Re: [PATCH] get_sha1: support relative path "<obj>:<sth>" syntax

[Nguyen Thai Ngoc Duy <pclouds@gmail.com>]

2010/11/11 Junio C Hamano <gitster@pobox.com>:
> Nguyễn Thái Ngọc Duy  <pclouds@gmail.com> writes:
>
>>               if (namelen < 3 ||
>>                   name[2] != ':' ||
>> -                 name[1] < '0' || '3' < name[1])
>> +                 name[1] < '0' || '3' < name[1]) {
>>                       cp = name + 1;
>> +                     if (startup_info && cp[0] == '.' &&
>> +                         (cp[1] == '/' || (cp[1] == '.' && cp[2] == '/'))) {
>> +                             new_path = prefix_path(startup_info->prefix,
>> +                                                    strlen(startup_info->prefix),
>> +                                                    cp);
>> +                             cp = new_path;
>> +                     }
>> +             }
>
> What does this new codepath do when we know where the working tree is and
> we are outside of the working tree (e.g. we are looking at the index or a
> commit in a submodule from above the superproject)?
>
> What should it do?

Prefix is NULL in that case. So no prefixing, git will complain the
given path does not exist (although it should say "./" syntax is not
usable without a worktree).

prefix_path() dies if the resolved path is outside repo. So no, users
can't look up files in superproject from a subproject. I think we need
to define the superproject/subproject relation first. I have
$HOME/.git, but I don't think it's a superproject to any repos inside
my $HOME.
-- 
Duy