2014-11-25 08:52:10 -08:00
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// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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//! Native threads
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//!
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//! ## The threading model
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//!
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//! An executing Rust program consists of a collection of native OS threads,
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//! each with their own stack and local state.
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//!
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2014-12-14 00:05:32 -08:00
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//! Communication between threads can be done through
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! [channels](../../std/sync/mpsc/index.html), Rust's message-passing
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2014-12-14 00:05:32 -08:00
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//! types, along with [other forms of thread
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//! synchronization](../../std/sync/index.html) and shared-memory data
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//! structures. In particular, types that are guaranteed to be
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//! threadsafe are easily shared between threads using the
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2014-11-25 08:52:10 -08:00
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//! atomically-reference-counted container,
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//! [`Arc`](../../std/sync/struct.Arc.html).
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//!
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//! Fatal logic errors in Rust cause *thread panic*, during which
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//! a thread will unwind the stack, running destructors and freeing
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//! owned resources. Thread panic is unrecoverable from within
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//! the panicking thread (i.e. there is no 'try/catch' in Rust), but
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//! panic may optionally be detected from a different thread. If
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//! the main thread panics the application will exit with a non-zero
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//! exit code.
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//!
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//! When the main thread of a Rust program terminates, the entire program shuts
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//! down, even if other threads are still running. However, this module provides
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//! convenient facilities for automatically waiting for the termination of a
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//! child thread (i.e., join), described below.
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//!
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//! ## The `Thread` type
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//!
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//! Already-running threads are represented via the `Thread` type, which you can
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//! get in one of two ways:
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//!
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2015-02-17 15:10:25 -08:00
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//! * By spawning a new thread, e.g. using the `thread::spawn` constructor;
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//! * By requesting the current thread, using the `thread::current` function.
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2014-11-25 08:52:10 -08:00
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//!
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//! Threads can be named, and provide some built-in support for low-level
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//! synchronization described below.
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//!
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2015-02-17 15:10:25 -08:00
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//! The `thread::current()` function is available even for threads not spawned
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2014-11-25 08:52:10 -08:00
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//! by the APIs of this module.
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//!
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//! ## Spawning a thread
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//!
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2015-02-17 15:10:25 -08:00
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//! A new thread can be spawned using the `thread::spawn` function:
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2014-11-25 08:52:10 -08:00
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//!
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//! ```rust
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2015-02-17 15:10:25 -08:00
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//! use std::thread;
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2014-11-25 08:52:10 -08:00
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//!
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2015-02-17 15:10:25 -08:00
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//! thread::spawn(move || {
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2014-11-25 08:52:10 -08:00
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//! println!("Hello, World!");
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2014-12-14 00:05:32 -08:00
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//! // some computation here
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//! });
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2014-11-25 08:52:10 -08:00
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//! ```
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//!
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2015-02-17 01:08:53 -08:00
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//! In this example, the spawned thread is "detached" from the current
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//! thread, meaning that it can outlive the thread that spawned
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//! it. (Note, however, that when the main thread terminates all
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//! detached threads are terminated as well.)
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//!
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//! ## Scoped threads
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2014-11-25 08:52:10 -08:00
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//!
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! Often a parent thread uses a child thread to perform some particular task,
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//! and at some point must wait for the child to complete before continuing.
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//! For this scenario, use the `scoped` constructor:
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2014-11-25 08:52:10 -08:00
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//!
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! ```rust
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2015-02-17 15:10:25 -08:00
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//! use std::thread;
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//!
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2015-02-17 15:10:25 -08:00
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//! let guard = thread::scoped(move || {
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! println!("Hello, World!");
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//! // some computation here
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//! });
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//! // do some other work in the meantime
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2015-02-17 15:10:25 -08:00
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//! let output = guard.join();
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! ```
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2014-11-25 08:52:10 -08:00
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//!
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2015-02-17 01:08:53 -08:00
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//! The `scoped` function doesn't return a `Thread` directly; instead,
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//! it returns a *join guard*. The join guard is an RAII-style guard
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//! that will automatically join the child thread (block until it
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//! terminates) when it is dropped. You can join the child thread in
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//! advance by calling the `join` method on the guard, which will also
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//! return the result produced by the thread. A handle to the thread
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//! itself is available via the `thread` method on the join guard.
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2014-11-25 08:52:10 -08:00
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//!
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! (Note: eventually, the `scoped` constructor will allow the parent and child
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//! threads to data that lives on the parent thread's stack, but some language
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//! changes are needed before this is possible.)
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2014-11-25 08:52:10 -08:00
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//!
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2014-12-14 00:05:32 -08:00
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//! ## Configuring threads
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2014-11-25 08:52:10 -08:00
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//!
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2014-12-14 00:05:32 -08:00
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//! A new thread can be configured before it is spawned via the `Builder` type,
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//! which currently allows you to set the name, stack size, and writers for
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//! `println!` and `panic!` for the child thread:
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2014-11-25 08:52:10 -08:00
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//!
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//! ```rust
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//! use std::thread;
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//!
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2014-12-14 00:05:32 -08:00
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//! thread::Builder::new().name("child1".to_string()).spawn(move || {
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//! println!("Hello, world!")
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Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
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//! });
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2014-11-25 08:52:10 -08:00
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//! ```
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//!
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//! ## Blocking support: park and unpark
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//!
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//! Every thread is equipped with some basic low-level blocking support, via the
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//! `park` and `unpark` functions.
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//!
