| Message ID | 1507723079-3430-1-git-send-email-volodymyr_babchuk@epam.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
>>> On 11.10.17 at 13:57, <volodymyr_babchuk@epam.com> wrote: > +/* Compound literals are supported in C99 and later. */ > +#if (defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ > + defined (__GNUC__) Strictly speaking the comment above is now stale. Also please don't put a space between "defined" and the opening parenthesis. If you check, the only two other such instances throughout the public headers are two ARM conditionals. And then the whole thing can be made fit on one line: #if defined(__STDC_VERSION__) ? __STDC_VERSION__ >= 199901L : defined(__GNUC__) > +#define XEN_DEFINE_UUID(a, b, c, d, e1, e2, e3, e4, e5, e6) \ > + ((xen_uuid_t)XEN_DEFINE_UUID_(a, b, c, d, e1, e2, e3, e4, e5, e6)) > +#else > +#define XEN_DEFINE_UUID(a, b, c, d, e1, e2, e3, e4, e5, e6) \ > + XEN_DEFINE_UUID_(a, b, c, d, e1, e2, e3, e4, e5, e6) > +#endif /* defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L */ Same for the comment here. I'd suggest either dropping it altogether or shortening it (e.g. /* __STDC_VERSION__ / __GNUC__ */) All of these adjustments ought to be doable while committing. With them done Acked-by: Jan Beulich <jbeulich@suse.com> Jan
On Wed, Oct 11, 2017 at 02:57:59PM +0300, Volodymyr Babchuk wrote: > Added type xen_uuid_t. This type represents UUID as an array of 16 > bytes in big endian format. > > Added macro XEN_DEFINE_UUID that constructs UUID in the usual way: > > XEN_DEFINE_UUID(0x00112233, 0x4455, 0x6677, 0x8899, > 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff) > > will construct UUID 00112233-4455-6677-8899-aabbccddeeff presented as > {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, > 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff} > > NB: We define a new structure here rather than re-using EFI_GUID. > EFI_GUID uses a Microsoft-style encoding which, among other things, > mixes little-endian and big-endian. The structure defined in this > patch, unlike EFI_GUID, is compatible with the Linux kernel and libuuid. > > Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/xen/include/public/xen.h b/xen/include/public/xen.h index 2ac6b1e..e7129fd 100644 --- a/xen/include/public/xen.h +++ b/xen/include/public/xen.h @@ -930,6 +930,39 @@ __DEFINE_XEN_GUEST_HANDLE(uint16, uint16_t); __DEFINE_XEN_GUEST_HANDLE(uint32, uint32_t); __DEFINE_XEN_GUEST_HANDLE(uint64, uint64_t); +typedef struct { + uint8_t a[16]; +} xen_uuid_t; + +/* + * XEN_DEFINE_UUID(0x00112233, 0x4455, 0x6677, 0x8899, + * 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff) + * will construct UUID 00112233-4455-6677-8899-aabbccddeeff presented as + * {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, + * 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff}; + * + * NB: This is compatible with Linux kernel and with libuuid, but it is not + * compatible with Microsoft, as they use mixed-endian encoding (some + * components are little-endian, some are big-endian). + */ +#define XEN_DEFINE_UUID_(a, b, c, d, e1, e2, e3, e4, e5, e6) \ + {{((a) >> 24) & 0xFF, ((a) >> 16) & 0xFF, \ + ((a) >> 8) & 0xFF, ((a) >> 0) & 0xFF, \ + ((b) >> 8) & 0xFF, ((b) >> 0) & 0xFF, \ + ((c) >> 8) & 0xFF, ((c) >> 0) & 0xFF, \ + ((d) >> 8) & 0xFF, ((d) >> 0) & 0xFF, \ + e1, e2, e3, e4, e5, e6}} + +/* Compound literals are supported in C99 and later. */ +#if (defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ + defined (__GNUC__) +#define XEN_DEFINE_UUID(a, b, c, d, e1, e2, e3, e4, e5, e6) \ + ((xen_uuid_t)XEN_DEFINE_UUID_(a, b, c, d, e1, e2, e3, e4, e5, e6)) +#else +#define XEN_DEFINE_UUID(a, b, c, d, e1, e2, e3, e4, e5, e6) \ + XEN_DEFINE_UUID_(a, b, c, d, e1, e2, e3, e4, e5, e6) +#endif /* defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L */ + #endif /* !__ASSEMBLY__ */ /* Default definitions for macros used by domctl/sysctl. */
Added type xen_uuid_t. This type represents UUID as an array of 16 bytes in big endian format. Added macro XEN_DEFINE_UUID that constructs UUID in the usual way: XEN_DEFINE_UUID(0x00112233, 0x4455, 0x6677, 0x8899, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff) will construct UUID 00112233-4455-6677-8899-aabbccddeeff presented as {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff} NB: We define a new structure here rather than re-using EFI_GUID. EFI_GUID uses a Microsoft-style encoding which, among other things, mixes little-endian and big-endian. The structure defined in this patch, unlike EFI_GUID, is compatible with the Linux kernel and libuuid. Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com> --- * Added check `|| defined(__GNUC__) to #if (defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) --- xen/include/public/xen.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+)