bindings/python/examples/ctf_writer.py

   1 #!/usr/bin/env python3
   2 # ctf_writer.py
   3 #
   4 # Babeltrace CTF Writer example script.
   5 #
   6 # Copyright 2013 EfficiOS Inc.
   7 #
   8 # Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
   9 #
  10 # Permission is hereby granted, free of charge, to any person obtaining a copy
  11 # of this software and associated documentation files (the "Software"), to deal
  12 # in the Software without restriction, including without limitation the rights
  13 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14 # copies of the Software, and to permit persons to whom the Software is
  15 # furnished to do so, subject to the following conditions:
  16 #
  17 # The above copyright notice and this permission notice shall be included in
  18 # all copies or substantial portions of the Software.
  19
  20 import sys
  21 import tempfile
  22 from babeltrace import *
  23
  24 trace_path = tempfile.mkdtemp()
  25
  26 print("Writing trace at {}".format(trace_path))
  27 writer = CTFWriter.Writer(trace_path)
  28
  29 clock = CTFWriter.Clock("A_clock")
  30 print("Clock name is \"{}\"".format(clock.name))
  31 clock.description = "Simple clock"
  32 print("Clock description is \"{}\"".format(clock.description))
  33 print("Clock frequency is {}".format(clock.frequency))
  34 print("Clock precision is {}".format(clock.precision))
  35 print("Clock offset_seconds is {}".format(clock.offset_seconds))
  36 print("Clock offset is {}".format(clock.offset))
  37 print("Clock is absolute: {}".format(clock.absolute))
  38 print("Clock time is {}".format(clock.time))
  39
  40 writer.add_clock(clock)
  41 writer.add_environment_field("Python_version", str(sys.version_info))
  42
  43 stream_class = CTFWriter.StreamClass("test_stream")
  44 stream_class.clock = clock
  45
  46 event_class = CTFWriter.EventClass("SimpleEvent")
  47
  48 # Create a int32_t equivalent type
  49 int32_type = CTFWriter.IntegerFieldDeclaration(32)
  50 int32_type.signed = True
  51
  52 # Create a string type
  53 string_type = CTFWriter.StringFieldDeclaration()
  54
  55 # Create a structure type containing both an integer and a string
  56 structure_type = CTFWriter.StructureFieldDeclaration()
  57 structure_type.add_field(int32_type, "an_integer")
  58 structure_type.add_field(string_type, "a_string_field")
  59 event_class.add_field(structure_type, "structure_field")
  60
  61 # Create a floating point type
  62 floating_point_type = CTFWriter.FloatFieldDeclaration()
  63 floating_point_type.exponent_digits = CTFWriter.FloatFieldDeclaration.FLT_EXP_DIG
  64 floating_point_type.mantissa_digits = CTFWriter.FloatFieldDeclaration.FLT_MANT_DIG
  65 event_class.add_field(floating_point_type, "float_field")
  66
  67 # Create an enumeration type
  68 int10_type = CTFWriter.IntegerFieldDeclaration(10)
  69 enumeration_type = CTFWriter.EnumerationFieldDeclaration(int10_type)
  70 enumeration_type.add_mapping("FIRST_ENTRY", 0, 4)
  71 enumeration_type.add_mapping("SECOND_ENTRY", 5, 5)
  72 enumeration_type.add_mapping("THIRD_ENTRY", 6, 10)
  73 event_class.add_field(enumeration_type, "enum_field")
  74
  75 # Create an array type
  76 array_type = CTFWriter.ArrayFieldDeclaration(int10_type, 5)
  77 event_class.add_field(array_type, "array_field")
  78
  79 stream_class.add_event_class(event_class)
  80 stream = writer.create_stream(stream_class)
  81
  82 for i in range(100):
  83         event = CTFWriter.Event(event_class)
  84
  85         clock.time = i * 1000
  86         structure_field = event.payload("structure_field")
  87         integer_field = structure_field.field("an_integer")
  88         integer_field.value = i
  89
  90         string_field = structure_field.field("a_string_field")
  91         string_field.value = "Test string."
  92
  93         float_field = event.payload("float_field")
  94         float_field.value = float(i) + (float(i) / 100.0)
  95
  96         array_field = event.payload("array_field")
  97         for j in range(5):
  98                 element = array_field.field(j)
  99                 element.value = i + j
 100
 101         enumeration_field = event.payload("enum_field")
 102         integer_field = enumeration_field.container
 103         integer_field.value = i % 10
 104
 105         stream.append_event(event)
 106
 107 stream.flush()