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//! Tests copied from Go and manually rewritten in Rust.
//!
//! Source:
//!
//! Copyright & License:
//! - Copyright (c) 2009 The Go Authors
#![allow(clippy::redundant_clone)]
use std::alloc::{GlobalAlloc, Layout, System};
use std::any::Any;
use std::cell::Cell;
use std::collections::HashMap;
use std::sync::atomic::{AtomicI32, AtomicUsize, Ordering::SeqCst};
use std::sync::{Arc, Condvar, Mutex};
use std::thread;
use std::time::Duration;
use crossbeam_channel::{bounded, never, select, tick, unbounded, Receiver, Select, Sender};
fn ms(ms: u64) -> Duration {
Duration::from_millis(ms)
}
struct Chan<T> {
inner: Arc<Mutex<ChanInner<T>>>,
}
struct ChanInner<T> {
s: Option<Sender<T>>,
r: Option<Receiver<T>>,
// Receiver to use when r is None (Go blocks on receiving from nil)
nil_r: Receiver<T>,
// Sender to use when s is None (Go blocks on sending to nil)
nil_s: Sender<T>,
// Hold this receiver to prevent nil sender channel from disconnection
_nil_sr: Receiver<T>,
}
impl<T> Clone for Chan<T> {
fn clone(&self) -> Chan<T> {
Chan {
inner: self.inner.clone(),
}
}
}
impl<T> Chan<T> {
fn send(&self, msg: T) {
let s = self
.inner
.lock()
.unwrap()
.s
.as_ref()
.expect("sending into closed channel")
.clone();
let _ = s.send(msg);
}
fn try_recv(&self) -> Option<T> {
let r = self.inner.lock().unwrap().r.as_ref().unwrap().clone();
r.try_recv().ok()
}
fn recv(&self) -> Option<T> {
let r = self.inner.lock().unwrap().r.as_ref().unwrap().clone();
r.recv().ok()
}
fn close_s(&self) {
self.inner
.lock()
.unwrap()
.s
.take()
.expect("channel sender already closed");
}
fn close_r(&self) {
self.inner
.lock()
.unwrap()
.r
.take()
.expect("channel receiver already closed");
}
fn has_rx(&self) -> bool {
self.inner.lock().unwrap().r.is_some()
}
fn has_tx(&self) -> bool {
self.inner.lock().unwrap().s.is_some()
}
fn rx(&self) -> Receiver<T> {
let inner = self.inner.lock().unwrap();
match inner.r.as_ref() {
None => inner.nil_r.clone(),
Some(r) => r.clone(),
}
}
fn tx(&self) -> Sender<T> {
let inner = self.inner.lock().unwrap();
match inner.s.as_ref() {
None => inner.nil_s.clone(),
Some(s) => s.clone(),
}
}
}
impl<T> Iterator for Chan<T> {
type Item = T;
fn next(&mut self) -> Option<Self::Item> {
self.recv()
}
}
impl<'a, T> IntoIterator for &'a Chan<T> {
type Item = T;
type IntoIter = Chan<T>;
fn into_iter(self) -> Self::IntoIter {
self.clone()
}
}
fn make<T>(cap: usize) -> Chan<T> {
let (s, r) = bounded(cap);
let (nil_s, _nil_sr) = bounded(0);
Chan {
inner: Arc::new(Mutex::new(ChanInner {
s: Some(s),
r: Some(r),
nil_r: never(),
nil_s,
_nil_sr,
})),
}
}
fn make_unbounded<T>() -> Chan<T> {
let (s, r) = unbounded();
let (nil_s, _nil_sr) = bounded(0);
Chan {
inner: Arc::new(Mutex::new(ChanInner {
s: Some(s),
r: Some(r),
nil_r: never(),
nil_s,
_nil_sr,
})),
}
}
#[derive(Clone)]
struct WaitGroup(Arc<WaitGroupInner>);
struct WaitGroupInner {
cond: Condvar,
count: Mutex<i32>,
}
impl WaitGroup {
fn new() -> WaitGroup {
WaitGroup(Arc::new(WaitGroupInner {
cond: Condvar::new(),
count: Mutex::new(0),
}))
}
fn add(&self, delta: i32) {
let mut count = self.0.count.lock().unwrap();
*count += delta;
assert!(*count >= 0);
self.0.cond.notify_all();
}
fn done(&self) {
self.add(-1);
}
fn wait(&self) {
let mut count = self.0.count.lock().unwrap();
while *count > 0 {
count = self.0.cond.wait(count).unwrap();
}
}
}
struct Defer<F: FnOnce()> {
f: Option<Box<F>>,
}
impl<F: FnOnce()> Drop for Defer<F> {
fn drop(&mut self) {
let f = self.f.take().unwrap();
let mut f = Some(f);
let mut f = move || f.take().unwrap()();
f();
}
}
struct Counter;
static ALLOCATED: AtomicUsize = AtomicUsize::new(0);
unsafe impl GlobalAlloc for Counter {
unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
let ret = System.alloc(layout);
if !ret.is_null() {
ALLOCATED.fetch_add(layout.size(), SeqCst);
}
ret
}
unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
