Format native code using clang-format (#2101)

.clang-format

@@ -1,3 +1,81 @@
 ---
-# We'll use defaults from the LLVM style, but with 4 columns indentation.
-BasedOnStyle: Google
+# copied from: https://github.com/dotnet/runtime/blob/main/src/coreclr/jit/.clang-format
+Language:     Cpp
+AccessModifierOffset: -4
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: true
+AlignConsecutiveDeclarations: true
+AlignEscapedNewlinesLeft: false
+AlignOperands:   true
+AlignTrailingComments: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: true
+BinPackArguments: true
+BinPackParameters: false
+BraceWrapping:
+  AfterClass:      true
+  AfterControlStatement: true
+  AfterEnum:       false
+  AfterFunction:   true
+  AfterNamespace:  false
+  AfterObjCDeclaration: false
+  AfterStruct:     true
+  AfterUnion:      true
+  BeforeCatch:     true
+  BeforeElse:      true
+  IndentBraces:    false
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Allman
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: true
+ColumnLimit:   120
+CommentPragmas:  '^ IWYU pragma:'
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+Cpp11BracedListStyle: true
+DerivePointerAlignment: false
+DisableFormat:   false
+ExperimentalAutoDetectBinPacking: false
+ForEachMacros:   [  ]
+IndentCaseLabels: true
+IndentWidth:     4
+IndentWrappedFunctionNames: false
+KeepEmptyLinesAtTheStartOfBlocks: true
+MacroBlockBegin: ''
+MacroBlockEnd:   ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBlockIndentWidth: 2
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakBeforeFirstCallParameter: 400
+PenaltyBreakComment: 50
+PenaltyBreakFirstLessLess: 500
+PenaltyBreakString: 1000
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 100000
+PointerAlignment: Left
+ReflowComments:  true
+SortIncludes:    false
+SpaceAfterCStyleCast: false
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeParens: ControlStatements
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles:  false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard:        Cpp11
+TabWidth:        4
+UseTab:          Never
+...

.github/workflows/dotnet-format.yml

@@ -11,6 +11,7 @@ on:
     paths:
     - '**.cs'
     - '.editorconfig'
+  workflow_dispatch:
 
 jobs:
   check-format:

.github/workflows/format-native.yml

@@ -0,0 +1,26 @@
+name: format native
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  check-native-format:
+    strategy:
+      fail-fast: false
+      matrix:
+        machine: [ windows-2022, ubuntu-20.04, macos-11 ]
+    runs-on: ${{ matrix.machine }}
+
+    steps:
+    - uses: actions/checkout@v3.3.0
+
+    - name: Install Clang tools
+      shell: bash
+      run: ./scripts/download-clang-tools.sh
+
+    - name: Format native code
+      shell: bash
+      run: ./scripts/format-native.sh

docs/developing.md

@@ -95,6 +95,41 @@ nuke MarkdownLintFix
 
 All MarkdownLint tasks require [Node.js](https://nodejs.org/) installed locally.
 
+### Managed code formatting
+
+The .NET code formatting is based on the
+[OpenTelemetry .NET repository](https://github.com/open-telemetry/opentelemetry-dotnet).
+
+Installing formatter:
+
+```sh
+dotnet tool install -g dotnet-format
+```
+
+Formatting (Bash):
+
+```sh
+dotnet-format --folder
+```
+
+### Native code formatting
+
+The C++ code formatting is based on the
+[.NET Runtime repository](https://github.com/dotnet/runtime)
+and [.NET JIT utils repository](https://github.com/dotnet/jitutils).
+
+Installing formatter (Bash):
+
+```sh
+./scripts/download-clang-tools.sh
+```
+
+Formatting (Bash):
+
+```sh
+./scripts/format-native.sh
+```
+
 ## Manual testing
 
 ### Test environment

scripts/download-clang-tools.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+set -eo pipefail
+
+SCRIPT_DIR=$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd)
+
+# guess OS_TYPE if not provided
+if [ -z "$OS_TYPE" ]; then
+  case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
+    cygwin_nt*|mingw*|msys_nt*)
+      OS_TYPE="windows"
+      ;;
+    linux*)
+      if [ "$(ldd /bin/ls | grep -m1 'musl')" ]; then
+        OS_TYPE="linux-musl"
+      else
+        OS_TYPE="linux-glibc"
+      fi
+      ;;
+    darwin*)
+      OS_TYPE="macos"
+      ;;
+  esac
+fi
+
+function DownloadClangTool {
+    if [ "$OS_TYPE" == "windows"  ]; then
+        FILENAME=$1.exe
+    else
+        FILENAME=$1
+    fi
+
+    case "$OS_TYPE" in
+        "linux-glibc")
+            TOOLS_URL=https://clrjit.blob.core.windows.net/clang-tools/ubuntu.18.04-x64/$FILENAME
+            ;;
+        "macos")
+            TOOLS_URL=https://clrjit.blob.core.windows.net/clang-tools/osx.10.15-x64/$FILENAME
+            ;;
+        "windows")
+            TOOLS_URL=https://clrjit.blob.core.windows.net/clang-tools/windows/$FILENAME
+            ;;
+        *)
+            echo "Set the operating system type using the OS_TYPE environment variable. Supported values: linux-glibc, macos, windows." >&2
+            exit 1
+            ;;
+    esac
+
+    cd $SCRIPT_DIR/..
+    mkdir -p bin/artifacts
+    cd bin/artifacts
+
+    curl --retry 5 -o "${FILENAME}" "$TOOLS_URL"
+    chmod +x $FILENAME
+}
+
+DownloadClangTool "clang-format"
+# DownloadClangTool "clang-tidy" # unused

scripts/format-native.sh

@@ -0,0 +1,42 @@
+#!/bin/sh
+
+SCRIPT_DIR=$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd)
+cd $SCRIPT_DIR/..
+
+LC_ALL=C
+
+# guess OS_TYPE if not provided
+if [ -z "$OS_TYPE" ]; then
+  case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
+    cygwin_nt*|mingw*|msys_nt*)
+      OS_TYPE="windows"
+      ;;
+    linux*)
+      if [ "$(ldd /bin/ls | grep -m1 'musl')" ]; then
+        OS_TYPE="linux-musl"
+      else
+        OS_TYPE="linux-glibc"
+      fi
+      ;;
+    darwin*)
+      OS_TYPE="macos"
+      ;;
+  esac
+fi
+
+if [ "$OS_TYPE" == "windows"  ]; then
+    EXT=.exe
+else
+    EXT=
+fi
+
+# files to format
+NATIVE_FILES=$(find . -iname *.cpp -o -iname *.hpp -iname *.h -iname *.inc | grep -v ./packages | grep -v ./src/OpenTelemetry.AutoInstrumentation.Native/lib)
+
+# clang-format
+echo "$NATIVE_FILES" | xargs "./bin/artifacts/clang-format$EXT" -style=file -i
+
+## check if anything changed
+git status
+git diff
+test -z "$(git status --porcelain)"