path: root/pysnmp/smi/mibs/SNMPv2-TC.py

#
# This file is part of pysnmp software.
#
# Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
# License: http://snmplabs.com/pysnmp/license.html
#
# ASN.1 source http://mibs.snmplabs.com/asn1/SNMPv2-TC
# Produced by pysmi-0.4.0 at Sun Feb 17 00:21:05 2019
#
# Parts of otherwise autogenerated MIB has been updated manually.
#
import inspect
import string

from pyasn1.compat import octets
from pyasn1.type import univ
from pyasn1.type.base import Asn1Item

from pysnmp import debug
from pysnmp.smi.error import *

(Integer,
 OctetString,
 ObjectIdentifier) = mibBuilder.importSymbols(
    "ASN1",
    "Integer",
    "OctetString",
    "ObjectIdentifier")

(NamedValues,) = mibBuilder.importSymbols(
    "ASN1-ENUMERATION",
    "NamedValues")

(ConstraintsIntersection,
 SingleValueConstraint,
 ValueRangeConstraint,
 ValueSizeConstraint,
 ConstraintsUnion) = mibBuilder.importSymbols(
    "ASN1-REFINEMENT",
    "ConstraintsIntersection",
    "SingleValueConstraint",
    "ValueRangeConstraint",
    "ValueSizeConstraint",
    "ConstraintsUnion")

(ModuleCompliance,
 NotificationGroup) = mibBuilder.importSymbols(
    "SNMPv2-CONF",
    "ModuleCompliance",
    "NotificationGroup")

(MibScalar,
 MibTable,
 MibTableRow,
 MibTableColumn,
 MibIdentifier,
 Unsigned32,
 Gauge32,
 NotificationType,
 Counter64,
 ObjectIdentity,
 Bits,
 Counter32,
 ModuleIdentity,
 IpAddress,
 TimeTicks,
 Integer32,
 iso) = mibBuilder.importSymbols(
    "SNMPv2-SMI",
    "MibScalar",
    "MibTable",
    "MibTableRow",
    "MibTableColumn",
    "MibIdentifier",
    "Unsigned32",
    "Gauge32",
    "NotificationType",
    "Counter64",
    "ObjectIdentity",
    "Bits",
    "Counter32",
    "ModuleIdentity",
    "IpAddress",
    "TimeTicks",
    "Integer32",
    "iso")


class TextualConvention(object):
    displayHint = ''
    status = 'current'
    description = ''
    reference = ''
    bits = ()
    __integer = Integer()
    __unsigned32 = Unsigned32()
    __timeticks = TimeTicks()
    __octetString = OctetString()

    def getDisplayHint(self):
        return self.displayHint

    def getStatus(self):
        return self.status

    def getDescription(self):
        return self.description

    def getReference(self):
        return self.reference

    def getValue(self):
        return self.clone()

    def setValue(self, value):
        if value is None:
            value = univ.noValue
        return self.clone(value)

    def prettyOut(self, value):  # override asn1 type method
        """Implements DISPLAY-HINT evaluation"""
        if self.displayHint and (self.__integer.isSuperTypeOf(self, matchConstraints=False) and not self.getNamedValues() or
                                 self.__unsigned32.isSuperTypeOf(self, matchConstraints=False) or
                                 self.__timeticks.isSuperTypeOf(self, matchConstraints=False)):
            _ = lambda t, f=0: (t, f)
            displayHintType, decimalPrecision = _(*self.displayHint.split('-'))
            if displayHintType == 'x':
                return '0x%x' % value
            elif displayHintType == 'd':
                try:
                    return '%.*f' % (int(decimalPrecision), float(value) / pow(10, int(decimalPrecision)))
                except Exception as exc:
                    raise SmiError(
                        'float evaluation error: %s' % exc
                    )
            elif displayHintType == 'o':
                return '0%o' % value
            elif displayHintType == 'b':
                runningValue = value
                outputValue = ['B']
                while runningValue:
                    outputValue.insert(0, '%d' % (runningValue & 0x01))
                    runningValue >>= 1
                return ''.join(outputValue)
            else:
                raise SmiError(
                    'Unsupported numeric type spec "%s" at %s' % (displayHintType, self.__class__.__name__)
                )
        elif self.displayHint and self.__octetString.isSuperTypeOf(self, matchConstraints=False):
            outputValue = ''
            runningValue = OctetString(value).asOctets()
            displayHint = self.displayHint
            while runningValue and displayHint:
                # 1
                if displayHint[0] == '*':
                    repeatIndicator = repeatCount = octets.oct2int(runningValue[0])
                    displayHint = displayHint[1:]
                    runningValue = runningValue[1:]
                else:
                    repeatCount = 1
                    repeatIndicator = None

                # 2
                octetLength = ''
                while displayHint and displayHint[0] in string.digits:
                    octetLength += displayHint[0]
                    displayHint = displayHint[1:]

                # length is manatory, but people ignore that
                if not octetLength:
                    octetLength = len(runningValue)

                try:
                    octetLength = int(octetLength)
                except Exception:
                    raise SmiError(
                        'Bad octet length: %s' % octetLength
                    )

                if not displayHint:
                    raise SmiError(
                        'Short octet length: %s' % self.displayHint
                    )

