diff options
Diffstat (limited to 'pcilib/timing.h')
-rw-r--r-- | pcilib/timing.h | 55 |
1 files changed, 52 insertions, 3 deletions
diff --git a/pcilib/timing.h b/pcilib/timing.h index 630df44..b8df7c3 100644 --- a/pcilib/timing.h +++ b/pcilib/timing.h @@ -8,14 +8,63 @@ extern "C" { #endif + +/** + * Add the specified number of microseconds to the time stored in \p tv + * @param[in,out] tv - timestamp + * @param[in] timeout - number of microseconds to add + * @return - error code or 0 for correctness + */ int pcilib_add_timeout(struct timeval *tv, pcilib_timeout_t timeout); + +/** + * Computes the deadline by adding the specified number of microseconds to the current timestamp + * @param[out] tv - the deadline + * @param[in] timeout - number of microseconds to add + * @return - error code or 0 for correctness + */ int pcilib_calc_deadline(struct timeval *tv, pcilib_timeout_t timeout); -int pcilib_check_deadline(struct timeval *tve, pcilib_timeout_t timeout); -pcilib_timeout_t pcilib_calc_time_to_deadline(struct timeval *tve); + +/** + * Check if we are within \p timeout microseconds before the specified deadline or already past it + * @param[in] tv - the deadline + * @param[in] timeout - maximum number of microseconds before deadline + * @return - 1 if we are within \p timeout microseconds before deadline or past it, 0 - otherwise + */ +int pcilib_check_deadline(struct timeval *tv, pcilib_timeout_t timeout); + +/** + * Compute the remaining time to deadline + * @param[in] tv - the deadline + * @return - number of microseconds until deadline or 0 if we are already past it + */ +pcilib_timeout_t pcilib_calc_time_to_deadline(struct timeval *tv); + +/** + * Executes sleep until the specified deadline + * Real-time capabilities are not used. TThe sleep could wake slightly after the specified deadline. + * @param[in] tv - the deadline + * @return - error code or 0 for correctness + */ int pcilib_sleep_until_deadline(struct timeval *tv); -int pcilib_timecmp(struct timeval *tv1, struct timeval *tv2); + +/** + * Computes the number of microseconds between 2 timestamps. + * This function expects that \p tve is after \p tvs. + * @param[in] tve - the end of the time interval + * @param[in] tvs - the beginning of the time interval + * @return - number of microseconds between two timestamps + */ pcilib_timeout_t pcilib_timediff(struct timeval *tve, struct timeval *tvs); +/** + * Compares two timestamps + * @param[in] tv1 - the first timestamp + * @param[in] tv2 - the second timestamp + * @return - 0 if timestamps are equal, 1 if the first timestamp is after the second, or -1 if the second is after the first. + */ +int pcilib_timecmp(struct timeval *tv1, struct timeval *tv2); + #ifdef __cplusplus } |