Add git commit hooks that do some simple checks on commits.

* autogen.sh: Install Git hooks, if using Git.
* build-aux/git-hooks/commit-msg, build-aux/git-hooks/pre-commit:
New files, which are Git hooks that check for portable file names, and
do some simple checks for commit message format.

1 files changed, 46 insertions, 0 deletions

diff --git a/build-aux/git-hooks/pre-commit b/build-aux/git-hooks/pre-commit
new file mode 100755
index 00000000000..c24f9bb48d3
--- /dev/null
+++ b/build-aux/git-hooks/pre-commit
@@ -0,0 +1,46 @@
+#!/bin/sh
+# Check file names in git commits for GNU Emacs.
+
+# Copyright 2014 Free Software Foundation, Inc.
+
+# This file is part of GNU Emacs.
+
+# GNU Emacs is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# GNU Emacs is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+LC_ALL=C
+export LC_ALL
+
+exec >&2
+
+. git-sh-setup
+
+git_diff='git diff --cached --name-only --diff-filter=A'
+ok_chars='\0+[=-=]./0-9A-Z_a-z'
+nbadchars=`$git_diff -z HEAD | tr -d "$ok_chars" | wc -c`
+
+if test "$nbadchars" -ne 0; then
+  echo "File name does not consist of -+./_ or ASCII letters or digits."
+  exit 1
+fi
+
+new_names=`$git_diff HEAD` || exit
+case "
+$new_names" in
+  */-* | *'
+'-*)
+    echo "File name component begins with '-'."
+    exit 1;;
+esac
+
+exec git diff-index --check --cached HEAD --