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//! Conceptually, each `Thread` handle has an associated token, which is
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//! initially not present:
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|
|
//!
|
2015-02-17 15:10:25 -08:00
|
|
|
//! * The `thread::park()` function blocks the current thread unless or until
|
2014-11-25 08:52:10 -08:00
|
|
|
//! the token is available for its thread handle, at which point It atomically
|
|
|
|
//! consumes the token. It may also return *spuriously*, without consuming the
|
2015-02-17 15:10:25 -08:00
|
|
|
//! token. `thread::park_timeout()` does the same, but allows specifying a
|
2015-01-30 13:44:13 -08:00
|
|
|
//! maximum time to block the thread for.
|
2014-11-25 08:52:10 -08:00
|
|
|
//!
|
|
|
|
//! * The `unpark()` method on a `Thread` atomically makes the token available
|
|
|
|
//! if it wasn't already.
|
|
|
|
//!
|
|
|
|
//! In other words, each `Thread` acts a bit like a semaphore with initial count
|
|
|
|
//! 0, except that the semaphore is *saturating* (the count cannot go above 1),
|
|
|
|
//! and can return spuriously.
|
|
|
|
//!
|
|
|
|
//! The API is typically used by acquiring a handle to the current thread,
|
|
|
|
//! placing that handle in a shared data structure so that other threads can
|
|
|
|
//! find it, and then `park`ing. When some desired condition is met, another
|
|
|
|
//! thread calls `unpark` on the handle.
|
|
|
|
//!
|
|
|
|
//! The motivation for this design is twofold:
|
|
|
|
//!
|
|
|
|
//! * It avoids the need to allocate mutexes and condvars when building new
|
|
|
|
//! synchronization primitives; the threads already provide basic blocking/signaling.
|
|
|
|
//!
|
|
|
|
//! * It can be implemented highly efficiently on many platforms.
|
|
|
|
|
2015-01-23 21:48:20 -08:00
|
|
|
#![stable(feature = "rust1", since = "1.0.0")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
|
2015-02-17 15:24:34 -08:00
|
|
|
use prelude::v1::*;
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
use any::Any;
|
2014-12-22 17:15:51 +01:00
|
|
|
use cell::UnsafeCell;
|
2015-02-17 01:08:53 -08:00
|
|
|
use fmt;
|
|
|
|
use io;
|
2015-02-17 15:24:34 -08:00
|
|
|
use marker;
|
|
|
|
use old_io::stdio;
|
2015-01-03 22:42:21 -05:00
|
|
|
use rt::{self, unwind};
|
2015-02-17 15:24:34 -08:00
|
|
|
use sync::{Mutex, Condvar, Arc};
|
2014-12-14 00:05:32 -08:00
|
|
|
use thunk::Thunk;
|
2015-01-30 13:44:13 -08:00
|
|
|
use time::Duration;
|
2014-11-25 08:52:10 -08:00
|
|
|
|
|
|
|
use sys::thread as imp;
|
|
|
|
use sys_common::{stack, thread_info};
|
|
|
|
|
2015-01-06 20:53:18 -05:00
|
|
|
/// Thread configuration. Provides detailed control over the properties
|
2014-11-25 08:52:10 -08:00
|
|
|
/// and behavior of new threads.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub struct Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
// A name for the thread-to-be, for identification in panic messages
|
|
|
|
name: Option<String>,
|
|
|
|
// The size of the stack for the spawned thread
|
|
|
|
stack_size: Option<uint>,
|
|
|
|
// Thread-local stdout
|
2015-02-13 22:58:37 +11:00
|
|
|
stdout: Option<Box<Writer + Send + 'static>>,
|
2014-11-25 08:52:10 -08:00
|
|
|
// Thread-local stderr
|
2015-02-13 22:58:37 +11:00
|
|
|
stderr: Option<Box<Writer + Send + 'static>>,
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2014-12-14 00:05:32 -08:00
|
|
|
impl Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
/// Generate the base configuration for spawning a thread, from which
|
|
|
|
/// configuration methods can be chained.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub fn new() -> Builder {
|
|
|
|
Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
name: None,
|
|
|
|
stack_size: None,
|
|
|
|
stdout: None,
|
|
|
|
stderr: None,
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Name the thread-to-be. Currently the name is used for identification
|
|
|
|
/// only in panic messages.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub fn name(mut self, name: String) -> Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
self.name = Some(name);
|
|
|
|
self
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Set the size of the stack for the new thread.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub fn stack_size(mut self, size: uint) -> Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
self.stack_size = Some(size);
|
|
|
|
self
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Redirect thread-local stdout.
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc",
|
2015-01-12 18:40:19 -08:00
|
|
|
reason = "Will likely go away after proc removal")]
|
2015-02-13 22:58:37 +11:00
|
|
|
pub fn stdout(mut self, stdout: Box<Writer + Send + 'static>) -> Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
self.stdout = Some(stdout);
|
|
|
|
self
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Redirect thread-local stderr.
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc",
|
2015-01-12 18:40:19 -08:00
|
|
|
reason = "Will likely go away after proc removal")]
|
2015-02-13 22:58:37 +11:00
|
|
|
pub fn stderr(mut self, stderr: Box<Writer + Send + 'static>) -> Builder {
|
2014-11-25 08:52:10 -08:00
|
|
|
self.stderr = Some(stderr);
|
|
|
|
self
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Spawn a new thread, and return a join handle for it.
|
2014-12-14 00:05:32 -08:00
|
|
|
///
|
2015-02-17 01:08:53 -08:00
|
|
|
/// The child thread may outlive the parent (unless the parent thread
|
|
|
|
/// is the main thread; the whole process is terminated when the main
|
|
|
|
/// thread finishes.) The join handle can be used to block on
|
|
|
|
/// termination of the child thread, including recovering its panics.
|
|
|
|
///
|
|
|
|
/// # Errors
|
|
|
|
///
|
|
|
|
/// Unlike the `spawn` free function, this method yields an
|
|
|
|
/// `io::Result` to capture any failure to create the thread at
|
|
|
|
/// the OS level.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn spawn<F>(self, f: F) -> io::Result<JoinHandle> where
|
|
|
|
F: FnOnce(), F: Send + 'static
|
|
|
|
{
|
|
|
|
self.spawn_inner(Thunk::new(f)).map(|i| JoinHandle(i))
|
2014-12-14 00:05:32 -08:00
|
|
|
}
|
|
|
|
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
/// Spawn a new child thread that must be joined within a given
|
|
|
|
/// scope, and return a `JoinGuard`.
