Use monotonic clock to prevent timing issues
This patch replaces the gettimeofday()/timeval-system with
uses of clock_gettime() with a monolithic clock and timespec-structs.
gettimeofday() is not accurate and prone to jumps and POSIX.1-2008
marks it as obsolete. Read more here [0].
The patch should speak for itself and decreases the binary
size for me by almost 200K(!).
[0]: http://blog.habets.pp.se/2010/09/gettimeofday-should-never-be-used-to-measure-time
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>