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
  • cxx @elfenpiff
  • concurrent @elfenpiff
  • design_pattern @elfenpiff
  • posix_wrapper @elfenpiff
  • units @elfenpiff
• 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

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

iceoryx_hoofs/units

• duration @elBoberido

iceoryx_hoofs/concurrent

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

iceoryx_hoofs/rp

• PointerRepository @mossmaurice
• RelativePointer @mossmaurice
• BaseRelativePointer @mossmaurice
• RelativePointerData @mossmaurice
• relocatable_ptr @MatthiasKillat

posix_wrapper

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

TODOs after merge of the integration branch

• Setup CI job to run a space check // NOLINTNEXTLINE (
• Tracked here: Improve readability of brace initialization by adding spaces #1611 improve readability of brance initialization by adding spaces between variable name, braces and values;

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

• refactor operator<< in filesystem.cpp to reduce code complexity
• Tracked here: Replace operator std::string() with toStdString() method #1612 remove operator std::string() from cxx::string and implement toStdString method
• Tracked here: Remove EXPECT_DEATH #1613 remove EXPECT_DEATH
• Tracked here: implement uninitialized array #1614 implement uninitialized array
• Tracked as todo in: ErrorHandling concept with user defined actions #1032 replace requires.hpp with error handler
• Tracked as todo in: Clean-up string usage #260 refactor cxx::convert to handle all cxx::string capacities
• Tracked here: Cleanup superfluous clang-tidy suppressions #1615 remove suppressions in code base for rules that are disabled in clang-tidy file
• Tracked here: Handle 'strerror_r' idiosyncrasies in the platform layer #1616 strerror_s handling. Is only added to windows but must be added to platform libc layer
• Tracked here: Use newtype pattern to solve parameter mixup #1617 Seconds_t and Nanoseconds_t in duration should use Newtype pattern to parameter mixup