mirror of
https://github.com/zephyrproject-rtos/zephyr
synced 2025-09-01 03:45:55 +00:00
973487fdad
Add support for 64 bit conversions in a uniformly expressable way by printing values backwards into a buffer on the stack first. This allows all operations to work on the low bits of the value and so the code doesn't need to care (beyond the size of that buffer) about the word size. This trick also doesn't care about the specifics of the base value, so in the process this unifies the decimal and hex printk conversion code to a single function. This comes at a mild cost in CPU cycles to the decimal converter and somewhat higher cost to hex (because it's now doing a full div/mod operation instead of shifting and masking). And stack usage has grown by a few words to hold the temporary. But the benefits in code size are substantial (e.g. ~250 bytes of .text on arm32). Note that this also contains a change to tests/kernel/common to address what appears to have been a bug in the original converters. The printk test uses a format string that looks like "%-4x%-2p" and feeds it the literal arguments "0xABCDEF" and "(char *)42". Now... clearly both those results are going to overflow the 4 and 2-byte field sizes, so there shouldn't be any whitespace between these fields. But the test was written to expect two spaces, inexplicably (yes, I checked: POSIX-compatible printf implementations don't have those spaces either). The new code is definitely doing the right thing, so fix the test instead. Signed-off-by: Andy Ross <andrew.j.ross@intel.com> |
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| .buildkite | ||
| .github | ||
| .known-issues | ||
| arch | ||
| boards | ||
| cmake | ||
| doc | ||
| drivers | ||
| dts | ||
| include | ||
| kernel | ||
| lib | ||
| misc | ||
| modules | ||
| samples | ||
| scripts | ||
| share | ||
| soc | ||
| subsys | ||
| tests | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .codecov.yml | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| .gitlint | ||
| .mailmap | ||
| .shippable.yml | ||
| .uncrustify.cfg | ||
| CMakeLists.txt | ||
| CODE_OF_CONDUCT.md | ||
| CODEOWNERS | ||
| CONTRIBUTING.rst | ||
| Kconfig | ||
| Kconfig.zephyr | ||
| LICENSE | ||
| Makefile | ||
| README.rst | ||
| VERSION | ||
| version.h.in | ||
| west.yml | ||
| zephyr-env.cmd | ||
| zephyr-env.sh | ||
.. raw:: html
<a href="https://www.zephyrproject.org">
<p align="center">
<img src="doc/images/Zephyr-Project.png">
</p>
</a>
<a href="https://bestpractices.coreinfrastructure.org/projects/74"><img
src="https://bestpractices.coreinfrastructure.org/projects/74/badge"></a>
<img
src="https://api.shippable.com/projects/58ffb2b8baa5e307002e1d79/badge?branch=master">
The Zephyr Project is a scalable real-time operating system (RTOS) supporting
multiple hardware architectures, optimized for resource constrained devices,
and built with security in mind.
The Zephyr OS is based on a small-footprint kernel designed for use on
resource-constrained systems: from simple embedded environmental sensors and
LED wearables to sophisticated smart watches and IoT wireless gateways.
The Zephyr kernel supports multiple architectures, including ARM Cortex-M,
Intel x86, ARC, Nios II, Tensilica Xtensa, and RISC-V, and a large number of
`supported boards`_.
.. below included in doc/introduction/introduction.rst
.. start_include_here
Getting Started
***************
Welcome to Zephyr! See the `Introduction to Zephyr`_ for a high-level overview,
and the documentation's `Getting Started Guide`_ to start developing.
Community Support
*****************
Community support is provided via mailing lists and Slack; see the Resources
below for details.
.. _project-resources:
Resources
*********
Here's a quick summary of resources to help you find your way around:
* **Help**: `Asking for Help Tips`_
* **Documentation**: http://docs.zephyrproject.org (`Getting Started Guide`_)
* **Source Code**: https://github.com/zephyrproject-rtos/zephyr is the main
repository; https://elixir.bootlin.com/zephyr/latest/source contains a
searchable index
* **Releases**: https://github.com/zephyrproject-rtos/zephyr/releases
* **Samples and example code**: see `Sample and Demo Code Examples`_
* **Mailing Lists**: users@lists.zephyrproject.org and
devel@lists.zephyrproject.org are the main user and developer mailing lists,
respectively. You can join the developer's list and search its archives at
`Zephyr Development mailing list`_. The other `Zephyr mailing list
subgroups`_ have their own archives and sign-up pages.
* **Nightly CI Build Status**: https://lists.zephyrproject.org/g/builds
The builds@lists.zephyrproject.org mailing list archives the CI
(shippable) nightly build results.
* **Chat**: Zephyr's Slack workspace is https://zephyrproject.slack.com. Use
this `Slack Invite`_ to register.
* **Contributing**: see the `Contribution Guide`_
* **Wiki**: `Zephyr GitHub wiki`_
* **Issues**: https://github.com/zephyrproject-rtos/zephyr/issues
* **Security Issues**: Email vulnerabilities@zephyrproject.org to report
security issues; also see our `Security`_ documentation. Security issues are
tracked separately at https://zephyrprojectsec.atlassian.net.
* **Zephyr Project Website**: https://zephyrproject.org
.. _Slack Invite: https://tinyurl.com/y5glwylp
.. _supported boards: http://docs.zephyrproject.org/latest/boards/index.html
.. _Zephyr Documentation: http://docs.zephyrproject.org
.. _Introduction to Zephyr: http://docs.zephyrproject.org/latest/introduction/index.html
.. _Getting Started Guide: http://docs.zephyrproject.org/latest/getting_started/index.html
.. _Contribution Guide: http://docs.zephyrproject.org/latest/contribute/index.html
.. _Zephyr GitHub wiki: https://github.com/zephyrproject-rtos/zephyr/wiki
.. _Zephyr Development mailing list: https://lists.zephyrproject.org/g/devel
.. _Zephyr mailing list subgroups: https://lists.zephyrproject.org/g/main/subgroups
.. _Sample and Demo Code Examples: http://docs.zephyrproject.org/latest/samples/index.html
.. _Security: http://docs.zephyrproject.org/latest/security/index.html
.. _Asking for Help Tips: https://docs.zephyrproject.org/latest/guides/getting-help.html