Re: Patch: incorrect array offset in backend replication tar header - Mailing list pgsql-hackers

Actually I found one other issue while continuing my investigation.
The insertion of the 'ustar' and version '00' has the '00' version at
the wrong offset. The patch is attached.

-- Brian

On Mon, Sep 24, 2012 at 7:51 PM, Brian Weaver <cmdrclueless@gmail.com> wrote:
> While researching the way streaming replication works I was examining
> the construction of the tar file header. By comparing documentation on
> the tar header format from various sources I certain the following
> patch should be applied to so the group identifier is put into thee
> header properly.
>
> While I realize that wikipedia isn't always the best source of
> information, the header offsets seem to match the other documentation
> I've found. The format is just easier to read on wikipedia
>
> http://en.wikipedia.org/wiki/Tar_(file_format)#File_header
>
> Here is the trivial patch:
>
> diff --git a/src/backend/replication/basebackup.c
> b/src/backend/replication/basebackup.c
> index 4aaa9e3..524223e 100644
> --- a/src/backend/replication/basebackup.c
> +++ b/src/backend/replication/basebackup.c
> @@ -871,7 +871,7 @@ _tarWriteHeader(const char *filename, const char
> *linktarget,
>         sprintf(&h[108], "%07o ", statbuf->st_uid);
>
>         /* Group 8 */
> -       sprintf(&h[117], "%07o ", statbuf->st_gid);
> +       sprintf(&h[116], "%07o ", statbuf->st_gid);
>
>         /* File size 12 - 11 digits, 1 space, no NUL */
>         if (linktarget != NULL || S_ISDIR(statbuf->st_mode))
>
>
> -- Brian
>
> --
>
> /* insert witty comment here */



--

/* insert witty comment here */