[ovs-dev] [PATCH v2] packet: proper return type for vlan_tci_to_pcp()

[Shu Shen]

Sorry I missed the list in my reply.

On Sat, Jan 14, 2017 at 9:59 AM, Shu Shen <shu.shen at gmail.com> wrote:
> The main change of this patch is in lib/packets.h, where the return type of
> vlan_tci_to_pcp() and vlan_tci_to_cfi() are changed from int to uint8_t.
>
> Changes to the format specifiers are for portability to mac OS and
> consistency use of PRIu* specifiers.
>
> On Sat, Jan 14, 2017 at 8:47 AM, Ben Pfaff <blp at ovn.org> wrote:
>> On Fri, Jan 13, 2017 at 02:04:38PM -0800, Shu Shen wrote:
>>> The return type of vlan_tci_to_pcp() was int where it's expected to be
>>> uint8_t and causing implicit truncation when the function is used. On
>>> some platforms such as macOS, where PRIu8 is defined as "hhx" and no
>>> promotion of short to int is done, the compiler might throw out Wformat
>>> message for ds_put_format() calls on the returns value of
>>> vlan_tci_to_pcp().
>>>
>>> vlan_tci_to_cfi() is also fixed with uint8_t as return type although the
>>> function is not currently being used anywhere.
>>>
>>> Format strings in ds_put_format() for printing out returned values from
>>> vlan_tci_to_pcp() were updated to ensure PRIu8 or PRIx8 are used for
>>> portability.
>>>
>>> Signed-off-by: Shu Shen <shu.shen at gmail.com>
>>> ---
>>>
>>> v2: Fixed typoes for uint8_t in commit message
>>
>> This one doesn't really make sense to me.  This patch only changes two
>> format specifiers away from %d or %x, which are both correct format
>> specifiers for "int".  Can you explain?
>>
>> Thanks,
>>
>> Ben.