Disable pypy build in Travis

Because it stopped working.

.travis.yml

@@ -2,22 +2,10 @@ language: python
 cache: pip
 matrix:
   include:
-  - os: linux
-    dist: xenial
-    sudo: false
-    python: '2.6'
   - os: linux
     dist: xenial
     sudo: false
     python: '2.7'
-  - os: linux
-    dist: xenial
-    sudo: false
-    python: '3.2'
-  - os: linux
-    dist: xenial
-    sudo: false
-    python: '3.3'
   - os: linux
     dist: xenial
     sudo: false
@@ -38,14 +26,14 @@ matrix:
     dist: xenial
     sudo: false
     python: 'nightly'
-  - os: linux
-    dist: xenial
-    sudo: false
-    python: 'pypy'
-  - os: linux
-    dist: xenial
-    sudo: false
-    python: 'pypy3'
+#  - os: linux
+#    dist: xenial
+#    sudo: false
+#    python: 'pypy'
+#  - os: linux
+#    dist: xenial
+#    sudo: false
+#    python: 'pypy3'
 install:
   - pip install -r requirements.txt -r devel-requirements.txt -r extra-requirements.txt
   - pip install -e .

CHANGES.txt

@@ -5,9 +5,11 @@ Revision 5.0.0, released 2018-10-??
 - SNMPv3 crypto operations that require external dependencies
   made dependent on the optional external
   package -- pysnmpcrypto.
+
 - By switching to pysnmpcrypto, pysnmp effectively migrates from
   PyCryptodomex to pyca/cryptography whenever available on the
   platform.
+
 - Many really old backward-compatibility code snippets removed.
   Most importantly:
   
@@ -19,13 +21,22 @@ Revision 5.0.0, released 2018-10-??
 - The MIB instrumentation API overhauled in backward incompatible
   way:
 
-      - MIB instrumentation methods signatures simplified to accept
-        just var-binds (as var-arg), the rest of the parameters packed
-        into opaque kwargs
-      - CommandResponder application passes `snmpEngine` and optionally
-        user-supplied `cbCtx` object throughout the MIB instrumentation
-        methods. The goal is to let MIB objects access/modify whatever
-        custom Python objects they need while being called back.
+  * MIB instrumentation methods signatures simplified to accept
+    just var-binds (as var-arg), the rest of the parameters packed
+    into opaque kwargs
+
+  * The `readVars`, `readNextVars` and `writeVars` methods of MIB
+    instrumentation controller return immediately and deliver their
+    results via a call back.
+
+  * CommandResponder application passes `snmpEngine` and optionally
+    user-supplied `cbCtx` object throughout the MIB instrumentation
+    methods. The goal is to let MIB objects access/modify whatever
+    custom Python objects they need while being called back.
+
+  * CommandResponder refactored to facilitate asynchronous
+    MIB instrumentation routines.
+
 - The high-level API (`hlapi`) extended to cover lightweight SNMP v1arch
   in hope to ease the use of packet-level SNMP API.
 
@@ -41,16 +52,22 @@ Revision 5.0.0, released 2018-10-??
   automation around building well-formed SNMP messages is and mediating
   differences between SNMP versions is not present in this new `v1arch`
   layer.
+
 - The signature of the hlapi `.sendNotification()` call has changed
   to accept `*varBinds` instead of a sequence of `varBinds`. The rationale
   is to unify this method call with similar methods of CommandGenerator.
   This change should not compromise backward compatibility with pysnmp 4.
 
-Revision 4.4.7, released 2018-09-XX
+Revision 4.4.7, released 2018-11-XX
 -----------------------------------
 
+- Exposed ASN.1 `Null` type through `rfc1902` module for convenience.
+- Use `compile()` before `exec`'ing MIB modules to attach filename to
+  the stack frames (ultimately shown in traceback/debugger)
 - Fixed hlapi/v3arch transport target caching to ensure transport targets
   are different even if just timeout/retries options differ
+- Fixed hlapi LCD configurator to include `contextName`. Prior to this fix
+  sending SNMPv3 TRAP with non-default `contextName` would fail.
 
 Revision 4.4.6, released 2018-09-13
 -----------------------------------

docs/source/docs/api-reference.rst

@@ -441,6 +441,20 @@ data description language. PySNMP types are derived from
 .. toctree::
    :maxdepth: 2
 
+.. _null:
+
+Null type
++++++++++
+
+.. autoclass:: pysnmp.proto.rfc1902.Null(initializer)
+   :members:
+
+.. note::
+
+   The `NULL` type actually belongs to the base ASN.1 types. It is not defined
+   in :RFC:`1902#section-2` as an SNMP type. The `Null` type is exposed through
+   `rfc1902` module just for convenience.
+
 .. _integer32:
 
 Integer32 type

examples/smi/agent/custom-managed-object.py

@@ -51,13 +51,23 @@ if __name__ == '__main__':
 
     mibInstrum = instrum.MibInstrumController(mibBuilder)
 
+    def cbFun(varBinds, **context):
+        for oid, val in varBinds:
+            if exval.endOfMib.isSameTypeWith(val):
+                context['state']['stop'] = True
+            print('%s = %s' % ('.'.join([str(x) for x in oid]), not val.isValue and 'N/A' or val.prettyPrint()))
+
+        context['state']['varBinds'] = varBinds
+
+    context = {
+        'cbFun': cbFun,
+        'state': {
+            'varBinds': [((1, 3, 6), None)],
+            'stop': False
+        }
+    }
+
     print('Remote manager read access to MIB instrumentation (table walk)')
-
-    varBinds = [((), None)]
-
-    while True:
-        varBinds = mibInstrum.readNextVars(*varBinds)
-        oid, val = varBinds[0]
-        if exval.endOfMib.isSameTypeWith(val):
-            break
-        print(oid, val.prettyPrint())
+    while not context['state']['stop']:
+        mibInstrum.readNextVars(*context['state']['varBinds'], **context)
+    print('done')

examples/smi/agent/operations-on-managed-objects.py

@@ -26,24 +26,40 @@ snmpCommunityEntry, = mibBuilder.importSymbols(
 instanceId = snmpCommunityEntry.getInstIdFromIndices('my-router')
 print('done')
 
+
+def cbFun(varBinds, **context):
+    for oid, val in varBinds:
+        print('%s = %s' % ('.'.join([str(x) for x in oid]), not val.isValue and 'N/A' or val.prettyPrint()))
+
 print('Create/update SNMP-COMMUNITY-MIB::snmpCommunityEntry table row: ')
-varBinds = mibInstrum.writeVars(
+mibInstrum.writeVars(
     (snmpCommunityEntry.name + (2,) + instanceId, 'mycomm'),
     (snmpCommunityEntry.name + (3,) + instanceId, 'mynmsname'),
-    (snmpCommunityEntry.name + (7,) + instanceId, 'volatile')
+    (snmpCommunityEntry.name + (7,) + instanceId, 'volatile'),
+    cbFun=cbFun
 )
-for oid, val in varBinds:
-    print('%s = %s' % ('.'.join([str(x) for x in oid]), not val.isValue and 'N/A' or val.prettyPrint()))
 print('done')
 
