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|
# Setting up the environment
```ocaml
# #require "eio_main";;
```
```ocaml
open Eio.Std
module S = Eio.Stream
exception Cancel
let run fn =
Eio_main.run @@ fun _ ->
fn ()
let add t v =
traceln "Adding %d to stream" v;
S.add t v;
traceln "Added %d to stream" v
let take t =
traceln "Reading from stream";
traceln "Got %d from stream" (S.take t)
let take_nonblocking t =
traceln "Reading from stream";
traceln "Got %a from stream" Fmt.(option ~none:(any "None") int) (S.take_nonblocking t)
```
# Test cases
Simple non-blocking case
```ocaml
# run @@ fun () ->
let t = S.create 2 in
add t 1;
add t 2;
take t;
take t;;
+Adding 1 to stream
+Added 1 to stream
+Adding 2 to stream
+Added 2 to stream
+Reading from stream
+Got 1 from stream
+Reading from stream
+Got 2 from stream
- : unit = ()
```
Readers have to wait when the stream is empty:
```ocaml
# run @@ fun () ->
let t = S.create 2 in
add t 1;
Fiber.both
(fun () -> take t; take t)
(fun () -> add t 2);;
+Adding 1 to stream
+Added 1 to stream
+Reading from stream
+Got 1 from stream
+Reading from stream
+Adding 2 to stream
+Added 2 to stream
+Got 2 from stream
- : unit = ()
```
Writers have to wait when the stream is full:
```ocaml
# run @@ fun () ->
let t = S.create 3 in
add t 1;
Fiber.both
(fun () ->
add t 2;
add t 3;
add t 4;
)
(fun () ->
take t;
take t;
take t;
take t
);;
+Adding 1 to stream
+Added 1 to stream
+Adding 2 to stream
+Added 2 to stream
+Adding 3 to stream
+Added 3 to stream
+Adding 4 to stream
+Reading from stream
+Got 1 from stream
+Reading from stream
+Got 2 from stream
+Reading from stream
+Got 3 from stream
+Reading from stream
+Got 4 from stream
+Added 4 to stream
- : unit = ()
```
A zero-length queue is synchronous:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
Fiber.both
(fun () ->
add t 1;
add t 2;
)
(fun () ->
take t;
take t;
);;
+Adding 1 to stream
+Reading from stream
+Got 1 from stream
+Reading from stream
+Added 1 to stream
+Adding 2 to stream
+Added 2 to stream
+Got 2 from stream
- : unit = ()
```
Cancel reading from a stream:
```ocaml
# run @@ fun () ->
let t = S.create 1 in
try
Fiber.both
(fun () -> take t)
(fun () -> raise Cancel);
assert false;
with Cancel ->
traceln "Cancelled";
add t 2;
take t;;
+Reading from stream
+Cancelled
+Adding 2 to stream
+Added 2 to stream
+Reading from stream
+Got 2 from stream
- : unit = ()
```
Cancel writing to a stream:
```ocaml
# run @@ fun () ->
let t = S.create 1 in
try
Fiber.both
(fun () -> add t 1; add t 2)
(fun () -> raise Cancel);
assert false;
with Cancel ->
traceln "Cancelled";
take t;
add t 3;
take t;;
+Adding 1 to stream
+Added 1 to stream
+Adding 2 to stream
+Cancelled
+Reading from stream
+Got 1 from stream
+Adding 3 to stream
+Added 3 to stream
+Reading from stream
+Got 3 from stream
- : unit = ()
```
Cancel writing to a zero-length stream:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
try
Fiber.both
(fun () -> add t 1)
(fun () -> raise Cancel);
assert false;
with Cancel ->
traceln "Cancelled";
Fiber.both
(fun () -> add t 2)
(fun () -> take t);;
+Adding 1 to stream
+Cancelled
+Adding 2 to stream
+Reading from stream
+Got 2 from stream
+Added 2 to stream
- : unit = ()
```
Trying to use a stream with a cancelled context:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
Eio.Cancel.sub @@ fun c ->
Eio.Cancel.cancel c Cancel;
begin try add t 1 with ex -> traceln "%a" Fmt.exn ex end;
begin try take t with ex -> traceln "%a" Fmt.exn ex end;
(* Check we released the mutex correctly: *)
Eio.Cancel.protect @@ fun () ->
Fiber.both
(fun () -> add t 1)
(fun () -> take t)
;;
+Adding 1 to stream
+Cancelled: Cancel
+Reading from stream
+Cancelled: Cancel
+Adding 1 to stream
+Reading from stream
+Got 1 from stream
+Added 1 to stream
- : unit = ()
```
Readers queue up:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
Switch.run @@ fun sw ->
Fiber.fork ~sw (fun () -> take t; traceln "a done");
Fiber.fork ~sw (fun () -> take t; traceln "b done");
Fiber.fork ~sw (fun () -> take t; traceln "c done");
add t 1;
add t 2;
add t 3;;
+Reading from stream
+Reading from stream
+Reading from stream
+Adding 1 to stream
+Added 1 to stream
+Adding 2 to stream
+Added 2 to stream
+Adding 3 to stream
+Added 3 to stream
+Got 1 from stream
+a done
+Got 2 from stream
+b done
+Got 3 from stream
+c done
- : unit = ()
```
Writers queue up:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
Switch.run @@ fun sw ->
Fiber.fork ~sw (fun () -> add t 1);
Fiber.fork ~sw (fun () -> add t 2);
Fiber.fork ~sw (fun () -> add t 3);
take t;
take t;
take t;;
+Adding 1 to stream
+Adding 2 to stream
+Adding 3 to stream
+Reading from stream
+Got 1 from stream
+Reading from stream
+Got 2 from stream
+Reading from stream
+Got 3 from stream
+Added 1 to stream
+Added 2 to stream
+Added 3 to stream
- : unit = ()
```
Cancelling writing to a stream:
```ocaml
# run @@ fun () ->
let t = S.create 1 in
add t 0;
Switch.run @@ fun sw ->
try
Fiber.both
(fun () -> add t 1)
(fun () -> raise Cancel)
with Cancel ->
traceln "Cancelled";
take t;
add t 2;
take t;;
+Adding 0 to stream
+Added 0 to stream
+Adding 1 to stream
+Cancelled
+Reading from stream
+Got 0 from stream
+Adding 2 to stream
+Added 2 to stream
+Reading from stream
+Got 2 from stream
- : unit = ()
```
Non-blocking take:
```ocaml
# run @@ fun () ->
let t = S.create 1 in
take_nonblocking t;
add t 0;
take_nonblocking t;;
+Reading from stream
+Got None from stream
+Adding 0 to stream
+Added 0 to stream
+Reading from stream
+Got 0 from stream
- : unit = ()
```
Non-blocking take with zero-capacity stream:
```ocaml
# run @@ fun () ->
let t = S.create 0 in
take_nonblocking t;
Fiber.both
(fun () -> add t 0)
(fun () -> take_nonblocking t);
take_nonblocking t;;
+Reading from stream
+Got None from stream
+Adding 0 to stream
+Reading from stream
+Got 0 from stream
+Added 0 to stream
+Reading from stream
+Got None from stream
- : unit = ()
```
|
