+/* Thread-safe, lock-free, FT_Library */
+
+static FT_Library ft_library;
+
+static
+void free_ft_library (void)
+{
+ FT_Done_FreeType (ft_library);
+}
+
+static FT_Library
+get_ft_library (void)
+{
+retry:
+ FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library);
+
+ if (unlikely (!library))
+ {
+ /* Not found; allocate one. */
+ if (FT_Init_FreeType (&library))
+ return NULL;
+
+ if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) {
+ FT_Done_FreeType (library);
+ goto retry;
+ }
+
+#ifdef HAVE_ATEXIT
+ atexit (free_ft_library); /* First person registers atexit() callback. */
+#endif
+ }
+
+ return library;
+}
+
+static void
+_release_blob (FT_Face ft_face)
+{
+ hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
+}
+
+void
+hb_ft_font_set_funcs (hb_font_t *font)
+{
+ hb_blob_t *blob = hb_face_reference_blob (font->face);
+ unsigned int blob_length;
+ const char *blob_data = hb_blob_get_data (blob, &blob_length);
+ if (unlikely (!blob_length))
+ DEBUG_MSG (FT, font, "Font face has empty blob");
+
+ FT_Face ft_face = NULL;
+ FT_Error err = FT_New_Memory_Face (get_ft_library (),
+ (const FT_Byte *) blob_data,
+ blob_length,
+ hb_face_get_index (font->face),
+ &ft_face);
+
+ if (unlikely (err)) {
+ hb_blob_destroy (blob);
+ DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
+ return;
+ }
+
+ FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE);
+
+ FT_Set_Char_Size (ft_face,
+ font->x_scale, font->y_scale,
+ font->x_ppem * 72 * 64 / font->x_scale,
+ font->y_ppem * 72 * 64 / font->y_scale);
+
+ ft_face->generic.data = blob;
+ ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
+
+ hb_font_set_funcs (font,
+ _hb_ft_get_font_funcs (),
+ ft_face,
+ (hb_destroy_func_t) FT_Done_Face);
+}
+
+FT_Face
+hb_ft_font_get_face (hb_font_t *font)
+{
+ if (font->destroy == (hb_destroy_func_t) FT_Done_Face ||
+ font->destroy == (hb_destroy_func_t) _do_nothing)
+ return (FT_Face) font->user_data;
+
+ return NULL;
+}