Problem: code duplication and unnecessary nesting around ZMQ_THREAD_SAFE querying

.clang-format

@@ -0,0 +1,53 @@
+BasedOnStyle: LLVM
+IndentWidth: 4
+UseTab: Never
+BreakBeforeBraces: Custom
+BraceWrapping: 
+    AfterClass: true
+    AfterControlStatement: false
+    AfterEnum: true 
+    AfterFunction: true 
+    AfterNamespace: true
+    AfterObjCDeclaration: true 
+    AfterStruct: true 
+    AfterUnion: true 
+    BeforeCatch: true 
+    BeforeElse: false 
+    IndentBraces: false
+
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AllowShortIfStatementsOnASingleLine: false
+IndentCaseLabels: true
+BinPackArguments: true
+BinPackParameters: false
+AlignTrailingComments: true
+AllowShortBlocksOnASingleLine: false
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortFunctionsOnASingleLine: InlineOnly
+AlwaysBreakTemplateDeclarations: false
+ColumnLimit: 80
+MaxEmptyLinesToKeep: 2
+KeepEmptyLinesAtTheStartOfBlocks: false
+ContinuationIndentWidth: 2
+PointerAlignment: Right
+ReflowComments: false
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeParens: Always
+SpaceInEmptyParentheses: false
+SpacesInAngles: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard: Cpp11
+
+SortIncludes: false
+
+FixNamespaceComments: false
+BreakBeforeBinaryOperators: NonAssignment
+SpaceAfterTemplateKeyword: true
+AlignAfterOpenBracket: Align
+AlignOperands: true
+BreakConstructorInitializers: AfterColon
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+SpaceAfterCStyleCast: true
+BreakBeforeTernaryOperators: true

.travis.yml

@@ -84,6 +84,14 @@ matrix:
   - env: BUILD_TYPE=android CURVE=tweetnacl
     os: linux
     dist: trusty
+  - env: BUILD_TYPE=cmake DO_CLANG_FORMAT_CHECK=1 CLANG_FORMAT=/usr/local/clang-5.0.0/bin/clang-format
+    os: linux
+    addons:
+    apt:
+      sources:
+        - llvm-toolchain-trusty-5.0
+      packages:
+        - clang-5.0
 
 sudo: required
 

CMakeLists.txt

@@ -1070,7 +1070,7 @@ if (MSVC AND ENABLE_CPACK)
   # add_crt_version (v100)
   # add_crt_version (v90)
 
-  set (CMAKE_MODULE_PATH "${CMAKE_CURRENT_BINARY_DIR}")
+  list (APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_BINARY_DIR})
   set (CPACK_GENERATOR "NSIS")
   set (CPACK_PACKAGE_NAME "ZeroMQ")
   set (CPACK_PACKAGE_DESCRIPTION_SUMMARY "ZeroMQ lightweight messaging kernel")
@@ -1138,3 +1138,5 @@ if (MSVC_VERSION EQUAL 1600)
     file (APPEND "${ZMQ_SLN_FILENAME}" "\n# This should be regenerated!\n")
   endif ()
 endif ()
+
+include(ClangFormat)