                # 3
                displayFormat = displayHint[0]
                displayHint = displayHint[1:]

                # 4
                if displayHint and displayHint[0] not in string.digits and displayHint[0] != '*':
                    displaySep = displayHint[0]
                    displayHint = displayHint[1:]
                else:
                    displaySep = ''

                # 5
                if displayHint and displaySep and repeatIndicator is not None:
                    repeatTerminator = displayHint[0]
                    displaySep = ''
                    displayHint = displayHint[1:]
                else:
                    repeatTerminator = None

                while repeatCount:
                    repeatCount -= 1
                    if displayFormat == 'a':
                        outputValue += runningValue[:octetLength].decode('ascii', 'ignore')
                    elif displayFormat == 't':
                        outputValue += runningValue[:octetLength].decode('utf-8', 'ignore')
                    elif displayFormat in ('x', 'd', 'o'):
                        number = 0
                        numberString = runningValue[:octetLength]
                        while numberString:
                            number <<= 8
                            try:
                                number |= octets.oct2int(numberString[0])
                                numberString = numberString[1:]
                            except Exception as exc:
                                raise SmiError(
                                    'Display format eval failure: %s: %s'
                                    % (numberString, exc)
                                )
                        if displayFormat == 'x':
                            outputValue += '%02x' % number
                        elif displayFormat == 'o':
                            outputValue += '%03o' % number
                        else:
                            outputValue += '%d' % number
                    else:
                        raise SmiError(
                            'Unsupported display format char: %s' %
                            displayFormat
                        )
                    if runningValue and repeatTerminator:
                        outputValue += repeatTerminator
                    runningValue = runningValue[octetLength:]
                if runningValue and displaySep:
                    outputValue += displaySep
                if not displayHint:
                    displayHint = self.displayHint

            return outputValue

        for base in inspect.getmro(self.__class__):
            if not issubclass(base, TextualConvention) and issubclass(base, Asn1Item):
                return base.prettyOut(self, value)

        raise SmiError('TEXTUAL-CONVENTION has no underlying SNMP base type')

    def prettyIn(self, value):  # override asn1 type method
        """Implements DISPLAY-HINT parsing into base SNMP value

        Proper parsing seems impossible due to ambiguities.
        Here we are trying to do our best, but be prepared
        for failures on complicated DISPLAY-HINTs.

        Keep in mind that this parser only works with "text"
        input meaning `unicode` (Py2) or `str` (Py3).
        """
        for base in inspect.getmro(self.__class__):
            if not issubclass(base, TextualConvention) and issubclass(base, Asn1Item):
                break
        else:
            raise SmiError('TEXTUAL-CONVENTION has no underlying SNMP base type')

        if self.displayHint and (self.__integer.isSuperTypeOf(self, matchConstraints=False) and
                                 self.getNamedValues() or
                                 self.__unsigned32.isSuperTypeOf(self, matchConstraints=False) or
                                 self.__timeticks.isSuperTypeOf(self, matchConstraints=False)):
            value = str(value)

            _ = lambda t, f=0: (t, f)
            displayHintType, decimalPrecision = _(*self.displayHint.split('-'))
            if displayHintType == 'x' and (value.startswith('0x') or value.startswith('-0x')):
                try:
                    if value.startswith('-'):
                        return base.prettyIn(self, -int(value[3:], 16))
                    else:
                        return base.prettyIn(self, int(value[2:], 16))
                except Exception as exc:
                    raise SmiError(
                        'integer evaluation error: %s' % exc
                    )
            elif displayHintType == 'd':
                try:
                    return base.prettyIn(self, int(float(value) * 10**int(decimalPrecision)))
                except Exception as exc:
                    raise SmiError(
                        'float evaluation error: %s' % exc
                    )
            elif displayHintType == 'o' and (value.startswith('0') or value.startswith('-0')):
                try:
                    return base.prettyIn(self, int(value, 8))
                except Exception as exc:
                    raise SmiError(
                        'octal evaluation error: %s' % exc
                    )
            elif displayHintType == 'b' and (value.startswith('B') or value.startswith('-B')):
                negative = value.startswith('-')
                if negative:
                    value = value[2:]
                else:
                    value = value[1:]
                value = [x != '0' and 1 or 0 for x in value]
                binValue = 0
                while value:
                    binValue <<= value[0]
                    del value[0]
                return base.prettyIn(self, binValue)
            else:
                raise SmiError(
                    'Unsupported numeric type spec "%s" at %s' % (displayHintType, self.__class__.__name__)
                )

        elif self.displayHint and self.__octetString.isSuperTypeOf(self, matchConstraints=False):
            numBase = {
                'x': 16,
                'd': 10,
                'o': 8
            }
            numDigits = {
                'x': octets.str2octs(string.hexdigits),
                'o': octets.str2octs(string.octdigits),
                'd': octets.str2octs(string.digits)
            }

