Source code for classes.multi_serial

try:
	from serial import Serial
except:
	pass
from struct import unpack
import time
import threading

class MultiSerial(Serial):
	'''This class should be used for all serial connections. It inherits the pyserial class and
	adds the in_buffer(), print_buffer() and clear_buffer() functions. For easy thread save
	communication with the serially connected devices'''
	buffer  = ''

	def __init__(self, *args, **kwrags):
		# call default (base) constructor
		Serial.__init__(self, *args, **kwrags)
		self.lock = None
		self.lock_given = False

	def in_buffer(self, answer,tail_bytes=0):
		'''
		This function updates the serial buffer and searches for patterns(answer) inside the buffer.
		If found the answer and the following tail_bytes are deleted from the buffer. The function
		should be used to check whether the slave reported a certain answer.

		:param answer: the pattern to search for in the buffer
		:type answer: string

		:param tail_bytes: number of bytes following the pattern to be deleted if pattern was found
		:type tail_bytes: integer
		'''
		response = Serial.read(self, 1)
		while map(hex,unpack('B'*len(response),response)) != []:
				self.buffer = self.buffer + response
				response = Serial.read(self,1)

		if answer in self.buffer:
			if tail_bytes != 0:
				Serial.read(self,tail_bytes)

				index = self.buffer.find(answer)
				self.buffer = self.buffer[:index]+self.buffer[index+len(answer)+tail_bytes:]

			else:
				self.buffer = self.buffer.replace(answer,'')

			return True
		else:
			return False

	def print_buffer(self):
		'''
		Prints the current buffer. The buffer is printed is interpreted as hex numbers and send to print
		'''

		print 'Ascii-fied Hex Representation of Buffer:'
		print map(hex,unpack('B'*len(self.buffer),self.buffer))

	def clear_buffer(self):
		'''
		Empties the current buffer and calls Serial.flushInput() Serial.flushOutput().
		'''
		self.buffer = ''
		Serial.flushInput()
		Serial.flushOutput()


'''
Copyright (C) 2017  Robert Polster
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''