Common: Add DRM display helper class and GBM GL context

CMakeModules/FindGBM.cmake

@@ -0,0 +1,70 @@
+# https://fossies.org/linux/misc/xbmc-18.9-Leia.tar.gz/xbmc-18.9-Leia/cmake/modules/FindGBM.cmake?m=t
+
+# FindGBM
+# ----------
+# Finds the GBM library
+#
+# This will define the following variables::
+#
+# GBM_FOUND - system has GBM
+# GBM_INCLUDE_DIRS - the GBM include directory
+# GBM_LIBRARIES - the GBM libraries
+# GBM_DEFINITIONS  - the GBM definitions
+#
+# and the following imported targets::
+#
+#   GBM::GBM   - The GBM library
+
+if(PKG_CONFIG_FOUND)
+  pkg_check_modules(PC_GBM gbm QUIET)
+endif()
+
+find_path(GBM_INCLUDE_DIR NAMES gbm.h
+                          PATHS ${PC_GBM_INCLUDEDIR})
+find_library(GBM_LIBRARY NAMES gbm
+                         PATHS ${PC_GBM_LIBDIR})
+
+set(GBM_VERSION ${PC_GBM_VERSION})
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(GBM
+                                  REQUIRED_VARS GBM_LIBRARY GBM_INCLUDE_DIR
+                                  VERSION_VAR GBM_VERSION)
+
+include(CheckCSourceCompiles)
+set(CMAKE_REQUIRED_LIBRARIES ${GBM_LIBRARY})
+check_c_source_compiles("#include <gbm.h>
+
+                         int main()
+                         {
+                           gbm_bo_map(NULL, 0, 0, 0, 0, GBM_BO_TRANSFER_WRITE, NULL, NULL);
+                         }
+                         " GBM_HAS_BO_MAP)
+
+check_c_source_compiles("#include <gbm.h>
+
+                         int main()
+                         {
+                           gbm_surface_create_with_modifiers(NULL, 0, 0, 0, NULL, 0);
+                         }
+                         " GBM_HAS_MODIFIERS)
+
+if(GBM_FOUND)
+  set(GBM_LIBRARIES ${GBM_LIBRARY})
+  set(GBM_INCLUDE_DIRS ${GBM_INCLUDE_DIR})
+  set(GBM_DEFINITIONS -DHAVE_GBM=1)
+  if(GBM_HAS_BO_MAP)
+    list(APPEND GBM_DEFINITIONS -DHAS_GBM_BO_MAP=1)
+  endif()
+  if(GBM_HAS_MODIFIERS)
+    list(APPEND GBM_DEFINITIONS -DHAS_GBM_MODIFIERS=1)
+  endif()
+  if(NOT TARGET GBM::GBM)
+    add_library(GBM::GBM UNKNOWN IMPORTED)
+    set_target_properties(GBM::GBM PROPERTIES
+                                   IMPORTED_LOCATION "${GBM_LIBRARY}"
+                                   INTERFACE_INCLUDE_DIRECTORIES "${GBM_INCLUDE_DIR}")
+  endif()
+endif()
+
+mark_as_advanced(GBM_INCLUDE_DIR GBM_LIBRARY)