Implement SDL_Surface refcounting

3 files changed, 24 insertions, 0 deletions

diff --git a/src/library_sdl.js b/src/library_sdl.js
index b7d73862..34c9551a 100644
--- a/src/library_sdl.js
+++ b/src/library_sdl.js
@@ -361,6 +361,13 @@ var LibrarySDL = {
     },
 
     freeSurface: function(surf) {
+      var refcountPointer = surf + Runtime.QUANTUM_SIZE * 14;
+      var refcount = {{{ makeGetValue('refcountPointer', '0', 'i32') }}};
+      if (refcount > 0) {
+        {{{ makeSetValue('refcountPointer', '0', 'refcount - 1', 'i32') }}};
+        return;
+      }
+
       var info = SDL.surfaces[surf];
       if (!info.usePageCanvas && info.canvas) SDL.canvasPool.push(info.canvas);
       _free(info.buffer);
diff --git a/tests/runner.py b/tests/runner.py
index 0efcce86..6daa9c36 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -13172,6 +13172,9 @@ Press any key to continue.'''
     def test_sdl_alloctext(self):
       self.btest('sdl_alloctext.c', expected='1', args=['-O2', '-s', 'TOTAL_MEMORY=' + str(1024*1024*8)])
 
+    def test_sdl_surface_refcount(self):
+      self.btest('sdl_surface_refcount.c', expected='1')
+
     def test_glbegin_points(self):
       shutil.copyfile(path_from_root('tests', 'screenshot.png'), os.path.join(self.get_dir(), 'screenshot.png'))
       self.btest('glbegin_points.c', reference='glbegin_points.png', args=['--preload-file', 'screenshot.png'])
diff --git a/tests/sdl_surface_refcount.c b/tests/sdl_surface_refcount.c
new file mode 100644
index 00000000..4e9b4896
--- /dev/null
+++ b/tests/sdl_surface_refcount.c
@@ -0,0 +1,14 @@
+#include <SDL.h>
+
+int main(int argc, char *argv[])
+{
+    SDL_Init(SDL_INIT_VIDEO);
+    SDL_Surface *screen = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE);
+    SDL_Surface *reference = screen;
+    reference->refcount++;
+    SDL_FreeSurface(screen);
+    SDL_FreeSurface(reference);
+    int result = 1;
+    REPORT_RESULT();
+    return 0;
+}