+
+def cbFun(varBinds, **context):
+    for oid, val in varBinds:
+        if exval.endOfMib.isSameTypeWith(val):
+            context['state']['stop'] = True
+        print('%s = %s' % ('.'.join([str(x) for x in oid]), not val.isValue and 'N/A' or val.prettyPrint()))
+
+    context['state']['varBinds'] = varBinds
+
+context = {
+    'cbFun': cbFun,
+    'state': {
+        'varBinds': [((1, 3, 6), None)],
+        'stop': False
+    }
+}
+
 print('Read whole MIB (table walk)')
-varBinds = [((), None)]
-while True:
-    varBinds = mibInstrum.readNextVars(*varBinds)
-    oid, val = varBinds[0]
-    if exval.endOfMib.isSameTypeWith(val):
-        break
-    print('%s = %s' % ('.'.join([str(x) for x in oid]), not val.isValue and 'N/A' or val.prettyPrint()))
+while not context['state']['stop']:
+    mibInstrum.readNextVars(*context['state']['varBinds'], **context)
 print('done')
 
 print('Unloading MIB modules...'),

examples/v3arch/asyncore/agent/cmdrsp/custom-mib-controller.py

@@ -54,7 +54,9 @@ snmpContext = context.SnmpContext(snmpEngine)
 # always echos request var-binds in response.
 class EchoMibInstrumController(instrum.AbstractMibInstrumController):
     def readVars(self, *varBinds, **context):
-        return [(ov[0], v2c.OctetString('You queried OID %s' % ov[0])) for ov in varBinds]
+        cbFun = context.get('cbFun')
+        if cbFun:
+            cbFun([(ov[0], v2c.OctetString('You queried OID %s' % ov[0])) for ov in varBinds], **context)
 
 
 # Create a custom Management Instrumentation Controller and register at

examples/v3arch/asyncore/agent/cmdrsp/implementing-scalar-mib-objects.py

@@ -56,7 +56,7 @@ MibScalar, MibScalarInstance = mibBuilder.importSymbols(
 
 class MyStaticMibScalarInstance(MibScalarInstance):
     # noinspection PyUnusedLocal,PyUnusedLocal
-    def getValue(self, name, idx):
+    def getValue(self, name, idx, **context):
         return self.getSyntax().clone(
             'Python %s running on a %s platform' % (sys.version, sys.platform)
         )

examples/v3arch/asyncore/proxy/command/ipv6-to-ipv4-conversion.py

@@ -96,7 +96,7 @@ class CommandResponder(cmdrsp.CommandResponderBase):
         v2c.GetNextRequestPDU.tagSet: cmdgen.NextCommandGeneratorSingleRun(),
         v2c.GetBulkRequestPDU.tagSet: cmdgen.BulkCommandGeneratorSingleRun()
     }
-    pduTypes = cmdGenMap.keys()  # This app will handle these PDUs
+    SUPPORTED_PDU_TYPES = cmdGenMap.keys()  # This app will handle these PDUs
 
     # SNMP request relay
     def handleMgmtOperation(self, snmpEngine, stateReference, contextName,

examples/v3arch/asyncore/proxy/command/v2c-to-v1-conversion.py

@@ -95,7 +95,7 @@ class CommandResponder(cmdrsp.CommandResponderBase):
         v2c.GetNextRequestPDU.tagSet: cmdgen.NextCommandGeneratorSingleRun(),
         v2c.GetBulkRequestPDU.tagSet: cmdgen.BulkCommandGeneratorSingleRun()
     }
-    pduTypes = cmdGenMap.keys()  # This app will handle these PDUs
+    SUPPORTED_PDU_TYPES = cmdGenMap.keys()  # This app will handle these PDUs
 
     # SNMP request relay
     def handleMgmtOperation(self, snmpEngine, stateReference, contextName,

examples/v3arch/asyncore/proxy/command/v2c-to-v3-conversion.py

@@ -95,7 +95,7 @@ class CommandResponder(cmdrsp.CommandResponderBase):
         v2c.GetNextRequestPDU.tagSet: cmdgen.NextCommandGeneratorSingleRun(),
         v2c.GetBulkRequestPDU.tagSet: cmdgen.BulkCommandGeneratorSingleRun()
     }
-    pduTypes = cmdGenMap.keys()  # This app will handle these PDUs
+    SUPPORTED_PDU_TYPES = cmdGenMap.keys()  # This app will handle these PDUs
 
     # SNMP request relay
     def handleMgmtOperation(self, snmpEngine, stateReference, contextName,

examples/v3arch/asyncore/proxy/command/v3-to-v2c-conversion.py

@@ -98,7 +98,7 @@ class CommandResponder(cmdrsp.CommandResponderBase):
         v2c.GetNextRequestPDU.tagSet: cmdgen.NextCommandGeneratorSingleRun(),
         v2c.GetBulkRequestPDU.tagSet: cmdgen.BulkCommandGeneratorSingleRun()
     }
-    pduTypes = cmdGenMap.keys()  # This app will handle these PDUs
+    SUPPORTED_PDU_TYPES = cmdGenMap.keys()  # This app will handle these PDUs
 
     # SNMP request relay
     def handleMgmtOperation(self, snmpEngine, stateReference, contextName,

pysnmp/carrier/asyncore/dgram/base.py

@@ -99,7 +99,7 @@ class DgramSocketTransport(AbstractSocketTransport):
         except socket.error:
             raise error.CarrierError('setsockopt() for IP_TRANSPARENT failed: %s' % sys.exc_info()[1])
         except OSError:
-            raise error.CarrierError('IP_TRANSPARENT socket option requires superusre previleges')
+            raise error.CarrierError('IP_TRANSPARENT socket option requires superuser priveleges')
 
         debug.logger & debug.flagIO and debug.logger('enableTransparent: %s option IP_TRANSPARENT on socket %s' % (flag and "enabled" or "disabled", self.socket.fileno()))
         return self

pysnmp/entity/config.py

@@ -422,7 +422,8 @@ def delContext(snmpEngine, contextName):
     vacmContextEntry, tblIdx = __cookVacmContextInfo(snmpEngine, contextName)
 
     snmpEngine.msgAndPduDsp.mibInstrumController.writeVars(
-        (vacmContextEntry.name + (2,) + tblIdx, 'destroy')
+        (vacmContextEntry.name + (2,) + tblIdx, 'destroy'),
+        ** dict(snmpEngine=snmpEngine)
     )
 
 
@@ -577,12 +578,13 @@ def addVacmUser(snmpEngine, securityModel, securityName, securityLevel,
 
 
 def delVacmUser(snmpEngine, securityModel, securityName, securityLevel,
-                readSubTree=(), writeSubTree=(), notifySubTree=()):
+                readSubTree=(), writeSubTree=(), notifySubTree=(),
+                contextName=null):
     (groupName, securityLevel, readView, writeView,
      notifyView) = __cookVacmUserInfo(snmpEngine, securityModel,
                                       securityName, securityLevel)
     delVacmGroup(snmpEngine, securityModel, securityName)
-    delVacmAccess(snmpEngine, groupName, null, securityModel, securityLevel)
+    delVacmAccess(snmpEngine, groupName, contextName, securityModel, securityLevel)
     if readSubTree:
         delVacmView(
             snmpEngine, readView, readSubTree
@@ -596,7 +598,6 @@ def delVacmUser(snmpEngine, securityModel, securityName, securityLevel,
             snmpEngine, notifyView, notifySubTree
         )
 