builds/cmake/Modules/ClangFormat.cmake

@@ -0,0 +1,41 @@
+# additional target to perform clang-format run, requires clang-format
+
+# get all project files
+file(GLOB_RECURSE ALL_SOURCE_FILES 
+     RELATIVE ${CMAKE_CURRENT_BINARY_DIR} 
+     ${CMAKE_SOURCE_DIR}/src/*.cpp ${CMAKE_SOURCE_DIR}/src/*.h ${CMAKE_SOURCE_DIR}/src/*.hpp 
+     ${CMAKE_SOURCE_DIR}/tests/*.cpp ${CMAKE_SOURCE_DIR}/tests/*.h ${CMAKE_SOURCE_DIR}/tests/*.hpp 
+     ${CMAKE_SOURCE_DIR}/perf/*.cpp ${CMAKE_SOURCE_DIR}/perf/*.h ${CMAKE_SOURCE_DIR}/perf/*.hpp 
+     ${CMAKE_SOURCE_DIR}/tools/*.cpp ${CMAKE_SOURCE_DIR}/tools/*.h ${CMAKE_SOURCE_DIR}/tools/*.hpp 
+     ${CMAKE_SOURCE_DIR}/include/*.h
+    )
+
+if("${CLANG_FORMAT}" STREQUAL "")
+  set(CLANG_FORMAT "clang-format")
+endif()
+
+add_custom_target(
+        clang-format
+        COMMAND ${CLANG_FORMAT} -style=file -i ${ALL_SOURCE_FILES}
+)
+
+function(JOIN VALUES GLUE OUTPUT)
+  string (REPLACE ";" "${GLUE}" _TMP_STR "${VALUES}")
+  set (${OUTPUT} "${_TMP_STR}" PARENT_SCOPE)
+endfunction()
+
+configure_file(builds/cmake/clang-format-check.sh.in clang-format-check.sh @ONLY)
+
+add_custom_target(
+        clang-format-check
+        COMMAND chmod +x clang-format-check.sh
+        COMMAND ./clang-format-check.sh
+        COMMENT "Checking correct formatting according to .clang-format file using ${CLANG_FORMAT}"
+)
+
+add_custom_target(
+        clang-format-diff
+        COMMAND ${CLANG_FORMAT} -style=file -i ${ALL_SOURCE_FILES}
+        COMMAND git diff ${ALL_SOURCE_FILES}
+        COMMENT "Formatting with clang-format (using ${CLANG_FORMAT}) and showing differences with latest commit"
+)

builds/cmake/ci_build.sh

@@ -18,6 +18,10 @@ CMAKE_OPTS+=("-DCMAKE_PREFIX_PATH:PATH=${BUILD_PREFIX}")
 CMAKE_OPTS+=("-DCMAKE_LIBRARY_PATH:PATH=${BUILD_PREFIX}/lib")
 CMAKE_OPTS+=("-DCMAKE_INCLUDE_PATH:PATH=${BUILD_PREFIX}/include")
 
+if [ "$CLANG_FORMAT" != "" ] ; then
+    CMAKE_OPTS+=("-DCLANG_FORMAT=${CLANG_FORMAT}")
+fi
+
 if [ -z $CURVE ]; then
     CMAKE_OPTS+=("-DENABLE_CURVE=OFF")
 elif [ $CURVE == "libsodium" ]; then
@@ -31,4 +35,14 @@ elif [ $CURVE == "libsodium" ]; then
 fi
 
 # Build, check, and install from local source
-( cd ../..; mkdir build_cmake && cd build_cmake && PKG_CONFIG_PATH=${BUILD_PREFIX}/lib/pkgconfig cmake "${CMAKE_OPTS[@]}" .. && make -j5 all VERBOSE=1 && make install && make -j5 test ) || exit 1
+cd ../..
+mkdir build_cmake
+cd build_cmake
+if [ "$DO_CLANG_FORMAT_CHECK" -eq "1" ] ; then
+    if ! ( PKG_CONFIG_PATH=${BUILD_PREFIX}/lib/pkgconfig cmake "${CMAKE_OPTS[@]}" .. && make clang-format-check) ; then
+        make clang-format-diff
+        exit 1
+    fi
+else
+    ( PKG_CONFIG_PATH=${BUILD_PREFIX}/lib/pkgconfig cmake "${CMAKE_OPTS[@]}" .. && make -j5 all VERBOSE=1 && make install && make -j5 test ) || exit 1
+fi

builds/cmake/clang-format-check.sh.in

@@ -0,0 +1,14 @@
+#!/bin/sh
+FAILED=0
+IFS=";"
+FILES="@ALL_SOURCE_FILES@"
+IDS=$(echo -en "\n\b")
+for FILE in $FILES
+do
+	@CLANG_FORMAT@ -style=file -output-replacements-xml "$FILE" | grep "<replacement " >/dev/null &&
+    {
+      echo "$FILE is not correctly formatted"
+	  FAILED=1
+	}
+done
+if [ "$FAILED" -eq "1" ] ; then exit 1 ; fi