Re: [PATCH 2/6] Open a directory with the usual flags

Corinna Vinschen <[email protected]> Wed, 10 Oct 2018 11:50:19 +0200

Newsgroups	gmane.comp.lib.newlib
Message-ID	<[email protected]>

On Oct  8 15:38, Sebastian Huber wrote:
> Use O_RDONLY since you are not supposed to write to a directory.
> 
> Use O_DIRECTORY as mandated by POSIX (The Open Group Base Specifications
> Issue 7, 2018 edition IEEE Std 1003.1-2017):
> 
> "If the type DIR is implemented using a file descriptor, the descriptor
> shall be obtained as if the O_DIRECTORY flag was passed to open()."
> 
> Use O_CLOEXEC as mandated by POSIX:
> 
> "When a file descriptor is used to implement the directory stream, it
> behaves as if the FD_CLOEXEC had been set for the file descriptor."
> 
> Drop the fcntl() call in favour of O_CLOEXEC.

Yeah, that really makes sense, but what about targets not (yet)
implementing O_CLOEXEC???  I'm not sure how to handle this, if
we have to handle that at all.


Thoughts?
Corinna


> Signed-off-by: Sebastian Huber <[email protected]>
> ---
>  newlib/libc/posix/opendir.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/newlib/libc/posix/opendir.c b/newlib/libc/posix/opendir.c
> index 1416f1053..650cbfe8d 100644
> --- a/newlib/libc/posix/opendir.c
> +++ b/newlib/libc/posix/opendir.c
> @@ -49,17 +49,12 @@ static char sccsid[] = "@(#)opendir.c	5.11 (Berkeley) 2/23/91";
>  DIR *
>  opendir (const char *name)
>  {
> -	register DIR *dirp;
> -	register int fd;
> -	int rc = 0;
> +	DIR *dirp;
> +	int fd;
>  
> -	if ((fd = open(name, 0)) == -1)
> +	if ((fd = open(name, O_RDONLY | O_DIRECTORY | O_CLOEXEC)) == -1)
>  		return NULL;
> -#ifdef HAVE_FCNTL
> -	rc = fcntl(fd, F_SETFD, 1);
> -#endif
> -	if (rc == -1 ||
> -	    (dirp = (DIR *)malloc(sizeof(DIR))) == NULL) {
> +	if ((dirp = (DIR *)malloc(sizeof(DIR))) == NULL) {
>  		close (fd);
>  		return NULL;
>  	}
> -- 
> 2.16.4

-- 
Corinna Vinschen
Cygwin Maintainer
Red Hat

signature.asc (application/pgp-signature, 833 B)