diff options
Diffstat (limited to 'third_party/rust/runloop')
| -rw-r--r-- | third_party/rust/runloop/.cargo-checksum.json | 1 | ||||
| -rw-r--r-- | third_party/rust/runloop/Cargo.toml | 22 | ||||
| -rw-r--r-- | third_party/rust/runloop/LICENSE | 374 | ||||
| -rw-r--r-- | third_party/rust/runloop/README.md | 88 | ||||
| -rw-r--r-- | third_party/rust/runloop/rustfmt.toml | 2 | ||||
| -rw-r--r-- | third_party/rust/runloop/src/lib.rs | 168 |
6 files changed, 655 insertions, 0 deletions
diff --git a/third_party/rust/runloop/.cargo-checksum.json b/third_party/rust/runloop/.cargo-checksum.json new file mode 100644 index 0000000000..fd50999c06 --- /dev/null +++ b/third_party/rust/runloop/.cargo-checksum.json @@ -0,0 +1 @@ +{"files":{"Cargo.toml":"6148ea66fe5c0f49d36f01cc88b7aaf90a058ffb406402f0c9e8d790b32a509d","LICENSE":"b946744aeda89b467929585fe8eeb5461847695220c1b168fb375d8abd4ea3d0","README.md":"466aa6f249e465158175bd05567c1c9b996c3a57e22666ef78273e2a2f5a3f02","rustfmt.toml":"de4e1daab481c1572805aed3e51e72c5dc1b3e5af757bc675e1717b251c6e922","src/lib.rs":"e904c1c9d0fbc6dcf9749346f9ee612747e9755b33f60d57689249594d6b0750"},"package":"5d79b4b604167921892e84afbbaad9d5ad74e091bf6c511d9dbfb0593f09fabd"}
\ No newline at end of file diff --git a/third_party/rust/runloop/Cargo.toml b/third_party/rust/runloop/Cargo.toml new file mode 100644 index 0000000000..3746a73a5d --- /dev/null +++ b/third_party/rust/runloop/Cargo.toml @@ -0,0 +1,22 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g. crates.io) dependencies +# +# If you believe there's an error in this file please file an +# issue against the rust-lang/cargo repository. If you're +# editing this file be aware that the upstream Cargo.toml +# will likely look very different (and much more reasonable) + +[package] +name = "runloop" +version = "0.1.0" +authors = ["Tim Taubert <tim@timtaubert.de>"] +description = "Cancelable non-blocking polling threads (with optional timeouts)." +homepage = "https://github.com/ttaubert/rust-runloop/" +readme = "README.md" +keywords = ["runloop", "threads"] +license = "MPL-2.0" +repository = "https://github.com/ttaubert/rust-runloop/" diff --git a/third_party/rust/runloop/LICENSE b/third_party/rust/runloop/LICENSE new file mode 100644 index 0000000000..398385c9fb --- /dev/null +++ b/third_party/rust/runloop/LICENSE @@ -0,0 +1,374 @@ + Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" +means each individual or legal entity that creates, contributes to +the creation of, or owns Covered Software. + +1.2. "Contributor Version" +means the combination of the Contributions of others (if any) used +by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" +means Covered Software of a particular Contributor. + +1.4. "Covered Software" +means Source Code Form to which the initial Contributor has attached +the notice in Exhibit A, the Executable Form of such Source Code +Form, and Modifications of such Source Code Form, in each case +including portions thereof. + +1.5. "Incompatible With Secondary Licenses" +means + +(a) that the initial Contributor has attached the notice described +in Exhibit B to the Covered Software; or + +(b) that the Covered Software was made available under the terms of +version 1.1 or earlier of the License, but not also under the +terms of a Secondary License. + +1.6. "Executable Form" +means any form of the work other than Source Code Form. + +1.7. "Larger Work" +means a work that combines Covered Software with other material, in +a separate file or files, that is not Covered Software. + +1.8. "License" +means this document. + +1.9. "Licensable" +means having the right to grant, to the maximum extent possible, +whether at the time of the initial grant or subsequently, any and +all of the rights conveyed by this License. + +1.10. "Modifications" +means any of the following: + +(a) any file in Source Code Form that results from an addition to, +deletion from, or modification of the contents of Covered +Software; or + +(b) any new file in Source Code Form that contains any Covered +Software. + +1.11. "Patent Claims" of a Contributor +means any patent claim(s), including without limitation, method, +process, and apparatus claims, in any patent Licensable by such +Contributor that would be infringed, but for the grant of the +License, by the making, using, selling, offering for sale, having +made, import, or transfer of either its Contributions or its +Contributor Version. + +1.12. "Secondary License" +means either the GNU General Public License, Version 2.0, the GNU +Lesser General Public License, Version 2.1, the GNU Affero General +Public License, Version 3.0, or any