Timing

Data Structures
struct	mbedtls_timing_hr_time
	timer structure More...
struct	mbedtls_timing_delay_context
	Context for mbedtls_timing_set/get_delay() More...

Typedefs
typedef struct mbedtls_timing_delay_context	mbedtls_timing_delay_context
	Context for mbedtls_timing_set/get_delay() More...

Functions
unsigned long	mbedtls_timing_hardclock (void)
	Return the CPU cycle counter value. More...
unsigned long	mbedtls_timing_get_timer (struct mbedtls_timing_hr_time *val, int reset)
	Return the elapsed time in milliseconds. More...
void	mbedtls_set_alarm (int seconds)
	Setup an alarm clock. More...
void	mbedtls_timing_set_delay (void *data, uint32_t int_ms, uint32_t fin_ms)
	Set a pair of delays to watch (See mbedtls_timing_get_delay().) More...
int	mbedtls_timing_get_delay (void *data)
	Get the status of delays (Memory helper: number of delays passed.) More...

Detailed Description

Typedef Documentation

mbedtls_timing_delay_context

typedef struct mbedtls_timing_delay_context mbedtls_timing_delay_context

Context for mbedtls_timing_set/get_delay()

Function Documentation

mbedtls_timing_hardclock()

unsigned long mbedtls_timing_hardclock

(

void

)

Return the CPU cycle counter value.

Warning

This is only a best effort! Do not rely on this! In particular, it is known to be unreliable on virtual machines.

Note

This value starts at an unspecified origin and may wrap around.

mbedtls_timing_get_timer()

unsigned long mbedtls_timing_get_timer	(	struct mbedtls_timing_hr_time *	val,
		int	reset
	)

Return the elapsed time in milliseconds.

Parameters

val	points to a timer structure
reset	If 0, query the elapsed time. Otherwise (re)start the timer.

Returns

Elapsed time since the previous reset in ms. When restarting, this is always 0.

Note

To initialize a timer, call this function with reset=1.

            Determining the elapsed time and resetting the timer is not
            atomic on all platforms, so after the sequence
            `{ get_timer(1); ...; time1 = get_timer(1); ...; time2 =
            get_timer(0) }` the value time1+time2 is only approximately
            the delay since the first reset.

mbedtls_set_alarm()

void mbedtls_set_alarm

(

int

seconds

)

Setup an alarm clock.

Parameters

seconds

delay before the "mbedtls_timing_alarmed" flag is set (must be >=0)

Warning

Only one alarm at a time is supported. In a threaded context, this means one for the whole process, not one per thread.

mbedtls_timing_set_delay()

void mbedtls_timing_set_delay	(	void *	data,
		uint32_t	int_ms,
		uint32_t	fin_ms
	)

Set a pair of delays to watch (See mbedtls_timing_get_delay().)

Parameters

data	Pointer to timing data. Must point to a valid mbedtls_timing_delay_context struct.
int_ms	First (intermediate) delay in milliseconds. The effect if int_ms > fin_ms is unspecified.
fin_ms	Second (final) delay in milliseconds. Pass 0 to cancel the current delay.

Note

To set a single delay, either use mbedtls_timing_set_timer directly or use this function with int_ms == fin_ms.

mbedtls_timing_get_delay()

int mbedtls_timing_get_delay

(

void *

data

)

Get the status of delays (Memory helper: number of delays passed.)

Parameters

data	Pointer to timing data Must point to a valid mbedtls_timing_delay_context struct.

Returns

-1 if cancelled (fin_ms = 0), 0 if none of the delays are passed, 1 if only the intermediate delay is passed, 2 if the final delay is passed.