Add .clang-format file

.clang-format

@@ -0,0 +1,49 @@
+---
+Language:        Cpp
+Standard:        Cpp11
+BasedOnStyle:  Chromium
+AccessModifierOffset: -2
+AlignAfterOpenBracket: DontAlign
+AllowShortFunctionsOnASingleLine: InlineOnly
+AllowShortIfStatementsOnASingleLine: false
+BinPackArguments: false
+BinPackParameters: false
+BraceWrapping:
+  AfterClass:      true
+  AfterControlStatement: true
+  AfterEnum:       true
+  AfterFunction:   true
+  AfterNamespace:  true
+  AfterObjCDeclaration: true
+  AfterStruct:     true
+  AfterUnion:      true
+  BeforeCatch:     true
+  BeforeElse:      true
+  SplitEmptyFunction: false
+BreakBeforeBraces: Custom
+BreakBeforeTernaryOperators: false
+BreakConstructorInitializers: BeforeColon
+BreakInheritanceList: AfterColon
+ColumnLimit:     100
+ConstructorInitializerIndentWidth: 2
+IncludeCategories:
+  - Regex:           '^".*'
+    Priority:        1
+  - Regex:           '^<boost.*'
+    Priority:        98
+  - Regex:           '^<.*\.h>'
+    Priority:        2
+  - Regex:           '^<.*'
+    Priority:        99
+  - Regex:           '.*'
+    Priority:        4
+IncludeIsMainRegex: '(Test)?$'
+IndentCaseLabels: false
+IndentWidth:     4
+ContinuationIndentWidth: 4
+MaxEmptyLinesToKeep: 2
+NamespaceIndentation: None
+PenaltyBreakAssignment: 1
+PenaltyBreakComment: 50
+TabWidth:        2
+...

circle.yml

@@ -35,6 +35,14 @@ defaults:
         sudo pip3 install codespell
         codespell --skip=".git"
 
+  clangformat: &clangformat
+    run:
+      name: "Run clang-format"
+      command: |
+        clang-format --version
+        find include src test -name '*.hpp' -o -name '*.cpp' -o -name '*.h' -o -name '*.c' | xargs clang-format -i
+        git diff --color --exit-code
+
   build: &build
     run:
       name: "Build"
@@ -325,6 +333,7 @@ jobs:
     steps:
       - checkout
       - *codespell
+      - *clangformat
 
   # The job collects built packages (available in the workspace) and
   # uploads them to the GitHub release matching the git tag.