Re: [PATCH] util/cutils: Expand do_strtosz parsing precision to 64 bits

[Markus Armbruster]

Tao Xu <address@hidden> writes:

> On 12/18/2019 9:33 AM, Tao Xu wrote:
>> On 12/17/2019 6:25 PM, Markus Armbruster wrote:
[...]
>>> Also fun: for "0123", we use uint64_t 83, not double 123.0.  But for
>>> "0123.", we use 123.0, not 83.
>>>
>>> Do we really want to accept octal and hexadecimal integers?
>>>
>>
>> Thank you for reminding me. Octal and hexadecimal may bring more
>> confusion. I will use qemu_strtou64(nptr, &suffixu, 10, &valu) and
>> add test for input like "0123".
>>
>
> Hi Markus,
>
> After I use qemu_strtou64(nptr, &suffixu, 10, &valu), it cause another
> question. Because qemu_strtod_finite support hexadecimal input, so in
> this situation, it will parsed as double. It will also let large
> hexadecimal integers be rounded. So there may be two solution:
>
> 1: use qemu_strtou64(nptr, &suffixu, 0, &valu) and parse octal as
> decimal. This will keep hexadecimal valid as now.
>
> "0123" --> 123; "0x123" --> 291

How would you make qemu_strtou64() parse octal as decimal?

> 2: use qemu_strtou64(nptr, &suffixu, 10, &valu) and reject octal and
> decimal.
>
> "0123" --> Error; "0x123" --> Error

How would you reject the 0x prefix?