later versions of those +licenses. + +1.13. "Source Code Form" +means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") +means an individual or a legal entity exercising rights under this +License. For legal entities, "You" includes any entity that +controls, is controlled by, or is under common control with You. For +purposes of this definition, "control" means (a) the power, direct +or indirect, to cause the direction or management of such entity, +whether by contract or otherwise, or (b) ownership of more than +fifty percent (50%) of the outstanding shares or beneficial +ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) +Licensable by such Contributor to use, reproduce, make available, +modify, display, perform, distribute, and otherwise exploit its +Contributions, either on an unmodified basis, with Modifications, or +as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer +for sale, have made, import, and otherwise transfer either its +Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; +or + +(b) for infringements caused by: (i) Your and any other third party's +modifications of Covered Software, or (ii) the combination of its +Contributions with other software (except as part of its Contributor +Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of +its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code +Form, as described in Section 3.1, and You must inform recipients of +the Executable Form how they can obtain a copy of such Source Code +Form by reasonable means in a timely manner, at a charge no more +than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this +License, or sublicense it under different terms, provided that the +license for the Executable Form does not attempt to limit or alter +the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + +This Source Code Form is subject to the terms of the Mozilla Public +License, v. 2.0. If a copy of the MPL was not distributed with this +file, You can obtain one at http://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + +This Source Code Form is "Incompatible With Secondary Licenses", as +defined by the Mozilla Public License, v. 2.0. + diff --git a/third_party/rust/runloop/README.md b/third_party/rust/runloop/README.md new file mode 100644 index 0000000000..8b9508b93b --- /dev/null +++ b/third_party/rust/runloop/README.md @@ -0,0 +1,88 @@ +# runloop [](https://crates.io/crates/runloop) [](https://travis-ci.org/ttaubert/rust-runloop) [](LICENSE) + +This crate provides a cancelable `RunLoop` to simplify writing non-blocking +polling threads. + +## Usage + +The closure passed to `RunLoop::new()` or `RunLoop::new_with_timeout()` will be +called once and is executed in the newly spawned thread. It should periodically +check, via the given callback argument named `alive` in the below examples, +whether the runloop was requested to terminate. + +`RunLoop::alive()` allows the owning thread to check whether the runloop is +still alive. This can be useful for debugging (e.g. assertions) or early +returns on failure in the passed closure. + +`RunLoop::cancel()` will request the runloop to terminate. If the runloop is +still active it will join the thread and block. If the runloop already +terminated on its own this will be a no-op. + +### Example: An endless runloop + +A runloop does not have to terminate on its own, it can wait until the +`cancel()` method is called. + +```rust +// This runloop runs until we stop it. +let rloop = RunLoop::new(|alive| { + while alive() { /* endless loop */ } +})?; + +// Loop a few times. +thread::sleep_ms(500); +assert!(rloop.alive()); + +// This will cause `alive()` to return false +// and block until the thread was joined. +rloop.cancel(); +``` + +### Example: A runloop with a timeout + +Creating a runloop via `new_with_timeout()` ensures that `alive()` returns +`false` after the given duration. + +```rust +// This runloop will time out after 10ms. +let rloop = RunLoop::new_with_timeout(|alive| { + while alive() { /* endless loop */ } +}, 10)?; + +// Wait for the timeout. +while rloop.alive() { /* loop */ } + +// This won't block anymore, it's a no-op. +// The runloop has already terminated. +rloop.cancel(); +``` + +### Example: A runloop with channels + +As a runloop will run the given closure in a newly spawned thread it requires +channels and similar utilities to communicate back to the owning thread. + +```rust +let (tx, rx) = channel(); + +// This runloop will send a lot of numbers. +let rloop = RunLoop::new(move |alive| { + let mut counter = 0u64; + while alive() { + tx.send(counter).unwrap(); + counter += 1; + } +})?; + +// Wait until