diff options
Diffstat (limited to 'vendor/scopeguard')
| -rw-r--r-- | vendor/scopeguard/.cargo-checksum.json | 1 | ||||
| -rw-r--r-- | vendor/scopeguard/Cargo.lock | 7 | ||||
| -rw-r--r-- | vendor/scopeguard/Cargo.toml | 43 | ||||
| -rw-r--r-- | vendor/scopeguard/LICENSE-APACHE | 201 | ||||
| -rw-r--r-- | vendor/scopeguard/LICENSE-MIT | 25 | ||||
| -rw-r--r-- | vendor/scopeguard/README.md | 102 | ||||
| -rw-r--r-- | vendor/scopeguard/examples/readme.rs | 29 | ||||
| -rw-r--r-- | vendor/scopeguard/src/lib.rs | 595 |
8 files changed, 0 insertions, 1003 deletions
diff --git a/vendor/scopeguard/.cargo-checksum.json b/vendor/scopeguard/.cargo-checksum.json deleted file mode 100644 index 5afe735..0000000 --- a/vendor/scopeguard/.cargo-checksum.json +++ /dev/null @@ -1 +0,0 @@ -{"files":{"Cargo.lock":"684e99cc5938e7e51e1c5808214f9125ccfe66efa6ca5392303a7ee5337e1294","Cargo.toml":"68899251551903e2e1ba03c927f12e4c19fc8a15e8bd3756610f53f5ec075b48","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"fb77f0a9c53e473abe5103c8632ef9f0f2874d4fb3f17cb2d8c661aab9cee9d7","README.md":"68d5a7beebf814cffaaf6fe5758984fd06554b3bb5a49b2e13fc101522909b91","examples/readme.rs":"c6b1b458a130e091b1465040184759f1cc7d4e8de8d9cb893def0107238c2964","src/lib.rs":"3fb8bba1227724954c01cf98ec984bcf49ee74624faa74eb1bcea9018682751c"},"package":"94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"}
\ No newline at end of file diff --git a/vendor/scopeguard/Cargo.lock b/vendor/scopeguard/Cargo.lock deleted file mode 100644 index ebfce51..0000000 --- a/vendor/scopeguard/Cargo.lock +++ /dev/null @@ -1,7 +0,0 @@ -# This file is automatically @generated by Cargo. -# It is not intended for manual editing. -version = 3 - -[[package]] -name = "scopeguard" -version = "1.2.0" diff --git a/vendor/scopeguard/Cargo.toml b/vendor/scopeguard/Cargo.toml deleted file mode 100644 index acf5dce..0000000 --- a/vendor/scopeguard/Cargo.toml +++ /dev/null @@ -1,43 +0,0 @@ -# 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 are reading this file be aware that the original Cargo.toml -# will likely look very different (and much more reasonable). -# See Cargo.toml.orig for the original contents. - -[package] -name = "scopeguard" -version = "1.2.0" -authors = ["bluss"] -description = """ -A RAII scope guard that will run a given closure when it goes out of scope, -even if the code between panics (assuming unwinding panic). - -Defines the macros `defer!`, `defer_on_unwind!`, `defer_on_success!` as -shorthands for guards with one of the implemented strategies. -""" -documentation = "https://docs.rs/scopeguard/" -readme = "README.md" -keywords = [ - "scope-guard", - "defer", - "panic", - "unwind", -] -categories = [ - "rust-patterns", - "no-std", -] -license = "MIT OR Apache-2.0" -repository = "https://github.com/bluss/scopeguard" - -[package.metadata.release] -no-dev-version = true - -[features] -default = ["use_std"] -use_std = [] diff --git a/vendor/scopeguard/LICENSE-APACHE b/vendor/scopeguard/LICENSE-APACHE deleted file mode 100644 index 16fe87b..0000000 --- a/vendor/scopeguard/LICENSE-APACHE +++ /dev/null @@ -1,201 +0,0 @@ - Apache License - Version 2.0, January 2004 - http://www.apache.org/licenses/ - -TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION - -1. Definitions. - - "License" shall mean the terms and conditions for use, reproduction, - and distribution as defined by Sections 1 through 9 of this document. - - "Licensor" shall mean the copyright owner or entity authorized by - the copyright owner that is granting the License. - - "Legal Entity" shall mean the union of the acting entity and all - other entities that control, are controlled by, or are under common - control with that entity. For the purposes of this definition, - "control" means (i) the power, direct or indirect, to cause the - direction or management of such entity, whether by contract or - otherwise, or (ii) ownership of fifty percent (50%) or more of the - outstanding shares, or (iii) beneficial ownership of such entity. - - "You" (or "Your") shall mean an individual or Legal Entity - exercising permissions granted by this License. - - "Source" form shall mean the preferred form for making modifications, - including but not limited to software source code, documentation - source, and configuration files. - - "Object" form shall mean any form resulting from mechanical - transformation or translation of a Source form, including but - not limited to compiled object code, generated documentation, - and conversions to other media types. - - "Work" shall mean the work of authorship, whether in Source or - Object form, made available under the License, as indicated by a - copyright notice that is included in or attached to the work - (an example is provided in the Appendix below). - - "Derivative Works" shall mean any work, whether in Source or Object - form, that is based on (or derived from) the Work and for which the - editorial revisions, annotations, elaborations, or other modifications - represent, as a whole, an original work of authorship. For the purposes - of this License, Derivative Works shall not include works that remain - separable from, or merely link (or bind by name) to the interfaces of, - the Work and Derivative Works thereof. - - "Contribution" shall mean any work of authorship, including - the original version of the Work and any modifications or additions - to that Work or Derivative Works thereof, that is intentionally - submitted to Licensor for inclusion in the Work by the copyright owner - or by an individual or Legal Entity authorized to submit on behalf of - the copyright owner. For the purposes of this definition, "submitted" - means any form of electronic, verbal, or written communication sent - to the Licensor or its representatives, including but not limited to - communication on electronic mailing lists, source code control systems, - and issue tracking systems that are managed by, or on behalf of, the - Licensor for the purpose of discussing and improving the Work, but - excluding communication that is conspicuously marked or otherwise - designated in writing by the copyright owner as "Not a Contribution." - - "Contributor" shall mean Licensor and any individual or Legal Entity - on behalf of whom a Contribution has been received by Licensor and - subsequently incorporated within the Work. - -2. Grant of Copyright License. Subject to the terms and conditions of - this License, each Contributor hereby grants to You a perpetual, - worldwide, non-exclusive, no-charge, royalty-free, irrevocable - copyright license to reproduce, prepare Derivative Works of, - publicly display, publicly perform, sublicense, and distribute the - Work and such Derivative Works in Source or Object form. - -3. Grant of Patent License. Subject to the terms and conditions of - this License, each Contributor hereby grants to You a perpetual, - worldwide, non-exclusive, no-charge, royalty-free, irrevocable - (except as stated in this section) patent license to make, have made, - use, offer to sell, sell, import, and otherwise transfer the Work, - where such license applies only to those patent claims licensable - by such Contributor that are necessarily infringed by their - Contribution(s) alone or by combination of their Contribution(s) - with the Work to which such Contribution(s) was submitted. If You - institute patent litigation against any entity (including a - cross-claim or counterclaim in a lawsuit) alleging that the Work - or a Contribution incorporated within the Work constitutes direct - or contributory patent infringement, then any patent licenses - granted to You under this License for that Work shall terminate - as of the date such litigation is filed. - -4. Redistribution. You may reproduce and distribute copies of the - Work or Derivative Works thereof in any medium, with or without - modifications, and in Source or Object form, provided that You - meet the following conditions: - - (a) You must give any other recipients of the Work or - Derivative Works a copy of this License; and - - (b) You must cause any modified files to carry prominent notices - stating that You changed the files; and - - (c) You must retain, in the Source form of any Derivative Works - that You distribute, all copyright, patent, trademark, and - attribution notices from the Source form of the Work, - excluding those notices that do not pertain to any part of - the Derivative Works; and - - (d) If the Work includes a "NOTICE" text file as part of its - distribution, then any Derivative