static grpc_resolver *dns_create(grpc_exec_ctx *exec_ctx,
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);
r->interested_parties = grpc_pollset_set_create();
if (args->pollset_set != NULL) {
grpc_pollset_set_add_pollset_set(exec_ctx, r->interested_parties,
args->pollset_set);
}
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;
}
void grpc_polling_entity_add_to_pollset_set(grpc_exec_ctx *exec_ctx,
grpc_polling_entity *pollent,
grpc_pollset_set *pss_dst) {
if (pollent->tag == POPS_POLLSET) {
GPR_ASSERT(pollent->pollent.pollset != NULL);
grpc_pollset_set_add_pollset(exec_ctx, pss_dst, pollent->pollent.pollset);
} else if (pollent->tag == POPS_POLLSET_SET) {
GPR_ASSERT(pollent->pollent.pollset_set != NULL);
grpc_pollset_set_add_pollset_set(exec_ctx, pss_dst,
pollent->pollent.pollset_set);
} else {
gpr_log(GPR_ERROR, "Invalid grpc_polling_entity tag '%d'", pollent->tag);
abort();
}
}
static void on_resolver_result_changed(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
channel_data *chand = arg;
grpc_lb_policy *lb_policy = NULL;
grpc_lb_policy *old_lb_policy;
grpc_mdstr_hash_table *method_params_table = NULL;
grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
bool exit_idle = false;
grpc_error *state_error = GRPC_ERROR_CREATE("No load balancing policy");
if (chand->resolver_result != NULL) {
grpc_lb_policy_args lb_policy_args;
lb_policy_args.args = chand->resolver_result;
lb_policy_args.client_channel_factory = chand->client_channel_factory;
// Find LB policy name.
const char *lb_policy_name = NULL;
const grpc_arg *channel_arg =
grpc_channel_args_find(lb_policy_args.args, GRPC_ARG_LB_POLICY_NAME);
if (channel_arg != NULL) {
GPR_ASSERT(channel_arg->type == GRPC_ARG_STRING);
lb_policy_name = channel_arg->value.string;
}
// Special case: If all of the addresses are balancer addresses,
// assume that we should use the grpclb policy, regardless of what the
// resolver actually specified.
channel_arg =
grpc_channel_args_find(lb_policy_args.args, GRPC_ARG_LB_ADDRESSES);
if (channel_arg != NULL) {
GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
grpc_lb_addresses *addresses = channel_arg->value.pointer.p;
bool found_backend_address = false;
for (size_t i = 0; i < addresses->num_addresses; ++i) {
if (!addresses->addresses[i].is_balancer) {
found_backend_address = true;
break;
}
}
if (!found_backend_address) {
if (lb_policy_name != NULL && strcmp(lb_policy_name, "grpclb") != 0) {
gpr_log(GPR_INFO,
"resolver requested LB policy %s but provided only balancer "
"addresses, no backend addresses -- forcing use of grpclb LB "
"policy",
lb_policy_name);
}
lb_policy_name = "grpclb";
}
}
// Use pick_first if nothing was specified and we didn't select grpclb
// above.
