"Derrick Stolee via GitGitGadget" <gitgitgadget@xxxxxxxxx> writes:
> +int branch_checked_out(const char *refname, char **path)
> +{
> + struct worktree **worktrees = get_worktrees();
> + const struct worktree *wt = find_shared_symref(worktrees, "HEAD", refname);
> + int result = wt && !wt->is_bare;
> +
> + if (result && path)
> + *path = xstrdup(wt->path);
> +
> + free_worktrees(worktrees);
> + return result;
> +}
Don't you plan to call this repeatedly from the for_each_deco
iteration? I am wondering if it should take the result of
get_worktrees() and reuse the result of get_worktrees(), instead of
enumerating the list of worktrees and freeing for each of the
branches you need to inspect.
There also was another topic
https://lore.kernel.org/git/pull.1266.v2.git.git.1652690501963.gitgitgadget@xxxxxxxxx/
that was triggered by find_shared_symref() being relatively
heavy-weight, which suggests a more involved refactoring.
I wonder if we rather want to rewrite find_shared_symref() *not* to
take the target parameter at all, and instead introduce a new
function that takes a worktree, and report the branch that is
checked out (or being operated on via rebase or bisect). Then we
can
- create a strset out of its result, i.e. set of branches that
should not be touched;
- iterate over refs that point into the history being rebased
(using for_each_decoration()), and consult that strset to see if
any of them is being rewritten.
With the API of find_shared_symref(), we'd need to iterate over all
worktrees for each decoration. With such a restructuring, we can
iterate over all worktrees just once, and match the result with
decoration, so the problem becomes O(N)+O(M) and not O(N*M) for
number of worktrees N and number of decorations M.