|
|
|
|
///
|
2015-02-17 01:08:53 -08:00
|
|
|
/// The join guard can be used to explicitly join the child thread (via
|
|
|
|
/// `join`), returning `Result<T>`, or it will implicitly join the child
|
|
|
|
/// upon being dropped. Because the child thread may refer to data on the
|
|
|
|
/// current thread's stack (hence the "scoped" name), it cannot be detached;
|
|
|
|
/// it *must* be joined before the relevant stack frame is popped. See the
|
|
|
|
/// module documentation for additional details.
|
|
|
|
///
|
|
|
|
/// # Errors
|
|
|
|
///
|
|
|
|
/// Unlike the `scoped` free function, this method yields an
|
|
|
|
/// `io::Result` to capture any failure to create the thread at
|
|
|
|
/// the OS level.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn scoped<'a, T, F>(self, f: F) -> io::Result<JoinGuard<'a, T>> where
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
T: Send + 'a, F: FnOnce() -> T, F: Send + 'a
|
|
|
|
{
|
2015-02-17 15:24:34 -08:00
|
|
|
self.spawn_inner(Thunk::new(f)).map(|inner| {
|
|
|
|
JoinGuard { inner: inner, _marker: marker::PhantomData }
|
|
|
|
})
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
fn spawn_inner<T: Send>(self, f: Thunk<(), T>) -> io::Result<JoinInner<T>> {
|
2014-12-14 00:05:32 -08:00
|
|
|
let Builder { name, stack_size, stdout, stderr } = self;
|
2014-11-25 08:52:10 -08:00
|
|
|
|
|
|
|
let stack_size = stack_size.unwrap_or(rt::min_stack());
|
2015-02-17 01:08:53 -08:00
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
let my_thread = Thread::new(name);
|
|
|
|
let their_thread = my_thread.clone();
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
let my_packet = Packet(Arc::new(UnsafeCell::new(None)));
|
|
|
|
let their_packet = Packet(my_packet.0.clone());
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
// Spawning a new OS thread guarantees that __morestack will never get
|
|
|
|
// triggered, but we must manually set up the actual stack bounds once
|
|
|
|
// this function starts executing. This raises the lower limit by a bit
|
|
|
|
// because by the time that this function is executing we've already
|
|
|
|
// consumed at least a little bit of stack (we don't know the exact byte
|
|
|
|
// address at which our stack started).
|
2015-02-01 12:44:15 -05:00
|
|
|
let main = move || {
|
2014-11-25 08:52:10 -08:00
|
|
|
let something_around_the_top_of_the_stack = 1;
|
|
|
|
let addr = &something_around_the_top_of_the_stack as *const int;
|
|
|
|
let my_stack_top = addr as uint;
|
|
|
|
let my_stack_bottom = my_stack_top - stack_size + 1024;
|
|
|
|
unsafe {
|
|
|
|
stack::record_os_managed_stack_bounds(my_stack_bottom, my_stack_top);
|
|
|
|
}
|
2015-02-04 02:26:00 +01:00
|
|
|
match their_thread.name() {
|
|
|
|
Some(name) => unsafe { imp::set_name(name.as_slice()); },
|
|
|
|
None => {}
|
|
|
|
}
|
2014-11-25 08:52:10 -08:00
|
|
|
thread_info::set(
|
|
|
|
(my_stack_bottom, my_stack_top),
|
2014-12-06 18:34:37 -08:00
|
|
|
unsafe { imp::guard::current() },
|
2014-11-25 08:52:10 -08:00
|
|
|
their_thread
|
|
|
|
);
|
|
|
|
|
2014-12-14 00:05:32 -08:00
|
|
|
let mut output = None;
|
|
|
|
let f: Thunk<(), T> = if stdout.is_some() || stderr.is_some() {
|
2015-02-01 12:44:15 -05:00
|
|
|
Thunk::new(move || {
|
2014-12-14 00:05:32 -08:00
|
|
|
let _ = stdout.map(stdio::set_stdout);
|
|
|
|
let _ = stderr.map(stdio::set_stderr);
|
|
|
|
f.invoke(())
|
|
|
|
})
|
|
|
|
} else {
|
|
|
|
f
|
|
|
|
};
|
|
|
|
|
|
|
|
let try_result = {
|
|
|
|
let ptr = &mut output;
|
|
|
|
|
|
|
|
// There are two primary reasons that general try/catch is
|
|
|
|
// unsafe. The first is that we do not support nested
|
|
|
|
// try/catch. The fact that this is happening in a newly-spawned
|
|
|
|
// thread suffices. The second is that unwinding while unwinding
|
|
|
|
// is not defined. We take care of that by having an
|
|
|
|
// 'unwinding' flag in the thread itself. For these reasons,
|
|
|
|
// this unsafety should be ok.
|
|
|
|
unsafe {
|
|
|
|
unwind::try(move || *ptr = Some(f.invoke(())))
|
|
|
|
}
|
|
|
|
};
|
2015-02-17 01:08:53 -08:00
|
|
|
unsafe {
|
|
|
|
*their_packet.0.get() = Some(match (output, try_result) {
|
|
|
|
(Some(data), Ok(_)) => Ok(data),
|
|
|
|
(None, Err(cause)) => Err(cause),
|
|
|
|
_ => unreachable!()
|
|
|
|
});
|
|
|
|
}
|
2014-11-25 08:52:10 -08:00
|
|
|
};
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
Ok(JoinInner {
|
|
|
|
native: try!(unsafe { imp::create(stack_size, Thunk::new(main)) }),
|
|
|
|
thread: my_thread,
|
|
|
|
packet: my_packet,
|
|
|
|
joined: false,
|
|
|
|
})
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Spawn a new, returning a join handle for it.
