[PATCH v2 1/2] uuid: Add a glue layer macros for raw buffers

[PATCH v2 1/2] uuid: Add a glue layer macros for raw buffers

[Andy Shevchenko]

When the ID comes from or we would like to pass it to a raw buffer,
the casting is needed.

Instead of doing it each time, provide a helpful set of macros.

Suggested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 include/linux/uuid.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/linux/uuid.h b/include/linux/uuid.h
index d9c4a6cce3c2..917f1d4e5d44 100644
--- a/include/linux/uuid.h
+++ b/include/linux/uuid.h
@@ -51,11 +51,16 @@ static inline void guid_copy(guid_t *dst, const guid_t *src)
 	memcpy(dst, src, sizeof(guid_t));
 }
 
+#define guid_copy_from_raw(dst, src)	guid_copy(dst, (const guid_t *)src)
+#define guid_copy_to_raw(dst, src)	guid_copy((void *)dst, src)
+
 static inline bool guid_is_null(const guid_t *guid)
 {
 	return guid_equal(guid, &guid_null);
 }
 
+#define guid_is_null_raw(guid)		guid_is_null((const guid_t *)guid)
+
 static inline bool uuid_equal(const uuid_t *u1, const uuid_t *u2)
 {
 	return memcmp(u1, u2, sizeof(uuid_t)) == 0;
@@ -66,16 +71,24 @@ static inline void uuid_copy(uuid_t *dst, const uuid_t *src)
 	memcpy(dst, src, sizeof(uuid_t));
 }
 
+#define uuid_copy_from_raw(dst, src)	uuid_copy(dst, (const uuid_t *)src)
+#define uuid_copy_to_raw(dst, src)	uuid_copy((void *)dst, src)
+
 static inline bool uuid_is_null(const uuid_t *uuid)
 {
 	return uuid_equal(uuid, &uuid_null);
 }
 
+#define uuid_is_null_raw(uuid)		uuid_is_null((const uuid_t *)uuid)
+
 void generate_random_uuid(unsigned char uuid[16]);
 
 extern void guid_gen(guid_t *u);
 extern void uuid_gen(uuid_t *u);
 
+#define guid_gen_raw(guid)		guid_gen((guid_t *)guid)
+#define uuid_gen_raw(uuid)		uuid_gen((uuid_t *)uuid)
+
 bool __must_check uuid_is_valid(const char *uuid);
 
 extern const u8 guid_index[16];
-- 
2.20.1

Re: [PATCH v2 1/2] uuid: Add a glue layer macros for raw buffers

[Christoph Hellwig]

On Fri, Mar 29, 2019 at 11:26:43PM +0300, Andy Shevchenko wrote:
> When the ID comes from or we would like to pass it to a raw buffer,
> the casting is needed.

Something is missing in this sentence.

Re: [PATCH v2 1/2] uuid: Add a glue layer macros for raw buffers

[Andy Shevchenko]

On Wed, Apr 03, 2019 at 08:09:03PM +0200, Christoph Hellwig wrote:
> On Fri, Mar 29, 2019 at 11:26:43PM +0300, Andy Shevchenko wrote:
> > When the ID comes from or we would like to pass it to a raw buffer,
> > the casting is needed.
> 
> Something is missing in this sentence.

What I meant there is if we got a raw buffer, consider u8 * pointer to it, and
we would like to either take a UUID in binary form from it or pass it to that
buffer, we have to cast due to type inequivalence.

Can you suggest how to compress it nicely to few words?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 1/2] uuid: Add a glue layer macros for raw buffers

[Christoph Hellwig]

On Thu, Apr 04, 2019 at 11:45:26AM +0300, Andy Shevchenko wrote:
> On Wed, Apr 03, 2019 at 08:09:03PM +0200, Christoph Hellwig wrote:
> > On Fri, Mar 29, 2019 at 11:26:43PM +0300, Andy Shevchenko wrote:
> > > When the ID comes from or we would like to pass it to a raw buffer,
> > > the casting is needed.
> > 
> > Something is missing in this sentence.
> 
> What I meant there is if we got a raw buffer, consider u8 * pointer to it, and
> we would like to either take a UUID in binary form from it or pass it to that
> buffer, we have to cast due to type inequivalence.
> 
> Can you suggest how to compress it nicely to few words?

Well, the usual way is to memcpy it out, and I'm not sure how this
is so much better.  But maybe a detailed changelog that actuall parses
and properly typed inline functions might convince me :)