From: Karthik Nayak <karthik.188@gmail.com>
Date: Wed, 19 Nov 2025 16:27:29 GMT
Subject: Re: [PATCH 14/18] streaming: make the `odb_read_stream` definition public
Message-ID: <CAOLa=ZT_VFfbfLVdvHUqK5C6k4zROLQs0Pt5rOWL_hE_BSfGeg@mail.gmail.com>
In-Reply-To: <20251119-b4-pks-odb-read-stream-v1-14-adacf03c2ccf@pks.im>

Patrick Steinhardt <ps@pks.im> writes:

> 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.
>

This was a question I had in mind in one of the previous patches, looks
like we're going in that direction. Makes sense to me.

> Make the stream definition public to prepare for this.
>
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---
>  streaming.c | 11 -----------
>  streaming.h | 15 ++++++++++++++-
>  2 files changed, 14 insertions(+), 12 deletions(-)
>
> diff --git a/streaming.c b/streaming.c
> index 9e20e9a882..3f94bd2a03 100644
> --- a/streaming.c
> +++ b/streaming.c
> @@ -12,19 +12,8 @@
>  #include "replace-object.h"
>  #include "packfile.h"
>
> -typedef int (*close_istream_fn)(struct odb_read_stream *);
> -typedef ssize_t (*read_istream_fn)(struct odb_read_stream *, char *, size_t);
> -
>  #define FILTER_BUFFER (1024*16)
>
> -struct odb_read_stream {
> -	close_istream_fn close;
> -	read_istream_fn read;
> -
> -	enum object_type type;
> -	unsigned long size; /* inflated size of full object */
> -};
> -
>  /*****************************************************************
>   *
>   * Filtered stream
> diff --git a/streaming.h b/streaming.h
> index 95c2a434fa..3a850e3efc 100644
> --- a/streaming.h
> +++ b/streaming.h
> @@ -6,11 +6,24 @@
>
>  #include "object.h"
>
> -/* opaque */
>  struct object_database;
>  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 *);
>

If we're returning an `struct odb_read_stream` anyways, why take in
pointers for object size and object type? They'll be the same as
`odb_read_stream.type` and `odb_read_stream.size` no?