Add function to SerdSink for freeing opaque handle

This can be used to associate dynamically allocated data with a sink and have
it managed along with the sink's lifetime.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/sink.h b/src/sink.h
index 57c52021..d9b5c59c 100644
--- a/src/sink.h
+++ b/src/sink.h
@@ -24,6 +24,7 @@
 */
 struct SerdSinkImpl {
 	void*             handle;
+	SerdFreeFunc      free_handle;
 	SerdBaseFunc      base;
 	SerdPrefixFunc    prefix;
 	SerdStatementFunc statement;