memmap2-0.3.1/.cargo_vcs_info.json0000644000000001120000000000000123640ustar { "git": { "sha1": "27ece7685bfc4fe9909c396a651dc52306393a22" } } memmap2-0.3.1/.github/workflows/main.yml000064400000000000000000000044670000000000000162170ustar 00000000000000name: Rust on: [push, pull_request] env: CARGO_TERM_COLOR: always jobs: check: runs-on: ubuntu-20.04 steps: - name: Checkout uses: actions/checkout@v2 - name: Install toolchain uses: actions-rs/toolchain@v1 with: toolchain: stable profile: minimal target: x86_64-pc-windows-gnu - name: Run checks env: CLIPPY_OPTS: --all-targets -- --allow clippy::len_without_is_empty --allow clippy::missing_safety_doc run: | cargo fmt -- --check cargo clippy $CLIPPY_OPTS cargo clippy --target x86_64-pc-windows-gnu $CLIPPY_OPTS test-win: runs-on: windows-2019 strategy: matrix: target: - i686-pc-windows-gnu - i686-pc-windows-msvc - x86_64-pc-windows-gnu - x86_64-pc-windows-msvc steps: - name: Checkout uses: actions/checkout@v2 - name: Set default target run: rustup default stable-${{ matrix.target }} - name: Run tests run: cargo test test-macos-catalina: runs-on: macos-10.15 steps: - name: Checkout uses: actions/checkout@v2 - name: Run tests run: cargo test test-linux: runs-on: ubuntu-20.04 strategy: matrix: target: - i686-unknown-linux-gnu - x86_64-unknown-linux-gnu steps: - name: Checkout uses: actions/checkout@v2 - name: Set default target run: rustup default stable-${{ matrix.target }} - name: Install multilib if: ${{ matrix.target == 'i686-unknown-linux-gnu' }} run: sudo apt install gcc-multilib - name: Run tests run: cargo test check-stub: runs-on: ubuntu-20.04 steps: - name: Checkout uses: actions/checkout@v2 - name: Install toolchain uses: actions-rs/toolchain@v1 with: toolchain: stable profile: minimal target: wasm32-unknown-unknown override: true - name: Run check run: cargo check --target wasm32-unknown-unknown test-msrv: runs-on: ubuntu-20.04 steps: - name: Checkout uses: actions/checkout@v2 - name: Install toolchain uses: actions-rs/toolchain@v1 with: toolchain: 1.32.0 profile: minimal override: true - name: Run tests run: cargo test memmap2-0.3.1/.gitignore000064400000000000000000000000220000000000000131220ustar 00000000000000target Cargo.lock memmap2-0.3.1/CHANGELOG.md000064400000000000000000000041670000000000000127610ustar 00000000000000# Change Log All notable changes to this project will be documented in this file. The format is based on [Keep a Changelog](http://keepachangelog.com/) and this project adheres to [Semantic Versioning](http://semver.org/). ## [Unreleased] ## [0.3.1] - 2021-08-15 ### Fixed - Integer overflow during file length calculation on 32bit targets. - Stub implementation. [@Mrmaxmeier](https://github.com/Mrmaxmeier) ## [0.3.0] - 2021-06-10 ### Changed - `MmapOptions` allows mapping using Unix descriptors and not only `std::fs::File` now. [@mripard](https://github.com/mripard) ## [0.2.3] - 2021-05-24 ### Added - Allow compilation on unsupported platforms. The code will panic on access just like in `std`. [@jcaesar](https://github.com/jcaesar) ## [0.2.2] - 2021-04-03 ### Added - `MmapOptions::populate`. [@adamreichold](https://github.com/adamreichold) ### Fixed - Fix alignment computation for `flush_async` to match `flush`. [@adamreichold](https://github.com/adamreichold) ## [0.2.1] - 2021-02-08 ### Added - `MmapOptions::map_raw` and `MmapRaw`. [@diwic](https://github.com/diwic) ## [0.2.0] - 2020-12-19 ### Changed - MSRV is 1.31 now (edition 2018). - Make anonymous memory maps private by default on unix. [@CensoredUsername](https://github.com/CensoredUsername) - Add `map_copy_read_only`. [@zserik](https://github.com/zserik) ## 0.1.0 - 2020-01-18 ### Added - Fork [memmap-rs](https://github.com/danburkert/memmap-rs). ### Changed - Use `LICENSE-APACHE` instead of `README.md` for some tests since it's immutable. ### Removed - `winapi` dependency. [memmap-rs/pull/89](https://github.com/danburkert/memmap-rs/pull/89) [Unreleased]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.3.1...HEAD [0.3.1]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.3.0...v0.3.1 [0.3.0]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.2.3...v0.3.0 [0.2.3]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.2.2...v0.2.3 [0.2.2]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.2.1...v0.2.2 [0.2.1]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.2.0...v0.2.1 [0.2.0]: https://github.com/RazrFalcon/memmap2-rs/compare/v0.1.0...v0.2.0 memmap2-0.3.1/Cargo.lock0000644000000051540000000000000103520ustar # This file is automatically @generated by Cargo. # It is not intended for manual editing. version = 3 [[package]] name = "fuchsia-cprng" version = "0.1.1" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba" [[package]] name = "libc" version = "0.2.99" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "a7f823d141fe0a24df1e23b4af4e3c7ba9e5966ec514ea068c93024aa7deb765" [[package]] name = "memmap2" version = "0.3.1" dependencies = [ "libc", "tempdir", ] [[package]] name = "rand" version = "0.4.6" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "552840b97013b1a26992c11eac34bdd778e464601a4c2054b5f0bff7c6761293" dependencies = [ "fuchsia-cprng", "libc", "rand_core 0.3.1", "rdrand", "winapi", ] [[package]] name = "rand_core" version = "0.3.1" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b" dependencies = [ "rand_core 0.4.2", ] [[package]] name = "rand_core" version = "0.4.2" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc" [[package]] name = "rdrand" version = "0.4.0" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2" dependencies = [ "rand_core 0.3.1", ] [[package]] name = "remove_dir_all" version = "0.5.3" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "3acd125665422973a33ac9d3dd2df85edad0f4ae9b00dafb1a05e43a9f5ef8e7" dependencies = [ "winapi", ] [[package]] name = "tempdir" version = "0.3.7" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "15f2b5fb00ccdf689e0149d1b1b3c03fead81c2b37735d812fa8bddbbf41b6d8" dependencies = [ "rand", "remove_dir_all", ] [[package]] name = "winapi" version = "0.3.9" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419" dependencies = [ "winapi-i686-pc-windows-gnu", "winapi-x86_64-pc-windows-gnu", ] [[package]] name = "winapi-i686-pc-windows-gnu" version = "0.4.0" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6" [[package]] name = "winapi-x86_64-pc-windows-gnu" version = "0.4.0" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f" memmap2-0.3.1/Cargo.toml0000644000000017660000000000000104020ustar # 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] edition = "2018" name = "memmap2" version = "0.3.1" authors = ["Dan Burkert ", "Yevhenii Reizner "] description = "Cross-platform Rust API for memory-mapped file IO" documentation = "https://docs.rs/memmap2" keywords = ["mmap", "memory-map", "io", "file"] license = "MIT/Apache-2.0" repository = "https://github.com/RazrFalcon/memmap2-rs" [dev-dependencies.tempdir] version = "0.3" [target."cfg(unix)".dependencies.libc] version = "0.2" memmap2-0.3.1/Cargo.toml.orig000064400000000000000000000007330000000000000140320ustar 00000000000000[package] name = "memmap2" version = "0.3.1" authors = ["Dan Burkert ", "Yevhenii Reizner "] license = "MIT/Apache-2.0" repository = "https://github.com/RazrFalcon/memmap2-rs" documentation = "https://docs.rs/memmap2" description = "Cross-platform Rust API for memory-mapped file IO" keywords = ["mmap", "memory-map", "io", "file"] edition = "2018" [target.'cfg(unix)'.dependencies] libc = "0.2" [dev-dependencies] tempdir = "0.3" memmap2-0.3.1/LICENSE-APACHE000064400000000000000000000251230000000000000130670ustar 00000000000000 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 [2015] [Dan Burkert] 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. memmap2-0.3.1/LICENSE-MIT000064400000000000000000000021030000000000000125700ustar 00000000000000Copyright (c) 2020 Yevhenii Reizner Copyright (c) 2015 Dan Burkert 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. memmap2-0.3.1/README.md000064400000000000000000000022070000000000000124200ustar 00000000000000# memmap2 ![Build Status](https://github.com/RazrFalcon/memmap2-rs/workflows/Rust/badge.svg) [![Crates.io](https://img.shields.io/crates/v/memmap2.svg)](https://crates.io/crates/memmap2) [![Documentation](https://docs.rs/memmap2/badge.svg)](https://docs.rs/memmap2) [![Rust 1.31+](https://img.shields.io/badge/rust-1.31+-orange.svg)](https://www.rust-lang.org) A Rust library for cross-platform memory mapped IO. This is a **fork** of the [memmap-rs](https://github.com/danburkert/memmap-rs) crate. ## Features - [x] file-backed memory maps - [x] anonymous memory maps - [x] synchronous and asynchronous flushing - [x] copy-on-write memory maps - [x] read-only memory maps - [x] stack support (`MAP_STACK` on unix) - [x] executable memory maps - [ ] huge page support A list of supported/tested targets can be found in [Actions](https://github.com/RazrFalcon/memmap2-rs/actions). ## License `memmap2` is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0). See [LICENSE-APACHE](LICENSE-APACHE), [LICENSE-MIT](LICENSE-MIT) for details. Copyright (c) 2020 Yevhenii Reizner Copyright (c) 2015 Dan Burkert memmap2-0.3.1/examples/cat.rs000064400000000000000000000011060000000000000140710ustar 00000000000000extern crate memmap2; use std::env; use std::fs::File; use std::io::{self, Write}; use memmap2::Mmap; /// Output a file's contents to stdout. The file path must be provided as the first process /// argument. fn main() { let path = env::args() .nth(1) .expect("supply a single path as the program argument"); let file = File::open(path).expect("failed to open the file"); let mmap = unsafe { Mmap::map(&file).expect("failed to map the file") }; io::stdout() .write_all(&mmap[..]) .expect("failed to output the file contents"); } memmap2-0.3.1/src/lib.rs000064400000000000000000001240420000000000000130460ustar 00000000000000//! A cross-platform Rust API for memory mapped buffers. #![doc(html_root_url = "https://docs.rs/memmap2/0.3.1")] #[cfg(windows)] mod windows; #[cfg(windows)] use crate::windows::file_len; #[cfg(windows)] use crate::windows::MmapInner; #[cfg(unix)] mod unix; #[cfg(unix)] use crate::unix::file_len; #[cfg(unix)] use crate::unix::MmapInner; #[cfg(not(any(unix, windows)))] mod stub; #[cfg(not(any(unix, windows)))] use crate::stub::file_len; #[cfg(not(any(unix, windows)))] use crate::stub::MmapInner; use std::fmt; use std::fs::File; use std::io::{Error, ErrorKind, Result}; use std::ops::{Deref, DerefMut}; #[cfg(unix)] use std::os::unix::io::AsRawFd; use std::slice; use std::usize; #[cfg(windows)] pub struct MmapRawDescriptor<'a>(&'a File); #[cfg(unix)] pub struct MmapRawDescriptor(std::os::unix::io::RawFd); #[cfg(not(any(unix, windows)))] pub struct MmapRawDescriptor<'a>(&'a File); pub trait MmapAsRawDesc { fn as_raw_desc(&self) -> MmapRawDescriptor; } #[cfg(windows)] impl MmapAsRawDesc for &File { fn as_raw_desc(&self) -> MmapRawDescriptor { MmapRawDescriptor(self) } } #[cfg(unix)] impl MmapAsRawDesc for &File { fn as_raw_desc(&self) -> MmapRawDescriptor { MmapRawDescriptor(self.as_raw_fd()) } } #[cfg(unix)] impl MmapAsRawDesc for std::os::unix::io::RawFd { fn as_raw_desc(&self) -> MmapRawDescriptor { MmapRawDescriptor(*self) } } #[cfg(not(any(unix, windows)))] impl MmapAsRawDesc for &File { fn as_raw_desc(&self) -> MmapRawDescriptor { MmapRawDescriptor(self) } } /// A memory map builder, providing advanced options and flags for specifying memory map behavior. /// /// `MmapOptions` can be used to create an anonymous memory map using [`map_anon()`], or a /// file-backed memory map using one of [`map()`], [`map_mut()`], [`map_exec()`], /// [`map_copy()`], or [`map_copy_read_only()`]. /// /// ## Safety /// /// All file-backed memory map constructors are marked `unsafe` because of the potential for /// *Undefined Behavior* (UB) using the map if the underlying file is subsequently modified, in or /// out of process. Applications must consider the risk and take appropriate precautions when /// using file-backed maps. Solutions such as file permissions, locks or process-private (e.g. /// unlinked) files exist but are platform specific and limited. /// /// [`map_anon()`]: MmapOptions::map_anon() /// [`map()`]: MmapOptions::map() /// [`map_mut()`]: MmapOptions::map_mut() /// [`map_exec()`]: MmapOptions::map_exec() /// [`map_copy()`]: MmapOptions::map_copy() /// [`map_copy_read_only()`]: MmapOptions::map_copy_read_only() #[derive(Clone, Debug, Default)] pub struct MmapOptions { offset: u64, len: Option, stack: bool, populate: bool, } impl MmapOptions { /// Creates a new set of options for configuring and creating a memory map. /// /// # Example /// /// ``` /// use memmap2::{MmapMut, MmapOptions}; /// # use std::io::Result; /// /// # fn main() -> Result<()> { /// // Create a new memory map builder. /// let mut mmap_options = MmapOptions::new(); /// /// // Configure the memory map builder using option setters, then create /// // a memory map using one of `mmap_options.map_anon`, `mmap_options.map`, /// // `mmap_options.map_mut`, `mmap_options.map_exec`, or `mmap_options.map_copy`: /// let mut mmap: MmapMut = mmap_options.len(36).map_anon()?; /// /// // Use the memory map: /// mmap.copy_from_slice(b"...data to copy to the memory map..."); /// # Ok(()) /// # } /// ``` pub fn new() -> MmapOptions { MmapOptions::default() } /// Configures the memory map to start at byte `offset` from the beginning of the file. /// /// This option has no effect on anonymous memory maps. /// /// By default, the offset is 0. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// /// # fn main() -> std::io::Result<()> { /// let mmap = unsafe { /// MmapOptions::new() /// .offset(30) /// .map(&File::open("LICENSE-APACHE")?)? /// }; /// assert_eq!(&b"Apache License"[..], /// &mmap[..14]); /// # Ok(()) /// # } /// ``` pub fn offset(&mut self, offset: u64) -> &mut Self { self.offset = offset; self } /// Configures the created memory mapped buffer to be `len` bytes long. /// /// This option is mandatory for anonymous memory maps. /// /// For file-backed memory maps, the length will default to the file length. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// /// # fn main() -> std::io::Result<()> { /// let mmap = unsafe { /// MmapOptions::new() /// .len(9) /// .map(&File::open("README.md")?)? /// }; /// assert_eq!(&b"# memmap2"[..], &mmap[..]); /// # Ok(()) /// # } /// ``` pub fn len(&mut self, len: usize) -> &mut Self { self.len = Some(len); self } /// Returns the configured length, or the length of the provided file. fn get_len(&self, file: &T) -> Result { self.len.map(Ok).unwrap_or_else(|| { let desc = file.as_raw_desc(); let file_len = file_len(desc.0)?; if file_len < self.offset { return Err(Error::new( ErrorKind::InvalidData, "memory map offset is larger than length", )); } let len = file_len - self.offset; // This check it not relevant on 64bit targets, because usize == u64 #[cfg(not(target_pointer_width = "64"))] { if len > (usize::MAX as u64) { return Err(Error::new( ErrorKind::InvalidData, "memory map length overflows usize", )); } } Ok(len as usize) }) } /// Configures the anonymous memory map to be suitable for a process or thread stack. /// /// This option corresponds to the `MAP_STACK` flag on Linux. It has no effect on Windows. /// /// This option has no effect on file-backed memory maps. