On Sun, Mar 19, 2017 at 12:54 AM, Junio C Hamano <[email protected]> wrote: > Nguyễn Thái Ngọc Duy <[email protected]> writes: > >> setup_git_env() must be called before this function to initialize >> git_common_dir so that it returns a non NULL string. And it must return >> a non NULL string or segfault can happen because all callers expect so. >> >> Normally if somebody has called get_git_dir(), or set_git_dir() then >> setup_git_env() is already called. But if you do setup_git_directory() >> at top dir (which skips set_git_dir) and never call get_git_dir, you'll >> get NULL here. > > Hmph, and the solution for the problem not being "so let's make sure > get_git_dir() is called even when the command is started at the top > directory" is because...?
-EHARDTOPARSE. There's a hidden dependency between get_git_dir() and get_git_common_dir() which is not good. If we lazily call set_git_env(), make sure we do it lazily but consistently at all relevant function calls (i.e. including get_git_common_dir). Alternatively (I was thinking of this but didn't really follow up because this was side issue) we should make sure setup_git_env() is always called at the end of setup_git_dir...() and remove the laziness in get_git_dir(). This may be more in line of recent attempts to catch repo access without calling setup_git_directory..() first. But sadly I haven't read Jeff's series, so I can't say whether it's true. -- Duy
