This implements a file descriptor used for event notification that
behaves like the eventfd in Linux.
The eventfd supports nonblocking operation by setting the EFD_NONBLOCK
flag and semaphore operation by settings the EFD_SEMAPHORE flag.
The major use case for this is when using poll() and the sockets that
you poll are dynamic. When a new socket needs to be added to the poll,
there must be some way to wake the thread and update the pollfds before
calling poll again. One way to solve it is to have a timeout set in the
poll call and only update the pollfds during a timeout but that is not
a very nice solution. By instead including an eventfd in the pollfds,
it is possible to wake the polling thread by simply writing to the
eventfd.
Signed-off-by: Tobias Svehagen <tobias.svehagen@gmail.com>
This commit refactors kernel and arch headers to establish a boundary
between private and public interface headers.
The refactoring strategy used in this commit is detailed in the issue
This commit introduces the following major changes:
1. Establish a clear boundary between private and public headers by
removing "kernel/include" and "arch/*/include" from the global
include paths. Ideally, only kernel/ and arch/*/ source files should
reference the headers in these directories. If these headers must be
used by a component, these include paths shall be manually added to
the CMakeLists.txt file of the component. This is intended to
discourage applications from including private kernel and arch
headers either knowingly and unknowingly.
- kernel/include/ (PRIVATE)
This directory contains the private headers that provide private
kernel definitions which should not be visible outside the kernel
and arch source code. All public kernel definitions must be added
to an appropriate header located under include/.
- arch/*/include/ (PRIVATE)
This directory contains the private headers that provide private
architecture-specific definitions which should not be visible
outside the arch and kernel source code. All public architecture-
specific definitions must be added to an appropriate header located
under include/arch/*/.
- include/ AND include/sys/ (PUBLIC)
This directory contains the public headers that provide public
kernel definitions which can be referenced by both kernel and
application code.
- include/arch/*/ (PUBLIC)
This directory contains the public headers that provide public
architecture-specific definitions which can be referenced by both
kernel and application code.
2. Split arch_interface.h into "kernel-to-arch interface" and "public
arch interface" divisions.
- kernel/include/kernel_arch_interface.h
* provides private "kernel-to-arch interface" definition.
* includes arch/*/include/kernel_arch_func.h to ensure that the
interface function implementations are always available.
* includes sys/arch_interface.h so that public arch interface
definitions are automatically included when including this file.
- arch/*/include/kernel_arch_func.h
* provides architecture-specific "kernel-to-arch interface"
implementation.
* only the functions that will be used in kernel and arch source
files are defined here.
- include/sys/arch_interface.h
* provides "public arch interface" definition.
* includes include/arch/arch_inlines.h to ensure that the
architecture-specific public inline interface function
implementations are always available.
- include/arch/arch_inlines.h
* includes architecture-specific arch_inlines.h in
include/arch/*/arch_inline.h.
- include/arch/*/arch_inline.h
* provides architecture-specific "public arch interface" inline
function implementation.
* supersedes include/sys/arch_inline.h.
3. Refactor kernel and the existing architecture implementations.
- Remove circular dependency of kernel and arch headers. The
following general rules should be observed:
* Never include any private headers from public headers
* Never include kernel_internal.h in kernel_arch_data.h
* Always include kernel_arch_data.h from kernel_arch_func.h
* Never include kernel.h from kernel_struct.h either directly or
indirectly. Only add the kernel structures that must be referenced
from public arch headers in this file.
- Relocate syscall_handler.h to include/ so it can be used in the
public code. This is necessary because many user-mode public codes
reference the functions defined in this header.
- Relocate kernel_arch_thread.h to include/arch/*/thread.h. This is
necessary to provide architecture-specific thread definition for
'struct k_thread' in kernel.h.
- Remove any private header dependencies from public headers using
the following methods:
* If dependency is not required, simply omit
* If dependency is required,
- Relocate a portion of the required dependencies from the
private header to an appropriate public header OR
- Relocate the required private header to make it public.
This commit supersedes #20047, addresses #19666, and fixes#3056.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
Stop linking interface libraries against zephyr_interface. This is
cargo cult code that in practice does nothing.
Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
Allow to enable individual POSIX components, like Pthreads.
CONFIG_POSIX_API now just enables all of individual POSIX components,
and sets up environment suitable to easily port POSIX applications to
Zephyr.
Fixes: #12965
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Similar to how other sub-libraries are defined in Zephyr tree, e.g.
"fs", "lgvl", etc. This is supposed to help with the need to
explicitly add posix include path to each and every application using
POSIX subsys.
Fixes: #15627
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Historically, it used to be "PTHREAD", which is no longer true, as
POSIX subsys offers much more functionality than just Pthreads. Use
detailed name, like "posix_subsys", to avoid possible confusion with
ARCH_POSIX-related matters.
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Update the files which contain no license information with the
'Apache-2.0' SPDX license identifier. Many source files in the tree are
missing licensing information, which makes it harder for compliance
tools to determine the correct license.
By default all files without license information are under the default
license of Zephyr, which is Apache version 2.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Added 4 new pthread_key APIs for thread-specific data
key creation, deletion, setting and getting the values.
Added a key list to the posix_struct for threads.
Added pthread_once API.
Signed-off-by: Niranjhana N <niranjhana.n@intel.com>
Both variables were used (with the same value) interchangeably
throughout CMake files and per the discussion in GH issue,
ZEPHYR_BASE is preferred.
Also add a comment with explanation of one vs. the other.
Tested by building hello_world for several boards ensuring no errors.
Fixes#7173.
Signed-off-by: Alex Tereschenko <alext.mkrs@gmail.com>
Add IEEE 1003.1 Posix Style file system API support.
These API's will internally use corresponding Zephyr
File System API's.
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Move posix layer from 'kernel' to 'lib' folder as it is not
a core kernel feature.
Fixed posix header file dependencies as part of the move and
also removed NEWLIBC related macros from posix headers.
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
