Re: [Qemu-devel] [PATCH 09/13] 9p: darwin: Provide a compatibility definition for XATTR_SIZE_MAX

[Keno Fischer]

> > +#if defined(CONFIG_DARWIN) && !defined(XATTR_SIZE_MAX)
> > +/* Darwin doesn't seem to define a maximum xattr size in its user
> > +   user space header, but looking at the kernel source, HFS supports
> > +   up to INT32_MAX, so use that as the maximum.
> > +*/
> > +#define XATTR_SIZE_MAX INT32_MAX
> > +#endif
>
> Do we really need the CONFIG_DARWIN part of this check?

Right now this code only runs on Linux (and Darwin after this series).
On Linux it's always defined,
but I'd rather this code give an error when somebody tries to port it
to a new OS than have it
silently use an incorrect value. The ` !defined(XATTR_SIZE_MAX)` is
just there in case Apple ever
decides to define it in their headers. I can remove that part if you
would prefer.

Re: [Qemu-devel] [PATCH 09/13] 9p: darwin: Provide a compatibility definition for XATTR_SIZE_MAX

[Peter Maydell]

On 26 May 2018 at 06:23,   wrote:
> From: Keno Fischer 
>
> Signed-off-by: Keno Fischer 
> ---
>  hw/9pfs/9p.c | 7 +++
>  1 file changed, 7 insertions(+)
>
> diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> index f5f00aa..4ae4da6 100644
> --- a/hw/9pfs/9p.c
> +++ b/hw/9pfs/9p.c
> @@ -3351,6 +3351,13 @@ out_nofid:
>  v9fs_string_free();
>  }
>
> +#if defined(CONFIG_DARWIN) && !defined(XATTR_SIZE_MAX)
> +/* Darwin doesn't seem to define a maximum xattr size in its user
> +   user space header, but looking at the kernel source, HFS supports
> +   up to INT32_MAX, so use that as the maximum.
> +*/
> +#define XATTR_SIZE_MAX INT32_MAX
> +#endif

Do we really need the CONFIG_DARWIN part of this check?

thanks
-- PMM

[Qemu-devel] [PATCH 09/13] 9p: darwin: Provide a compatibility definition for XATTR_SIZE_MAX

[keno]

From: Keno Fischer 

Signed-off-by: Keno Fischer 
---
 hw/9pfs/9p.c | 7 +++
 1 file changed, 7 insertions(+)

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index f5f00aa..4ae4da6 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -3351,6 +3351,13 @@ out_nofid:
 v9fs_string_free();
 }
 
+#if defined(CONFIG_DARWIN) && !defined(XATTR_SIZE_MAX)
+/* Darwin doesn't seem to define a maximum xattr size in its user
+   user space header, but looking at the kernel source, HFS supports
+   up to INT32_MAX, so use that as the maximum.
+*/
+#define XATTR_SIZE_MAX INT32_MAX
+#endif
 static void coroutine_fn v9fs_xattrcreate(void *opaque)
 {
 int flags;
-- 
2.8.1