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// /// # fn main() -> std::io::Result<()> { /// let stack = MmapOptions::new().stack().len(4096).map_anon(); /// # Ok(()) /// # } /// ``` pub fn stack(&mut self) -> &mut Self { self.stack = true; self } /// Populate (prefault) page tables for a mapping. /// /// For a file mapping, this causes read-ahead on the file. This will help to reduce blocking on page faults later. /// /// This option corresponds to the `MAP_POPULATE` flag on Linux. It has no effect on Windows. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// /// # fn main() -> std::io::Result<()> { /// let file = File::open("LICENSE-MIT")?; /// /// let mmap = unsafe { /// MmapOptions::new().populate().map(&file)? /// }; /// /// assert_eq!(&b"Copyright"[..], &mmap[..9]); /// # Ok(()) /// # } /// ``` pub fn populate(&mut self) -> &mut Self { self.populate = true; self } /// Creates a read-only memory map backed by a file. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read permissions. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// use std::io::Read; /// /// # fn main() -> std::io::Result<()> { /// let mut file = File::open("LICENSE-APACHE")?; /// /// let mut contents = Vec::new(); /// file.read_to_end(&mut contents)?; /// /// let mmap = unsafe { /// MmapOptions::new().map(&file)? /// }; /// /// assert_eq!(&contents[..], &mmap[..]); /// # Ok(()) /// # } /// ``` pub unsafe fn map(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| Mmap { inner }) } /// Creates a readable and executable memory map backed by a file. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read permissions. pub unsafe fn map_exec(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map_exec(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| Mmap { inner: inner }) } /// Creates a writeable memory map backed by a file. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read and write permissions. /// /// # Example /// /// ``` /// # extern crate memmap2; /// # extern crate tempdir; /// # /// use std::fs::OpenOptions; /// use std::path::PathBuf; /// /// use memmap2::MmapOptions; /// # /// # fn main() -> std::io::Result<()> { /// # let tempdir = tempdir::TempDir::new("mmap")?; /// let path: PathBuf = /* path to file */ /// # tempdir.path().join("map_mut"); /// let file = OpenOptions::new().read(true).write(true).create(true).open(&path)?; /// file.set_len(13)?; /// /// let mut mmap = unsafe { /// MmapOptions::new().map_mut(&file)? /// }; /// /// mmap.copy_from_slice(b"Hello, world!"); /// # Ok(()) /// # } /// ``` pub unsafe fn map_mut(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map_mut(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| MmapMut { inner: inner }) } /// Creates a copy-on-write memory map backed by a file. /// /// Data written to the memory map will not be visible by other processes, /// and will not be carried through to the underlying file. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with writable permissions. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// use std::io::Write; /// /// # fn main() -> std::io::Result<()> { /// let file = File::open("LICENSE-APACHE")?; /// let mut mmap = unsafe { MmapOptions::new().map_copy(&file)? }; /// (&mut mmap[..]).write_all(b"Hello, world!")?; /// # Ok(()) /// # } /// ``` pub unsafe fn map_copy(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map_copy(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| MmapMut { inner: inner }) } /// Creates a copy-on-write read-only memory map backed by a file. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read permissions. /// /// # Example /// /// ``` /// use memmap2::MmapOptions; /// use std::fs::File; /// use std::io::Read; /// /// # fn main() -> std::io::Result<()> { /// let mut file = File::open("README.md")?; /// /// let mut contents = Vec::new(); /// file.read_to_end(&mut contents)?; /// /// let mmap = unsafe { /// MmapOptions::new().map_copy_read_only(&file)? /// }; /// /// assert_eq!(&contents[..], &mmap[..]); /// # Ok(()) /// # } /// ``` pub unsafe fn map_copy_read_only(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map_copy_read_only(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| Mmap { inner: inner }) } /// Creates an anonymous memory map. /// /// Note: the memory map length must be configured to be greater than 0 before creating an /// anonymous memory map using `MmapOptions::len()`. /// /// # Errors /// /// This method returns an error when the underlying system call fails. pub fn map_anon(&self) -> Result { MmapInner::map_anon(self.len.unwrap_or(0), self.stack).map(|inner| MmapMut { inner }) } /// Creates a raw memory map. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read and write permissions. pub fn map_raw(&self, file: T) -> Result { let desc = file.as_raw_desc(); MmapInner::map_mut(self.get_len(&file)?, desc.0, self.offset, self.populate) .map(|inner| MmapRaw { inner: inner }) } } /// A handle to an immutable memory mapped buffer. /// /// A `Mmap` may be backed by a file, or it can be anonymous map, backed by volatile memory. Use /// [`MmapOptions`] or [`map()`] to create a file-backed memory map. To create an immutable /// anonymous memory map, first create a mutable anonymous memory map, and then make it immutable /// with [`MmapMut::make_read_only()`]. /// /// A file backed `Mmap` is created by `&File` reference, and will remain valid even after the /// `File` is dropped. In other words, the `Mmap` handle is completely independent of the `File` /// used to create it. For consistency, on some platforms this is achieved by duplicating the /// underlying file handle. The memory will be unmapped when the `Mmap` handle is dropped. /// /// Dereferencing and accessing the bytes of the buffer may result in page faults (e.g. swapping /// the mapped pages into physical memory) though the details of this are platform specific. /// /// `Mmap` is [`Sync`](std::marker::Sync) and [`Send`](std::marker::Send). /// /// ## Safety /// /// All file-backed memory map constructors are marked `unsafe` because of the potential for /// *Undefined Behavior* (UB) using the map if the underlying file is subsequently modified, in or /// out of process. Applications must consider the risk and take appropriate precautions when using /// file-backed maps. Solutions such as file permissions, locks or process-private (e.g. unlinked) /// files exist but are platform specific and limited. /// /// ## Example /// /// ``` /// use memmap2::MmapOptions; /// use std::io::Write; /// use std::fs::File; /// /// # fn main() -> std::io::Result<()> { /// let file = File::open("README.md")?; /// let mmap = unsafe { MmapOptions::new().map(&file)? }; /// assert_eq!(b"# memmap2", &mmap[0..9]); /// # Ok(()) /// # } /// ``` /// /// See [`MmapMut`] for the mutable version. /// /// [`map()`]: Mmap::map() pub struct Mmap { inner: MmapInner, } impl Mmap { /// Creates a read-only memory map backed by a file. /// /// This is equivalent to calling `MmapOptions::new().map(file)`. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read permissions. /// /// # Example /// /// ``` /// use std::fs::File; /// use std::io::Read; /// /// use memmap2::Mmap; /// /// # fn main() -> std::io::Result<()> { /// let mut file = File::open("LICENSE-APACHE")?; /// /// let mut contents = Vec::new(); /// file.read_to_end(&mut contents)?; /// /// let mmap = unsafe { Mmap::map(&file)? }; /// /// assert_eq!(&contents[..], &mmap[..]); /// # Ok(()) /// # } /// ``` pub unsafe fn map(file: T) -> Result { MmapOptions::new().map(file) } /// Transition the memory map to be writable. /// /// If the memory map is file-backed, the file must have been opened with write permissions. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with writable permissions. /// /// # Example /// /// ``` /// # extern crate memmap2; /// # extern crate tempdir; /// # /// use memmap2::Mmap; /// use std::ops::DerefMut; /// use std::io::Write; /// # use std::fs::OpenOptions; /// /// # fn main() -> std::io::Result<()> { /// # let tempdir = tempdir::TempDir::new("mmap")?; /// let file = /* file opened with write permissions */ /// # OpenOptions::new() /// # .read(true) /// # .write(true) /// # .create(true) /// # .open(tempdir.path() /// # .join("make_mut"))?; /// # file.set_len(128)?; /// let mmap = unsafe { Mmap::map(&file)? }; /// // ... use the read-only memory map ... /// let mut mut_mmap = mmap.make_mut()?; /// mut_mmap.deref_mut().write_all(b"hello, world!")?; /// # Ok(()) /// # } /// ``` pub fn make_mut(mut self) -> Result { self.inner.make_mut()?; Ok(MmapMut { inner: self.inner }) } } impl Deref for Mmap { type Target = [u8]; #[inline] fn deref(&self) -> &[u8] { unsafe { slice::from_raw_parts(self.inner.ptr(), self.inner.len()) } } } impl AsRef<[u8]> for Mmap { #[inline] fn as_ref(&self) -> &[u8] { self.deref() } } impl fmt::Debug for Mmap { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { fmt.debug_struct("Mmap") .field("ptr", &self.as_ptr()) .field("len", &self.len()) .finish() } } /// A handle to a raw memory mapped buffer. /// /// This struct never hands out references to its interior, only raw pointers. /// This can be helpful when creating shared memory maps between untrusted processes. pub struct MmapRaw { inner: MmapInner, } impl MmapRaw { /// Creates a writeable memory map backed by a file. /// /// This is equivalent to calling `MmapOptions::new().map_raw(file)`. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read and write permissions. pub fn map_raw(file: T) -> Result { MmapOptions::new().map_raw(file) } /// Returns a raw pointer to the memory mapped file. /// /// Before dereferencing this pointer, you have to make sure that the file has not been /// truncated since the memory map was created. /// Avoiding this will not introduce memory safety issues in Rust terms, /// but will cause SIGBUS (or equivalent) signal. #[inline] pub fn as_ptr(&self) -> *const u8 { self.inner.ptr() } /// Returns an unsafe mutable pointer to the memory mapped file. /// /// Before dereferencing this pointer, you have to make sure that the file has not been /// truncated since the memory map was created. /// Avoiding this will not introduce memory safety issues in Rust terms, /// but will cause SIGBUS (or equivalent) signal. #[inline] pub fn as_mut_ptr(&self) -> *mut u8 { self.inner.ptr() as _ } /// Returns the length in bytes of the memory map. /// /// Note that truncating the file can cause the length to change (and render this value unusable). #[inline] pub fn len(&self) -> usize { self.inner.len() } } impl fmt::Debug for MmapRaw { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { fmt.debug_struct("MmapRaw") .field("ptr", &self.as_ptr()) .field("len", &self.len()) .finish() } } /// A handle to a mutable memory mapped buffer. /// /// A file-backed `MmapMut` buffer may be used to read from or write to a file. An anonymous /// `MmapMut` buffer may be used any place that an in-memory byte buffer is needed. Use /// [`MmapMut::map_mut()`] and [`MmapMut::map_anon()`] to create a mutable memory map of the /// respective types, or [`MmapOptions::map_mut()`] and [`MmapOptions::map_anon()`] if non-default /// options are required. /// /// A file backed `MmapMut` is created by `&File` reference, and will remain valid even after the /// `File` is dropped. In other words, the `MmapMut` handle is completely independent of the `File` /// used to create it. For consistency, on some platforms this is achieved by duplicating the /// underlying file handle. The memory will be unmapped when the `MmapMut` handle is dropped. /// /// Dereferencing and accessing the bytes of the buffer may result in page faults (e.g. swapping /// the mapped pages into physical memory) though the details of this are platform specific. /// /// `Mmap` is [`Sync`](std::marker::Sync) and [`Send`](std::marker::Send). /// /// See [`Mmap`] for the immutable version. /// /// ## Safety /// /// All file-backed memory map constructors are marked `unsafe` because of the potential for /// *Undefined Behavior* (UB) using the map if the underlying file is subsequently modified, in or /// out of process. Applications must consider the risk and take appropriate precautions when using /// file-backed maps. Solutions such as file permissions, locks or process-private (e.g. unlinked) /// files exist but are platform specific and limited. pub struct MmapMut { inner: MmapInner, } impl MmapMut { /// Creates a writeable memory map backed by a file. /// /// This is equivalent to calling `MmapOptions::new().map_mut(file)`. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file is not open with read and write permissions. /// /// # Example /// /// ``` /// # extern crate memmap2; /// # extern crate tempdir; /// # /// use std::fs::OpenOptions; /// use std::path::PathBuf; /// /// use memmap2::MmapMut; /// # /// # fn main() -> std::io::Result<()> { /// # let tempdir = tempdir::TempDir::new("mmap")?; /// let path: PathBuf = /* path to file */ /// # tempdir.path().join("map_mut"); /// let file = OpenOptions::new() /// .read(true) /// .write(true) /// .create(true) /// .open(&path)?; /// file.set_len(13)?; /// /// let mut mmap = unsafe { MmapMut::map_mut(&file)? }; /// /// mmap.copy_from_slice(b"Hello, world!"); /// # Ok(()) /// # } /// ``` pub unsafe fn map_mut(file: T) -> Result { MmapOptions::new().map_mut(file) } /// Creates an anonymous memory map. /// /// This is equivalent to calling `MmapOptions::new().len(length).map_anon()`. /// /// # Errors /// /// This method returns an error when the underlying system call fails. pub fn map_anon(length: usize) -> Result { MmapOptions::new().len(length).map_anon() } /// Flushes outstanding memory map modifications to disk. /// /// When this method returns with a non-error result, all outstanding changes to a file-backed /// memory map are guaranteed to be durably stored. The file's metadata (including last /// modification timestamp) may not be updated. /// /// # Example /// /// ``` /// # extern crate memmap2; /// # extern crate tempdir; /// # /// use std::fs::OpenOptions; /// use std::io::Write; /// use std::path::PathBuf; /// /// use memmap2::MmapMut; /// /// # fn main() -> std::io::Result<()> { /// # let tempdir = tempdir::TempDir::new("mmap")?; /// let path: PathBuf = /* path to file */ /// # tempdir.path().join("flush"); /// let file = OpenOptions::new().read(true).write(true).create(true).open(&path)?; /// file.set_len(128)?; /// /// let mut mmap = unsafe { MmapMut::map_mut(&file)? }; /// /// (&mut mmap[..]).write_all(b"Hello, world!")