Lazy time test macro

timetest.c

#define TIMETEST(name, content) struct timeval tval_before_##name, tval_after_##name, tval_result_##name; \
    gettimeofday(&tval_before_##name, NULL); \
    content \
    gettimeofday(&tval_after_##name, NULL); \
    timersub(&tval_after_##name, &tval_before_##name, &tval_result_##name); \
    printf(#name " %ld.%06ld\n", (long int)tval_result_##name.tv_sec, (long int)tval_result_##name.tv_usec);