bindings/python/babeltrace/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 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  26 # SOFTWARE.
  27
  28 import sys
  29 import tempfile
  30 import babeltrace.writer as btw
  31
  32
  33 trace_path = tempfile.mkdtemp()
  34
  35 print("Writing trace at {}".format(trace_path))
  36 writer = btw.Writer(trace_path)
  37
  38 clock = btw.Clock("A_clock")
  39 print("Clock name is \"{}\"".format(clock.name))
  40 clock.description = "Simple clock"
  41 print("Clock description is \"{}\"".format(clock.description))
  42 print("Clock frequency is {}".format(clock.frequency))
  43 print("Clock precision is {}".format(clock.precision))
  44 print("Clock offset_seconds is {}".format(clock.offset_seconds))
  45 print("Clock offset is {}".format(clock.offset))
  46 print("Clock is absolute: {}".format(clock.absolute))
  47 print("Clock time is {}".format(clock.time))
  48 print("Clock UUID is {}".format(clock.uuid))
  49
  50 writer.add_clock(clock)
  51 writer.add_environment_field("Python_version", str(sys.version_info))
  52
  53 stream_class = btw.StreamClass("test_stream")
  54 stream_class.clock = clock
  55
  56 event_class = btw.EventClass("SimpleEvent")
  57
  58 # Create a int32_t equivalent type
  59 int32_type = btw.IntegerFieldDeclaration(32)
  60 int32_type.signed = True
  61
  62 # Create a uint16_t equivalent type
  63 uint16_type = btw.IntegerFieldDeclaration(16)
  64 uint16_type.signed = False
  65
  66 # Add a custom uint16_t field in the stream's packet context
  67 packet_context_type = stream_class.packet_context_type
  68 print("\nFields in default packet context:")
  69 for field in packet_context_type.fields:
  70     print(str(type(field[1])) + " " + field[0])
  71 packet_context_type.add_field(uint16_type, "a_custom_packet_context_field")
  72 stream_class.packet_context_type = packet_context_type
  73
  74 # Create a string type
  75 string_type = btw.StringFieldDeclaration()
  76
  77 # Create a structure type containing both an integer and a string
  78 structure_type = btw.StructureFieldDeclaration()
  79 structure_type.add_field(int32_type, "an_integer")
  80 structure_type.add_field(string_type, "a_string_field")
  81 event_class.add_field(structure_type, "structure_field")
  82
  83 # Create a floating point type
  84 floating_point_type = btw.FloatFieldDeclaration()
  85 floating_point_type.exponent_digits = btw.FloatFieldDeclaration.FLT_EXP_DIG
  86 floating_point_type.mantissa_digits = btw.FloatFieldDeclaration.FLT_MANT_DIG
  87 event_class.add_field(floating_point_type, "float_field")
  88
  89 # Create an enumeration type
  90 int10_type = btw.IntegerFieldDeclaration(10)
  91 enumeration_type = btw.EnumerationFieldDeclaration(int10_type)
  92 enumeration_type.add_mapping("FIRST_ENTRY", 0, 4)
  93 enumeration_type.add_mapping("SECOND_ENTRY", 5, 5)
  94 enumeration_type.add_mapping("THIRD_ENTRY", 6, 10)
  95 event_class.add_field(enumeration_type, "enum_field")
  96
  97 # Create an array type
  98 array_type = btw.ArrayFieldDeclaration(int10_type, 5)
  99 event_class.add_field(array_type, "array_field")
 100
 101 # Create a sequence type
 102 sequence_type = btw.SequenceFieldDeclaration(int32_type, "sequence_len")
 103 event_class.add_field(uint16_type, "sequence_len")
 104 event_class.add_field(sequence_type, "sequence_field")
 105
 106 stream_class.add_event_class(event_class)
 107 stream = writer.create_stream(stream_class)
 108
 109 for i in range(100):
 110     event = btw.Event(event_class)
 111
 112     clock.time = i * 1000
 113     structure_field = event.payload("structure_field")
 114     integer_field = structure_field.field("an_integer")
 115     integer_field.value = i
 116
 117     string_field = structure_field.field("a_string_field")
 118     string_field.value = "Test string."
 119
 120     float_field = event.payload("float_field")
 121     float_field.value = float(i) + (float(i) / 100.0)
 122
 123     array_field = event.payload("array_field")
 124     for j in range(5):
 125         element = array_field.field(j)
 126         element.value = i + j
 127
 128     event.payload("sequence_len").value = i % 10
 129     sequence_field = event.payload("sequence_field")
 130     sequence_field.length = event.payload("sequence_len")
 131     for j in range(event.payload("sequence_len").value):
 132         sequence_field.field(j).value = i + j
 133
 134     enumeration_field = event.payload("enum_field")
 135     integer_field = enumeration_field.container
 136     enumeration_field.value = i % 10
 137
 138     stream.append_event(event)
 139
 140 # Populate custom packet context field before flushing
 141 packet_context = stream.packet_context
 142 field = packet_context.field("a_custom_packet_context_field")
 143 field.value = 42
 144
 145 stream.flush()