-
 # Notification target setup
 
 def __cookNotificationTargetInfo(snmpEngine, notificationName, paramsName,

pysnmp/entity/rfc3413/cmdrsp.py

@@ -15,26 +15,41 @@ from pysnmp import debug
 # 3.2
 class CommandResponderBase(object):
     acmID = 3  # default MIB access control method to use
-    pduTypes = ()
+    SUPPORTED_PDU_TYPES = ()
+    SMI_ERROR_MAP = {
+        pysnmp.smi.error.NoAccessError: 'noAccess',
+        pysnmp.smi.error.WrongTypeError: 'wrongType',
+        pysnmp.smi.error.WrongLengthError: 'wrongLength',
+        pysnmp.smi.error.WrongEncodingError: 'wrongEncoding',
+        pysnmp.smi.error.WrongValueError: 'wrongValue',
+        pysnmp.smi.error.NoCreationError: 'noCreation',
+        pysnmp.smi.error.InconsistentValueError: 'inconsistentValue',
+        pysnmp.smi.error.ResourceUnavailableError: 'resourceUnavailable',
+        pysnmp.smi.error.CommitFailedError: 'commitFailed',
+        pysnmp.smi.error.UndoFailedError: 'undoFailed',
+        pysnmp.smi.error.AuthorizationError: 'authorizationError',
+        pysnmp.smi.error.NotWritableError: 'notWritable',
+        pysnmp.smi.error.InconsistentNameError: 'inconsistentName'
+    }
 
     def __init__(self, snmpEngine, snmpContext, cbCtx=None):
         snmpEngine.msgAndPduDsp.registerContextEngineId(
-            snmpContext.contextEngineId, self.pduTypes, self.processPdu
+            snmpContext.contextEngineId, self.SUPPORTED_PDU_TYPES, self.processPdu
         )
         self.snmpContext = snmpContext
         self.cbCtx = cbCtx
         self.__pendingReqs = {}
 
-    def handleMgmtOperation(self, snmpEngine, stateReference,
-                            contextName, PDU, acCtx):
-        pass
-
     def close(self, snmpEngine):
         snmpEngine.msgAndPduDsp.unregisterContextEngineId(
-            self.snmpContext.contextEngineId, self.pduTypes
+            self.snmpContext.contextEngineId, self.SUPPORTED_PDU_TYPES
         )
         self.snmpContext = self.__pendingReqs = None
 
+    def releaseStateInformation(self, stateReference):
+        if stateReference in self.__pendingReqs:
+            del self.__pendingReqs[stateReference]
+
     def sendVarBinds(self, snmpEngine, stateReference,
                      errorStatus, errorIndex, varBinds):
         (messageProcessingModel,
@@ -106,10 +121,6 @@ class CommandResponderBase(object):
     _setRequestType = rfc1905.SetRequestPDU.tagSet
     _counter64Type = rfc1902.Counter64.tagSet
 
-    def releaseStateInformation(self, stateReference):
-        if stateReference in self.__pendingReqs:
-            del self.__pendingReqs[stateReference]
-
     def processPdu(self, snmpEngine, messageProcessingModel, securityModel,
                    securityName, securityLevel, contextEngineId, contextName,
                    pduVersion, PDU, maxSizeResponseScopedPDU, stateReference):
@@ -141,63 +152,11 @@ class CommandResponderBase(object):
 
         # 3.2.5
         varBinds = v2c.apiPDU.getVarBinds(PDU)
-        errorStatus, errorIndex = 'noError', 0
 
         debug.logger & debug.flagApp and debug.logger(
             'processPdu: stateReference %s, varBinds %s' % (stateReference, varBinds))
 
-        try:
-            self.handleMgmtOperation(snmpEngine, stateReference, contextName, PDU)
-
-        # SNMPv2 SMI exceptions
-        except pysnmp.smi.error.GenError:
-            errorIndication = sys.exc_info()[1]
-            debug.logger & debug.flagApp and debug.logger(
-                'processPdu: stateReference %s, errorIndication %s' % (stateReference, errorIndication))
-            if 'oid' in errorIndication:
-                # Request REPORT generation
-                statusInformation['oid'] = errorIndication['oid']
-                statusInformation['val'] = errorIndication['val']
-
-        # PDU-level SMI errors
-        except pysnmp.smi.error.NoAccessError:
-            errorStatus, errorIndex = 'noAccess', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.WrongTypeError:
-            errorStatus, errorIndex = 'wrongType', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.WrongLengthError:
-            errorStatus, errorIndex = 'wrongLength', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.WrongEncodingError:
-            errorStatus, errorIndex = 'wrongEncoding', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.WrongValueError:
-            errorStatus, errorIndex = 'wrongValue', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.NoCreationError:
-            errorStatus, errorIndex = 'noCreation', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.InconsistentValueError:
-            errorStatus, errorIndex = 'inconsistentValue', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.ResourceUnavailableError:
-            errorStatus, errorIndex = 'resourceUnavailable', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.CommitFailedError:
-            errorStatus, errorIndex = 'commitFailed', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.UndoFailedError:
-            errorStatus, errorIndex = 'undoFailed', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.AuthorizationError:
-            errorStatus, errorIndex = 'authorizationError', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.NotWritableError:
-            errorStatus, errorIndex = 'notWritable', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.InconsistentNameError:
-            errorStatus, errorIndex = 'inconsistentName', sys.exc_info()[1]['idx'] + 1
-        except pysnmp.smi.error.SmiError:
-            errorStatus, errorIndex = 'genErr', len(varBinds) and 1 or 0
-        except pysnmp.error.PySnmpError:
-            self.releaseStateInformation(stateReference)
-            return
-        else:  # successful request processor must release state info
-            return
-
-        self.sendVarBinds(snmpEngine, stateReference, errorStatus,
-                          errorIndex, varBinds)
-
-        self.releaseStateInformation(stateReference)
+        self.initiateMgmtOperation(snmpEngine, stateReference, contextName, PDU)
 
     @classmethod
     def verifyAccess(cls, viewType, varBind, **context):
@@ -259,57 +218,146 @@ class CommandResponderBase(object):
                 # This will cause MibTree to skip this OID-value
                 raise pysnmp.smi.error.NoAccessError(name=name, idx=context.get('idx'))
 
+    def _getMgmtFun(self, contextName):
+        return lambda *args, **kwargs: None
 
-class GetCommandResponder(CommandResponderBase):
-    pduTypes = (rfc1905.GetRequestPDU.tagSet,)
+    def _checkSmiErrors(self, varBinds):
+        errorIndication = None
+        errorStatus = errorIndex = 0
 
