void grpc_client_channel_set_transport_setup(grpc_channel_stack *channel_stack,
grpc_transport_setup *setup) {
/* post construction initialization: set the transport setup pointer */
grpc_channel_element *elem = grpc_channel_stack_last_element(channel_stack);
channel_data *chand = elem->channel_data;
GPR_ASSERT(!chand->transport_setup);
chand->transport_setup = setup;
}
void grpc_client_uchannel_set_connected_subchannel(
grpc_channel *uchannel, grpc_connected_subchannel *connected_subchannel) {
grpc_channel_element *elem =
grpc_channel_stack_last_element(grpc_channel_get_channel_stack(uchannel));
channel_data *chand = elem->channel_data;
GPR_ASSERT(elem->filter == &grpc_client_uchannel_filter);
gpr_mu_lock(&chand->mu_state);
chand->connected_subchannel = connected_subchannel;
GRPC_CONNECTED_SUBCHANNEL_REF(connected_subchannel, "uchannel");
gpr_mu_unlock(&chand->mu_state);
}
static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
bool due_to_completion, grpc_error *error) {
if (due_to_completion) {
grpc_timer_cancel(exec_ctx, &w->alarm);
} else {
grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
grpc_channel_get_channel_stack(w->channel));
grpc_client_channel_watch_connectivity_state(
exec_ctx, client_channel_elem,
grpc_polling_entity_create_from_pollset(grpc_cq_pollset(w->cq)), NULL,
&w->on_complete, NULL);
}
gpr_mu_lock(&w->mu);
if (due_to_completion) {
if (GRPC_TRACER_ON(grpc_trace_operation_failures)) {
GRPC_LOG_IF_ERROR("watch_completion_error", GRPC_ERROR_REF(error));
}
GRPC_ERROR_UNREF(error);
error = GRPC_ERROR_NONE;
} else {
if (error == GRPC_ERROR_NONE) {
error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
"Timed out waiting for connection state change");
} else if (error == GRPC_ERROR_CANCELLED) {
error = GRPC_ERROR_NONE;
}
}
switch (w->phase) {
case WAITING:
GRPC_ERROR_REF(error);
w->error = error;
w->phase = READY_TO_CALL_BACK;
break;
case READY_TO_CALL_BACK:
if (error != GRPC_ERROR_NONE) {
GPR_ASSERT(!due_to_completion);
GRPC_ERROR_UNREF(w->error);
GRPC_ERROR_REF(error);
w->error = error;
}
w->phase = CALLING_BACK_AND_FINISHED;
grpc_cq_end_op(exec_ctx, w->cq, w->tag, w->error, finished_completion, w,
&w->completion_storage);
break;
case CALLING_BACK_AND_FINISHED:
GPR_UNREACHABLE_CODE(return );
break;
}
gpr_mu_unlock(&w->mu);
GRPC_ERROR_UNREF(error);
}
static void delete_state_watcher(grpc_exec_ctx *exec_ctx, state_watcher *w) {
grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
grpc_channel_get_channel_stack(w->channel));
if (client_channel_elem->filter == &grpc_client_channel_filter) {
GRPC_CHANNEL_INTERNAL_UNREF(exec_ctx, w->channel,
"watch_channel_connectivity");
} else {
abort();
}
gpr_mu_destroy(&w->mu);
gpr_free(w);
}
static void assert_channel_connectivity(
grpc_channel *ch, size_t num_accepted_conn_states,
grpc_connectivity_state accepted_conn_state, ...) {
size_t i;
grpc_channel_stack *client_stack;
grpc_channel_element *client_channel_filter;
grpc_connectivity_state actual_conn_state;
grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
va_list ap;
client_stack = grpc_channel_get_channel_stack(ch);
client_channel_filter = grpc_channel_stack_last_element(client_stack);
actual_conn_state = grpc_client_channel_check_connectivity_state(
