1 [](https://github.com/FreeRTOS/FreeRTOS-Kernel/actions/workflows/unit-tests.yml?query=branch%3Amain+event%3Apush+workflow%3A%22CMock+Unit+Tests%22++)
2 [](https://codecov.io/gh/FreeRTOS/FreeRTOS-Kernel)
6 This repository contains FreeRTOS kernel source/header files and kernel
7 ports only. This repository is referenced as a submodule in
8 [FreeRTOS/FreeRTOS](https://github.com/FreeRTOS/FreeRTOS)
9 repository, which contains pre-configured demo application projects under
10 ```FreeRTOS/Demo``` directory.
12 The easiest way to use FreeRTOS is to start with one of the pre-configured demo
13 application projects. That way you will have the correct FreeRTOS source files
14 included, and the correct include paths configured. Once a demo application is
15 building and executing you can remove the demo application files, and start to
16 add in your own application source files. See the
17 [FreeRTOS Kernel Quick Start Guide](https://www.FreeRTOS.org/FreeRTOS-quick-start-guide.html)
18 for detailed instructions and other useful links.
20 Additionally, for FreeRTOS kernel feature information refer to the
21 [Developer Documentation](https://www.FreeRTOS.org/features.html),
22 and [API Reference](https://www.FreeRTOS.org/a00106.html).
24 Also for contributing and creating a Pull Request please refer to
25 [the instructions here](.github/CONTRIBUTING.md#contributing-via-pull-request).
29 If you have any questions or need assistance troubleshooting your FreeRTOS project,
30 we have an active community that can help on the
31 [FreeRTOS Community Support Forum](https://forums.freertos.org).
33 ## To consume FreeRTOS-Kernel
35 ### Consume with CMake
37 If using CMake, it is recommended to use this repository using FetchContent.
38 Add the following into your project's main or a subdirectory's `CMakeLists.txt`:
40 - Define the source and version/tag you want to use:
43 FetchContent_Declare( freertos_kernel
44 GIT_REPOSITORY https://github.com/FreeRTOS/FreeRTOS-Kernel.git
45 GIT_TAG main #Note: Best practice to use specific git-hash or tagged version
49 In case you prefer to add it as a git submodule, do:
52 git submodule add https://github.com/FreeRTOS/FreeRTOS-Kernel.git <path of the submodule>
53 git submodule update --init
56 - Add a freertos_config library (typically an INTERFACE library) The following assumes the directory structure:
57 - `include/FreeRTOSConfig.h`
60 add_library(freertos_config INTERFACE)
62 target_include_directories(freertos_config SYSTEM
67 target_compile_definitions(freertos_config
73 In case you installed FreeRTOS-Kernel as a submodule, you will have to add it as a subdirectory:
76 add_subdirectory(${FREERTOS_PATH})
79 - Configure the FreeRTOS-Kernel and make it available
80 - this particular example supports a native and cross-compiled build option.
83 set( FREERTOS_HEAP "4" CACHE STRING "" FORCE)
84 # Select the native compile PORT
85 set( FREERTOS_PORT "GCC_POSIX" CACHE STRING "" FORCE)
86 # Select the cross-compile PORT
87 if (CMAKE_CROSSCOMPILING)
88 set(FREERTOS_PORT "GCC_ARM_CA9" CACHE STRING "" FORCE)
91 FetchContent_MakeAvailable(freertos_kernel)
94 - In case of cross compilation, you should also add the following to `freertos_config`:
97 target_compile_definitions(freertos_config INTERFACE ${definitions})
98 target_compile_options(freertos_config INTERFACE ${options})
101 ### Consuming stand-alone - Cloning this repository
103 To clone using HTTPS:
106 git clone https://github.com/FreeRTOS/FreeRTOS-Kernel.git
112 git clone git@github.com:FreeRTOS/FreeRTOS-Kernel.git
115 ## Repository structure
117 - The root of this repository contains the three files that are common to
118 every port - list.c, queue.c and tasks.c. The kernel is contained within these
119 three files. croutine.c implements the optional co-routine functionality - which
120 is normally only used on very memory limited systems.
122 - The ```./portable``` directory contains the files that are specific to a particular microcontroller and/or compiler.
123 See the readme file in the ```./portable``` directory for more information.
125 - The ```./include``` directory contains the real time kernel header files.
127 - The ```./template_configuration``` directory contains a sample `FreeRTOSConfig.h` to help jumpstart a new project.
128 See the [FreeRTOSConfig.h](examples/template_configuration/FreeRTOSConfig.h) file for instructions.
132 FreeRTOS files are formatted using the
133 "[uncrustify](https://github.com/uncrustify/uncrustify)" tool.
134 The configuration file used by uncrustify can be found in the
135 [FreeRTOS/CI-CD-GitHub-Actions's](https://github.com/FreeRTOS/CI-CD-Github-Actions)
136 [uncrustify.cfg](https://github.com/FreeRTOS/CI-CD-Github-Actions/tree/main/formatting)
141 File checked into the FreeRTOS-Kernel repository use unix-style LF line endings
142 for the best compatibility with git.
144 For optimal compatibility with Microsoft Windows tools, it is best to enable
145 the git autocrlf feature. You can enable this setting for the current
146 repository using the following command:
149 git config core.autocrlf true
152 ### Git History Optimizations
154 Some commits in this repository perform large refactors which touch many lines
155 and lead to unwanted behavior when using the `git blame` command. You can
156 configure git to ignore the list of large refactor commits in this repository
157 with the following command:
160 git config blame.ignoreRevsFile .git-blame-ignore-revs
163 ### Spelling and Formatting
165 We recommend using [Visual Studio Code](https://code.visualstudio.com),
166 commonly referred to as VSCode, when working on the FreeRTOS-Kernel.
167 The FreeRTOS-Kernel also uses [cSpell](https://cspell.org/) as part of its
168 spelling check. The config file for which can be found at [cspell.config.yaml](cspell.config.yaml)
169 There is additionally a
170 [cSpell plugin for VSCode](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker)
171 that can be used as well.
172 *[.cSpellWords.txt](.github/.cSpellWords.txt)* contains words that are not
173 traditionally found in an English dictionary. It is used by the spellchecker
174 to verify the various jargon, variable names, and other odd words used in the
175 FreeRTOS code base are correct. If your pull request fails to pass the spelling
176 and you believe this is a mistake, then add the word to
177 *[.cSpellWords.txt](.github/.cSpellWords.txt)*. When adding a word please
178 then sort the list, which can be done by running the bash command:
179 `sort -u .cSpellWords.txt -o .cSpellWords.txt`
180 Note that only the FreeRTOS-Kernel Source Files, [include](include),
181 [portable/MemMang](portable/MemMang), and [portable/Common](portable/Common)
182 files are checked for proper spelling, and formatting at this time.
185 Visit [this link](.github/third_party_tools.md) for detailed information about
186 third-party tools with FreeRTOS support.