System.dealloc(ptr, layout);
ALLOCATED.fetch_sub(layout.size(), SeqCst);
}
}
#[global_allocator]
static A: Counter = Counter;
macro_rules! defer {
($body:expr) => {
let _defer = Defer {
f: Some(Box::new(|| $body)),
};
};
}
macro_rules! go {
(@parse $v:ident, $($tail:tt)*) => {{
let $v = $v.clone();
go!(@parse $($tail)*)
}};
(@parse $body:expr) => {
::std::thread::spawn(move || {
let res = ::std::panic::catch_unwind(::std::panic::AssertUnwindSafe(|| {
$body
}));
if res.is_err() {
eprintln!("goroutine panicked: {:?}", res);
::std::process::abort();
}
})
};
(@parse $($tail:tt)*) => {
compile_error!("invalid `go!` syntax")
};
($($tail:tt)*) => {{
go!(@parse $($tail)*)
}};
}
mod doubleselect {
use super::*;
#[cfg(miri)]
const ITERATIONS: i32 = 100;
#[cfg(not(miri))]
const ITERATIONS: i32 = 10_000;
fn sender(n: i32, c1: Chan<i32>, c2: Chan<i32>, c3: Chan<i32>, c4: Chan<i32>) {
defer! { c1.close_s() }
defer! { c2.close_s() }
defer! { c3.close_s() }
defer! { c4.close_s() }
for i in 0..n {
select! {
send(c1.tx(), i) -> _ => {}
send(c2.tx(), i) -> _ => {}
send(c3.tx(), i) -> _ => {}
send(c4.tx(), i) -> _ => {}
}
}
}
fn mux(out: Chan<i32>, inp: Chan<i32>, done: Chan<bool>) {
for v in inp {
out.send(v);
}
done.send(true);
}
fn recver(inp: Chan<i32>) {
let mut seen = HashMap::new();
for v in &inp {
if seen.contains_key(&v) {
panic!("got duplicate value for {}", v);
}
seen.insert(v, true);
}
}
#[test]
fn main() {
let c1 = make::<i32>(0);
let c2 = make::<i32>(0);
let c3 = make::<i32>(0);
let c4 = make::<i32>(0);
let done = make::<bool>(0);
let cmux = make::<i32>(0);
go!(c1, c2, c3, c4, sender(ITERATIONS, c1, c2, c3, c4));
go!(cmux, c1, done, mux(cmux, c1, done));
go!(cmux, c2, done, mux(cmux, c2, done));
go!(cmux, c3, done, mux(cmux, c3, done));
go!(cmux, c4, done, mux(cmux, c4, done));
go!(done, cmux, {
done.recv();
done.recv();
done.recv();
done.recv();
cmux.close_s();
});
recver(cmux);
}
}
mod fifo {
use super::*;
const N: i32 = 10;
#[test]
fn asynch_fifo() {
let ch = make::<i32>(N as usize);
for i in 0..N {
ch.send(i);
}
for i in 0..N {
if ch.recv() != Some(i) {
panic!("bad receive");
}
}
}
fn chain(ch: Chan<i32>, val: i32, inp: Chan<i32>, out: Chan<i32>) {
inp.recv();
if ch.recv() != Some(val) {
panic!("{}", val);
}
out.send(1);
}
#[test]
fn synch_fifo() {
let ch = make::<i32>(0);
let mut inp = make::<i32>(0);
let start = inp.clone();
for i in 0..N {
let out = make::<i32>(0);
go!(ch, i, inp, out, chain(ch, i, inp, out));
inp = out;
}
start.send(0);
for i in 0..N {
ch.send(i);
}
inp.recv();
}
}
mod goroutines {
use super::*;
fn f(left: Chan<i32>, right: Chan<i32>) {
left.send(right.recv().unwrap());
}
#[test]
fn main() {
let n = 100i32;
let leftmost = make::<i32>(0);
let mut right = leftmost.clone();
let mut left = leftmost.clone();
for _ in 0..n {
right = make::<i32>(0);
go!(left, right, f(left, right));
left = right.clone();
}
go!(right, right.send(1));
leftmost.recv().unwrap();
}
}
mod nonblock {
use super::*;
fn i32receiver(c: Chan<i32>, strobe: Chan<bool>) {
if c.recv().unwrap() != 123 {
panic!("i32 value");
}
strobe.send(true);
}
fn i32sender(c: Chan<i32>, strobe: Chan<bool>) {
c.send(234);
strobe.send(true);
}
fn i64receiver(c: Chan<i64>, strobe: Chan<bool>) {
if c.recv().unwrap() != 123456 {
panic!("i64 value");
}
strobe.send(true);
}
fn i64sender(c: Chan<i64>, strobe: Chan<bool>) {
c.send(234567);
strobe.send(true);
}
fn breceiver(c: Chan<bool>, strobe: Chan<bool>) {
if !c.recv().unwrap() {
panic!("b value");
}
strobe.send(true);
}
fn bsender(c: Chan<bool>, strobe: Chan<bool>) {
c.send(true);
strobe.send(true);
}
fn sreceiver(c: Chan<String>, strobe: Chan<bool>) {
if c.recv().unwrap() != "hello" {
panic!("x value");
}
strobe.send(true);
}
fn ssender(c: Chan<String>, strobe: Chan<bool>) {
c.send("hello again".to_string());
strobe.send(true);
}
const MAX_TRIES: usize = 10000; // Up to 100ms per test.
