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 clock.description = "Simple clock"
  31
  32 writer.add_clock(clock)
  33 writer.add_environment_field("Python_version", str(sys.version_info))
  34
  35 stream_class = CTFWriter.StreamClass("test_stream")
  36 stream_class.clock = clock
  37
  38 event_class = CTFWriter.EventClass("SimpleEvent")
  39
  40 # Create a int32_t equivalent type
  41 int32_type = CTFWriter.IntegerFieldDeclaration(32)
  42 int32_type.signed = True
  43
  44 # Create a string type
  45 string_type = CTFWriter.StringFieldDeclaration()
  46
  47 # Create a structure type containing both an integer and a string
  48 structure_type = CTFWriter.StructureFieldDeclaration()
  49 structure_type.add_field(int32_type, "an_integer")
  50 structure_type.add_field(string_type, "a_string_field")
  51 event_class.add_field(structure_type, "structure_field")
  52
  53 # Create a floating point type
  54 floating_point_type = CTFWriter.FloatFieldDeclaration()
  55 floating_point_type.exponent_digits = CTFWriter.FloatFieldDeclaration.FLT_EXP_DIG
  56 floating_point_type.mantissa_digits = CTFWriter.FloatFieldDeclaration.FLT_MANT_DIG
  57 event_class.add_field(floating_point_type, "float_field")
  58
  59 # Create an enumeration type
  60 int10_type = CTFWriter.IntegerFieldDeclaration(10)
  61 enumeration_type = CTFWriter.EnumerationFieldDeclaration(int10_type)
  62 enumeration_type.add_mapping("FIRST_ENTRY", 0, 4)
  63 enumeration_type.add_mapping("SECOND_ENTRY", 5, 5)
  64 enumeration_type.add_mapping("THIRD_ENTRY", 6, 10)
  65 event_class.add_field(enumeration_type, "enum_field")
  66
  67 # Create an array type
  68 array_type = CTFWriter.ArrayFieldDeclaration(int10_type, 5)
  69 event_class.add_field(array_type, "array_field")
  70
  71 stream_class.add_event_class(event_class)
  72 stream = writer.create_stream(stream_class)
  73
  74 for i in range(100):
  75         event = CTFWriter.Event(event_class)
  76
  77         clock.time = i * 1000
  78         structure_field = event.payload("structure_field")
  79         integer_field = structure_field.field("an_integer")
  80         integer_field.value = i
  81
  82         string_field = structure_field.field("a_string_field")
  83         string_field.value = "Test string."
  84
  85         float_field = event.payload("float_field")
  86         float_field.value = float(i) + (float(i) / 100.0)
  87
  88         array_field = event.payload("array_field")
  89         for j in range(5):
  90                 element = array_field.field(j)
  91                 element.value = i + j
  92
  93         enumeration_field = event.payload("enum_field")
  94         integer_field = enumeration_field.container
  95         integer_field.value = i % 10
  96
  97         stream.append_event(event)
  98
  99 stream.flush()