int main(int argc, char **argv) {
int four[4];
int five[5];
uint32_t bitset = 0;
grpc_test_init(argc, argv);
GPR_ASSERT(GPR_MIN(1, 2) == 1);
GPR_ASSERT(GPR_MAX(1, 2) == 2);
GPR_ASSERT(GPR_MIN(2, 1) == 1);
GPR_ASSERT(GPR_MAX(2, 1) == 2);
GPR_ASSERT(GPR_CLAMP(1, 0, 2) == 1);
GPR_ASSERT(GPR_CLAMP(0, 0, 2) == 0);
GPR_ASSERT(GPR_CLAMP(2, 0, 2) == 2);
GPR_ASSERT(GPR_CLAMP(-1, 0, 2) == 0);
GPR_ASSERT(GPR_CLAMP(3, 0, 2) == 2);
GPR_ASSERT(GPR_ROTL((uint32_t)0x80000001, 1) == 3);
GPR_ASSERT(GPR_ROTR((uint32_t)0x80000001, 1) == 0xc0000000);
GPR_ASSERT(GPR_ARRAY_SIZE(four) == 4);
GPR_ASSERT(GPR_ARRAY_SIZE(five) == 5);
GPR_ASSERT(GPR_BITCOUNT((1u << 31) - 1) == 31);
GPR_ASSERT(GPR_BITCOUNT(1u << 3) == 1);
GPR_ASSERT(GPR_BITCOUNT(0) == 0);
GPR_ASSERT(GPR_BITSET(&bitset, 3) == 8);
GPR_ASSERT(GPR_BITCOUNT(bitset) == 1);
GPR_ASSERT(GPR_BITGET(bitset, 3) == 1);
GPR_ASSERT(GPR_BITSET(&bitset, 1) == 10);
GPR_ASSERT(GPR_BITCOUNT(bitset) == 2);
GPR_ASSERT(GPR_BITCLEAR(&bitset, 3) == 2);
GPR_ASSERT(GPR_BITCOUNT(bitset) == 1);
GPR_ASSERT(GPR_BITGET(bitset, 3) == 0);
return 0;
}
gpr_timespec gpr_backoff_step(gpr_backoff *backoff, gpr_timespec now) {
double new_timeout_millis =
backoff->multiplier * (double)backoff->current_timeout_millis;
double jitter_range = backoff->jitter * new_timeout_millis;
double jitter =
(2 * generate_uniform_random_number(&backoff->rng_state) - 1) *
jitter_range;
backoff->current_timeout_millis =
GPR_CLAMP((int64_t)(new_timeout_millis + jitter),
backoff->min_timeout_millis, backoff->max_timeout_millis);
return gpr_time_add(
now, gpr_time_from_millis(backoff->current_timeout_millis, GPR_TIMESPAN));
}
static void push_setting(grpc_chttp2_transport *t, grpc_chttp2_setting_id id,
gpr_uint32 value) {
const grpc_chttp2_setting_parameters *sp =
&grpc_chttp2_settings_parameters[id];
gpr_uint32 use_value = GPR_CLAMP(value, sp->min_value, sp->max_value);
if (use_value != value) {
gpr_log(GPR_INFO, "Requested parameter %s clamped from %d to %d", sp->name,
value, use_value);
}
if (use_value != t->global.settings[GRPC_LOCAL_SETTINGS][id]) {
t->global.settings[GRPC_LOCAL_SETTINGS][id] = use_value;
t->global.dirtied_local_settings = 1;
}
}
static double threshold_for_count_below(gpr_histogram *h, double count_below) {
double count_so_far;
double lower_bound;
double upper_bound;
size_t lower_idx;
size_t upper_idx;
if (h->count == 0) {
return 0.0;
}
if (count_below <= 0) {
return h->min_seen;
}
if (count_below >= h->count) {
return h->max_seen;
}
/* find the lowest bucket that gets us above count_below */
count_so_far = 0.0;
for (lower_idx = 0; lower_idx < h->num_buckets; lower_idx++) {
count_so_far += h->buckets[lower_idx];
if (count_so_far >= count_below) {
break;
}
}
if (count_so_far == count_below) {
/* this bucket hits the threshold exactly... we should be midway through
any run of zero values following the bucket */
for (upper_idx = lower_idx + 1; upper_idx < h->num_buckets; upper_idx++) {
if (h->buckets[upper_idx]) {
break;
}
}
return (bucket_start(h, (double)lower_idx) +
bucket_start(h, (double)upper_idx)) /
2.0;
} else {
/* treat values as uniform throughout the bucket, and find where this value
should lie */
lower_bound = bucket_start(h, (double)lower_idx);
upper_bound = bucket_start(h, (double)(lower_idx + 1));
return GPR_CLAMP(upper_bound -
(upper_bound - lower_bound) *
(count_so_far - count_below) /
h->buckets[lower_idx],
h->min_seen, h->max_seen);
}
}
double grpc_pid_controller_update(grpc_pid_controller *pid_controller,
double error, double dt) {
/* integrate error using the trapezoid rule */
pid_controller->error_integral +=
dt * (pid_controller->last_error + error) * 0.5;
pid_controller->error_integral = GPR_CLAMP(
pid_controller->error_integral, -pid_controller->args.integral_range,
pid_controller->args.integral_range);
double diff_error = (error - pid_controller->last_error) / dt;
/* calculate derivative of control value vs time */
double dc_dt = pid_controller->args.gain_p * error +
pid_controller->args.gain_i * pid_controller->error_integral +
pid_controller->args.gain_d * diff_error;
/* and perform trapezoidal integration */
double new_control_value = pid_controller->last_control_value +
dt * (pid_controller->last_dc_dt + dc_dt) * 0.5;
new_control_value =
GPR_CLAMP(new_control_value, pid_controller->args.min_control_value,
pid_controller->args.max_control_value);
pid_controller->last_error = error;
pid_controller->last_dc_dt = dc_dt;
pid_controller->last_control_value = new_control_value;
return new_control_value;
}
/* bounds checked version of the above */
static size_t bucket_for(gpr_histogram *h, double x) {
size_t bucket = bucket_for_unchecked(h, GPR_CLAMP(x, 0, h->max_possible));
GPR_ASSERT(bucket < h->num_buckets);
return bucket;
}