#[test]
fn main() {
let ticker = tick(Duration::new(0, 10_000)); // 10 us
let sleep = || {
ticker.recv().unwrap();
ticker.recv().unwrap();
thread::yield_now();
thread::yield_now();
thread::yield_now();
};
let sync = make::<bool>(0);
for buffer in 0..2 {
let c32 = make::<i32>(buffer);
let c64 = make::<i64>(buffer);
let cb = make::<bool>(buffer);
let cs = make::<String>(buffer);
select! {
recv(c32.rx()) -> _ => panic!("blocked i32sender"),
default => {}
}
select! {
recv(c64.rx()) -> _ => panic!("blocked i64sender"),
default => {}
}
select! {
recv(cb.rx()) -> _ => panic!("blocked bsender"),
default => {}
}
select! {
recv(cs.rx()) -> _ => panic!("blocked ssender"),
default => {}
}
go!(c32, sync, i32receiver(c32, sync));
let mut r#try = 0;
loop {
select! {
send(c32.tx(), 123) -> _ => break,
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("i32receiver buffer={}", buffer);
panic!("fail")
}
sleep();
}
}
}
sync.recv();
go!(c32, sync, i32sender(c32, sync));
if buffer > 0 {
sync.recv();
}
let mut r#try = 0;
loop {
select! {
recv(c32.rx()) -> v => {
if v != Ok(234) {
panic!("i32sender value");
}
break;
}
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("i32sender buffer={}", buffer);
panic!("fail");
}
sleep();
}
}
}
if buffer == 0 {
sync.recv();
}
go!(c64, sync, i64receiver(c64, sync));
let mut r#try = 0;
loop {
select! {
send(c64.tx(), 123456) -> _ => break,
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("i64receiver buffer={}", buffer);
panic!("fail")
}
sleep();
}
}
}
sync.recv();
go!(c64, sync, i64sender(c64, sync));
if buffer > 0 {
sync.recv();
}
let mut r#try = 0;
loop {
select! {
recv(c64.rx()) -> v => {
if v != Ok(234567) {
panic!("i64sender value");
}
break;
}
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("i64sender buffer={}", buffer);
panic!("fail");
}
sleep();
}
}
}
if buffer == 0 {
sync.recv();
}
go!(cb, sync, breceiver(cb, sync));
let mut r#try = 0;
loop {
select! {
send(cb.tx(), true) -> _ => break,
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("breceiver buffer={}", buffer);
panic!("fail")
}
sleep();
}
}
}
sync.recv();
go!(cb, sync, bsender(cb, sync));
if buffer > 0 {
sync.recv();
}
let mut r#try = 0;
loop {
select! {
recv(cb.rx()) -> v => {
if v != Ok(true) {
panic!("bsender value");
}
break;
}
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("bsender buffer={}", buffer);
panic!("fail");
}
sleep();
}
}
}
if buffer == 0 {
sync.recv();
}
go!(cs, sync, sreceiver(cs, sync));
let mut r#try = 0;
loop {
select! {
send(cs.tx(), "hello".to_string()) -> _ => break,
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("sreceiver buffer={}", buffer);
panic!("fail")
}
sleep();
}
}
}
sync.recv();
go!(cs, sync, ssender(cs, sync));
if buffer > 0 {
sync.recv();
}
let mut r#try = 0;
loop {
select! {
recv(cs.rx()) -> v => {
if v != Ok("hello again".to_string()) {
panic!("ssender value");
}
break;
}
default => {
r#try += 1;
if r#try > MAX_TRIES {
println!("ssender buffer={}", buffer);
panic!("fail");
}
sleep();
}
}
}
if buffer == 0 {
sync.recv();
}
}
}
}
mod select {
use super::*;
#[test]
fn main() {
let shift = Cell::new(0);
let counter = Cell::new(0);
let get_value = || {
counter.set(counter.get() + 1);
1 << shift.get()
};
let send = |mut a: Option<&Chan<u32>>, mut b: Option<&Chan<u32>>| {
let mut i = 0;
let never = make::<u32>(0);
loop {
let nil1 = never.tx();
let nil2 = never.tx();
let v1 = get_value();
let v2 = get_value();
select! {
send(a.map(|c| c.tx()).unwrap_or(nil1), v1) -> _ => {
i += 1;
a = None;
}
send(b.map(|c| c.tx()).unwrap_or(nil2), v2) -> _ => {
i += 1;
b = None;
}
default => break,
}
shift.set(shift.get() + 1);
}
i
};
let a = make::<u32>(1);
let b = make::<u32>(1);
assert_eq!(send(Some(&a), Some(&b)), 2);
let av = a.recv().unwrap();
let bv = b.recv().unwrap();
assert_eq!(av | bv, 3);
assert_eq!(send(Some(&a), None), 1);
assert_eq!(counter.get(), 10);
}
}
mod select2 {
use super::*;
#[cfg(miri)]
const N: i32 = 200;
#[cfg(not(miri))]
const N: i32 = 100000;
#[test]
fn main() {
fn sender(c: &Chan<i32>, n: i32) {
for _ in 0..n {
c.send(1);
}
}
fn receiver(c: &Chan<i32>, dummy: &Chan<i32>, n: i32) {
for _ in 0..n {
select! {
recv(c.rx()) -> _ => {}
recv(dummy.rx()) -> _ => {
panic!("dummy");
}
}
}
}
let c = make_unbounded::<i32>();
let dummy = make_unbounded::<i32>();
ALLOCATED.store(0, SeqCst);
go!(c, sender(&c, N));
receiver(&c, &dummy, N);
let alloc = ALLOCATED.load(SeqCst);
go!(c, sender(&c, N));