?; /// mmap.flush()?; /// # Ok(()) /// # } /// ``` pub fn flush(&self) -> Result<()> { let len = self.len(); self.inner.flush(0, len) } /// Asynchronously flushes outstanding memory map modifications to disk. /// /// This method initiates flushing modified pages to durable storage, but it will not wait for /// the operation to complete before returning. The file's metadata (including last /// modification timestamp) may not be updated. pub fn flush_async(&self) -> Result<()> { let len = self.len(); self.inner.flush_async(0, len) } /// Flushes outstanding memory map modifications in the range to disk. /// /// The offset and length must be in the bounds of the memory map. /// /// When this method returns with a non-error result, all outstanding changes to a file-backed /// memory in the range are guaranteed to be durable stored. The file's metadata (including /// last modification timestamp) may not be updated. It is not guaranteed the only the changes /// in the specified range are flushed; other outstanding changes to the memory map may be /// flushed as well. pub fn flush_range(&self, offset: usize, len: usize) -> Result<()> { self.inner.flush(offset, len) } /// Asynchronously flushes outstanding memory map modifications in the range to disk. /// /// The offset and length must be in the bounds of the memory map. /// /// This method initiates flushing modified pages to durable storage, but it will not wait for /// the operation to complete before returning. The file's metadata (including last /// modification timestamp) may not be updated. It is not guaranteed that the only changes /// flushed are those in the specified range; other outstanding changes to the memory map may /// be flushed as well. pub fn flush_async_range(&self, offset: usize, len: usize) -> Result<()> { self.inner.flush_async(offset, len) } /// Returns an immutable version of this memory mapped buffer. /// /// If the memory map is file-backed, the file must have been opened with read permissions. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file has not been opened with read permissions. /// /// # Example /// /// ``` /// # extern crate memmap2; /// # /// use std::io::Write; /// use std::path::PathBuf; /// /// use memmap2::{Mmap, MmapMut}; /// /// # fn main() -> std::io::Result<()> { /// let mut mmap = MmapMut::map_anon(128)?; /// /// (&mut mmap[..]).write(b"Hello, world!")?; /// /// let mmap: Mmap = mmap.make_read_only()?; /// # Ok(()) /// # } /// ``` pub fn make_read_only(mut self) -> Result { self.inner.make_read_only()?; Ok(Mmap { inner: self.inner }) } /// Transition the memory map to be readable and executable. /// /// If the memory map is file-backed, the file must have been opened with execute permissions. /// /// # Errors /// /// This method returns an error when the underlying system call fails, which can happen for a /// variety of reasons, such as when the file has not been opened with execute permissions. pub fn make_exec(mut self) -> Result { self.inner.make_exec()?; Ok(Mmap { inner: self.inner }) } } impl Deref for MmapMut { type Target = [u8]; #[inline] fn deref(&self) -> &[u8] { unsafe { slice::from_raw_parts(self.inner.ptr(), self.inner.len()) } } } impl DerefMut for MmapMut { #[inline] fn deref_mut(&mut self) -> &mut [u8] { unsafe { slice::from_raw_parts_mut(self.inner.mut_ptr(), self.inner.len()) } } } impl AsRef<[u8]> for MmapMut { #[inline] fn as_ref(&self) -> &[u8] { self.deref() } } impl AsMut<[u8]> for MmapMut { #[inline] fn as_mut(&mut self) -> &mut [u8] { self.deref_mut() } } impl fmt::Debug for MmapMut { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { fmt.debug_struct("MmapMut") .field("ptr", &self.as_ptr()) .field("len", &self.len()) .finish() } } #[cfg(test)] mod test { extern crate tempdir; use std::fs::OpenOptions; use std::io::{Read, Write}; #[cfg(unix)] use std::os::unix::io::AsRawFd; #[cfg(windows)] use std::os::windows::fs::OpenOptionsExt; #[cfg(windows)] const GENERIC_ALL: u32 = 0x10000000; use super::{Mmap, MmapMut, MmapOptions}; #[test] fn map_file() { let expected_len = 128; let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(expected_len as u64).unwrap(); let mut mmap = unsafe { MmapMut::map_mut(&file).unwrap() }; let len = mmap.len(); assert_eq!(expected_len, len); let zeros = vec![0; len]; let incr: Vec = (0..len as u8).collect(); // check that the mmap is empty assert_eq!(&zeros[..], &mmap[..]); // write values into the mmap (&mut mmap[..]).write_all(&incr[..]).unwrap(); // read values back assert_eq!(&incr[..], &mmap[..]); } #[test] #[cfg(unix)] fn map_fd() { let expected_len = 128; let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(expected_len as u64).unwrap(); let mut mmap = unsafe { MmapMut::map_mut(file.as_raw_fd()).unwrap() }; let len = mmap.len(); assert_eq!(expected_len, len); let zeros = vec![0; len]; let incr: Vec = (0..len as u8).collect(); // check that the mmap is empty assert_eq!(&zeros[..], &mmap[..]); // write values into the mmap (&mut mmap[..]).write_all(&incr[..]).unwrap(); // read values back assert_eq!(&incr[..], &mmap[..]); } /// Checks that a 0-length file will not be mapped. #[test] fn map_empty_file() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); let mmap = unsafe { Mmap::map(&file) }; assert!(mmap.is_err()); } #[test] fn map_anon() { let expected_len = 128; let mut mmap = MmapMut::map_anon(expected_len).unwrap(); let len = mmap.len(); assert_eq!(expected_len, len); let zeros = vec![0; len]; let incr: Vec = (0..len as u8).collect(); // check that the mmap is empty assert_eq!(&zeros[..], &mmap[..]); // write values into the mmap (&mut mmap[..]).write_all(&incr[..]).unwrap(); // read values back assert_eq!(&incr[..], &mmap[..]); } #[test] fn map_anon_zero_len() { assert!(MmapOptions::new().map_anon().is_err()) } #[test] fn file_write() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let mut file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(128).unwrap(); let write = b"abc123"; let mut read = [0u8; 6]; let mut mmap = unsafe { MmapMut::map_mut(&file).unwrap() }; (&mut mmap[..]).write_all(write).unwrap(); mmap.flush().unwrap(); file.read_exact(&mut read).unwrap(); assert_eq!(write, &read); } #[test] fn flush_range() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(128).unwrap(); let write = b"abc123"; let mut mmap = unsafe { MmapOptions::new() .offset(2) .len(write.len()) .map_mut(&file) .unwrap() }; (&mut mmap[..]).write_all(write).unwrap(); mmap.flush_async_range(0, write.len()).unwrap(); mmap.flush_range(0, write.len()).unwrap(); } #[test] fn map_copy() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let mut file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(128).unwrap(); let nulls = b"\0\0\0\0\0\0"; let write = b"abc123"; let mut read = [0u8; 6]; let mut mmap = unsafe { MmapOptions::new().map_copy(&file).unwrap() }; (&mut mmap[..]).write_all(write).unwrap(); mmap.flush().unwrap(); // The mmap contains the write (&mmap[..]).read_exact(&mut read).unwrap(); assert_eq!