|
|
|
|
///
|
|
|
|
/// The child thread may outlive the parent (unless the parent thread
|
|
|
|
/// is the main thread; the whole process is terminated when the main
|
|
|
|
/// thread finishes.) The join handle can be used to block on
|
|
|
|
/// termination of the child thread, including recovering its panics.
|
|
|
|
///
|
|
|
|
/// # Panics
|
|
|
|
///
|
|
|
|
/// Panicks if the OS fails to create a thread; use `Builder::spawn`
|
|
|
|
/// to recover from such errors.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn spawn<F>(f: F) -> JoinHandle where F: FnOnce(), F: Send + 'static {
|
|
|
|
Builder::new().spawn(f).unwrap()
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Spawn a new *scoped* thread, returning a `JoinGuard` for it.
|
|
|
|
///
|
|
|
|
/// The join guard can be used to explicitly join the child thread (via
|
|
|
|
/// `join`), returning `Result<T>`, or it will implicitly join the child
|
|
|
|
/// upon being dropped. Because the child thread may refer to data on the
|
|
|
|
/// current thread's stack (hence the "scoped" name), it cannot be detached;
|
|
|
|
/// it *must* be joined before the relevant stack frame is popped. See the
|
|
|
|
/// module documentation for additional details.
|
|
|
|
///
|
|
|
|
/// # Panics
|
|
|
|
///
|
|
|
|
/// Panicks if the OS fails to create a thread; use `Builder::scoped`
|
|
|
|
/// to recover from such errors.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn scoped<'a, T, F>(f: F) -> JoinGuard<'a, T> where
|
|
|
|
T: Send + 'a, F: FnOnce() -> T, F: Send + 'a
|
|
|
|
{
|
|
|
|
Builder::new().scoped(f).unwrap()
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Gets a handle to the thread that invokes it.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn current() -> Thread {
|
|
|
|
thread_info::current_thread()
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Cooperatively give up a timeslice to the OS scheduler.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn yield_now() {
|
|
|
|
unsafe { imp::yield_now() }
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Determines whether the current thread is unwinding because of panic.
|
|
|
|
#[inline]
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn panicking() -> bool {
|
|
|
|
unwind::panicking()
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Block unless or until the current thread's token is made available (may wake spuriously).
|
|
|
|
///
|
|
|
|
/// See the module doc for more detail.
|
|
|
|
//
|
|
|
|
// The implementation currently uses the trivial strategy of a Mutex+Condvar
|
|
|
|
// with wakeup flag, which does not actually allow spurious wakeups. In the
|
|
|
|
// future, this will be implemented in a more efficient way, perhaps along the lines of
|
|
|
|
// http://cr.openjdk.java.net/~stefank/6989984.1/raw_files/new/src/os/linux/vm/os_linux.cpp
|
|
|
|
// or futuxes, and in either case may allow spurious wakeups.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn park() {
|
2015-02-17 15:10:25 -08:00
|
|
|
let thread = current();
|
2015-02-17 01:08:53 -08:00
|
|
|
let mut guard = thread.inner.lock.lock().unwrap();
|
|
|
|
while !*guard {
|
|
|
|
guard = thread.inner.cvar.wait(guard).unwrap();
|
|
|
|
}
|
|
|
|
*guard = false;
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Block unless or until the current thread's token is made available or
|
|
|
|
/// the specified duration has been reached (may wake spuriously).
|
|
|
|
///
|
|
|
|
/// The semantics of this function are equivalent to `park()` except that the
|
|
|
|
/// thread will be blocked for roughly no longer than dur. This method
|
|
|
|
/// should not be used for precise timing due to anomalies such as
|
|
|
|
/// preemption or platform differences that may not cause the maximum
|
|
|
|
/// amount of time waited to be precisely dur
|
|
|
|
///
|
|
|
|
/// See the module doc for more detail.
|
|
|
|
#[unstable(feature = "std_misc", reason = "recently introduced, depends on Duration")]
|
|
|
|
pub fn park_timeout(dur: Duration) {
|
2015-02-17 15:10:25 -08:00
|
|
|
let thread = current();
|
2015-02-17 01:08:53 -08:00
|
|
|
let mut guard = thread.inner.lock.lock().unwrap();
|
|
|
|
if !*guard {
|
|
|
|
let (g, _) = thread.inner.cvar.wait_timeout(guard, dur).unwrap();
|
|
|
|
guard = g;
|
|
|
|
}
|
|
|
|
*guard = false;
|
|
|
|
}
|
|
|
|
|
|
|
|
/// The internal representation of a `Thread` handle
|
2014-11-25 08:52:10 -08:00
|
|
|
struct Inner {
|
|
|
|
name: Option<String>,
|
|
|
|
lock: Mutex<bool>, // true when there is a buffered unpark
|
|
|
|
cvar: Condvar,
|
|
|
|
}
|
|
|
|
|
2014-12-22 00:49:42 +01:00
|
|
|
unsafe impl Sync for Inner {}
|
|
|
|
|
2015-01-03 22:54:18 -05:00
|
|
|
#[derive(Clone)]
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-11-25 08:52:10 -08:00
|
|
|
/// A handle to a thread.
