--- /dev/null
+#!/bin/bash
+# Copyright (c) 2015, David Martin
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+# list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# git pre-commit hook that runs an clang-format stylecheck.
+# Features:
+# - abort commit when commit does not comply with the style guidelines
+# - create a patch of the proposed style changes
+
+# modifications for clang-format by rene.milk@wwu.de
+# This file is part of a set of unofficial pre-commit hooks available
+# at github.
+# Link: https://github.com/githubbrowser/Pre-commit-hooks
+# Contact: David Martin, david.martin.mailbox@googlemail.com
+
+
+##################################################################
+# SETTINGS
+# set path to clang-format binary
+CLANG_FORMAT=$(which clang-format)
+
+# remove any older patches from previous commits. Set to true or false.
+DELETE_OLD_PATCHES=false
+
+# only parse files with the extensions in FILE_EXTS. Set to true or false.
+# if false every changed file in the commit will be parsed with clang-format.
+# if true only files matching one of the extensions are parsed with clang-format.
+PARSE_EXTS=true
+
+# file types to parse. Only effective when PARSE_EXTS is true.
+# FILE_EXTS=".c .h .cpp .hpp"
+FILE_EXTS=".c .h .cpp .hpp .cc .hh .cxx"
+
+##################################################################
+# There should be no need to change anything below this line.
+
+# Reference: http://stackoverflow.com/questions/1055671/how-can-i-get-the-behavior-of-gnus-readlink-f-on-a-mac
+canonicalize_filename () {
+ local target_file=$1
+ local physical_directory=""
+ local result=""
+
+ # Need to restore the working directory after work.
+ pushd `pwd` > /dev/null
+
+ cd "$(dirname "$target_file")"
+ target_file=`basename $target_file`
+
+ # Iterate down a (possible) chain of symlinks
+ while [ -L "$target_file" ]
+ do
+ target_file=$(readlink "$target_file")
+ cd "$(dirname "$target_file")"
+ target_file=$(basename "$target_file")
+ done
+
+ # Compute the canonicalized name by finding the physical path
+ # for the directory we're in and appending the target file.
+ physical_directory=`pwd -P`
+ result="$physical_directory"/"$target_file"
+
+ # restore the working directory after work.
+ popd > /dev/null
+
+ echo "$result"
+}
+
+# exit on error
+set -e
+
+# check whether the given file matches any of the set extensions
+matches_extension() {
+ local filename=$(basename "$1")
+ local extension=".${filename##*.}"
+ local ext
+
+ for ext in $FILE_EXTS; do [[ "$ext" == "$extension" ]] && return 0; done
+
+ return 1
+}
+
+# necessary check for initial commit
+if git rev-parse --verify HEAD >/dev/null 2>&1 ; then
+ against=HEAD
+else
+ # Initial commit: diff against an empty tree object
+ against=foobaridonotexist
+fi
+
+if [ ! -x "$CLANG_FORMAT" ] ; then
+ printf "Error: clang-format executable not found.\n"
+ printf "Set the correct path in $(canonicalize_filename "$0").\n"
+ exit 1
+fi
+
+# create a random filename to store our generated patch
+prefix="pre-commit-clang-format"
+suffix="$(date +%s)"
+patch="/tmp/$prefix-$suffix.patch"
+
+# clean up any older clang-format patches
+$DELETE_OLD_PATCHES && rm -f /tmp/$prefix*.patch
+
+# create one patch containing all changes to the files
+git diff-index --cached --diff-filter=ACMR --name-only $against -- | while read file;
+do
+ # ignore file if we do check for file extensions and the file
+ # does not match any of the extensions specified in $FILE_EXTS
+ if $PARSE_EXTS && ! matches_extension "$file"; then
+ continue;
+ fi
+
+ # clang-format our sourcefile, create a patch with diff and append it to our $patch
+ # The sed call is necessary to transform the patch from
+ # --- $file timestamp
+ # +++ - timestamp
+ # to both lines working on the same file and having a a/ and b/ prefix.
+ # Else it can not be applied with 'git apply'.
+ git clang-format --diff -q >> "$patch"
+ #"$CLANG_FORMAT" -style=file "$file" | \
+ #diff -u "$file" - | \
+ #sed -e "1s|--- |--- a/|" -e "2s|+++ -|+++ b/$file|" >> "$patch"
+done
+
+# if no patch has been generated all is ok, clean up the file stub and exit
+if [ ! -s "$patch" ] ; then
+ printf "Files in this commit comply with the clang-format rules.\n"
+ rm -f "$patch"
+ exit 0
+fi
+
+# a patch has been created, notify the user and exit
+printf "\nThe following differences were found between the code to commit "
+printf "and the clang-format rules:\n\n"
+cat "$patch"
+
+printf "\nYou can apply these changes with:\n git apply $patch\n"
+printf "(may need to be called from the root directory of your repository)\n"
+printf "\nNote: git apply only modifies your working directory, but not your index, i.e., not what you want to commit.\n"
+printf "You need to run 'git add' again after you applied this patch OR just run git apply a second time:"
+printf "\n git apply --cached $patch\n\n"
+printf "Aborting commit. Apply changes and commit again or skip checking with"
+printf " --no-verify (not recommended).\n"
+
+exit 1