Works that You distribute must - include a readable copy of the attribution notices contained - within such NOTICE file, excluding those notices that do not - pertain to any part of the Derivative Works, in at least one - of the following places: within a NOTICE text file distributed - as part of the Derivative Works; within the Source form or - documentation, if provided along with the Derivative Works; or, - within a display generated by the Derivative Works, if and - wherever such third-party notices normally appear. The contents - of the NOTICE file are for informational purposes only and - do not modify the License. You may add Your own attribution - notices within Derivative Works that You distribute, alongside - or as an addendum to the NOTICE text from the Work, provided - that such additional attribution notices cannot be construed - as modifying the License. - - You may add Your own copyright statement to Your modifications and - may provide additional or different license terms and conditions - for use, reproduction, or distribution of Your modifications, or - for any such Derivative Works as a whole, provided Your use, - reproduction, and distribution of the Work otherwise complies with - the conditions stated in this License. - -5. Submission of Contributions. Unless You explicitly state otherwise, - any Contribution intentionally submitted for inclusion in the Work - by You to the Licensor shall be under the terms and conditions of - this License, without any additional terms or conditions. - Notwithstanding the above, nothing herein shall supersede or modify - the terms of any separate license agreement you may have executed - with Licensor regarding such Contributions. - -6. Trademarks. This License does not grant permission to use the trade - names, trademarks, service marks, or product names of the Licensor, - except as required for reasonable and customary use in describing the - origin of the Work and reproducing the content of the NOTICE file. - -7. Disclaimer of Warranty. Unless required by applicable law or - agreed to in writing, Licensor provides the Work (and each - Contributor provides its Contributions) on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or - implied, including, without limitation, any warranties or conditions - of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A - PARTICULAR PURPOSE. You are solely responsible for determining the - appropriateness of using or redistributing the Work and assume any - risks associated with Your exercise of permissions under this License. - -8. Limitation of Liability. In no event and under no legal theory, - whether in tort (including negligence), contract, or otherwise, - unless required by applicable law (such as deliberate and grossly - negligent acts) or agreed to in writing, shall any Contributor be - liable to You for damages, including any direct, indirect, special, - incidental, or consequential damages of any character arising as a - result of this License or out of the use or inability to use the - Work (including but not limited to damages for loss of goodwill, - work stoppage, computer failure or malfunction, or any and all - other commercial damages or losses), even if such Contributor - has been advised of the possibility of such damages. - -9. Accepting Warranty or Additional Liability. While redistributing - the Work or Derivative Works thereof, You may choose to offer, - and charge a fee for, acceptance of support, warranty, indemnity, - or other liability obligations and/or rights consistent with this - License. However, in accepting such obligations, You may act only - on Your own behalf and on Your sole responsibility, not on behalf - of any other Contributor, and only if You agree to indemnify, - defend, and hold each Contributor harmless for any liability - incurred by, or claims asserted against, such Contributor by reason - of your accepting any such warranty or additional liability. - -END OF TERMS AND CONDITIONS - -APPENDIX: How to apply the Apache License to your work. - - To apply the Apache License to your work, attach the following - boilerplate notice, with the fields enclosed by brackets "[]" - replaced with your own identifying information. (Don't include - the brackets!) The text should be