-    # rfc1905: 4.2.1
-    def handleMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
-        # rfc1905: 4.2.1.1
-        mgmtFun = self.snmpContext.getMibInstrum(contextName).readVars
+        exception = None
+
+        for idx, varBind in enumerate(varBinds):
+            name, value = varBind
+            if isinstance(value, tuple):  # expect exception tuple
+                debug.logger & debug.flagApp and debug.logger(
+                    '_checkSmiErrors: exception reported for OID %s exception %s' % (name, value))
+
+                if not exception:
+                    exception = value
+
+                # reset exception object
+                varBinds[idx] = name, v2c.null
+
+        try:
+            # TODO: perhaps chain exceptions
+            if exception:
+                debug.logger & debug.flagApp and debug.logger(
+                    '_checkSmiErrors: re-raising exception %s' % (exception,))
+                raise exception[1].with_traceback(exception[2])
+
+        # SNMPv2 SMI exceptions
+        except pysnmp.smi.error.GenError:
+            errorIndication = sys.exc_info()[1]
+            debug.logger & debug.flagApp and debug.logger(
+                '_checkSmiErrors: errorIndication %s' % (errorIndication,))
+
+        except pysnmp.smi.error.SmiError:
+            exc_type, exc_obj, trb = sys.exc_info()
+
+            errorStatus = self.SMI_ERROR_MAP.get(exc_type, 'genErr')
+
+            try:
+                errorIndex = exc_obj['idx'] + 1
+
+            except IndexError:
+                errorIndex = len(varBinds) and 1 or 0
+
+        return errorIndication, errorStatus, errorIndex
+
+    def completeMgmtOperation(self, varBinds, **context):
+
+        try:
+            (errorIndication,
+             errorStatus, errorIndex) = self._checkSmiErrors(varBinds)
+
+        except pysnmp.error.PySnmpError:
+            self.releaseStateInformation(context['stateReference'])
+            return
+
+        stateReference = context['stateReference']
+
+        if errorIndication:
+            statusInformation = self.__pendingReqs[stateReference]['statusInformation']
+
+            try:
+                # Request REPORT generation
+                statusInformation['oid'] = errorIndication['oid']
+                statusInformation['val'] = errorIndication['val']
+
+            except KeyError:
+                pass
+
+        self.sendVarBinds(context['snmpEngine'], stateReference,
+                          errorStatus, errorIndex, varBinds)
+
+        self.releaseStateInformation(stateReference)
+
+    def initiateMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
         varBinds = v2c.apiPDU.getVarBinds(PDU)
 
-        context = dict(snmpEngine=snmpEngine, acFun=self.verifyAccess, cbCtx=self.cbCtx)
+        mgmtFun = self._getMgmtFun(contextName)
 
-        rspVarBinds = mgmtFun(*varBinds, **context)
+        context = dict(snmpEngine=snmpEngine,
+                       stateReference=stateReference,
+                       acFun=self.verifyAccess,
+                       cbFun=self.completeMgmtOperation,
+                       cbCtx=self.cbCtx)
 
-        self.sendVarBinds(snmpEngine, stateReference, 0, 0, rspVarBinds)
-        self.releaseStateInformation(stateReference)
+        mgmtFun(*varBinds, **context)
+
+
+class GetCommandResponder(CommandResponderBase):
+    SUPPORTED_PDU_TYPES = (rfc1905.GetRequestPDU.tagSet,)
+
+    # rfc1905: 4.2.1
+    def _getMgmtFun(self, contextName):
+        return self.snmpContext.getMibInstrum(contextName).readVars
 
 
 class NextCommandResponder(CommandResponderBase):
-    pduTypes = (rfc1905.GetNextRequestPDU.tagSet,)
+    SUPPORTED_PDU_TYPES = (rfc1905.GetNextRequestPDU.tagSet,)
 
     # rfc1905: 4.2.2
-    def handleMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
-        # rfc1905: 4.2.2.1
-        mgmtFun = self.snmpContext.getMibInstrum(contextName).readNextVars
-
-        varBinds = v2c.apiPDU.getVarBinds(PDU)
-
-        context = dict(snmpEngine=snmpEngine, acFun=self.verifyAccess, cbCtx=self.cbCtx)
-
-        while True:
-            rspVarBinds = mgmtFun(*varBinds, **context)
-
-            try:
-                self.sendVarBinds(snmpEngine, stateReference, 0, 0, rspVarBinds)
-
-            except error.StatusInformation:
-                idx = sys.exc_info()[1]['idx']
-                varBinds[idx] = (rspVarBinds[idx][0], varBinds[idx][1])
-            else:
-                break
-
-        self.releaseStateInformation(stateReference)
+    def _getMgmtFun(self, contextName):
+        return self.snmpContext.getMibInstrum(contextName).readNextVars
 
 
 class BulkCommandResponder(CommandResponderBase):
-    pduTypes = (rfc1905.GetBulkRequestPDU.tagSet,)
+    SUPPORTED_PDU_TYPES = (rfc1905.GetBulkRequestPDU.tagSet,)
     maxVarBinds = 64
 
+    def _getMgmtFun(self, contextName):
+        return self.snmpContext.getMibInstrum(contextName).readNextVars
+
+    def _completeNonRepeaters(self, varBinds, **context):
+        context['rspVarBinds'][:] = varBinds
+
+        if context['counters']['M'] and context['counters']['R']:
+            context['cbFun'] = self.completeMgmtOperation
+
+            mgmtFun = self._getMgmtFun(context['contextName'])
+
+            mgmtFun(*context['reqVarBinds'], **context)
+
+        else:
+            CommandResponderBase.completeMgmtOperation(self, context['rspVarBinds'], **context)
+
+    def completeMgmtOperation(self, varBinds, **context):
+        context['rspVarBinds'].extend(varBinds)
+        context['counters']['M'] -= 1
+
+        if context['counters']['M'] and context['counters']['R']:
+            mgmtFun = self._getMgmtFun(context['contextName'])
+
+            context['cbFun'] = self.completeMgmtOperation
+            mgmtFun(*varBinds[-context['counters']['R']:], **context)
+
+        else:
+            CommandResponderBase.completeMgmtOperation(self, context['rspVarBinds'], **context)
+
     # rfc1905: 4.2.3
-    def handleMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
+    def initiateMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
         nonRepeaters = v2c.apiBulkPDU.getNonRepeaters(PDU)
         if nonRepeaters < 0:
             nonRepeaters = 0
@@ -318,68 +366,42 @@ class BulkCommandResponder(CommandResponderBase):
         if maxRepetitions < 0:
             maxRepetitions = 0
 
-        reqVarBinds = v2c.apiPDU.getVarBinds(PDU)
+        varBinds = v2c.apiPDU.getVarBinds(PDU)
 
-        N = min(int(nonRepeaters), len(reqVarBinds))
+        N = min(int(nonRepeaters), len(varBinds))
         M = int(maxRepetitions)
-        R = max(len(reqVarBinds) - N, 0)
+        R = max(len(varBinds) - N, 0)
 
         if R:
             M = min(M, self.maxVarBinds // R)
 
-        debug.logger & debug.flagApp and debug.logger('handleMgmtOperation: N %d, M %d, R %d' % (N, M, R))
+        debug.logger & debug.flagApp and debug.logger(
+            'initiateMgmtOperation: N %d, M %d, R %d' % (N, M, R))
 