|
|
|
|
pub struct Thread {
|
|
|
|
inner: Arc<Inner>,
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Thread {
|
2014-12-14 00:05:32 -08:00
|
|
|
// Used only internally to construct a thread object without spawning
|
2014-11-25 08:52:10 -08:00
|
|
|
fn new(name: Option<String>) -> Thread {
|
|
|
|
Thread {
|
|
|
|
inner: Arc::new(Inner {
|
|
|
|
name: name,
|
|
|
|
lock: Mutex::new(false),
|
|
|
|
cvar: Condvar::new(),
|
|
|
|
})
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc",
|
2015-01-12 18:40:19 -08:00
|
|
|
reason = "may change with specifics of new Send semantics")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
pub fn spawn<F>(f: F) -> Thread where F: FnOnce(), F: Send + 'static {
|
2015-02-17 01:08:53 -08:00
|
|
|
Builder::new().spawn(f).unwrap().thread().clone()
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc",
|
2015-01-12 18:40:19 -08:00
|
|
|
reason = "may change with specifics of new Send semantics")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
pub fn scoped<'a, T, F>(f: F) -> JoinGuard<'a, T> where
|
|
|
|
T: Send + 'a, F: FnOnce() -> T, F: Send + 'a
|
2014-12-14 00:05:32 -08:00
|
|
|
{
|
2015-02-17 01:08:53 -08:00
|
|
|
Builder::new().scoped(f).unwrap()
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn current() -> Thread {
|
2014-12-06 18:34:37 -08:00
|
|
|
thread_info::current_thread()
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc", reason = "name may change")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn yield_now() {
|
|
|
|
unsafe { imp::yield_now() }
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2014-12-08 20:20:03 -08:00
|
|
|
#[inline]
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn panicking() -> bool {
|
2014-12-17 14:59:20 -08:00
|
|
|
unwind::panicking()
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-22 18:22:03 -08:00
|
|
|
#[unstable(feature = "std_misc", reason = "recently introduced")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn park() {
|
2015-02-17 15:10:25 -08:00
|
|
|
let thread = current();
|
2014-12-08 20:20:03 -08:00
|
|
|
let mut guard = thread.inner.lock.lock().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
while !*guard {
|
2014-12-08 20:20:03 -08:00
|
|
|
guard = thread.inner.cvar.wait(guard).unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
*guard = false;
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Deprecated: use module-level free fucntion.
|
|
|
|
#[deprecated(since = "1.0.0", reason = "use module-level free fucntion")]
|
2015-01-30 13:44:13 -08:00
|
|
|
#[unstable(feature = "std_misc", reason = "recently introduced")]
|
|
|
|
pub fn park_timeout(dur: Duration) {
|
2015-02-17 15:10:25 -08:00
|
|
|
let thread = current();
|
2015-01-30 13:44:13 -08:00
|
|
|
let mut guard = thread.inner.lock.lock().unwrap();
|
|
|
|
if !*guard {
|
|
|
|
let (g, _) = thread.inner.cvar.wait_timeout(guard, dur).unwrap();
|
|
|
|
guard = g;
|
|
|
|
}
|
|
|
|
*guard = false;
|
|
|
|
}
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
/// Atomically makes the handle's token available if it is not already.
|
|
|
|
///
|
|
|
|
/// See the module doc for more detail.
|
2015-02-17 01:08:53 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn unpark(&self) {
|
2014-12-08 20:20:03 -08:00
|
|
|
let mut guard = self.inner.lock.lock().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
if !*guard {
|
|
|
|
*guard = true;
|
|
|
|
self.inner.cvar.notify_one();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Get the thread's name.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-11-25 08:52:10 -08:00
|
|
|
pub fn name(&self) -> Option<&str> {
|
2015-02-01 21:53:25 -05:00
|
|
|
self.inner.name.as_ref().map(|s| &**s)
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
impl fmt::Debug for Thread {
|
|
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
|
|
fmt::Debug::fmt(&self.name(), f)
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
// a hack to get around privacy restrictions
|
|
|
|
impl thread_info::NewThread for Thread {
|
|
|
|
fn new(name: Option<String>) -> Thread { Thread::new(name) }
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Indicates the manner in which a thread exited.
|
|
|
|
///
|
|
|
|
/// A thread that completes without panicking is considered to exit successfully.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2015-02-13 22:58:37 +11:00
|
|
|
pub type Result<T> = ::result::Result<T, Box<Any + Send + 'static>>;
|
2014-11-25 08:52:10 -08:00
|
|
|
|
2014-12-22 17:15:51 +01:00
|
|
|
struct Packet<T>(Arc<UnsafeCell<Option<Result<T>>>>);
|
|
|
|
|
2015-02-13 22:58:37 +11:00
|
|
|
unsafe impl<T:Send> Send for Packet<T> {}
|
2014-12-22 17:15:51 +01:00
|
|
|
unsafe impl<T> Sync for Packet<T> {}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// Inner representation for JoinHandle and JoinGuard
|
|
|
|
struct JoinInner<T> {
|
2014-11-25 08:52:10 -08:00
|
|
|
native: imp::rust_thread,
|
|
|
|
thread: Thread,
|
2014-12-22 17:15:51 +01:00
|
|
|
packet: Packet<T>,
|
2015-02-17 01:08:53 -08:00
|
|
|
joined: bool,
|
|
|
|
}
|
|
|
|
|
|
|
|
impl<T> JoinInner<T> {
|
|
|
|
fn join(&mut self) -> Result<T> {
|
|
|
|
assert!(!self.joined);
|
|
|
|
unsafe { imp::join(self.native) };
|
|
|
|
self.joined = true;
|
|
|
|
unsafe {
|
|
|
|
(*self.packet.0.get()).take().unwrap()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/// An owned permission to join on a thread (block on its termination).
|
|
|
|
///
|
|
|
|
/// Unlike a `JoinGuard`, a `JoinHandle` *detaches* the child thread
|
|
|
|
/// when it is dropped, rather than automatically joining on drop.
|
|
|
|
///
|
|
|
|
/// Due to platform restrictions, it is not possible to `Clone` this
|
|
|
|
/// handle: the ability to join a child thread is a uniquely-owned
|
|
|
|
/// permission.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub struct JoinHandle(JoinInner<()>);
|
|
|
|
|
|
|
|
impl JoinHandle {
|
|
|
|
/// Extract a handle to the underlying thread
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn thread(&self) -> &Thread {
|
|
|
|
&self.0.thread
|
|
|
|
}
|
|
|
|
|
|
|
|
/// Wait for the associated thread to finish.
|
|
|
|
///
|
|
|
|
/// If the child thread panics, `Err` is returned with the parameter given
|
|
|
|
/// to `panic`.
