add SkSafeRef / SkSafeUnref as inline static functions, to use in place of our

existing obj->safeRef(), which is unsafe since it can its 'if (this)' can be
optimized away by some compilers.

fix some overflows in mimpmap generation



git-svn-id: http://skia.googlecode.com/svn/trunk@181 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 17 insertions, 0 deletions

diff --git a/include/core/SkRefCnt.h b/include/core/SkRefCnt.h
index adb59ddc18..7e325e0002 100644
--- a/include/core/SkRefCnt.h
+++ b/include/core/SkRefCnt.h
@@ -130,5 +130,22 @@ private:
         dst = src;                      \
     } while (0)
 
+
+/** Check if the argument is non-null, and if so, call obj->ref()
+ */
+template <typename T> static inline void SkSafeRef(T* obj) {
+    if (obj) {
+        obj->ref();
+    }
+}
+
+/** Check if the argument is non-null, and if so, call obj->unref()
+ */
+template <typename T> static inline void SkSafeUnref(T* obj) {
+    if (obj) {
+        obj->unref();
+    }
+}
+
 #endif