(write, &read); // The file does not contain the write file.read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); // another mmap does not contain the write let mmap2 = unsafe { MmapOptions::new().map(&file).unwrap() }; (&mmap2[..]).read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); } #[test] fn map_copy_read_only() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); file.set_len(128).unwrap(); let nulls = b"\0\0\0\0\0\0"; let mut read = [0u8; 6]; let mmap = unsafe { MmapOptions::new().map_copy_read_only(&file).unwrap() }; (&mmap[..]).read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); let mmap2 = unsafe { MmapOptions::new().map(&file).unwrap() }; (&mmap2[..]).read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); } // 32bit Linux cannot map a file larger than i32, but Windows can. #[cfg(all(target_os = "linux", target_pointer_width = "32"))] #[test] fn map_offset() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); let offset = u32::max_value() as u64 + 2; let len = 5432; file.set_len(offset + len as u64).unwrap(); let mmap = unsafe { MmapOptions::new().offset(offset).map_mut(&file) }; assert!(mmap.is_err()); } #[cfg(not(all(target_os = "linux", target_pointer_width = "32")))] #[test] fn map_offset() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let file = OpenOptions::new() .read(true) .write(true) .create(true) .open(&path) .unwrap(); let offset = u32::max_value() as u64 + 2; let len = 5432; file.set_len(offset + len as u64).unwrap(); // Check inferred length mmap. let mmap = unsafe { MmapOptions::new().offset(offset).map_mut(&file).unwrap() }; assert_eq!(len, mmap.len()); // Check explicit length mmap. let mut mmap = unsafe { MmapOptions::new() .offset(offset) .len(len) .map_mut(&file) .unwrap() }; assert_eq!(len, mmap.len()); let zeros = vec![0; len]; let incr: Vec<_> = (0..len).map(|i| i as u8).collect(); // check that the mmap is empty assert_eq!(&zeros[..], &mmap[..]); // write values into the mmap (&mut mmap[..]).write_all(&incr[..]).unwrap(); // read values back assert_eq!(&incr[..], &mmap[..]); } #[test] fn index() { let mut mmap = MmapMut::map_anon(128).unwrap(); mmap[0] = 42; assert_eq!(42, mmap[0]); } #[test] fn sync_send() { let mmap = MmapMut::map_anon(129).unwrap(); fn is_sync_send(_val: T) where T: Sync + Send, { } is_sync_send(mmap); } #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] fn jit_x86(mut mmap: MmapMut) { use std::mem; mmap[0] = 0xB8; // mov eax, 0xAB mmap[1] = 0xAB; mmap[2] = 0x00; mmap[3] = 0x00; mmap[4] = 0x00; mmap[5] = 0xC3; // ret let mmap = mmap.make_exec().expect("make_exec"); let jitfn: extern "C" fn() -> u8 = unsafe { mem::transmute(mmap.as_ptr()) }; assert_eq!(jitfn(), 0xab); } #[test] #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] fn jit_x86_anon() { jit_x86(MmapMut::map_anon(4096).unwrap()); } #[test] #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] fn jit_x86_file() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let mut options = OpenOptions::new(); #[cfg(windows)] options.access_mode(GENERIC_ALL); let file = options .read(true) .write(true) .create(true) .open(&tempdir.path().join("jit_x86")) .expect("open"); file.set_len(4096).expect("set_len"); jit_x86(unsafe { MmapMut::map_mut(&file).expect("map_mut") }); } #[test] fn mprotect_file() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let mut options = OpenOptions::new(); #[cfg(windows)] options.access_mode(GENERIC_ALL); let mut file = options .read(true) .write(true) .create(true) .open(&path) .expect("open"); file.set_len(256_u64).expect("set_len"); let mmap = unsafe { MmapMut::map_mut(&file).expect("map_mut") }; let mmap = mmap.make_read_only().expect("make_read_only"); let mut mmap = mmap.make_mut().expect("make_mut"); let write = b"abc123"; let mut read = [0u8; 6]; (&mut mmap[..]).write_all(write).unwrap(); mmap.flush().unwrap(); // The mmap contains the write (&mmap[..]).read_exact(&mut read).unwrap(); assert_eq!(write, &read); // The file should contain the write file.read_exact(&mut read).unwrap(); assert_eq!(write, &read); // another mmap should contain the write let mmap2 = unsafe { MmapOptions::new().map(&file).unwrap() }; (&mmap2[..]).read_exact(&mut read).unwrap(); assert_eq!(write, &read); let mmap = mmap.make_exec().expect("make_exec"); drop(mmap); } #[test] fn mprotect_copy() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmap"); let mut options = OpenOptions::new(); #[cfg(windows)] options.access_mode(GENERIC_ALL); let mut file = options .read(true) .write(true) .create(true) .open(&path) .expect("open"); file.set_len(256_u64).expect("set_len"); let mmap = unsafe { MmapOptions::new().map_copy(&file).expect("map_mut") }; let mmap = mmap.make_read_only().expect("make_read_only"); let mut mmap = mmap.make_mut().expect("make_mut"); let nulls = b"\0\0\0\0\0\0"; let write = b"abc123"; let mut read = [0u8; 6]; (&mut mmap[..]).write_all(write).unwrap(); mmap.flush().unwrap(); // The mmap contains the write (&mmap[..]).read_exact(&mut read).unwrap(); assert_eq!(write, &read); // The file does not contain the write file.read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); // another mmap does not contain the write let mmap2 = unsafe { MmapOptions::new().map(&file).unwrap() }; (&mmap2[..]).read_exact(&mut read).unwrap(); assert_eq!(nulls, &read); let mmap = mmap.make_exec().expect("make_exec"); drop(mmap); } #[test] fn mprotect_anon() { let mmap = MmapMut::map_anon(256).expect("map_mut"); let mmap = mmap.make_read_only().expect("make_read_only"); let mmap = mmap.make_mut().expect("make_mut"); let mmap = mmap.make_exec().expect("make_exec"); drop(mmap); } #[test] fn raw() { let tempdir = tempdir::TempDir::new("mmap").unwrap(); let path = tempdir.path().join("mmapraw"); let mut options = OpenOptions::new(); let mut file = options .read(true) .write(true) .create(true) .open(&path) .expect("open"); file.write_all(b"abc123").unwrap(); let mmap = MmapOptions::new().map_raw(&file).unwrap(); assert_eq!(mmap.len(), 6); assert!(!mmap.as_ptr().is_null()); assert_eq!(unsafe { std::ptr::read(mmap.as_ptr()) }, b'a'); } } memmap2-0.3.1/src/stub.rs000064400000000000000000000037270000000000000132630ustar 00000000000000use std::fs::File; use std::io; pub struct MmapInner { // Private member to prevent external construction // (might be nice to change the type to ! once that's stable) __: (), } impl MmapInner { fn new() -> io::Result { Err(io::Error::new( io::ErrorKind::Other, "platform not supported", )) } pub fn map(_: usize, _: &File, _: u64, _: bool) -> io::Result { MmapInner::new() } pub fn map_exec(_: usize, _: &File, _: u64, _: bool) -> io::Result { MmapInner::new() } pub fn map_mut(_: usize, _: &File, _: u64, _: bool) -> io::Result { MmapInner::new() } pub fn map_copy(_: usize, _: &File, _: u64, _: bool) -> io::Result { MmapInner::new() } pub fn map_copy_read_only(_: usize, _: &File, _: u64, _: bool) -> io::Result { MmapInner::new() } pub fn map_anon(_: usize, _: bool) -> io::Result { MmapInner::new() } pub fn flush(&self, _: usize, _: usize) -> io::Result<()> { unreachable!("self unconstructable"); } pub fn flush_async(&self, _: usize, _: usize) -> io::Result<()> { unreachable!("self unconstructable"); } pub fn make_read_only(&mut self) -> io::Result<()> { unreachable!("self unconstructable"); } pub fn make_exec(&mut self) -> io::Result<()> { unreachable!("self unconstructable"); } pub fn make_mut(&mut self) -> io::Result<()> { unreachable!("self unconstructable"); } #[inline] pub fn ptr(&self) -> *const u8 { unreachable!("self unconstructable"); } #[inline] pub fn mut_ptr(&mut self) -> *mut u8 { unreachable!("self unconstructable"); } #[inline] pub fn len(&self) -> usize { unreachable!