if (lb_policy_name == NULL) lb_policy_name = "pick_first";
lb_policy =
grpc_lb_policy_create(exec_ctx, lb_policy_name, &lb_policy_args);
if (lb_policy != NULL) {
GRPC_LB_POLICY_REF(lb_policy, "config_change");
GRPC_ERROR_UNREF(state_error);
state =
grpc_lb_policy_check_connectivity(exec_ctx, lb_policy, &state_error);
}
channel_arg =
grpc_channel_args_find(lb_policy_args.args, GRPC_ARG_SERVICE_CONFIG);
if (channel_arg != NULL) {
GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
method_params_table = grpc_method_config_table_convert(
(grpc_method_config_table *)channel_arg->value.pointer.p,
method_config_convert_value, &method_parameters_vtable);
}
grpc_channel_args_destroy(chand->resolver_result);
chand->resolver_result = NULL;
}
if (lb_policy != NULL) {
grpc_pollset_set_add_pollset_set(exec_ctx, lb_policy->interested_parties,
chand->interested_parties);
}
gpr_mu_lock(&chand->mu);
old_lb_policy = chand->lb_policy;
chand->lb_policy = lb_policy;
if (chand->method_params_table != NULL) {
grpc_mdstr_hash_table_unref(chand->method_params_table);
}
chand->method_params_table = method_params_table;
if (lb_policy != NULL) {
grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
NULL);
} else if (chand->resolver == NULL /* disconnected */) {
grpc_closure_list_fail_all(
&chand->waiting_for_config_closures,
GRPC_ERROR_CREATE_REFERENCING("Channel disconnected", &error, 1));
grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
NULL);
}
if (lb_policy != NULL && chand->exit_idle_when_lb_policy_arrives) {
GRPC_LB_POLICY_REF(lb_policy, "exit_idle");
exit_idle = true;
chand->exit_idle_when_lb_policy_arrives = false;
}
if (error == GRPC_ERROR_NONE && chand->resolver) {
set_channel_connectivity_state_locked(
exec_ctx, chand, state, GRPC_ERROR_REF(state_error), "new_lb+resolver");
if (lb_policy != NULL) {
watch_lb_policy(exec_ctx, chand, lb_policy, state);
}
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver, &chand->resolver_result,
&chand->on_resolver_result_changed);
gpr_mu_unlock(&chand->mu);
} else {
if (chand->resolver != NULL) {
grpc_resolver_shutdown(exec_ctx, chand->resolver);
GRPC_RESOLVER_UNREF(exec_ctx, chand->resolver, "channel");
chand->resolver = NULL;
}
grpc_error *refs[] = {error, state_error};
set_channel_connectivity_state_locked(
exec_ctx, chand, GRPC_CHANNEL_SHUTDOWN,
GRPC_ERROR_CREATE_REFERENCING("Got config after disconnection", refs,
GPR_ARRAY_SIZE(refs)),
"resolver_gone");
gpr_mu_unlock(&chand->mu);
}
if (exit_idle) {
grpc_lb_policy_exit_idle(exec_ctx, lb_policy);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "exit_idle");
}
if (old_lb_policy != NULL) {
grpc_pollset_set_del_pollset_set(
exec_ctx, old_lb_policy->interested_parties, chand->interested_parties);
GRPC_LB_POLICY_UNREF(exec_ctx, old_lb_policy, "channel");
}
if (lb_policy != NULL) {
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "config_change");
}
GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "resolver");
GRPC_ERROR_UNREF(state_error);
}
static void on_resolver_result_changed(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
channel_data *chand = arg;
grpc_lb_policy *lb_policy = NULL;
grpc_lb_policy *old_lb_policy;
grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
bool exit_idle = false;
grpc_error *state_error = GRPC_ERROR_CREATE("No load balancing policy");
if (chand->resolver_result != NULL) {
lb_policy = grpc_resolver_result_get_lb_policy(chand->resolver_result);
if (lb_policy != NULL) {
GRPC_LB_POLICY_REF(lb_policy, "channel");
GRPC_LB_POLICY_REF(lb_policy, "config_change");
GRPC_ERROR_UNREF(state_error);
state =
grpc_lb_policy_check_connectivity(exec_ctx, lb_policy, &state_error);
}
