Re: [Qemu-devel] [PATCH v3 4/7] range: add some more functions

[David Hildenbrand]

On 01.11.18 11:00, Igor Mammedov wrote:
> On Tue, 23 Oct 2018 17:23:03 +0200
> David Hildenbrand <address@hidden> wrote:
> 
>> Add some more functions that will be used in memory-device context.
>>
>> range_init(): Init using lower bound and size, check for validity
>> range_init_nofail(): Init using lower bound and size, validity asserted
>> range_size(): Extract the size of a range
>> range_overlaps_range(): Check for overlaps of two ranges
>> range_contains_range(): Check if one range is contained in the other
>>
>> Signed-off-by: David Hildenbrand <address@hidden>
>> ---
>>  include/qemu/range.h | 62 ++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 62 insertions(+)
>>
>> diff --git a/include/qemu/range.h b/include/qemu/range.h
>> index 7e75f4e655..ba606c6bc0 100644
>> --- a/include/qemu/range.h
>> +++ b/include/qemu/range.h
>> @@ -112,6 +112,68 @@ static inline uint64_t range_upb(Range *range)
>>      return range->upb;
>>  }
>>  
>> +/*
>> + * Initialize @range to span the interval address@hidden,@lob + @size - 1].
>> + * @size may be 0. If the range would overflow, returns -ERANGE, otherwise
>> + * 0.
>> + */
>> +static inline int QEMU_WARN_UNUSED_RESULT range_init(Range *range, uint64_t 
>> lob,
>> +                                                     uint64_t size)
>> +{
>> +    if (lob + size < lob) {
>> +        return -ERANGE;
>> +    }
>> +    range->lob = lob;
>> +    range->upb = lob + size - 1;
>> +    range_invariant(range);
>> +    return 0;
>> +}
>> +
>> +/*
>> + * Initialize @range to span the interval address@hidden,@lob + @size - 1].
>> + * @size may be 0. Range must not overflow.
>> + */
>> +static inline void range_init_nofail(Range *range, uint64_t lob, uint64_t 
>> size)
>> +{
>> +    range->lob = lob;
>> +    range->upb = lob + size - 1;
>> +    range_invariant(range);
>> +}
>> +
>> +/*
>> + * Get the size of @range.
>> + */
>> +static inline uint64_t range_size(const Range *range)
>> +{
>> +    return range->upb - range->lob + 1;
>> +}
>> +
>> +/*
>> + * Check if @range1 overlaps with @range2. If one of the ranges is empty,
>> + * the result is always "false".
>> + */
>> +static inline bool range_overlaps_range(const Range *range1,
>> +                                        const Range *range2)
>> +{
>> +    if (range_is_empty(range1) || range_is_empty(range2)) {
> compilation fails with:
>  "error: passing argument 1 of ‘range_is_empty’ discards ‘const’ qualifier 
> from pointer target type [-Werror]"
> 
> the same for range_invariant,
> following should fix issues:

I guess you missed patch #3.


-- 

Thanks,

David / dhildenb