Re: git: 643336549081 - main - If copy_file_range(2) fails with EXDEV, use fall-back.

On Tue, Apr 04, 2023 at 07:40:44AM +0000, Poul-Henning Kamp wrote:
> commit 64333654908153cd8e2dcb408c57cc3e3c4f29af
> 
>   If copy_file_range(2) fails with EXDEV, use fall-back.
> ---
>  bin/cp/utils.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/bin/cp/utils.c b/bin/cp/utils.c
> index 8c1c350ff6f1..9794152ac724 100644
> --- a/bin/cp/utils.c
> +++ b/bin/cp/utils.c
> @@ -180,7 +180,7 @@ copy_file(const FTSENT *entp, int dne)
>  	if (use_copy_file_range) {
>  		wcount = copy_file_range(from_fd, NULL,
>  		    to_fd, NULL, SSIZE_MAX, 0);

Interesting.  After commit c98a764c681f, which changed bufsize to
SSIZE_MAX above, my ports tinderbox started to fail when copying
packages and they come out zero-sized at destination.  I've tried
to write a simple example to reproduce it and file a PR, but the
bug was evasive, so I just reverted that commit locally.

May I ask how did you arrive at this fix below?  Did you observe
something similar, or my issue has nothing to do with it?

> -		if (wcount < 0 && errno == EINVAL) {
> +		if (wcount < 0 && (errno == EINVAL || errno == EXDEV)) {
>  			/* Prob a non-seekable FD */
>  			use_copy_file_range = 0;
>  		}

./danfe