On Mon, Nov 08 2021, Taylor Blau wrote: > On Sat, Nov 06, 2021 at 10:10:50PM +0100, Ævar Arnfjörð Bjarmason wrote: >> The "struct grep_opt" is a mixture of things that would be needed by >> all callers of the grep.c API, and quite a few things that only the >> builtin/grep.c needs. >> >> Since we got rid of "prefix_length" in the previous commit, let's move >> the "prefix" variable over to "builtin/grep.c" where it's used. To do >> this let's create a "struct grep_cmd_opt", which we'll have a pointer >> to in a new "caller_priv" member in "struct grep_opt" (the existing >> "priv" is used by the top-level "grep.c" itself). > > I'm definitely in favor of removing specialized, caller-specific bits > from an internal API. But I'm not sure why grep.c needs to keep track o > this new "caller_priv" field at all. > > Among the uses of `prefix` in builtin/grep.c, I see grep_source_name, > and the call to run_pager(). Would it be more straightforward to pass > down prefix from cmd_grep down to its use in grep_source_name? > > There are quite a few intermediary functions that we go through to get > from cmd_grep() down to grep_source_name(). For instance, we could reach > it through: > > cmd_grep -> grep_tree -> grep_submodule -> grep_cache -> grep_oid -> > grep_source_name > > But passing prefix from cmd_grep down to grep_source_name without > relying on the internals of grep.c seems like a good direction to me. I > could even buy that (ab)using a static variable in builtin/grep.c to > keep track of a constant prefix value would save you some plumbing > (though I'd rather see the usage spelled out more explicitly). > > All of that is to say that I share your motivation for this patch and > think that the direction is good, but I would have preferred to do it > without the caller_priv variable (unless there is something that I am > missing here). Yes, that would make much more sense. I just had tunnel vision while writing this, evidently. Yeah, just either passing it or using a static variable in grep.c would make more sense. Arguably we could even have it be read only (const char *const) and have a global "the_prefix" or something, but it's probably not widely used enough for that to make sense.