            # how do we know if object is initialized with display-hint
            # formatted text? based on "text" input maybe?
            # That boils down to `str` object on Py3 or `unicode` on Py2.
            if octets.isStringType(value) and not octets.isOctetsType(value):
                value = base.prettyIn(self, value)
            else:
                return base.prettyIn(self, value)

            outputValue = octets.str2octs('')
            runningValue = value
            displayHint = self.displayHint

            while runningValue and displayHint:
                # 1 this information is totally lost, just fail explicitly
                if displayHint[0] == '*':
                    raise SmiError(
                        'Can\'t parse "*" in DISPLAY-HINT (%s)' % self.__class__.__name__
                    )

                # 2 this becomes ambiguous when it comes to rendered value
                octetLength = ''
                while displayHint and displayHint[0] in string.digits:
                    octetLength += displayHint[0]
                    displayHint = displayHint[1:]

                # length is mandatory but people ignore that
                if not octetLength:
                    octetLength = len(runningValue)

                try:
                    octetLength = int(octetLength)
                except Exception:
                    raise SmiError(
                        'Bad octet length: %s' % octetLength
                    )

                if not displayHint:
                    raise SmiError(
                        'Short octet length: %s' % self.displayHint
                    )

                # 3
                displayFormat = displayHint[0]
                displayHint = displayHint[1:]

                # 4 this is the lifesaver -- we could use it as an anchor
                if displayHint and displayHint[0] not in string.digits and displayHint[0] != '*':
                    displaySep = displayHint[0]
                    displayHint = displayHint[1:]
                else:
                    displaySep = ''

                # 5 is probably impossible to support

                if displayFormat in ('a', 't'):
                    outputValue += runningValue[:octetLength]
                elif displayFormat in numBase:
                    if displaySep:
                        guessedOctetLength = runningValue.find(octets.str2octs(displaySep))
                        if guessedOctetLength == -1:
                            guessedOctetLength = len(runningValue)
                    else:
                        for idx in range(len(runningValue)):
                            if runningValue[idx] not in numDigits[displayFormat]:
                                guessedOctetLength = idx
                                break
                        else:
                            guessedOctetLength = len(runningValue)

                    try:
                        num = int(octets.octs2str(runningValue[:guessedOctetLength]), numBase[displayFormat])
                    except Exception as exc:
                        raise SmiError(
                            'Display format eval failure: %s: %s'
                            % (runningValue[:guessedOctetLength], exc)
                        )

                    num_as_bytes = []
                    if num:
                        while num:
                            num_as_bytes.append(num & 0xFF)
                            num >>= 8
                    else:
                        num_as_bytes = [0]

                    while len(num_as_bytes) < octetLength:
                        num_as_bytes.append(0)

                    num_as_bytes.reverse()

                    outputValue += octets.ints2octs(num_as_bytes)

                    if displaySep:
                        guessedOctetLength += 1

                    octetLength = guessedOctetLength
                else:
                    raise SmiError(
                        'Unsupported display format char: %s' %
                        displayFormat
                    )

                runningValue = runningValue[octetLength:]

                if not displayHint:
                    displayHint = self.displayHint

            return base.prettyIn(self, outputValue)

        else:
            return base.prettyIn(self, value)


class DisplayString(TextualConvention, OctetString):
    status = "current"
    displayHint = "255a"
    subtypeSpec = OctetString.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueSizeConstraint(0, 255),
    )

    if mibBuilder.loadTexts:
        description = """\
Represents textual information taken from the NVT ASCII character set, as
defined in pages 4, 10-11 of RFC 854. To summarize RFC 854, the NVT ASCII
repertoire specifies: - the use of character codes 0-127 (decimal) - the
graphics characters (32-126) are interpreted as US ASCII - NUL, LF, CR, BEL,
BS, HT, VT and FF have the special meanings specified in RFC 854 - the other 25
codes have no standard interpretation - the sequence 'CR LF' means newline -
the sequence 'CR NUL' means carriage-return - an 'LF' not preceded by a 'CR'
means moving to the same column on the next line. - the sequence 'CR x' for any
x other than LF or NUL is illegal. (Note that this also means that a string may
end with either 'CR LF' or 'CR NUL', but not with CR.) Any object defined using
this syntax may not exceed 255 characters in length.
"""


class PhysAddress(TextualConvention, OctetString):
    status = "current"
    displayHint = "1x:"
    if mibBuilder.loadTexts:
        description = """\
Represents media- or physical-level addresses.
"""


class MacAddress(TextualConvention, OctetString):
    status = "current"
    displayHint = "1x:"
    subtypeSpec = OctetString.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueSizeConstraint(6, 6),
    )
    fixedLength = 6

    if mibBuilder.loadTexts:
        description = """\
Represents an 802 MAC address represented in the `canonical' order defined by
IEEE 802.1a, i.e., as if it were transmitted least significant bit first, even
though 802.5 (in contrast to other 802.x protocols) requires MAC addresses to
be transmitted most significant bit first.
"""


class TruthValue(TextualConvention, Integer32):
    status = "current"
    subtypeSpec = Integer32.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        SingleValueConstraint(
            *(1,
              2)
        )
    )
    namedValues = NamedValues(
        *(("false", 2),
          ("true", 1))
    )

