python_shebangs

#!/bin/sh
# This is not run by default because - regardless of what
# certain other distributions may think - an unversioned
# python shebang being defined as "give me the latest
# and greatest python available" is very much allowed.
#
# It is provided because it makes sense to have versioned
# shebangs on projects not compatible with a new version.

if [ -z "$RPM_BUILD_ROOT" ]; then
	printf '%s\n' "No build root defined" >&2
	exit 1
fi

if [ ! -d "$RPM_BUILD_ROOT" ]; then
	printf '%s\n' "Invalid build root" >&2
	exit 1
fi

set -efu
# We fork a subshell, so working with a variable is not possible,
# otherwise we will have to switch to bashisms and require /dev/fd/*
tmpfile="$(mktemp)"
trap 'rm -f "$tmpfile"' EXIT
printf '%s\n' "0" > "$tmpfile"

for dir in /bin /usr/bin /sbin /usr/sbin /usr/libexec; do
	if [ ! -d "${RPM_BUILD_ROOT}/${dir}" ]; then
		continue
	fi
	find "${RPM_BUILD_ROOT}/${dir}" -type f -print | \
	while read -r file; do
		# Prohibit shebangs like:
		# #!/usr/bin/python
		# #! /usr/bin/python
		# #!/usr/bin/env python
		# #! /usr/bin/env python
		# Note that a space may be in the end of the shebang line
		if head -n 1 "$file" | grep -qE '^#!([[:blank:]])*.*(/python|[[:blank:]]python)([[:blank:]])*$' ; then
			printf '%s\n' "Unversioned Python shebangs are not allowed. Specify python3 or python2 explicitly in $file"
			# Do not fail on the 1st error, print all errors at one time
			printf '%s\n' "1" > "$tmpfile"
		fi
	done
done

if [ "$(head -n 1 "$tmpfile")" != 0 ]; then
	exit 1
fi