-        mgmtFun = self.snmpContext.getMibInstrum(contextName).readNextVars
+        mgmtFun = self._getMgmtFun(contextName)
 
-        context = dict(snmpEngine=snmpEngine, acFun=self.verifyAccess, cbCtx=self.cbCtx)
+        context = dict(snmpEngine=snmpEngine,
+                       stateReference=stateReference,
+                       contextName=contextName,
+                       acFun=self.verifyAccess,
+                       cbFun=self._completeNonRepeaters,
+                       cbCtx=self.cbCtx,
+                       reqVarBinds=varBinds[N:],
+                       counters={'M': M, 'R': R},
+                       rspVarBinds=[])
 
-        if N:
-            # TODO(etingof): manage all PDU var-binds in a single call
-            rspVarBinds = mgmtFun(*reqVarBinds[:N], **context)
-
-        else:
-            rspVarBinds = []
-
-        varBinds = reqVarBinds[-R:]
-
-        while M and R:
-            rspVarBinds.extend(mgmtFun(*varBinds, **context))
-            varBinds = rspVarBinds[-R:]
-            M -= 1
-
-        if len(rspVarBinds):
-            self.sendVarBinds(snmpEngine, stateReference, 0, 0, rspVarBinds)
-            self.releaseStateInformation(stateReference)
-        else:
-            raise pysnmp.smi.error.SmiError()
+        mgmtFun(*varBinds[:N], **context)
 
 
 class SetCommandResponder(CommandResponderBase):
-    pduTypes = (rfc1905.SetRequestPDU.tagSet,)
+    SUPPORTED_PDU_TYPES = (rfc1905.SetRequestPDU.tagSet,)
 
-    # rfc1905: 4.2.5
-    def handleMgmtOperation(self, snmpEngine, stateReference, contextName, PDU):
-        mgmtFun = self.snmpContext.getMibInstrum(contextName).writeVars
+    SMI_ERROR_MAP = CommandResponderBase.SMI_ERROR_MAP.copy()
 
-        varBinds = v2c.apiPDU.getVarBinds(PDU)
+    # turn missing OIDs into access denial
+    SMI_ERROR_MAP[pysnmp.smi.error.NoSuchObjectError] = 'notWritable'
+    SMI_ERROR_MAP[pysnmp.smi.error.NoSuchInstanceError] = 'notWritable'
 
-        instrumError = None
-
-        context = dict(snmpEngine=snmpEngine, acFun=self.verifyAccess, cbCtx=self.cbCtx)
-
-        # rfc1905: 4.2.5.1-13
-        try:
-            rspVarBinds = mgmtFun(*varBinds, **context)
-
-        except (pysnmp.smi.error.NoSuchObjectError,
-                pysnmp.smi.error.NoSuchInstanceError):
-            instrumError = pysnmp.smi.error.NotWritableError()
-            instrumError.update(sys.exc_info()[1])
-
-        else:
-            self.sendVarBinds(snmpEngine, stateReference, 0, 0, rspVarBinds)
-
-        self.releaseStateInformation(stateReference)
-
-        if instrumError:
-            raise instrumError
+    # rfc1905: 4.2.5.1-13
+    def _getMgmtFun(self, contextName):
+        return self.snmpContext.getMibInstrum(contextName).writeVars

pysnmp/entity/rfc3413/ntfrcv.py

@@ -14,12 +14,12 @@ from pysnmp import debug
 
 # 3.4
 class NotificationReceiver(object):
-    pduTypes = (v1.TrapPDU.tagSet, v2c.SNMPv2TrapPDU.tagSet,
-                v2c.InformRequestPDU.tagSet)
+    SUPPORTED_PDU_TYPES = (v1.TrapPDU.tagSet, v2c.SNMPv2TrapPDU.tagSet,
+                           v2c.InformRequestPDU.tagSet)
 
     def __init__(self, snmpEngine, cbFun, cbCtx=None):
         snmpEngine.msgAndPduDsp.registerContextEngineId(
-            null, self.pduTypes, self.processPdu  # '' is a wildcard
+            null, self.SUPPORTED_PDU_TYPES, self.processPdu  # '' is a wildcard
         )
 
         self.__snmpTrapCommunity = ''
@@ -33,7 +33,7 @@ class NotificationReceiver(object):
 
     def close(self, snmpEngine):
         snmpEngine.msgAndPduDsp.unregisterContextEngineId(
-            null, self.pduTypes
+            null, self.SUPPORTED_PDU_TYPES
         )
         self.__cbFun = self.__cbCtx = None
 

pysnmp/hlapi/v3arch/asyncio/cmdgen.py

@@ -145,7 +145,8 @@ def getCmd(snmpEngine, authData, transportTarget, contextData,
                 (errorIndication, errorStatus, errorIndex, varBindsUnmade)
             )
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     future = asyncio.Future()
 
@@ -250,7 +251,8 @@ def setCmd(snmpEngine, authData, transportTarget, contextData,
                 (errorIndication, errorStatus, errorIndex, varBindsUnmade)
             )
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     future = asyncio.Future()
 
@@ -361,7 +363,8 @@ def nextCmd(snmpEngine, authData, transportTarget, contextData,
                 (errorIndication, errorStatus, errorIndex, varBindsUnmade)
             )
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     future = asyncio.Future()
 
@@ -501,7 +504,8 @@ def bulkCmd(snmpEngine, authData, transportTarget, contextData,
                 (errorIndication, errorStatus, errorIndex, varBindsUnmade)
             )
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     future = asyncio.Future()
 

pysnmp/hlapi/v3arch/asyncio/ntforg.py

@@ -152,8 +152,8 @@ def sendNotification(snmpEngine, authData, transportTarget, contextData,
             )
 
     notifyName = lcd.configure(
-        snmpEngine, authData, transportTarget, notifyType
-    )
+        snmpEngine, authData, transportTarget, notifyType,
+        contextData.contextName)
 
     future = asyncio.Future()
 

pysnmp/hlapi/v3arch/asyncore/cmdgen.py

@@ -121,7 +121,8 @@ def getCmd(snmpEngine, authData, transportTarget, contextData,
                              snmpEngine.cache, varBinds, lookupMib
                          ), cbCtx)
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     return cmdgen.GetCommandGenerator().sendVarBinds(
         snmpEngine, addrName, contextData.contextEngineId,
@@ -232,7 +233,8 @@ def setCmd(snmpEngine, authData, transportTarget, contextData,
                          snmpEngine.cache, varBinds, lookupMib
                      ), cbCtx)
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     return cmdgen.SetCommandGenerator().sendVarBinds(
         snmpEngine, addrName, contextData.contextEngineId,
@@ -343,7 +345,9 @@ def nextCmd(snmpEngine, authData, transportTarget, contextData,
                       varBindTable],
                      cbCtx)
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
+
     return cmdgen.NextCommandGenerator().sendVarBinds(
         snmpEngine, addrName,
         contextData.contextEngineId, contextData.contextName,
@@ -483,7 +487,8 @@ def bulkCmd(snmpEngine, authData, transportTarget, contextData,
                      [vbProcessor.unmakeVarBinds(snmpEngine.cache, varBindTableRow, lookupMib) for varBindTableRow in
                       varBindTable], cbCtx)
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     return cmdgen.BulkCommandGenerator().sendVarBinds(
         snmpEngine, addrName, contextData.contextEngineId,

pysnmp/hlapi/v3arch/asyncore/ntforg.py

@@ -162,7 +162,7 @@ def sendNotification(snmpEngine, authData, transportTarget, contextData,
         )
 
     notifyName = lcd.configure(snmpEngine, authData, transportTarget,
-                               notifyType)
+                               notifyType, contextData.contextName)
 
     return ntforg.NotificationOriginator().sendVarBinds(
         snmpEngine, notifyName,

pysnmp/hlapi/v3arch/lcd.py

@@ -8,6 +8,8 @@ from pysnmp.entity import config
 from pysnmp import nextid, error
 from pysnmp.hlapi.v3arch.auth import *
 
