Module safe_drive::selector

Selector provides functions like select or epoll. This is used to single threaded execution. For multi threaded execution, this is used internally.

Example

use safe_drive::{
    context::Context, logger::Logger, msg::common_interfaces::std_msgs, pr_info,
};
use std::time::Duration;

// First of all, you need create a context.
let ctx = Context::new().unwrap();

// Create a subscribe node.
let node_sub = ctx
    .create_node("selector_rs", None, Default::default())
    .unwrap();

// Create a subscriber.
let subscriber = node_sub
    .create_subscriber::<std_msgs::msg::String>("selector_topic", None,
).unwrap();

// Create a selector, which is for IO multiplexing.
let mut selector = ctx.create_selector().unwrap();

// Create a logger.
let logger_sub = Logger::new("selector_rs");

// Add subscriber to the selector.
// The 2nd argument is a callback function.
// If data arrive, the callback will be invoked.
selector.add_subscriber(
    subscriber,
    Box::new(move |msg| {
        // Print the message
        pr_info!(logger_sub, "Received: msg = {}", msg.data); // Print a message.
    }),
);

// Create a wall timer, which invoke the callback periodically.
selector.add_wall_timer(
    "timer_name", // name of the timer
    Duration::from_millis(100),
    Box::new(move || ()),
);

// Spin.
for _ in 0..10 {
    selector.wait().unwrap();
}

Structs

• Selector
  Selector invokes callback functions associated with subscribers, services, timers, or condition variables. Selector cannot send to another thread and shared by multiple threads. So, use this for single threaded execution.