avutil/common: Add FF_PTR_ADD()

Suggested-by: Andreas Rheinhardt
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavutil/internal.h b/libavutil/internal.h
index 572daefec3ead7ee5eab0496886988457a402612..2ed1c2abb167fa8ad6d3f2157b41eefaf611d614 100644 (file)
--- a/libavutil/internal.h
+++ b/libavutil/internal.h
@@ -102,6 +102,8 @@
 #define FF_ALLOC_TYPED_ARRAY(p, nelem)  (p = av_malloc_array(nelem, sizeof(*p)))
 #define FF_ALLOCZ_TYPED_ARRAY(p, nelem) (p = av_mallocz_array(nelem, sizeof(*p)))
 
+#define FF_PTR_ADD(ptr, off) ((off) ? (ptr) + (off) : (ptr))
+
 #include "libm.h"
 
 /**