we receive a specific number. +while rx.recv().unwrap() < 50 { /* loop */ } + +// We've seen enough. +rloop.cancel(); +``` + +## License + +`runloop` is distributed under the terms of the Mozilla Public License, v. 2.0. + +See [LICENSE](LICENSE) for details. diff --git a/third_party/rust/runloop/rustfmt.toml b/third_party/rust/runloop/rustfmt.toml new file mode 100644 index 0000000000..ed37b0c63a --- /dev/null +++ b/third_party/rust/runloop/rustfmt.toml @@ -0,0 +1,2 @@ +comment_width = 200 +wrap_comments = true diff --git a/third_party/rust/runloop/src/lib.rs b/third_party/rust/runloop/src/lib.rs new file mode 100644 index 0000000000..d705e605d0 --- /dev/null +++ b/third_party/rust/runloop/src/lib.rs @@ -0,0 +1,168 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +use std::io; +use std::sync::{Arc, Mutex, Weak}; +use std::sync::atomic::{AtomicBool, Ordering}; +use std::thread::{Builder, JoinHandle}; +use std::time::{Duration, Instant}; + +struct Canary { + alive: AtomicBool, + thread: Mutex<Option<JoinHandle<()>>>, +} + +impl Canary { + fn new() -> Self { + Self { + alive: AtomicBool::new(true), + thread: Mutex::new(None), + } + } +} + +pub struct RunLoop { + flag: Weak<Canary>, +} + +impl RunLoop { + pub fn new<F, T>(fun: F) -> io::Result<Self> + where + F: FnOnce(&Fn() -> bool) -> T, + F: Send + 'static, + { + Self::new_with_timeout(fun, 0 /* no timeout */) + } + + pub fn new_with_timeout<F, T>(fun: F, timeout_ms: u64) -> io::Result<Self> + where + F: FnOnce(&Fn() -> bool) -> T, + F: Send + 'static, + { + let flag = Arc::new(Canary::new()); + let flag_ = flag.clone(); + + // Spawn the run loop thread. + let thread = Builder::new().spawn(move || { + let timeout = Duration::from_millis(timeout_ms); + let start = Instant::now(); + + // A callback to determine whether the thread should terminate. + let still_alive = || { + // `flag.alive` will be false after cancel() was called. + flag.alive.load(Ordering::Relaxed) && + // If a timeout was provided, we'll check that too. + (timeout_ms == 0 || start.elapsed() < timeout) + }; + + // Ignore return values. + let _ = fun(&still_alive); + })?; + + // We really should never fail to lock here. + let mut guard = (*flag_).thread.lock().map_err(|_| { + io::Error::new(io::ErrorKind::Other, "failed to lock") + })?; + + // Store the thread handle so we can join later. + *guard = Some(thread); + + Ok(Self { flag: Arc::downgrade(&flag_) }) + } + + // Cancels the run loop and waits for the thread to terminate. + // This is a potentially BLOCKING operation. + pub fn cancel(&self) { + // If the thread still exists... + if let Some(flag) = self.flag.upgrade() { + // ...let the run loop terminate. + flag.alive.store(false, Ordering::Relaxed); + + // Locking should never fail here either. + if let Ok(mut guard) = flag.thread.lock() { + // This really can't fail. + if let Some(handle) = (*guard).take() { + // This might fail, ignore. + let _ = handle.join(); + } + } + } + } + + // Tells whether the runloop is alive. + pub fn alive(&self) -> bool { + // If the thread still exists... + if let Some(flag) = self.flag.upgrade() { + flag.alive.load(Ordering::Relaxed) + } else { + false + } + } +} + +#[cfg(test)] +mod tests { + use std::sync::{Arc, Barrier}; + use std::sync::mpsc::channel; + + use super::RunLoop; + + #[test] + fn test_empty() { + // Create a runloop that exits right away. + let rloop = RunLoop::new(|_| {}).unwrap(); + while rloop.alive() { /* wait */ } + rloop.cancel(); // noop + } + + #[test] + fn test_cancel_early() { + // Create a runloop and cancel it before the thread spawns. + RunLoop::new(|alive| assert!(!alive())).unwrap().cancel(); + } + + #[test] + fn test_cancel_endless_loop() { + let barrier = Arc::new(Barrier::new(2)); + let b = barrier.clone(); + + // Create a runloop that never exits. + let rloop = RunLoop::new(move |alive| { + b.wait(); + while alive() { /* loop */ } + }).unwrap(); + + barrier.wait(); + assert!(rloop.alive()); + rloop.cancel(); + assert!(!rloop.alive()); + } + + #[test] + fn test_timeout() { + // Create a runloop that never exits, but times out after 1ms. + let rloop = RunLoop::new_with_timeout(|alive| while alive() {}, 1).unwrap(); + + while rloop.alive() { /* wait */ } + assert!(!rloop.alive()); + rloop.cancel(); // noop + } + + #[test] + fn test_channel() { + let (tx, rx) = channel(); + + // A runloop that sends data via a channel. + let rloop = RunLoop::new(move |alive| while alive() { + tx.send(0u8).unwrap(); + }).unwrap(); + + // Wait until the data arrives. + assert_eq!(rx.recv().unwrap(), 0u8); + + assert!(rloop.alive()); + rloop.cancel(); + assert!(!rloop.alive()); + } +} |