> > - if (argc != arg + 2 - commits_on_stdin)
> > + if (argc != arg + 2 - (commits_on_stdin || packfile))
> > usage(http_fetch_usage);
> > if (commits_on_stdin) {
> > commits = walker_targets_stdin(&commit_id, &write_ref);
> > + } else if (packfile) {
> > + /* URL will be set later */
>
> Prefer to see an empty statement spelled more explicitly, like this:
>
> ; /* URL will be set later */
>
> Otherwise reader would be left wondering if a line was (or lines
> were) accidentally lost after this comment.
OK.
> The above probably want to be a single helper function.
>
> The other side of if/else may also become another helper function.
>
> That way, the flow of control would become clearer. After all,
> these two branches do not share all that much. Only http-init and
> http-cleanup and nothing else.
>
> For that matter, even before introducing this new mode of operation,
> another patch to make a preparatory move of the original logic in
> this function to a helper function that would be called from the
> "else" side may make it easier to see what is going on.
OK.
> > diff --git a/http.c b/http.c
> > index 130e9d6259..ac66215ee6 100644
> > --- a/http.c
> > +++ b/http.c
> > @@ -2280,15 +2280,18 @@ int finish_http_pack_request(struct http_pack_request *preq)
> > int tmpfile_fd;
> > int ret = 0;
> >
> > - close_pack_index(p);
> > + if (p)
> > + close_pack_index(p);
> >
> > fclose(preq->packfile);
> > preq->packfile = NULL;
> >
> > - lst = preq->lst;
> > - while (*lst != p)
> > - lst = &((*lst)->next);
> > - *lst = (*lst)->next;
> > + if (p) {
> > + lst = preq->lst;
> > + while (*lst != p)
> > + lst = &((*lst)->next);
> > + *lst = (*lst)->next;
> > + }
>
> This is quite ugly. What is the original meaning of the target
> field of the pack_request structure again? A packed_git structure
> that will be filled when we are done fetching the packfile from the
> other side and installed in our repository? When we are (ab)using
> http_fetch code to fetch a single packfile, we do not install the
> packfile into the running process, because we are only (re)using the
> existing machinery as a poor-man's "curl | git index-pack --stdin"?
>
> I do not think it is a bad idea to roll "curl | git index-pack
> --stdin" our own, but I do find this an ugly way to do so. Perhaps
> a set of lower-level helper functions can be isolated out of the
> existing code before this new feature is added, and then a new "just
> fetch and pipe it to the index-pack" feature should be written using
> these helpers but with a separate set of entry points? Would it be
> a good way to make the resulting code cleaner than this patch does?
> I dunno.
OK - I'll extract the functions as you suggested earlier in the email,
and then it might be more obvious if it can be done more cleanly.
> > diff --git a/http.h b/http.h
> > index a5b082f3ae..709dfa4c19 100644
> > --- a/http.h
> > +++ b/http.h
> > @@ -223,12 +223,21 @@ struct http_pack_request {
> > struct active_request_slot *slot;
> >
> > /*
> > - * After calling new_http_pack_request(), point lst to the head of the
> > + * After calling new_http_pack_request(), if fetching a pack that
> > + * http_get_info_packs() told us about, point lst to the head of the
> > * pack list that target is in. finish_http_pack_request() will remove
> > * target from lst and call install_packed_git() on target.
> > */
> > struct packed_git **lst;
> >
> > + /*
> > + * If this is true, finish_http_pack_request() will pass "--keep" to
> > + * index-pack, resulting in the creation of a keep file, and will not
> > + * suppress its stdout (that is, the "keep\t<hash>\n" line will be
> > + * printed to stdout).
> > + */
> > + unsigned generate_keep : 1;
> > +
>
> I suspect that this is a sign that this single patch is trying to
> do too many things at the same time.
>
> - Whether we are fetching a single packfile from a URL, or walking
> to fetch all the packfiles in the repository at a given URL
>
> - Whether packfiles taken from outer space are marked with the
> "keep" bit
>
> - Whether the obtained packfile(s) are internally "installed"
> to the running process
>
> are conceptually independent choices, but somehow mixed up, it
> seems.
You might be right...I needed another mode that does the opposite
choices in these 3 points and these points because options that could be
toggled independently. I'll see if there is a better way to do this.
