Re: [PATCH] sha1_file.c:create_tmpfile(): Fix race when creating loose object dirs

From: Duy Nguyen <pclouds@gmail.com>
Date: Oct 18, 2013, 13:55 UTC
Message-ID: <CACsJy8C=kaa2OgdxOrefP+Ck_sSA00tHs9UqMXwkh9v4K3Mdvg@mail.gmail.com>
In-Reply-To: <1382102267-18151-1-git-send-email-johan@herland.net>

On Fri, Oct 18, 2013 at 8:17 PM, Johan Herland <johan@herland.net> wrote:

Show 13 quoted lines

> diff --git a/sha1_file.c b/sha1_file.c
> index f80bbe4..00ffffe 100644
> --- a/sha1_file.c
> +++ b/sha1_file.c
> @@ -2857,7 +2857,9 @@ static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
>                 /* Make sure the directory exists */
>                 memcpy(buffer, filename, dirlen);
>                 buffer[dirlen-1] = 0;
> -               if (mkdir(buffer, 0777) || adjust_shared_perm(buffer))
> +               if (mkdir(buffer, 0777) && errno != EEXIST)
> +                       return -1;
> +               if (adjust_shared_perm(buffer))
>                         return -1;

I was going to ask what if the created directory does not have permission 0777. But adjust_shared_perm follows immediately after, so we're good. It also answers the question why "mkdir(buffer, mode) && errno != EEXIST" should not be wrapped in xmkdir() or something to be used in other places as well. Thanks.

-- 
Duy