&exec_ctx, client_channel_filter, 0 /* don't try to connect */);
grpc_exec_ctx_finish(&exec_ctx);
va_start(ap, accepted_conn_state);
for (i = 0; i < num_accepted_conn_states; i++) {
if (actual_conn_state == accepted_conn_state) {
break;
}
accepted_conn_state = va_arg(ap, grpc_connectivity_state);
}
va_end(ap);
if (i == num_accepted_conn_states) {
char **accepted_strs =
gpr_malloc(sizeof(char *) * num_accepted_conn_states);
char *accepted_str_joined;
va_start(ap, accepted_conn_state);
for (i = 0; i < num_accepted_conn_states; i++) {
GPR_ASSERT(gpr_asprintf(&accepted_strs[i], "%d", accepted_conn_state) >
0);
accepted_conn_state = va_arg(ap, grpc_connectivity_state);
}
va_end(ap);
accepted_str_joined = gpr_strjoin_sep((const char **)accepted_strs,
num_accepted_conn_states, ", ", NULL);
gpr_log(
GPR_ERROR,
"Channel connectivity assertion failed: expected <one of [%s]>, got %d",
accepted_str_joined, actual_conn_state);
for (i = 0; i < num_accepted_conn_states; i++) {
gpr_free(accepted_strs[i]);
}
gpr_free(accepted_strs);
gpr_free(accepted_str_joined);
abort();
}
}
void grpc_channel_watch_connectivity_state(
grpc_channel *channel, grpc_connectivity_state last_observed_state,
gpr_timespec deadline, grpc_completion_queue *cq, void *tag) {
grpc_channel_element *client_channel_elem =
grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
state_watcher *w = (state_watcher *)gpr_malloc(sizeof(*w));
GRPC_API_TRACE(
"grpc_channel_watch_connectivity_state("
"channel=%p, last_observed_state=%d, "
"deadline=gpr_timespec { tv_sec: %" PRId64
", tv_nsec: %d, clock_type: %d }, "
"cq=%p, tag=%p)",
7, (channel, (int)last_observed_state, deadline.tv_sec, deadline.tv_nsec,
(int)deadline.clock_type, cq, tag));
GPR_ASSERT(grpc_cq_begin_op(cq, tag));
gpr_mu_init(&w->mu);
GRPC_CLOSURE_INIT(&w->on_complete, watch_complete, w,
grpc_schedule_on_exec_ctx);
GRPC_CLOSURE_INIT(&w->on_timeout, timeout_complete, w,
grpc_schedule_on_exec_ctx);
w->phase = WAITING;
w->state = last_observed_state;
w->cq = cq;
w->tag = tag;
w->channel = channel;
w->error = NULL;
watcher_timer_init_arg *wa =
(watcher_timer_init_arg *)gpr_malloc(sizeof(watcher_timer_init_arg));
wa->w = w;
wa->deadline = deadline;
GRPC_CLOSURE_INIT(&w->watcher_timer_init, watcher_timer_init, wa,
grpc_schedule_on_exec_ctx);
if (client_channel_elem->filter == &grpc_client_channel_filter) {
GRPC_CHANNEL_INTERNAL_REF(channel, "watch_channel_connectivity");
grpc_client_channel_watch_connectivity_state(
&exec_ctx, client_channel_elem,
grpc_polling_entity_create_from_pollset(grpc_cq_pollset(cq)), &w->state,
&w->on_complete, &w->watcher_timer_init);
} else {
abort();
}
grpc_exec_ctx_finish(&exec_ctx);
}
void grpc_connected_channel_bind_transport(grpc_channel_stack *channel_stack,
grpc_transport *transport) {
/* Assumes that the connected channel filter is always the last filter
in a channel stack */
grpc_channel_element *elem = grpc_channel_stack_last_element(channel_stack);
channel_data *cd = (channel_data *)elem->channel_data;
GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
GPR_ASSERT(cd->transport == NULL);
cd->transport = transport;
/* HACK(ctiller): increase call stack size for the channel to make space
for channel data. We need a cleaner (but performant) way to do this,
and I'm not sure what that is yet.