    if mibBuilder.loadTexts:
        description = """\
Represents a boolean value.
"""


class TestAndIncr(TextualConvention, Integer32):
    status = "current"
    subtypeSpec = Integer32.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueRangeConstraint(0, 2147483647),
    )

    if mibBuilder.loadTexts:
        description = """\
Represents integer-valued information used for atomic operations. When the
management protocol is used to specify that an object instance having this
syntax is to be modified, the new value supplied via the management protocol
must precisely match the value presently held by the instance. If not, the
management protocol set operation fails with an error of `inconsistentValue'.
Otherwise, if the current value is the maximum value of 2^31-1 (2147483647
decimal), then the value held by the instance is wrapped to zero; otherwise,
the value held by the instance is incremented by one. (Note that regardless of
whether the management protocol set operation succeeds, the variable- binding
in the request and response PDUs are identical.) The value of the ACCESS clause
for objects having this syntax is either `read-write' or `read-create'. When an
instance of a columnar object having this syntax is created, any value may be
supplied via the management protocol. When the network management portion of
the system is re- initialized, the value of every object instance having this
syntax must either be incremented from its value prior to the re-
initialization, or (if the value prior to the re- initialization is unknown) be
set to a pseudo-randomly generated value.
"""
    defaultValue = 0

    def setValue(self, value):
        if value is not None:
            if value != self:
                raise InconsistentValueError()
            value += 1
            if value > 2147483646:
                value = 0
        if value is None:
            value = univ.noValue
        return self.clone(value)


class AutonomousType(TextualConvention, ObjectIdentifier):
    status = "current"
    if mibBuilder.loadTexts:
        description = """\
Represents an independently extensible type identification value. It may, for
example, indicate a particular sub-tree with further MIB definitions, or define
a particular type of protocol or hardware.
"""


class InstancePointer(TextualConvention, ObjectIdentifier):
    status = "obsolete"
    if mibBuilder.loadTexts:
        description = """\
A pointer to either a specific instance of a MIB object or a conceptual row of
a MIB table in the managed device. In the latter case, by convention, it is the
name of the particular instance of the first accessible columnar object in the
conceptual row. The two uses of this textual convention are replaced by
VariablePointer and RowPointer, respectively.
"""


class VariablePointer(TextualConvention, ObjectIdentifier):
    status = "current"
    if mibBuilder.loadTexts:
        description = """\
A pointer to a specific object instance. For example, sysContact.0 or
ifInOctets.3.
"""


class RowPointer(TextualConvention, ObjectIdentifier):
    status = "current"
    if mibBuilder.loadTexts:
        description = """\
Represents a pointer to a conceptual row. The value is the name of the instance
of the first accessible columnar object in the conceptual row. For example,
ifIndex.3 would point to the 3rd row in the ifTable (note that if ifIndex were
not-accessible, then ifDescr.3 would be used instead).
"""


class RowStatus(TextualConvention, Integer):
    """A special kind of scalar MIB variable responsible for
       MIB table row creation/destruction.
    """
    status = "current"
    subtypeSpec = Integer.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        SingleValueConstraint(
            *(0,
              1,
              2,
              3,
              4,
              5,
              6)
        )
    )
    namedValues = NamedValues(
        *(("notExists", 0),
          ("active", 1),
          ("createAndGo", 4),
          ("createAndWait", 5),
          ("destroy", 6),
          ("notInService", 2),
          ("notReady", 3))
    )

