lzo: fix memcpy_backptr() with 0 offset

[ffmpeg] / libavutil / opt.h

diff --git a/libavutil/opt.h b/libavutil/opt.h
index 5fce09a5c8be46cb2e6503b893e99713c66c187f..0196056d6d94905cfeb93c6200ddf83b9b7e1f49 100644 (file)
--- a/libavutil/opt.h
+++ b/libavutil/opt.h
@@ -586,6 +586,17 @@ int av_opt_get_double(void *obj, const char *name, int search_flags, double
 int av_opt_get_q     (void *obj, const char *name, int search_flags, AVRational *out_val);
 /**
  * @}
+ */
+/**
+ * Gets a pointer to the requested field in a struct.
+ * This function allows accessing a struct even when its fields are moved or
+ * renamed since the application making the access has been compiled,
+ *
+ * @returns a pointer to the field, it can be cast to the correct type and read
+ *          or written to.
+ */
+void *av_opt_ptr(const AVClass *avclass, void *obj, const char *name);
+/**
  * @}
  */