Re: [PATCH v2 07/15] qga: use qemu_open_cloexec() for safe_open_or_create()

[Markus Armbruster]

marcandre.lureau@redhat.com writes:

> From: Marc-André Lureau <marcandre.lureau@redhat.com>
>
> The function takes care of setting CLOEXEC, and reporting error.
>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  qga/commands-posix.c | 11 +++--------
>  1 file changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 0ef049650e31..8ebc327c5e02 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -370,21 +370,16 @@ safe_open_or_create(const char *path, const char *mode, 
> Error **errp)
>       * open() is decisive and its third argument is ignored, and the second
>       * open() and the fchmod() are never called.
>       */
> -    fd = open(path, oflag | ((oflag & O_CREAT) ? O_EXCL : 0), 0);
> +    fd = qemu_open_cloexec(path, oflag | ((oflag & O_CREAT) ? O_EXCL : 0), 
> 0, errp);
>      if (fd == -1 && errno == EEXIST) {
> +        g_clear_pointer(errp, error_free);

Aha, this is where you really need ERRP_GUARD().

Elsewhere, we use

           error_free(errp);
           errp = NULL;

If one of these two ways is superior, we should use the superior one
everywhere.

If it's a wash, we should stick to the prevalent way.

>          oflag &= ~(unsigned)O_CREAT;
> -        fd = open(path, oflag);
> +        fd = qemu_open_cloexec(path, oflag, 0, errp);
>      }
>      if (fd == -1) {
> -        error_setg_errno(errp, errno,
> -                         "failed to open file '%s' "
> -                         "(mode: '%s')",
> -                         path, mode);

This changes the error message, doesn't it?

Not an objection, just something that might be worth noting in the
commit message.

>          goto end;
>      }
>  
> -    qemu_set_cloexec(fd);
> -
>      if ((oflag & O_CREAT) && fchmod(fd, DEFAULT_NEW_FILE_MODE) == -1) {
>          error_setg_errno(errp, errno,
>                           "failed to set permission 0%03o on new file '%s' 
> (mode: '%s')",