The `ProcessManager` is a singleton class to handle `SIGCHLD` signals
and report the exit status to the particular `Process` instance.
However, having a singleton in a library is not favourable and it is
even less favourable if it installs a signal handler.
Using pidfd it is possible to avoid the need for the signal handler;
and the `Process` objects can watch their pidfd themselves, eliminating
the need for the `ProcessManager` class altogether.
`P_PIDFD` for `waitid()` was introduced in Linux 5.4, so this change
raises the minimum supported kernel version. `clone3()`, `CLONE_PIDFD`,
`pidfd_send_signal()` were all introduced earlier.
Furthermore, the call to the `unshare()` system call can be removed
as those options can be passed to `clone3()` directly.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Instead of creating a new vector, take the vector by value to make it
possible for the caller to use move construction when calling the function.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Instead of using a separate member variable, use `pid_ > 0` to determine
if the process is still running. Previously the value of `pid_` was not
reset to -1 when the process terminated, but since it is only meaningful
while the process is running, reset it to -1 in `Process::died()`.
Neither `pid_` nor `running_` are exposed, so this change has no effect
on the public interface or observable behaviour.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
A `Process` object has address identity because a pointer to it is
stored inside the `ProcessManager`. However, copy/move special
methods are still generated by the compiler. So disable them to
avoid potential issues and confusion.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Source files in libcamera start by a comment block header, which
includes the file name and a one-line description of the file contents.
While the latter is useful to get a quick overview of the file contents
at a glance, the former is mostly a source of inconvenience. The name in
the comments can easily get out of sync with the file name when files
are renamed, and copy & paste during development have often lead to
incorrect names being used to start with.
Readers of the source code are expected to know which file they're
looking it. Drop the file name from the header comment block.
The change was generated with the following script:
----------------------------------------
dirs="include/libcamera src test utils"
declare -rA patterns=(
['c']=' \* '
['cpp']=' \* '
['h']=' \* '
['py']='# '
['sh']='# '
)
for ext in ${!patterns[@]} ; do
files=$(for dir in $dirs ; do find $dir -name "*.${ext}" ; done)
pattern=${patterns[${ext}]}
for file in $files ; do
name=$(basename ${file})
sed -i "s/^\(${pattern}\)${name} - /\1/" "$file"
done
done
----------------------------------------
This misses several files that are out of sync with the comment block
header. Those will be addressed separately and manually.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Remove the verbose #ifndef/#define/#endif pattern for maintaining
header idempotency, and replace it with a simple #pragma once.
This simplifies the headers, and prevents redundant changes when
header files get moved.
Tracepoints.h.in is not modified to use the pragma as it requires
self-inclusion.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Many signals used in internal and public APIs carry the emitter pointer
as a signal argument. This was done to allow slots connected to multiple
signal instances to differentiate between emitters. While starting from
a good intention of facilitating the implementation of slots, it turned
out to be a bad API design as the signal isn't meant to know what it
will be connected to, and thus shouldn't carry parameters that are
solely meant to support a use case specific to the connected slot.
These pointers turn out to be unused in all slots but one. In the only
case where it is needed, it can be obtained by wrapping the slot in a
lambda function when connecting the signal. Do so, and drop the emitter
pointer from all signals.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Move the functionality for the following components to the new
base support library:
- BoundMethod
- EventDispatcher
- EventDispatcherPoll
- Log
- Message
- Object
- Signal
- Semaphore
- Thread
- Timer
While it would be preferable to see these split to move one component
per commit, these components are all interdependent upon each other,
which leaves us with one big change performing the move for all of them.
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
If any Process instances are destroyed after the ProcessManager is
destroyed, then a segfault will occur.
Fix this by making the lifetime of the ProcessManager explicit, and make
the CameraManager construct and deconstruct (automatically, via a member
variable) the ProcessManager.
Update the tests accordingly.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
The ipc_unixsocket.h and process.h internal headers don't need to
include event_notifier.h, the former because a forward declaration
suffices, and the latter because it doesn't use event notifiers. Remove
the unnecessary include, and include signal.h instead which is required
and was included indirectly through event_notifier.h.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
With the internal headers now in include/libcamera/internal/, we may
have identically named headers in include/libcamera/. Their header
guards would clash. Rename the header guards of internal headers to
prevent any issue.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
The libcamera internal headers are located in src/libcamera/include/.
The directory is added to the compiler headers search path with a meson
include_directories() directive, and internal headers are included with
(e.g. for the internal semaphore.h header)
#include "semaphore.h"
All was well, until libcxx decided to implement the C++20
synchronization library. The __threading_support header gained a
#include <semaphore.h>
to include the pthread's semaphore support. As include_directories()
adds src/libcamera/include/ to the compiler search path with -I, the
internal semaphore.h is included instead of the pthread version.
Needless to say, the compiler isn't happy.
Three options have been considered to fix this issue:
- Use -iquote instead of -I. The -iquote option instructs gcc to only
consider the header search path for headers included with the ""
version. Meson unfortunately doesn't support this option.
- Rename the internal semaphore.h header. This was deemed to be the
beginning of a long whack-a-mole game, where namespace clashes with
system libraries would appear over time (possibly dependent on
particular system configurations) and would need to be constantly
fixed.
- Move the internal headers to another directory to create a unique
namespace through path components. This causes lots of churn in all
the existing source files through the all project.
The first option would be best, but isn't available to us due to missing
support in meson. Even if -iquote support was added, we would need to
fix the problem before a new version of meson containing the required
support would be released.
The third option is thus the only practical solution available. Bite the
bullet, and do it, moving headers to include/libcamera/internal/.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Jacopo Mondi <jacopo@jmondi.org>