+from pyasn1.compat.octets import null
+
 __all__ = ['CommandGeneratorLcdConfigurator',
            'NotificationOriginatorLcdConfigurator']
 
@@ -24,17 +26,17 @@ class AbstractLcdConfigurator(object):
             snmpEngine.setUserContext(**{cacheId: cache})
         return cache
 
-    def configure(self, snmpEngine, authData, transportTarget, *options):
+    def configure(self, snmpEngine, *args, **kwargs):
         pass
 
-    def unconfigure(self, snmpEngine, authData=None):
+    def unconfigure(self, snmpEngine, *args, **kwargs):
         pass
 
 
 class CommandGeneratorLcdConfigurator(AbstractLcdConfigurator):
     cacheKeys = ['auth', 'parm', 'tran', 'addr']
 
-    def configure(self, snmpEngine, authData, transportTarget, *options):
+    def configure(self, snmpEngine, authData, transportTarget, contextName, **options):
         cache = self._getCache(snmpEngine)
         if isinstance(authData, CommunityData):
             if authData.communityIndex not in cache['auth']:
@@ -117,7 +119,7 @@ class CommandGeneratorLcdConfigurator(AbstractLcdConfigurator):
 
         return addrName, paramsName
 
-    def unconfigure(self, snmpEngine, authData=None):
+    def unconfigure(self, snmpEngine, authData=None, contextName=null, **options):
         cache = self._getCache(snmpEngine)
         if authData:
             if isinstance(authData, CommunityData):
@@ -198,9 +200,9 @@ class NotificationOriginatorLcdConfigurator(AbstractLcdConfigurator):
     cacheKeys = ['auth', 'name']
     _cmdGenLcdCfg = CommandGeneratorLcdConfigurator()
 
-    def configure(self, snmpEngine, authData, transportTarget, *options):
+    def configure(self, snmpEngine, authData, transportTarget, notifyType,
+                  contextName, **options):
         cache = self._getCache(snmpEngine)
-        notifyType = options and options[0] or 'trap'
         notifyName = None
 
         # Create matching transport tags if not given by user. Not good!
@@ -211,7 +213,8 @@ class NotificationOriginatorLcdConfigurator(AbstractLcdConfigurator):
         if isinstance(authData, CommunityData) and not authData.tag:
             authData.tag = transportTarget.tagList.split()[0]
 
-        addrName, paramsName = self._cmdGenLcdCfg.configure(snmpEngine, authData, transportTarget)
+        addrName, paramsName = self._cmdGenLcdCfg.configure(
+            snmpEngine, authData, transportTarget, contextName, **options)
         tagList = transportTarget.tagList.split()
         if not tagList:
             tagList = ['']
@@ -230,7 +233,7 @@ class NotificationOriginatorLcdConfigurator(AbstractLcdConfigurator):
                     notifyType
                 )
                 cache['name'][notifyNameKey] = notifyName, paramsName, 1
-        authDataKey = authData.securityName, authData.securityModel
+        authDataKey = authData.securityName, authData.securityModel, authData.securityLevel, contextName
         if authDataKey in cache['auth']:
             authDataX, subTree, useCount = cache['auth'][authDataKey]
             cache['auth'][authDataKey] = authDataX, subTree, useCount + 1
@@ -240,23 +243,24 @@ class NotificationOriginatorLcdConfigurator(AbstractLcdConfigurator):
                                authData.securityModel,
                                authData.securityName,
                                authData.securityLevel,
-                               (), (), subTree)
+                               (), (), subTree, contextName=contextName)
             cache['auth'][authDataKey] = authData, subTree, 1
 
         return notifyName
 
-    def unconfigure(self, snmpEngine, authData=None):
+    def unconfigure(self, snmpEngine, authData=None, contextName=null, **options):
         cache = self._getCache(snmpEngine)
         if authData:
-            authDataKey = authData.securityName, authData.securityModel
+            authDataKey = authData.securityName, authData.securityModel, authData.securityLevel, contextName
             if authDataKey in cache['auth']:
                 authDataKeys = (authDataKey,)
             else:
                 raise error.PySnmpError('Unknown authData %s' % (authData,))
         else:
-            authDataKeys = tuple(cache['auth'].keys())
+            authDataKeys = tuple(cache['auth'])
 
-        addrNames, paramsNames = self._cmdGenLcdCfg.unconfigure(snmpEngine, authData)
+        addrNames, paramsNames = self._cmdGenLcdCfg.unconfigure(
+            snmpEngine, authData, contextName, **options)
 
         notifyAndParamsNames = [(cache['name'][x], x) for x in cache['name'].keys() if x[0] in paramsNames]
 

pysnmp/hlapi/v3arch/twisted/cmdgen.py

@@ -128,7 +128,8 @@ def getCmd(snmpEngine, authData, transportTarget, contextData,
             else:
                 deferred.callback((errorStatus, errorIndex, varBindsUnmade))
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     deferred = Deferred()
 
@@ -244,7 +245,8 @@ def setCmd(snmpEngine, authData, transportTarget, contextData,
             else:
                 deferred.callback((errorStatus, errorIndex, varBindsUnmade))
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     deferred = Deferred()
 
@@ -374,7 +376,8 @@ def nextCmd(snmpEngine, authData, transportTarget, contextData,
             else:
                 deferred.callback((errorStatus, errorIndex, varBindsUnmade))
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     deferred = Deferred()
 
@@ -532,7 +535,8 @@ def bulkCmd(snmpEngine, authData, transportTarget, contextData,
             else:
                 deferred.callback((errorStatus, errorIndex, varBindsUnmade))
 
-    addrName, paramsName = lcd.configure(snmpEngine, authData, transportTarget)
+    addrName, paramsName = lcd.configure(
+        snmpEngine, authData, transportTarget, contextData.contextName)
 
     deferred = Deferred()
 

pysnmp/hlapi/v3arch/twisted/ntforg.py

@@ -166,9 +166,8 @@ def sendNotification(snmpEngine, authData, transportTarget, contextData,
             else:
                 deferred.callback((errorStatus, errorIndex, varBindsUnmade))
 