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
pub fn join(mut self) -> Result<()> {
|
|
|
|
self.0.join()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
|
|
impl Drop for JoinHandle {
|
|
|
|
fn drop(&mut self) {
|
|
|
|
if !self.0.joined {
|
|
|
|
unsafe { imp::detach(self.0.native) }
|
|
|
|
}
|
|
|
|
}
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
/// An RAII-style guard that will block until thread termination when dropped.
|
|
|
|
///
|
|
|
|
/// The type `T` is the return type for the thread's main function.
|
|
|
|
///
|
|
|
|
/// Joining on drop is necessary to ensure memory safety when stack
|
|
|
|
/// data is shared between a parent and child thread.
|
|
|
|
///
|
|
|
|
/// Due to platform restrictions, it is not possible to `Clone` this
|
|
|
|
/// handle: the ability to join a child thread is a uniquely-owned
|
|
|
|
/// permission.
|
|
|
|
#[must_use]
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2015-02-17 15:24:34 -08:00
|
|
|
pub struct JoinGuard<'a, T: 'a> {
|
|
|
|
inner: JoinInner<T>,
|
|
|
|
_marker: marker::PhantomData<&'a T>,
|
|
|
|
}
|
2015-02-17 01:08:53 -08:00
|
|
|
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
unsafe impl<'a, T: Send + 'a> Sync for JoinGuard<'a, T> {}
|
2014-12-22 17:15:51 +01:00
|
|
|
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
impl<'a, T: Send + 'a> JoinGuard<'a, T> {
|
2014-11-25 08:52:10 -08:00
|
|
|
/// Extract a handle to the thread this guard will join on.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub fn thread(&self) -> &Thread {
|
2015-02-17 15:24:34 -08:00
|
|
|
&self.inner.thread
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
/// Wait for the associated thread to finish, returning the result of the thread's
|
|
|
|
/// calculation.
|
2014-12-14 00:05:32 -08:00
|
|
|
///
|
2015-02-17 01:08:53 -08:00
|
|
|
/// # Panics
|
|
|
|
///
|
|
|
|
/// Panics on the child thread are propagated by panicking the parent.
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
2015-02-17 01:08:53 -08:00
|
|
|
pub fn join(mut self) -> T {
|
2015-02-17 15:24:34 -08:00
|
|
|
match self.inner.join() {
|
2015-02-17 01:08:53 -08:00
|
|
|
Ok(res) => res,
|
|
|
|
Err(_) => panic!("child thread {:?} panicked", self.thread()),
|
2014-12-14 00:05:32 -08:00
|
|
|
}
|
|
|
|
}
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
}
|
2014-12-14 00:05:32 -08:00
|
|
|
|
2015-02-17 01:08:53 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
impl<T: Send> JoinGuard<'static, T> {
|
2014-12-14 00:05:32 -08:00
|
|
|
/// Detaches the child thread, allowing it to outlive its parent.
|
2015-02-17 01:08:53 -08:00
|
|
|
#[deprecated(since = "1.0.0", reason = "use spawn instead")]
|
|
|
|
#[unstable(feature = "std_misc")]
|
2014-12-14 00:05:32 -08:00
|
|
|
pub fn detach(mut self) {
|
2015-02-17 15:24:34 -08:00
|
|
|
unsafe { imp::detach(self.inner.native) };
|
|
|
|
self.inner.joined = true; // avoid joining in the destructor
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[unsafe_destructor]
|
2015-01-23 21:48:20 -08:00
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
Stabilize std::thread
This commit takes a first pass at stabilizing `std::thread`:
* It removes the `detach` method in favor of two constructors -- `spawn`
for detached threads, `scoped` for "scoped" (i.e., must-join)
threads. This addresses some of the surprise/frustrating debug
sessions with the previous API, in which `spawn` produced a guard that
on destruction joined the thread (unless `detach` was called).
The reason to have the division in part is that `Send` will soon not
imply `'static`, which means that `scoped` thread creation can take a
closure over *shared stack data* of the parent thread. On the other
hand, this means that the parent must not pop the relevant stack
frames while the child thread is running. The `JoinGuard` is used to
prevent this from happening by joining on drop (if you have not
already explicitly `join`ed.) The APIs around `scoped` are
future-proofed for the `Send` changes by taking an additional lifetime
parameter. With the current definition of `Send`, this is forced to be
`'static`, but when `Send` changes these APIs will gain their full
flexibility immediately.
Threads that are `spawn`ed, on the other hand, are detached from the
start and do not yield an RAII guard.
The hope is that, by making `scoped` an explicit opt-in with a very
suggestive name, it will be drastically less likely to be caught by a
surprising deadlock due to an implicit join at the end of a scope.
* The module itself is marked stable.
* Existing methods other than `spawn` and `scoped` are marked stable.
