On 03/26/2017 04:42 AM, Nguyễn Thái Ngọc Duy wrote:
> files-backend.c is unlearning submodules. Instead of having a specific
> check for submodules to see what operation is allowed, files backend
> now takes a set of flags at init. Each operation will check if the
> required flags is present before performing.
>
> For now we have four flags: read, write and odb access. Main ref store
> has all flags, obviously, while submodule stores are read-only and have
> access to odb (*).
>
> The "main" flag stays because many functions in the backend calls
> frontend ones without a ref store, so these functions always target the
> main ref store. Ideally the flag should be gone after ref-store-aware
> api is in place and used by backends.
>
> (*) Submodule code needs for_each_ref. Try take REF_STORE_ODB flag
> out. At least t3404 would fail. The "have access to odb" in submodule is
> a bit hacky since we don't know from he whether add_submodule_odb() has
> been called.
>
> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx>
> ---
> refs.c | 15 +++++++---
> refs/files-backend.c | 81 +++++++++++++++++++++++++++++++++-------------------
> refs/refs-internal.h | 9 +++++-
> 3 files changed, 71 insertions(+), 34 deletions(-)
>
> diff --git a/refs.c b/refs.c
> index d72b48a430..241b4227b2 100644
> --- a/refs.c
> +++ b/refs.c
> [...]
> @@ -1481,7 +1486,9 @@ struct ref_store *get_ref_store(const char *submodule)
> return NULL;
> }
>
> - refs = ref_store_init(submodule_sb.buf);
> + /* pretend that add_submodule_odb() has been called */
The word "pretend" implies that the thing that follows is not true,
whereas we hope that it *is* true. It would be better to say "assume".
> + refs = ref_store_init(submodule_sb.buf,
> + REF_STORE_READ | REF_STORE_ODB);
> register_submodule_ref_store(refs, submodule);
>
> strbuf_release(&submodule_sb);
> diff --git a/refs/files-backend.c b/refs/files-backend.c
> index 490f05a6f4..d97a924860 100644
> --- a/refs/files-backend.c
> +++ b/refs/files-backend.c
> [...]
> @@ -994,13 +997,17 @@ static struct ref_store *files_ref_store_create(const char *gitdir)
> }
>
> /*
> - * Die if refs is for a submodule (i.e., not for the main repository).
> - * caller is used in any necessary error messages.
> + * Die if refs is not the main ref store. caller is used in any
> + * necessary error messages.
> */
> static void files_assert_main_repository(struct files_ref_store *refs,
> const char *caller)
> {
> - /* This function is to be fixed up in the next patch */
> + if (refs->store_flags & REF_STORE_MAIN)
> + return;
> +
> + die("BUG: unallowed operation (%s), only works "
> + "on main ref store\n", caller);
"Unallowed" isn't really a word; one would say "disallowed". But it
might sound better to say
BUG: operation %s only allowed for main ref store
> }
>
> /*
> @@ -1009,9 +1016,9 @@ static void files_assert_main_repository(struct files_ref_store *refs,
> * files_ref_store is for a submodule (i.e., not for the main
> * repository). caller is used in any necessary error messages.
> */
> -static struct files_ref_store *files_downcast(
> - struct ref_store *ref_store, int submodule_allowed,
> - const char *caller)
> +static struct files_ref_store *files_downcast(struct ref_store *ref_store,
> + unsigned int required_flags,
> + const char *caller)
The docstring for this function needs to be updated; it still talks
about the old `submodule_allowed` parameter.
> {
> struct files_ref_store *refs;
>
> @@ -1021,8 +1028,9 @@ static struct files_ref_store *files_downcast(
>
> refs = (struct files_ref_store *)ref_store;
>
> - if (!submodule_allowed)
> - files_assert_main_repository(refs, caller);
> + if ((refs->store_flags & required_flags) != required_flags)
> + die("BUG: unallowed operation (%s), requires %x, has %x\n",
> + caller, required_flags, refs->store_flags);
Same comment about "unallowed". Maybe
BUG: operation %s requires abilities 0x%x but only have 0x%x
>
> return refs;
> }
> [...]
Michael