Re: fdopendir: Fix fd leak and test failure on native Windows

[KO Myung-Hun]

Bruno Haible wrote:
> KO Myung-Hun wrote:
>>> @@ -78,11 +82,17 @@ _gl_unregister_dirp_fd (int fd)
>>>  int
>>>  dirfd (DIR *dir_p)
>>>  {
>>> +#if GNULIB_defined_DIR
>>> +  int fd = dir_p->fd_to_close;
>>
>> dirfd() allows to take an invalid `dir_p' ?
> 
> No; this must be a misunderstanding.
> 
> dirfd is specified at
> https://pubs.opengroup.org/onlinepubs/9699919799/functions/dirfd.html
> Which says that if "The dirp argument does not refer to a valid directory 
> stream"
> the function may fail with error EINVAL. It may alternatively simply crash
> ("the behavior is undefined").
> 

Then, gnulib decided to crash instead of returning -1 with setting errno
to EINAL if dir_p has the garbage value which is not returned by opendir() ?

> In this code, we have two cases, depending on platforms:
>   - If GNULIB_defined_DIR, it means that gnulib has defined or overridden
>     the 'DIR' type, to include an 'fd_to_close' field'.
>     Currently that's only on native Windows, but I'm suggesting that the same
>     code could also be used on kLIBC.
>   - Otherwise, gnulib uses either the system-provided dirfd function or macro,
>     or does a lookup in dir_p->d_fd or dir_p->dd_fd.
> 
> Bruno
> 
> 
> 

-- 
KO Myung-Hun

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