Extend the logger to support coloring messages. The log level is
colorized with per-level colors, and the category with a fixed color.
This makes the log output more readable.
Coloring is enabled by default when logging to std::cerr, and can be
disabled by setting the LIBCAMERA_LOG_NO_COLOR environment variable.
When logging to a file with LIBCAMERA_LOG_FILE, coloring is disabled. It
can be enabled for file logging using the logSetFile() function.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
If the log file specified through LIBCAMERA_LOG_FILE can't be opened,
logging is currently completely disabled. This doesn't match the
documented behaviour that tells std::cerr is used instead. Fix it to
match the documentation.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
While std::cerr and stderr both target the same file by default, this
may be overridden by applications. Update the documentation to use
std::cerr instead of stderr to be accurate.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Create a new class to abstract generation and access to call stack
backtraces. The current implementation depends on the glibc backtrace()
implementation and is copied from the logger. Future development will
bring support for libunwind, transparently for the users of the class.
The logger backtrace implementation is dropped, replaced by usage of the
new Backtrace class.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
libcamera isn't supposed to log messages after the logger is destroyed,
as the global logger instance is destroyed after the main() function
returns, and the camera manager is supposed to have been stopped and
destroyed before that.
This rule is difficult to enforce in the V4L2 compat implementation, as
there is no location where we can destroy the camera manager manually
before the logger is destroyed. This results in a use-after-free
condition when the camera manager gets stopped during destruction.
Fix it by not trying to print log messages when the global logger
instance has been destroyed.
This is a bit of a hack, but hopefully not too bad. There could be race
conditions when using a CameraManager instance that is destroyed as part
of the destruction of global variables (like the V4L2 compat layer does,
it wraps CameraManager in a singleton V4L2CompatManager class, and
destroys it when V4L2CompatManager is destroyed) as the CameraManager
thread will still be running when the logger gets destroyed, but this
doesn't cause any regression as we destroy the logger without any
safeguard measure today anyway.
There are other options that could be considered. Forcing destruction of
the logger after the camera manager in the V4L2 compat layer is one of
them, but turned out to be difficult. For instance care would need to be
taken *not* to log any message in the mmap() wrapper if the fd doesn't
match a wrapped camera, as mmap() is called very early in the
initialization process, before libcamera and the logger get initialized.
The resulting implementation would likely be fairly complex.
Another option could be to wrap the logger with a shared pointer, and
keep a reference to it in CameraManager. That's more intrusive, and it's
not clear if it would be worth it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Usage of 'method' to refer to member functions comes from Java. The C++
standard uses the term 'function' only. Replace 'method' with 'function'
or 'member function' through the whole code base and documentation.
While at it, fix two typos (s/backeng/backend/).
The BoundMethod and Object::invokeMethod() are left as-is here, and will
be addressed separately.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Acked-by: Kieran Bingham <kieran.bingham@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>
