From: Eric Sunshine <sunshine@sunshineco.com>
Date: Wed, 24 Aug 2016 07:30:51 GMT
Subject: Re: [PATCH 10/15] sequencer: lib'ify save_head()
Message-ID: <CAPig+cSxeOkT7fLuCQrGJNabPfx1855+1-5pqcq0==22mzJk9w@mail.gmail.com>
In-Reply-To: <416659fa3df92eabf3265ec079a6ea8cbc17366f.1471968378.git.johannes.schindelin@gmx.de>

On Tue, Aug 23, 2016 at 12:07 PM, Johannes Schindelin
<johannes.schindelin@gmx.de> wrote:
> To be truly useful, the sequencer should never die() but always return
> an error.
>
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
> diff --git a/sequencer.c b/sequencer.c
> @@ -844,18 +844,22 @@ static int create_seq_dir(void)
> -static void save_head(const char *head)
> +static int save_head(const char *head)
>  {
>         static struct lock_file head_lock;
>         struct strbuf buf = STRBUF_INIT;
>         int fd;
>
> -       fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), LOCK_DIE_ON_ERROR);
> +       fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), 0);
> +       if (fd < 0)
> +               return error_errno(_("Could not lock HEAD"));
>         strbuf_addf(&buf, "%s\n", head);
>         if (write_in_full(fd, buf.buf, buf.len) < 0)
> -               die_errno(_("Could not write to %s"), git_path_head_file());
> +               return error_errno(_("Could not write to %s"),
> +                                  git_path_head_file());

Does this need to rollback the lockfile before returning?

>         if (commit_lock_file(&head_lock) < 0)
> -               die(_("Error wrapping up %s."), git_path_head_file());
> +               return error(_("Error wrapping up %s."), git_path_head_file());
> +       return 0;
>  }