grpc_resolver_result_unref(exec_ctx, chand->resolver_result);
}
chand->resolver_result = NULL;
if (lb_policy != NULL) {
grpc_pollset_set_add_pollset_set(exec_ctx, lb_policy->interested_parties,
chand->interested_parties);
}
gpr_mu_lock(&chand->mu);
old_lb_policy = chand->lb_policy;
chand->lb_policy = lb_policy;
if (lb_policy != NULL) {
grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
NULL);
} else if (chand->resolver == NULL /* disconnected */) {
grpc_closure_list_fail_all(
&chand->waiting_for_config_closures,
GRPC_ERROR_CREATE_REFERENCING("Channel disconnected", &error, 1));
grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
NULL);
}
if (lb_policy != NULL && chand->exit_idle_when_lb_policy_arrives) {
GRPC_LB_POLICY_REF(lb_policy, "exit_idle");
exit_idle = true;
chand->exit_idle_when_lb_policy_arrives = false;
}
if (error == GRPC_ERROR_NONE && chand->resolver) {
set_channel_connectivity_state_locked(
exec_ctx, chand, state, GRPC_ERROR_REF(state_error), "new_lb+resolver");
if (lb_policy != NULL) {
watch_lb_policy(exec_ctx, chand, lb_policy, state);
}
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver, &chand->resolver_result,
&chand->on_resolver_result_changed);
gpr_mu_unlock(&chand->mu);
} else {
if (chand->resolver != NULL) {
grpc_resolver_shutdown(exec_ctx, chand->resolver);
GRPC_RESOLVER_UNREF(exec_ctx, chand->resolver, "channel");
chand->resolver = NULL;
}
grpc_error *refs[] = {error, state_error};
set_channel_connectivity_state_locked(
exec_ctx, chand, GRPC_CHANNEL_SHUTDOWN,
GRPC_ERROR_CREATE_REFERENCING("Got config after disconnection", refs,
GPR_ARRAY_SIZE(refs)),
"resolver_gone");
gpr_mu_unlock(&chand->mu);
}
if (exit_idle) {
grpc_lb_policy_exit_idle(exec_ctx, lb_policy);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "exit_idle");
}
if (old_lb_policy != NULL) {
grpc_pollset_set_del_pollset_set(
exec_ctx, old_lb_policy->interested_parties, chand->interested_parties);
GRPC_LB_POLICY_UNREF(exec_ctx, old_lb_policy, "channel");
}
if (lb_policy != NULL) {
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "config_change");
}
GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "resolver");
GRPC_ERROR_UNREF(state_error);
}
static void cc_on_config_changed(grpc_exec_ctx *exec_ctx, void *arg,
bool iomgr_success) {
channel_data *chand = arg;
grpc_lb_policy *lb_policy = NULL;
grpc_lb_policy *old_lb_policy;
grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
int exit_idle = 0;
if (chand->incoming_configuration != NULL) {
lb_policy = grpc_client_config_get_lb_policy(chand->incoming_configuration);
if (lb_policy != NULL) {
GRPC_LB_POLICY_REF(lb_policy, "channel");
GRPC_LB_POLICY_REF(lb_policy, "config_change");
state = grpc_lb_policy_check_connectivity(exec_ctx, lb_policy);
}
grpc_client_config_unref(exec_ctx, chand->incoming_configuration);
}
chand->incoming_configuration = NULL;
if (lb_policy != NULL) {
grpc_pollset_set_add_pollset_set(exec_ctx, lb_policy->interested_parties,
chand->interested_parties);
}
gpr_mu_lock(&chand->mu_config);
old_lb_policy = chand->lb_policy;
chand->lb_policy = lb_policy;
if (lb_policy != NULL || chand->resolver == NULL /* disconnected */) {
grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
NULL);
}
if (lb_policy != NULL && chand->exit_idle_when_lb_policy_arrives) {
GRPC_LB_POLICY_REF(lb_policy, "exit_idle");
exit_idle = 1;
chand->exit_idle_when_lb_policy_arrives = 0;
}
if (iomgr_success && chand->resolver) {
set_channel_connectivity_state_locked(exec_ctx, chand, state,
"new_lb+resolver");
if (lb_policy != NULL) {
watch_lb_policy(exec_ctx, chand, lb_policy, state);
}
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver,
&chand->incoming_configuration,