("self unconstructable"); } } pub fn file_len(file: &File) -> io::Result { Ok(file.metadata()?.len()) } memmap2-0.3.1/src/unix.rs000064400000000000000000000154130000000000000132640ustar 00000000000000extern crate libc; use std::os::unix::io::RawFd; use std::{io, ptr}; #[cfg(any( all(target_os = "linux", not(target_arch = "mips")), target_os = "freebsd", target_os = "android" ))] const MAP_STACK: libc::c_int = libc::MAP_STACK; #[cfg(not(any( all(target_os = "linux", not(target_arch = "mips")), target_os = "freebsd", target_os = "android" )))] const MAP_STACK: libc::c_int = 0; #[cfg(any(target_os = "linux", target_os = "android"))] const MAP_POPULATE: libc::c_int = libc::MAP_POPULATE; #[cfg(not(any(target_os = "linux", target_os = "android")))] const MAP_POPULATE: libc::c_int = 0; pub struct MmapInner { ptr: *mut libc::c_void, len: usize, } impl MmapInner { /// Creates a new `MmapInner`. /// /// This is a thin wrapper around the `mmap` sytem call. fn new( len: usize, prot: libc::c_int, flags: libc::c_int, file: RawFd, offset: u64, ) -> io::Result { let alignment = offset % page_size() as u64; let aligned_offset = offset - alignment; let aligned_len = len + alignment as usize; if aligned_len == 0 { // Normally the OS would catch this, but it segfaults under QEMU. return Err(io::Error::new( io::ErrorKind::InvalidInput, "memory map must have a non-zero length", )); } unsafe { let ptr = libc::mmap( ptr::null_mut(), aligned_len as libc::size_t, prot, flags, file, aligned_offset as libc::off_t, ); if ptr == libc::MAP_FAILED { Err(io::Error::last_os_error()) } else { Ok(MmapInner { ptr: ptr.offset(alignment as isize), len, }) } } } pub fn map(len: usize, file: RawFd, offset: u64, populate: bool) -> io::Result { let populate = if populate { MAP_POPULATE } else { 0 }; MmapInner::new( len, libc::PROT_READ, libc::MAP_SHARED | populate, file, offset, ) } pub fn map_exec(len: usize, file: RawFd, offset: u64, populate: bool) -> io::Result { let populate = if populate { MAP_POPULATE } else { 0 }; MmapInner::new( len, libc::PROT_READ | libc::PROT_EXEC, libc::MAP_SHARED | populate, file, offset, ) } pub fn map_mut(len: usize, file: RawFd, offset: u64, populate: bool) -> io::Result { let populate = if populate { MAP_POPULATE } else { 0 }; MmapInner::new( len, libc::PROT_READ | libc::PROT_WRITE, libc::MAP_SHARED | populate, file, offset, ) } pub fn map_copy(len: usize, file: RawFd, offset: u64, populate: bool) -> io::Result { let populate = if populate { MAP_POPULATE } else { 0 }; MmapInner::new( len, libc::PROT_READ | libc::PROT_WRITE, libc::MAP_PRIVATE | populate, file, offset, ) } pub fn map_copy_read_only( len: usize, file: RawFd, offset: u64, populate: bool, ) -> io::Result { let populate = if populate { MAP_POPULATE } else { 0 }; MmapInner::new( len, libc::PROT_READ, libc::MAP_PRIVATE | populate, file, offset, ) } /// Open an anonymous memory map. pub fn map_anon(len: usize, stack: bool) -> io::Result { let stack = if stack { MAP_STACK } else { 0 }; MmapInner::new( len, libc::PROT_READ | libc::PROT_WRITE, libc::MAP_PRIVATE | libc::MAP_ANON | stack, -1, 0, ) } pub fn flush(&self, offset: usize, len: usize) -> io::Result<()> { let alignment = (self.ptr as usize + offset) % page_size(); let offset = offset as isize - alignment as isize; let len = len + alignment; let result = unsafe { libc::msync(self.ptr.offset(offset), len as libc::size_t, libc::MS_SYNC) }; if result == 0 { Ok(()) } else { Err(io::Error::last_os_error()) } } pub fn flush_async(&self, offset: usize, len: usize) -> io::Result<()> { let alignment = (self.ptr as usize + offset) % page_size(); let offset = offset as isize - alignment as isize; let len = len + alignment; let result = unsafe { libc::msync(self.ptr.offset(offset), len as libc::size_t, libc::MS_ASYNC) }; if result == 0 { Ok(()) } else { Err(io::Error::last_os_error()) } } fn mprotect(&mut self, prot: libc::c_int) -> io::Result<()> { unsafe { let alignment = self.ptr as usize % page_size(); let ptr = self.ptr.offset(-(alignment as isize)); let len = self.len + alignment; if libc::mprotect(ptr, len, prot) == 0 { Ok(()) } else { Err(io::Error::last_os_error()) } } } pub fn make_read_only(&mut self) -> io::Result<()> { self.mprotect(libc::PROT_READ) } pub fn make_exec(&mut self) -> io::Result<()> { self.mprotect(libc::PROT_READ | libc::PROT_EXEC) } pub fn make_mut(&mut self) -> io::Result<()> { self.mprotect(libc::PROT_READ | libc::PROT_WRITE) } #[inline] pub fn ptr(&self) -> *const u8 { self.ptr as *const u8 } #[inline] pub fn mut_ptr(&mut self) -> *mut u8 { self.ptr as *mut u8 } #[inline] pub fn len(&self) -> usize { self.len } } impl Drop for MmapInner { fn drop(&mut self) { let alignment = self.ptr as usize % page_size(); unsafe { assert!( libc::munmap( self.ptr.offset(-(alignment as isize)), (self.len + alignment) as libc::size_t ) == 0, "unable to unmap mmap: {}", io::Error::last_os_error() ); } } } unsafe impl Sync for MmapInner {} unsafe impl Send for MmapInner {} fn page_size() -> usize { unsafe { libc::sysconf(libc::_SC_PAGESIZE) as usize } } pub fn file_len(file: RawFd) -> io::Result { unsafe { let mut stat: libc::stat = std::mem::zeroed(); let result = libc::fstat(file, &mut stat); if result == 0 { Ok(stat.st_size as u64) } else { Err(io::Error::last_os_error()) } } } memmap2-0.3.1/src/windows.rs000064400000000000000000000305000000000000000137650ustar 00000000000000#![allow(non_camel_case_types)] #![allow(non_snake_case)] use std::fs::File; use std::os::raw::c_void; use std::os::windows::io::{AsRawHandle, RawHandle}; use std::{io, mem, ptr}; type BOOL = i32; type WORD = u16; type DWORD = u32; type WCHAR = u16; type HANDLE = *mut c_void; type LPVOID = *mut c_void; type LPCVOID = *const c_void; type ULONG_PTR = usize; type SIZE_T = ULONG_PTR; type LPCWSTR = *const WCHAR; type PDWORD = *mut DWORD; type DWORD_PTR = ULONG_PTR; type LPSECURITY_ATTRIBUTES = *mut SECURITY_ATTRIBUTES; type LPSYSTEM_INFO = *mut SYSTEM_INFO; const INVALID_HANDLE_VALUE: HANDLE = -1isize as HANDLE; const STANDARD_RIGHTS_REQUIRED: DWORD = 0x000F0000; const SECTION_QUERY: DWORD = 0x0001; const SECTION_MAP_WRITE: DWORD = 0x0002; const SECTION_MAP_READ: DWORD = 0x0004; const SECTION_MAP_EXECUTE: DWORD = 0x0008; const SECTION_EXTEND_SIZE: DWORD = 0x0010; const SECTION_MAP_EXECUTE_EXPLICIT: DWORD = 0x0020; const SECTION_ALL_ACCESS: DWORD = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_WRITE | SECTION_MAP_READ | SECTION_MAP_EXECUTE | SECTION_EXTEND_SIZE; const PAGE_READONLY: DWORD = 0x02; const PAGE_READWRITE: DWORD = 0x04; const PAGE_WRITECOPY: DWORD = 0x08; const PAGE_EXECUTE_READ: DWORD = 0x20; const PAGE_EXECUTE_READWRITE: DWORD = 0x40; const PAGE_EXECUTE_WRITECOPY: DWORD = 0x80; const FILE_MAP_WRITE: DWORD = SECTION_MAP_WRITE; const FILE_MAP_READ: DWORD = SECTION_MAP_READ; const FILE_MAP_ALL_ACCESS: DWORD = SECTION_ALL_ACCESS; const FILE_MAP_EXECUTE: DWORD = SECTION_MAP_EXECUTE_EXPLICIT; const FILE_MAP_COPY: DWORD = 0x00000001; #[repr(C)] #[derive(Clone, Copy)] struct SECURITY_ATTRIBUTES { nLength: DWORD, lpSecurityDescriptor: LPVOID, bInheritHandle: BOOL, } #[repr(C)] #[derive(Clone, Copy)] struct SYSTEM_INFO_u_s { wProcessorArchitecture: WORD, wReserved: WORD, } #[repr(C)] #[derive(Clone, Copy)] struct SYSTEM_INFO_u([u32; 1]); #[repr(C)] #[derive(Clone, Copy)] struct SYSTEM_INFO { u: SYSTEM_INFO_u, dwPageSize: DWORD, lpMinimumApplicationAddress: LPVOID, lpMaximumApplicationAddress: LPVOID, dwActiveProcessorMask: DWORD_PTR, dwNumberOfProcessors: DWORD, dwProcessorType: DWORD, dwAllocationGranularity: