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[babeltrace.git] / src / bindings / python / bt2 / bt2 / trace_class.py

# The MIT License (MIT)
#
# Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
# Copyright (c) 2018 Francis Deslauriers <francis.deslauriers@efficios.com>
# Copyright (c) 2019 Simon Marchi <simon.marchi@efficios.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

__all__ = ['_TraceClass']

import bt2
from bt2 import native_bt, utils, object
import bt2.stream_class
import bt2.field_class
import collections.abc
import functools


class _StreamClassIterator(collections.abc.Iterator):
    def __init__(self, trace_class):
        self._trace_class = trace_class
        self._at = 0

    def __next__(self):
        if self._at == len(self._trace_class):
            raise StopIteration

        borrow_stream_class_fn = native_bt.trace_class_borrow_stream_class_by_index_const
        sc_ptr = borrow_stream_class_fn(self._trace_class._ptr, self._at)
        assert sc_ptr
        id = native_bt.stream_class_get_id(sc_ptr)
        assert id >= 0
        self._at += 1
        return id


def _trace_class_destruction_listener_from_native(user_listener, trace_class_ptr):
    trace_class = bt2.trace_class._TraceClass._create_from_ptr_and_get_ref(trace_class_ptr)
    user_listener(trace_class)


class _TraceClass(object._SharedObject, collections.abc.Mapping):
    _get_ref = staticmethod(native_bt.trace_class_get_ref)
    _put_ref = staticmethod(native_bt.trace_class_put_ref)

    # Instantiate a trace of this class.

    def __call__(self, name=None, uuid=None, env=None):
        trace_ptr = native_bt.trace_create(self._ptr)

        if trace_ptr is None:
            raise bt2.CreationError('cannot create trace class object')

        trace = bt2.trace._Trace._create_from_ptr(trace_ptr)

        if name is not None:
            trace._name = name

        if uuid is not None:
            trace._uuid = uuid

        if env is not None:
            for key, value in env.items():
                trace.env[key] = value

        return trace

    # Number of stream classes in this trace class.

    def __len__(self):
        count = native_bt.trace_class_get_stream_class_count(self._ptr)
        assert count >= 0
        return count

    # Get a stream class by stream id.

    def __getitem__(self, key):
        utils._check_uint64(key)

        sc_ptr = native_bt.trace_class_borrow_stream_class_by_id_const(self._ptr, key)
        if sc_ptr is None:
            raise KeyError(key)

        return bt2.stream_class._StreamClass._create_from_ptr_and_get_ref(sc_ptr)

    def __iter__(self):
        for idx in range(len(self)):
            sc_ptr = native_bt.trace_class_borrow_stream_class_by_index_const(self._ptr, idx)
            assert sc_ptr is not None

            id = native_bt.stream_class_get_id(sc_ptr)
            assert id >= 0

            yield id

    def create_stream_class(self, id=None,
                            name=None,
                            packet_context_field_class=None,
                            event_common_context_field_class=None,
                            default_clock_class=None,
                            assigns_automatic_event_class_id=True,
                            assigns_automatic_stream_id=True,
                            supports_packets=False,
                            packets_have_beginning_default_clock_snapshot=False,
                            packets_have_end_default_clock_snapshot=False,
                            supports_discarded_events=False,
                            discarded_events_have_default_clock_snapshots=False,
                            supports_discarded_packets=False,
                            discarded_packets_have_default_clock_snapshots=False):

        if self.assigns_automatic_stream_class_id:
            if id is not None:
                raise ValueError('id provided, but trace class assigns automatic stream class ids')

            sc_ptr = native_bt.stream_class_create(self._ptr)
        else:
            if id is None:
                raise ValueError('id not provided, but trace class does not assign automatic stream class ids')

            utils._check_uint64(id)
            sc_ptr = native_bt.stream_class_create_with_id(self._ptr, id)

        sc = bt2.stream_class._StreamClass._create_from_ptr(sc_ptr)

        if name is not None:
            sc._name = name

        if event_common_context_field_class is not None:
            sc._event_common_context_field_class = event_common_context_field_class

        if default_clock_class is not None:
            sc._default_clock_class = default_clock_class

        # call after `sc._default_clock_class` because, if
        # `packets_have_beginning_default_clock_snapshot` or
        # `packets_have_end_default_clock_snapshot` is true, then this
        # stream class needs a default clock class already.
        sc._set_supports_packets(supports_packets,
                                 packets_have_beginning_default_clock_snapshot,
                                 packets_have_end_default_clock_snapshot)

        # call after sc._set_supports_packets() because, if
        # `packet_context_field_class` is not `None`, then this stream
        # class needs to support packets already.
        if packet_context_field_class is not None:
            sc._packet_context_field_class = packet_context_field_class

        sc._assigns_automatic_event_class_id = assigns_automatic_event_class_id
        sc._assigns_automatic_stream_id = assigns_automatic_stream_id
        sc._set_supports_discarded_events(supports_discarded_events,
                                          discarded_events_have_default_clock_snapshots)
        sc._set_supports_discarded_packets(supports_discarded_packets,
                                           discarded_packets_have_default_clock_snapshots)
        return sc