receiver(&c, &dummy, N);
assert!(
!(ALLOCATED.load(SeqCst) > alloc
&& (ALLOCATED.load(SeqCst) - alloc) > (N as usize + 10000))
)
}
}
mod select3 {
// TODO
}
mod select4 {
use super::*;
#[test]
fn main() {
let c = make::<i32>(1);
let c1 = make::<i32>(0);
c.send(42);
select! {
recv(c1.rx()) -> _ => panic!("BUG"),
recv(c.rx()) -> v => assert_eq!(v, Ok(42)),
}
}
}
mod select6 {
use super::*;
#[test]
fn main() {
let c1 = make::<bool>(0);
let c2 = make::<bool>(0);
let c3 = make::<bool>(0);
go!(c1, c1.recv());
go!(c1, c2, c3, {
select! {
recv(c1.rx()) -> _ => panic!("dummy"),
recv(c2.rx()) -> _ => c3.send(true),
}
c1.recv();
});
go!(c2, c2.send(true));
c3.recv();
c1.send(true);
c1.send(true);
}
}
mod select7 {
use super::*;
fn recv1(c: Chan<i32>) {
c.recv().unwrap();
}
fn recv2(c: Chan<i32>) {
select! {
recv(c.rx()) -> _ => ()
}
}
fn recv3(c: Chan<i32>) {
let c2 = make::<i32>(1);
select! {
recv(c.rx()) -> _ => (),
recv(c2.rx()) -> _ => ()
}
}
fn send1(recv: fn(Chan<i32>)) {
let c = make::<i32>(1);
go!(c, recv(c));
thread::yield_now();
c.send(1);
}
fn send2(recv: fn(Chan<i32>)) {
let c = make::<i32>(1);
go!(c, recv(c));
thread::yield_now();
select! {
send(c.tx(), 1) -> _ => ()
}
}
fn send3(recv: fn(Chan<i32>)) {
let c = make::<i32>(1);
go!(c, recv(c));
thread::yield_now();
let c2 = make::<i32>(1);
select! {
send(c.tx(), 1) -> _ => (),
send(c2.tx(), 1) -> _ => ()
}
}
#[test]
fn main() {
send1(recv1);
send2(recv1);
send3(recv1);
send1(recv2);
send2(recv2);
send3(recv2);
send1(recv3);
send2(recv3);
send3(recv3);
}
}
mod sieve1 {
use super::*;
fn generate(ch: Chan<i32>) {
let mut i = 2;
loop {
ch.send(i);
i += 1;
}
}
fn filter(in_ch: Chan<i32>, out_ch: Chan<i32>, prime: i32) {
for i in in_ch {
if i % prime != 0 {
out_ch.send(i);
}
}
}
fn sieve(primes: Chan<i32>) {
let mut ch = make::<i32>(1);
go!(ch, generate(ch));
loop {
let prime = ch.recv().unwrap();
primes.send(prime);
let ch1 = make::<i32>(1);
go!(ch, ch1, prime, filter(ch, ch1, prime));
ch = ch1;
}
}
#[test]
fn main() {
let primes = make::<i32>(1);
go!(primes, sieve(primes));
let a = [
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
89, 97,
];
#[cfg(miri)]
let a = &a[..10];
for item in a.iter() {
let x = primes.recv().unwrap();
if x != *item {
println!("{} != {}", x, item);
panic!("fail");
}
}
}
}
mod zerosize {
use super::*;
#[test]
fn zero_size_struct() {
struct ZeroSize;
let _ = make::<ZeroSize>(0);
}
#[test]
fn zero_size_array() {
let _ = make::<[u8; 0]>(0);
}
}
mod chan_test {
use super::*;
#[test]
fn test_chan() {
#[cfg(miri)]
const N: i32 = 12;
#[cfg(not(miri))]
const N: i32 = 200;
#[cfg(miri)]
const MESSAGES_COUNT: i32 = 20;
#[cfg(not(miri))]
const MESSAGES_COUNT: i32 = 100;
for cap in 0..N {
{
// Ensure that receive from empty chan blocks.
let c = make::<i32>(cap as usize);
let recv1 = Arc::new(Mutex::new(false));
go!(c, recv1, {
c.recv();
*recv1.lock().unwrap() = true;
});
let recv2 = Arc::new(Mutex::new(false));
go!(c, recv2, {
c.recv();
*recv2.lock().unwrap() = true;
});
thread::sleep(ms(1));
if *recv1.lock().unwrap() || *recv2.lock().unwrap() {
panic!();
}
// Ensure that non-blocking receive does not block.
select! {
recv(c.rx()) -> _ => panic!(),
default => {}
}
select! {
recv(c.rx()) -> _ => panic!(),
default => {}
}
c.send(0);
c.send(0);
}
{
// Ensure that send to full chan blocks.
let c = make::<i32>(cap as usize);
for i in 0..cap {
c.send(i);
}
let sent = Arc::new(Mutex::new(0));
go!(sent, c, {
c.send(0);
*sent.lock().unwrap() = 1;
});
thread::sleep(ms(1));
if *sent.lock().unwrap() != 0 {
panic!();
}
// Ensure that non-blocking send does not block.
select! {
send(c.tx(), 0) -> _ => panic!(),
default => {}
}
c.recv();
}
{
// Ensure that we receive 0 from closed chan.
let c = make::<i32>(cap as usize);
for i in 0..cap {
c.send(i);
}
c.close_s();
for i in 0..cap {
let v = c.recv();
if v != Some(i) {
panic!();
}
}
if c.recv() != None {
panic!();
}
if c.try_recv() != None {
panic!();
}
}
{
// Ensure that close unblocks receive.
let c = make::<i32>(cap as usize);
let done = make::<bool>(0);
go!(c, done, {
let v = c.try_recv();
done.send(v.is_none());
});
thread::sleep(ms(1));
c.close_s();
if !done.recv().unwrap() {
panic!();
}
}
{
// Send many integers,
// ensure that we receive them non-corrupted in FIFO order.
let c = make::<i32>(cap as usize);
go!(c, {
for i in 0..MESSAGES_COUNT {
c.send(i);
}
});
for i in 0..MESSAGES_COUNT {
if c.recv() != Some(i) {
panic!();
}
}
// Same, but using recv2.