DWORD, wProcessorLevel: WORD, wProcessorRevision: WORD, } extern "system" { fn CloseHandle(hObject: HANDLE) -> BOOL; fn CreateFileMappingW( hFile: HANDLE, lpFileMappingAttributes: LPSECURITY_ATTRIBUTES, flProtect: DWORD, dwMaximumSizeHigh: DWORD, dwMaximumSizeLow: DWORD, lpName: LPCWSTR, ) -> HANDLE; fn FlushViewOfFile(lpBaseAddress: LPCVOID, dwNumberOfBytesToFlush: SIZE_T) -> BOOL; fn UnmapViewOfFile(lpBaseAddress: LPCVOID) -> BOOL; fn MapViewOfFile( hFileMappingObject: HANDLE, dwDesiredAccess: DWORD, dwFileOffsetHigh: DWORD, dwFileOffsetLow: DWORD, dwNumberOfBytesToMap: SIZE_T, ) -> LPVOID; fn VirtualProtect( lpAddress: LPVOID, dwSize: SIZE_T, flNewProtect: DWORD, lpflOldProtect: PDWORD, ) -> BOOL; fn GetSystemInfo(lpSystemInfo: LPSYSTEM_INFO); } pub struct MmapInner { file: Option, ptr: *mut c_void, len: usize, copy: bool, } impl MmapInner { /// Creates a new `MmapInner`. /// /// This is a thin wrapper around the `CreateFileMappingW` and `MapViewOfFile` system calls. pub fn new( file: &File, protect: DWORD, access: DWORD, offset: u64, len: usize, copy: bool, ) -> io::Result { let alignment = offset % allocation_granularity() as u64; let aligned_offset = offset - alignment as u64; let aligned_len = len + alignment as usize; unsafe { let handle = CreateFileMappingW( file.as_raw_handle(), ptr::null_mut(), protect, 0, 0, ptr::null(), ); if handle.is_null() { return Err(io::Error::last_os_error()); } let ptr = MapViewOfFile( handle, access, (aligned_offset >> 16 >> 16) as DWORD, (aligned_offset & 0xffffffff) as DWORD, aligned_len as SIZE_T, ); CloseHandle(handle); if ptr.is_null() { Err(io::Error::last_os_error()) } else { Ok(MmapInner { file: Some(file.try_clone()?), ptr: ptr.offset(alignment as isize), len: len as usize, copy, }) } } } pub fn map(len: usize, file: &File, offset: u64, _populate: bool) -> io::Result { let write = protection_supported(file.as_raw_handle(), PAGE_READWRITE); let exec = protection_supported(file.as_raw_handle(), PAGE_EXECUTE_READ); let mut access = FILE_MAP_READ; let protection = match (write, exec) { (true, true) => { access |= FILE_MAP_WRITE | FILE_MAP_EXECUTE; PAGE_EXECUTE_READWRITE } (true, false) => { access |= FILE_MAP_WRITE; PAGE_READWRITE } (false, true) => { access |= FILE_MAP_EXECUTE; PAGE_EXECUTE_READ } (false, false) => PAGE_READONLY, }; let mut inner = MmapInner::new(file, protection, access, offset, len, false)?; if write || exec { inner.make_read_only()?; } Ok(inner) } pub fn map_exec( len: usize, file: &File, offset: u64, _populate: bool, ) -> io::Result { let write = protection_supported(file.as_raw_handle(), PAGE_READWRITE); let mut access = FILE_MAP_READ | FILE_MAP_EXECUTE; let protection = if write { access |= FILE_MAP_WRITE; PAGE_EXECUTE_READWRITE } else { PAGE_EXECUTE_READ }; let mut inner = MmapInner::new(file, protection, access, offset, len, false)?; if write { inner.make_exec()?; } Ok(inner) } pub fn map_mut(len: usize, file: &File, offset: u64, _populate: bool) -> io::Result { let exec = protection_supported(file.as_raw_handle(), PAGE_EXECUTE_READ); let mut access = FILE_MAP_READ | FILE_MAP_WRITE; let protection = if exec { access |= FILE_MAP_EXECUTE; PAGE_EXECUTE_READWRITE } else { PAGE_READWRITE }; let mut inner = MmapInner::new(file, protection, access, offset, len, false)?; if exec { inner.make_mut()?; } Ok(inner) } pub fn map_copy( len: usize, file: &File, offset: u64, _populate: bool, ) -> io::Result { let exec = protection_supported(file.as_raw_handle(), PAGE_EXECUTE_READWRITE); let mut access = FILE_MAP_COPY; let protection = if exec { access |= FILE_MAP_EXECUTE; PAGE_EXECUTE_WRITECOPY } else { PAGE_WRITECOPY }; let mut inner = MmapInner::new(file, protection, access, offset, len, true)?; if exec { inner.make_mut()?; } Ok(inner) } pub fn map_copy_read_only( len: usize, file: &File, offset: u64, _populate: bool, ) -> io::Result { let write = protection_supported(file.as_raw_handle(), PAGE_READWRITE); let exec = protection_supported(file.as_raw_handle(), PAGE_EXECUTE_READ); let mut access = FILE_MAP_COPY; let protection = if exec { access |= FILE_MAP_EXECUTE; PAGE_EXECUTE_WRITECOPY } else { PAGE_WRITECOPY }; let mut inner = MmapInner::new(file, protection, access, offset, len, true)?; if write || exec { inner.make_read_only()?; } Ok(inner) } pub fn map_anon(len: usize, _stack: bool) -> io::Result { unsafe { // Create a mapping and view with maximum access permissions, then use `VirtualProtect` // to set the actual `Protection`. This way, we can set more permissive protection later // on. // Also see https://msdn.microsoft.com/en-us/library/windows/desktop/aa366537.aspx let handle = CreateFileMappingW( INVALID_HANDLE_VALUE, ptr::null_mut(), PAGE_EXECUTE_READWRITE, (len >> 16 >> 16) as DWORD, (len & 0xffffffff) as DWORD, ptr::null(), ); if handle.is_null() { return Err(io::Error::last_os_error()); } let access = FILE_MAP_ALL_ACCESS | FILE_MAP_EXECUTE; let ptr = MapViewOfFile(handle, access, 0, 0, len as SIZE_T); CloseHandle(handle); if ptr.is_null() { return Err(io::Error::last_os_error()); } let mut old = 0; let result = VirtualProtect(ptr, len as SIZE_T, PAGE_READWRITE, &mut old); if result != 0 { Ok(MmapInner { file: None, ptr, len: len as usize, copy: false, }) } else { Err(io::Error::last_os_error()) } } } pub fn flush(&self, offset: usize, len: usize) -> io::Result<()> { self.flush_async(offset, len)?; if let Some(ref file) = self.file { file.sync_data()?; } Ok(()) } pub fn flush_async(&self, offset: usize, len: usize) -> io::Result<()> { let result = unsafe { FlushViewOfFile(self.ptr.add(offset), len as SIZE_T) }; if result != 0 { Ok(()) } else { Err(io::Error::last_os_error()) } } fn virtual_protect(&mut self, protect: DWORD) -> io::Result<()> { unsafe { let alignment = self.ptr as usize % allocation_granularity(); let ptr = self.ptr.offset(-(alignment as isize)); let aligned_len = self.len as SIZE_T + alignment as SIZE_T; let mut old = 0; let result = VirtualProtect(ptr, aligned_len, protect, &mut old); if result != 0 { Ok(()) } else { Err(io::Error::last_os_error()) } } } pub fn make_read_only(&mut self) -> io::Result<()> { self.virtual_protect(PAGE_READONLY) } pub fn make_exec(&mut self) -> io::Result<()> { if self.copy { self.virtual_protect(PAGE_EXECUTE_WRITECOPY) } else { self.virtual_protect(PAGE_EXECUTE_READ) } } pub fn make_mut(&mut self) -> io::Result<()> { if self.copy { self.virtual_protect(PAGE_WRITECOPY) } else { self.virtual_protect(PAGE_READWRITE) } } #[inline] pub fn ptr(&self) -> *const u8 { self.ptr as *const u8 } #[inline] pub fn mut_ptr(&mut self) -> *mut u8 { self.ptr as *mut u8 } #[inline] pub fn len(&self) -> usize { self.len } } impl Drop for MmapInner { fn drop(&mut self) { let alignment = self.ptr as usize % allocation_granularity(); unsafe { let ptr = self.ptr.offset(-(alignment as isize)); assert!( UnmapViewOfFile(ptr) != 0, "unable to unmap mmap: {}", io::Error::last_os_error() ); } } } unsafe impl Sync for MmapInner {} unsafe impl Send for MmapInner {} fn protection_supported(handle: RawHandle, protection: DWORD) -> bool { unsafe { let handle = CreateFileMappingW(handle, ptr::null_mut(), protection, 0, 0, ptr::null()); if handle.is_null() { return false; } CloseHandle(handle); true } } fn allocation_granularity() -> usize { unsafe { let mut info = mem::zeroed(); GetSystemInfo(&mut info); info.dwAllocationGranularity as usize } } pub fn file_len(file: &File) -> io::Result { Ok(file.metadata()?.len()) }