fix(freetype): fix return value and add more check (#5218)

src/libs/freetype/lv_freetype.c

@@ -371,7 +371,7 @@ static bool cache_node_cache_create_cb(lv_freetype_cache_node_t * node, void * u
     FT_Error error = FT_New_Face(ctx->library, node->pathname, 0, &face);
     if(error) {
         FT_ERROR_MSG("FT_New_Face", error);
-        return NULL;
+        return false;
     }
 
     node->ref_size = LV_FREETYPE_OUTLINE_REF_SIZE_DEF;
@@ -381,7 +381,7 @@ static bool cache_node_cache_create_cb(lv_freetype_cache_node_t * node, void * u
     if(error) {
         FT_Done_Face(face);
         FT_ERROR_MSG("FT_Set_Char_Size", error);
-        return NULL;
+        return false;
     }
 
     if(node->style & LV_FREETYPE_FONT_STYLE_ITALIC) {

src/libs/freetype/lv_freetype_outline.c

@@ -75,6 +75,11 @@ bool lv_freetype_outline_font_create(lv_freetype_font_dsc_t * dsc)
     dsc->cache_node->draw_data_cache = lv_cache_create(&lv_cache_class_lru_rb_count, sizeof(lv_freetype_outline_node_t),
                                                        LV_FREETYPE_CACHE_FT_GLYPH_CNT,
                                                        glyph_outline_cache_ops);
+    if(dsc->cache_node->draw_data_cache == NULL
+       || dsc->cache_node->glyph_cache == NULL) {
+        LV_LOG_ERROR("draw data cache creating failed");
+        return false;
+    }
 
     LV_LOG_INFO("outline cache(name: %s, style: 0x%x) create %p, ref_cnt = %d",
                 dsc->cache_node->pathname,