Index: samesite.py
==================================================================
--- samesite.py
+++ samesite.py
@@ -10,10 +10,12 @@
 		},
 		'_other': {
 			'verbose': 'no',
 			'noetag': 'no',
 			'noparts': 'no',
+			'strip': '',
+			'sub': '',
 	},}
 
 	# function to read in config file
 	def __init__(self):
 		import configparser, optparse
@@ -72,12 +74,20 @@
 
 config = Config()
 
 #assert options.port or os.access(options.log, os.R_OK), 'Log file unreadable'
 
-const_desc_fields = set(['Content-Length', 'Pragma', 'Last-Modified'])
-const_ignore_fields = set(['Accept-Ranges', 'Age', 'Cache-Control', 'Connection', 'Content-Type', 'Date', 'Expires', 'Server', 'Via', 'X-Cache', 'X-Cache-Lookup', 'X-Powered-By'])
+const_desc_fields = set(['Content-Length', 'Last-Modified', 'Pragma'])
+const_ignore_fields = set([
+	'Accept-Ranges', 'Age',
+	'Cache-Control', 'Connection', 'Content-Type',
+	'Date',
+	'Expires',
+	'Server',
+	'Via',
+	'X-Cache', 'X-Cache-Lookup', 'X-Powered-By'
+])
 
 block_size = 4096
 
 '''
 # later, kqueue would be good but later
@@ -193,19 +203,24 @@
 			file_stat = None
 			# requested_ranges holds data about any range requested
 			requested_ranges = None
 			# records holds data from index locally, should be written back upon successfull completion
 			record = None
-			info = 'Checking file: ' + self.path
 
 			myPath = re.compile('^(.*?)(\?.*)$').match(self.path)
 			if myPath:
 				my_path = myPath.group(1)
 			else:
 				my_path = self.path
 
 			config.section(self.headers['Host'])
+
+			if config['sub'] != None and config['strip'] != None and len(config['strip']) > 0:
+				string = re.compile(config['strip']).sub(config['sub'], my_path)
+				my_path = string
+
+			info = 'Checking file: ' + my_path
 
 			if not os.access(config['dir'], os.X_OK):
 				os.mkdir(config['dir'])
 			# this is file index - everything is stored in this file
 			# _parts - list of stored parts of file
@@ -218,18 +233,20 @@
 			if not config['noetag']:
 				desc_fields.add('ETag')
 			else:
 				ignore_fields.add('ETag')
 
-			proxy_ignored = ('Accept', 'Accept-Encoding',
-				'Cache-Control', 'Connection',
+			proxy_ignored = set([
+				'Accept', 'Accept-Charset', 'Accept-Encoding', 'Accept-Language',
+				'Cache-Control', 'Connection', 'Content-Length', 'Cookie',
 				'Host',
 				'If-Modified-Since', 'If-Unmodified-Since',
+				'Referer',
 				'User-Agent',
 				'Via',
-				'X-Forwarded-For',
-			)
+				'X-Forwarded-For', 'X-REMOVED',
+			])
 
 			print('===============[ {} request ]==='.format(self.command))
 
 			for header in self.headers:
 				if header in proxy_ignored:
@@ -271,12 +288,10 @@
 					info += '\nFile not found or inaccessible.'
 					index[my_path]['_parts'] = None
 					reload = True
 				record = index[my_path]
 
-			print(record)
-
 			if not '_parts' in record:
 				record['_parts'] = None
 
 			if record['_parts'] == None:
 				recheck = True
@@ -300,11 +315,16 @@
 
 			print(info)
 			if reload or recheck:
 
 				try:
-					request = 'http://' + config['root'] + my_path
+					request = 'http://' + config['root'] + self.path
+					my_headers = {}
+					for header in ('Cache-Control', 'Cookie', 'Referer', 'User-Agent'):
+						if header in self.headers:
+							my_headers[header] = self.headers[header]
+
 					needed = None
 					# XXX and if we specify full file we don't go partial?
 					if requested_ranges != None:
 						if '_parts' in record and record['_parts'] != None:
 							if config['noparts']:
@@ -320,11 +340,13 @@
 							while True:
 								range = needed.pop()
 								if range[0] == None:
 									break
 								ranges += '{}-{}'.format(range[0], range[1] - 1),
-							request = urllib.request.Request(request, headers = {'Range': 'bytes=' + ','.join(ranges)})
+							my_headers['Range'] = 'bytes=' + ','.join(ranges)
+
+					request = urllib.request.Request(request, headers = my_headers)
 
 					with urllib.request.urlopen(request) as source:
 						new_record = {}
 						new_record['_parts'] = record['_parts']
 						headers = source.info()
@@ -435,15 +457,20 @@
 				except urllib.error.HTTPError as error:
 					# in case of error we don't need to do anything actually,
 					# if file download stalls or fails the file would not be moved to it's location
 					print(error)
 
-			if '_parts' in index[my_path] and index[my_path]['_parts'] == spacemap.SpaceMap():
+			if not os.access(file_name, os.R_OK) and os.access(temp_name, os.R_OK) and '_parts' in index[my_path] and index[my_path]['_parts'] == spacemap.SpaceMap():
 				# just moving
 				# drop old dirs XXX
 				print('Moving temporary file to new destination.')
 				os.renames(temp_name, file_name)
+
+			if not my_path in index:
+				self.send_response(502)
+				self.end_headers()
+				return
 
 			if self.command == 'HEAD':
 				self.send_response(200)
 				if 'Content-Length' in index[my_path]:
 					self.send_header('Content-Length', index[my_path]['Content-Length'])
@@ -470,11 +497,12 @@
 						self.send_header('Content-Range', 'bytes {}/{}'.format(','.join(ranges), index[my_path]['Content-Length']))
 					else:
 						self.send_response(200)
 						self.send_header('Content-Length', str(file_stat.st_size))
 						requested_ranges = spacemap.SpaceMap({0: file_stat.st_size})
-					self.send_header('Last-Modified', index[my_path]['Last-Modified'])
+					if 'Last-Modified' in index[my_path]:
+						self.send_header('Last-Modified', index[my_path]['Last-Modified'])
 					self.send_header('Content-Type', 'application/octet-stream')
 					self.end_headers()
 					if self.command in ('GET'):
 						if len(requested_ranges) > 0:
 							requested_ranges.rewind()