init is the program responsible to set up userspace - mount filesystems, start services and reap process that die.
Some features that this init implementation provide (or intends to provide, see TODO):
- Processes can be started in a specific order;
- Processes can be deemed safe; special track of them is
provided, such as the ability to start a "safe-mode" application in
case it crashes;
- Process can be tied to a specific processor core;
- Simple [inittab](specs/inittab-spec.txt) file to define process;
- Follow [MISRA-C](https://www.misra.org.uk/MISRAHome/MISRAC2012/tabid/196/Default.aspx) guidelines to enhance safety of code;
- Thorough testing - coverage guided and providing mocks to test
error handling code.
u-nit requires glibc >= 2.9 and a Linux environment because it uses
Linux-specific functions. Other than that, a simple make should
build and generate init executable.
Automatic tests are provided on the tests directory. They can be invoked from Makefile. Some tests require QEMU - as well as a kernel and some root filesystems (not provided). See tests README for more information.
Code should be compliant with MISRA-C guidelines. Note however that not all guidelines are being strictly followed right now: it is still being evaluated which guidelines will be followed and which will be deviated. In this case, a formal deviation process will be followed.
Regarding code-style, u-nit loosely follows Linux kernel
guidelines. clang-format
is used to enforce code style. Simply run make format-code and the code
will be formatted accordingly.
By making a contribution to this project, I certify that:
(a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or
(b) The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or
(c) The contribution was provided directly to me by some other person who certified (a), (b) or (c) and I have not modified it.
(d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved.
Please report any security issues with this code to https://01.org/security
The software may be used to create end products used in safety-critical applications designed to comply with functional safety standards or requirements (“Safety-Critical Applications”), however, it may not be qualified for use in all applications in which its failure could create a safety hazard or any situation where personal injury or death may occur, including but not limited to medical, life-saving or life sustaining systems, transportation systems, manned or unmanned vehicles, nuclear systems, or in combination with any potentially hazardous product. It is licensee’s responsibility to design, manage and assure system-level safeguards to anticipate, monitor and control system failures, and licensee is solely responsible for all applicable regulatory standards and safety-related requirements concerning licensee’s use of the software in Safety Critical Applications.