Re: [PATCH] hvm: Correct RTC time offset update error due to tm->tm_year

[ANNIE LI <annie.li@oracle.com>]

On 2012-2-21 7:54, Zhang, Yang Z wrote:
>> -----Original Message-----
>> From: young zhang [mailto:young.zhang.free@gmail.com]
>> Sent: Monday, February 20, 2012 11:04 PM
>> To: Zhang, Yang Z
>> Cc: ANNIE LI; xen-devel@lists.xensource.com; Kurt Hackel; Dan Magenheimer;
>> Konrad Rzeszutek Wilk
>> Subject: Re: [Xen-devel] [PATCH] hvm: Correct RTC time offset update error due
>> to tm->tm_year
>>
>> The mktime which used in xen is different from standard C. I think the best way is
>> change it same as normal mktime, or else, other people will make the same
>> mistake too.
> yes. The name will mislead the people who not look into the code, including me. :)

I compared the mktime of xen with mktime of linux. The code is almost 
the same, I do not understand why xen requires the input year is 
tm->tm_year, not tm->tm_year+1900. Am I missing somthing?

See following diff file which is created between mktime of linux and 
mktime of xen, (I did some tab/space format changes for comparison)

diff linux-mktime.c xen-mktime.c
2,4c2,4
< mktime(const unsigned int year0, const unsigned int mon0,
<       const unsigned int day, const unsigned int hour,
<       const unsigned int min, const unsigned int sec)
---
 > mktime (unsigned int year, unsigned int mon,
 >       unsigned int day, unsigned int hour,
 >       unsigned int min, unsigned int sec)
6,8c6
<       unsigned int mon = mon0, year = year0;
<
<       /* 1..12 -> 11,12,1..10 */
---
 >       /* 1..12 -> 11,12,1..10: put Feb last since it has a leap day. */
10c8
<               mon += 12;      /* Puts Feb last since it has leap day */
---
 >               mon += 12;
21d18
<

Thanks
Annie
>
> best regards
> yang
>
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