This is only "safe" because call stacks place no additional data after
the last call element, and the last call element MUST be the connected
channel. */
channel_stack->call_stack_size += grpc_transport_stream_size(transport);
}
void grpc_client_channel_set_resolver(grpc_exec_ctx *exec_ctx,
grpc_channel_stack *channel_stack,
grpc_resolver *resolver) {
/* post construction initialization: set the transport setup pointer */
grpc_channel_element *elem = grpc_channel_stack_last_element(channel_stack);
channel_data *chand = elem->channel_data;
gpr_mu_lock(&chand->mu);
GPR_ASSERT(!chand->resolver);
chand->resolver = resolver;
GRPC_RESOLVER_REF(resolver, "channel");
if (!grpc_closure_list_empty(chand->waiting_for_config_closures) ||
chand->exit_idle_when_lb_policy_arrives) {
chand->started_resolving = true;
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, resolver, &chand->resolver_result,
&chand->on_resolver_result_changed);
}
gpr_mu_unlock(&chand->mu);
}
grpc_connectivity_state grpc_channel_check_connectivity_state(
grpc_channel *channel, int try_to_connect) {
/* forward through to the underlying client channel */
grpc_channel_element *client_channel_elem =
grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
grpc_connectivity_state state;
GRPC_API_TRACE(
"grpc_channel_check_connectivity_state(channel=%p, try_to_connect=%d)", 2,
(channel, try_to_connect));
if (client_channel_elem->filter == &grpc_client_channel_filter) {
state = grpc_client_channel_check_connectivity_state(
&exec_ctx, client_channel_elem, try_to_connect);
grpc_exec_ctx_finish(&exec_ctx);
return state;
}
gpr_log(GPR_ERROR,
"grpc_channel_check_connectivity_state called on something that is "
"not a client channel, but '%s'",
client_channel_elem->filter->name);
grpc_exec_ctx_finish(&exec_ctx);
return GRPC_CHANNEL_SHUTDOWN;
}
grpc_transport_setup_result grpc_client_channel_transport_setup_complete(
grpc_channel_stack *channel_stack, grpc_transport *transport,
grpc_channel_filter const **channel_filters, size_t num_channel_filters,
grpc_mdctx *mdctx) {
/* we just got a new transport: lets create a child channel stack for it */
grpc_channel_element *elem = grpc_channel_stack_last_element(channel_stack);
channel_data *chand = elem->channel_data;
size_t num_child_filters = 2 + num_channel_filters;
grpc_channel_filter const **child_filters;
grpc_transport_setup_result result;
grpc_child_channel *old_active = NULL;
call_data **waiting_children;
size_t waiting_child_count;
size_t i;
grpc_call_op *call_ops;
/* build the child filter stack */
child_filters = gpr_malloc(sizeof(grpc_channel_filter *) * num_child_filters);
/* we always need a link back filter to get back to the connected channel */
child_filters[0] = &grpc_child_channel_top_filter;
for (i = 0; i < num_channel_filters; i++) {
child_filters[i + 1] = channel_filters[i];
}
/* and we always need a connected channel to talk to the transport */
child_filters[num_child_filters - 1] = &grpc_connected_channel_filter;
GPR_ASSERT(elem->filter == &grpc_client_channel_filter);
/* BEGIN LOCKING CHANNEL */
gpr_mu_lock(&chand->mu);
chand->transport_setup_initiated = 0;
if (chand->active_child) {
old_active = chand->active_child;
}
chand->active_child = grpc_child_channel_create(
elem, child_filters, num_child_filters, chand->args, mdctx);
result =
grpc_connected_channel_bind_transport(chand->active_child, transport);
/* capture the waiting children - we'll activate them outside the lock
to avoid re-entrancy problems */
waiting_children = chand->waiting_children;
waiting_child_count = chand->waiting_child_count;
/* bumping up inflight_requests here avoids taking a lock per rpc below */
chand->waiting_children = NULL;
chand->waiting_child_count = 0;
chand->waiting_child_capacity = 0;
call_ops = gpr_malloc(sizeof(grpc_call_op) * waiting_child_count);
for (i = 0; i < waiting_child_count; i++) {
call_ops[i].type = GRPC_SEND_START;
call_ops[i].dir = GRPC_CALL_DOWN;
call_ops[i].flags = waiting_children[i]->s.waiting.start_flags;
call_ops[i].done_cb = waiting_children[i]->s.waiting.on_complete;
call_ops[i].user_data =
waiting_children[i]->s.waiting.on_complete_user_data;
call_ops[i].data.start.pollset = waiting_children[i]->s.waiting.pollset;
if (!prepare_activate(waiting_children[i]->elem, chand->active_child)) {
waiting_children[i] = NULL;
call_ops[i].done_cb(call_ops[i].user_data, GRPC_OP_ERROR);
}
}
/* END LOCKING CHANNEL */
gpr_mu_unlock(&chand->mu);
/* activate any pending operations - this is safe to do as we guarantee one
and only one write operation per request at the surface api - if we lose
that guarantee we need to do some curly locking here */
for (i = 0; i < waiting_child_count; i++) {
if (waiting_children[i]) {
complete_activate(waiting_children[i]->elem, &call_ops[i]);
}
}
gpr_free(waiting_children);
gpr_free(call_ops);
gpr_free(child_filters);
if (old_active) {
grpc_child_channel_destroy(old_active, 1);
}
return result;
}
int grpc_channel_support_connectivity_watcher(grpc_channel *channel) {
grpc_channel_element *client_channel_elem =
grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
return client_channel_elem->filter != &grpc_client_channel_filter ? 0 : 1;
}
int grpc_channel_num_external_connectivity_watchers(grpc_channel *channel) {
grpc_channel_element *client_channel_elem =
grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
return grpc_client_channel_num_external_connectivity_watchers(
client_channel_elem);
}
