *renderer);
+
+G_END_DECLS
+#endif /* __COGL_KMS_RENDERER_H__ */

cogl/cogl.h

@@ -98,6 +98,9 @@ typedef struct _CoglFramebuffer CoglFramebuffer;
 #include <cogl/cogl-framebuffer.h>
 #include <cogl/cogl-onscreen.h>
 #include <cogl/cogl-poll.h>
+#if defined (COGL_HAS_EGL_PLATFORM_KMS_SUPPORT)
+#include <cogl/cogl-kms-renderer.h>
+#endif
 #if defined (COGL_HAS_EGL_PLATFORM_WAYLAND_SUPPORT)
 #include <cogl/cogl-wayland-renderer.h>
 #endif

cogl/winsys/cogl-winsys-egl-kms.c

@@ -565,3 +565,18 @@ _cogl_winsys_egl_kms_get_vtable (void)
 
   return &vtable;
 }
+
+int
+cogl_kms_renderer_get_kms_fd (CoglRenderer *renderer)
+{
+  _COGL_RETURN_VAL_IF_FAIL (cogl_is_renderer (renderer), -1);
+
+  if (renderer->connected)
+    {
+      CoglRendererEGL *egl_renderer = renderer->winsys;
+      CoglRendererKMS *kms_renderer = egl_renderer->platform;
+      return kms_renderer->fd;
+    }
+  else
+    return -1;
+}