On 05/28/2014 04:46 AM, Laine Stump wrote:
The original version of virTimeLocalOffsetFromUTC() would fail for certain times of the day if daylight savings time was active. This could most easily be seen by uncommenting the TEST_LOCALOFFSET() cases that include a DST setting.
src/util/virtime.c | 3 +++ tests/virtimetest.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 56 insertions(+), 8 deletions(-)
diff --git a/src/util/virtime.c b/src/util/virtime.c index 3a56400..c69dff1 100644 --- a/src/util/virtime.c +++ b/src/util/virtime.c @@ -377,6 +377,9 @@ virTimeLocalOffsetFromUTC(long *offset) return -1; }
+ /* tell mktime to figure out itself whether or not DST is in effect */ + gmtimeinfo.tm_isdst = -1;
As pointed out by Wangrui, you also need to fix the bogus reference to localtime_r() in the comments at the start of the function. ACK with that change; worth having in 1.2.5. The rest of what follows is up to you if you ignore it.
+ +/* return true if the date is Jan 1 or Dec 31 (localtime) */ +static bool +IsJan1OrDec31(void)
Function names are usually camelCase, not StudlyCaps (s/Is/is/). Bikeshedding: maybe name it isNearYearEnd()?
+ + if (!IsJan1OrDec31()) { + /* experiments have shown that the following tests will fail + * during certain hours of Dec 31 or Jan 1 (depending on the + * TZ setting in the shell running the test, but in general + * for a period that apparently starts at 00:00:00 UTC Jan 1 + * and continues for 1 - 2 hours). We've determined this is + * due to our inability to specify a timezone with DST on/off + * settings that make it truly *always* on DST - i.e. it is a + * failing of the test data, *not* of the function we are + * testing. So to test as much as possible, we still run these + * tests, except on Dec 31 and Jan 1.
Awesome comment; thanks :) -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org