#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0-only
#
# Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <bristot@kernel.org>
#
# dot2c: parse an automata in dot file digraph format into a C
#
# This program was written in the development of this paper:
# de Oliveira, D. B. and Cucinotta, T. and de Oliveira, R. S.
# "Efficient Formal Verification for the Linux Kernel." International
# Conference on Software Engineering and Formal Methods. Springer, Cham, 2019.
#
# For further information, see:
# Documentation/trace/rv/deterministic_automata.rst
from dot2.automata import Automata
class Dot2c(Automata):
enum_suffix = ""
enum_states_def = "states"
enum_events_def = "events"
struct_automaton_def = "automaton"
var_automaton_def = "aut"
def __init__(self, file_path):
super().__init__(file_path)
self.line_length = 100
def __buff_to_string(self, buff):
string = ""
for line in buff:
string = string + line + "\n"
# cut off the last \n
return string[:-1]
def __get_enum_states_content(self):
buff = []
buff.append("\t%s%s = 0," % (self.initial_state, self.enum_suffix))
for state in self.states:
if state != self.initial_state:
buff.append("\t%s%s," % (state, self.enum_suffix))
buff.append("\tstate_max%s" % (self.enum_suffix))
return buff
def get_enum_states_string(self):
buff = self.__get_enum_states_content()
return self.__buff_to_string(buff)
def format_states_enum(self):
buff = []
buff.append("enum %s {" % self.enum_states_def)
buff.append(self.get_enum_states_string())
buff.append("};\n")
return buff
def __get_enum_events_content(self):
buff = []
first = True
for event in self.events:
if first:
buff.append("\t%s%s = 0," % (event, self.enum_suffix))
first = False
else:
buff.append("\t%s%s," % (event, self.enum_suffix))
buff.append("\tevent_max%s" % self.enum_suffix)
return buff
def get_enum_events_string(self):
buff = self.__get_enum_events_content()
return self.__buff_to_string(buff)
def format_events_enum(self):
buff = []
buff.append("enum %s {" % self.enum_events_def)
buff.append(self.get_enum_events_string())
buff.append("};\n")
return buff
def get_minimun_type(self):
min_type = "unsigned char"
if self.states.__len__() > 255:
min_type = "unsigned short"
if self.states.__len__() > 65535:
min_type = "unsigned int"
if self.states.__len__() > 1000000:
raise Exception("Too many states: %d" % self.states.__len__())
return min_type
def format_automaton_definition(self):
min_type = self.get_minimun_type()
buff = []
buff.append("struct %s {" % self.struct_automaton_def)
buff.append("\tchar *state_names[state_max%s];" % (self.enum_suffix))
buff.append("\tchar *event_names[event_max%s];" % (self.enum_suffix))
buff.append("\t%s function[state_max%s][event_max%s];" % (min_type, self.enum_suffix, self.enum_suffix))
buff.append("\t%s initial_state;" % min_type)
buff.append("\tbool final_states[state_max%s];" % (self.enum_suffix))
buff.append("};\n")
return buff
def format_aut_init_header(self):
buff = []
buff.append("static const struct %s %s = {" % (self.struct_automaton_def, self.var_automaton_def))
return buff
def __get_string_vector_per_line_content(self, buff):
first = True
string = ""
for entry in buff:
if first:
string = string + "\t\t\"" + entry
first = False;
else:
string = string + "\",\n\t\t\"" + entry
string = string + "\""
return string
def get_aut_init_events_string(self):
return self.__get_string_vector_per_line_content(self.events)
def get_aut_init_states_string(self):
return self.__get_string_vector_per_line_content(self.states)
def format_aut_init_events_string(self):
buff = []
buff.append("\t.event_names = {")
buff.append(self.get_aut_init_events_string())
buff.append("\t},")
return buff
def format_aut_init_states_string(self):
buff = []
buff.append("\t.state_names = {")
buff.append(self.get_aut_init_states_string())
buff.append("\t},")
return buff
def __get_max_strlen_of_states(self):
max_state_name = max(self.states, key = len).__len__()
return max(max_state_name, self.invalid_state_str.__len__())
def __get_state_string_length(self):
maxlen = self.__get_max_strlen_of_states() + self.enum_suffix.__len__()
return "%" + str(maxlen) + "s"
def get_aut_init_function(self):
nr_states = self.states.__len__()
nr_events = self.events.__len__()
buff = []
strformat = self.__get_state_string_length()
for x in range(nr_states):
line = "\t\t{ "
for y in range(nr_events):
next_state = self.function[x][y]
if next_state != self.invalid_state_str:
next_state = self.function[x][y] + self.enum_suffix
if y != nr_events-1:
line = line + strformat % next_state + ", "
else:
line = line + strformat % next_state + " },"
buff.append(line)
return self.__buff_to_string(buff)
def format_aut_init_function(self):
buff = []
buff.append("\t.function = {")
buff.append(self.get_aut_init_function())
buff.append("\t},")
return buff
def get_aut_init_initial_state(self):
return self.initial_state
def format_aut_init_initial_state(self):
buff = []
initial_state = self.get_aut_init_initial_state()
buff.append("\t.initial_state = " + initial_state + self.enum_suffix + ",")
return buff
def get_aut_init_final_states(self):
line = ""
first = True
for state in self.states:
if first == False:
line = line + ', '
else:
first = False
if self.final_states.__contains__(state):
line = line + '1'
else:
line = line + '0'
return line
def format_aut_init_final_states(self):
buff = []
buff.append("\t.final_states = { %s }," % self.get_aut_init_final_states())
return buff
def __get_automaton_initialization_footer_string(self):
footer = "};\n"
return footer
def format_aut_init_footer(self):
buff = []
buff.append(self.__get_automaton_initialization_footer_string())
return buff
def format_invalid_state(self):
buff = []
buff.append("#define %s state_max%s\n" % (self.invalid_state_str, self.enum_suffix))
return buff
def format_model(self):
buff = []
buff += self.format_states_enum()
buff += self.format_invalid_state()
buff += self.format_events_enum()
buff += self.format_automaton_definition()
buff += self.format_aut_init_header()
buff += self.format_aut_init_states_string()
buff += self.format_aut_init_events_string()
buff += self.format_aut_init_function()
buff += self.format_aut_init_initial_state()
buff += self.format_aut_init_final_states()
buff += self.format_aut_init_footer()
return buff
def print_model_classic(self):
buff = self.format_model()
print(self.__buff_to_string(buff))