Bug #202068 - In order to filter unwanted variable assignments out

of the bash environment, use a filter-bash-environment.py script
that behaves similar to egrep -v except that it leaves bash here-
documents intact.

svn path=/main/trunk/; revision=8892

1 files changed, 52 insertions, 0 deletions

diff --git a/bin/filter-bash-environment.py b/bin/filter-bash-environment.py
new file mode 100755
index 000000000..83b250b69
--- /dev/null
+++ b/bin/filter-bash-environment.py
@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+# Copyright 1999-2007 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Id$
+
+import os, re, sys
+
+egrep_compat_map = {
+	"[:alnum:]" : r'\w',
+	"[:space:]" : r'\s',
+}
+
+here_doc_re = re.compile(r'.*\s<<[-]?(\w+)$')
+
+def compile_egrep_pattern(s):
+	for k, v in egrep_compat_map.iteritems():
+		s = s.replace(k, v)
+	return re.compile(s)
+
+def filter_bash_environment(pattern, file_in, file_out):
+	here_doc_delim = None
+	for line in file_in:
+		if here_doc_delim is not None:
+			if here_doc_delim.match(line):
+				here_doc_delim = None
+			file_out.write(line)
+			continue
+		here_doc = here_doc_re.match(line)
+		if here_doc is not None:
+			here_doc_delim = re.compile("^%s$" % here_doc.group(1))
+			file_out.write(line)
+			continue
+		if pattern.match(line) is None:
+			file_out.write(line)
+
+if __name__ == "__main__":
+	description = "Filter out any lines that match a given PATTERN " + \
+		"while leaving bash here-documents intact. The PATTERN should " + \
+		"use python regular expression syntax but [:space:] and " + \
+		"[:alnum:] character classes will be automatically translated " + \
+		"for compatibility with egrep syntax."
+	usage = "usage: %s PATTERN" % os.path.basename(sys.argv[0])
+	from optparse import OptionParser
+	parser = OptionParser(description=description, usage=usage)
+	options, args = parser.parse_args(sys.argv[1:])
+	if len(args) != 1:
+		parser.error("Missing required PATTERN argument.")
+	file_in = sys.stdin
+	file_out = sys.stdout
+	filter_bash_environment(
+		compile_egrep_pattern(args[0]), file_in, file_out)
+	file_out.flush()