krb5 commit: Add zapfreedata() convenience function

https://github.com/krb5/krb5/commit/abd974cf867db5a398aa87ba9b9aaa34346e12a4
commit abd974cf867db5a398aa87ba9b9aaa34346e12a4
Author: Greg Hudson <[email protected]>
Date:   Thu Mar 14 11:26:44 2019 -0400

    Add zapfreedata() convenience function

 src/include/k5-int.h |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/src/include/k5-int.h b/src/include/k5-int.h
index 71dce73..f24e92c 100644
--- a/src/include/k5-int.h
+++ b/src/include/k5-int.h
@@ -666,6 +666,16 @@ zapfreestr(void *str)
     }
 }
 
+/* Convenience function: zap and free krb5_data pointer if it is non-NULL. */
+static inline void
+zapfreedata(krb5_data *data)
+{
+    if (data != NULL) {
+        zapfree(data->data, data->length);
+        free(data);
+    }
+}
+
 /*
  * Combine two keys (normally used by the hardware preauth mechanism)
  */