enclosed in the appropriate - comment syntax for the file format. We also recommend that a - file or class name and description of purpose be included on the - same "printed page" as the copyright notice for easier - identification within third-party archives. - -Copyright [yyyy] [name of copyright owner] - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. diff --git a/vendor/scopeguard/LICENSE-MIT b/vendor/scopeguard/LICENSE-MIT deleted file mode 100644 index 8514471..0000000 --- a/vendor/scopeguard/LICENSE-MIT +++ /dev/null @@ -1,25 +0,0 @@ -Copyright (c) 2016-2019 Ulrik Sverdrup "bluss" and scopeguard developers - -Permission is hereby granted, free of charge, to any -person obtaining a copy of this software and associated -documentation files (the "Software"), to deal in the -Software without restriction, including without -limitation the rights to use, copy, modify, merge, -publish, distribute, sublicense, and/or sell copies of -the Software, and to permit persons to whom the Software -is furnished to do so, subject to the following -conditions: - -The above copyright notice and this permission notice -shall be included in all copies or substantial portions -of the Software. - -THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF -ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED -TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A -PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT -SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY -CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION -OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR -IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER -DEALINGS IN THE SOFTWARE. diff --git a/vendor/scopeguard/README.md b/vendor/scopeguard/README.md deleted file mode 100644 index 01fa68c..0000000 --- a/vendor/scopeguard/README.md +++ /dev/null @@ -1,102 +0,0 @@ -# scopeguard - -Rust crate for a convenient RAII scope guard that will run a given closure when -it goes out of scope, even if the code between panics (assuming unwinding panic). - -The `defer!` macro and `guard` are `no_std` compatible (require only `core`), -but the on unwinding / not on unwinding strategies require linking to `std`. -By default, the `use_std` crate feature is enabled. Disable the default features -for `no_std` support. - -Please read the [API documentation here](https://docs.rs/scopeguard/). - -Minimum supported Rust version: 1.20 - -[](https://github.com/bluss/scopeguard/actions/workflows/ci.yaml) -[](https://crates.io/crates/scopeguard) - -## How to use - -```rs -#[macro_use(defer)] -extern crate scopeguard; - -use scopeguard::guard; - -fn f() { - defer! { - println!("Called at return or panic"); - } - panic!(); -} - -use std::fs::File; -use std::io::Write; - -fn g() { - let f = File::create("newfile.txt").unwrap(); - let mut file = guard(f, |f| { - // write file at return or panic - let _ = f.sync_all(); - }); - // access the file through the scope guard itself - file.write_all(b"test me\n").unwrap(); -} -``` - -## Recent Changes - -- 1.2.0 - - - Use ManuallyDrop instead of mem::forget in into_inner. (by @willtunnels) - - Warn if the guard is not assigned to a variable and is dropped immediately - instead of at the scope's end. (by @sergey-v-galtsev) - -- 1.1.0 - - - Change macros (`defer!`, `defer_on_success!` and `defer_on_unwind!`) - to accept statements. (by @konsumlamm) - -- 1.0.0 - - - Change the closure type from `FnMut(&mut T)` to `FnOnce(T)`: - Passing the inner value by value instead of a mutable reference is a - breaking change, but allows the guard closure to consume it. (by @tormol) - - - Add `defer_on_success!`, `guard_on_success()` and `OnSuccess` - strategy, which triggers when scope is exited *without* panic. It's the - opposite to `defer_on_unwind!` / `guard_on_unwind()` / `OnUnwind`. - - - Add `ScopeGuard::into_inner()`, which "defuses" the guard and returns the - guarded value. (by @tormol) - - - Implement `Sync` for guards with non-`Sync` closures. - - - Require Rust 1.20 - -- 0.3.3 - - - Use `#[inline]` on a few more functions by @stjepang (#14) - - Add examples to crate documentation - -- 0.3.2 - - - Add crate categories - -- 0.3.1 - - - Add `defer_on_unwind!