treewide: add .clang-format configuration file

Add the .clang-format configuration file, taken from the Linux kernel
repository. We don't have any official style guidelines in tree at
present, which makes it a bit unclear how to format C code for new
contributors. As well as this, different parts of the codebase seem to
been formatted with different styles on occasion, so using an automatic
formatter should resolve this.

As well as this, replace all the existing indent targets with a single
toplevel `format` target. Managing all the source files to be formatted
is not pretty to maintain, and doesn't really give us much.

Also define a toplevel `check-format` target to verify that all code is
formatted properly. This only becomes useful in the future once we have
reformatted all existing code, but is wired up for now.

For the future:
1. Reformat all existing code. I understand this is a big change, but
   we may as well get all code formatted if we go down this route;
   afterall, it's not like this will cause any breaking changes.

2. Add a CI target to check that all code is formatted as per the new
   clang-format configuration. The `check-format` target can be used
   for this.

Signed-off-by: Rahul Sandhu <[email protected]>
Acked-by: Stephen Smalley <[email protected]>

Author: WavyEbuilder

.clang-format

@@ -0,0 +1,130 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# clang-format configuration file. Intended for clang-format >= 11.
+#
+# For more information, see:
+#
+#   Documentation/dev-tools/clang-format.rst
+#   https://clang.llvm.org/docs/ClangFormat.html
+#   https://clang.llvm.org/docs/ClangFormatStyleOptions.html
+#
+---
+AccessModifierOffset: -4
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands: true
+AlignTrailingComments: false
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: None
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: false
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterClass: false
+  AfterControlStatement: false
+  AfterEnum: false
+  AfterFunction: true
+  AfterNamespace: true
+  AfterObjCDeclaration: false
+  AfterStruct: false
+  AfterUnion: false
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  IndentBraces: false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Custom
+BreakBeforeInheritanceComma: false
+BreakBeforeTernaryOperators: false
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeComma
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: false
+ColumnLimit: 80
+CommentPragmas: '^ IWYU pragma:'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+ConstructorInitializerIndentWidth: 8
+ContinuationIndentWidth: 8
+Cpp11BracedListStyle: false
+DerivePointerAlignment: false
+DisableFormat: false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: false
+
+# Taken from:
+#   git grep -h '^#define [^[:space:]]*for_each[^[:space:]]*(' \
+#   | sed "s,^#define \([^[:space:]]*for_each[^[:space:]]*\)(.*$,  - '\1'," \
+#   | LC_ALL=C sort -u
+ForEachMacros:
+  - 'cil_list_for_each'
+  - 'cil_stack_for_each'
+  - 'cil_stack_for_each_starting_at'
+  - 'ebitmap_for_each_bit'
+  - 'ebitmap_for_each_positive_bit'
+
+IncludeBlocks: Preserve
+IncludeCategories:
+  - Regex: '.*'
+    Priority: 1
+IncludeIsMainRegex: '(Test)?$'
+IndentCaseLabels: false
+IndentGotoLabels: false
+IndentPPDirectives: None
+IndentWidth: 8
+IndentWrappedFunctionNames: false
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+MacroBlockBegin: ''
+MacroBlockEnd: ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 8
+ObjCSpaceAfterProperty: true
+ObjCSpaceBeforeProtocolList: true
+
+# Taken from git's rules
+PenaltyBreakAssignment: 10
+PenaltyBreakBeforeFirstCallParameter: 30
+PenaltyBreakComment: 10
+PenaltyBreakFirstLessLess: 0
+PenaltyBreakString: 10
+PenaltyExcessCharacter: 100
+PenaltyReturnTypeOnItsOwnLine: 60
+
+PointerAlignment: Right
+ReflowComments: false
+SortIncludes: false
+SortUsingDeclarations: false
+SpaceAfterCStyleCast: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatementsExceptForEachMacros
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles: false
+SpacesInContainerLiterals: false
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard: Cpp03
+TabWidth: 8
+UseTab: Always
+...

CONTRIBUTING.md

@@ -53,6 +53,8 @@ When preparing patches, please follow these guidelines:
 -   Separate large patches into logical patches
 -   Patch descriptions must end with your "Signed-off-by" line. This means your
     code meets the Developer's certificate of origin, see below.
+-   C code should be formatted using clang-format, using the .clang-format
+    configuration file at the root of this repository.
 
 When adding new, large features or tools it is best to discuss the
 design on the mailing list prior to submitting the patch.

Makefile

@@ -36,7 +36,7 @@ ifneq ($(DESTDIR),)
 	export LIBSEPOLA
 endif
 
-all install relabel clean test indent:
+all install relabel clean test:
 	@for subdir in $(SUBDIRS); do \
 		(cd $$subdir && $(MAKE) $@) || exit 1; \
 	done
@@ -50,3 +50,12 @@ distclean:
 	@for subdir in $(DISTCLEANSUBDIRS); do \
 		(cd $$subdir && $(MAKE) $@) || exit 1; \
 	done
+
+# We shouldn't have any unformatted files in the repo without an explicit exception.
+FORMAT_SOURCE_FILES := $(shell find $(SUBDIRS) -type f \( -name '*.c' -o -name '*.h' \))
+
+format:
+	clang-format -i $(FORMAT_SOURCE_FILES)
+
+check-format:
+	clang-format --dry-run -Werror $(FORMAT_SOURCE_FILES)

checkpolicy/Makefile

@@ -77,6 +77,3 @@ relabel: install
 clean:
 	-rm -f $(TARGETS) $(CHECKPOLOBJS) $(CHECKMODOBJS) y.tab.c y.tab.h lex.yy.c tests/testpol.conf tests/testpol.bin
 	$(MAKE) -C test clean
-
-indent:
-	../scripts/Lindent $(filter-out $(GENERATED),$(wildcard *.[ch]))

gui/Makefile

@@ -60,8 +60,6 @@ install: all
 clean:
 	(cd po && $(MAKE) $@)
 
-indent:
-
 relabel:
 
 test:

libselinux/Makefile

@@ -50,7 +50,7 @@ COMPILER := clang
 endif
 export COMPILER
 
-all install relabel clean distclean indent:
+all install relabel clean distclean:
 	@for subdir in $(SUBDIRS); do \
 		(cd $$subdir && $(MAKE) $@) || exit 1; \
 	done

libselinux/include/Makefile

@@ -10,9 +10,5 @@ install: all
 
 relabel:
 
-indent:
-	../../scripts/Lindent $(wildcard selinux/*.h)
-
 distclean clean:
 	-rm -f selinux/*~
-

libselinux/man/Makefile

@@ -35,4 +35,4 @@ install: all
 
 relabel:
 
-indent distclean clean:
+format distclean clean:

libselinux/src/Makefile

@@ -223,7 +223,4 @@ clean: clean-pywrap clean-rubywrap
 distclean: clean
 	rm -f $(GENERATED) $(SWIGFILES)
 
-indent:
-	../../scripts/Lindent $(filter-out $(GENERATED),$(wildcard *.[ch]))
-
 .PHONY: all clean clean-pywrap clean-rubywrap pywrap rubywrap swigify install install-pywrap install-rubywrap distclean

libselinux/utils/Makefile

@@ -72,8 +72,4 @@ clean:
 
 distclean: clean
 
-indent:
-	../../scripts/Lindent $(wildcard *.[ch])
-
 relabel:
-