go!(c, {
for i in 0..MESSAGES_COUNT {
c.send(i);
}
});
for i in 0..MESSAGES_COUNT {
if c.recv() != Some(i) {
panic!();
}
}
}
}
}
#[test]
fn test_nonblock_recv_race() {
#[cfg(miri)]
const N: usize = 100;
#[cfg(not(miri))]
const N: usize = 1000;
for _ in 0..N {
let c = make::<i32>(1);
c.send(1);
let t = go!(c, {
select! {
recv(c.rx()) -> _ => {}
default => panic!("chan is not ready"),
}
});
c.close_s();
c.recv();
t.join().unwrap();
}
}
#[test]
fn test_nonblock_select_race() {
#[cfg(miri)]
const N: usize = 100;
#[cfg(not(miri))]
const N: usize = 1000;
let done = make::<bool>(1);
for _ in 0..N {
let c1 = make::<i32>(1);
let c2 = make::<i32>(1);
c1.send(1);
go!(c1, c2, done, {
select! {
recv(c1.rx()) -> _ => {}
recv(c2.rx()) -> _ => {}
default => {
done.send(false);
return;
}
}
done.send(true);
});
c2.send(1);
select! {
recv(c1.rx()) -> _ => {}
default => {}
}
if !done.recv().unwrap() {
panic!("no chan is ready");
}
}
}
#[test]
fn test_nonblock_select_race2() {
#[cfg(miri)]
const N: usize = 100;
#[cfg(not(miri))]
const N: usize = 1000;
let done = make::<bool>(1);
for _ in 0..N {
let c1 = make::<i32>(1);
let c2 = make::<i32>(0);
c1.send(1);
go!(c1, c2, done, {
select! {
recv(c1.rx()) -> _ => {}
recv(c2.rx()) -> _ => {}
default => {
done.send(false);
return;
}
}
done.send(true);
});
c2.close_s();
select! {
recv(c1.rx()) -> _ => {}
default => {}
}
if !done.recv().unwrap() {
panic!("no chan is ready");
}
}
}
#[test]
fn test_self_select() {
// Ensure that send/recv on the same chan in select
// does not crash nor deadlock.
#[cfg(miri)]
const N: usize = 100;
#[cfg(not(miri))]
const N: usize = 1000;
for &cap in &[0, 10] {
let wg = WaitGroup::new();
wg.add(2);
let c = make::<i32>(cap);
for p in 0..2 {
let p = p;
go!(wg, p, c, {
defer! { wg.done() }
for i in 0..N {
if p == 0 || i % 2 == 0 {
select! {
send(c.tx(), p) -> _ => {}
recv(c.rx()) -> v => {
if cap == 0 && v.ok() == Some(p) {
panic!("self receive");
}
}
}
} else {
select! {
recv(c.rx()) -> v => {
if cap == 0 && v.ok() == Some(p) {
panic!("self receive");
}
}
send(c.tx(), p) -> _ => {}
}
}
}
});
}
wg.wait();
}
}
#[test]
fn test_select_stress() {
#[cfg(miri)]
const N: usize = 100;
#[cfg(not(miri))]
const N: usize = 10000;
let c = vec![
make::<i32>(0),
make::<i32>(0),
make::<i32>(2),
make::<i32>(3),
];
// There are 4 goroutines that send N values on each of the chans,
// + 4 goroutines that receive N values on each of the chans,
// + 1 goroutine that sends N values on each of the chans in a single select,
// + 1 goroutine that receives N values on each of the chans in a single select.
// All these sends, receives and selects interact chaotically at runtime,
// but we are careful that this whole construct does not deadlock.
let wg = WaitGroup::new();
wg.add(10);
for k in 0..4 {
go!(k, c, wg, {
for _ in 0..N {
c[k].send(0);
}
wg.done();
});
go!(k, c, wg, {
for _ in 0..N {
c[k].recv();
}
wg.done();
});
}
go!(c, wg, {
let mut n = [0; 4];
let mut c1 = c.iter().map(|c| Some(c.rx().clone())).collect::<Vec<_>>();
for _ in 0..4 * N {
let index = {
let mut sel = Select::new();
let mut opers = [!0; 4];
for &i in &[3, 2, 0, 1] {
if let Some(c) = &c1[i] {
opers[i] = sel.recv(c);
}
}
let oper = sel.select();
let mut index = !0;
for i in 0..4 {
if opers[i] == oper.index() {
index = i;
let _ = oper.recv(c1[i].as_ref().unwrap());
break;
}
}
index
};
n[index] += 1;
if n[index] == N {
c1[index] = None;
}
}
wg.done();
});
go!(c, wg, {
let mut n = [0; 4];
let mut c1 = c.iter().map(|c| Some(c.tx().clone())).collect::<Vec<_>>();
for _ in 0..4 * N {
let index = {
let mut sel = Select::new();
let mut opers = [!0; 4];
for &i in &[0, 1, 2, 3] {
if let Some(c) = &c1[i] {
opers[i] = sel.send(c);
}
}
let oper = sel.select();
let mut index = !0;
for i in 0..4 {
if opers[i] == oper.index() {
index = i;
let _ = oper.send(c1[i].as_ref().unwrap(), 0);
break;
}
}
index
};
n[index] += 1;
if n[index] == N {
c1[index] = None;
}
}
wg.done();
});
wg.wait();
}
#[test]
fn test_select_fairness() {
#[cfg(miri)]
const TRIALS: usize = 100;
#[cfg(not(miri))]
const TRIALS: usize = 10000;
let c1 = make::<u8>(TRIALS + 1);
let c2 = make::<u8>(TRIALS + 1);
for _ in 0..TRIALS + 1 {
c1.send(1);
c2.send(2);
}
let c3 = make::<u8>(0);
let c4 = make::<u8>(0);
let out = make::<u8>(0);
let done = make::<u8>(0);
let wg = WaitGroup::new();
wg.add(1);
go!(wg, c1, c2, c3, c4, out, done, {
defer! { wg.done() };
loop {
let b;
select! {
recv(c3.rx()) -> m => b = m.unwrap(),
recv(c4.rx()) -> m => b = m.unwrap(),
recv(c1.rx()) -> m => b = m.unwrap(),
recv(c2.rx()) -> m => b = m.unwrap(),
}
select! {
send(out.tx(), b) -> _ => {}
recv(done.rx()) -> _ => return,
}
}
});
let (mut cnt1, mut cnt2) = (0, 0);
for _ in 0..TRIALS {
match out.recv() {
Some(1) => cnt1 += 1,
Some(2) => cnt2 += 1,
b => panic!("unexpected value {:?} on channel", b),
}
}
// If the select in the goroutine is fair,
// cnt1 and cnt2 should be about the same value.
