Enable clang-tidy checks and fix warnings in code

[elfenpiff]

Brief feature description

At the moment a lot of clang-tidy checks in our root .clang-tidy file are disabled to ensure that our codebase is at least warning free with a minimal subset of clang-tidy checks.

We should enable the disabled checks one by one and solve the generated warnings in the same step. Some of the warnings require a larger refactoring. If this happens please create another issue and add a todo link in this issue.

ToDo

1. Remove the compiler warning suppression from all tests, see CMakeLists.txt and the entry set(TEST_CXX_FLAGS PRIVATE ${ICEORYX_WARNINGS} ${ICEORYX_SANITIZER_FLAGS} -Wno-pedantic -Wno-conversion) and fix all warnings.
2. Create a .clang-tidy file in every test disables warning which originate from the googletest fixtures itself. For instance TEST_F and TYPED_TEST have a rule of 5 warning.

Hints

The .clang-tidy file may have warnings which do not fit for us. If this is the case then please disable the warning and write a justification why this is rule is not appropriate. Example:

* rule: readability-identifier-length
  justification: In some functions single letter variables make sense, this is covered by the review process
  example:
     bad:
       int sum(int summand1, int summand2); // here we would like to have single letter variable arguments
     good:
       int sum(int a, int b); // failure since a and b have less than three letters

CI checks

• iceoryx_hoofs diff checks
  • [x] cxx @elfenpiff
  • [ ] concurrent
  • [x] design_pattern @elfenpiff
  • [x] posix_wrapper @elfenpiff
  • [x] units @elfenpiff
• [x] iceoryx_hoofs full nightly scan based on .clang-tidy-diff-scans.txt @elfenpiff

Files

When a file is stated, it means the header, inline file, cpp file and also the tests are refined.

iceoryx_hoofs/cxx

• [x] adaptive_wait @elfenpiff
• [x] algorithm @elfenpiff
• [x] attributes.hpp @elfenpiff (muahahha there were no warnings but it still counts!)
• [x] convert @elfenpiff
• [x] deadline_timer @elfenpiff
• [x] expected @elfenpiff
• [x] file_reader @FerdinandSpitzschnueffler
• [x] filesystem @elfenpiff
• [x] forward_list @FerdinandSpitzschnueffler
• [x] function_ref @mossmaurice
• [x] function @elfenpiff
• [x] functional_interface @elfenpiff
• [x] generic_raii @elfenpiff
• [x] helplets @elfenpiff
• [x] list @elfenpiff
• [x] newtype @elBoberido
• [x] optional @FerdinandSpitzschnueffler
• [x] pair @elfenpiff
• [x] poor_mans_heap @elBoberido
• [x] reference_counter @elfenpiff
• [x] requires @elfenpiff
• [x] scoped_static @elfenpiff
• [x] serialization @elBoberido
• [x] set @elfenpiff
• [x] static_storage @elfenpiff
• [x] stack @elBoberido
• [x] storable_function @elfenpiff
• [x] string @FerdinandSpitzschnueffler
• [x] types @elBoberido
• [x] type_traits @elfenpiff
• [x] unique_id @elfenpiff
• [x] unique_ptr @mossmaurice
• [x] variant @mossmaurice
• [x] variant_queue @FerdinandSpitzschnueffler
• [x] vector @mossmaurice

iceoryx_hoofs/units

• [x] duration @elBoberido

iceoryx_hoofs/concurrent

• [x] lockfree_queue complete folder + header @MatthiasKillat
• [x] ~~active_object (ignore because it's obsolete?)~~
• [x] fifo @FerdinandSpitzschnueffler
• [x] loffli @FerdinandSpitzschnueffler
• [x] periodic_task @FerdinandSpitzschnueffler
• [x] smart_lock @FerdinandSpitzschnueffler
• [x] sofi @FerdinandSpitzschnueffler
• [x] taco @FerdinandSpitzschnueffler
• [x] trigger_queue (no warnings to fix)

iceoryx_hoofs/rp

• [x] PointerRepository @mossmaurice
• [x] RelativePointer @mossmaurice
• [x] BaseRelativePointer @mossmaurice
• [x] RelativePointerData @mossmaurice
• [x] relocatable_ptr @MatthiasKillat

posix_wrapper

• [x] shared_memory_object - complete folder @MatthiasKillat
• [x] access_control @elfenpiff
• [x] file_lock @elfenpiff
• [x] ipc_channel @elfenpiff
• [x] message_queue @elfenpiff
• [x] mutex @elfenpiff
• [x] named_pipe @elfenpiff
• [x] named_semaphore @elfenpiff
• [x] posix_access_rights @elfenpiff
• [x] posix_call @elfenpiff
• [x] semaphore_interface @elfenpiff
• [x] signal_handler @elfenpiff
• [x] signal_watcher @elfenpiff
• [x] system_configuration @FerdinandSpitzschnueffler
• [x] thread @FerdinandSpitzschnueffler
• [x] types @FerdinandSpitzschnueffler
• [x] unix_domain_socket @FerdinandSpitzschnueffler
• [x] unnamed_semaphore @elfenpiff

TODOs after merge of the integration branch

• [x] Setup CI job to run a space check // NOLINTNEXTLINE (
• [ ] improve readability of brance initialization by adding spaces between variable name, braces and values;

  // old
  int foo{42};
  // new
  int foo { 42 };
  

• [x] refactor operator<< in filesystem.cpp to reduce code complexity
• [ ] remove operator std::string() from cxx::string and implement toStdString method
• [ ] remove EXPECT_DEATH
• [ ] implement uninitialized array
• [ ] replace requires.hpp with error handler
• [ ] refactor cxx::convert to handle all cxx::string capacities
• [ ] remove suppressions in code base for rules that are disabled in clang-tidy file
• [ ] strerror_s handling. Is only added to windows but must be added to platform libc layer
• [ ] Seconds_t and Nanoseconds_t in duration should use Newtype pattern to parameter mixup

[elBoberido]

@elfenpiff convert is not done yet. clang-tidy does not report warnings because the hpp is not included in the inl. I uncheck the checkbox

[elBoberido]

@elfenpiff I would exclude log and error handler from clang-tidy checks. These will be refactored anyway and there is no need to waste time on it right now.