    if mibBuilder.loadTexts:
        description = """\
    The RowStatus textual convention is used to manage the creation and deletion of
    conceptual rows, and is used as the value of the SYNTAX clause for the status
    column of a conceptual row (as described in Section 7.7.1 of [2].) The status
    column has six defined values: - `active', which indicates that the conceptual
    row is available for use by the managed device; - `notInService', which
    indicates that the conceptual row exists in the agent, but is unavailable for
    use by the managed device (see NOTE below); 'notInService' has no implication
    regarding the internal consistency of the row, availability of resources, or
    consistency with the current state of the managed device; - `notReady', which
    indicates that the conceptual row exists in the agent, but is missing
    information necessary in order to be available for use by the managed device
    (i.e., one or more required columns in the conceptual row have not been
    instanciated); - `createAndGo', which is supplied by a management station
    wishing to create a new instance of a conceptual row and to have its status
    automatically set to active, making it available for use by the managed device;
    - `createAndWait', which is supplied by a management station wishing to create
    a new instance of a conceptual row (but not make it available for use by the
    managed device); and, - `destroy', which is supplied by a management station
    wishing to delete all of the instances associated with an existing conceptual
    row. Whereas five of the six values (all except `notReady') may be specified in
    a management protocol set operation, only three values will be returned in
    response to a management protocol retrieval operation: `notReady',
    `notInService' or `active'. That is, when queried, an existing conceptual row
    has only three states: it is either available for use by the managed device
    (the status column has value `active'); it is not available for use by the
    managed device, though the agent has sufficient information to attempt to make
    it so (the status column has value `notInService'); or, it is not available for
    use by the managed device, and an attempt to make it so would fail because the
    agent has insufficient information (the state column has value `notReady').
    NOTE WELL This textual convention may be used for a MIB table, irrespective of
    whether the values of that table's conceptual rows are able to be modified
    while it is active, or whether its conceptual rows must be taken out of service
    in order to be modified. That is, it is the responsibility of the DESCRIPTION
    clause of the status column to specify whether the status column must not be
    `active' in order for the value of some other column of the same conceptual row
    to be modified. If such a specification is made, affected columns may be
    changed by an SNMP set PDU if the RowStatus would not be equal to `active'
    either immediately before or after processing the PDU. In other words, if the
    PDU also contained a varbind that would change the RowStatus value, the column
    in question may be changed if the RowStatus was not equal to `active' as the
    PDU was received, or if the varbind sets the status to a value other than
    'active'. Also note that whenever any elements of a row exist, the RowStatus
    column must also exist. To summarize the effect of having a conceptual row with
    a status column having a SYNTAX clause value of RowStatus, consider the
    following state diagram: STATE
    +--------------+-----------+-------------+------------- | A | B | C | D |
    |status col.|status column| |status column | is | is |status column ACTION
    |does not exist| notReady | notInService| is active
    --------------+--------------+-----------+-------------+------------- set
    status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or |
    entValue| Value| Value createAndGo |inconsistent- | | | | Value| | |
    --------------+--------------+-----------+-------------+------------- set
    status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or |
    entValue| Value| Value createAndWait |wrongValue | | |
    --------------+--------------+-----------+-------------+------------- set
    status |inconsistent- |inconsist- |noError |noError column to | Value|
    entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D
    --------------+--------------+-----------+-------------+------------- set
    status |inconsistent- |inconsist- |noError |noError ->C column to | Value|
    entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6
    --------------+--------------+-----------+-------------+------------- set
    status |noError |noError |noError |noError ->A column to | | | | or destroy |
    ->A| ->A| ->A|see 7
    --------------+--------------+-----------+-------------+------------- set any
    other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1|
    ->C| ->D --------------+--------------+-----------+-------------+-------------
    (1) goto B or C, depending on information available to the agent. (2) if other
    variable bindings included in the same PDU, provide values for all columns
    which are missing but required, and all columns have acceptable values, then
    return noError and goto D. (3) if other variable bindings included in the same
    PDU, provide legal values for all columns which are missing but required, then
    return noError and goto C. (4) at the discretion of the agent, the return value
    may be either: inconsistentName: because the agent does not choose to create
    such an instance when the corresponding RowStatus instance does not exist, or
    inconsistentValue: if the supplied value is inconsistent with the state of some
    other MIB object's value, or noError: because the agent chooses to create the
    instance. If noError is returned, then the instance of the status column must
    also be created, and the new state is B or C, depending on the information
    available to the agent. If inconsistentName or inconsistentValue is returned,
    the row remains in state A. (5) depending on the MIB definition for the
    column/table, either noError or inconsistentValue may be returned. (6) the
    return value can indicate one of the following errors: wrongValue: because the
    agent does not support notInService (e.g., an agent which does not support
    createAndWait), or inconsistentValue: because the agent is unable to take the
    row out of service at this time, perhaps because it is in use and cannot be de-
    activated. (7) the return value can indicate the following error:
    inconsistentValue: because the agent is unable to remove the row at this time,
    perhaps because it is in use and cannot be de-activated. (8) the transition to
    D can fail, e.g., if the values of the conceptual row are inconsistent, then
    the error code would be inconsistentValue. NOTE: Other processing of (this and
    other varbinds of) the set request may result in a response other than noError
    being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation
    There are four potential interactions when creating a conceptual row: selecting
    an instance-identifier which is not in use; creating the conceptual row;
    initializing any objects for which the agent does not supply a default; and,
    making the conceptual row available for use by the managed device. Interaction
    1: Selecting an Instance-Identifier The algorithm used to select an instance-
    identifier varies for each conceptual row. In some cases, the instance-
    identifier is semantically significant, e.g., the destination address of a
    route, and a management station selects the instance-identifier according to
    the semantics. In other cases, the instance-identifier is used solely to
    distinguish conceptual rows, and a management station without specific
    knowledge of the conceptual row might examine the instances present in order to
    determine an unused instance-identifier. (This approach may be used, but it is
    often highly sub-optimal; however, it is also a questionable practice for a
    naive management station to attempt conceptual row creation.) Alternately, the
    MIB module which defines the conceptual row might provide one or more objects
    which provide assistance in determining an unused instance-identifier. For
    example, if the conceptual row is indexed by an integer-value, then an object
    having an integer-valued SYNTAX clause might be defined for such a purpose,
    allowing a management station to issue a management protocol retrieval
    operation. In order to avoid unnecessary collisions between competing
    management stations, `adjacent' retrievals of this object should be different.
    Finally, the management station could select a pseudo-random number to use as
    the index. In the event that this index was already in use and an
    inconsistentValue was returned in response to the management protocol set
    operation, the management station should simply select a new pseudo-random
    number and retry the operation. A MIB designer should choose between the two
    latter algorithms based on the size of the table (and therefore the efficiency
    of each algorithm). For tables in which a large number of entries are expected,
    it is recommended that a MIB object be defined that returns an acceptable index
    for creation. For tables with small numbers of entries, it is recommended that
    the latter pseudo-random index mechanism be used. Interaction 2: Creating the
    Conceptual Row Once an unused instance-identifier has been selected, the
    management station determines if it wishes to create and activate the
    conceptual row in one transaction or in a negotiated set of interactions.
    Interaction 2a: Creating and Activating the Conceptual Row The management
    station must first determine the column requirements, i.e., it must determine
    those columns for which it must or must not provide values. Depending on the
    complexity of the table and the management station's knowledge of the agent's
    capabilities, this determination can be made locally by the management station.