// With 10,000 trials, the expected margin of error at
// a confidence level of five nines is 4.4172 / (2 * Sqrt(10000)).
let r = cnt1 as f64 / TRIALS as f64;
let e = (r - 0.5).abs();
if e > 4.4172 / (2.0 * (TRIALS as f64).sqrt()) {
panic!(
"unfair select: in {} trials, results were {}, {}",
TRIALS, cnt1, cnt2,
);
}
done.close_s();
wg.wait();
}
#[test]
fn test_chan_send_interface() {
struct Mt;
let c = make::<Box<dyn Any>>(1);
c.send(Box::new(Mt));
select! {
send(c.tx(), Box::new(Mt)) -> _ => {}
default => {}
}
select! {
send(c.tx(), Box::new(Mt)) -> _ => {}
send(c.tx(), Box::new(Mt)) -> _ => {}
default => {}
}
}
#[test]
fn test_pseudo_random_send() {
#[cfg(miri)]
const N: usize = 20;
#[cfg(not(miri))]
const N: usize = 100;
for cap in 0..N {
let c = make::<i32>(cap);
let l = Arc::new(Mutex::new(vec![0i32; N]));
let done = make::<bool>(0);
go!(c, done, l, {
let mut l = l.lock().unwrap();
for i in 0..N {
thread::yield_now();
l[i] = c.recv().unwrap();
}
done.send(true);
});
for _ in 0..N {
select! {
send(c.tx(), 1) -> _ => {}
send(c.tx(), 0) -> _ => {}
}
}
done.recv();
let mut n0 = 0;
let mut n1 = 0;
for &i in l.lock().unwrap().iter() {
n0 += (i + 1) % 2;
n1 += i;
}
if n0 <= N as i32 / 10 || n1 <= N as i32 / 10 {
panic!(
"Want pseudorandom, got {} zeros and {} ones (chan cap {})",
n0, n1, cap,
);
}
}
}
#[test]
fn test_multi_consumer() {
const NWORK: usize = 23;
#[cfg(miri)]
const NITER: usize = 50;
#[cfg(not(miri))]
const NITER: usize = 271828;
let pn = [2, 3, 7, 11, 13, 17, 19, 23, 27, 31];
let q = make::<i32>(NWORK * 3);
let r = make::<i32>(NWORK * 3);
let wg = WaitGroup::new();
for i in 0..NWORK {
wg.add(1);
let w = i;
go!(q, r, wg, pn, {
for v in &q {
if pn[w % pn.len()] == v {
thread::yield_now();
}
r.send(v);
}
wg.done();
});
}
let expect = Arc::new(Mutex::new(0));
go!(q, r, expect, wg, pn, {
for i in 0..NITER {
let v = pn[i % pn.len()];
*expect.lock().unwrap() += v;
q.send(v);
}
q.close_s();
wg.wait();
r.close_s();
});
let mut n = 0;
let mut s = 0;
for v in &r {
n += 1;
s += v;
}
if n != NITER || s != *expect.lock().unwrap() {
panic!();
}
}
#[test]
fn test_select_duplicate_channel() {
// This test makes sure we can queue a G on
// the same channel multiple times.
let c = make::<i32>(0);
let d = make::<i32>(0);
let e = make::<i32>(0);
go!(c, d, e, {
select! {
recv(c.rx()) -> _ => {}
recv(d.rx()) -> _ => {}
recv(e.rx()) -> _ => {}
}
e.send(9);
});
thread::sleep(ms(1));
go!(c, c.recv());
thread::sleep(ms(1));
d.send(7);
e.recv();
c.send(8);
}
}
mod closedchan {
// TODO
}
mod chanbarrier_test {
// TODO
}
mod race_chan_test {
// TODO
}
mod chan {
use super::*;
const MESSAGES_PER_CHANEL: u32 = 76;
const MESSAGES_RANGE_LEN: u32 = 100;
const END: i32 = 10000;
struct ChanWithVals {
chan: Chan<i32>,
/// Next value to send
sv: Arc<AtomicI32>,
/// Next value to receive
rv: Arc<AtomicI32>,
}
struct Totals {
/// Total sent messages
tots: u32,
/// Total received messages
totr: u32,
}
struct Context {
nproc: Arc<Mutex<i32>>,
cval: Arc<Mutex<i32>>,
tot: Arc<Mutex<Totals>>,
nc: ChanWithVals,
randx: Arc<Mutex<i32>>,
}
impl ChanWithVals {
fn with_capacity(capacity: usize) -> Self {
ChanWithVals {
chan: make(capacity),
sv: Arc::new(AtomicI32::new(0)),
rv: Arc::new(AtomicI32::new(0)),
}
}
fn closed() -> Self {
let ch = ChanWithVals::with_capacity(0);
ch.chan.close_r();
ch.chan.close_s();
ch
}
fn rv(&self) -> i32 {
self.rv.load(SeqCst)
}
fn sv(&self) -> i32 {
self.sv.load(SeqCst)
}
fn send(&mut self, tot: &Mutex<Totals>) -> bool {
{
let mut tot = tot.lock().unwrap();
tot.tots += 1
}
let esv = expect(self.sv(), self.sv());
self.sv.store(esv, SeqCst);
if self.sv() == END {
self.chan.close_s();
return true;
}
false
}
fn recv(&mut self, v: i32, tot: &Mutex<Totals>) -> bool {
{
let mut tot = tot.lock().unwrap();
tot.totr += 1
}
let erv = expect(self.rv(), v);
self.rv.store(erv, SeqCst);
if self.rv() == END {