`, `Strategy` trait - - Rename `Guard` → `ScopeGuard` - - Add `ScopeGuard::with_strategy`. - - `ScopeGuard` now implements `Debug`. - - Require Rust 1.11 - -- 0.2.0 - - - Require Rust 1.6 - - Use `no_std` unconditionally - - No other changes - -- 0.1.2 - - - Add macro `defer!` diff --git a/vendor/scopeguard/examples/readme.rs b/vendor/scopeguard/examples/readme.rs deleted file mode 100644 index c4567e5..0000000 --- a/vendor/scopeguard/examples/readme.rs +++ /dev/null @@ -1,29 +0,0 @@ -#[macro_use(defer)] -extern crate scopeguard; - -use scopeguard::guard; - -fn f() { - defer! { - println!("Called at return or panic"); - } - panic!(); -} - -use std::fs::File; -use std::io::Write; - -fn g() { - let f = File::create("newfile.txt").unwrap(); - let mut file = guard(f, |f| { - // write file at return or panic - let _ = f.sync_all(); - }); - // access the file through the scope guard itself - file.write_all(b"test me\n").unwrap(); -} - -fn main() { - f(); - g(); -} diff --git a/vendor/scopeguard/src/lib.rs b/vendor/scopeguard/src/lib.rs deleted file mode 100644 index b5522c7..0000000 --- a/vendor/scopeguard/src/lib.rs +++ /dev/null @@ -1,595 +0,0 @@ -#![cfg_attr(not(any(test, feature = "use_std")), no_std)] -#![doc(html_root_url = "https://docs.rs/scopeguard/1/")] - -//! A scope guard will run a given closure when it goes out of scope, -//! even if the code between panics. -//! (as long as panic doesn't abort) -//! -//! # Examples -//! -//! ## Hello World -//! -//! This example creates a scope guard with an example function: -//! -//! ``` -//! extern crate scopeguard; -//! -//! fn f() { -//! let _guard = scopeguard::guard((), |_| { -//! println!("Hello Scope Exit!"); -//! }); -//! -//! // rest of the code here. -//! -//! // Here, at the end of `_guard`'s scope, the guard's closure is called. -//! // It is also called if we exit this scope through unwinding instead. -//! } -//! # fn main() { -//! # f(); -//! # } -//! ``` -//! -//! ## `defer!` -//! -//! Use the `defer` macro to run an operation at scope exit, -//! either regular scope exit or during unwinding from a panic. -//! -//! ``` -//! #[macro_use(defer)] extern crate scopeguard; -//! -//! use std::cell::Cell; -//! -//! fn main() { -//! // use a cell to observe drops during and after the scope guard is active -//! let drop_counter = Cell::new(0); -//! { -//! // Create a scope guard using `defer!` for the current scope -//! defer! { -//! drop_counter.set(1 + drop_counter.get()); -//! } -//! -//! // Do regular operations here in the meantime. -//! -//! // Just before scope exit: it hasn't run yet. -//! assert_eq!(drop_counter.get(), 0); -//! -//! // The following scope end is where the defer closure is called -//! } -//! assert_eq!(drop_counter.get(), 1); -//! } -//! ``` -//! -//! ## Scope Guard with Value -//! -//! If the scope guard closure needs to access an outer value that is also -//! mutated outside of the scope guard, then you may want to use the scope guard -//! with a value. The guard works like a smart pointer, so the inner value can -//! be accessed by reference or by mutable reference. -//! -//! ### 1. The guard owns a file -//! -//! In this example, the scope guard owns a file and ensures pending writes are -//! synced at scope exit. -//! -//! ``` -//! extern crate scopeguard; -//! -//! use std::fs::*; -//! use std::io::{self, Write}; -//! # // Mock file so that we don't actually write a file -//! # struct MockFile; -//! # impl MockFile { -//! # fn create(_s: &str) -> io::Result<Self> { Ok(MockFile) } -//! # fn write_all(&self, _b: &[u8]) -> io::Result<()> { Ok(()) } -//! # fn sync_all(&self) -> io::Result<()> { Ok(()) } -//! # } -//! # use self::MockFile as File; -//! -//! fn try_main() -> io::Result<()> { -//! let f = File::create("newfile.txt")?; -//! let mut file = scopeguard::guard(f, |f| { -//! // ensure we flush file at return or panic -//! let _ = f.sync_all(); -//! }); -//! // Access the file through the scope guard itself -//! file.write_all(b"test me\n").map(|_| ()) -//! } -//! -//! fn main() { -//! try_main().unwrap(); -//! } -//! -//! ``` -//! -//! ### 2. The guard restores an invariant on scope exit -//! -//! ``` -//! extern crate scopeguard; -//! -//! use std::mem::ManuallyDrop; -//! use std::ptr; -//! -//! // This function, just for this example, takes the first element -//! // and inserts it