The migration path is:
```rust
Thread::spawn(f).detached()
```
becomes
```rust
Thread::spawn(f)
```
while
```rust
let res = Thread::spawn(f);
res.join()
```
becomes
```rust
let res = Thread::scoped(f);
res.join()
```
[breaking-change]
2015-01-05 15:45:18 -08:00
|
|
|
impl<'a, T: Send + 'a> Drop for JoinGuard<'a, T> {
|
2014-11-25 08:52:10 -08:00
|
|
|
fn drop(&mut self) {
|
2015-02-17 15:24:34 -08:00
|
|
|
if !self.inner.joined {
|
|
|
|
unsafe { imp::join(self.inner.native) };
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[cfg(test)]
|
|
|
|
mod test {
|
2014-12-22 09:04:23 -08:00
|
|
|
use prelude::v1::*;
|
|
|
|
|
2015-01-01 01:13:08 -05:00
|
|
|
use any::Any;
|
2014-12-23 11:53:35 -08:00
|
|
|
use sync::mpsc::{channel, Sender};
|
2015-01-02 09:24:56 -08:00
|
|
|
use boxed::BoxAny;
|
2014-11-25 08:52:10 -08:00
|
|
|
use result;
|
2015-01-22 16:31:00 -08:00
|
|
|
use std::old_io::{ChanReader, ChanWriter};
|
2015-02-17 15:10:25 -08:00
|
|
|
use super::{self, Thread, Builder};
|
2014-12-22 09:04:23 -08:00
|
|
|
use thunk::Thunk;
|
2015-01-30 13:44:13 -08:00
|
|
|
use time::Duration;
|
2014-11-25 08:52:10 -08:00
|
|
|
|
|
|
|
// !!! These tests are dangerous. If something is buggy, they will hang, !!!
|
|
|
|
// !!! instead of exiting cleanly. This might wedge the buildbots. !!!
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_unnamed_thread() {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| {
|
|
|
|
assert!(thread::current().name().is_none());
|
2015-01-20 15:45:07 -08:00
|
|
|
}).join().ok().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_named_thread() {
|
2015-01-05 21:59:45 -08:00
|
|
|
Builder::new().name("ada lovelace".to_string()).scoped(move|| {
|
2015-02-17 15:10:25 -08:00
|
|
|
assert!(thread::current().name().unwrap() == "ada lovelace".to_string());
|
2015-01-20 15:45:07 -08:00
|
|
|
}).join().ok().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_run_basic() {
|
|
|
|
let (tx, rx) = channel();
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| {
|
2014-12-23 11:53:35 -08:00
|
|
|
tx.send(()).unwrap();
|
2015-01-05 21:59:45 -08:00
|
|
|
});
|
2014-12-23 11:53:35 -08:00
|
|
|
rx.recv().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_join_success() {
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| -> String {
|
2014-11-25 08:52:10 -08:00
|
|
|
"Success!".to_string()
|
2015-02-01 21:53:25 -05:00
|
|
|
}).join().as_ref().map(|s| &**s) {
|
2014-11-25 08:52:10 -08:00
|
|
|
result::Result::Ok("Success!") => (),
|
|
|
|
_ => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_join_panic() {
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
panic!()
|
|
|
|
}).join() {
|
|
|
|
result::Result::Err(_) => (),
|
|
|
|
result::Result::Ok(()) => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-17 15:10:25 -08:00
|
|
|
#[test]
|
|
|
|
fn test_scoped_success() {
|
|
|
|
let res = thread::scoped(move|| -> String {
|
|
|
|
"Success!".to_string()
|
|
|
|
}).join();
|
|
|
|
assert!(res == "Success!");
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
#[should_fail]
|
|
|
|
fn test_scoped_panic() {
|
|
|
|
thread::scoped(|| panic!()).join();
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
#[should_fail]
|
|
|
|
fn test_scoped_implicit_panic() {
|
|
|
|
thread::scoped(|| panic!());
|
|
|
|
}
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
#[test]
|
|
|
|
fn test_spawn_sched() {
|
|
|
|
use clone::Clone;
|
|
|
|
|
|
|
|
let (tx, rx) = channel();
|
|
|
|
|
|
|
|
fn f(i: int, tx: Sender<()>) {
|
|
|
|
let tx = tx.clone();
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
if i == 0 {
|
2014-12-23 11:53:35 -08:00
|
|
|
tx.send(()).unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
} else {
|
|
|
|
f(i - 1, tx);
|
|
|
|
}
|
2015-01-05 21:59:45 -08:00
|
|
|
});
|
2014-11-25 08:52:10 -08:00
|
|
|
|
|
|
|
}
|
|
|
|
f(10, tx);
|
2014-12-23 11:53:35 -08:00
|
|
|
rx.recv().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_spawn_sched_childs_on_default_sched() {
|
|
|
|
let (tx, rx) = channel();
|
|
|
|
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| {
|
|
|
|
thread::spawn(move|| {
|
2014-12-23 11:53:35 -08:00
|
|
|
tx.send(()).unwrap();
|
2015-01-05 21:59:45 -08:00
|
|
|
});
|
|
|
|
});
|
2014-11-25 08:52:10 -08:00
|
|
|
|
2014-12-23 11:53:35 -08:00
|
|
|
rx.recv().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
2015-02-17 23:48:32 +11:00
|
|
|
fn avoid_copying_the_body<F>(spawnfn: F) where F: FnOnce(Thunk<'static>) {
|
2014-11-25 08:52:10 -08:00
|
|
|
let (tx, rx) = channel::<uint>();
|
|
|
|
|
|
|
|
let x = box 1;
|
|
|
|
let x_in_parent = (&*x) as *const int as uint;
|
|
|
|
|
2014-12-14 00:05:32 -08:00
|
|
|
spawnfn(Thunk::new(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
let x_in_child = (&*x) as *const int as uint;
|
2014-12-23 11:53:35 -08:00
|
|
|
tx.send(x_in_child).unwrap();
|
2014-12-14 00:05:32 -08:00
|
|
|
}));
|
2014-11-25 08:52:10 -08:00
|
|
|
|
2014-12-23 11:53:35 -08:00
|
|
|
let x_in_child = rx.recv().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
assert_eq!(x_in_parent, x_in_child);
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_avoid_copying_the_body_spawn() {
|
2014-12-14 00:05:32 -08:00
|
|
|
avoid_copying_the_body(|v| {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move || v.invoke(()));
|
2014-12-14 00:05:32 -08:00
|
|
|
});
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_avoid_copying_the_body_thread_spawn() {
|
|
|
|
avoid_copying_the_body(|f| {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| {
|
2014-12-14 00:05:32 -08:00
|
|
|
f.invoke(());
|
2015-01-05 21:59:45 -08:00
|
|
|
});
|
2014-11-25 08:52:10 -08:00
|
|
|
})
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_avoid_copying_the_body_join() {
|
|
|
|
avoid_copying_the_body(|f| {
|
2015-02-17 15:10:25 -08:00
|
|
|
let _ = thread::spawn(move|| {
|
2014-12-14 00:05:32 -08:00
|
|
|
f.invoke(())
|
2014-11-25 08:52:10 -08:00
|
|
|
}).join();
|
|
|
|
})
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_child_doesnt_ref_parent() {
|
|
|
|
// If the child refcounts the parent task, this will stack overflow when
|
|
|
|
// climbing the task tree to dereference each ancestor. (See #1789)
|
|
|
|
// (well, it would if the constant were 8000+ - I lowered it to be more
|
|
|
|
// valgrind-friendly. try this at home, instead..!)