self.chan.close_r();
return true;
}
false
}
}
impl Clone for ChanWithVals {
fn clone(&self) -> Self {
ChanWithVals {
chan: self.chan.clone(),
sv: self.sv.clone(),
rv: self.rv.clone(),
}
}
}
impl Context {
fn nproc(&self) -> &Mutex<i32> {
self.nproc.as_ref()
}
fn cval(&self) -> &Mutex<i32> {
self.cval.as_ref()
}
fn tot(&self) -> &Mutex<Totals> {
self.tot.as_ref()
}
fn randx(&self) -> &Mutex<i32> {
self.randx.as_ref()
}
}
impl Clone for Context {
fn clone(&self) -> Self {
Context {
nproc: self.nproc.clone(),
cval: self.cval.clone(),
tot: self.tot.clone(),
nc: self.nc.clone(),
randx: self.randx.clone(),
}
}
}
fn nrand(n: i32, randx: &Mutex<i32>) -> i32 {
let mut randx = randx.lock().unwrap();
*randx += 10007;
if *randx >= 1000000 {
*randx -= 1000000
}
*randx % n
}
fn change_nproc(adjust: i32, nproc: &Mutex<i32>) -> i32 {
let mut nproc = nproc.lock().unwrap();
*nproc += adjust;
*nproc
}
fn mkchan(c: usize, n: usize, cval: &Mutex<i32>) -> Vec<ChanWithVals> {
let mut ca = Vec::<ChanWithVals>::with_capacity(n);
let mut cval = cval.lock().unwrap();
for _ in 0..n {
*cval += MESSAGES_RANGE_LEN as i32;
let chl = ChanWithVals::with_capacity(c);
chl.sv.store(*cval, SeqCst);
chl.rv.store(*cval, SeqCst);
ca.push(chl);
}
ca
}
fn expect(v: i32, v0: i32) -> i32 {
if v == v0 {
return if v % MESSAGES_RANGE_LEN as i32 == MESSAGES_PER_CHANEL as i32 - 1 {
END
} else {
v + 1
};
}
panic!("got {}, expected {}", v, v0 + 1);
}
fn send(mut c: ChanWithVals, ctx: Context) {
loop {
for _ in 0..=nrand(10, ctx.randx()) {
thread::yield_now();
}
c.chan.tx().send(c.sv()).unwrap();
if c.send(ctx.tot()) {
break;
}
}
change_nproc(-1, ctx.nproc());
}
fn recv(mut c: ChanWithVals, ctx: Context) {
loop {
for _ in (0..nrand(10, ctx.randx())).rev() {
thread::yield_now();
}
let v = c.chan.rx().recv().unwrap();
if c.recv(v, ctx.tot()) {
break;
}
}
change_nproc(-1, ctx.nproc());
}
#[allow(clippy::too_many_arguments)]
fn sel(
mut r0: ChanWithVals,
mut r1: ChanWithVals,
mut r2: ChanWithVals,
mut r3: ChanWithVals,
mut s0: ChanWithVals,
mut s1: ChanWithVals,
mut s2: ChanWithVals,
mut s3: ChanWithVals,
ctx: Context,
) {
let mut a = 0; // local chans running
if r0.chan.has_rx() {
a += 1;
}
if r1.chan.has_rx() {
a += 1;
}
if r2.chan.has_rx() {
a += 1;
}
if r3.chan.has_rx() {
a += 1;
}
if s0.chan.has_tx() {
a += 1;
}
if s1.chan.has_tx() {
a += 1;
}
if s2.chan.has_tx() {
a += 1;
}
if s3.chan.has_tx() {
a += 1;
}
loop {
for _ in 0..=nrand(5, ctx.randx()) {
thread::yield_now();
}
select! {
recv(r0.chan.rx()) -> v => if r0.recv(v.unwrap(), ctx.tot()) { a -= 1 },
recv(r1.chan.rx()) -> v => if r1.recv(v.unwrap(), ctx.tot()) { a -= 1 },
recv(r2.chan.rx()) -> v => if r2.recv(v.unwrap(), ctx.tot()) { a -= 1 },
recv(r3.chan.rx()) -> v => if r3.recv(v.unwrap(), ctx.tot()) { a -= 1 },
send(s0.chan.tx(), s0.sv()) -> _ => if s0.send(ctx.tot()) { a -= 1 },
send(s1.chan.tx(), s1.sv()) -> _ => if s1.send(ctx.tot()) { a -= 1 },
send(s2.chan.tx(), s2.sv()) -> _ => if s2.send(ctx.tot()) { a -= 1 },
send(s3.chan.tx(), s3.sv()) -> _ => if s3.send(ctx.tot()) { a -= 1 },
}
if a == 0 {
break;
}
}
change_nproc(-1, ctx.nproc());
}
fn get(vec: &[ChanWithVals], idx: usize) -> ChanWithVals {
vec.get(idx).unwrap().clone()
}
/// Direct send to direct recv
fn test1(c: ChanWithVals, ctx: &mut Context) {
change_nproc(2, ctx.nproc());
go!(c, ctx, send(c, ctx));
go!(c, ctx, recv(c, ctx));
}
/// Direct send to select recv
fn test2(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 4, ctx.cval());
change_nproc(4, ctx.nproc());
go!(ca, ctx, send(get(&ca, 0), ctx));
go!(ca, ctx, send(get(&ca, 1), ctx));
go!(ca, ctx, send(get(&ca, 2), ctx));
go!(ca, ctx, send(get(&ca, 3), ctx));
change_nproc(1, ctx.nproc());
go!(
ca,
ctx,
sel(
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx,
)
);
}
/// Select send to direct recv
fn test3(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 4, ctx.cval());
