FBSW-208 Moved common segment code for posix and file shm segments into ShmCommon

[guptask]

This change is 

[igchor]

Reviewable status: 0 of 4 files reviewed, 1 unresolved discussion (waiting on @guptask and @victoria-mcgrath)

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cachelib/shm/ShmCommon.cpp, line 166 at r1 (raw file):

    util::throwSystemError(errno, "invalid fd");
  }
  return fd;

Why did you remove the switch for errno? I think the behavior might be different after this change.

[guptask]

Reviewable status: 0 of 4 files reviewed, 1 unresolved discussion (waiting on @igchor and @victoria-mcgrath)

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cachelib/shm/ShmCommon.cpp, line 166 at r1 (raw file):

Previously, igchor (Igor Chorążewicz) wrote…

Why did you remove the switch for errno? I think the behavior might be different after this change.

Reverted to the errno switch case handling

[igchor]

, but I would like to wait with merging this until #6 and #2 (which contains some fixes for tests) is merged. it would be good to verify if all the tests are passing on CI for this change.

Reviewable status: 0 of 4 files reviewed, all discussions resolved (waiting on @victoria-mcgrath)

[igchor]

Reviewable status: 0 of 7 files reviewed, 2 unresolved discussions (waiting on @guptask and @victoria-mcgrath)

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cachelib/shm/FileShmSegment.cpp, line 219 at r4 (raw file):

int FileShmSegment::createNewSegment(const std::string& name) {
  constexpr static int createFlags = O_RDWR | O_CREAT | O_EXCL;

why you removed constexpr static?

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cachelib/shm/ShmCommon.h, line 47 at r4 (raw file):

};

// TODO(SHM_FILE): maybe we could use this inside the Tier Config class?

this should be removed

[victoria-mcgrath]

Reviewed 4 of 4 files at r2, 3 of 4 files at r4, 3 of 3 files at r5, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @guptask)

[igchor]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @guptask)