streaming: make the `odb_read_stream` definition public

Subsequent commits will move the backend-specific logic of setting up an
object read stream into the specific subsystems. As the backends are now
the ones that are responsible for allocating the stream they'll need to
have the stream definition available to them.

Make the stream definition public to prepare for this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/streaming.h b/streaming.h
index 148f6b3069..acfdef1598 100644
--- a/streaming.h
+++ b/streaming.h
@@ -7,10 +7,23 @@
 #include "object.h"
 
 struct object_database;
-/* opaque */
 struct odb_read_stream;
 struct stream_filter;
 
+typedef int (*odb_read_stream_close_fn)(struct odb_read_stream *);
+typedef ssize_t (*odb_read_stream_read_fn)(struct odb_read_stream *, char *, size_t);
+
+/*
+ * A stream that can be used to read an object from the object database without
+ * loading all of it into memory.
+ */
+struct odb_read_stream {
+	odb_read_stream_close_fn close;
+	odb_read_stream_read_fn read;
+	enum object_type type;
+	unsigned long size; /* inflated size of full object */
+};
+
 struct odb_read_stream *open_istream(struct repository *, const struct object_id *,
 				     enum object_type *, unsigned long *,
 				     struct stream_filter *);