    @property
    def assigns_automatic_stream_class_id(self):
        return native_bt.trace_class_assigns_automatic_stream_class_id(self._ptr)

    def _assigns_automatic_stream_class_id(self, auto_id):
        utils._check_bool(auto_id)
        return native_bt.trace_class_set_assigns_automatic_stream_class_id(self._ptr, auto_id)

    _assigns_automatic_stream_class_id = property(fset=_assigns_automatic_stream_class_id)

    # Field class creation methods.

    def _check_create_status(self, ptr, type_name):
        if ptr is None:
            raise bt2.CreationError(
                'cannot create {} field class'.format(type_name))

    def _create_integer_field_class(self, create_func, py_cls, type_name, field_value_range, preferred_display_base):
        field_class_ptr = create_func(self._ptr)
        self._check_create_status(field_class_ptr, type_name)

        field_class = py_cls._create_from_ptr(field_class_ptr)

        if field_value_range is not None:
            field_class._field_value_range = field_value_range

        if preferred_display_base is not None:
            field_class._preferred_display_base = preferred_display_base

        return field_class

    def create_signed_integer_field_class(self, field_value_range=None, preferred_display_base=None):
        return self._create_integer_field_class(native_bt.field_class_signed_integer_create,
                                                bt2.field_class._SignedIntegerFieldClass,
                                                'signed integer', field_value_range, preferred_display_base)

    def create_unsigned_integer_field_class(self, field_value_range=None, preferred_display_base=None):
        return self._create_integer_field_class(native_bt.field_class_unsigned_integer_create,
                                                bt2.field_class._UnsignedIntegerFieldClass,
                                                'unsigned integer', field_value_range, preferred_display_base)

    def create_signed_enumeration_field_class(self, field_value_range=None, preferred_display_base=None):
        return self._create_integer_field_class(native_bt.field_class_signed_enumeration_create,
                                                bt2.field_class._SignedEnumerationFieldClass,
                                                'signed enumeration', field_value_range, preferred_display_base)

    def create_unsigned_enumeration_field_class(self, field_value_range=None, preferred_display_base=None):
        return self._create_integer_field_class(native_bt.field_class_unsigned_enumeration_create,
                                                bt2.field_class._UnsignedEnumerationFieldClass,
                                                'unsigned enumeration', field_value_range, preferred_display_base)

    def create_real_field_class(self, is_single_precision=False):
        field_class_ptr = native_bt.field_class_real_create(self._ptr)
        self._check_create_status(field_class_ptr, 'real')

        field_class = bt2.field_class._RealFieldClass._create_from_ptr(field_class_ptr)

        field_class._is_single_precision = is_single_precision

        return field_class

    def create_structure_field_class(self):
        field_class_ptr = native_bt.field_class_structure_create(self._ptr)
        self._check_create_status(field_class_ptr, 'structure')

        return bt2.field_class._StructureFieldClass._create_from_ptr(field_class_ptr)

    def create_string_field_class(self):
        field_class_ptr = native_bt.field_class_string_create(self._ptr)
        self._check_create_status(field_class_ptr, 'string')

        return bt2.field_class._StringFieldClass._create_from_ptr(field_class_ptr)

    def create_static_array_field_class(self, elem_fc, length):
        utils._check_type(elem_fc, bt2.field_class._FieldClass)
        utils._check_uint64(length)
        ptr = native_bt.field_class_static_array_create(self._ptr, elem_fc._ptr, length)
        self._check_create_status(ptr, 'static array')

        return bt2.field_class._StaticArrayFieldClass._create_from_ptr_and_get_ref(ptr)

    def create_dynamic_array_field_class(self, elem_fc, length_fc=None):
        utils._check_type(elem_fc, bt2.field_class._FieldClass)
        length_fc_ptr = None

        if length_fc is not None:
            utils._check_type(length_fc, bt2.field_class._UnsignedIntegerFieldClass)
            length_fc_ptr = length_fc._ptr

        ptr = native_bt.field_class_dynamic_array_create(self._ptr, elem_fc._ptr, length_fc_ptr)
        self._check_create_status(ptr, 'dynamic array')
        return bt2.field_class._DynamicArrayFieldClass._create_from_ptr(ptr)

    def create_variant_field_class(self, selector_fc=None):
        selector_fc_ptr = None

        if selector_fc is not None:
            utils._check_type(selector_fc, bt2.field_class._IntegerFieldClass)
            selector_fc_ptr = selector_fc._ptr

        ptr = native_bt.field_class_variant_create(self._ptr, selector_fc_ptr)
        self._check_create_status(ptr, 'variant')
        return bt2.field_class._create_field_class_from_ptr_and_get_ref(ptr)

    # Add a listener to be called when the trace class is destroyed.

    def add_destruction_listener(self, listener):

        if not callable(listener):
            raise TypeError("'listener' parameter is not callable")

        fn = native_bt.bt2_trace_class_add_destruction_listener
        listener_from_native = functools.partial(_trace_class_destruction_listener_from_native,
                                                 listener)

        listener_id = fn(self._ptr, listener_from_native)
        if listener_id is None:
            utils._raise_bt2_error('cannot add destruction listener to trace class object')

        return bt2._ListenerHandle(listener_id, self)