1# Using Rust Toolchain 2 3## Introduction 4 5This document walks you through on how to compile Rust applications to make them suitable for running with OpenHarmony OS. 6 7Rust is a static, strongly typed programming language. It has advantages such as secure memory management, high running performance, and native support for multi-thread development. 8 9This toolchain is developed based on the open-source Rust and LLVM and adapts to OpenHarmony OS target binary builds. You can use it to convert build Rust source code into the binary code that can run on OpenHarmony devices. 10 11 12## When to Use 13 14- Compile Linux x86 target binaries or cross-compile OpenHarmony target binaries in a Linux x86 environment. 15- Compile MacOS x86 target binaries in a MacOS x86 environment. 16- Compile MacOS arm64 target binaries in a MacOS arm64 environment. 17 18## How to Use 19 20### Compiling OpenHarmony Community Code 21 221. Download or update the OpenHarmony community code. For details, see [Obtaining Source Code](../get-code/sourcecode-acquire.md). 23 242. Download and install the toolchain. 25 26 ```shell 27 ./build/prebuilts_download.sh 28 ``` 29 303. Prepare the code to be compiled. 31 32 Create the **build/rust/tests/test_bin_crate** directory and the following files and folders in the directory: 33 34 ```shell 35 ├── BUILD.gn 36 └── src 37 └── main.rs 38 ``` 39 40 Sample code of **main.rs**: 41 42 ```rust 43 //! Hello world example for Rust. 44 45 fn main() { 46 println!("Hello, world!"); 47 println!(env!("RUSTENV_TEST")); 48 } 49 ``` 50 51 Sample code of **BUILD.gn**: 52 53 ```shell 54 import("//build/ohos.gni") 55 56 ohos_rust_executable("test_bin_crate") { 57 sources = [ "src/main.rs" ] 58 rustenv = [ "RUSTENV_TEST=123" ] 59 features = [ "std" ] 60 if (is_mingw) { 61 rust_static_link = true 62 } 63 } 64 ``` 65 664. Run the following command to build the target: 67 68 ```shell 69 ./build.sh --product-name {product_name} --build-target 70 ``` 71 72 The following uses RK3568 as an example. 73 74 ```shell 75 ./build.sh --product-name rk3568 --build-target build/rust/tests/test_bin_crate:test_bin_crate –no-prebuilt-sdk 76 ``` 77 78 You can find the file generated in the following directory: 79 80 ```shell 81 ./out/rk3568/build/build_framework/test_bin_crate 82 ``` 83 84### Compiling Non-OpenHarmony Community Code 85 86#### Installing the Rust Toolchain 87 881. Download the build repository code. 89 90 ```shell 91 git clone git@gitee.com:openharmony/build.git 92 ``` 93 942. Download and install the toolchain. 95 96 ```shell 97 ./build/prebuilts_download.sh 98 ``` 99 1003. Check whether the toolchain is successfully installed. 101 102 ```shell 103 ./prebuilts/rustc/linux-x86_64/current/bin/rustc --version 104 ``` 105 106 The toolchain is installed if information similar to the following is displayed: 107 108 ```shell 109 rustc 1.72.0-nightly (xxxx) 110 ``` 111 112#### Installing OpenHarmony Clang 113 114>**NOTE** 115> 116>This tool is used to cross-compile the OpenHarmony target in a Linux x86 environment. You do not need to install it if you do not want to compile the OpenHarmony target. 117 1181. Obtain the SDK download path from the latest OpenHarmony [release notes](../../release-notes/Readme.md). 119 120  121 1222. Download the SDK package for Linux and decompress the packages in sequence. 123 124 ```shell 125 mv ohos-sdk-windows_linux-public.tar.gz /opt/ 126 cd /opt/ 127 tar -zxvf ohos-sdk-windows_linux-public.tar.gz 128 cd ohos-sdk/linux 129 unzip native-linux-x64-4.1.7.5-Release.zip 130 ``` 131 132#### Compiling Source Code 133 1341. Obtain the Rust source file **main.rs**. 135 136 ```rust 137 fn main() { 138 println!("hello world"); 139 } 140 ``` 141 1422. Compile the Rust source file **main.rs** for the host platform, which is **linux-x86_64**. 143 144 ```shell 145 ./prebuilts/rustc/linux-x86_64/current/bin/rustc main.rs 146 ``` 147 148 The build result is as follows: 149 150 ```shell 151 ./main 152 hello world 153 ``` 154 1553. Cross-compile the Rust source file **main.rs** for the target architecture **armv7-unknown-linux-ohos**, which is armv7 with the OpenHarmony OS. 156 157 ```shell 158 ./prebuilts/rustc/linux-x86_64/current/bin/rustc main.rs --target=armv7-unknown-linux-ohos -C linker=/opt/ohos-sdk/linux/native/llvm/bin/armv7-unknown-linux-ohos-clang 159 ``` 160 1614. Cross-compile the Rust source file **main.rs** for the target architecture **aarch64-unknown-linux-ohos**, which is aarch64 with the OpenHarmony OS. 162 163 ```shell 164 ./prebuilts/rustc/linux-x86_64/current/bin/rustc main.rs --target=aarch64-unknown-linux-ohos -C linker=/opt/ohos-sdk/linux/native/llvm/bin/aarch64-unknown-linux-ohos-clang 165 ``` 166 1675. Cross-compile the Rust source file **main.rs** for the target architecture **x86_64-unknown-linux-ohos**, which is x86_64 with the OpenHarmony OS. 168 169 ```shell 170 ./prebuilts/rustc/linux-x86_64/current/bin/rustc main.rs --target=x86_64-unknown-linux-ohos -C linker=/opt/ohos-sdk/linux/native/llvm/bin/x86_64-unknown-linux-ohos-clang 171 ``` 172
