bool
wait_for_client_to_be_ready(
rcl_client_t * client,
size_t max_tries,
int64_t period_ms)
{
rcl_wait_set_t wait_set = rcl_get_zero_initialized_wait_set();
rcl_ret_t ret = rcl_wait_set_init(&wait_set, 0, 0, 0, 1, 0, rcl_get_default_allocator());
if (ret != RCL_RET_OK) {
fprintf(stderr, "Error in wait set init: %s\n", rcl_get_error_string_safe());
return false;
}
auto wait_set_exit = make_scope_exit([&wait_set]() {
if (rcl_wait_set_fini(&wait_set) != RCL_RET_OK) {
fprintf(stderr, "Error in wait set fini: %s\n", rcl_get_error_string_safe());
throw std::runtime_error("error while waiting for client");
}
});
size_t iteration = 0;
do {
++iteration;
if (rcl_wait_set_clear_clients(&wait_set) != RCL_RET_OK) {
fprintf(stderr, "Error in wait_set_clear_clients: %s\n", rcl_get_error_string_safe());
return false;
}
if (rcl_wait_set_add_client(&wait_set, client) != RCL_RET_OK) {
fprintf(stderr, "Error in wait_set_add_client: %s\n", rcl_get_error_string_safe());
return false;
}
ret = rcl_wait(&wait_set, RCL_MS_TO_NS(period_ms));
if (ret == RCL_RET_TIMEOUT) {
continue;
}
if (ret != RCL_RET_OK) {
fprintf(stderr, "Error in wait: %s\n", rcl_get_error_string_safe());
return false;
}
for (size_t i = 0; i < wait_set.size_of_clients; ++i) {
if (wait_set.clients[i] && wait_set.clients[i] == client) {
return true;
}
}
} while (iteration < max_tries);
return false;
}
void
wait_for_service_to_be_ready(
rcl_service_t * service,
size_t max_tries,
int64_t period_ms,
bool & success)
{
rcl_wait_set_t wait_set = rcl_get_zero_initialized_wait_set();
rcl_ret_t ret = rcl_wait_set_init(&wait_set, 0, 0, 0, 0, 1, rcl_get_default_allocator());
ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
auto wait_set_exit = make_scope_exit([&wait_set]() {
stop_memory_checking();
rcl_ret_t ret = rcl_wait_set_fini(&wait_set);
ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
});
size_t iteration = 0;
do {
++iteration;
ret = rcl_wait_set_clear_services(&wait_set);
ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
ret = rcl_wait_set_add_service(&wait_set, service);
ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
ret = rcl_wait(&wait_set, RCL_MS_TO_NS(period_ms));
if (ret == RCL_RET_TIMEOUT) {
continue;
}
ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
for (size_t i = 0; i < wait_set.size_of_services; ++i) {
if (wait_set.services[i] && wait_set.services[i] == service) {
success = true;
return;
}
}
} while (iteration < max_tries);
success = false;
}
void
GraphListener::run_loop()
{
while (true) {
// If shutdown() was called, exit.
if (is_shutdown_.load()) {
return;
}
rcl_ret_t ret;
{
// This "barrier" lock ensures that other functions can acquire the
// node_graph_interfaces_mutex_ after waking up rcl_wait.
std::lock_guard<std::mutex> nodes_barrier_lock(node_graph_interfaces_barrier_mutex_);
// This is ownership is passed to nodes_lock in the next line.
node_graph_interfaces_mutex_.lock();
}
// This lock is released when the loop continues or exits.
std::lock_guard<std::mutex> nodes_lock(node_graph_interfaces_mutex_, std::adopt_lock);
// Resize the wait set if necessary.
if (wait_set_.size_of_guard_conditions < (node_graph_interfaces_.size() + 2)) {
ret = rcl_wait_set_resize_guard_conditions(&wait_set_, node_graph_interfaces_.size() + 2);
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to resize wait set");
}
}
// Clear the wait set's guard conditions.
ret = rcl_wait_set_clear_guard_conditions(&wait_set_);
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to clear wait set");
}
// Put the interrupt guard condition in the wait set.
ret = rcl_wait_set_add_guard_condition(&wait_set_, &interrupt_guard_condition_);
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to add interrupt guard condition to wait set");
}
// Put the shutdown guard condition in the wait set.
ret = rcl_wait_set_add_guard_condition(&wait_set_, shutdown_guard_condition_);
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to add shutdown guard condition to wait set");
}
// Put graph guard conditions for each node into the wait set.
for (const auto node_ptr : node_graph_interfaces_) {
// Only wait on graph changes if some user of the node is watching.
if (node_ptr->count_graph_users() == 0) {
continue;
}
// Add the graph guard condition for the node to the wait set.
auto graph_gc = node_ptr->get_graph_guard_condition();
if (!graph_gc) {
throw_from_rcl_error(RCL_RET_ERROR, "failed to get graph guard condition");
}
ret = rcl_wait_set_add_guard_condition(&wait_set_, graph_gc);
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to add graph guard condition to wait set");
}
}
// Wait for: graph changes, interrupt, or shutdown/SIGINT
ret = rcl_wait(&wait_set_, -1); // block for ever until a guard condition is triggered
if (RCL_RET_TIMEOUT == ret) {
throw std::runtime_error("rcl_wait unexpectedly timed out");
}
if (RCL_RET_OK != ret) {
throw_from_rcl_error(ret, "failed to wait on wait set");
}
bool shutdown_guard_condition_triggered = false;
// Check to see if the shutdown guard condition has been triggered.
for (size_t i = 0; i < wait_set_.size_of_guard_conditions; ++i) {
if (shutdown_guard_condition_ == wait_set_.guard_conditions[i]) {
shutdown_guard_condition_triggered = true;
}
}
// Notify nodes who's guard conditions are set (triggered).
for (const auto node_ptr : node_graph_interfaces_) {
auto graph_gc = node_ptr->get_graph_guard_condition();
if (!graph_gc) {
throw_from_rcl_error(RCL_RET_ERROR, "failed to get graph guard condition");
}
for (size_t i = 0; i < wait_set_.size_of_guard_conditions; ++i) {
if (graph_gc == wait_set_.guard_conditions[i]) {
node_ptr->notify_graph_change();
}
}
if (shutdown_guard_condition_triggered) {
// If shutdown, then notify the node of this as well.
node_ptr->notify_shutdown();
}
}
} // while (true)
}