    Alternately, the management station issues a management protocol get operation
    to examine all columns in the conceptual row that it wishes to create. In
    response, for each column, there are three possible outcomes: - a value is
    returned, indicating that some other management station has already created
    this conceptual row. We return to interaction 1. - the exception
    `noSuchInstance' is returned, indicating that the agent implements the object-
    type associated with this column, and that this column in at least one
    conceptual row would be accessible in the MIB view used by the retrieval were
    it to exist. For those columns to which the agent provides read-create access,
    the `noSuchInstance' exception tells the management station that it should
    supply a value for this column when the conceptual row is to be created. - the
    exception `noSuchObject' is returned, indicating that the agent does not
    implement the object-type associated with this column or that there is no
    conceptual row for which this column would be accessible in the MIB view used
    by the retrieval. As such, the management station can not issue any management
    protocol set operations to create an instance of this column. Once the column
    requirements have been determined, a management protocol set operation is
    accordingly issued. This operation also sets the new instance of the status
    column to `createAndGo'. When the agent processes the set operation, it
    verifies that it has sufficient information to make the conceptual row
    available for use by the managed device. The information available to the agent
    is provided by two sources: the management protocol set operation which creates
    the conceptual row, and, implementation-specific defaults supplied by the agent
    (note that an agent must provide implementation-specific defaults for at least
    those objects which it implements as read-only). If there is sufficient
    information available, then the conceptual row is created, a `noError' response
    is returned, the status column is set to `active', and no further interactions
    are necessary (i.e., interactions 3 and 4 are skipped). If there is
    insufficient information, then the conceptual row is not created, and the set
    operation fails with an error of `inconsistentValue'. On this error, the
    management station can issue a management protocol retrieval operation to
    determine if this was because it failed to specify a value for a required
    column, or, because the selected instance of the status column already existed.
    In the latter case, we return to interaction 1. In the former case, the
    management station can re-issue the set operation with the additional
    information, or begin interaction 2 again using `createAndWait' in order to
    negotiate creation of the conceptual row. NOTE WELL Regardless of the method
    used to determine the column requirements, it is possible that the management
    station might deem a column necessary when, in fact, the agent will not allow
    that particular columnar instance to be created or written. In this case, the
    management protocol set operation will fail with an error such as `noCreation'
    or `notWritable'. In this case, the management station decides whether it needs
    to be able to set a value for that particular columnar instance. If not, the
    management station re-issues the management protocol set operation, but without
    setting a value for that particular columnar instance; otherwise, the
    management station aborts the row creation algorithm. Interaction 2b:
    Negotiating the Creation of the Conceptual Row The management station issues a
    management protocol set operation which sets the desired instance of the status
    column to `createAndWait'. If the agent is unwilling to process a request of
    this sort, the set operation fails with an error of `wrongValue'. (As a
    consequence, such an agent must be prepared to accept a single management
    protocol set operation, i.e., interaction 2a above, containing all of the
    columns indicated by its column requirements.) Otherwise, the conceptual row is
    created, a `noError' response is returned, and the status column is immediately
    set to either `notInService' or `notReady', depending on whether it has
    sufficient information to (attempt to) make the conceptual row available for
    use by the managed device. If there is sufficient information available, then
    the status column is set to `notInService'; otherwise, if there is insufficient
    information, then the status column is set to `notReady'. Regardless, we
    proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The
    management station must now determine the column requirements. It issues a
    management protocol get operation to examine all columns in the created
    conceptual row. In the response, for each column, there are three possible
    outcomes: - a value is returned, indicating that the agent implements the
    object-type associated with this column and had sufficient information to
    provide a value. For those columns to which the agent provides read-create
    access (and for which the agent allows their values to be changed after their
    creation), a value return tells the management station that it may issue
    additional management protocol set operations, if it desires, in order to
    change the value associated with this column. - the exception `noSuchInstance'
    is returned, indicating that the agent implements the object-type associated
    with this column, and that this column in at least one conceptual row would be
    accessible in the MIB view used by the retrieval were it to exist. However, the
    agent does not have sufficient information to provide a value, and until a
    value is provided, the conceptual row may not be made available for use by the
    managed device. For those columns to which the agent provides read-create
    access, the `noSuchInstance' exception tells the management station that it
    must issue additional management protocol set operations, in order to provide a
    value associated with this column. - the exception `noSuchObject' is returned,
    indicating that the agent does not implement the object-type associated with
    this column or that there is no conceptual row for which this column would be
    accessible in the MIB view used by the retrieval. As such, the management
    station can not issue any management protocol set operations to create an
    instance of this column. If the value associated with the status column is
    `notReady', then the management station must first deal with all
    `noSuchInstance' columns, if any. Having done so, the value of the status
    column becomes `notInService', and we proceed to interaction 4. Interaction 4:
    Making the Conceptual Row Available Once the management station is satisfied
    with the values associated with the columns of the conceptual row, it issues a
    management protocol set operation to set the status column to `active'. If the
    agent has sufficient information to make the conceptual row available for use
    by the managed device, the management protocol set operation succeeds (a
    `noError' response is returned). Otherwise, the management protocol set
    operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual
    row having a status column with value `notInService' or `notReady' is
    unavailable to the managed device. As such, it is possible for the managed
    device to create its own instances during the time between the management
    protocol set operation which sets the status column to `createAndWait' and the
    management protocol set operation which sets the status column to `active'. In
    this case, when the management protocol set operation is issued to set the
    status column to `active', the values held in the agent supersede those used by
    the managed device. If the management station is prevented from setting the
    status column to `active' (e.g., due to management station or network failure)
    the conceptual row will be left in the `notInService' or `notReady' state,
    consuming resources indefinitely. The agent must detect conceptual rows that
    have been in either state for an abnormally long period of time and remove
    them. It is the responsibility of the DESCRIPTION clause of the status column
    to indicate what an abnormally long period of time would be. This period of
    time should be long enough to allow for human response time (including `think
    time') between the creation of the conceptual row and the setting of the status
    to `active'. In the absence of such information in the DESCRIPTION clause, it
    is suggested that this period be approximately 5 minutes in length. This
    removal action applies not only to newly-created rows, but also to previously
    active rows which are set to, and left in, the notInService state for a
    prolonged period exceeding that which is considered normal for such a
    conceptual row. Conceptual Row Suspension When a conceptual row is `active',
    the management station may issue a management protocol set operation which sets
    the instance of the status column to `notInService'. If the agent is unwilling
    to do so, the set operation fails with an error of `wrongValue' or
    `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and
    a `noError' response is returned. It is the responsibility of the DESCRIPTION
    clause of the status column to indicate under what circumstances the status
    column should be taken out of service (e.g., in order for the value of some
    other column of the same conceptual row to be modified). Conceptual Row
    Deletion For deletion of conceptual rows, a management protocol set operation
    is issued which sets the instance of the status column to `destroy'. This
    request may be made regardless of the current value of the status column (e.g.,
    it is possible to delete conceptual rows which are either `notReady',
    `notInService' or `active'.) If the operation succeeds, then all instances
    associated with the conceptual row are immediately removed.
    """

