Provides a Git pre-commit hook to check Intel copyright header year

Over time, the copyright year or year range becomes out of date if not
kept updated as changes to files with an Intel copyright header are
edited. This client-side pre-commit hook reminds the contributor to
update the year in the copyright header if the contributor has an
intel.com email domain.

Recommended usage is to create a symbolic link to this file:

   cd acrn-hypervisor/.git/hooks; ln -s ../.pre-commit-intel pre-commit

If needed, the check can be ignored by using   git commit --no-verify

Tracked-On: #7668

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>

.pre-commit-intel

@@ -0,0 +1,35 @@
+#!/bin/bash
+#
+# A pre-commit hook script to check that an existing Intel copyright line within
+# the first 15 lines, contains the current year, which would be the last commit
+# date for this file..
+#
+# Create a symbolic link to this file from .git/hooks/pre-commit to enable it:
+#   cd acrn-hypervisor/.git/hooks; ln -s ../.pre-commit-intel pre-commit
+
+# Redirect output to stderr.
+exec 1>&2
+
+# Don't run this pre-commit if the submitter's email is not from intel.com
+EMAIL=$(git config user.email)
+[[ ! "$EMAIL" == *"intel.com" ]] && {  exit 0; }
+
+RED='\033[0;31m'
+NOCOLOR='\033[0m'
+
+found_mismatch=""
+commit_year=$(date +%Y)
+for filename in $(git diff --cached --name-only --diff-filter=ACM)
+do
+   wrong_year=$(head -15 "$filename" | grep -i ".*Copyright.*Intel" | grep -v "$commit_year")
+   [ ! -z "$wrong_year" ] && [ -z "$found_mismatch" ] && { found_mismatch="yes"; \
+       echo -e "\n${RED}ERROR: As an Intel contributor ($EMAIL), " \
+       "keep the Intel copyright year updated: ${NOCOLOR}\n"; }
+
+   [ ! -z "$wrong_year" ] && { echo -e "  ${RED}$filename${NOCOLOR}: $wrong_year "\
+       "${RED}must be updated to contain ${NOCOLOR}$commit_year."; }
+done
+
+# if we had a mismatch hit, exit with an error
+[ ! -z "$found_mismatch" ] && exit -1;
+exit 0;