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pub mod errors;
pub mod reader;
pub mod ring;
pub mod writer;
use errors::BondiError;
use reader::Reader;
use ring::Ring;
use anyhow::Result;
use writer::Writer;
use std::{cell::Cell, sync::Arc};
pub struct Bondi<T> {
ring: Arc<Ring<T>>,
writer_created: Cell<bool>,
}
impl<T: Clone + std::fmt::Debug> Bondi<T> {
pub fn new(capacity: usize) -> Self {
Self {
ring: Arc::new(Ring::new(capacity)),
writer_created: Cell::new(false),
}
}
pub fn get_tx(&self) -> Result<Writer<T>> {
if self.writer_created.get() {
return Err(BondiError::WriterAlreadyExists.into());
}
self.writer_created.set(true);
Ok(Writer::new(Arc::clone(&self.ring)))
}
pub fn get_rx(&self) -> Result<Reader<T>> {
let num_consumers = self.ring.new_consumer()?;
Ok(Reader::new(Arc::clone(&self.ring), num_consumers))
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
#[cfg_attr(miri, ignore)]
fn get_many_readers() {
let bondi = Bondi::<usize>::new(100);
let reader = bondi.get_rx().unwrap();
let reader2 = bondi.get_rx().unwrap();
std::thread::spawn(move || {
let _ = reader.read();
});
std::thread::spawn(move || {
let _ = reader2.read();
});
std::thread::sleep(std::time::Duration::from_millis(100));
}
#[test]
fn write_something() {
let bondi = Bondi::<usize>::new(100);
let writer = bondi.get_tx().unwrap();
for i in 0..100 {
writer.write(i);
}
}
#[test]
fn write_and_read_something_one_reader_no_wrap() {
let bondi = Bondi::<usize>::new(100);
let writer = bondi.get_tx().unwrap();
let reader = bondi.get_rx().unwrap();
std::thread::spawn(move || {
for i in 0..100 {
writer.write(i);
}
});
std::thread::spawn(move || {
for i in 0..100 {
assert_eq!(reader.read(), i);
}
})
.join()
.unwrap();
}
#[test]
fn write_and_read_something_two_readers_no_wrap() {
let bondi = Bondi::<usize>::new(100);
let writer = bondi.get_tx().unwrap();
let reader = bondi.get_rx().unwrap();
let reader2 = bondi.get_rx().unwrap();
std::thread::spawn(move || {
for i in 0..100 {
writer.write(i);
assert_eq!(reader.read(), i);
}
});
std::thread::spawn(move || {
for i in 0..100 {
assert_eq!(reader2.read(), i);
}
})
.join()
.unwrap();
}
#[test]
fn write_and_read_something_many_readers_with_wrapping() {
let bondi = Bondi::<usize>::new(100);
let writer = bondi.get_tx().unwrap();
let readers = (0..99).into_iter().map(|_| bondi.get_rx().unwrap());
let last_reader = bondi.get_rx().unwrap();
std::thread::spawn(move || {
for i in 0..200 {
writer.write(i);
}
});
for reader in readers {
std::thread::spawn(move || {
for i in 0..200 {
assert_eq!(reader.read(), i);
}
});
}
std::thread::spawn(move || {
for i in 0..200 {
assert_eq!(last_reader.read(), i);
}
})
.join()
.unwrap();
}
#[test]
#[should_panic(expected = "No reader available")]
fn too_many_readers() {
let max_readers_available = 1000;
let bondi = Bondi::<usize>::new(max_readers_available);
let _readers = (0..max_readers_available)
.into_iter()
.map(|_| bondi.get_rx().unwrap())
.collect::<Vec<_>>();
}
}