Parse ASCII Output of a Device-File in C++ - c++

Question

i wrote a kernelspace driver for a USB-device. If it is connected it mounts to /dev/myusbdev0 for example.
Via command line with echo -en "command" > /dev/myusbdev0 i can send commands to the device and read results with cat /dev/myusbdev0.
Ok, now i have to write a C++ program. At first i would open the device file for read/write with:
int fd = open("/dev/echo", O_RDRW);
After that a cmd will be send to get the device working:
char cmd[] = { "\x02sEN LMDscandata 1\x03" };
write(fd, cmd, sizeof(cmd));
Now i get to the part i dont now how to handle yet. i now need to read from the device, as its keeping on sending me data continously. this data i need to read and parse now ...
char buf[512];
read(fd, buf, sizeof(buf);
The data looks like following, each one starts with \x02 and ends with \x03, they are not always the same size:
sRA LMDscandata 1 1 89A27F 0 0 343 347 27477BA9 2747813B 0 0 7 0 0
1388 168 0 1 DIST1 3F800000 00000000 186A0 1388 15 8A1 8A5 8AB 8AC 8A6
8AC 8B6 8C8 8C2 8C9 8CB 8C4 8E4 8E1 8EB 8E0 8F5 908 8FC 907 906 0 0 0
0 0 0 All Values are separated with a 20hex {SPC}
it think i need some kind of while loop to continiously read the data from an \x02 until i read a \x03.
if i have a complete scan, i need to parse this ascii message in its seperate parts (some variables uint_16, uint_8, enum_16, ...).
any idea how i can read a complete scan into a buf[] and then parse its components out?

Answer 1

As you say the device is sending continiously, i would recommend adding a queue to hold the chunks coming in, and some dispatching that takes out parts of the queue, i.e. x02 to x03, decoupling the work that is done from receiving chunks.
Furthermore you can have then single objects handling one complete block from x02 to x03, perhaps threaded (makes sense with the information given).
device => chunk reader => input queue => inputer reader => data handling
hope this helps