    # Known row states
    (stNotExists, stActive, stNotInService,
     stNotReady, stCreateAndGo, stCreateAndWait,
     stDestroy) = list(range(7))

    # States transition matrix (see RFC-1903)
    STATE_MATRIX = {
        # (new-state, current-state)  ->  (error, new-state)
        (stCreateAndGo, stNotExists): (RowCreationWanted, stActive),
        (stCreateAndGo, stNotReady): (InconsistentValueError, stNotReady),
        (stCreateAndGo, stNotInService): (InconsistentValueError, stNotInService),
        (stCreateAndGo, stActive): (InconsistentValueError, stActive),
        #
        (stCreateAndWait, stNotExists): (RowCreationWanted, stNotReady),
        (stCreateAndWait, stNotReady): (InconsistentValueError, stNotReady),
        (stCreateAndWait, stNotInService): (InconsistentValueError, stNotInService),
        (stCreateAndWait, stActive): (InconsistentValueError, stActive),
        #
        (stActive, stNotExists): (InconsistentValueError, stNotExists),
        (stActive, stNotReady): (RowConsistencyWanted, stActive),
        (stActive, stNotInService): (RowConsistencyWanted, stActive),
        (stActive, stActive): (None, stActive),
        #
        (stNotInService, stNotExists): (InconsistentValueError, stNotExists),
        (stNotInService, stNotReady): (None, stNotReady),
        (stNotInService, stNotInService): (None, stNotInService),
        (stNotInService, stActive): (None, stActive),
        #
        (stDestroy, stNotExists): (RowDestructionWanted, stNotExists),
        (stDestroy, stNotReady): (RowDestructionWanted, stNotExists),
        (stDestroy, stNotInService): (RowDestructionWanted, stNotExists),
        (stDestroy, stActive): (RowDestructionWanted, stNotExists),
        # This is used on instantiation
        (stNotExists, stNotExists): (None, stNotExists)
    }

    def setValue(self, value):
        if value is None:
            value = univ.noValue

        value = self.clone(value)