into the assumed sorted tail of the vector. -//! // -//! // For optimization purposes we temporarily violate an invariant of the -//! // Vec, that it owns all of its elements. -//! // -//! // The safe approach is to use swap, which means two writes to memory, -//! // the optimization is to use a “hole” which uses only one write of memory -//! // for each position it moves. -//! // -//! // We *must* use a scope guard to run this code safely. We -//! // are running arbitrary user code (comparison operators) that may panic. -//! // The scope guard ensures we restore the invariant after successful -//! // exit or during unwinding from panic. -//! fn insertion_sort_first<T>(v: &mut Vec<T>) -//! where T: PartialOrd -//! { -//! struct Hole<'a, T: 'a> { -//! v: &'a mut Vec<T>, -//! index: usize, -//! value: ManuallyDrop<T>, -//! } -//! -//! unsafe { -//! // Create a moved-from location in the vector, a “hole”. -//! let value = ptr::read(&v[0]); -//! let mut hole = Hole { v: v, index: 0, value: ManuallyDrop::new(value) }; -//! -//! // Use a scope guard with a value. -//! // At scope exit, plug the hole so that the vector is fully -//! // initialized again. -//! // The scope guard owns the hole, but we can access it through the guard. -//! let mut hole_guard = scopeguard::guard(hole, |hole| { -//! // plug the hole in the vector with the value that was // taken out -//! let index = hole.index; -//! ptr::copy_nonoverlapping(&*hole.value, &mut hole.v[index], 1); -//! }); -//! -//! // run algorithm that moves the hole in the vector here -//! // move the hole until it's in a sorted position -//! for i in 1..hole_guard.v.len() { -//! if *hole_guard.value >= hole_guard.v[i] { -//! // move the element back and the hole forward -//! let index = hole_guard.index; -//! hole_guard.v.swap(index, index + 1); -//! hole_guard.index += 1; -//! } else { -//! break; -//! } -//! } -//! -//! // When the scope exits here, the Vec becomes whole again! -//! } -//! } -//! -//! fn main() { -//! let string = String::from; -//! let mut data = vec![string("c"), string("a"), string("b"), string("d")]; -//! insertion_sort_first(&mut data); -//! assert_eq!(data, vec!["a", "b", "c", "d"]); -//! } -//! -//! ``` -//! -//! -//! # Crate Features -//! -//! - `use_std` -//! + Enabled by default. Enables the `OnUnwind` and `OnSuccess` strategies. -//! + Disable to use `no_std`. -//! -//! # Rust Version -//! -//! This version of the crate requires Rust 1.20 or later. -//! -//! The scopeguard 1.x release series will use a carefully considered version -//! upgrade policy, where in a later 1.x version, we will raise the minimum -//! required Rust version. - -#[cfg(not(any(test, feature = "use_std")))] -extern crate core as std; - -use std::fmt; -use std::marker::PhantomData; -use std::mem::ManuallyDrop; -use std::ops::{Deref, DerefMut}; -use std::ptr; - -/// Controls in which cases the associated code should be run -pub trait Strategy { - /// Return `true` if the guard’s associated code should run - /// (in the context where this method is called). - fn should_run() -> bool; -} - -/// Always run on scope exit. -/// -/// “Always” run: on regular exit from a scope or on unwinding from a panic. -/// Can not run on abort, process exit, and other catastrophic events where -/// destructors don’t run. -#[derive(Debug)] -pub enum Always {} - -/// Run on scope exit through unwinding. -/// -/// Requires crate feature `use_std`. -#[cfg(feature = "use_std")] -#[derive(Debug)] -pub enum OnUnwind {} - -/// Run on regular scope exit, when not unwinding. -/// -/// Requires crate feature `use_std`. -#[cfg(feature = "use_std")] -#[derive(Debug)] -pub enum OnSuccess {} - -impl Strategy for Always { - #[inline(always)] - fn should_run() -> bool { - true - } -} - -#[cfg(feature = "use_std")] -impl Strategy for OnUnwind { - #[inline] - fn should_run() -> bool { - std::thread::panicking() - } -} - -#[cfg(feature = "use_std")] -impl Strategy for OnSuccess { - #[inline] - fn should_run() -> bool { - !std::thread::panicking() - } -} - -/// Macro to create a `ScopeGuard` (always run). -/// -/// The macro takes statements, which are the body of a closure -/// that will run when the scope is exited. -#[macro_export] -macro_rules! defer { - ($($t:tt)*) => { - let _guard = $crate::guard((), |()| { $($t)* }); - }; -} - -/// Macro to create a `ScopeGuard` (run on successful scope exit). -/// -/// The macro takes statements, which are the body of a closure -/// that will run when the scope is exited. -/// -/// Requires crate feature `use_std`. -#[cfg(feature = "use_std")] -#[macro_export] -macro_rules! defer_on_success { - ($($t:tt)*) => { - let _guard = $crate::guard_on_success((), |()| { $($t)* }); - }; -} - -/// Macro to create a `ScopeGuard` (run on unwinding from panic). -/// -/// The macro takes statements, which are the body of a closure -/// that will run when the scope is exited. -/// -/// Requires crate feature `use_std`. -#[cfg(feature = "use_std")] -#[macro_export] -macro_rules! defer_on_unwind { - ($($t:tt)*) => { - let _guard = $crate::guard_on_unwind((), |()| { $($t)* }); - }; -} - -/// `ScopeGuard` is a scope guard that may own a protected value. -/// -/// If you place a guard in a local variable, the closure can -/// run regardless how you leave the scope — through regular return or panic -/// (except if panic or other code aborts; so as long as destructors run). -/// It is run only once. -/// -/// The `S` parameter for [`Strategy`](trait.Strategy.html) determines if -/// the closure actually runs. -/// -/// The guard's closure will be called with the held value in the destructor. -/// -/// The `ScopeGuard` implements `Deref` so that you can access the inner value. -pub struct ScopeGuard<T, F, S = Always> -where - F: FnOnce(T), - S: Strategy, -{ - value: ManuallyDrop<T>, - dropfn: ManuallyDrop<F>, - // fn(S) -> S is used, so that the S is not taken into account for auto traits. - strategy: PhantomData<fn(S) -> S>, -} - -impl<T, F, S> ScopeGuard<T, F, S> -where - F: FnOnce(T), - S: Strategy, -{ - /// Create a `ScopeGuard` that owns `v` (accessible through deref) and calls - /// `dropfn` when its destructor runs. - /// - /// The `Strategy` decides whether the scope guard's closure should run. - #[inline] - #[must_use] - pub fn with_strategy(v: T, dropfn: F) -> ScopeGuard<T, F, S> { - ScopeGuard { - value: ManuallyDrop::new(v), - dropfn: ManuallyDrop::new(dropfn), - strategy: PhantomData, - } - } - - /// “Defuse” the guard and extract the value without calling the closure. - /// - /// ``` - /// extern crate scopeguard; - /// - /// use scopeguard::{guard, ScopeGuard}; - /// - /// fn conditional() -> bool { true } - /// - /// fn main() { - /// let mut guard = guard(Vec::new(), |mut v| v.clear()); - /// guard.push(1); - /// - /// if conditional() { - /// // a condition maybe makes us decide to - /// // “defuse” the guard and get back its inner parts - /// let value = ScopeGuard::into_inner(guard); - /// } else { - /// // guard still exists in this branch - /// } - /// } - /// ``` - #[inline] - pub fn into_inner(guard: Self) -> T { - // Cannot move out of `Drop`-implementing types, - // so `ptr::read` the value and forget the guard. - let mut guard = ManuallyDrop::new(guard); - unsafe { - let value = ptr::read(&*guard.value); - // Drop the closure after `value` has been read, so that if the - // closure's `drop` function panics, unwinding still tries to drop - // `value`. - ManuallyDrop::drop(&mut guard.dropfn); - value - } - } -} - -/// Create a new `ScopeGuard` owning `v` and with deferred closure `dropfn`. -#[inline] -#[must_use] -pub fn guard<T, F>(v: T, dropfn: F) -> ScopeGuard<T, F, Always> -where - F: FnOnce(T), -{ - ScopeGuard::with_strategy(v, dropfn) -} - -/// Create a new `ScopeGuard` owning `v` and with deferred closure `dropfn`. -/// -/// Requires crate feature `use_std`. -#[cfg(feature = "use_std")] -#[inline] -#[must_use] -pub fn guard_on_success<T, F>(v: T, dropfn: F) -> ScopeGuard<T, F, OnSuccess> -where - F: FnOnce(T), -{ - ScopeGuard::with_strategy(v, dropfn) -} - -/// Create a new `ScopeGuard` owning `v` and with deferred closure `dropfn`. -/// -/// Requires crate feature `use_std`. -/// -/// ## Examples -/// -/// For performance reasons, or to emulate “only run guard on unwind” in -/// no-std environments, we can also use the default guard and simply manually -/// defuse it at the end of scope like the following example. (The performance -/// reason would be if the [`OnUnwind`]'s call to [std::thread::panicking()] is -/// an issue.) -/// -/// ``` -/// extern crate