3 files changed, 8 insertions, 10 deletions
diff --git a/include/mbgl/platform/default/headless_view.hpp b/include/mbgl/platform/default/headless_view.hpp
index c0baddb884..f140338349 100644
--- a/include/mbgl/platform/default/headless_view.hpp
+++ b/include/mbgl/platform/default/headless_view.hpp
@@ -27,7 +27,7 @@ public:
     void createContext();
 
     void resize(uint16_t width, uint16_t height, float pixelRatio);
-    const std::unique_ptr<uint32_t[]> readPixels();
+    std::unique_ptr<uint32_t[]> readPixels();
 
     void notify();
     void notify_map_change(MapChange change, timestamp delay = 0);
diff --git a/include/mbgl/util/image.hpp b/include/mbgl/util/image.hpp
index dc8f6a8150..b2f70e1442 100644
--- a/include/mbgl/util/image.hpp
+++ b/include/mbgl/util/image.hpp
@@ -2,31 +2,29 @@
 #define MBGL_UTIL_IMAGE
 
 #include <string>
-#include <cstring>
-#include <stdexcept>
+#include <memory>
 
 namespace mbgl {
 namespace util {
 
-std::string compress_png(int width, int height, void *rgba, bool flip = false);
+std::string compress_png(int width, int height, void *rgba);
 
 
 class Image {
 public:
-    Image(const std::string &img, bool flip = false);
-    ~Image();
+    Image(const std::string &img);
 
-    inline const char *getData() const { return img; }
+    inline const char *getData() const { return img.get(); }
     inline uint32_t getWidth() const { return width; }
     inline uint32_t getHeight() const { return height; }
+    inline operator bool() const { return img && width && height; }
 
 private:
     // loaded image dimensions
     uint32_t width = 0, height = 0;
 
     // the raw image data
-    char *img = nullptr;
-
+    std::unique_ptr<char[]> img;
 };
 
 
diff --git a/include/mbgl/util/token.hpp b/include/mbgl/util/token.hpp
index 0f045f434a..64192a99f9 100644
--- a/include/mbgl/util/token.hpp
+++ b/include/mbgl/util/token.hpp
@@ -22,7 +22,7 @@ std::string replaceTokens(const std::string &source, const Lookup &lookup) {
         result.append(pos, brace);
         pos = brace;
         if (pos != end) {
-            for (brace++; brace != end && std::isalnum(*brace); brace++);
+            for (brace++; brace != end && (std::isalnum(*brace) || *brace == '_'); brace++);
             if (brace != end && *brace == '}') {
                 result.append(lookup({ pos + 1, brace }));
                 pos = brace + 1;