This is to avoid blocking in any case.
If we don't do that, ioctl() may signal data available while the other
protocol does a read(), and when the first protocol tries to do a read(),
it would not have data anymore and would block (so this avoids a race
condition).
This is an attempt to implement the protocol_splitter with one
read buffer only. The idea is to prevent additional copy
operations from an incoming buffer to the respective protocol buffer.
Right now the benefit is not really there because we are not using a
ringbuffer and have to shift data around quite a bit.
We also try to parse and copy data to the reader immediately without
doing a read from the device which potentially takes 100ms.
We further use a timeout mechanism to prevent starvation if one reader
disconnects and the buffer would fill up from unread data.
and remove the px4_ prefix, except for px4_config.h.
command to update includes:
for k in app.h atomic.h cli.h console_buffer.h defines.h getopt.h i2c.h init.h log.h micro_hal.h module.h module_params.h param.h param_macros.h posix.h sem.h sem.hpp shmem.h shutdown.h tasks.h time.h workqueue.h; do for i in $(grep -rl 'include <px4_'$k src platforms boards); do sed -i 's/#include <px4_'$k'/#include <px4_platform_common\/'$k/ $i; done; done
for in $(grep -rl 'include <px4_config.h' src platforms boards); do sed -i 's/#include <px4_config.h/#include <px4_platform_common\/px4_config.h'/ $i; done
Transitional headers for submodules are added (px4_{defines,log,time}.h)
Beat Küng