Re: [PATCH 1/3] submodule.c: add has_submodules to check if we have any submodules

From: Stefan Beller <sbeller@google.com>
Date: May 18, 2017, 19:15 UTC
Message-ID: <CAGZ79kb+31h6f_9fuUpbfeY7xxjP-kbvqz6J5K5sbPEmdPNvpw@mail.gmail.com>
In-Reply-To: <20170518190027.GD112091@google.com>

On Thu, May 18, 2017 at 12:00 PM, Brandon Williams <bmwill@google.com> wrote:

Show 25 quoted lines

> On 05/18, Stefan Beller wrote:
>> >> +static enum {
>> >> +     SUBMODULE_CONFIG_NOT_READ = 0,
>> >> +     SUBMODULE_CONFIG_NO_CONFIG,
>> >> +     SUBMODULE_CONFIG_EXISTS,
>> >> +} submodule_config_reading;
>> >
>> > Any way we can have this not be a global, but rather a parameter?  You
>> > could pass in a pointer to this value via the callback data parameter in
>> > the submodule_config function.
>>
>> As said in the reply to Junio, this patch has been sitting on my hard drive
>> for a while and was written before you started the attempt to de-globalize
>> the state of git.
>>
>> Ideally this setting would be part of the repository object. For example
>> the repository object would have a "submodule_config" pointer, initialized
>> to NULL, which can then be set to the read config or a static empty_config
>> if no such config exists.
>
> I'm not quite sure I agree, or rather we may be talking about two
> different things or I'm misinterpreting the patches.  From these patches
> it seems like 'submodule_config' that you are refering to is not the
> actual submodule configuration but rather some options that are stored
> in .git/config or other various config locations (home, system, etc).

You are reading the patch correctly.

> What would need to be part of the repository object (and is in my WIP
> that I'll hopefully send out so i can get some feedback) would be the
> submodule_cache which is the internal representation of a repository's
> .gitmodules files.

and in the light of this patch, we'd want to have a cache the flag if the regular config contains any submodule related things, so for now a static seems to be the best option and once we have the repo object we'd have a bit from the flags section (assuming we'll have a flags section down the road):

struct repo {
    ....
    struct regular_config *config_ptr;
    unsigned config_has_submodule_stuff : 1;
    unsigned config_loaded_submodule_config : 1;
}

Then the caching decision would be:

static int submodule_config(const char *var, const char *value, void *cb)
{
       struct repo *r = cb;
       if (!strcmp(var, "submodule.fetchjobs")) {
               r->config_has_submodule_stuff = 1;
               parallel_jobs = git_config_int(var, value);
               if (parallel_jobs < 0)
                       die(_("negative values not allowed for
submodule.fetchJobs"));
               return 0;
       } else if (starts_with(var, "submodule.")) {
               r->config_has_submodule_stuff = 1;
               return parse_submodule_config_option(var, value);
       } else if (!strcmp(var, "fetch.recursesubmodules")) {
               r->config_has_submodule_stuff = 1;
               config_fetch_recurse_submodules =
parse_fetch_recurse_submodules_arg(var, value);
               return 0;
       }
       return 0;
}

void load_submodule_config(struct repo *r)
{
      # assume r->config_has_submodule_stuff and config_loaded_submodule_config
      # was set to 0 on repo init
      if (r->config_loaded_submodule_config)
            return;

      git_config(submodule_config, r);
      r->config_loaded_submodule_config = 1;
}

That said, I agree that the

Show 5 quoted lines

>> >> +static enum {
>> >> +     SUBMODULE_CONFIG_NOT_READ = 0,
>> >> +     SUBMODULE_CONFIG_NO_CONFIG,
>> >> +     SUBMODULE_CONFIG_EXISTS,
>> >> +} submodule_config_reading;

with its global state is counterproductive for your series, but I see an easy integration path. As we do not have the repo struct, I proposed it this way to make submodule progress.

Thanks, Stefan