change_nproc(4, ctx.nproc());
go!(ca, ctx, recv(get(&ca, 0), ctx));
go!(ca, ctx, recv(get(&ca, 1), ctx));
go!(ca, ctx, recv(get(&ca, 2), ctx));
go!(ca, ctx, recv(get(&ca, 3), ctx));
change_nproc(1, ctx.nproc());
go!(
ca,
ctx,
sel(
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx,
)
);
}
/// Select send to select recv, 4 channels
fn test4(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 4, ctx.cval());
change_nproc(2, ctx.nproc());
go!(
ca,
ctx,
sel(
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx,
)
);
go!(
ca,
ctx,
sel(
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx.nc.clone(),
ctx,
)
);
}
/// Select send to select recv, 8 channels
fn test5(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 8, ctx.cval());
change_nproc(2, ctx.nproc());
go!(
ca,
ctx,
sel(
get(&ca, 4),
get(&ca, 5),
get(&ca, 6),
get(&ca, 7),
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx,
)
);
go!(
ca,
ctx,
sel(
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
get(&ca, 4),
get(&ca, 5),
get(&ca, 6),
get(&ca, 7),
ctx,
)
);
}
// Direct and select send to direct and select recv
fn test6(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 12, ctx.cval());
change_nproc(4, ctx.nproc());
go!(ca, ctx, send(get(&ca, 4), ctx));
go!(ca, ctx, send(get(&ca, 5), ctx));
go!(ca, ctx, send(get(&ca, 6), ctx));
go!(ca, ctx, send(get(&ca, 7), ctx));
change_nproc(4, ctx.nproc());
go!(ca, ctx, recv(get(&ca, 8), ctx));
go!(ca, ctx, recv(get(&ca, 9), ctx));
go!(ca, ctx, recv(get(&ca, 10), ctx));
go!(ca, ctx, recv(get(&ca, 11), ctx));
change_nproc(2, ctx.nproc());
go!(
ca,
ctx,
sel(
get(&ca, 4),
get(&ca, 5),
get(&ca, 6),
get(&ca, 7),
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
ctx,
)
);
go!(
ca,
ctx,
sel(
get(&ca, 0),
get(&ca, 1),
get(&ca, 2),
get(&ca, 3),
get(&ca, 8),
get(&ca, 9),
get(&ca, 10),
get(&ca, 11),
ctx,
)
);
}
fn wait(ctx: &mut Context) {
thread::yield_now();
while change_nproc(0, ctx.nproc()) != 0 {
thread::yield_now();
}
}
fn tests(c: usize, ctx: &mut Context) {
let ca = mkchan(c, 4, ctx.cval());
test1(get(&ca, 0), ctx);
test1(get(&ca, 1), ctx);
test1(get(&ca, 2), ctx);
test1(get(&ca, 3), ctx);
wait(ctx);
test2(c, ctx);
wait(ctx);
test3(c, ctx);
wait(ctx);
test4(c, ctx);
wait(ctx);
test5(c, ctx);
wait(ctx);
test6(c, ctx);
wait(ctx);
}
#[test]
#[cfg_attr(miri, ignore)] // Miri is too slow
fn main() {
let mut ctx = Context {
nproc: Arc::new(Mutex::new(0)),
cval: Arc::new(Mutex::new(0)),
tot: Arc::new(Mutex::new(Totals { tots: 0, totr: 0 })),
nc: ChanWithVals::closed(),
randx: Arc::new(Mutex::new(0)),
};
tests(0, &mut ctx);
tests(1, &mut ctx);
tests(10, &mut ctx);
tests(100, &mut ctx);
#[rustfmt::skip]
let t = 4 * // buffer sizes
(4*4 + // tests 1,2,3,4 channels
8 + // test 5 channels
12) * // test 6 channels
MESSAGES_PER_CHANEL; // sends/recvs on a channel
let tot = ctx.tot.lock().unwrap();
if tot.tots != t || tot.totr != t {
panic!("tots={} totr={} sb={}", tot.tots, tot.totr, t);
}
}
}
mod chan1 {
use super::*;
// sent messages
#[cfg(miri)]
const N: usize = 20;
#[cfg(not(miri))]
const N: usize = 1000;
// receiving "goroutines"
const M: usize = 10;
// channel buffering
const W: usize = 2;
fn r(c: Chan<usize>, m: usize, h: Arc<Mutex<[usize; N]>>) {
loop {
select! {
recv(c.rx()) -> rr => {
let r = rr.unwrap();
let mut data = h.lock().unwrap();
if data[r] != 1 {
println!("r\nm={}\nr={}\nh={}\n", m, r, data[r]);
panic!("fail")
}
data[r] = 2;
}
}
}
}
fn s(c: Chan<usize>, h: Arc<Mutex<[usize; N]>>) {
for n in 0..N {
let r = n;
let mut data = h.lock().unwrap();
if data[r] != 0 {
println!("s");
panic!("fail");
}
data[r] = 1;
drop(data);
c.send(r);
}
}
#[test]
fn main() {
let h = Arc::new(Mutex::new([0usize; N]));
let c = make::<usize>(W);
for m in 0..M {
go!(c, h, {
r(c, m, h);
});
thread::yield_now();
}
thread::yield_now();
thread::yield_now();
s(c, h);
}
}