scopeguard; -/// -/// use scopeguard::ScopeGuard; -/// # fn main() { -/// { -/// let guard = scopeguard::guard((), |_| {}); -/// -/// // rest of the code here -/// -/// // we reached the end of scope without unwinding - defuse it -/// ScopeGuard::into_inner(guard); -/// } -/// # } -/// ``` -#[cfg(feature = "use_std")] -#[inline] -#[must_use] -pub fn guard_on_unwind<T, F>(v: T, dropfn: F) -> ScopeGuard<T, F, OnUnwind> -where - F: FnOnce(T), -{ - ScopeGuard::with_strategy(v, dropfn) -} - -// ScopeGuard can be Sync even if F isn't because the closure is -// not accessible from references. -// The guard does not store any instance of S, so it is also irrelevant. -unsafe impl<T, F, S> Sync for ScopeGuard<T, F, S> -where - T: Sync, - F: FnOnce(T), - S: Strategy, -{ -} - -impl<T, F, S> Deref for ScopeGuard<T, F, S> -where - F: FnOnce(T), - S: Strategy, -{ - type Target = T; - - fn deref(&self) -> &T { - &*self.value - } -} - -impl<T, F, S> DerefMut for ScopeGuard<T, F, S> -where - F: FnOnce(T), - S: Strategy, -{ - fn deref_mut(&mut self) -> &mut T { - &mut *self.value - } -} - -impl<T, F, S> Drop for ScopeGuard<T, F, S> -where - F: FnOnce(T), - S: Strategy, -{ - fn drop(&mut self) { - // This is OK because the fields are `ManuallyDrop`s - // which will not be dropped by the compiler. - let (value, dropfn) = unsafe { (ptr::read(&*self.value), ptr::read(&*self.dropfn)) }; - if S::should_run() { - dropfn(value); - } - } -} - -impl<T, F, S> fmt::Debug for ScopeGuard<T, F, S> -where - T: fmt::Debug, - F: FnOnce(T), - S: Strategy, -{ - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - f.debug_struct(stringify!(ScopeGuard)) - .field("value", &*self.value) - .finish() - } -} - -#[cfg(test)] -mod tests { - use super::*; - use std::cell::Cell; - use std::panic::catch_unwind; - use std::panic::AssertUnwindSafe; - - #[test] - fn test_defer() { - let drops = Cell::new(0); - defer!(drops.set(1000)); - assert_eq!(drops.get(), 0); - } - - #[cfg(feature = "use_std")] - #[test] - fn test_defer_success_1() { - let drops = Cell::new(0); - { - defer_on_success!(drops.set(1)); - assert_eq!(drops.get(), 0); - } - assert_eq!(drops.get(), 1); - } - - #[cfg(feature = "use_std")] - #[test] - fn test_defer_success_2() { - let drops = Cell::new(0); - let _ = catch_unwind(AssertUnwindSafe(|| { - defer_on_success!(drops.set(1)); - panic!("failure") - })); - assert_eq!(drops.get(), 0); - } - - #[cfg(feature = "use_std")] - #[test] - fn test_defer_unwind_1() { - let drops = Cell::new(0); - let _ = catch_unwind(AssertUnwindSafe(|| { - defer_on_unwind!(drops.set(1)); - assert_eq!(drops.get(), 0); - panic!("failure") - })); - assert_eq!(drops.get(), 1); - } - - #[cfg(feature = "use_std")] - #[test] - fn test_defer_unwind_2() { - let drops = Cell::new(0); - { - defer_on_unwind!(drops.set(1)); - } - assert_eq!(drops.get(), 0); - } - - #[test] - fn test_only_dropped_by_closure_when_run() { - let value_drops = Cell::new(0); - let value = guard((), |()| value_drops.set(1 + value_drops.get())); - let closure_drops = Cell::new(0); - let guard = guard(value, |_| closure_drops.set(1 + closure_drops.get())); - assert_eq!(value_drops.get(), 0); - assert_eq!(closure_drops.get(), 0); - drop(guard); - assert_eq!(value_drops.get(), 1); - assert_eq!(closure_drops.get(), 1); - } - - #[cfg(feature = "use_std")] - #[test] - fn test_dropped_once_when_not_run() { - let value_drops = Cell::new(0); - let value = guard((), |()| value_drops.set(1 + value_drops.get())); - let captured_drops = Cell::new(0); - let captured = guard((), |()| captured_drops.set(1 + captured_drops.get())); - let closure_drops = Cell::new(0); - let guard = guard_on_unwind(value, |value| { - drop(value); - drop(captured); - closure_drops.set(1 + closure_drops.get()) - }); - assert_eq!(value_drops.get(), 0); - assert_eq!(captured_drops.get(), 0); - assert_eq!(closure_drops.get(), 0); - drop(guard); - assert_eq!(value_drops.get(), 1); - assert_eq!(captured_drops.get(), 1); - assert_eq!(closure_drops.get(), 0); - } - - #[test] - fn test_into_inner() { - let dropped = Cell::new(false); - let value = guard(42, |_| dropped.set(true)); - let guard = guard(value, |_| dropped.set(true)); - let inner = ScopeGuard::into_inner(guard); - assert_eq!(dropped.get(), false); - assert_eq!(*inner, 42); - } -} |