Occasional crashes in Stream2 API

[MarkRivers]

I am seeing occasional crashed in the Stream2API when running on an Eiger2 9M. This is at the current master head, 0a5115e. This is a gdb trace when it happens:

Thread 20 "eigerStreamTask" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffef7f7640 (LWP 1484993)]
0x00007ffff5b9140d in __memmove_avx512_unaligned_erms () from /lib64/libc.so.6
(gdb) bt
#0  0x00007ffff5b9140d in __memmove_avx512_unaligned_erms () from /lib64/libc.so.6
#1  0x00007ffff7f90c1f in Stream2API::getFrame (this=0x7fffdc009960, pArrayOut=pArrayOut@entry=0x7fffef7f69b8, pNDArrayPool=<optimized out>,
    thresh=thresh@entry=0, decompress=0, extractTimeStamp=<optimized out>) at ../stream2Api.cpp:327
#2  0x00007ffff7f825f9 in eigerDetector::streamTask (this=0x5745a0) at ../eigerDetector.cpp:1500
#3  0x00007ffff63acf05 in start_routine (arg=0x5cfe80) at ../osi/os/posix/osdThread.c:444
#4  0x00007ffff5a8b2ea in start_thread () from /lib64/libc.so.6
#5  0x00007ffff5b103d0 in clone3 () from /lib64/libc.so.6

The crash is happening on this line:

ADEiger/eigerApp/src/stream2Api.cpp

Line 327 in 0a5115e

memcpy(pArray->pData, pInput, compressedSize);

Need to determine whether the problem is with pInput, compressedSize, etc.

[jwlodek]

We discovered what we think is the cause at the collaboration meeting today. Essentially, when parsing the ZMQ message into a stream2 frame, the pointer to the raw data is copied, not the underlying data itself:

ADEiger/eigerApp/src/stream2.c

Line 278 in 0a5115e

return consume_byte_string_nocopy(it, &bytes->ptr, &bytes->len, it);

. In #104 , we free'd the zmq message after it has been parsed into a stream2 frame. We believe the reason the issue is intermittent is because the underlying memory isn't always immediately re-used by the OS. The solution would be to move the zmq message free to after the stream2_frame free.

[MarkRivers]

I fixed this issue and tested it today. I will submit a PR soon.