In commit 462b572172 the reading operation
on the PX4 side was changed to only read as many bytes as requested
rather than however many fit in the payload data.
This caused the unit tests to fail which this commit here aims to fix.
What is confusing about MAVLink FTP is that there is a size field which
generally signals how many bytes of the payload data are used/set.
However, in the case of a read requst, the size field is used to
indicate how many bytes should be read. The payload data is empty in
that case though.
This case was, from how I understand it, not implemented/tested in the
unit tests and now failed. In order to implement it I had to change a
few things:
- Change _setup_ftp_msg and _send_receive_msg so that the params contain
a data length rather than the size field. The size field itself needs
to be set outside of these methods using payload->size.
- Since we test files smaller, equal, and bigger than one payload data
length, I implemented that we send multiple read requests until we
have the whole file and not just the first part.
- Additionally, I saw a lot of uninitialized warnings in valgrind, and
got rid of them by adding a few zero initializations.
- mavlink/mavlink is now directly included as a submodule instead of the generated mavlink/c_library_v2
- this also switches to mavlink development.xml by default
I think it was not the best idea to use errno as a global variable to
keep track of the error code. I saw the errno change from where it was
set to where it was actually used, maybe because part of it is called in
the receive thread and part in the regular update/send() thread.
To be safe, I just created a class variable instead.
The MAVLink specs for CreateFile in MAVLink FTP were updated on Dec 23, 2020 (today) with a behavior change to truncate a file if it already existed, following the UNIX standard behavior: https://pubs.opengroup.org/onlinepubs/9699919799/functions/creat.html. This change is tracking that spec change. While it is a functional change, the limited usage of the FTP protocol and the fact that implementations should not rely on error states to determine wether to truncate a file or not makes this a viable change.
- change memory allocation from stack to a malloc'd buffer. This avoids
increasing the stack size. And since FTP is rarely used, the buffers
are only allocated upon use and freed after a time of 2s inactivity.
- adds PX4_ROOTFSDIR as root directory prefix. This does not change
anything on NuttX, but in SITL it will avoid enumerating the whole
disk tree when using QGC (which enumerates all files recursively).
The provided argument payload->offset is in range [0, num_file_entries-1],
but seekdir might use a completely different range. It is not defined
by the API spec. It is only useful in conjunction with telldir().
This was a real issue for long paths and not a flight safety issue for regular users, but could have been an issue for developers trying to use FTP on very deep nested file systems
Over time I made a few changes unrelated to what I'm really working on.
These changes are hereby committed first. The bug fixes are related to
what I'm doing in that I need them to be fixed for future commits.
Tools/sitl_run.sh: rename label to rcS_dir and fix usage help.
cmake/common/px4_base.cmake: Remove the check on OUT_UNPARSED_ARGUMENTS,
and a few typos and indentation issues.
cmake/configs/posix_sitl_replay.cmake: Set the correct variable
(config_sitl_rcS_dir) to the correct directory.
cmake/nuttx/px4_impl_nuttx.cmake: typos and indentation issues,
and removal of a redundant FORCE (INTERNAL implies FORCE).
cmake/posix/px4_impl_posix.cmake: typos and indentation issues.
cmake/qurt/px4_impl_qurt.cmake: typos and indentation issues.
src/modules/mavlink/mavlink_ftp.cpp : possible strict-aliasing breakage.
NOTES
The second argument passed to sitl_run.sh is the value of
config_sitl_rcS_dir. This fact is missing from the usage help.
I renamed 'label' to 'rcS_dir' to better reflect this.
Also, for the 'replay' config the wrong variable was set causing
the call to sitl_run.sh to skip an argument and fail (ie the
debugger was passed as rcS_dir and so on).
The check on OUT_UNPARSED_ARGUMENTS in px4_parse_function_args
basically causes every passed IN variable to be REQUIRED and is
therefore a bug. The test for the presence of the REQUIRED arguments
follows directly after and is sufficient for this job. This bug went
unnoticed because currently every argument to OPTIONS, ONE_VALUE,
and MULTI_VALUE is actually passed to the function(s) calling
px4_parse_function_args (them being REQUIRED or not).
The changes in mavlink_ftp.cpp are to avoid a possible aliasing bug
and (mostly) to avoid the compiler warning/error: dereferencing type-
punned pointer will break strict-aliasing rules [-Werror=strict-aliasing].
readdir_r is deprecated since glibc version 2.24 and glibc manual
recomends usage of readdir instead of readdir_r.
Replacing readdir_r by readdir will also not be a problem for Nuttx,
because readdir_r is using readdir and filling parameters with the
return information.
Signed-off-by: Otavio Pontes <otavio.pontes@intel.com>
In nuttx the mode parameter to open is not required but in Linux,
and per the POSIX spec, mode is required if the O_CREAT flag is
passed.
The mode flags are different for NuttX and Linux so a new set of
PX4 defines was added:
PX4_O_MODE_777 - read, write, execute for user, group and other
PX4_O_MODE_666 - read, and write for user, group and other
PX4_O_MODE_600 - read, and write for user
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Set a default path relative to current dir for the posix target.
Running make posixrun will create the required directoroes and then run
mainapp from its build location.
PX4_ROOTFSDIR is set to nothing for nuttx.
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Junwoo Hwang