Get the modification time of a config file with a higher precision to fix cases when it's not reloaded after modification/replacement

[ilya071294]

The fix is needed to avoid potential problems in Firebird QA.

[aafemt]

Wouldn't it be better to make Windows version of getTime to return timespec and unify the rest of code?

Also it is simpler to use GetFileAttributesEx than FindFirstFile.

[ilya071294]

Wouldn't it be better to make Windows version of getTime to return timespec and unify the rest of code?

I can do that if conversion to timespec on every checkLoadConfig call is appropriate. @AlexPeshkoff What do you think?

Also it is simpler to use GetFileAttributesEx than FindFirstFile.

Done.

[aafemt]

I can do that if conversion to timespec on every checkLoadConfig call is appropriate.

IIRC this "conversion" is a couple of multiplication.

[dyemanov]

@AlexPeshkoff do you have any objections to this change?

[AlexPeshkoff]

Do something like this:
namespace Firebird {
class PreciseTime
{
public:
PreciseTime() : high(0), low(0) {}
#ifdef WIN_NT
PreciseTime(//Windows specific ctor
#else
PreciseTime(//Posix specific ctor
#endif

operator=(const PreciseTime&) = default;

private:
time_t high;
unsigned low;
};
} // namespace

Next:
Firebird::PreciseTime ConfigCache::File::getTime();

And return PreciseTime from that function - code around remains as clear as it was before.