-    notifyName = lcd.configure(
-        snmpEngine, authData, transportTarget, notifyType
-    )
+    notifyName = lcd.configure(snmpEngine, authData, transportTarget,
+                               notifyType, contextData.contextName)
 
     def __trapFun(deferred):
         deferred.callback((0, 0, []))

pysnmp/proto/rfc1902.py

@@ -10,7 +10,32 @@ from pysnmp.proto import rfc1155, error
 
 __all__ = ['Opaque', 'TimeTicks', 'Bits', 'Integer', 'OctetString',
            'IpAddress', 'Counter64', 'Unsigned32', 'Gauge32', 'Integer32',
-           'ObjectIdentifier', 'Counter32']
+           'ObjectIdentifier', 'Counter32', 'Null']
+
+
+class Null(univ.Null):
+    """Creates an instance of SNMP Null class.
+
+    :py:class:`~pysnmp.proto.rfc1902.Null` type represents the absence
+    of value.
+
+    Parameters
+    ----------
+    initializer: str
+        Python string object. Must be an empty string.
+
+    Raises
+    ------
+        PyAsn1Error :
+            On constraint violation or bad initializer.
+
+    Examples
+    --------
+        >>> from pysnmp.proto.rfc1902 import *
+        >>> Null('')
+        Null('')
+        >>>
+    """
 
 
 class Integer32(univ.Integer):

pysnmp/smi/builder.py

@@ -263,7 +263,7 @@ class MibBuilder(object):
         self.mibSymbols = {}
         self.__mibSources = []
         self.__modSeen = {}
-        self.__modPathsSeen = {}
+        self.__modPathsSeen = set()
         self.__mibCompiler = None
         self.setMibSources(*sources)
 
@@ -306,19 +306,19 @@ class MibBuilder(object):
                 debug.logger & debug.flagBld and debug.logger('loadModule: seen %s' % modPath)
                 break
             else:
-                self.__modPathsSeen[modPath] = 1
+                self.__modPathsSeen.add(modPath)
 
             debug.logger & debug.flagBld and debug.logger('loadModule: evaluating %s' % modPath)
 
             g = {'mibBuilder': self, 'userCtx': userCtx}
 
             try:
-                exec (modData, g)
+                exec(compile(modData, modPath, 'exec'), g)
 
             except Exception:
                 del self.__modPathsSeen[modPath]
                 raise error.MibLoadError(
-                    'MIB module \"%s\" load error: %s' % (modPath, traceback.format_exception(*sys.exc_info()))
+                    'MIB module \'%s\' load error: %s' % (modPath, traceback.format_exception(*sys.exc_info()))
                 )
 
             self.__modSeen[modName] = modPath

pysnmp/smi/instrum.py

@@ -6,6 +6,8 @@
 #
 import sys
 import traceback
+import functools
+from pysnmp import nextid
 from pysnmp.smi import error
 from pysnmp import debug
 
@@ -24,39 +26,59 @@ class AbstractMibInstrumController(object):
 
 
 class MibInstrumController(AbstractMibInstrumController):
+    STATUS_OK = 'ok'
+    STATUS_ERROR = 'err'
+    
+    STATE_START = 'start'
+    STATE_STOP = 'stop'
+    STATE_ANY = '*'
+    # These states are actually methods of the MIB objects
+    STATE_READ_TEST = 'readTest'
+    STATE_READ_GET = 'readGet'
+    STATE_READ_TEST_NEXT = 'readTestNext'
+    STATE_READ_GET_NEXT = 'readGetNext'
+    STATE_WRITE_TEST = 'writeTest'
+    STATE_WRITE_COMMIT = 'writeCommit'
+    STATE_WRITE_CLEANUP = 'writeCleanup'
+    STATE_WRITE_UNDO = 'writeUndo'
+
     fsmReadVar = {
         # ( state, status ) -> newState
-        ('start', 'ok'): 'readTest',
-        ('readTest', 'ok'): 'readGet',
-        ('readGet', 'ok'): 'stop',
-        ('*', 'err'): 'stop'
+        (STATE_START, STATUS_OK): STATE_READ_TEST,
+        (STATE_READ_TEST, STATUS_OK): STATE_READ_GET,
+        (STATE_READ_GET, STATUS_OK): STATE_STOP,
+        (STATE_ANY, STATUS_ERROR): STATE_STOP
     }
     fsmReadNextVar = {
         # ( state, status ) -> newState
-        ('start', 'ok'): 'readTestNext',
-        ('readTestNext', 'ok'): 'readGetNext',
-        ('readGetNext', 'ok'): 'stop',
-        ('*', 'err'): 'stop'
+        (STATE_START, STATUS_OK): STATE_READ_TEST_NEXT,
+        (STATE_READ_TEST_NEXT, STATUS_OK): STATE_READ_GET_NEXT,
+        (STATE_READ_GET_NEXT, STATUS_OK): STATE_STOP,
+        (STATE_ANY, STATUS_ERROR): STATE_STOP
     }
     fsmWriteVar = {
         # ( state, status ) -> newState
-        ('start', 'ok'): 'writeTest',
-        ('writeTest', 'ok'): 'writeCommit',
-        ('writeCommit', 'ok'): 'writeCleanup',
-        ('writeCleanup', 'ok'): 'readTest',
+        (STATE_START, STATUS_OK): STATE_WRITE_TEST,
+        (STATE_WRITE_TEST, STATUS_OK): STATE_WRITE_COMMIT,
+        (STATE_WRITE_COMMIT, STATUS_OK): STATE_WRITE_CLEANUP,
+        (STATE_WRITE_CLEANUP, STATUS_OK): STATE_READ_TEST,
         # Do read after successful write
-        ('readTest', 'ok'): 'readGet',
-        ('readGet', 'ok'): 'stop',
+        (STATE_READ_TEST, STATUS_OK): STATE_READ_GET,
+        (STATE_READ_GET, STATUS_OK): STATE_STOP,
         # Error handling
-        ('writeTest', 'err'): 'writeCleanup',
-        ('writeCommit', 'err'): 'writeUndo',
-        ('writeUndo', 'ok'): 'readTest',
+        (STATE_WRITE_TEST, STATUS_ERROR): STATE_WRITE_CLEANUP,
+        (STATE_WRITE_COMMIT, STATUS_ERROR): STATE_WRITE_UNDO,
+        (STATE_WRITE_UNDO, STATUS_OK): STATE_READ_TEST,
         # Ignore read errors (removed columns)
-        ('readTest', 'err'): 'stop',
-        ('readGet', 'err'): 'stop',
-        ('*', 'err'): 'stop'
+        (STATE_READ_TEST, STATUS_ERROR): STATE_STOP,
+        (STATE_READ_GET, STATUS_ERROR): STATE_STOP,
+        (STATE_ANY, STATUS_ERROR): STATE_STOP
     }
 
+    FSM_CONTEXT = '_fsmContext'
+
+    FSM_SESSION_ID = nextid.Integer(0xffffffff)
+
     def __init__(self, mibBuilder):
         self.mibBuilder = mibBuilder
         self.lastBuildId = -1
@@ -183,82 +205,121 @@ class MibInstrumController(AbstractMibInstrumController):
 