&chand->on_config_changed);
gpr_mu_unlock(&chand->mu_config);
} else {
if (chand->resolver != NULL) {
grpc_resolver_shutdown(exec_ctx, chand->resolver);
GRPC_RESOLVER_UNREF(exec_ctx, chand->resolver, "channel");
chand->resolver = NULL;
}
set_channel_connectivity_state_locked(
exec_ctx, chand, GRPC_CHANNEL_FATAL_FAILURE, "resolver_gone");
gpr_mu_unlock(&chand->mu_config);
}
if (exit_idle) {
grpc_lb_policy_exit_idle(exec_ctx, lb_policy);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "exit_idle");
}
if (old_lb_policy != NULL) {
grpc_pollset_set_del_pollset_set(
exec_ctx, old_lb_policy->interested_parties, chand->interested_parties);
GRPC_LB_POLICY_UNREF(exec_ctx, old_lb_policy, "channel");
}
if (lb_policy != NULL) {
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "config_change");
}
GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "resolver");
}
/* Same FD added multiple times to the pollset_set tree */
void pollset_set_test_dup_fds() {
/* We construct the following structure for this test:
*
* +---> FD0
* |
* |
* PSS0---+
* | +---> FD0 (also under PSS0)
* | |
* +---> PSS1--+ +--> FD1 (also under PSS1)
* | |
* +---> PS ---+
* | |
* | +--> FD2
* +---> FD1
*/
grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
grpc_pollset_worker *worker;
gpr_timespec deadline;
test_fd tfds[3];
test_pollset pollset;
test_pollset_set pollset_sets[2];
const int num_fds = GPR_ARRAY_SIZE(tfds);
const int num_ps = 1;
const int num_pss = GPR_ARRAY_SIZE(pollset_sets);
init_test_fds(&exec_ctx, tfds, num_fds);
init_test_pollsets(&pollset, num_ps);
init_test_pollset_sets(pollset_sets, num_pss);
/* Construct the structure */
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[0].pss, tfds[0].fd);
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[1].pss, tfds[0].fd);
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[1].pss, tfds[1].fd);
grpc_pollset_add_fd(&exec_ctx, pollset.ps, tfds[1].fd);
grpc_pollset_add_fd(&exec_ctx, pollset.ps, tfds[2].fd);
grpc_pollset_set_add_pollset(&exec_ctx, pollset_sets[1].pss, pollset.ps);
grpc_pollset_set_add_pollset_set(&exec_ctx, pollset_sets[0].pss,
pollset_sets[1].pss);
/* Test. Make all FDs readable and make sure that can be observed by doing a
* grpc_pollset_work on the pollset 'PS' */
make_test_fds_readable(tfds, num_fds);
gpr_mu_lock(pollset.mu);
deadline = grpc_timeout_milliseconds_to_deadline(2);
GPR_ASSERT(GRPC_ERROR_NONE ==
grpc_pollset_work(&exec_ctx, pollset.ps, &worker,
gpr_now(GPR_CLOCK_MONOTONIC), deadline));
gpr_mu_unlock(pollset.mu);
grpc_exec_ctx_flush(&exec_ctx);
verify_readable_and_reset(&exec_ctx, tfds, num_fds);
grpc_exec_ctx_flush(&exec_ctx);
/* Tear down */
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[0].pss, tfds[0].fd);
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[1].pss, tfds[0].fd);
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[1].pss, tfds[1].fd);
grpc_pollset_set_del_pollset(&exec_ctx, pollset_sets[1].pss, pollset.ps);
grpc_pollset_set_del_pollset_set(&exec_ctx, pollset_sets[0].pss,
pollset_sets[1].pss);
grpc_exec_ctx_flush(&exec_ctx);
cleanup_test_fds(&exec_ctx, tfds, num_fds);
cleanup_test_pollsets(&exec_ctx, &pollset, num_ps);
cleanup_test_pollset_sets(&exec_ctx, pollset_sets, num_pss);
grpc_exec_ctx_finish(&exec_ctx);
}
/* Test some typical scenarios in pollset_set */
static void pollset_set_test_basic() {
/* We construct the following structure for this test:
*
* +---> FD0 (Added before PSS1, PS1 and PS2 are added to PSS0)
* |
* +---> FD5 (Added after PSS1, PS1 and PS2 are added to PSS0)
* |
* |
* | +---> FD1 (Added before PSS1 is added to PSS0)
* | |
* | +---> FD6 (Added after PSS1 is added to PSS0)
* | |
