Change the coding style to GNU

.clang-format

@@ -0,0 +1,20 @@
+---
+# Global Options Go Here
+IndentWidth: 2
+ColumnLimit: 100
+---
+Language: Cpp
+BasedOnStyle: GNU
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AlignConsecutiveMacros: true
+ForEachMacros: []
+IndentWidth: 2
+AlignConsecutiveAssignments: Consecutive
+AlignConsecutiveBitFields: Consecutive
+AlignEscapedNewlines: Left
+AlwaysBreakTemplateDeclarations: Yes
+IncludeBlocks: Regroup
+SortIncludes: true
+SortUsingDeclarations: true
+...

.pre-commit-config.yaml

@@ -0,0 +1,31 @@
+# Apply to all files without commiting:
+#   pre-commit run --all-files
+# Update this file:
+#   pre-commit autoupdate
+fail_fast: false
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.3.0
+    hooks:
+    - id: check-added-large-files
+    - id: check-symlinks
+    - id: check-byte-order-marker
+    - id: check-case-conflict
+    - id: check-docstring-first
+    - id: check-executables-have-shebangs
+    - id: forbid-new-submodules
+    - id: end-of-file-fixer
+    - id: trailing-whitespace
+    - id: mixed-line-ending
+
+  - repo: https://github.com/pocc/pre-commit-hooks
+    rev: v1.3.5
+    hooks:
+      - id: clang-format
+      - id: cppcheck
+        args: ['--project=compile_commands.json']
+  - repo: https://github.com/detailyang/pre-commit-shell
+    rev: 1.0.5
+    hooks:
+    - id: shell-lint
+      args: ['-x']

src/feynman.c

@@ -16,6 +16,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include "export.h"
+
 #include <emacs-module.h>
 
 /* Declare mandatory GPL symbol.  */
@@ -23,8 +24,9 @@ FEYNMAN_EXPORT int plugin_is_GPL_compatible = 0;
 
 /* New emacs lisp function. All function exposed to Emacs must have this
  * prototype. */
-static emacs_value feynman_init(emacs_env *env, ptrdiff_t nargs,
-                                emacs_value args[], void *data) {
+static emacs_value
+feynman_init (emacs_env *env, ptrdiff_t nargs, emacs_value args[], void *data)
+{
   (void)nargs;
   (void)args;
   (void)data;
@@ -32,7 +34,9 @@ static emacs_value feynman_init(emacs_env *env, ptrdiff_t nargs,
 }
 
 /* Bind NAME to FUN.  */
-static void bind_function(emacs_env *env, const char *name, emacs_value Sfun) {
+static void
+bind_function (emacs_env *env, const char *name, emacs_value Sfun)
+{
   /* Set the function cell of the symbol named NAME to SFUN using
      the 'fset' function.  */
 
@@ -48,7 +52,9 @@ static void bind_function(emacs_env *env, const char *name, emacs_value Sfun) {
 }
 
 /* Provide FEATURE to Emacs.  */
-static void provide(emacs_env *env, const char *feature) {
+static void
+provide (emacs_env *env, const char *feature)
+{
   /* call 'provide' with FEATURE converted to a symbol */
 
   emacs_value Qfeat    = env->intern (env, feature);
@@ -58,7 +64,9 @@ static void provide(emacs_env *env, const char *feature) {
   env->funcall (env, Qprovide, 1, args);
 }
 
-FEYNMAN_EXPORT int emacs_module_init(struct emacs_runtime *ert) {
+FEYNMAN_EXPORT int
+emacs_module_init (struct emacs_runtime *ert)
+{
   emacs_env *env = ert->get_environment (ert);
   /* create a lambda (returns an emacs_value) */
   emacs_value fun = env->make_function (