static grpc_resolver *dns_create(grpc_resolver_args *args,
const char *default_port) {
if (0 != strcmp(args->uri->authority, "")) {
gpr_log(GPR_ERROR, "authority based dns uri's not supported");
return NULL;
}
// Get name from args.
const char *path = args->uri->path;
if (path[0] == '/') ++path;
// Get proxy name, if any.
char *proxy_name = grpc_get_http_proxy_server();
// Create resolver.
dns_resolver *r = gpr_malloc(sizeof(dns_resolver));
memset(r, 0, sizeof(*r));
gpr_mu_init(&r->mu);
grpc_resolver_init(&r->base, &dns_resolver_vtable);
r->name_to_resolve = proxy_name == NULL ? gpr_strdup(path) : proxy_name;
r->default_port = gpr_strdup(default_port);
r->channel_args = grpc_channel_args_copy(args->args);
gpr_backoff_init(&r->backoff_state, GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS,
GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER,
GRPC_DNS_RECONNECT_JITTER,
GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
return &r->base;
}
static grpc_resolver *dns_create(grpc_resolver_args *args,
const char *default_port,
const char *lb_policy_name) {
if (0 != strcmp(args->uri->authority, "")) {
gpr_log(GPR_ERROR, "authority based dns uri's not supported");
return NULL;
}
// Get name from args.
const char *path = args->uri->path;
if (path[0] == '/') ++path;
// Get proxy name, if any.
char *proxy_name = grpc_get_http_proxy_server();
// Create resolver.
dns_resolver *r = gpr_malloc(sizeof(dns_resolver));
memset(r, 0, sizeof(*r));
gpr_ref_init(&r->refs, 1);
gpr_mu_init(&r->mu);
grpc_resolver_init(&r->base, &dns_resolver_vtable);
r->target_name = gpr_strdup(path);
r->name_to_resolve = proxy_name == NULL ? gpr_strdup(path) : proxy_name;
r->default_port = gpr_strdup(default_port);
gpr_backoff_init(&r->backoff_state, BACKOFF_MULTIPLIER, BACKOFF_JITTER,
BACKOFF_MIN_SECONDS * 1000, BACKOFF_MAX_SECONDS * 1000);
r->lb_policy_name = gpr_strdup(lb_policy_name);
return &r->base;
}
static void test_constant_backoff(void) {
gpr_backoff backoff;
gpr_backoff_init(&backoff, 1.0, 0.0, 1000, 1000);
gpr_timespec now = gpr_time_0(GPR_TIMESPAN);
gpr_timespec next = gpr_backoff_begin(&backoff, now);
GPR_ASSERT(gpr_time_to_millis(gpr_time_sub(next, now)) == 1000);
for (int i = 0; i < 10000; i++) {
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_to_millis(gpr_time_sub(next, now)) == 1000);
now = next;
}
}
static void test_no_jitter_backoff(void) {
gpr_backoff backoff;
gpr_backoff_init(&backoff, 2.0, 0.0, 1, 513);
gpr_timespec now = gpr_time_0(GPR_TIMESPAN);
gpr_timespec next = gpr_backoff_begin(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(3, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(7, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(15, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(31, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(63, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(127, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(255, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(511, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1023, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1536, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(2049, GPR_TIMESPAN), next) == 0);
now = next;
next = gpr_backoff_step(&backoff, now);
GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(2562, GPR_TIMESPAN), next) == 0);
}
