1#!/usr/bin/env python3
2# SPDX-License-Identifier: GPL-2.0-only
3#
4# Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <bristot@kernel.org>
5#
6# dot2k: transform dot files into a monitor for the Linux kernel.
7#
8# For further information, see:
9#   Documentation/trace/rv/da_monitor_synthesis.rst
10
11from dot2.dot2c import Dot2c
12import platform
13import os
14
15class dot2k(Dot2c):
16    monitor_types = { "global" : 1, "per_cpu" : 2, "per_task" : 3 }
17    monitor_templates_dir = "dot2k/rv_templates/"
18    monitor_type = "per_cpu"
19
20    def __init__(self, file_path, MonitorType):
21        super().__init__(file_path)
22
23        self.monitor_type = self.monitor_types.get(MonitorType)
24        if self.monitor_type == None:
25            raise Exception("Unknown monitor type: %s" % MonitorType)
26
27        self.monitor_type = MonitorType
28        self.__fill_rv_templates_dir()
29        self.main_c = self.__open_file(self.monitor_templates_dir + "main_" + MonitorType + ".c")
30        self.enum_suffix = "_%s" % self.name
31
32    def __fill_rv_templates_dir(self):
33
34        if os.path.exists(self.monitor_templates_dir) == True:
35            return
36
37        if platform.system() != "Linux":
38            raise Exception("I can only run on Linux.")
39
40        kernel_path = "/lib/modules/%s/build/tools/verification/dot2/dot2k_templates/" % (platform.release())
41
42        if os.path.exists(kernel_path) == True:
43            self.monitor_templates_dir = kernel_path
44            return
45
46        if os.path.exists("/usr/share/dot2/dot2k_templates/") == True:
47            self.monitor_templates_dir = "/usr/share/dot2/dot2k_templates/"
48            return
49
50        raise Exception("Could not find the template directory, do you have the kernel source installed?")
51
52
53    def __open_file(self, path):
54        try:
55            fd = open(path)
56        except OSError:
57            raise Exception("Cannot open the file: %s" % path)
58
59        content = fd.read()
60
61        return content
62
63    def __buff_to_string(self, buff):
64        string = ""
65
66        for line in buff:
67            string = string + line + "\n"
68
69        # cut off the last \n
70        return string[:-1]
71
72    def fill_tracepoint_handlers_skel(self):
73        buff = []
74        for event in self.events:
75            buff.append("static void handle_%s(void *data, /* XXX: fill header */)" % event)
76            buff.append("{")
77            if self.monitor_type == "per_task":
78                buff.append("\tstruct task_struct *p = /* XXX: how do I get p? */;");
79                buff.append("\tda_handle_event_%s(p, %s%s);" % (self.name, event, self.enum_suffix));
80            else:
81                buff.append("\tda_handle_event_%s(%s%s);" % (self.name, event, self.enum_suffix));
82            buff.append("}")
83            buff.append("")
84        return self.__buff_to_string(buff)
85
86    def fill_tracepoint_attach_probe(self):
87        buff = []
88        for event in self.events:
89            buff.append("\trv_attach_trace_probe(\"%s\", /* XXX: tracepoint */, handle_%s);" % (self.name, event))
90        return self.__buff_to_string(buff)
91
92    def fill_tracepoint_detach_helper(self):
93        buff = []
94        for event in self.events:
95            buff.append("\trv_detach_trace_probe(\"%s\", /* XXX: tracepoint */, handle_%s);" % (self.name, event))
96        return self.__buff_to_string(buff)
97
98    def fill_main_c(self):
99        main_c = self.main_c
100        min_type = self.get_minimun_type()
101        nr_events = self.events.__len__()
102        tracepoint_handlers = self.fill_tracepoint_handlers_skel()
103        tracepoint_attach = self.fill_tracepoint_attach_probe()
104        tracepoint_detach = self.fill_tracepoint_detach_helper()
105
106        main_c = main_c.replace("MIN_TYPE", min_type)
107        main_c = main_c.replace("MODEL_NAME", self.name)
108        main_c = main_c.replace("NR_EVENTS", str(nr_events))
109        main_c = main_c.replace("TRACEPOINT_HANDLERS_SKEL", tracepoint_handlers)
110        main_c = main_c.replace("TRACEPOINT_ATTACH", tracepoint_attach)
111        main_c = main_c.replace("TRACEPOINT_DETACH", tracepoint_detach)
112
113        return main_c
114
115    def fill_model_h_header(self):
116        buff = []
117        buff.append("/*")
118        buff.append(" * Automatically generated C representation of %s automaton" % (self.name))
119        buff.append(" * For further information about this format, see kernel documentation:")
120        buff.append(" *   Documentation/trace/rv/deterministic_automata.rst")
121        buff.append(" */")
122        buff.append("")
123
124        return buff
125
126    def fill_model_h(self):
127        #
128        # Adjust the definition names
129        #
130        self.enum_states_def = "states_%s" % self.name
131        self.enum_events_def = "events_%s" % self.name
132        self.struct_automaton_def = "automaton_%s" % self.name
133        self.var_automaton_def = "automaton_%s" % self.name
134
135        buff = self.fill_model_h_header()
136        buff += self.format_model()
137
138        return self.__buff_to_string(buff)
139
140    def __create_directory(self):
141        try:
142            os.mkdir(self.name)
143        except FileExistsError:
144            return
145        except:
146            print("Fail creating the output dir: %s" % self.name)
147
148    def __create_file(self, file_name, content):
149        path = "%s/%s" % (self.name, file_name)
150        try:
151            file = open(path, 'w')
152        except FileExistsError:
153            return
154        except:
155            print("Fail creating file: %s" % path)
156
157        file.write(content)
158
159        file.close()
160
161    def __get_main_name(self):
162        path = "%s/%s" % (self.name, "main.c")
163        if os.path.exists(path) == False:
164           return "main.c"
165        return "__main.c"
166
167    def print_files(self):
168        main_c = self.fill_main_c()
169        model_h = self.fill_model_h()
170
171        self.__create_directory()
172
173        path = "%s.c" % self.name
174        self.__create_file(path, main_c)
175
176        path = "%s.h" % self.name
177        self.__create_file(path, model_h)
178