     # MIB instrumentation
 
-    def flipFlopFsm(self, fsmTable, *varBinds, **context):
-        self.__indexMib()
+    def _flipFlopFsmCb(self, varBind, **context):
+        fsmContext = context[self.FSM_CONTEXT]
 
-        debug.logger & debug.flagIns and debug.logger('flipFlopFsm: input var-binds %r' % (varBinds,))
+        varBinds = fsmContext['varBinds']
+
+        idx = context.pop('idx')
+
+        if idx >= 0:
+            fsmContext['count'] += 1
+
+            varBinds[idx] = varBind
+
+            debug.logger & debug.flagIns and debug.logger(
+                '_flipFlopFsmCb: var-bind %d, processed %d, expected %d' % (idx, fsmContext['count'], len(varBinds)))
+
+            if fsmContext['count'] < len(varBinds):
+                return
+
+        debug.logger & debug.flagIns and debug.logger(
+            '_flipFlopFsmCb: finished, output %r' % (varBinds,))
+
+        fsmCallable = fsmContext['fsmCallable']
+
+        fsmCallable(**context)
+
+    def flipFlopFsm(self, fsmTable, *varBinds, **context):
+        try:
+            fsmContext = context[self.FSM_CONTEXT]
+
+        except KeyError:
+            self.__indexMib()
+
+            fsmContext = context[self.FSM_CONTEXT] = dict(
+                sessionId=self.FSM_SESSION_ID(),
+                varBinds=list(varBinds[:]),
+                fsmCallable=functools.partial(self.flipFlopFsm, fsmTable, *varBinds),
+                state=self.STATE_START, status=self.STATUS_OK
+            )
+
+            debug.logger & debug.flagIns and debug.logger('flipFlopFsm: input var-binds %r' % (varBinds,))
 
         mibTree, = self.mibBuilder.importSymbols('SNMPv2-SMI', 'iso')
 
-        outputVarBinds = []
-        state, status = 'start', 'ok'
-        origExc = origTraceback = None
-        while True:
-            k = state, status
-            if k in fsmTable:
-                fsmState = fsmTable[k]
+        state = fsmContext['state']
+        status = fsmContext['status']
+
+        debug.logger & debug.flagIns and debug.logger(
+            'flipFlopFsm: current state %s, status %s' % (state, status))
+
+        try:
+            newState = fsmTable[(state, status)]
+
+        except KeyError:
+            try:
+                newState = fsmTable[(self.STATE_ANY, status)]
+
+            except KeyError:
+                raise error.SmiError('Unresolved FSM state %s, %s' % (state, status))
+
+        debug.logger & debug.flagIns and debug.logger(
+            'flipFlopFsm: state %s status %s -> new state %s' % (state, status, newState))
+
+        state = newState
+
+        if state == self.STATE_STOP:
+            context.pop(self.FSM_CONTEXT, None)
+
+            cbFun = context.get('cbFun')
+            if cbFun:
+                varBinds = fsmContext['varBinds']
+                cbFun(varBinds, **context)
+
+            return
+
+        fsmContext.update(state=state, count=0)
+
+        # the case of no var-binds
+        if not varBinds:
+            return self._flipFlopFsmCb(None, idx=-1, **context)
+
+        mgmtFun = getattr(mibTree, state, None)
+        if not mgmtFun:
+            raise error.SmiError(
+                'Unsupported state handler %s at %s' % (state, self)
+            )
+
+        for idx, varBind in enumerate(varBinds):
+            try:
+                # TODO: managed objects to run asynchronously
+                #mgmtFun(varBind, idx=idx, **context)
+                self._flipFlopFsmCb(mgmtFun(varBind, idx=idx, **context), idx=idx, **context)
+
+            except error.SmiError:
+                exc = sys.exc_info()
+                debug.logger & debug.flagIns and debug.logger(
+                    'flipFlopFsm: fun %s exception %s for %r with traceback: %s' % (
+                        mgmtFun, exc[0], varBind, traceback.format_exception(*exc)))
+
+                varBind = varBind[0], exc
+
+                fsmContext['status'] = self.STATUS_ERROR
+
+                self._flipFlopFsmCb(varBind, idx=idx, **context)
+
+                return
+
             else:
-                k = '*', status
-                if k in fsmTable:
-                    fsmState = fsmTable[k]
-                else:
-                    raise error.SmiError(
-                        'Unresolved FSM state %s, %s' % (state, status)
-                    )
-            debug.logger & debug.flagIns and debug.logger(
-                'flipFlopFsm: state %s status %s -> fsmState %s' % (state, status, fsmState))
-            state = fsmState
-            status = 'ok'
-            if state == 'stop':
-                break
-
-            for idx, (name, val) in enumerate(varBinds):
-                mgmtFun = getattr(mibTree, state, None)
-                if not mgmtFun:
-                    raise error.SmiError(
-                        'Unsupported state handler %s at %s' % (state, self)
-                    )
-
-                context['idx'] = idx
-
-                try:
-                    # Convert to tuple to avoid ObjectName instantiation
-                    # on subscription
-                    rval = mgmtFun((tuple(name), val), **context)
-
-                except error.SmiError:
-                    exc_t, exc_v, exc_tb = sys.exc_info()
-                    debug.logger & debug.flagIns and debug.logger(
-                        'flipFlopFsm: fun %s exception %s for %s=%r with traceback: %s' % (
-                            mgmtFun, exc_t, name, val, traceback.format_exception(exc_t, exc_v, exc_tb)))
-                    if origExc is None:  # Take the first exception
-                        origExc, origTraceback = exc_v, exc_tb
-                    status = 'err'
-                    break
-                else:
-                    debug.logger & debug.flagIns and debug.logger(
-                        'flipFlopFsm: fun %s suceeded for %s=%r' % (mgmtFun, name, val))
-                    if rval is not None:
-                        outputVarBinds.append((rval[0], rval[1]))
-
-        if origExc:
-            if sys.version_info[0] <= 2:
-                raise origExc
-            else:
-                try:
-                    raise origExc.with_traceback(origTraceback)
-                finally:
-                    # Break cycle between locals and traceback object
-                    # (seems to be irrelevant on Py3 but just in case)
-                    del origTraceback
-
-        return outputVarBinds
+                debug.logger & debug.flagIns and debug.logger(
+                    'flipFlopFsm: func %s initiated for %r' % (mgmtFun, varBind))
 
     def readVars(self, *varBinds, **context):
-        return self.flipFlopFsm(self.fsmReadVar, *varBinds, **context)
+        self.flipFlopFsm(self.fsmReadVar, *varBinds, **context)
 
     def readNextVars(self, *varBinds, **context):
-        return self.flipFlopFsm(self.fsmReadNextVar, *varBinds, **context)
+        self.flipFlopFsm(self.fsmReadNextVar, *varBinds, **context)
 
     def writeVars(self, *varBinds, **context):
-        return self.flipFlopFsm(self.fsmWriteVar, *varBinds, **context)
+        self.flipFlopFsm(self.fsmWriteVar, *varBinds, **context)