|
|
|
|
static GENERATIONS: uint = 16;
|
2015-02-17 23:48:32 +11:00
|
|
|
fn child_no(x: uint) -> Thunk<'static> {
|
2014-12-14 00:05:32 -08:00
|
|
|
return Thunk::new(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
if x < GENERATIONS {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move|| child_no(x+1).invoke(()));
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
2014-12-14 00:05:32 -08:00
|
|
|
});
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(|| child_no(0).invoke(()));
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_simple_newsched_spawn() {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::spawn(move || {});
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_try_panic_message_static_str() {
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
panic!("static string");
|
|
|
|
}).join() {
|
|
|
|
Err(e) => {
|
|
|
|
type T = &'static str;
|
|
|
|
assert!(e.is::<T>());
|
2015-01-20 15:45:07 -08:00
|
|
|
assert_eq!(*e.downcast::<T>().ok().unwrap(), "static string");
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
Ok(()) => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_try_panic_message_owned_str() {
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
panic!("owned string".to_string());
|
|
|
|
}).join() {
|
|
|
|
Err(e) => {
|
|
|
|
type T = String;
|
|
|
|
assert!(e.is::<T>());
|
2015-01-20 15:45:07 -08:00
|
|
|
assert_eq!(*e.downcast::<T>().ok().unwrap(), "owned string".to_string());
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
Ok(()) => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_try_panic_message_any() {
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
panic!(box 413u16 as Box<Any + Send>);
|
|
|
|
}).join() {
|
|
|
|
Err(e) => {
|
|
|
|
type T = Box<Any + Send>;
|
|
|
|
assert!(e.is::<T>());
|
2015-01-20 15:45:07 -08:00
|
|
|
let any = e.downcast::<T>().ok().unwrap();
|
2014-11-25 08:52:10 -08:00
|
|
|
assert!(any.is::<u16>());
|
2015-01-20 15:45:07 -08:00
|
|
|
assert_eq!(*any.downcast::<u16>().ok().unwrap(), 413u16);
|
2014-11-25 08:52:10 -08:00
|
|
|
}
|
|
|
|
Ok(()) => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_try_panic_message_unit_struct() {
|
|
|
|
struct Juju;
|
|
|
|
|
2015-02-17 15:10:25 -08:00
|
|
|
match thread::spawn(move|| {
|
2014-11-25 08:52:10 -08:00
|
|
|
panic!(Juju)
|
|
|
|
}).join() {
|
|
|
|
Err(ref e) if e.is::<Juju>() => {}
|
|
|
|
Err(_) | Ok(()) => panic!()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_stdout() {
|
|
|
|
let (tx, rx) = channel();
|
|
|
|
let mut reader = ChanReader::new(rx);
|
|
|
|
let stdout = ChanWriter::new(tx);
|
|
|
|
|
2015-01-05 21:59:45 -08:00
|
|
|
let r = Builder::new().stdout(box stdout as Box<Writer + Send>).scoped(move|| {
|
2014-12-14 00:05:32 -08:00
|
|
|
print!("Hello, world!");
|
|
|
|
}).join();
|
2014-11-25 08:52:10 -08:00
|
|
|
assert!(r.is_ok());
|
|
|
|
|
|
|
|
let output = reader.read_to_string().unwrap();
|
|
|
|
assert_eq!(output, "Hello, world!".to_string());
|
|
|
|
}
|
|
|
|
|
2015-01-30 13:44:13 -08:00
|
|
|
#[test]
|
|
|
|
fn test_park_timeout_unpark_before() {
|
|
|
|
for _ in 0..10 {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::current().unpark();
|
|
|
|
thread::park_timeout(Duration::seconds(10_000_000));
|
2015-01-30 13:44:13 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_park_timeout_unpark_not_called() {
|
|
|
|
for _ in 0..10 {
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::park_timeout(Duration::milliseconds(10));
|
2015-01-30 13:44:13 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#[test]
|
|
|
|
fn test_park_timeout_unpark_called_other_thread() {
|
|
|
|
use std::old_io;
|
|
|
|
|
|
|
|
for _ in 0..10 {
|
2015-02-17 15:10:25 -08:00
|
|
|
let th = thread::current();
|
2015-01-30 13:44:13 -08:00
|
|
|
|
2015-02-17 15:10:25 -08:00
|
|
|
let _guard = thread::spawn(move || {
|
2015-01-30 13:44:13 -08:00
|
|
|
old_io::timer::sleep(Duration::milliseconds(50));
|
|
|
|
th.unpark();
|
|
|
|
});
|
|
|
|
|
2015-02-17 15:10:25 -08:00
|
|
|
thread::park_timeout(Duration::seconds(10_000_000));
|
2015-01-30 13:44:13 -08:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2014-11-25 08:52:10 -08:00
|
|
|
// NOTE: the corresponding test for stderr is in run-pass/task-stderr, due
|
|
|
|
// to the test harness apparently interfering with stderr configuration.
|
|
|
|
}
|