* +---> PSS1--+ +--> FD2 (Added before PS0 is added to PSS1)
* | | |
* | +---> PS0---+
* | |
* PSS0---+ +--> FD7 (Added after PS0 is added to PSS1)
* |
* |
* | +---> FD3 (Added before PS1 is added to PSS0)
* | |
* +---> PS1---+
* | |
* | +---> FD8 (Added after PS1 added to PSS0)
* |
* |
* | +---> FD4 (Added before PS2 is added to PSS0)
* | |
* +---> PS2---+
* |
* +---> FD9 (Added after PS2 is added to PSS0)
*/
grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
grpc_pollset_worker *worker;
gpr_timespec deadline;
test_fd tfds[10];
test_pollset pollsets[3];
test_pollset_set pollset_sets[2];
const int num_fds = GPR_ARRAY_SIZE(tfds);
const int num_ps = GPR_ARRAY_SIZE(pollsets);
const int num_pss = GPR_ARRAY_SIZE(pollset_sets);
init_test_fds(&exec_ctx, tfds, num_fds);
init_test_pollsets(pollsets, num_ps);
init_test_pollset_sets(pollset_sets, num_pss);
/* Construct the pollset_set/pollset/fd tree (see diagram above) */
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[0].pss, tfds[0].fd);
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[1].pss, tfds[1].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[0].ps, tfds[2].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[1].ps, tfds[3].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[2].ps, tfds[4].fd);
grpc_pollset_set_add_pollset_set(&exec_ctx, pollset_sets[0].pss,
pollset_sets[1].pss);
grpc_pollset_set_add_pollset(&exec_ctx, pollset_sets[1].pss, pollsets[0].ps);
grpc_pollset_set_add_pollset(&exec_ctx, pollset_sets[0].pss, pollsets[1].ps);
grpc_pollset_set_add_pollset(&exec_ctx, pollset_sets[0].pss, pollsets[2].ps);
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[0].pss, tfds[5].fd);
grpc_pollset_set_add_fd(&exec_ctx, pollset_sets[1].pss, tfds[6].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[0].ps, tfds[7].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[1].ps, tfds[8].fd);
grpc_pollset_add_fd(&exec_ctx, pollsets[2].ps, tfds[9].fd);
grpc_exec_ctx_flush(&exec_ctx);
/* Test that if any FD in the above structure is readable, it is observable by
* doing grpc_pollset_work on any pollset
*
* For every pollset, do the following:
* - (Ensure that all FDs are in reset state)
* - Make all FDs readable
* - Call grpc_pollset_work() on the pollset
* - Flush the exec_ctx
* - Verify that on_readable call back was called for all FDs (and
* reset the FDs)
* */
for (int i = 0; i < num_ps; i++) {
make_test_fds_readable(tfds, num_fds);
gpr_mu_lock(pollsets[i].mu);
deadline = grpc_timeout_milliseconds_to_deadline(2);
GPR_ASSERT(GRPC_ERROR_NONE ==
grpc_pollset_work(&exec_ctx, pollsets[i].ps, &worker,
gpr_now(GPR_CLOCK_MONOTONIC), deadline));
gpr_mu_unlock(pollsets[i].mu);
grpc_exec_ctx_flush(&exec_ctx);
verify_readable_and_reset(&exec_ctx, tfds, num_fds);
grpc_exec_ctx_flush(&exec_ctx);
}
/* Test tear down */
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[0].pss, tfds[0].fd);
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[0].pss, tfds[5].fd);
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[1].pss, tfds[1].fd);
grpc_pollset_set_del_fd(&exec_ctx, pollset_sets[1].pss, tfds[6].fd);
grpc_exec_ctx_flush(&exec_ctx);
grpc_pollset_set_del_pollset(&exec_ctx, pollset_sets[1].pss, pollsets[0].ps);
grpc_pollset_set_del_pollset(&exec_ctx, pollset_sets[0].pss, pollsets[1].ps);
grpc_pollset_set_del_pollset(&exec_ctx, pollset_sets[0].pss, pollsets[2].ps);
grpc_pollset_set_del_pollset_set(&exec_ctx, pollset_sets[0].pss,
pollset_sets[1].pss);
grpc_exec_ctx_flush(&exec_ctx);
cleanup_test_fds(&exec_ctx, tfds, num_fds);
cleanup_test_pollsets(&exec_ctx, pollsets, num_ps);
cleanup_test_pollset_sets(&exec_ctx, pollset_sets, num_pss);
grpc_exec_ctx_finish(&exec_ctx);
}