        # Run through states transition matrix,
        # resolve new instance value
        excValue, newState = self.STATE_MATRIX.get(
            (value.hasValue() and value or self.stNotExists,
             self.hasValue() and self or self.stNotExists),
            (MibOperationError, None)
        )

        if newState is None:
            newState = univ.noValue

        newState = self.clone(newState)

        debug.logger & debug.FLAG_INS and debug.logger(
            'RowStatus state change from %r to %r produced new state %r, error indication %r' % (
                self, value, newState, excValue))

        if excValue is not None:
            excValue = excValue(
                msg='Exception at row state transition from %r to %r yields state %r and exception' % (
                    self, value, newState), syntax=newState
            )
            raise excValue

        return newState


class TimeStamp(TextualConvention, TimeTicks):
    status = "current"
    if mibBuilder.loadTexts:
        description = """\
The value of the sysUpTime object at which a specific occurrence happened. The
specific occurrence must be defined in the description of any object defined
using this type. If sysUpTime is reset to zero as a result of a re-
initialization of the network management (sub)system, then the values of all
TimeStamp objects are also reset. However, after approximately 497 days without
a re- initialization, the sysUpTime object will reach 2^^32-1 and then
increment around to zero; in this case, existing values of TimeStamp objects do
not change. This can lead to ambiguities in the value of TimeStamp objects.
"""


class TimeInterval(TextualConvention, Integer32):
    status = "current"
    subtypeSpec = Integer32.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueRangeConstraint(0, 2147483647),
    )

    if mibBuilder.loadTexts:
        description = """\
A period of time, measured in units of 0.01 seconds.
"""


class DateAndTime(TextualConvention, OctetString):
    status = "current"
    displayHint = "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"
    subtypeSpec = OctetString.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueSizeConstraint(8, 8),
        ValueSizeConstraint(11, 11),
    )

    if mibBuilder.loadTexts:
        description = """\
A date-time specification. field octets contents range ----- ------ --------
----- 1 1-2 year* 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6
minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8 deci-seconds 0..9
8 9 direction from UTC '+' / '-' 9 10 hours from UTC* 0..13 10 11 minutes from
UTC 0..59 * Notes: - the value of year is in network-byte order - daylight
saving time in New Zealand is +13 For example, Tuesday May 26, 1992 at 1:30:15
PM EDT would be displayed as: 1992-5-26,13:30:15.0,-4:0 Note that if only local
time is known, then timezone information (fields 8-10) is not present.
"""


class StorageType(TextualConvention, Integer32):
    status = "current"
    subtypeSpec = Integer32.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        SingleValueConstraint(
            *(1,
              2,
              3,
              4,
              5)
        )
    )
    namedValues = NamedValues(
        *(("nonVolatile", 3),
          ("other", 1),
          ("permanent", 4),
          ("readOnly", 5),
          ("volatile", 2))
    )

    if mibBuilder.loadTexts:
        description = """\
Describes the memory realization of a conceptual row. A row which is
volatile(2) is lost upon reboot. A row which is either nonVolatile(3),
permanent(4) or readOnly(5), is backed up by stable storage. A row which is
permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot
be changed nor deleted. If the value of an object with this syntax is either
permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is
either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be
permanent(4) or readOnly(5). (All illegal modifications result in a
'wrongValue' error.) Every usage of this textual convention is required to
specify the columnar objects which a permanent(4) row must at a minimum allow
to be writable.
"""


class TDomain(TextualConvention, ObjectIdentifier):
    status = "current"
    if mibBuilder.loadTexts:
        description = """\
Denotes a kind of transport service. Some possible values, such as
snmpUDPDomain, are defined in the SNMPv2-TM MIB module. Other possible values
are defined in other MIB modules.
"""


class TAddress(TextualConvention, OctetString):
    status = "current"
    subtypeSpec = OctetString.subtypeSpec
    subtypeSpec += ConstraintsUnion(
        ValueSizeConstraint(1, 255),
    )

    if mibBuilder.loadTexts:
        description = """\
Denotes a transport service address. A TAddress value is always interpreted
within the context of a TDomain value. Thus, each definition of a TDomain value
must be accompanied by a definition of a textual convention for use with that
TDomain. Some possible textual conventions, such as SnmpUDPAddress for
snmpUDPDomain, are defined in the SNMPv2-TM MIB module. Other possible textual
conventions are defined in other MIB modules.
"""


mibBuilder.exportSymbols(
    "SNMPv2-TC",
    **{"TextualConvention": TextualConvention,
       "DisplayString": DisplayString,
       "PhysAddress": PhysAddress,
       "MacAddress": MacAddress,
       "TruthValue": TruthValue,
       "TestAndIncr": TestAndIncr,
       "AutonomousType": AutonomousType,
       "InstancePointer": InstancePointer,
       "VariablePointer": VariablePointer,
       "RowPointer": RowPointer,
       "RowStatus": RowStatus,
       "TimeStamp": TimeStamp,
       "TimeInterval": TimeInterval,
       "DateAndTime": DateAndTime,
       "StorageType": StorageType,
       "TDomain": TDomain,
       "TAddress": TAddress}
)