style(tox): prepare for fixer scripts

The previous code assumes each tox script is a checker.
We want to add fixer scripts (not voting but editing) soon.

This is the less interesting part of the process,
renaming things and updating comments.

Includes some basic descriptions of how fixers differ from checkers.

Change-Id: I1ca1572a328acd02b41dcf4e70d7cb3746a03b03
Signed-off-by: Vratko Polak <vrpolak@cisco.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/resources/libraries/bash/entry/tox/gpl_license.sh b/resources/libraries/bash/entry/tox/gpl_license.sh
new file mode 100644
index 0000000000..7112075883
--- /dev/null
+++ b/resources/libraries/bash/entry/tox/gpl_license.sh
@@ -0,0 +1,73 @@
+# Copyright (c) 2022 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -exuo pipefail
+
+# This file should be executed from tox, as the assumed working directory
+# is different from where this file is located.
+# This file does not have executable flag nor shebang,
+# to dissuade non-tox callers.
+
+# This script runs a few grep-based commands and fails
+# if it detects any file edited or added since HEAD~
+# containing a copyright notice in first 3 lines,
+# but not GPL-based license.
+# The offending files are stored to gpl_license.log (overwriting).
+
+# "set -eu" handles failures from the following two lines.
+BASH_CHECKS_DIR="$(dirname $(readlink -e "${BASH_SOURCE[0]}"))"
+BASH_FUNCTION_DIR="$(readlink -e "${BASH_CHECKS_DIR}/../../function")"
+source "${BASH_FUNCTION_DIR}/common.sh" || {
+    echo "Source failed." >&2
+    exit 1
+}
+
+IFS=$'\n'
+gpl_files=($(git diff --name-only HEAD~ | grep '^GPL/' || true))
+unset IFS
+logfile="gpl_license.log"
+truncate -s 0 "${logfile}" || die
+# A change can have thousands of files, supress console output in the cycle.
+set +x
+for fil in "${gpl_files[@]}"; do
+    if head -n 3 "${fil}" | fgrep -iq 'Copyright'; then
+        # Copyrighted file, processed below.
+        true
+    else
+        # Uncopyrighted files are allowed.
+        # TODO: Should we have list of extesions that require Copyright?
+        continue
+    fi
+    if fgrep -q 'GNU General Public License v2.0 or later' "${fil}"; then
+        # This can be GPL only or the OR license, we accept both.
+        # TODO: Should we require "Apache-2.0 OR GPL-2.0-or-later"?
+        continue
+    else
+        echo "GPL license not detected: ${fil}" >> "${logfile}"
+    fi
+done
+set -x
+lines="$(< "${logfile}" wc -l)"
+if [ "${lines}" != "0" ]; then
+    # TODO: Decide which text goes to stdout and which to stderr.
+    warn "Wrong licensed files in GPL directory detected: ${lines}"
+    # TODO: Disable when output size does more harm than good.
+    pwd
+    cat "${logfile}" >&2
+    warn
+    warn "GPL license checker: FAIL"
+    exit 1
+fi
+
+warn
+warn "GPL license checker: PASS"