util/codestyle.sh: Allow using the directive "codestyle:disable" in source files that shouldn't be automatically formatted

src/impl/noise.cpp

@@ -634,3 +634,5 @@ void Noise::transformNoiseMap() {
 }
 
 } // namespace interface
+// codestyle:disable
+// vim: set noet ts=4 sw=4:

src/interface/noise.h

@@ -178,3 +178,5 @@ namespace interface
 				(float)z / np->spread.Z, s + np->seed, np->octaves, np->persist));
 	}
 }
+// codestyle:disable
+// vim: set noet ts=4 sw=4:

util/codestyle.sh

@@ -2,6 +2,19 @@
 set -euv
 script_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
+error() {
+	local parent_lineno="$1"
+	local message="$2"
+	local code="${3:-1}"
+	if [[ -n "$message" ]] ; then
+		echo "Error on or near line ${parent_lineno}: ${message}; exiting with status ${code}"
+		else
+		echo "Error on or near line ${parent_lineno}; exiting with status ${code}"
+	fi
+	exit "${code}"
+}
+trap 'error ${LINENO} "" ""' ERR
+
 header_files="$script_dir"/../src/*/*.h
 cpp_files="$script_dir"/../src/*/*.cpp
 
@@ -20,6 +33,21 @@ lua_files+=" "$(find "$script_dir"/../games -name '*.lua')
 
 cmake_files="$script_dir"/../CMakeLists.txt
 
+# Allow files to disable this script by the special directive
+# 'codestyle:disable'
+function filter_files() {
+	local files=$@
+	for f in $files; do
+		if ! grep -lq 'codestyle:disable' "$f"; then
+			echo "$f"
+		fi
+	done
+}
+header_files=$(filter_files $header_files)
+cpp_files=$(filter_files $cpp_files)
+lua_files=$(filter_files $lua_files)
+cmake_files=$(filter_files $cmake_files)
+
 echo "header_files: $header_files"
 echo "cpp_files: $cpp_files"
 echo "lua_files: $lua_files"